Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The aim of this study was to explore, in a murine tumor, if the effectiveness of radiation, in doses and schedules commonly used in clinical practice is potentiated by the combined use of the recently developed drug gemcitabine. Gemcitabine (30-360 mg/kg b.w.) was administered i.p. in female C3D2F1 mice bearing a mammary adenocarcinoma alone or combined with X-rays. Firstly, gemcitabine (single administration) was administered alone or at 20 min, 4 h, and 24 h before X-ray treatments. The significant effect observed only at 24 h time interval, depended on the X-ray dose and not on the gemcitabine dose. Secondly, 4 gemcitabine administrations every 3 days were used in fractionated combined schedules (overall treatment time of 10 days). We studied the relationship among different doses of gemcitabine, alone or combined with 10 daily X-ray treatments (2 Gy/fraction). We observed an interactive effect of gemcitabine up to its threshold dose of 60 mg/kg/fraction. Furthermore, 10 X-ray daily treatments and 4 X-ray treatments every 3 days (total doses 20-40 Gy) were performed with gemcitabine 60 mg/kg/fraction to study the effect of different doses and schedules of X-rays. Tumor growth delays increase with higher X-ray doses, and this occurs more with 4 X-ray treatments than with 10 X-ray treatments. Our results re-affirm the uselessness of high gemcitabine doses, and indicate the effectiveness of combined gemcitabine-radiation fractionated protocols.
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PMID:Combined use of gemcitabine and radiation in mice. 1129 53

One of the main reasons for the increased acceptance of chemotherapy for both early and advanced non-small-cell lung cancer is the clinical availability of several new cytotoxic drugs. These less toxic, yet highly effective, new drugs not only benefit younger patients, but also offer new treatment opportunities for the elderly; advanced age alone should not preclude appropriate cytotoxic therapy. Vinorelbine (Navelbine) was the first new agent tested in randomized trials with elderly patients having advanced non-small-cell lung cancer. Results proved that vinorelbine does indeed have a survival advantage over best supportive care for these patients. Gemcitabine (Gemzar) is probably the most effective cytotoxic agent in the treatment of non-small-cell lung cancer today, showing high antitumor activity as a single agent and in combination. Moreover, it has a favorable toxicity profile. Since it can be effectively used for the palliation of tumor-related symptoms and can thus positively influence performance status, gemcitabine may be of great clinical importance in the treatment of elderly and unfit patients. Docetaxel (Taxotere) has recently become the first agent to be registered for second-line chemotherapy in non-small-cell lung cancer. This decision was based on survival advantages and clinical benefit data stemming from two randomized phase III studies. Nonetheless, chemotherapy for elderly patients continues to be a major unresolved oncologic problem. Clinical research with the new cytotoxic agents should be intensified to further define the most appropriate use for these drugs as single agents or in combination for the treatment of elderly patients.
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PMID:Treatment of elderly patients with non-small-cell lung cancer. 1130 49

Gemcitabine is a promising new agent that has been recently studied for palliation of advanced (stage IV) unresectable pancreatic cancer. We hypothesized that adjuvant gemcitabine would reduce recurrence and metastases following surgical resection of pancreatic cancer. To test this hypothesis, we evaluated gemcitabine on a green fluorescent protein (GFP) transductant of the human pancreatic cancer cell line BxPC-3 (BxPC-3-GFP) using surgical orthotopic implantation (SOI) in nude mice. GFP enabled high resolution fluorescent visualization of primary and metastatic growth. Five weeks after SOI, the mice were randomized into three groups: Group I received exploratory laparotomy only. Group II underwent surgical resection of the pancreatic tumor without further treatment. Group III underwent tumor resection followed by adjuvant treatment with gemcitabine, 100 mg/kg every three days for a total of four doses, starting two days after resection. The mice were sacrificed at thirteen weeks following implantation and the presence and location of recurrent tumor was recorded. Gemcitabine reduced the recurrence rate to 28.6% compared to 70.6% with resection only (P = 0.02) and reduced metastatic events 58% in the adjuvant group compared to resection only. This study, demonstrating that gemcitabine is effective as adjuvant chemotherapy post-pancreatectomy, suggests this new indication of the drug clinically.
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PMID:Antimetastatic efficacy of adjuvant gemcitabine in a pancreatic cancer orthotopic model. 1146 69

The aim of this phase II multicenter trial was to evaluate the activity of a novel combination of gemcitabine (GEM) and epirubicin (EPI) in advanced pancreatic cancer patients. Clinical benefit and response rate were the main efficacy end-points. From December 1997 to October 1999, 30 consecutive patients with measurable advanced pancreatic cancer were enrolled. Gemcitabine was administered intravenously in 30 min at a dose of 800 mg/m2 on days 1, 8, 15 followed by i.v. injection of epirubicin 25 mg/m(2); treatment was repeated every 28 days. With regard to clinical benefit response, 8/21 patients (38%) experienced significant palliation of tumor-related symptoms; the median symptom control time was 25 weeks. No complete responses were recorded while 6 patients achieved a partial remission, for an overall response rate of 20%; 10 patients (30%) had a stable disease and 14 (46%) had progressive disease. The median time to progression was 14 weeks. Median survival was 26 weeks, with 6 patients (20%) having long-term survival at 46 weeks. In general, chemotherapy was well tolerated; 9 patients (30%) suffered from WHO grade 3-4 haematological toxicity and 5 patients (16.6%) suffered from grade 3 non-haematological toxicity. In conclusion, the GEM plus EPI regimen represent a feasible approach for improvement of clinical benefit in advanced pancreatic cancer patients, but confirmatory investigations are required.
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PMID:Gemcitabine plus epirubicin in advanced pancreatic cancer: a phase II multicenter trial. 1149 26

Increased cyclooxygenase-2 (COX-2) expression in human pancreatic adenocarcinomas, as well as the growth-inhibitory effect of nonsteroidal anti-inflammatory drugs (NSAIDs) in vitro, suggests that NSAIDs may be an effective treatment for pancreatic cancer. Gemcitabine is currently the most effective chemotherapeutic drug available for patients with pancreatic cancer, but is only minimally effective against this aggressive disease. Clearly, other treatment options must be identified. To design successful therapeutic strategies involving compounds either alone or in combination with others, it is necessary to understand their mechanism of action. In the present study, we evaluated the effects of three NSAIDs (sulindac, indomethacin, and NS-398) or gemcitabine in two human pancreatic carcinoma cell lines, BxPC-3 (COX-2-positive) and PaCa-2 (COX-2-negative), previously shown to be growth-inhibited by these NSAIDs. Effects on cell cycle and apoptosis were investigated by flow cytometry or Western blotting. Treatment with NSAIDs or gemcitabine altered the cell cycle phase distribution as well as the expression of multiple cell cycle regulatory proteins in both cell lines, but did not induce substantial levels of apoptosis. Furthermore, we demonstrated that the combination of the NSAID sulindac or NS-398 with gemcitabine inhibited cell growth to a greater degree than either compound alone. These results indicate that the antiproliferative effects of NSAIDs and gemcitabine in pancreatic tumor cells are primarily due to inhibition of cell cycle progression rather than direct induction of apoptotic cell death, regardless of COX-2 expression. In addition, NSAIDs in combination with gemcitabine may hold promise in the clinic for the treatment of pancreatic cancer.
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PMID:Cell cycle effects of nonsteroidal anti-inflammatory drugs and enhanced growth inhibition in combination with gemcitabine in pancreatic carcinoma cells. 1150 93

The purpose of this ongoing study is to determine the response and safety of a combination of gemcitabine (Gemzar; Eli Lilly and Company, Indianapolis, IN) plus doxorubicin as neoadjuvant therapy for stage IIIB breast cancer. Thirty-nine chemotherapy-naive patients were enrolled in the study. The median age was 54 years (range, 32 to 74 years), and the median Karnofsky performance status was 100. Gemcitabine 1,200 mg/m(2) was given on days 1 and 8, and doxorubicin 60 mg/m(2) on day 1, followed by surgery or radiotherapy. Ninety-seven of 117 cycles (83%) were administered at full dose. An overall response rate of 95% was obtained, with a complete response in 18% (seven patients) and a partial response in 77% (30 patients). Twenty-eight patients (72%) underwent breast surgery after a maximum of three cycles of neoadjuvant therapy. World Health Organization grade 3/4 toxicities included leukopenia in nine cycles (8%), neutropenia in 16 cycles (14%), febrile neutropenia in 11 cycles (9%), and anemia in two cycles (2%). The most important nonhematologic toxicity was grade 2/4 mucositis in 16 cycles (14%), and/or grade 2/3 diarrhea in 10 cycles (9%). Neoadjuvant therapy with gemcitabine plus doxorubicin results in a high tumor response rate with moderate oral and hematologic toxicity. Semin Oncol 28 (suppl 10):57-61.
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PMID:A phase II study of neoadjuvant gemcitabine plus doxorubicin in stage IIIB breast cancer: a preliminary report. 1151 35

Pancreatic cancer is resistant to almost all classes of cytotoxic agents. Gemcitabine seems to be the current drug of choice. We have recently reported that inhibition of the phosphatidylinositide 3-kinase-protein kinase B (PKB/Akt) cell survival pathway by wortmannin enhances gemcitabine-induced apoptosis in cultured human pancreatic cancer cells (1). The present study investigated the effects of wortmannin on orthotopic human pancreatic cancer xenografts implanted in severe combined immunodeficient mice. Animals were given single i.v. bolus injections of 0.175, 0.35, or 0.7 mg/kg of wortmannin and killed at 0.5, 1, 2, or 4 h after treatment. Phosphorylated PKB/Akt levels in tumor tissues were measured by fluorescence image analysis. Wortmannin was found to inhibit PKB/Akt phosphorylation in a time- and dose-dependent manner, reaching a plateau at 4 h and at 0.7 mg/kg. The levels of phosphorylated PKB/Akt were maximally decreased by approximately 50% relative to the vehicle control. Subsequently, the extent of apoptosis in tumors treated with gemcitabine or wortmannin alone or in combination was determined using terminal deoxynucleotidyl transferase-mediated nick end labeling assay and computerized image analysis. Orthotopic tumors exposed to 80 mg/kg gemcitabine for 48 h and then 0.7 mg/kg wortmannin for 4 h showed a 5-fold increase (P = 0.002) in apoptosis compared with those treated with each agent alone and with the vehicle control. The combination treatment also significantly (P < 0.001) inhibited tumor growth. Taken together, our findings support the potential of phosphatidylinositide 3-kinase inhibitors as adjuncts to conventional chemotherapy in the treatment of pancreatic cancer.
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PMID:Wortmannin inhibits pkb/akt phosphorylation and promotes gemcitabine antitumor activity in orthotopic human pancreatic cancer xenografts in immunodeficient mice. 1159 24

Chemotherapeutic drugs that perturb nucleotide metabolism have the potential to produce substantial sensitization of tumor cells to radiation treatment. The clinical effectiveness of fluoropyrimidines as radiosensitizers has been proven in multiple randomized trials. The development of oral fluoropyrimidine formulations may allow protracted exposure without the need for indwelling intravenous lines and infusion pumps. These agents may also provide more selective radiosensitization and are likely to be widely incorporated into chemoradiotherapy regimens for patients with gastrointestinal malignancies. Gemcitabine has been well studied in the laboratory, with respect to mechanisms of radiosensitization and strategies that may increase the therapeutic index. Clinical trials based on these studies are now defining the role of this radiosensitizing nucleoside. Issues regarding the use oral fluoropyrimidines and gemcitabine need to be viewed in the context of both local and distant disease control, given the potential systemic activity of these agents.
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PMID:Recent advances in the use of radiosensitizing nucleosides. 1167 52

Pancreatic cancer has extremely poor prognosis. However no satisfactory effective chemotherapy for this cancer has been established. Gemcitabine hydrochloride, a novel anti-tumor agent, had shown the remarkable clinical efficacy for pancreatic cancer. In April 2001, the indication for pancreatic cancer of this agent has been approved in Japan and it is expected to be widely and increasingly introduced for clinical use. This review summarizes the study results of gemcitabine mono-therapy for pancreatic cancer and discusses other possibility of the treatment by Gemcitabine with the reported data about its combination therapy with other anti-cancer drug or radiation.
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PMID:[Results of gemcitabine hydrochloride in the treatment for pancreatic cancer]. 1168 Dec 59

The aim of the present phase II study was to assess the activity and safety of gemcitabine-cisplatin combination in advanced NSCLC, and to evaluate the impact of this regimen in terms of symptom benefit and quality of life (QOL). Eighty patients with pathologically confirmed advanced (stage IIIB and IV) NSCLC were enrolled into this study. Gemcitabine was administered on days 1, 8 and 15 at a dose of 1000 mg/m(2), and cisplatin was given on day 2 at a dose of 100 mg/m(2). The cycles were repeated every 4 weeks. The impact of treatment on QOL and on tumor-related symptoms was evaluated with the validated EORTC forms (QLQ-C30 and LC-13). The regimen was relatively well tolerated. Myelosuppresion was the principal toxicity. Grade 3/4 neutropenia, thrombocytopenia and anemia occurred in 58, 65 and 30% of patients respectively. In 143 cycles (35%) the administration of gemcitabine on day 15 was omitted due to myelosuppresion. Non-hematological toxicities were generally mild. Among the 76 patients available for response evaluation, there were 5 complete responses (7%) and 26 partial responses (34%); an overall response rate of 41%. The median duration of response was 8.0 months. The median survival for all 80 patients was 11.0 months and the actuarial 1-year survival probability 45%. During therapy global QOL improved in 22% of patients and particular functional domains increased in 19-37% of patients. Dyspnea was released in 36% of patients, fatigue in 45%, chest pain in 38%, shoulder pain in 27%, cough in 44%, and hemoptysis in 75%. The mean intensity scores of the last three symptoms decreased significantly with therapy. Our study confirmed relatively high efficacy of the gemcitabine-cisplatin combination in patients with advanced NSCLC. Of particular importance was that treatment with gemcitabine-cisplatin combination in a large proportion of patients was also associated with remarkable symptomatic release and with improvement of QOL. However, the high frequency of myelotoxicity-related gemcitabine omissions on day 15 of the cycle indicates that modification of the schedule should be considered in standard care.
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PMID:A phase II study of gemcitabine plus cisplatin in patients with advanced non-small cell lung cancer: clinical outcomes and quality of life. 1175 Jul 16


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