Hepatotoxicity caused by mebendazole in a patient with Gilbert's syndrome

What is known and objective Mebendazole (MBZ) is a broad-spectrum antihelminthic agent of the benzimidazole type. Although MBZ has been reported to cause hepatic injury, case reports of severe hepatic injury are very rare. We report a case of severe hepatitis after administration of MBZ in a patient with Gilbert's syndrome affected by pinworms infestation. Case summary Differently from other cases of hepatitis due to MBZ reported in the scientific literature, our patient received standard doses of MBZ for a short period of time. After 18 days from the start of therapy, he developed hepatomegaly, and increases in hepatic enzymes and bilirubin. Hepatic enzymes returned to normal over the foll…

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.

Meccanismi di resistenza ai farmaci antitumorali

Nonostante i progressi della terapia medica dei tumori solidi e del sangue, la resistenza ai farmaci antineoplastici rimane un ostacolo principale alla guarigione di molti pazienti.Le cause di tale resistenza sono molteplici e possono essere inizialmente distinte in "farmacologiche" e "cellulari."

Farmacovigilanza attiva sul ruolo dei farmaci antiangiogenetici nell’osteonecrosi dei mascellari

Farmacovigilanza attiva sul ruolo dei farmaci antiangiogenetici nell’osteonecrosi dei mascellari Ilaria Morreale1, Maria Meli1, Olga Di Fede2, Giuseppina Campisi2, Natale D’Alessandro1 1Centro di consulenza sulle reazioni avverse da farmaci in oncologia della Regione Sicilia – U.O.C. di Farmacologia Clinica e 2Gruppo P.R.O.Ma.B. (Prevenzione e Ricerca sull’Osteonecrosi dei Mascellari da Bisfosfonati) - Settore di Medicina Orale "Valerio Margiotta" - AOUP “P. Giaccone” di Palermo Obiettivi L’uso dei bisfosfonati (BP) in oncologia e anche nell’osteoporosi è stato definitivamente associato ad una complicazione relativamente rara ma grave come l’osteonecrosi dei mascellari (ONJ). La patogenesi …

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…

alpha-Glycerophosphocholine in the mental recovery of cerebral ischemic attacks. An Italian multicenter clinical trial.

The clinical efficacy and the tolerability of alpha-glycerophosphocholine (alpha-GPC), a drug able to provide high levels of choline for the nervous cells of the brain and to protect their cell walls, have been tested in a clinical open multicenter trial on 2044 patients suffering from recent stroke or transient ischemic attacks. alpha-GPC was administered after the attack at the daily dose of 1000 mg im for 28 days and orally at the dose of 400 mg tid during the following 5 months after the first phase. The evaluation of the efficacy on the psychic recovery was done by the Mathew Scale (MS) during the period of im drug administration, and using the Mini Mental State Test (MMST), the Cricht…

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…

Farmaci antimicrotubulari

Farmaci antimicrotubulari

New trends in overcoming drug resistance in hepatocellular carcinoma. Looking for pharmacological inhibition of Inhibitory of Apoptosis Proteins (IAPs) by curcumin.

Expression of IAPs (Inhibitory of Apoptosis Proteins) and of their 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.

Galangin increases the cytotoxic activity of imatinib mesylate in imatinib-sensitive and imatinib-resistant Bcr-Abl expressing leukemia cells

Resistance to imatinib mesylate is an emergent problem in the treatment of Bcr-Abl expressing myelogenous leukemias and additional therapeutic strategies are required. We observed that galangin, a non-toxic, naturally occurring flavonoid was effective as anti-proliferative, and apoptotic agent in Bcr-Abl expressing K562 and KCL22 cells and in imatinib mesylate resistant K562-R and KCL22-R cells. Galangin induced an arrest of cells in G0–G1phase of cell cycle and a decrease in pRb, cdk4, cdk1, cycline B levels; moreover, it was able to induce a monocytic differentiation of leukemic Bcr-Abl+ cells. Of note, galangin caused a decrease in Bcl-2 levels and markedly increased the apoptotic activi…

“Effects of combretastatin analogues on leukemic cell lines and normal hemopoietic cells”

From the covalent linkage of drugs to novel inhibitors of ribonucleotide reductase: synthesis and biological evaluation of valproic esters of 3'-C-methyladenosine

We synthesized a series of serum-stable covalently linked drugs derived from 3'-C-methyladenosine (3'-Me-Ado) and valproic acid (VPA), which are ribonucleotide reductase (RR) and histone deacetylase (HDAC) inhibitors, respectively. While the combination of free VPA and 3'-Me-Ado resulted in a clear synergistic apoptotic effect, the conjugates had lost their HDAC inhibitory effect as well as the corresponding apoptotic activity. Two of the analogs, 2',5'-bis-O-valproyl-3'-C-methyladenosine (A160) and 5'-O-valproyl-3'-C-methyladenosine (A167), showed promising cytotoxic activities against human hematological and solid cancer cell lines. A167 was less potent than A160 but had interesting featu…

Farmaci antimicrotubulari.

The new iodoacetamidobenzofuran derivative TR120 decreases STAT5 expression and induces antitumor effects in imatinib-sensitive and imatinib-resistant BCR-ABL-expressing leukemia cells

The identification of novel compounds modulating the expression/activity of molecular targets downstream to BCR-ABL could be a new approach in the treatment of chronic myeloid leukemias (CMLs) resistant to imatinib or other BCR-ABL-targeted molecules. Recently, we synthesized a new class of substituted 2-(3,4,5-trimethoxybenzoyl)-2-N,N-dimethylamino-benzo[b]furans, and among these 3-iodoacetylamino-6-methoxybenzofuran-2-yl(3,5-trimethoxyphenyl)methanone (TR120) showed marked cytotoxic activity in BCR-ABL-expressing cells. Interestingly, TR120 was more potent than imatinib in cell growth inhibition and apoptosis induction in both BCR-ABL-expressing K562 and KCL22 cells. Moreover, it showed a…

Programmed cell death (PCD) associated with the stilbene motif of arotinoids: discovery of novel apoptosis inducer agents possessing activity on multidrug resistant tumor cells

Considering that the stereochemistry of the C9-C10 alkenyl portion of natural 9-cis-RA, as the one of the olefinic moiety of the previously described isoxazole retinoid 4, seems of particular importance for their apoptotic activity, we prepared a novel class of TTNPB analogues bearing both the cis or trans configuration of the alkenyl portion. The compounds were evaluated in vitro for their cytotoxic and apoptotic activities. We discovered that the cis-TTNPB 9c possesses apoptotic activity comparable with that of the retinoid 4. Moreover, the amino arotinoid 16c showed potent apoptotic activity in HL60 promyelocytic leukemia cells. Interestingly, 16c proved to be a particularly potent apopt…

Meccanismi di resistenza ai farmaci antitumorali.

Meccanismi di resistenza ai farmaci antitumorali.

Histone deacetylase (HDAC) inhibitors potentiate the antiproliferative and apoptotic effects induced by the novel ribonucleotide reductase (RR) inhibitor 3'-metil-adenosine (3'-Me-Ado) in promyelocitic leukemia cell lines

Multidrug resistance reverting activity and antitumor profile of new phenothiazine derivatives

Abstract A series of easily affordable phenothiazine derivatives bearing a rigid but-2-ynyl amino side chain were synthesized and tested to evaluate the MDR reverting activity and full antitumor profile. Some compounds endowed with remarkable MDR reverting effect were identified, and the most active one ( 6c ) was shown to increase doxorubicin retention in multidrug resistant cells, suggesting a direct interaction with P-glycoprotein. Furthermore, a broad range of cellular activities were observed for different compounds. In particular, the ability of some derivatives to induce antiproliferative effects on resistant cell lines and to interfere with the G 1 phase of the cell cycle, a phase u…

A Phase II Trial of Mitoxantrone plus Cyclophosphamide and 5-Fluorouracil in Modulation with Levo-Folinate for Advanced Breast Cancer Patients

Advanced breast cancer remains a major clinical problem. Current chemotherapy regimens are able to induce a clinical response in many patients but do not appear to influence significantly patients' survival. The use of new drugs such as mitoxantrone with a predicted lower toxicity and biochemical modulation of 5-fluorouracil with levo-folinate are extensively studied research areas that could combine good therapeutic efficacy with the maintenance of an acceptable quality of life. 34 patients with advanced breast carcinoma were included in the study. Only 4 women had received prior chemotherapy for advanced disease. Treatment plan was: 5-fluorouracil 400 mg/m2 + l-leucovorin 100 mg/m2 days 1…

The use of proton pump inhibitors in an Italian hospital: focus on oncologic and critical non-ICU patients

Background Proton pump inhibitors (PPIs) are among the most misused drugs both at the community and hospital level. Recently, possible risks have been underscored, suggesting the importance of limiting PPI use to proven indications. Objective To survey the appropriateness of PPI use in a University hospital in Italy. Setting Azienda Ospedaliera Universitaria Policlinico ‘P. Giaccone’, in Palermo, Italy. Method A one day-observational study, reviewing patients’ medical records to identify treatments with PPIs and the indications for their use. After discharge, a subgroup of the cohort was followed up to assess the continuation of therapy at home. Appropriateness was evaluated according to th…

The use of low molecular weight heparin in a Sicilian teaching hospital

LMWH are replacing unfractionated heparin (UFH) for therapeutic anticoagulation owing to their more predictable pharmacokinetics and ease of use. Especially in Sicily, their prescription volume is steadily increasing in general practice, but little is known about their use in the hospital setting. We investigated LMWH use at the Policlinico Universitario P. Giaccone of Palermo by examining the records of drug dispensation to the wards in the years 2010-2012. From 2010 to 2012 the use of LMWH at Policlinico of Palermo remained stable with a mean of 71 DDD/100 bed days (range 69-73) of drugs dispensed. Enoxaparin, nadroparin and reviparin were the most prescribed molecules, accounting each on…

Hydroxamic acid-containing histone deacetylase inhibitors potentiate the antiproliferative and apoptotic effects induced by the ribonucleotide reductase R1 inhibitor 3'-C-methyl-adenosine in promyelocytic leukemia cell lines

The synergistic apoptotic effects of thiophenfurin, an inosine monophosphate dehydrogenase inhibitor, in combination with retinoids in HL60 cells

New effective cytotoxic agents and combinations are urgently needed in cancer treatment. The enzyme inosine monophosphate dehydrogenase is a potentially useful target for drug development, since its activity has been shown to be amplified in malignant cells. Thiophenfurin, an inhibitor of the enzyme synthesized by us, is endowed with a significant apoptotic activity in promyelocytic leukaemia HL60 cells. Since retinoids were successfully employed in the treatment of patients with leukaemia, demonstrating significant differentiation-inducing and apoptotic effects, we carried out this study to evaluate the effects of the combination of thiophenfurin and several retinoid molecules, acting in d…

Inhibition of activated STAT5 in Bcr/Abl expressing leukemia cells with new pimozide derivatives.

STATs are transcription factors acting as intracellular signaling after stimulation with cytokines, growth factors and hormones. STAT5 is also constitutively active in many forms of cancers, including chronic myelogenous leukemia, acute lymphoblastic leukemia and Hodgkin's lymphoma. Recently, literature reported that the neuroleptic drug pimozide inhibits STAT5 phosphorylation inducing apoptosis in CML cells. We undertook an investigation from pimozide structure, obtaining simple derivatives with cytotoxic and STAT5-inhibitory activity, two of them markedly more potent than pimozide.

Novel iodoacetamido benzoheterocyclic derivatives with potent antileukemic activity are inhibitors of STAT5 phosphorylation

Signal Transducer and Activator of Transcription 5 (STAT5) protein, a component of the STAT family of signaling proteins, is considered to be an attractive therapeutic target because of its involvement in the progression of acute myeloid leukemia. In an effort to discover potent molecules able to inhibit the phosphorylation-activation of STAT5, twenty-two compounds were synthesized and evaluated on the basis of our knowledge of the activity of 2-(3’,4’,5’-trimethoxybenzoyl)-3-iodoacetamido-6-methoxy benzo[b]furan derivative 1 as a potent STAT5 inhibitor. Most of these molecules, structurally related to compound 1, were characterized by the presence of a common 3’,4’,5’-trimethoxybenzoyl moi…

4,5,6,7-Tetrahydro-isoxazolo-[4,5-c]-pyridines as a new class of cytotoxic Hsp90 inhibitors.

Hsp90 is considered an interesting therapeutic target for anticancer drug development. Here we describe a new class of 4,5,6,7-tetrahydro-isoxazolo-[4,5-c]-pyridine compounds. A small library of derivatives has been synthesized and investigated. Some reported compounds show interesting properties combining both notable binding to Hsp90 and potent cell growth inhibitory activity. N-5 substitution with a 2,4 resorcinol carboxamide appears crucial for activity. Moreover, a derivative bearing a hydroxamic acid residue bound to C-3 amide portion was found to inhibit both Hsp90 and HDAC6.

Histone deacetylase inhibition modulates deoxyribonucleotide pools and enhances the antitumor effects of the ribonucleotide reductase inhibitor 3’-C-methyladenosine in leukaemia cells

Histone deacetylase (HDAC) inhibitors are a new class of epigenetic agents that were reported to enhance the cytotoxic effects of classical anticancer drugs through multiple mechanisms. However, which of the possible drug combinations would be the most effective and clinically useful are to be determined. We treated the HL60 and NB4 promyelocytic leukaemia cells with a combination of the ribonucleotide reductase (RR) inhibitor 3'-C-methyladenosine (3'-Me-Ado) and several hydroxamic acid-derived HDAC inhibitors, including two recently synthesized molecules, MC1864 and MC1879, and the reference compound trichostatin A (TSA). The results showed significant growth inhibitory and apoptotic syner…

Uso degli inibitori di pompa protonica in un Policlinico Universitario

Summary Introduction Proton pump inhibitors (PPIs) are highly prescribed drugs in Italy and in particular in the Sicilian region but little is known about their use in the hospital setting. Materials and methods PPI utilization and related costs were reviewed retrospectively by examining the pharmaceutical records of drug dispensation to the various wards of the Policlinico Universitario P. Giaccone of Palermo in 2010. Differences in the prescribing rates and drug preferences among the different clinical wards were analyzed. Results A total of 20,420 patients were hospitalized at the Policlinico of Palermo in 2010. Overall, the consumption of PPIs was 120 DDD/100 bed-days for the year 2010 …

Antitumor profile of new phenothiazine derivatives

Cyclophosphamide plus Epidoxorubicin and 5-Fluorouracil with Folinic Acid as a Novel Treatment in Metastatic Breast Cancer: Preliminary Results of a Phase II Study

Twenty consecutive patients with advanced breast cancer were treated with a combination of cyclophosphamide 600 mg/m2 i.v. on day 1, epidoxorubicin 75 mg/m2 on day 1, and 5-fluorouracil 375 mg/m2 i.v. with folinic acid 200 mg/m2 i.v. on days 1----3. The overall response rate was 60%, with 10% of patients showing a complete response with a mean duration of 11.1 + months, and 50% of patients a partial response of 7.4 + months. A stabilization of 5.2 + months was obtained in 20% of cases, while 20% of patients progressed. The most frequently observed toxicity was leukopenia, while expected mucosal toxicities were rather mild.

Heterocycle-containing retinoids. Discovery of a novel isoxazole arotinoid possessing potent apoptotic activity in multidrug and drug-induced apoptosis-resistant cells.

In a search for retinoic acid (RA) receptor ligands endowed with potent apoptotic activity, a series of novel arotinoids were prepared. Because the stereochemistry of the C9-alkenyl portion of natural 9-cis-RA and the olefinic moiety of the previously synthesized isoxazole retinoid 4 seems to have particular importance for their apoptotic activity, novel retinoid analogues with a restricted or, vice versa, a larger flexibility in this region were designed and prepared. The new compounds were evaluated in vitro for their ability to activate natural retinoid receptors and for their differentiation-inducing activity. Cytotoxic and apoptotic activities were, in addition, evaluated. In general, …

HISTONE DEACETYLASE (HDAC) INHIBITION MODULATES INTRACELLULAR DEOXYNUCLEOTIDES (DNTP) POOLS AND POTENTIATES THE ANTITUMOR EFFECTS OF THE RIBONUCLEOTIDE REDUCTASE (RR) INHIBITOR 3’- METHYL-ADENOSINE (3’-ME-ADO) IN PROMYELOCITIC LEUKAEMIA CELL LINES.

HDAC inhibitors are a new class of antitumor agents that were reported to enhance the cytotoxic effects of a number of classical anticancer drugs through multiple mechanisms. In particular, they are capable of modulating the expression of a series of key cellular genes leading to significant antiproliferative and apoptotic effects. However, which of the possible drug combinations would be the most effective and clinically useful is still to be determined. We treated the HL60 and NB4 promyelocitic leukaemia cells with a combination of the RR inhibitor 3’-Me-Ado and several hydroxamic acid–derived HDAC inhibitors, including the two recently synthesized molecules, MC1864 and MC1879, and the re…

Pterostilbene and 3′-hydroxypterostilbene are effective apoptosis-inducing agents in MDR and BCR-ABL-expressing leukemia cells

Pterostilbene and 3,5-hydroxypterostilbene are the natural 3,5-dimethoxy analogs of trans-resveratrol and piceatannol, two compounds which can induce apoptosis in tumor cells. In previous studies we demonstrated the importance of a 3,5-dimethoxy motif in conferring pro-apoptotic activity to stilbene based compounds so we now wanted to evaluate the ability of pterostilbene and 3,5-hydroxypterostilbene in inducing apoptosis in sensitive and resistant leukemia cells. When tested in sensitive cell lines, HL60 and HUT78, 3'-hydroxypterostilbene was 50-97 times more potent than trans-resveratrol in inducing apoptosis, while pterostilbene appeared barely active. However, both compounds, but not tr…

Heterocyclic and Phenyl Double-Bond-Locked Combretastatin Analogues Possessing Potent Apoptosis-inducing activity in HL60 and in MDR Cell lines

Two new series of combretastatin (CA-4) analogues have been prepared. The alkenyl motif of CA-4 was replaced either by a five-membered heterocyclic (isoxazoline or isoxazole) or by a six-membered ring (pyridine or benzene). The new compounds have been evaluated for their effects on tubulin assembly and for cytotoxic and apoptotic activities. Five compounds (18b, 20a, 21a, 34b, and 35b) demonstrated an attractive profile of cytotoxicity (IC501 microM) and apoptosis-inducing activity but poor antitubulin activity. The isoxazoline derivatives 18b, 20a, and 21a, demonstrated potent apoptotic activity different from that of natural CA-4. Their ability to block most cells in the G2 phase suggests…

Cytotoxic and apoptotic effects of thiophenfurin in combination with retinoids in human promyelocitic leucemia HL60 cells

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…

Antitumor effects of novel co-drugs linking histone deacetylase and ribonucleotide reductase inhibitors in hematological tumors

Combination therapy is the mainstay of anticancer therapy due to the significant synergistic effects achievable. Now that anticancer drug research turned toward a more molecular targeted approach, the design of dual-target drugs appears to be a new promising strategy with the potential to improve the therapeutic efficacy of the single drug and to reduce the probability of drug induced resistance and cross resistance. In our previous work, we found that 3’-C-methyl-adenosine (3’-Me-Ado), developed by us as a potent ribonucleotide reductase (RR) inhibitor with antitumor activity against both human leukemia and carcinoma cell lines, elicited significant growth inhibitory and apoptotic synergis…

Epigenetic agents as an adjunct to active chemotherapy in hematological tumor cell lines

Epigenetic therapy is a new promising area in cancer research that is based on the use of a series of molecules capable of affecting tumor cell growth, differentiation and death by modifying the cellular mechanisms underlying the control of gene expression. Significant enhancement of traditional anticancer drug effects has been also reported by several authors. Our recent research focused on the identification of new epigenetic agent-containing drug combinations to be employed in the therapy of leukemia. The results showed that the new combination of an histone deacetylase (HDAC) inhibitor and the ribonucleotide reductase (RR) inhibitor 3’-methyl-adenosine (3’-Me-Ado) is endowed with a sign…

STAT5 and STAT5 Inhibitors in Hematological Malignancies

The JAK-STAT pathway is an important physiologic regulator of different cellular functions including proliferation, apoptosis, differentiation, and immunological responses. Out of six different STAT proteins, STAT5 plays its main role in hematopoiesis and constitutive STAT5 activation seems to be a key event in the pathogenesis of several hematological malignancies. This has led many researchers to develop compounds capable of inhibiting STAT5 activation or interfering with its functions. Several anti-STAT5 molecules have shown potent STAT5 inhibitory activity in vitro. However, compared to the large amount of clinical studies with JAK inhibitors that are currently widely used in the clini…

The CD95/CD95 ligand system is not the major effector in anticancer drug-mediated apoptosis.

Many anticancer drugs are able to induce apoptosis in tumor cells but the mechanisms underlying this phenomenon are poorly understood. Some authors reported that the p53 tumor suppressor gene may be responsible for drug-induced apoptosis; however, chemotherapy-induced apoptosis can also be observed in p53 negative cells. Recently, doxorubicin (DXR) was reported to induce CD95L expression to mediate apoptosis through the CD95/CD95L system. Thus, an impairment of such a system may be involved in drug resistance. We evaluated the in vitro antitumor activity of several cytotoxic drugs on two human p53-negative T-cell lymphoma cell lines, the HUT78-B1 CD95L-resistant cell line and the HUT78 pare…

Effects of Pimozide Derivatives on pSTAT5 in K562 Cells

STAT5 is a transcription factor, a member of the STAT family of signaling proteins. STAT5 is involved in many types of cancer, including chronic myelogenous leukemia (CML), in which this protein is found constitutively activated as a consequence of BCR-ABL expression. The neuroleptic drug pimozide was recently reported to act as an inhibitor of STAT5 phosphorylation and is capable of inducing apoptosis in CML cells in vitro. Our research group has synthesized simple derivatives of pimozide with cytotoxic activity and that are able to decrease the levels of phosphorylated STAT5. In this work we continued the search for novel STAT5 inhibitors, synthesizing compounds in which the benzoimidazol…