Phase II trial of capecitabine and weekly docetaxel in metastatic renal cell carcinoma.

OBJECTIVES: To evaluate the toxicity and efficacy of capecitabine and weekly docetaxel in a phase II clinical trial. METHODS: Eligibility included metastatic renal cancer with a maximum of 2 prior regimens, performance status of 0-2, and adequate renal, hepatic, and bone marrow function. Docetaxel was administered intravenously at a dose of 36 mg/m(2) weekly on days 1, 8, and 15 of a 28- day cycle and capecitabine was administered orally at a dose of 1800 mg/m(2) from days 5-18. Toxicity was assessed on days 1, 8, and 15 of each cycle, and response was evaluated every 2 cycles. RESULTS: Twenty-five patients, 19 white and 6 African American, were enrolled on this phase II trial. The median age was 60 years (range: 39-75 years). Eighteen patients had clear cell histology, 7 had papillary, sarcomatoid, or chromophobe histology. Thirteen had liver/bone metastases and 13 had >or=2 of the Memorial Sloan-Kettering Cancer Center prognostic risk factors. Twelve patients received prior immunotherapy. A total of 93 cycles were administered; median of 3 cycles and range from 0-10 cycles. The therapy was well tolerated. No treatment-related mortality was observed and 2 treatment-related hospitalizations for nausea, diarrhea, and dehydration occurred. Ten patients had stable disease. The median time to progression was 1.7 months and median survival was 11.1 months. CONCLUSIONS: The combination of capecitabine and docetaxel was well tolerated in metastatic renal cancer. Clinical activity was predominantly noted in non-clear cell histology in which chemotherapy would be worthy of future investigation.

Transcriptional profiling of degraded RNA in cryopreserved and fixed tissue samples obtained at autopsy.

BACKGROUND: Traditional multiplexed gene expression methods require well preserved, intact RNA. Such specimens are difficult to acquire in clinical practice where formalin fixation is the standard procedure for processing tissue. Even when special handling methods are used to obtain frozen tissue, there may be RNA degradation; for example autopsy samples where degradation occurs both pre-mortem and during the interval between death and cryopreservation. Although specimens with partially degraded RNA can be analyzed by qRT-PCR, these analyses can only be done individually or at low levels of multiplexing and are laborious and expensive to run for large numbers of RNA targets. METHODS: We evaluated the ability of the cDNA-mediated Annealing, Selection, extension, and Ligation (DASL) assay to provide highly multiplexed analyses of cryopreserved and formalin fixed, paraffin embedded (FFPE) tissues obtained at autopsy. Each assay provides data on 1536 targets, and can be performed on specimens with RNA fragments as small as 60 bp. RESULTS: The DASL performed accurately and consistently with cryopreserved RNA obtained at autopsy as well as with RNA extracted from formalin-fixed paraffin embedded tissue that had a cryopreserved mirror image specimen with high quality RNA. In FFPE tissue where the cryopreserved mirror image specimen was of low quality the assay performed reproducibly on some but not all specimens. CONCLUSION: The DASL assay provides reproducible results from cryopreserved specimens and many FFPE specimens obtained at autopsy. Gene expression analyses of these specimens may be especially valuable for the study of non-cancer endpoints, where surgical specimens are rarely available.

Pleotropic effects of genistein on MCF-7 breast cancer cells.

Soy isoflavone, genistein has been shown to induce growth inhibition, cell cycle arrest and apoptosis in cultured cancer cell lines derived from head and neck, breast, lung, and prostate cancers and showed antitumor activity against tumors in multiple animal models. In the present study we show that genistein inhibits the growth of MCF-7 breast cancer cell line in a dose dependent manner. The genistein induced growth inhibition is accompanied by the reduction in the number of mitotic cells and overexpression of cyclin dependent kinase inhibitor p21WAF1 leading to cell cycle arrest. In addition, the telomeric area was significantly reduced in genistein treated MCF-7 cells. Analysis of multiple genes involving the apoptotic pathway reveals inhibition of Akt activity without affecting the steady state levels of Akt protein expression and the down regulation of proapoptotic gene BAD expression. From these results, we conclude that genistein-induced inhibition of cell division is partly mediated by decreased telomere length, reduced mitosis and inhibition of Akt activation, leading to induction of apoptosis.

Role of mitochondria in ciprofloxacin induced apoptosis in bladder cancer cells.

PURPOSE: In our earlier series we showed that ciprofloxacin inhibits bladder tumor cell growth with concomitant S/G2M cell cycle arrest and reported an increased Bax-to-Bcl-2 ratio in cells undergoing cell death. In the current series we elucidated the molecular mechanisms by which ciprofloxacin induces apoptotic processes. MATERIALS AND METHODS: Ciprofloxacin mediated mitochondrial depolarization was detected by flow cytometry in HTB9 cells. Mitochondrial permeability transition was measured by spectrophotometry in isolated mitochondria treated with ciprofloxacin in the presence and absence of cyclosporin. The consequential decrease in mitochondrial calcium, cytochrome c release and Bax translocation to mitochondria, which resulted in the activation of caspase 3 leading to apoptotic cell death, was measured by biochemical and confocal microscopy. RESULTS: Mitochondrial depolarization was observed during ciprofloxacin induced apoptotic processes. Cyclosporin A, a known inhibitor of the mitochondrial permeability transition pore, protected cells against decreased mitochondrial potential. Also, ciprofloxacin induced an alteration of mitochondrial calcium as early as 5 minutes and this disruption of intracellular calcium homeostasis was prevented by cyclosporin. Ciprofloxacin also had a direct effect on swelling of isolated mitochondria, which was absent in the presence of cyclosporin. Mitochondrial changes were accompanied by cytochrome c release and caspase 3 activation. Our findings also showed Bcl-2 dependent subcellular redistribution of Bax to the mitochondrial membrane in ciprofloxacin treated bladder tumor cells. CONCLUSIONS: The disruption of calcium homeostasis, mitochondrial swelling and redistribution of Bax to the mitochondrial membrane are key events in the initiation of apoptotic processes in ciprofloxacin treated bladder cancer cells.

Molecular mechanism(s) of actinomycin-D induced sensitization of pancreatic cancer cells to CD95 mediated apoptosis.

The death receptor CD95 transduces apoptotic death signaling in many cell types. However, in pancreatic tumor cells CD95 mediated apoptotic machinery is blocked by unknown protein(s). We and others have recently demonstrated that actinomycin-D (ActD) treatment induces sensitization of pancreatic cancer cells as well as other cell types to CD95 mediated apoptosis. In addition, NF-kappaB/Akt system has been implicated in the processes of CD95 mediated apoptosis, however the precise mechanism by which ActD sensitizes pancreatic tumor cells to CD95 mediated apoptosis is still unknown. In the present study, we demonstrated that HPAC and PANC1 pancreatic cancer cells constitutively express high levels of NF-kappaB and phosphorylated form of Akt. ActD at a dose that is known to sensitize pancreatic cancer cells to CD95 mediated apoptosis abrogated the DNA binding activity of NF-kappaB but did not affect expression of phosphorylated Akt. Co-treatment of pancreatic cancer cells with ActD and agonist anti-CD95 antibodies showed no effect on the abrogation on the DNA binding activity of NF-kappaB, but decreased the expression of phosphorylated Akt. Moreover, treatment with PI3-kinase inhibitor LY294002 did not show any sensitization of pancreatic cancer cells to CD95 mediated apoptosis. Our data suggest that ActD sensitizes pancreatic cancer cells to CD95 mediated apoptosis through the abrogation of DNA binding activity of NF-kappaB, rather than PI3-kinase/Akt system. Over-expression of phosphorylated Akt in pancreatic cancer cells is controlled by effective apoptotic signaling from CD95 receptors, but do not protect tumor cells from CD95 induced apoptosis. Thus, our results indicate that modulation of NF-kappaB activity rather then Akt may provide a useful tool to sensitize pancreatic cancer cells to CD95 mediated apoptosis.