Mechanisms of Raf-1 Kinase Inhibitor Protein Dysregulation in Triple-Negative Breast Cancers and Identification of Possible Novel Therapeutic Approaches for These Tumors

Triple-negative breast cancers (TNBCs) are a heterogenous group of breast cancers characterized by poor prognosis because they are not amenable to targeted therapies. We have taken into account that altered expression of Raf-1 kinase inhibitor protein (RKIP), a tumor and metastasis suppressor and a promoter of drug-induced apoptosis, is frequent in TNBCs and may be involved in their aggressive biology. Interestingly, the analysis of the possible mechanisms of RKIP downregulation in TNBCs permits the identification and recapitulation of different possible approaches, including epigenetic modulation, e.g., by DNA demethylating agents or histone deacetylase inhibition, and NF-κB inhibition. Th…

Expression of IAPs and alternative splice variants in hepatocellular carcinoma tissues and cells.

IAPs (inhibitors of apoptosis proteins) might have a major role in the apoptotic resistance that marks many cancers. The studies on IAPs in human HCC have focused on survivin or XIAP, indicating that their new or increased expression in this tumor is associated with a more unfavorable prognosis. The present results corroborate these findings, emphasizing the role that the coordinated expression of different IAPs and alternative splice variants might play in the adverse biology of hepatocellular carcinoma.

Expression of WISPs and of their novel alternative variants in human hepatocellular carcinoma cells

WISPs (Wnt-induced secreted proteins) are members of the CCN (CTGF/Cyr61/Nov) family involved in fibrotic disorders and tumorigenesis. They have a typical structure composed of four conserved cysteine-rich modular domains, but variants of CCN members lacking one or more modules, generated by alternative splicing or gene mutations, have been described in various pathological conditions. WISP genes were first described as downstream targets of the Wnt signaling pathway, which is frequently altered in human hepatocellular carcinoma (HCC). In the present study, WISP mRNA expression was analyzed by RT-PCR in four human HCC cell lines (HepG2, HuH-6, HuH-7, HA22T/VGH). Our results show for the fir…

Expression of the IAPs in multidrug resistant tumor cells

We have investigated the expression of the IAPs (inhibitory of apoptosis proteins) in the human HL-60 leukemia and in its multidrug resistant, P-glycoprotein (P-gp) over-expressing variant, HL-60R. HL-60R exhibits resistance to apoptosis induced from P-gp substrate drugs and also from other triggers (cisplatin, TNF-alpha, Fas ligation, TRAIL, IFN-gamma and serum starvation) not related to the multidrug transporter. Except for c-IAP-1 mRNA, HL-60R significantly over-expressed both the mRNAs and the proteins of all the IAPs studied, i.e. c-IAP-1, c-IAP-2, XIAP, NAIP and survivin. Determination of the DNA-binding capacity of NF-kappaB (p50 or p65 subunits) indicated that, while HL-60 cells sho…

Resistance to diverse apoptotic triggers in multidrug resistant HL60 cells and its possible relationship to the expression of P-glycoprotein, Fas and of the novel anti-apoptosis factors IAP (inhibitory of apoptosis proteins)

We studied the human HL60 leukemia cell line and its multidrug resistant (MDR) variant HL60R. In contrast to the HL60, HL60R showed an inability to undergo apoptosis from doxorubicin (Dox) or other different stimuli, including cisplatin, Fas ligation and serum withdrawal. HL60R cells lost surface Fas expression, but we found no evidence that Fas/FasL mediates the apoptotic effects of Dox in HL60. P-glycoprotein (P-gp) did not seem to play a major role as a specific inhibitor of apoptosis. In fact, the P-gp inhibitor verapamil reversed only partially the resistance to Dox-induced apoptosis of the MDR cells. In addition, it did not modify the rate of apoptosis induced from the other stimuli i…

Induction of apoptosis by the adenosine derivative IB-MECA in parental or multidrug-resistant HL-60 leukemia cells: possible relationship to the effects on inhibitor of apoptosis protein levels.

<i>Background:</i> The effects of the A<sub>3</sub> adenosine receptor (A<sub>3</sub>AR) agonist IB-MECA were examined in HL-60 leukemia and in its multidrug-resistant variant HL-60R cells. <i>Methods:</i> Cytotoxicity was evaluated by MTS assays and apoptosis by flow cytometry analyses of DNA fragmentation and phosphatidylserine exposure. The mRNAs of A<sub>3</sub>AR and inhibitor of apoptosis proteins (IAPs) were determined by RT-PCR. <i>Results:</i> A<sub>3</sub>AR expression was similar in HL-60 and HL-60R cells. At ≧100 µ<i>M</i>, IB-MECA exhibited strong cytotoxic and apoptotic effects in H…

Frequent Alteration of the Yin Yang 1/Raf-1 Kinase Inhibitory Protein Ratio in Hepatocellular Carcinoma

The transcription factor Yin Yang 1 (YY1) can favor several aspects of tumorigenesis. In turn, Raf-1 Kinase Inhibitor Protein (RKIP) inhibits the oncogenic activities of MAPK and NF-κB pathways and promotes drug-induced apoptosis. Mutual influences between YY1 and RKIP may exist, and there are already separate evidences that relevant increases in YY1 and reductions in RKIP occur in hepatocellular carcinoma (HCC). However, the levels of the two factors have never been concomitantly examined in HCC. We evaluated by RT-PCR the mRNA levels of YY1, YY1AP, RKIP, and survivin in 35 clinical HCCs (91% HCV-related), in their adjacent cirrhotic tissues and in 6 healthy livers. Immunohistochemical ana…

Nanocarrier based on halloysite and fluorescent probe for intracellular delivery of peptide nucleic acids

The development of systems able to deliver genetic material into a target site is a challenge for modern medicine. Single-stranded peptide nucleic acids have attracted attention as promising therapeutic molecules for diagnostic and gene therapy. However, their poor cell membrane permeability represents a drawback for biomedical applications. Halloysite nanotubes (HNTs) are emerging materials in drug delivery applications both for their ability to penetrate cell membranes and for enhancing the solubility of drugs in biological media. Herein, we report the first example of the use of a nanocarrier based on halloysite labelled with fluorescent switchable halochromic oxazine molecules, to deliv…

Prostaglandin E2 receptors and COX enxymes in human hepatocellular carcinoma: role in the regulation of cell growth

The aim of this study was to investigate the expression of prostaglandin E 2 receptors (EP 1-4 ), cyclooxygenase-1 (COX-1), and COX-2 in nontumor and tumor human liver tissues, and also to evaluate the antitumor activity of selective EP 1 receptor antagonist used alone or in combination with COX-1 and COX-2 selective inhibitors. Semiquantitative PCR analyses revealed that EP 1-4 , COX-1, and COX-2 mRNA expression was detected in nearly all the tissue samples assayed, although with a high variability between nontumor and tumor tissues. In vitro EP 1 receptor antagonist inhibited anchorage-independent cell growth and reduced the viability of hepatocellular carcinoma (HCC) cells in a dose-depe…

Exploring the cellular uptake of hectorite clay mineral and its drug carrier capabilities.

In the last years, the use of clay minerals for pharmaceutical purposes has increased due to their interesting properties. Hectorite (Ht) is a clay belonging to the smectite group which has attracted attention for applications in biology, tissue engineering and as drug carrier and delivery system. However, the mechanisms involved in Ht cellular uptake and transport into cells, are still unclear. Herein, we used a labeled Ht (Ht/1Cl) to study both the cellular uptake, by confocal laser scanning microscopy, and internalization pathways involved in the cellular uptake, by various endocytosis-inhibiting studies and fluorescence microscopy. These studies highlighted that Ht can penetrate the cel…

Natural Inhibitors of P-glycoprotein in AcuteMyeloid Leukemia

Acute myeloid leukemia (AML) remains an insidious neoplasm due to the percentage of patients who develop resistance to both classic chemotherapy and emerging drugs. Multidrug resistance (MDR) is a complex process determined by multiple mechanisms, and it is often caused by the overexpression of efflux pumps, the most important of which is P-glycoprotein (P-gp). This mini-review aims to examine the advantages of using natural substances as P-gp inhibitors, focusing on four molecules: phytol, curcumin, lupeol, and heptacosane, and their mechanism of action in AML.

Down-regulation of wild-type β-catenin expression by interleukin 6 in human hepatocarcinoma HepG2 and leukemia HL60 cells: a possible role in the growth-inhibitory effects of the cytokine?

Rash and multiorgan dysfunction following lamotrigine: could genetic be involved?

We report the case of a 38-year-old woman treated with lamotrigine who experienced multi-organ dysfunction. The patient received the drug at the dose of 100 mg per day. One week later, the treatment was suspended because of an extensive body rash. Twenty-four hours later, the patient appeared drowsy and stuporous and was hospitalized. On the fifth day, the patient was admitted with a clinical picture of acute multi-organ failure in our Institute, where, she, despite the support of vital functions with vasoactive drugs, continuous hemofiltration and ventilation with oxygen, died. Serum lamotrigine concentration was measured 110 h after its last dose and the drug resulted to be still present …

Targeting multiple myeloma with natural polyphenols

Multiple myeloma (MM) is still an incurable hematologic malignancy. Although new therapeutic strategies have been developed to target different pathways in malignant cells, such as proliferation, differentiation, and apoptosis, better survival rates have also been achieved by the introduction of autologous stem cell transplantation (ASCT). Hematopoietic stem cell transplantation and novel targeted agents, such as proteasome inhibitors, monoclonal antibodies, immunomodulatory drugs, check-point inhibitors and epigenetic modulators, have significantly achieved long remission time and increased survival rates. However, most patients relapse, develop resistance, and eventually die because of re…

Novel insights on [1,2]oxazolo[5,4‐e]isoindoles on multidrug resistant acute myeloid leukemia cell line

A series of [1,2]oxazolo[5,4‐e]isoindole derivatives was evaluated against HL‐60 cell line and its multidrug resistance (MDR) variant, HL‐60R, resistant to doxorubicin and to other P‐gp substrates by overexpressing the efflux pump. They displayed antiproliferative activities, with IC50 values ranging from 0.02 to 5.5μM. In particular, the newly synthesized compound 4k produced synergistic effects in terms of cell growth inhibition and cell death induction either in combination with a Vinca alkaloid, Vinblastine, and a Taxane, Paclitaxel in HL‐60R cells. The study of the mechanism of action indicated that all compounds showed antimitotic activity through inhibition of tubulin polymerization.…

Prodrug based on halloysite delivery systems to improve the antitumor ability of methotrexate in leukemia cell lines

The prodrug approach, as well as the development of specific systems able to deliver a chemotherapeutic agent in the target site, decreasing the side effects often associated with its administration, are still a challenging. In this context, both methotrexate drug molecules (MTX) and biotin ligand moieties, whose receptors are overexpressed on the surface of several cancer cells, were loaded on halloysite nanotubes (HNTs) to develop nanomaterial based on multifunctional and "smart" delivery systems. To highlight the crucial role played by biotin, carrier systems based on HNTs and MTX were also synthetized. In detail, several approaches were envisaged: i) a supramolecular interaction between…

NF-κB Is a Potential Molecular Drug Target in Triple-Negative Breast Cancers.

Breast cancer continues to cause significant burden in global health morbidity and mortality. Triple-negative breast cancers (TNBCs) are highly aggressive with poor prognosis and are characterized by lack of expression of estrogen receptor, progesterone receptor, and human epidermal growth factor receptor (Her-2). TNBCs are often resistant to cytotoxic chemotherapy and pose major difficulty in achieving personalized medicine due to their molecular heterogeneity. There is increasing evidence that the aberrant activation of nuclear factor (NF)-κB signaling is a frequent characteristic of TNBCs. We evaluated the effects of different potential NF-κB inhibitors, such as bisindolylmaleimide I (BI…

Can NF-κB Be Considered a Valid Drug Target in Neoplastic Diseases? Our Point of View

Multidrug resistance (MDR), of the innate and acquired types, is one of major problems in treating tumor diseases with a good chance of success. In this review, we examine the key role of nuclear factor-kappa B (NF-κB) to induce MDR in three tumor models characterized precisely by innate or acquired MDR, in particular triple negative breast cancer (TNBC), hepatocellular carcinoma (HCC), and acute myeloid leukemia (AML). We also present different pharmacological approaches that our group have employed to reduce the expression/activation of this transcriptional factor and thus to restore chemo-sensitivity. Finally, we examine the latest scientific evidence found by other groups, the most sign…

Antitumor effects of the novel NF-κB inhibitor dehydroxymethyl-epoxyquinomicin on human hepatic cancer cells: analysis of synergy with cisplatin and of possible correlation with inhibition of pro-survival genes and IL-6 production

We tested the novel NF-kappaB inhibitor dehydroxymethylepoxyquinomicin (DHMEQ) in the hepatic cancer (HCC) HepG2, HA22T/VGH and HuH-6 cells. The sensitivity to the cell growth inhibitory and apoptotic effects of the agent increased along with the levels of constitutively activated NF-kappaB, which were low in HepG2 and higher in HA22T/VGH and HuH-6. In HA22T/VGH, DHMEQ exhibited synergy with cisplatin. In the same cells, DHMEQ exerted dose-dependent decreases in the nuclear levels of activated NF-kappaB and attenuated NF-kappaB activation by cisplatin. It down-regulated Bcl-XL mRNA in a dose-dependent manner and up-regulated that of Bcl-XS. It also decreased interleukin 6 (IL-6), NAIP and, …

Unusual high dose of tacrolimus in liver transplant patient, a case report.

Case We describe the case of a liver transplant patient who had great difficulty in reaching the desired trough blood levels despite the use of high dose tacrolimus. The patient was homozygous for the CYP3A5*3 allele. However, the respective donor carried the wild-type CYP3A5*1/*1 genotype. Regarding ABCB1 SNPs at exon 21 and 26, the patient showed the 2677GT and 3435CC genotypes. For the corresponding donor we observed the 2677GG and 3435CC wild-type genotypes. One, two and three weeks after transplantation the patient received daily 0.219, 0.287 and 0.273 mg/kg of tacrolimus, respectively. However, the corresponding tacrolimus trough blood levels were of 4.6, 5.6 and 6.1 ng/mL. The tacrol…

Analysis of Possible Mechanisms Accounting for Raf-1 Kinase Inhibitor Protein Downregulation in Hepatocellular Carcinoma

Abstract Raf-1 kinase inhibitor protein (RKIP) is a tumor and metastasis suppressor that promotes drug-induced apoptosis in cancer cells. It is frequently downregulated, both at the mRNA and protein level, in hepatocellular carcinoma (HCC), but the mechanisms leading to this reduction are obscure. We sequenced the whole RKIP gene in three human HCC cell lines (HA22T/VGH, HepG2, and Hep3B), and in five clinical HCC samples, but could not find any gene variant that might account for their low RKIP levels. We also examined whether gene methylation may be responsible for the altered RKIP expression. No methylation of the RKIP gene was found in the tumor samples, while among the cell lines only …

Supramolecular Association of Halochromic Switches and Halloysite Nanotubes in Fluorescent Nanoprobes for Tumor Detection

Fluorescence imaging has become an indispensable tool in the biomedical laboratory to elucidate the fundamental dynamic and structural factors regulating cellular processes. The development of fluorescent nanoprobes represents a challenge to detect any cellular process under a microscope. Herein, a fluorescent nanomaterial was synthesized by exploiting the supramolecular interaction between a halochromic switch (1Cl) and halloysite nanotubes (HNTs). The successful synthesis of a HNTs/1Cl nanomaterial was confirmed by thermogravimetric analysis and Fourier transform infrared. The aqueous mobility was investigated by dynamic light scattering and ζ-potential measurements as well. Furthermore, …

NAIP-deltaEx10-11: a novel splice variant of the apoptosis inhibitor NAIP differently expressed in drug-sensitive and multidrug-resistant HL60 leukemia cells.

Alterations of neuronal apoptosis inhibitory protein (NAIP), a member of the inhibitory of apoptosis protein (IAP) family of inhibitors of apoptosis, have been previously associated with different neurodegenerative disorders. This study indicated the existence of a novel NAIP splice variant. This isoform, NAIP-deltaEx10-11, was found in tumor cell lines of different origin and in normal adult brain. Analysis of the putative protein predicted that the NAIP variant lacks part of the third BIR domain as well as the COOH-terminal tail of regular NAIP. This might suggest that it is endowed with a reduced antiapoptotic activity. This view is supported by the fact that NAIP-deltaEx10-11 mRNA and p…

Significance of Autologous Interleukin-6 Production in the HA22T/VGH Cell Model of Hepatocellular Carcinoma

Cancer cells may often support their own growth, survival, and drug resistance by autocrine/paracrine loops based on the production of different factors; results from us and others have shown that similar interleukin-6 (IL-6)-related loops are operative in multiple myeloma and prostate or renal cancer. Because this aspect has not been investigated in detail for hepatocellular carcinoma (HCC), we have examined it in HA22T/VGH cells. These differ from other primary liver cancer cell lines (that is, HepG2, HuH-6, and HuH-7) in that enzyme-linked immunosorbent assay (ELISA) showed the HA22T/VGH cells to secrete remarkable amounts of IL-6 (16.8 ng/10(6) cells/24 h); this production, due to const…

Brief Biography of Professor Natale D’Alessandro Dedicated in His Memory

Preface: Focus on the Main Research Interests of Professor Natale D’Alessandro

Epigenetic changes and nuclear factor-κB activation, but not microRNA-224, downregulate Raf-1 kinase inhibitor protein in triple-negative breast cancer SUM 159 cells

Raf-1 kinase inhibitor protein (RKIP) is a tumor suppressor and metastasis inhibitor, which enhances drug-induced apoptosis of cancer cells. Downregulation of RKIP may be significant in the biology of highly aggressive and drug-resistant tumors, for example triple-negative breast cancers (TNBCs). Potential causes for the low levels of RKIP expressed by SUM 159 TNBC cells were investigated in the present study. Bisulphite modification, methylation specific-polymerase chain reaction (PCR) and a TransAM NF-κB assay were performed and the results suggested that various mechanisms, including methylation of the gene promoter, histone deacetylation and nuclear factor-κB (NF-κB) activation, but not…

Essential Oil Composition of Alluaudia procera and in Vitro Biological Activity on Two Drug-Resistant Models

Drug resistance is a major obstacle in antibiotic and antitumor chemotherapy. In response to the necessity to find new therapeutic strategies, plant secondary metabolites including essential oils (EOs) may represent one of the best sources. EOs in plants act as constitutive defenses against biotic and abiotic stress, and they play an important role in the pharmacology for their low toxicity, good pharmacokinetic and multitarget activity. In this context, natural products such as EOs are one of the most important sources of drugs used in pharmaceutical therapeutics. The aim of this paper was to identify the chemical composition of the essential oil of Alluaudia procera leaves, obtained by hy…

Expression of HIP/PAP mRNA in Human Hepatoma Cell Lines

The present study attempts to shed more light on the role of hepatocarcinoma-intestine-pancreas/pancreatic associated protein (HIP/PAP) in hepatoma cells. We initially examined, by reverse transcription-polymerase chain reaction (RT-PCR), the HIP/PAP transcripts present in human hepatoma cell lines of different origins and with different grades of differentiation and genetic profiles. We also used DNA sequencing analysis to investigate the structure of the HIP/PAP gene. Further investigation is necessary to define the role of HIP/PAP during the development of human hepatocellular carcinoma and to ascertain whether the use of different transcripts is helpful in regulating HIP/PAP expression …

Cancer therapy and treatments during COVID-19 era

The COVID-19 pandemic has put a serious strain on health treatments as well at the economies of many nations. Unfortunately, there is not currently available vaccine for SARS-Cov-2/COVID-19. Various types of patients have delayed treatment or even routine check-ups and we are adapting to a virtual world. In many cases, surgeries are delayed unless they are essential. This is also true with regards to cancer treatments and screening. Interestingly, some existing drugs and nutraceuticals have been screened for their effects on COVID-19. Certain FDA approved drugs, vitamin, natural products and trace minerals may be repurposed to treat or improve the prevention of COVID-19 infections and disea…

Bioactive triterpenes of protium heptaphyllum gum resin extract display cholesterol-lowering potential

Hypercholesterolemia is one of the major causes of cardiovascular disease, the risk of which is further increased if other forms of dyslipidemia occur. Current therapeutic strategies include changes in lifestyle coupled with drug administration. Statins represent the most common therapeutic approach, but they may be insufficient due to the onset of resistance mechanisms and side effects. Consequently, patients with mild hypercholesterolemia prefer the use of food supplements since these are perceived to be safer. Here, we investigate the phytochemical profile and cholesterol-lowering potential of Protium heptaphyllum gum resin extract (PHE). Chemical characterization via HPLC-APCI-HRMS2 and…

Recovery of Bioactive Compounds from Marine Organisms: Focus on the Future Perspectives for Pharmacological, Biomedical and Regenerative Medicine Applications of Marine Collagen

Marine environments cover more than 70% of the Earth’s surface and are among the richest and most complex ecosystems. In terms of biodiversity, the ocean represents an important source, still not widely exploited, of bioactive products derived from species of bacteria, plants, and animals. However, global warming, in combination with multiple anthropogenic practices, represents a serious environmental problem that has led to an increase in gelatinous zooplankton, a phenomenon referred to as jellyfish bloom. In recent years, the idea of “sustainable development” has emerged as one of the essential elements of green-economy initiatives; therefore, the marine environment has been re-evaluated …

Chemical Composition, In Vitro Antitumor and Pro-Oxidant Activities of Glandora rosmarinifolia (Boraginaceae) Essential Oil

The biological properties of essential oils have been demonstrated in the treatment of several diseases and to enhance the bioavailability of other drugs. In natural habitats the essential oils compounds may play important roles in the protection of the plants as antibacterials, antivirals, antifungals, insecticides and also against herbivores by reducing their appetite for such plants or by repelling undesirable others. We analyzed by gas-chromatography mass spectrometry the chemical composition of the essential oil of aerial parts of Glandora rosmarinifolia (Ten.) D.C. Thomas obtained by hydrodistillation and verified some biological activities on a panel of hepatocellular carcinoma cell …

Antitumor effects of curcumin, alone or in combination with cisplatin or doxorubicin, on human hepatic cancer cells. Analysis of their possible relationship to changes in NF-kB activation levels and in IAP gene expression.

The hepatic cancer HA22T/VGH cell line, which constitutively expresses activated nuclear factor-kappaB (NF-kB), was chosen as a model to examine the antitumor activity of curcumin, also in relationship to its possible influences on the activation of the transcription factor and on the expression of the inhibitory of apoptosis proteins (IAPs) and of other NF-kB target genes. Curcumin exerted cell growth inhibitory and apoptotic effects, related, at least part, to free radical generation and mainly dependent on caspase-9 and -3 activation. The combination of curcumin with cisplatin resulted in a synergistic antitumor activity and that with doxorubicin in additivity or sub-additivity. Curcumin…

Product of aromatase activity in intact LNCaP and MCF-7 human cancer cells

We investigated conversion rates of androgens to estrogens in cultured, hormone-responsive prostate (LNCaP) and breast (MCF-7) human cancer cells. For this purpose, we adopted an intact cell analysis, whereby cells were incubated for different incubation times in the presence of close-to-physiological (1 nM) or supraphysiological (1 μM) concentrations of labelled androgen precursors, i.e. testosterone (T) and androstenedione (Δ4Ad). The aromatase activity, as measured by estrogen formation, was detected in LNCaP cells (0.5 pmol/ml), even though to a significantly lower extent than in MCF-7 cells (5.4 pmol/ml), using 1 μM T after 72 h incubation. Surprisingly, LNCaP cells displayed a much hi…

Antitumor Effect of Glandora rosmarinifolia (Boraginaceae) Essential Oil through Inhibition of the Activity of the Topo II Enzyme in Acute Myeloid Leukemia

It was previously shown that the antitumor and cytotoxic activity of the essential oil (EO) extracted from the aerial parts of Glandora rosmarinifolia appears to involve a pro-oxidant mechanism in hepatocellular carcinoma (HCC) and in triple-negative breast cancer (TNBC) cell lines. Its most abundant compound is a hydroxy-methyl-naphthoquinone isomer. Important pharmacological activities, such as antitumor, antibacterial, antifungal, antiviral and antiparasitic activities, are attributed to naphthoquinones, probably due to their pro-oxidant or electrophilic potential; for some naphthoquinones, a mechanism of action of topoisomerase inhibition has been reported, in which they appear to act b…

Curcumin as a possible lead compound against hormone-independent, multidrug-resistant breast cancer

We examine the possible evidence that the phytochemical curcumin may overcome resistance to hormonal and cytotoxic agents in breast cancer. We present our observations on MCF-7R, a multidrug-resistant (MDR) variant of the MCF-7 breast cancer cell line. In contrast to MCF-7, MCF-7R lacks aromatase and estrogen receptor alpha (ERalpha) and overexpresses the multidrug transporter ABCB1 and the products of different genes implicated in cell proliferation and survival, like c-IAP-1, NAIP, survivin, and COX-2. Nevertheless, in cytotoxicity and cell death induction assays, we found that the antitumor activity of curcumin is substantial both in MCF-7 and in MCF-7R. We elaborated the diketone system…

Synthesis of curcumin derivatives and analysis of their antitumor effects in triple negative breast cancer (TNBC) cell lines

We analyzed antitumor effects of a series of curcumin analogues. Some of them were obtained by reaction of substitution involving the two phenolic OH groups of curcumin while the analogues with a substituent at C-4 was prepared following an original procedure that regards the condensation of benzenesulfenic acid onto the nucleophilic central carbon of the curcumin skeleton. We analyzed cytotoxic effects of such derivatives on two TNBC (triple negative breast cancer) cell lines, SUM 149 and MDA-MB-231, but only three of them showed an IC50 in a lower micromolar range with respect to curcumin. We also focused on these three derivatives that in both cell lines exhibited a higher or at least eq…

Circulating IL-6 and sIL-6R in patients with hepatocellular carcinoma

Interleukin-6 plays a central role in regulating the immune system, hematopoiesis, and acute phase reaction. It interacts with a receptor complex consisting of a specific ligand-binding protein (IL-6R, gp80) and a signal transduction protein (gp130). In this report, serum levels of IL-6 and a soluble form of the interleukin-6 receptor (sIL-6R) were evaluated in patients with hepatocellular carcinoma. The correlation between IL-6 and sIL-6R values, the stage of hepatocellular carcinoma, and main liver function tests was also studied.

“Antitumor effects of curcumin in human hepatic cancer cells: Analysis of their relationship to inhibition of NF-kB and pro-survival gene expression”.

Antitumor Mechanism of the Essential Oils from Two Succulent Plants in Multidrug Resistance Leukemia Cell

Drug resistance remains a major challenge in the treatment of cancer. The multiplicity of the drug resistance determinants raises the question about the optimal strategies to deal with them. Essential oils showed to inhibit the growth of different tumor cell types. Essential oils contain several chemical classes of compounds whose heterogeneity of active moieties can help prevent the development of drug resistance. In the present paper, we analyzed, by gas chromatography-mass spectrometry the chemical composition of the essential oil of the leaves of Kalanchoe beharensis obtained by hydrodistillation and compared the chemical composition of its essential oil with that of Cyphostemma juttae.…

Patterns of Innate or Acquired Resistance to Anticancer Drugs: Our Experience to Overcome It

Drug resistance, which is often of a multiple type, can be defined as the ability of cancer cells to obtain resistance to both conventional and novel chemotherapy agents. It remains a major problem to solve in cancer therapy. The mechanisms of resistance are multifactorial, and in our cellular models of acute myeloid leukemia, hepatocellular carcinoma, and triple-negative breast cancer, it involves the NF-κB pathway. In our opinion, multitarget molecules can be considered as privileged compounds capable of attacking and reversing the resistant phenotype. In the phenomena of both innate and acquired drug resistance that we have been studying since 1998 to today and up to 2016 under the guida…

The antitumor activities of curcumin and its isoxazole analogue are not affected by multiple gene expression changes in an MDR model of the MCF-7 brest cancer cell line: Analysis of the possible molecular basis.

We examined the effects of curcumin and of its isoxazole analogue MR 39 in the MCF-7 breast cancer cell line and in its multidrug-resistant (MDR) variant MCF-7R. In comparison with MCF-7, MCF-7R lacks estrogen receptor alpha (ERalpha) and overexpressess P-glycoprotein (P-gp), different IAPs (inhibitory of apoptosis proteins) and COX-2. Through analyses of the effects on cell proliferation, cycling and death, we have observed that the antitumor activity of curcumin and of the more potent (approximately two-fold) MR 39 is at least equal in the MDR cell line compared to the parental MCF-7. Similar results were observed also in an MDR variant of HL-60 leukemia. RT-PCR evaluations performed in M…

Essential oil of Cyphostemma juttae (Vitaceae): Chemical composition and antitumor mechanism in triple negative breast cancer cells

The genus Cyphostemma (Planch.) Alston (Vitaceae) includes about 150 species distrib- uted in eastern and southern Africa and Madagascar. Some species are used in traditional medicine and their biological activities, including antiproliferative effects against cancer cell lines, have been demonstrated. To date no investigations on Cyphostemma essential oils have been carried out. Essential oils, which play important roles in plant defenses have been demonstrated to be active in the treatment of several human diseases and to enhance bioavability of other drugs. The aim of this paper was to identify the chemical composition of the essential oil of the leaves of Cyphostemma juttae (Dinter &amp…

Antitumor effects of curcumin and structurally β-diketone modified analogs on multidrug resistant cancer cells

Abstract Using concepts of bioisostery a series of curcumin analogs were synthesized: the diketonic system of the compound was elaborated into enaminones, oximes, and the isoxazole heterocycle. The cell growth inhibitory and apoptosis inducing effects of the new analogs were evaluated by in vitro assays in the hepatocellular carcinoma HA22T/VGH cells, as well as in the MCF-7 breast cancer cell line and in its multidrug resistant (MDR) variant MCF-7R. Increased antitumor activity on all cell lines was found with the isoxazole analog and especially with the benzyl oxime derivative; in the HA22T/VGH cell model, the latter compound inhibited constitutive NF-κB activation.

Lack of nucleophilic addition in the isoxazole and pyrazole diketone modified analogs of curcumin; implications for their antitumor and chemosensitizing activities.

Curcumin (CUR) can be considered as a good lead compound for the design of new anticancer drugs. Further, structure-activity relationship studies may clarify the importance of the redox activities in the antitumor effects of the drug. We have elaborated the alpha,beta-unsaturated 1,3-diketone moiety of CUR into the isoxazole (ISO) and pyrazole (PYR) derivatives. These derivatives should be much less prone to nucleophilic addition than CUR and benzyl mercaptan addition analyses showed that indeed they do not form isolable conjugated products. When compared with CUR, ISO and PYR exhibited increased cell growth inhibitory and pro-apoptotic effects in liver cancer HA22T/VGH cells as well as in …

In Vitro Modulation of P-Glycoprotein Activity by Euphorbia intisy Essential Oil on Acute Myeloid Leukemia Cell Line HL-60R

Euphorbia species have a large spectrum of traditional medicinal uses. We tested the biological activities of the essential oil (EO) of Euphorbia intisy Drake in an acquired multidrug resistance leukemia model to assess whether the EO obtained by hydrodistillation of stems was able to reverse the resistant phenotype. HL-60R cell lines are characterized by the overexpression of P-glycoprotein (P-gp), inhibitors of apoptosis proteins (IAPs) and constitutive expression of NF-κB. EO chemical composition was determined by GC/MS analysis

Induction of Apoptosis and Chemosensitization by the Histone Deacetylase Inhibitor Trichostatin in Hepatocellular Carcinoma Cells: Molecular Analysis and RKIP Levels

The mRNA and protein levels of RKIP are reduced and those of YY1 increased in clinical HCC. Loss, mutation, or promoter hypermethylation of the RKIP gene may not account for the downregulation of RKIP in HCC. Histone deacetylation can silence gene expression and play a significant role in hepatocarcinogenesis. The histone deacetylase inhibitor (HDACI) trichostatin induced cell growth inhibition and proapoptotic effects in HA22T/VGH and HepG2 HCC cells; it also exhibited synergy with doxorubicin. Treatment with trichostatin caused histone hyperacetylation and down- or upregulated expression of different genes (such as β-catenin, cyclin D1, hTERT, XIAP, and IL-6). These changes might, at leas…

Potential Therapeutic Applications of MDA-9/Syntenin-NF-κB-RKIP Loop in Human Liver Carcinoma

Background Overexpression of MDA-9/Syntenin occurs in multiple human cancer cell lines and is associated with higher grade of tumor classification, invasiveness and metastasis. In some cases, its role in cancer biology depends on relationships between MDA-9/Syntenin and NF-κB. Objective This study aims to analyze the presence of a regulation loop like that between MDA-9/Syntenin - NF-κB - RKIP in human liver carcinoma. Methods Transient transfection was performed with siRNA anti-MDA-9/Syntenin. Expression of different factors was evaluated by Real time-PCR and Western blotting, while NF-κB activation by TransAM assay. Invasion capacity was analyzed by Matrigel Invasion Assay and the effects…

Abilities of β-Estradiol to interact with chemotherapeutic drugs, signal transduction inhibitors and nutraceuticals and alter the proliferation of pancreatic cancer cells.

Improving the effects of chemotherapy and reducing the side effects are important goals in cancer research. Various approaches have been examined to enhance the effectiveness of chemotherapy. For example, signal transduction inhibitors or hormonal based approaches have been included with chemo- or radio-therapy. MIA-PaCa-2 and BxPC-3 pancreatic ductal adenocarcinoma (PDAC) cells both express the estrogen receptor (ER). The effects of β-estradiol on the growth of PDAC cells has not been examined yet the ER is expressed in PDAC cells. We have examined the effects of combining β-estradiol with chemotherapeutic drugs, signal transcription inhibitors, natural products and nutraceuticals on PDAC.…

Truncated Form of beta-Catenin and Reduced Expression of Wild-Type Catenins Feature HepG2 Human Liver Cancer Cells

Phytol and Heptacosane Are Possible Tools to Overcome Multidrug Resistance in an In Vitro Model of Acute Myeloid Leukemia

Drug resistance is the ability of cancer cells to gain resistance to both conventional and novel chemotherapy agents, and remains a major problem in cancer therapy. Resistance mechanisms are multifactorial and involve more strictly pharmacological factors, such as P-glycoprotein (P-gp) and biological factors such as inhibitor of apoptosis proteins (IAPs) and the nuclear factor-kappa B (NF-κB) pathway. Possible therapeutic strategies for the treatment of acute myeloid leukemia (AML) have increased in recent years; however, drug resistance remains a problem for most pa-tients. Phytol and heptacosane are the major compounds of Euphorbia intisy essential oil (EO) which were demonstrated to inhi…

Synthesis, In Vitro and In Silico Analysis of New Oleanolic Acid and Lupeol Derivatives against Leukemia Cell Lines: Involvement of the NF-κB Pathway

Oleanolic acid (OA) and Lupeol (LU) belong to the class of natural triterpenes and are endowed with a wide range of biological activities, including cytotoxicity toward several cancer cell lines. In this context, we investigated a set of compounds obtained from the two natural precursors for the cytotoxicity against leukemia HL60 cells and the multidrug-resistant (MDR) variant HL60R. Six new semi-synthetic triterpenes have been synthetized, fully characterized, and were investigated together with other triterpenes compounds for their pharmacological mechanism of action. The interaction of the more cytotoxic compounds with the nuclear factor kappa B (NF-κB) pathway has been also evalua…

NF-κB Inhibition Restores Sensitivity to Fas-Mediated Apoptosis in Lymphoma Cell Lines

Failure to perform the Fas-related apoptosis pathway can account for tumor resistance both to chemotherapeutic agents and to immunological effectors. We studied the role of NK-kappaB in Fas-resistance, employing the Fas-sensitive human T-lymphoma HuT78 cell line and its Fas-resistant variants HuT78B1 and HuT78G9. All these cell lines expressed high levels of constitutively activated NF-kappaB. Pretreatment of cells with NF-kappaB inhibitors (PDTC, MG132, or SN50) strongly enhanced CH11-induced apoptosis in HuT78 and Hut78G9 cells, while only MG132 showed a similar potentiating effect in HuT78B1. The described synergism was significantly inhibited by pretreatment with the anti-Fas-blocking a…

Cytotoxicity of oleanolic and ursolic acid derivatives toward hepatocellular carcinoma and evaluation of NF-κB involvement.

Oleanolic and ursolic acids are two ubiquitous isomeric triterpene phytochemicals known for their anticancer activity. A set of derivatives of the two compounds with a modified oxidation state and lipophylicity at C-3 and C-28 positions, were prepared and tested as anticancer agents versus the lines HepG2, Hep3B and HA22T/VGH of hepatocarcinoma, a strongly aggressive tumor that is not responsive toward the standard therapies. New derivatives containing a three carbons side chain on the C-3 position were synthetized in both stereoisomeric forms by the Barbier-Grignard procedure and three of them were found to be active toward all of the three targets. The implication of the transcriptional n…

MDA-9/Syntenin-NF-κB-RKIP loop in triple negative breast cancers (TNBC) and human liver carcinoma

We analyzed the presence of a regulation loop like that between MDA-9/Syntenin - NF-κB - RKIP in three TNBC cell lines (SUM 149, SUM 159 and MDA-MB-231) and in three cell lines of human liver carcinoma (HA22T/VGH, Hep3B and HepG2). Both these cancers are characterized by high aggressive phenotype, poor prognosis and few therapeutic possibilities. Transient transfection was performed with siRNA anti-MDA-9/Syntenin. Expression of different factors was evaluated by Real time-PCR and Western blotting, while NF-κB activation by TransAM assay. Invasion capacity was analyzed by Matrigel Invasion Assay. We observed that silencing of MDA-9/Syntenin expression by anti-MDA-9/Syntenin siRNA induced NF-…

Influence of CYP3A5 and ABCB1 gene polymorphisms and other factors on tacrolimus dosing in Caucasian liver and kidney transplant patients

Tacrolimus is a substrate of cytochrome P4503A (CYP3A) enzymes as well as of the drug transporter ABCB1. We have investigated the possible influence of CYP3A5 and ABCB1 single nucleotide polymorphisms (SNPs) and other factors (e.g. albumin, hematocrit and steroids) on tacrolimus blood levels achieved in a population of Caucasian liver (n=51) and kidney (n=50) transplant recipients. At 1, 3 and 6 months after transplantation, tacrolimus doses (mg/kg/day) and trough blood levels (C0) were recorded and the weight-adjusted tacrolimus dosage (mg/kg/day) was calculated. Polymerase chain reaction followed by restriction fragment length polymorphism analysis was used for genotyping CYP3A5*1 and *3 …