0000000000612849
AUTHOR
Luciano Rausa
Kinetics of in vivo inhibition of tissue cathepsin d by pepstatin A
1. 1. We have investigated the kinetics of inhibition of cathepsin D in heart, liver and skeletal muscle of CD-1 mice following administration of 25, 50, 100 and 200 mg/kg i.p. of pepstatin A, a specific inhibitor of this protease. 2. 2. In the liver, a significant inhibition of cathepsin D occurred up to at least 15 days, whereas, in heart and skeletal muscle, this inhibition lasted for a much shorter period of time. 3. 3. These results show that the recovery of enzyme activity to normal values is dose-dependent and that, at the same dose level, marked differences occur in the recovery of enzyme activity in these organ tissues, the liver being the most sensitive one. © 1988.
RELATIONSHIP BETWEEN THE THYMIDYLATE SYNTHASE, p53 LEVELS AND THE TREATMENT BY CMF DRUG COMBINATION VERSUS TAXANES IN THE LOCALLY ADVANCED CARCINAMO OF THE BREAST
Combination chemotherapy with mitomycin C, vindesine and melphalan for refractory metastatic breast cancer.
A combination of mitomycin C, vindesine and melphalan was administered to 33 patients with heavily pretreated refractory breast cancer. The overall response rate was 27% with a mean duration of more than 10.2 months. A stabilization with a mean duration of 5.1 months was seen in 56% of cases, while 20% of patients progressed. Gastrointestinal toxicity, mostly grade 1 or 2 nausea/vomiting was seen in 85% of cases, grade 1 or 2 leukopenia in 60% of patients, and grade 1 or 2 thrombocytopenia in 42%. Considering the good compliance of this regimen and the poor prognosis of patients with refractory advanced breast cancer, this combination can be useful as a palliative treatment of breast carcin…
Thymidylate synthase polymorphism and microsatellite instability: association in colorectal cancer.
5-Fluorouracil (5FU) is the main drug used for the treatment of colorectal cancer (CRC) and Thymidilate Synthase (TS) is its target enzyme. TS gene has regulatory tandemly repeated sequences in its 5'' and 3''untraslated region (5''-3'' UTR). CRC often shows a kind of genomic instability called Microsatellite Instability (MSI) that is associated with TS levels and survival. Our data show that the genotype 2R/2R (homozygosity for 2 tandem repeat sequences in the 5''UTR) is more frequently associated with MSI+ and lower TS levels. More over we did not find any significant association between the 2R/3R (heterozygosity for 2 and 3 tandem repeat sequences in the 5''UTR) and 3R/3R (homozygosity f…
Erythromycin reverses the daunomycin resistance of MEL-DRTL cells
Low cell proliferation marker and low thymidylate synthase levels in the highly aggressive signet ring cell variant histotype of colorectal carcinoma
Does catalase play a role in Adriamycin induced cardiotoxicity?
Summary Adriamycin causes an increase of lipid peroxidation in mouse cardiac homogenates that is dependent on the concentration of the antiblastic. The same phenomenon is not observed in the hearts of mice treated with an elevated dose of Adriamycin in which, conversely, an increase of the antioxidizing enzyme catalase was noticed. The significance of these findings is discussed with relationship to the hypothesis of an enhanced free radicals formation at the basis of Adriamycin induced cardiotoxicity.
Difference in ki67 and Thimidylate Synthase expressin in primary tumour compared with metastatic nodes in breast cancer patients
Effects of verapamil and N-acetylcysteine on doxorubicin or isoproterenol cardiotoxicity in mice
Haemopoietic effects of 7 alpha, 17 beta dimethyltestosterone.
Some haematic parameters were investigated in female COBS mice treated with 7 alpha, 17 beta Dimethyltestcsterone (DMT). The drug causes an increase of circulating platelets in normal mice. Bone marrow graft from DMT-treated donors facilitates in irradiated mice repopulation of white blood cells and platelets but lowers % survival. These data are interpreted on the basis of a commitment and a loss of self-maintenance induced by DMT on CFUs compartment. © 1979 The Italian Pharmacological Society.
Antiproliferative and chemomodulatory effects of interferon-γ on doxorubicin-sensitive and -resistant tumor cell lines
Biological agents might offer various therapeutic opportunities in the treatment of cancer, including a direct and/or host-mediated antiproliferative effect and also the possibility to favorably modulate tumor resistance to antineoplastic drugs. We studied the in vitro antiproliferative effects of interferon (IFN)-gamma on the mouse B16 melanoma and Friend erythroleukemia, and the human K562 erythroleukemia, as doxorubicin (DXR)-sensitive and -resistant (multidrug resistant) variants. These effects were marked in B16 melanoma and rather slight in K562 erythroleukemia, without any difference between the DXR-sensitive and -resistant lines. The chemosensitive variant of Friend erythroleukemia …
Influence of Mitoxantrone on the Syntheses of Dna and Proteins of Mouse Tissues
In view of the structural similarity of mitoxantrone to anthracyclines and its ability to intercalate into DNA, we studied its influence on the synthetic processes of DNA and proteins in CD-1 mice tissues. By studying at the DNA level the impairment of 2H-thymidine incorporation and its return to normal, it was found that bone marrow and spleen showed similar behavior, i.e., a rapid return to normal, which occurred before bone marrow cell number and spleen weight returned to basal values. At the cardiac level, the incorporation values of precursors into DNA, reduced by treatment with mitoxantrone, came back very slowly to the control ones. Hepatic DNA showed a lower sensitivity to mitoxant…
Antioxidant defenses in a B16 melanoma line resistant to doxorubicin: an in vivo study.
A B16 melanoma line was repeatedly transplanted subcutaneously in C57BL/6 mice. On day 4 after every transplant, the animals were treated with doxorubicin (DXR), 10 mg/kg i.p. The aim of the work was to develop an in-vivo model of resistance to the antiblastic in order to analyze some possible mechanistic aspects of the process in the course of time. After 16 transplants and treatments the melanoma completely lost its sensitivity to the antiproliferative effects of maximal tolerated doses of DXR and showed over-expression of P-glycoprotein. Compared to the parental line, the in vitro resistance index was 4.6. After 27 transplants and treatments the melanoma did not increase its in vitro res…
Isolated myocardiocytes and DNA synthesis: a possible experimental model to predict the in vivo cardiotoxicity
Lysosomal alterations in heart and liver of mice treated with doxorubicin.
This study was carried out to evaluate the influence of long-term treatment with doxorubicin (DXR) (4mg/kg IV for 5 weeks) on heart and liver lysosomes of mice. We evaluated the variations in both total and "sedimentable" enzyme activity of cathepsin D, which is the major endopeptidase of myocites and probably involved in physiologic and pathologic degradation of actomyosin and mitochondria, and that of acid phosphatase, which is more prominent in interstitial cells. Our results show that marked changes occur in both total and sedimentable enzyme activity of cathepsin D in the heart of treated animals and to a lesser extent in the liver. In contrast, no modification of either total or sedim…
Combination chemotherapy with cyclophosphamide, doxorubicin and vincristine in the treatment of stage III-IV small-cell lung cancer.
SummaryTwenty patients with histologically confirmed small-cell lung cancer were treated with cyclophosphamide 1000 mg/m2 i.v. on day 1, vincristine 1.4 mg/m2 i.v. day 1, and adriamycin 50 mg/m2 i.v. on day 1. This protocol was repeated every 21 days. Out of 17 evaluable patients 2 obtained a complete response (12%) with a mean duration of 11 months, 4 patients achieved a partial response with a mean duration of 6.3 + months, and 1 had a minimal response of 7.2 months. Two patients had a stabilization which lasted a mean of 4 + months, while 8 patients progressed. Although the mean survival was higher in responders than in non-responders, the difference in survival time was not statisticall…
Difference in ki67 and thymidylate synthase expression in primary tumour compared with metastastic nodes in breast cancer patients. european society for the study of purine and pyrimidine metabolism in man
LOW CELL PROLIFERATION AND LOW THYMIDYLATE SYNTHASE LEVELS IN THE HIGLY AGGRESSIVE SIGNET RING CELL VARIANT HISTOTYPE OF COLORECTAL CARCINOMA
High-dose folinic acid and 5-fluorouracil plus cisplatin on a weekly schedule in the treatment of advanced cancer of the head and neck
A group of 60 patients with advanced head/neck cancer were treated with high-dose folinic acid (500 mg/m-2/week-1) plus 5-fluorouracil (400 mg/m-2/week-1 on day 1, and cisplatin (20 mg/m-2/week-1) 24 h after folinic acid infusion was completed. Out of 55 evaluable patients, 10 patients (18%) experienced a complete response with a mean duration of 11.4+ months, 25 patients had a partial response (45%) of 6.7+ months, 6 patients (11%) showed a stabilization of 4.8+ months, and 14 (25%) progressed. The overall response rate was 63.6% (95% confidence limits 56.5%-69.5%). Patients pretreated with radiotherapy had a 67% overall response rate, while those pretreated with chemotherapy showed a 54% …
Effect of human granulocyte colony stimulating factor (G-CSF) and reduced glutathione (GSH) on drug-induced leukopenia in golden Syrian hamsters.
Hydroxyurea modulates 5-fluorouracil antineoplastic activity in advanced head and neck carcinoma pretreated with chemotherapy
After informed consent 21 patients with advanced head and neck cancer resistant to folinic acid/5-fluorouracil (FA/5FU + cisplatin) were treated with weekly FA/5FU plus low dose hydroxyurea (HU) to evaluate if HU could further modulate 5FU antineoplastic activity. Five patients achieved a partial response (23.8%) which was short-lived (mean duration 6.5 months). Three patients (14%) had stable disease and 13 (62%) progressed. Among responders, four patients had epidermoidal carcinoma and one had clear cell carcinoma. Treatment was well tolerated and 5FU-related toxicity was not apparently worsened by the addition of HU. The most frequent toxicities were nausea/vomiting (81%), diarrhea (52%)…
Matrix metalloproteinase-1 is differentially expressed in signet ring cell, and intestinal colorectal carcinomas histotypes
14564 Background: Signet ring cell colorectal carcinoma ( SRCC) pure is an infrequent and highly malignant variant of colorectal cancer, while this histological component is present in 30% of all colorectal carcinomas. In our previous studies we compared the E- Cadherin, β- Catenin, Fibronectin, Ki 67 and Thymidylate Synthase (TS) expression of SRCC, the intestinal type of colorectal carcinoma (ICRC) to try to explain the pathogenesis, the aggressiveness and the low 5 Fluorouracil (5FU) responsiveness of these tumours. We found that all SRCCs had very low levels of all markers and were in the post- mitotic phase of the cell cycle. To understand their high metastatic capability we assessed …
Experimental techniques for testing the sensitivity of bladder tumours to antineoplastic drugs
A number of laboratory tests can be employed to examine the sensitivity of human bladder tumour cells to various chemotherapeutic agents.-Their principles and methods, and some preliminary results, are described with special reference to certain in vitro and in vivo cytotoxicity tests and to heterotransplantation in the hamster. Satisfactory agreement has sometimes been observed between experimental results and clinical responses, but our experience is still very limited.-The employment of several such tests would probably lead to a greater degree of reliability in the laboratory assessment of the sensitivity of bladder tumours to cytotoxic drugs.
Difference in Ki67 and thymidylate synthase expression in primary tumour compared with metastatic nodes in breast cancer patients.
Breast cancer is a heterogeneous disease, so therapeutic predictive biological markers need to be identified. To date an accurate evaluation of predictive markers is mainly done at the primary site; however, the main goal of adjuvant therapy for breast cancer is the control of micrometastases. The aim of this study is to assess as therapeutic and/or prognostic marker, the proliferation status of primary tumors and involved nodes as measured by Ki67 and thymidylate synthase (TS) expression, in 30 breast cancer node positive patients. TS is the main target of 5-fluorouracil (5-FU) activity, and its overexpression is one of the mechanisms of 5-FU drug resistance; however, in some studies its a…
Relationship between the thymidiylate synthase, P53 levels and the treatment by CMF drug combination versus taxanes in the locally advanced carcinoma of the breast
Effects of Tumor Necrosis Factor-Alpha on Growth and Doxorubicin Sensitivity of Multidrug Resistant Tumor Cell Lines
Biological agents might offer various therapeutic opportunities in the treatment of cancer, including a direct and/or host- mediated antiproliferative effect as well as the possibility to favourably modulate tumor sensitivity to antineoplastic drugs (Alexander et al., 1987; Kikuchi et al., 1992; Wadler and Schwartz, 1990). However, information on their activity on chemoresistant tumors is still scanty (Billi et al., 1991; Bonavida et al., 1989; D’Alessandro, 1993; Fruehauf et al., 1991; Liddill et al., 1988; Mihich and Ehrke, 1991). Here we have focused on tumor necrosis-alpha (TNF-α) and studied its in vitro effects on the growth of two tumor cell lines, the mouse B16 melanoma and Friend e…
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…
Clinical relevance of thymidylate syntetase expression in the signet ring cell histotype component of colorectal carcinoma
Thymidylate Synthase (TS) is the key enzyme for DNA synthesis pathways and is inhibited by 5-fluorouracil (5FU). The aim of this work was to study TS expression and the proliferation rate in the different histological types of colorectal carcinoma (CRC). 50 patients with CRC were included in this study and evaluated immunohistochemically using the monoclonal antibodies, TS106 and Ki67. 20 tumours were of the intestinal type, 15 cases were signet ring cell carcinoma (SRCCs) and 15 cases were "mixed-type", with at least two different histological components. Intestinal and mucinous histotypes were positive for TS and Ki67, while "signet ring cell" samples were negative or showed only weak and…
In vivo stimulation of murine haematopoiesis by the antineoplastic agent bryostatin-1
The role of histamine in doxorubicin and teniposide-induced cardiotoxicity in dog and mouse.
In previous studies we reported that teniposide (VM26) induced acute cardiac effects in dogs seem to be related to a release of histamine and that a prior treatment with chlorpheniramine, an H, histamine blocker, prevents the onset of this phenomenon. Since histamine and other vasoactive substances also seem to be involved in doxorubicin (DXR)-induced acute cardiac effects, experiments were undertaken in the aim to prevent, as in the case of VM26, the onset of this phenomenon by administering chlorpheniramine. Since DXR-induced chronic cardiomyopathy also seems to be related to the same mechanisms involved in the onset of acute cardiac effects induced by this drug, additional studies were …
Relationdhip between the thymidylate synthase, P53 levels and the treatment by CMF drug combination versus taxanes in the locally advanced carcinoma of breast
INFLUENCE OF α-6-DEOXY-5-OXYTETRACYCLINE ON SOME PHARMA-COLOGICAL CHARACTERISTICS OF DAUNOMYCIN
(1) Treatment with doxycyline substantially reduces the acute toxicity of daunomycin to the mouse. Treatment with doxycycline alters the distribution of daunomycin amongst the body tissues of the mouse. The ability of the isolated kidney to bind the daunomycin is enhanced by pretreatment with doxycycline. This observation is in agreement with the phenomenon noted in vivo with the same organ. (2) The antineoplastic activity of daunomycin, tested in vivo in mice bearing Sarcoma 180 is not modified by treatment with doxycyctine, nor does doxycycline modify the inhibition of DNA synthesis in isolated Sarcoma 180 cells by daunomycin. (3) The experiments carried out on isolated cell, namely: (a) …
The effectiveness of combination chemotherapy with cisplatinum and etoposide in the treatment of advanced non-small cell lung cancer.
Twenty-one patients with histologically proven advanced or disseminated non-small cell lung cancer were treated with cisplatinum 80 mg/m2 i.v. day 1 and etoposide (VP16) 80 mg/m2 i.v. day 1- greater than 3.15 patients were evaluable for response. One patient (6.6%) achieved a complete response, 4 (26.7%) a partial response and 6 (40.0%) a stabilization of disease. Four patients (26.7%) progressed. An improvement in performance status was obtained in more than 50% of cases. Responders had a mean survival of 345 + days, while non-responders 191.7 days. The treatment was generally well tolerated. In our opinion this combination regimen offers good palliation for patients affected by advanced a…
Vinblastine and interferon-alpha-2a regimen in the treatment of metastatic renal cell carcinoma.
Thirteen patients with histologically proven advanced and/or metastatic renal cell carcinoma (RCC) were treated with vinblastine (Velbe, Eli Lilly, Sesto Fiorentino, Italy) and interferon-alpha-2a (Roferon-A, Roche, Milan). Eleven out of 13 patients were evaluable. Eighteen percent of patients had partial response, 46 % stable disease (SD), and 36 % progressive disease (PD). The mean survival of responders was 228+ days, whereas the patients showing SD and PD had a mean survival of 154+ and 107+ days respectively. Toxicity, including influenza-like syndrome, fever, neurological and gastrointestinal side effects, was generally mild. However, medication with paracetamol was required in 82 % …
A Phase I–II Study on the Toxicity and Therapeutic Efficacy of 5-Fluorouracil in Combination with Leucovorin and Cisplatinum in Patients with Advanced Colorectal Carcinoma
5-Fluorouracil (5-FU) has been the treatment of choice for colorectal carcinoma with an overall response rate of about 20%. Recent studies have shown that folate (LV) can increase 5-FU therapeutic efficacy, achieving about a 40% response rate without a clear impact on survival. Cisplatinum (CDDP) is usually inactive in colorectal carcinoma, but the association with 5-FU results in a synergistic antineoplastic effect. A phase I-II study was done to assess the maximally tolerated dose (MTD) of CDDP in association with 5-FU + LV. The MTD for CDDP was 20 mg/m2/wk in association with 5-FU 400-500 mg/m2/wk and LV 500 mg/m2/wk. WHO criteria were used for evaluation of both toxicity and response. I…
Effect of Buthionine Sulfoximine on the Sensitivity to Doxorubicin of Parent and MDR Tumor Cell Lines
We have studied the interaction of glutathione-depleting concentrations of buthionine sulfoximine (BSO) with the anti-proliferative activity of doxorubicin (DXR) in three tumor lines, the mouse B16 melanoma. Friend erythroleukemia and the human K562 leukemia, both as DXR-sensitive and-resistant (with typical multidrug resistance) variants. BSO significantly enhanced the DXR effects in the wild-type Friend and K562 leukemias, and especially in the drug-resistant subline of Friend leukemia. BSO did not modify DXR accumulation and retention in the latter clone. Moreover, neither BSO nor verapamil used alone completely reversed the resistance to DXR of this cell line; their combination was more…
Dissimilar effects of doxorubicin and isoproterenol on morphology, H2O2 content and catalase activity in mouse heart
A Phase I Study of Cisplatinum plus 5-Fluorouracil in Modulation with Citrovorum Factor in Metastatic Colorectal Carcinoma
A phase I study of 5-fluorouracil 600 mg/m2/week and folinic acid 500 mg/m2/week on day 1 and cisplatin administered weekly on day 2 was carried out on 30 patients with metastatic colorectal carcinoma of which 20 patients were pretreated with 5-fluorouracil. The first group of patients received cisplatin at the dose of 5 mg/m2/week. Cisplatin was then escalated to 10, 15, 20, 25, 30, and 35 mg/m2/week for subsequent groups of patients. Gastrointestinal side-effects were the dose-limiting toxicity. A therapy related death was seen at the dose of 35 mg/m2/week of cisplatin. The maximally tolerated dose of cisplatin in combination with 5-fluorouracil and citrovorum factor is 20 mg/m2/week. The…
Phase II study of mitomycin C, etoposide and vindesine in metastatic stage IV non-small-cell lung cancer.
A total of 72 patients with metastatic stage IV non-small-cell lung cancer (NSCLC) were treated with combination chemotherapy comprising the MEV regimen (mitomycin C, 8 mg/m2 given i. v. on day 1; etoposide, 100 mg/m2 given i.v. on days 1–3; and vindesine, 3 mg/m2 given i.v. on day 1; treatment repeated every 3 weeks). In 64 evaluable patients, the objective response rate was 37% (complete responses, 4.7%; partial responses, 32.3%). The median survival was 7.6 months for all patients. The treatment was very well tolerated. MEV proved to be an active and non-toxic regimen for the treatment of metastatic NSCLC.
DIFFERENT EXPRESSION OF E-CADERINE, BETA CATENIN AND FIBRONECTIN IN SIGNET RING CELL AND INTESTINAL CARCINOMA.
Cis-diamminodichloroplatinum plus a 5-day continuous infusion of 5-fluorouracil in the treatment of locally recurrent and metastatic head and neck cancer patients.
A group of 23 consecutive patients with biopsy-proven advanced or metastatic head and neck cancer were treated with cisplatinum, 100 mg/m2 i.v., on day 1 plus 5-fluorouracil, 1000 mg/m2, in continuous infusion for 5 days. Most patients (87%) had recurrent or metastatic cancer and were previously treated (78%). Out of 21 evaluable patients we obtained a 42% overall response rate (complete + partial responses) with a mean duration of more than 8 months and a 14% minimal response rate. A stabilization of disease was achieved in 28% of cases, while 14% of patients progressed. This response rate, as well as the duration of response, seems to be similar to those obtained in other series comprisin…
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.
Oral tegafur in the treatment of gastrointestinal tract cancers: a phase II study.
Fifty patients affected by histologically confirmed gastrointestinal tract cancer (GTC) were treated with oral tegafur (TG) 1,000 mg m-2 p.o. on days 1-14 repeated after a 14 day interval. Out of 42 evaluable patients seven patients had a partial response (PR. 17%) with a median duration of 20.5 weeks, three had a minimal response (7%) with a median duration of 23.7 weeks, nine showed a stabilisation which lasted a median of 31.3 weeks, and 23 progressed (55%). No response was obtained in patients affected by carcinoma of the pancreas and the hepatobiliary system. All PRs were achieved in patients with metastatic disease to the liver. No response was seen in patients with bone, lung or noda…
Cardiac lysosomes in doxorubicin cardiotoxicity: An ultrastructural study
Influence of Pharmacokinetic Variations on the Pharmacological Properties of Adriamycin
Whenever it appears impossible to modify the chemical structure of drugs with a high and established therapeutic activity but a low chemotherapeutic index, pharmacological research has to find other ways of improving the chemotherapeutic index. This problem is particularly important in the case of antitumor drugs, thus justifying research into the most suitable choice of dosage and routes of administration, as well as into the pharmacological associations which enable tumor cells to be hit at various stages of the reproductive cycle. Alternatively, the therapeutic index could be improved by the use of antagonistic compounds (like, for example, methotrexate and folinic acid) which act upon t…
The significance of the Thymidylate Synthase expression in the Signet Ring Cell component of colorectal carcinoma
Cisplatinum in combination with 5-fluorouracil and citrovorum factor in the treatment of advanced colorectal carcinoma.
A phase II trial of citrovorum factor, 500 mg/m2/week, plus 5-fluorouracil, 400 mg/m2/week on day 1, and cisplatin, 20 mg/m2/week on day 2, was carried out in a group of 40 patients with metastatic colorectal carcinoma. A partial response with a mean duration of 8.4+ months was achieved in 24% of patients, a minimal response with a mean duration of 5.4 months was obtained in 6% of patients, and a stabilization of 6.2 months was achieved in 41%. Ten patients (29%) progressed. A 38% partial response rate was seen in patients with advanced rectal carcinoma, whereas no response was obtained in patients with colon cancer. Interestingly, 5 partial responses were seen in 12 patients pretreated wit…
LOW CELL PROLIFERATION AND LOW THYMIDYLATE SYNTHASE LEVELS IN THE HIGHLY AGGRESSIVE SIGNET RING CELL VARIANT HISTOTYPE OF COLORECTAL CARCINOMA
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…
DIFFERENT EXPRESSION OF E-CADHERINE, BETA-CATENIN, AND FIBRONECTIN IN SIGNET RING CELL AND INTESTINAL COLORECTAL CARCINOMA.
5-Fluorouracil and recombinant alpha interferon-2a in the treatment of advanced colorectal carcinoma: a dose optimization study
A dose optimization study was carried out with the aim of identifying the maximally tolerated dose of recombinant alpha interferon-2a (raIFN-2a) in combination with 5-fluorouracil (5FU). 5FU was given at the dose of 750 mg/m2 over a 4-hour infusion on day 1- - greater than 5 followed by 750 mg/m2 weekly i.v. bolus. Recombinant aIFN-2a was started at 3 x 10(6) IU subcutaneously three times/week. 12 patients with advanced colorectal carcinoma were included in the study. 10 patients had previously received chemotherapy for advanced disease. Severe fatigue, most likely attributable to rIFN, was the dose-limiting toxicity. The dosage of raIFN-2a could not be further escalated above 12 x 10(6) IU…
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…
Chemotherapy in head and neck cancer (I): Management of recurrent or metastatic disease
SummaryThis paper is an up-dated review of the role of systemic chemotherapy in the management of recurrent and/or metastatic head and neck carcinoma.