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1.  Abiraterone and Increased Survival in Metastatic Prostate Cancer 
The New England journal of medicine  2011;364(21):1995-2005.
Biosynthesis of extragonadal androgen may contribute to the progression of castration-resistant prostate cancer. We evaluated whether abiraterone acetate, an inhibitor of androgen biosynthesis, prolongs overall survival among patients with metastatic castration-resistant prostate cancer who have received chemotherapy.
We randomly assigned, in a 2:1 ratio, 1195 patients who had previously received docetaxel to receive 5 mg of prednisone twice daily with either 1000 mg of abiraterone acetate (797 patients) or placebo (398 patients). The primary end point was overall survival. The secondary end points included time to prostate-specific antigen (PSA) progression (elevation in the PSA level according to prespecified criteria), progression-free survival according to radiologic findings based on prespecified criteria, and the PSA response rate.
After a median follow-up of 12.8 months, overall survival was longer in the abiraterone acetate–prednisone group than in the placebo–prednisone group (14.8 months vs. 10.9 months; hazard ratio, 0.65; 95% confidence interval, 0.54 to 0.77; P<0.001). Data were unblinded at the interim analysis, since these results exceeded the preplanned criteria for study termination. All secondary end points, including time to PSA progression (10.2 vs. 6.6 months; P<0.001), progression-free survival (5.6 months vs. 3.6 months; P<0.001), and PSA response rate (29% vs. 6%, P<0.001), favored the treatment group. Mineralocorticoid-related adverse events, including fluid retention, hypertension, and hypokalemia, were more frequently reported in the abiraterone acetate–prednisone group than in the placebo–prednisone group.
The inhibition of androgen biosynthesis by abiraterone acetate prolonged overall survival among patients with metastatic castration-resistant prostate cancer who previously received chemotherapy. (Funded by Cougar Biotechnology; COU-AA-301 number, NCT00638690.)
PMCID: PMC3471149  PMID: 21612468
2.  TGFbeta induces apoptosis and EMT in primary mouse hepatocytes independently of p53, p21Cip1 or Rb status 
BMC Cancer  2008;8:191.
TGFβ has pleiotropic effects that range from regulation of proliferation and apoptosis to morphological changes and epithelial-mesenchymal transition (EMT). Some evidence suggests that these effects may be interconnected. We have recently reported that P53, P21Cip1 and pRB, three critical regulators of the G1/S transition are variably involved in TGFβ-induced cell cycle arrest in hepatocytes. As these proteins are also involved in the regulation of apoptosis in many circumstances, we investigated their contribution to other relevant TGFβ-induced effects, namely apoptosis and EMT, and examined how the various processes were interrelated.
Primary mouse hepatocytes deficient in p53, p21 and/or Rb, singly or in combination were treated with TGFβ for 24 to 96 hours. Apoptosis was quantified according to morphology and by immunostaining for cleaved-capsase 3. Epithelial and mesenchymal marker expression was studied using immunocytochemistry and real time PCR.
We found that TGFβ similarly induced morphological changes regardless of genotype and independently of proliferation index or sensitivity to inhibition of proliferation by TGFβ. Morphological changes were accompanied by decrease in E-cadherin and increased Snail expression but the mesenchymal markers (N-cadherin, SMAα and Vimentin) studied remained unchanged. TGFβ induced high levels of apoptosis in p53-/-, Rb-/-, p21cip1-/- and control hepatocytes although with slight differences in kinetics. This was unrelated to proliferation or changes in morphology and loss of cell-cell adhesion. However, hepatocytes deficient in both p53 and p21cip1were less sensitive to TGFβ-induced apoptosis.
Although p53, p21Cip1 and pRb are well known regulators of both proliferation and apoptosis in response to a multitude of stresses, we conclude that they are critical for TGFβ-driven inhibition of hepatocytes proliferation, but only slightly modulate TGFβ-induced apoptosis. This effect may depend on other parameters such as proliferation and the presence of other regulatory proteins as suggested by the consequences of p53, p21Cip1 double deficiency. Similarly, p53, p21Cip1 and pRB deficiency had no effect on the morphological changes and loss of cell adhesion which is thought to be critical for metastasis. This indicates that possible association of these genes with metastasis potential would be unlikely to involve TGFβ-induced EMT.
PMCID: PMC2467431  PMID: 18611248
3.  Chemotherapy for hormone-resistant prostate cancer: Where are we today? 
Significant progress has been achieved in chemotherapy for hormone-resistant prostate cancer (HRPC) in the last five years. Although the disease was long considered to be chemoresistant, docetaxel-based regimens in particular have been shown to both palliate symptoms and prolong survival in HRPC patients. Docetaxel is now considered the best available chemotherapy for prostate cancer progressing on first-line hormonal treatment. Other cytotoxics including mitoxantrone, anthracyclines, vinorelbin and vinblastine can alleviate symptoms and improve progression-free survival in HRPC without affecting overall survival. The survival benefit from chemotherapy seen in randomized studies has been small or nonexistent. Results of a recent trial suggest that the survival benefit may have been underestimated as a result of crossover from the less active to the active arm.
PMCID: PMC2721498  PMID: 19675765
Chemotherapy; docetaxel; estramustine; hormone-refractory prostate cancer; mitoxantrone

Results 1-3 (3)