Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0023418 (leukemia)
 93,477 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Flavopiridol (NSC 649890, L86-8275), a potent inhibitor of cyclin-dependent kinase 1/p34cdc2 phosphorylation and kinase activity, is currently undergoing Phase I clinical testing as a potential antineoplastic agent. Previous studies have suggested that flavopiridol is cytostatic but not cytotoxic when applied to exponentially growing cells. In the present study, various human tumor cell lines were assayed for trypan blue exclusion and ability to form colonies after exposure to flavopiridol under a variety of growth conditions. When log phase A549 non-small cell lung cancer cells were examined 72 h after the start of a 24-h flavopiridol exposure, as many as 90% of the cells accumulated trypan blue. A 24-h exposure to 250-300 nM resulted in trypan blue uptake in 50% of A549 cells at 72 h and a 50% reduction in colony formation. Similar results were observed in HCT8 ileocecal adenocarcinoma, T98G glioblastoma, MCF-7 breast adenocarcinoma, and HL-60 leukemia cells. With A549 cells, identical results were obtained in actively growing logarithmic phase cells and growth-arrested confluent cells. Treatment with the DNA synthesis inhibitor aphidicolin only minimally affected the cytotoxicity of flavopiridol. In contrast, the RNA synthesis inhibitor 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole or the protein synthesis inhibitor cycloheximide reduced the cytotoxicity of flavopiridol. These results suggest that: (a) flavopiridol is not only cytostatic, but also cytotoxic to a variety of human tumor cell lines; (b) flavopiridol is equally active against cycling and noncycling A549 cells; and (c) RNA and protein synthesis appear to play a role in flavopiridol-induced cytotoxicity.
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PMID:Flavopiridol: a cytotoxic flavone that induces cell death in noncycling A549 human lung carcinoma cells. 889 33

A quality of life (QOL) endpoint supplemented standard clinical endpoints of survival, tumor response, and toxicity in a double-blind study conducted by the Cancer and Leukemia Group B (CALGB) where 291 patients with advanced non-small cell lung cancer (NSCLC) were randomly assigned to receive cisplatin/vinblastine with either hydrazine sulfate (HS) or placebo. The difficulties associated with the analysis of the longitudinal QOL data, and the contributions that the QOL endpoint made to the understanding of treatment differences, will be the focus of this paper.
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PMID:A longitudinal study of quality of life in advanced non-small cell lung cancer: Cancer and Leukemia Group B (CALGB) 8931. 925 70

Non-small cell lung cancer (NSCLC) remains the leading cause of cancer deaths in the United States. The combination of more active agents like vinorelbine and paclitaxel (Taxol; Bristol-Myers Squibb Company, Princeton, NJ) with cisplatin has led to improved survival for patients with advanced metastatic disease. The ability to escalate the dose of cisplatin-based regimens is limited by nonhematologic toxicities and is especially difficult in the population of patients with advanced NSCLC. However, the development of new agents with significant activity against NSCLC as well as new strategies for high-dose therapy have made it possible to examine the potential of dose-intense therapy in this population. A phase I trial performed at the University of North Carolina was designed to evaluate paclitaxel 250 mg/m2 given over 24 hours plus escalating doses of carboplatin starting at an area under the concentration-time curve (AUC) dose of 8 supported by peripheral blood stem cells and filgrastim in the treatment of advanced NSCLC. The AUC dose of carboplatin was escalated in increments of 2. The maximum tolerated dose of carboplatin combined with paclitaxel 250 mg/m2 administered over 24 hours was defined at an AUC of 18. In this study, six of seven patients with advanced NSCLC had major responses. This regimen is currently being tested in patients with locally advanced NSCLC by the Cancer and Leukemia Group B: patients receive two cycles of induction therapy with paclitaxel 250 mg/m2 over 3 hours followed by carboplatin at an AUC of 18 supported by peripheral blood stem cells and filgrastim. Depending on response to induction therapy, patients then receive surgical resection, thoracic radiation therapy, or both. This phase II trial will examine clinical and pathologic responses and the toxicity of this high-dose regimen in patients with locally advanced NSCLC. Ultimately, phase III trials will be needed to establish the role of this approach in NSCLC.
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PMID:High-dose therapy with carboplatin and paclitaxel in non-small cell lung cancer. 933 Nov 21

Since 1984, the Cancer and Leukemia Group B (CALGB) has focused its clinical research in stage IV non-small cell lung cancer (NSCLC) on investigations of new agents and combinations. Currently, efforts are aimed at identifying non-cisplatin-based combinations with an increased therapeutic index. In stage III disease multimodality therapies have been pursued. Dillman et al. reported a study comparing standard radiotherapy versus induction chemotherapy followed by radiotherapy in patients with unresectable stage III NSCLC. The chemotherapy-treated patients were found to benefit with a 4-month increase in median survival time compared with patients receiving radiotherapy alone (13.8 vs. 9.7 months) and an increased 3-year survival rate of 23% versus 11%. This was the first randomized cooperative group study demonstrating a survival advantage resulting from the use of induction chemotherapy in locoregionally advanced NSCLC. In a subsequent study, the administration of additional "posterior" chemotherapy was not found to be feasible because of early disease progression and toxicity, while the administration of induction chemotherapy followed by concomitant chemoradiotherapy was feasible; therefore, the latter approach was studied further in a randomized phase III setting. This study compared a standard of two cycles of cisplatin and vinblastine followed by radiotherapy with an experimental arm of cisplatin and vinblastine followed by radiotherapy and concomitant carboplatin. Accrual to this study has been completed and results are expected in the near future. In resectable stage III disease, studies have focused on the optimal sequencing of multimodality therapy. A randomized study comparing standard regional therapy with radiotherapy and surgery versus a previously piloted approach combining chemotherapy, surgery, and radiotherapy was closed prematurely due to poor accrual. The next generation of studies in stage III NSCLC will focus on the integration of new chemotherapy agents into the treatment armamentarium for NSCLC. A randomized phase II study investigating paclitaxel, gemcitabine, and vinorelbine in combination with cisplatin in the induction setting and as concomitant chemoradiotherapy has recently been activated.
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PMID:Clinical studies in non-small cell lung cancer: the CALGB experience. 951 72

The nicotinamide analogue 6-aminonicotinamide (6AN) is presently undergoing evaluation as a potential modulator of the action of various antineoplastic treatments. Most previous studies of this agent have focused on a three-drug regimen of chemical modulators that includes 6AN. In the present study, the effect of single-agent 6AN on the efficacy of selected antineoplastic drugs was assessed in vitro. Colony-forming assays using human tumor cell lines demonstrated that pretreatment with 30-250 microM 6AN for 18 h resulted in increased sensitivity to the DNA cross-linking agent cisplatin, with 6-, 11-, and 17-fold decreases in the cisplatin dose that diminishes colony formation by 90% being observed in K562 leukemia cells, A549 non-small cell lung cancer cells, and T98G glioblastoma cells, respectively. Morphological examination revealed increased numbers of apoptotic cells after treatment with 6AN and cisplatin compared to cisplatin alone. 6AN also sensitized cells to melphalan and nitrogen mustard but not to chlorambucil, 4-hydroperoxycyclophosphamide, etoposide, or daunorubicin. In additional studies undertaken to elucidate the mechanism underlying the sensitization to cisplatin, atomic absorption spectroscopy revealed that 6AN had no effect on the rate of removal of platinum (Pt) adducts from DNA. Instead, 6AN treatment was accompanied by an increase in Pt-DNA adducts that paralleled the degree of sensitization. This effect was not attributable to 6AN-induced decreases in glutathione or NAD+, because other agents that depleted these detoxification cofactors (buthionine sulfoximine and 3-acetylpyridine, respectively) did not increase Pt-DNA adducts. On the contrary, 6AN treatment increased cellular accumulation of cisplatin. Further experiments revealed that 6AN was metabolized to 6-aminonicotinamide adenine dinucleotide (6ANAD+). Concurrent administration of nicotinamide and 6AN had minimal effect on cellular 6AN accumulation but abolished the formation of 6ANAD+, the increase in Pt-DNA adducts, and the sensitizing effect of 6AN in clonogenic assays. These observations identify 6AN as a potential modulator of cisplatin sensitivity and suggest that the 6AN metabolite 6ANAD+ exerts this effect by increasing cisplatin accumulation and subsequent formation of Pt-DNA adducts.
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PMID:6-Aminonicotinamide sensitizes human tumor cell lines to cisplatin. 951 60

Ifosfamide and vinorelbine have demonstrated single-agent activity against advanced non-small cell lung cancer. The dose-limiting toxicity of each agent is myelosuppression. Several trials have studied this combination to determine its toxicity and efficacy in non-small cell lung cancer. We conducted a dose-escalation study of vinorelbine in a novel (daily x 3) schedule with ifosfamide and granulocyte colony-stimulating factor support to define the dose-limiting toxicities and maximum tolerated dose of vinorelbine in this combination. Other investigators have studied this combination in the phase II setting. In our phase I study involving 42 patients, the recommended phase II dose was vinorelbine 30 mg/m2 with ifosfamide 1.6 g/m2, each given on 3 consecutive days, followed by granulocyte colony-stimulating factor. The overall response rate was 40%, with a median survival of 50 weeks. Myelosuppression proved to be dose limiting for this regimen, without other major toxicities. Other groups have studied the ifosfamide/vinorelbine combination, and studies adding cisplatin to this regimen have been conducted as well. Given the tolerable toxicity and encouraging response rates and 1-year survival rate seen with this regimen, further investigation of the ifosfamide/vinorelbine regimen has continued in a phase II Cancer and Leukemia Group B trial. Further study of the potential application of the combination as induction therapy for stage III disease is warranted.
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PMID:A review of ifosfamide and vinorelbine in advanced non-small cell carcinoma of the lung. 953 5

Several studies have suggested that biochemical or molecular markers examined in non-small cell lung cancer carry prognostic or treatment response information. Non-small cell lung cancer patients whose tumors have neuroendocrine (NE) features may be more responsive to chemotherapy. In addition, increased expression of HER2 (c-erbB-2), a membrane-bound receptor with tyrosine kinase activity, has been associated with shortened survival. The Cancer and Leukemia Group B (CALGB) performed a study of patients with stage IIIA (N2 nodes positive) non-small cell lung cancer in which patients received initial chemotherapy followed by surgery, then post-operative therapy consisting of sequential chemotherapy and radiation therapy. Since all patients underwent mediastinoscopy, this provided an opportunity to compare pre- and post-chemotherapy tumor specimens to test the hypothesis that these proteins would predict treatment response. In particular, we hypothesized that the post-chemotherapy specimens would be enriched for NE marker negative cells because of the increased sensitivity of NE positive cells to chemotherapy. We performed immunohistochemical analysis for a panel of NE markers [neuron-specific enolase (NSE), Leu-7, chromogranin A (ChrA), synaptophysin (Syn)], HER2 and CEA to determine if there was an effect of therapy on the percentage of cells expressing these markers. Secondary endpoints were a correlation with chemotherapy response and survival. Slides were scored for intensity (0-4) and percentage of cells positive (0-4). Of 61 eligible patients, there were 38 with both pre- and post-chemotherapy specimens. When both intensity of staining and percentage of positive cells were considered, post-chemotherapy specimens had a higher percentage of positive NE markers compared with pre-chemotherapy. In addition, there was no correlation between NE marker, HER2 or CEA expression (prior to or post treatment) and response to chemotherapy or survival. These data do not support the hypothesis that NE positive tumor cells are preferentially killed by chemotherapy in patients with stage IIIA non-small cell lung cancer.
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PMID:Analysis of neuroendocrine markers, HER2 and CEA before and after chemotherapy in patients with stage IIIA non-small cell lung cancer: a Cancer and Leukemia Group B study. 985 98

Several randomized trials have compared single-agent chemotherapy with combination chemotherapy in advanced non-small cell lung cancer. In general, response rates were higher with combination regimens, but their impact on survival is unclear. We conducted a meta-analysis of 25 trials involving a total of 5,156 patients with advanced non-small cell lung cancer randomized to a single-agent arm versus a combination arm. The results showed that combination chemotherapy produced a nearly twofold increase in response rate and a modestly improved 1-year survival rate compared with single-agent chemotherapy. However, toxicity was significantly increased, with a 3.6-fold increase in treatment-related mortality. In a subset analysis of trials using either a platinum analog or vinorelbine as single agents and as a component of the combination regimen, the difference was no longer statistically significant, suggesting that more active single agents provide similar survival with less toxicity than combination regimens. Based on these results, the Cancer and Leukemia Group B initiated a large randomized trial comparing paclitaxel with paclitaxel + carboplatin in stage IIIB-IV non-small cell lung cancer patients. The trial will be able to detect a 30% difference in survival. An extensive quality of life analysis and a resource utilization comparison will allow estimation of the incremental cost per quality of life-year gained. This trial will be the first in the United States to prospectively collect and analyze such data in a multidisciplinary approach.
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PMID:Single-agent versus combination chemotherapy in advanced non-small cell lung cancer: a meta-analysis and the Cancer and Leukemia Group B randomized trial. 1056 12

In order to explore non-cisplatin containing regimens for advanced non-small cell lung cancer, Cancer and Leukemia Group B conducted a randomized Phase-II study of two novel combinations, paclitaxel/ifosfamide and vinorelbine/ifosfamide. Both regimens were active with a 38% response rate (95% CI: 24%, 53%) and 31% (95% CI: 18%, 47%), respectively. Median survivals were 8.5 and 7.4 months. Toxicity, mostly neutropenia, was acceptable. These two combinations establish a 'proof of principle' that non-cisplatin containing regimens also have activity in this setting.
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PMID:Paclitaxel/ifosfamide or navelbine/ifosfamide chemotherapy for advanced non-small cell lung cancer: CALGB 9532. 1070 11

This paper presents a reanalysis of a randomized clinical trial conducted by the Cancer and Leukemia Group B (CALGB, Bethesda, MD, USA). This trial found a significant benefit of combination chemotherapy followed by irradiation (CTRT) in comparison to radiotherapy alone (RT) for the treatment of nonsmall cell lung cancer. The validity of the results obtained and the decision to terminate taken by the CALGB, were assessed using sequential methods. The reliability and efficiency of sequential methods were also assessed for this study. Two sequential designs were used: the triangular and the restricted procedure. Initial analyses were conducted with the data from patients actually recruited, adjusting for important prognostic variables at any interim analysis. As a confirmatory technique, a continuation of the trial was simulated, sampling extra patients under the assumption of no treatment difference, preserving the effect of the prognostic variables. Using the results from the 155 patients recruited by the CALGB (88 deaths at termination and 136 after follow-up), the sample path stayed within the continuation region of both sequential designs considered. An underpowered sequential analysis showed significant superiority of CTRT over RT (95% confidence interval (95% CI) 0.50-0.96, p=0.03 for the triangular; 95% CI 0.37-0.88, p=0.01 for the restricted procedure). Conventional analysis of the follow-up data also showed significant superiority of CTRT. The trial extended with simulated data ended at 60 months with 251 patients (178 deaths), showing significant superiority of CTRT under both designs (95% CI for hazard ratio 0.55-0.97). The two sequential procedures would have led to the same conclusion as that reached by the Cancer and Leukemia Group B, still achieving considerable savings in patients recruited and time over the conventional design. The data simulated under the rather conservative null hypothesis did not reverse the positive result claimed by the Cancer and Leukemia Group B.
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PMID:Sequential re-analysis of a phase-III clinical trial in non-small cell lung cancer. 1085 42


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