[Show abstract][Hide abstract] ABSTRACT: Aberrant Nuclear Factor-κappaB (NF-κB) activation due to rapid IκBα turnover and high basal IκBα kinase (IKK) activity has been frequently observed in prostate cancer. Apigenin, a naturally occurring plant flavone, exhibits anti-proliferative, anti-inflammatory and anti-carcinogenic activities by inhibiting NF-κB pathway, through a mechanism not fully understood. We found that apigenin feeding in microgram doses (bioavailable in humans) inhibited prostate tumorigenesis in TRAMP mice by interfering with NF-κB signaling. Apigenin feeding to TRAMP mice (20 and 50 μg/mouse/day, 6 days/week for 20 weeks) exhibited significant decrease in tumor volumes of the prostate and completely abolished metastasis, which correlated with inhibition of NF-κB activation and binding to the DNA. Apigenin intake blocked phosphorylation and degradation of IκBα by inhibiting IKK activation, which in turn led to suppression of NF-κB activation. The expression of NF-κB-regulated gene products involved in proliferation (cyclin D1, and COX-2), anti-apoptosis (Bcl-2 and Bcl-xL), and angiogenesis (vascular endothelial growth factor) were also downregulated after apigenin feeding. These events correlated with the induction of apoptosis in tumor cells, as evident by increased cleaved caspase-3 labeling index in the dorsolateral prostate. Our results provide convincing evidence that apigenin inhibits IKK activation and restores the expression of IκBα, preventing it's phosphorylation in a fashion similar to that elicited by IKK and proteasomal inhibitors through suppression of NF-κB signaling pathway.
PLoS ONE 09/2015; 10(9):e0138710. DOI:10.1371/journal.pone.0138710 · 3.23 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: High-dose chemotherapy followed by autologous hematopoietic cell transplantation (HCT) improves outcomes in relapsed lymphoma, but the relative efficacy of different preparative regimens is not well defined. We included patients undergoing autologous HCT using BEAM (carmustine, 300 mg/m2, etoposide, cytarabine, and melphalan) or BEP (carmustine 600 mg/m2, etoposide, and cisplatin) between January 2004 and December 2013; 65 patients received BEP and 64 patients BEAM. Both cohorts were similar for advanced-stage disease, extranodal and bulky disease, and prior therapies. Median neutrophil and platelet engraftment was 10 and 20 days for both regimens, respectively. Febrile neutropenia, serum creatinine concentration increase, and electrolyte abnormalities were more frequent with BEP. Incidence of carmustine pneumonitis was not higher with BEP, likely the result of corticosteroid prophylaxis, although 2 cases of fatal pneumonitis were observed after BEP. One-year nonrelapse mortality was 6.8% after BEP and 0% after BEAM (P = .379). After a median follow-up of 39.4 months (range, 1 to 128), 4-year rates of overall survival (OS) after BEP and BEAM were 80.4% and 72.3%, respectively (P = .611). Diffuse large B cell lymphoma patients transplanted after early relapse post–rituximab-based first-line therapy presented 3-year rates of OS and progression-free survival (PFS) of 73.8% and 65%, respectively. There were no statistically significant differences in the OS and PFS of follicular lymphoma, mantle cell lymphoma, or Hodgkin lymphoma. BEP is a valid alternative to BEAM in autologous HCT. Although associated with more renal and electrolytic toxicities, BEP results in similar disease control and long-term survival as BEAM. Prospective studies are needed to confirm whether intensification of conditioning regimens for autologous HCT can improve disease control in high-risk relapsed lymphoma patients.
Biology of blood and marrow transplantation: journal of the American Society for Blood and Marrow Transplantation 06/2015; DOI:10.1016/j.bbmt.2015.06.007 · 3.40 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Background
Delayed chemotherapy is associated with inferior survival in stage III colon and stage II/III rectal cancer patients, but similar studies have not been performed in stage II colon cancer patients. We investigate the association between delayed and incomplete chemotherapy, and the association of delayed chemotherapy with survival in stage II colon cancer patients.
Patients and Methods
Patients (age ≥66) diagnosed as stage II colon cancer and received chemotherapy from 1992 to 2005 were identified from the linked SEER–Medicare database. The association between delayed and incomplete chemotherapy was assessed using unconditional and conditional logistic regressions. Survival outcomes were assessed using stratified Cox regression based on propensity score matched samples.
4,209 stage II colon cancer patients were included, of whom 73.0% had chemotherapy initiated timely (≤2 months after surgery), 14.7% had chemotherapy initiated with moderate delay (2–3 months), and 12.3% had delayed chemotherapy (≥3 months). Delayed chemotherapy was associated with not completing chemotherapy (adjusted odds ratio (OR): 1.33 (95% confidence interval: 1.11, 1.59) for moderately delayed group, adjusted OR: 2.60 (2.09, 3.24) for delayed group). Delayed chemotherapy was associated with worse survival outcomes (hazard ratio (HR): 1.75 (1.29, 2.37) for overall survival; HR: 4.23 (2.19, 8.20) for cancer-specific survival).
Although the benefit of chemotherapy is unclear in stage II colon cancer patients, delay in initiation of chemotherapy is associated with an incomplete chemotherapy course and poorer survival, especially cancer-specific survival. Causal inference in the association between delayed initiation of chemotherapy and inferior survival requires further investigation.
PLoS ONE 09/2014; 9(9):e107993. DOI:10.1371/journal.pone.0107993 · 3.23 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Docetaxel (DTX) chemotherapy remains a standard-of-care for metastatic castration-resistant prostate cancer (CRPC). DTX modestly increases survival, yet results in frequent occurrence of side-effects and resistant disease. An alternate chemotherapy with greater efficacy and minimal side-effects is needed. Acquisition of metabolic aberrations promoting increased survival and metastasis in CRPC cells include constitutive activation of Akt, loss of adenosine monophosphate-activated protein kinase (AMPK) activity due to Ser-485/491 phosphorylation, and over-expression of 3-hydroxy-3-methylglutaryl-Coenzyme A reductase (HMG-CoAR). We report that combination of simvastatin (SIM) and metformin (MET), within pharmacological dose range (500nM to 4microM SIM and 250microM to 2mM MET), significantly and synergistically reduces C4-2B3/B4 CRPC cell viability and metastatic properties with minimal adverse effects on normal prostate epithelial cells. Combination of SIM and MET decreased Akt Ser-473 and Thr-308 phosphorylation and AMPKalpha Ser-485/491 phosphorylation, increased Thr-172 phosphorylation and AMPKalpha activity as assessed by increased Ser-79 and Ser-872 phosphorylation of acetyl-CoA carboxylase and HMG-CoAR, respectively; decreased HMG-CoAR activity, and reduced total cellular cholesterol and its synthesis in both cell lines. Studies of C4-2B4 orthotopic NCr-nu/nu mice further demonstrated that combination of SIM and MET (3.5-7.0microg/g body weight SIM and 175-350microg/g body weight MET) daily by oral gavage over 9-week period significantly inhibited primary ventral prostate tumor formation, cachexia, bone metastasis, and biochemical failure more effectively than 24microg/g body weight DTX intraperitoneally-injected every three weeks, 7.0microg/g/day SIM, or 350microg/g/day MET treatment alone, with significantly less toxicity and mortality than DTX, establishing combination SIM and MET as a promising chemotherapeutic alternative for metastatic CRPC.
Molecular Cancer Therapeutics 08/2014; 13(10). DOI:10.1158/1535-7163.MCT-14-0451 · 5.68 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Unlabelled:
The effects of heightened microbial translocation on B cells during HIV infection are unknown. We examined the in vitro effects of HIV and lipopolysaccharide (LPS) on apoptosis of CD27+ IgD- memory B (mB) cells from healthy controls. In vivo analysis was conducted on a cohort of 82 HIV+ donors and 60 healthy controls. In vitro exposure of peripheral blood mononuclear cells (PBMCs) to LPS and HIV led to mB cell death via the Fas/Fas ligand (FasL) pathway. Plasmacytoid dendritic cells (pDCs) produced FasL in response to HIV via binding to CD4 and chemokine coreceptors. HIV and LPS increased Fas expression on mB cells in PBMCs, which was dependent on the presence of pDCs and monocytes. Furthermore, mB cells purified from PBMCs and pretreated with both HIV and LPS were more sensitive to apoptosis when cocultured with HIV-treated pDCs. Blocking the interferon receptor (IFNR) prevented HIV-stimulated FasL production in pDCs, HIV-plus-LPS-induced Fas expression, and apoptosis of mB cells. In vivo or ex vivo, HIV+ donors have higher levels of plasma LPS, Fas expression on mB cells, and mB cell apoptosis than controls. Correspondingly, in HIV+ donors, but not in controls, a positive correlation was found between plasma FasL and HIV RNA levels and between Fas expression on mB cells and plasma LPS levels. This work reveals a novel mechanism of mB cell apoptosis mediated by LPS and HIV through the Fas/FasL pathway, with key involvement of pDCs and type I IFN, suggesting a role for microbial translocation in HIV pathogenesis.
This study demonstrates that lipopolysaccharide (LPS) and type I interferon (IFN) play an important role in memory B cell apoptosis in HIV infection. It reveals a previously unrecognized role of microbial translocation in HIV pathogenesis.
Journal of Virology 07/2014; 88(19). DOI:10.1128/JVI.00682-14 · 4.44 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Effective antiretroviral therapy (ART) dramatically reduces AIDS-related complications, yet the life expectancy of long-term ART-treated HIV-infected patients remains shortened compared to that of uninfected controls, due to increased risk of non-AIDS related morbidities. Many propose that these complications result from translocated microbial products from the gut that stimulate systemic inflammation - a consequence of increased intestinal paracellular permeability that persists in this population. Concurrent intestinal immunodeficiency and structural barrier deterioration are postulated to drive microbial translocation, and direct evidence of intestinal epithelial breakdown has been reported in untreated pathogenic SIV infection of rhesus macaques. To assess and characterize the extent of epithelial cell damage in virally-suppressed HIV-infected patients, we analyzed intestinal biopsy tissues for changes in the epithelium at the cellular and molecular level. The intestinal epithelium in the HIV gut is grossly intact, exhibiting no decreases in the relative abundance and packing of intestinal epithelial cells. We found no evidence for structural and subcellular localization changes in intestinal epithelial tight junctions (TJ), but observed significant decreases in the colonic, but not terminal ileal, transcript levels of TJ components in the HIV+ cohort. This result is confirmed by a reduction in TJ proteins in the descending colon of HIV+ patients. In the HIV+ cohort, colonic TJ transcript levels progressively decreased along the proximal-to-distal axis. In contrast, expression levels of the same TJ transcripts stayed unchanged, or progressively increased, from the proximal-to-distal gut in the healthy controls. Non-TJ intestinal epithelial cell-specific mRNAs reveal differing patterns of HIV-associated transcriptional alteration, arguing for an overall change in intestinal epithelial transcriptional regulation in the HIV colon. These findings suggest that persistent intestinal epithelial dysregulation involving a reduction in TJ expression is a mechanism driving increases in colonic permeability and microbial translocation in the ART-treated HIV-infected patient, and a possible immunopathogenic factor for non-AIDS related complications.
[Show abstract][Hide abstract] ABSTRACT: Targeting most-at-risk individuals with HIV preventive interventions is cost-effective. We developed gender-specific indices to measure risk of HIV among sexually active individuals in Rakai, Uganda.
We used multivariable Cox proportional hazards models to estimate time-to-HIV infection associated with candidate predictors. Reduced models were determined using backward selection procedures with Akaike's information criterion (AIC) as the stopping rule. Model discrimination was determined using Harrell's concordance index (c index). Model calibration was determined graphically. Nomograms were used to present the final prediction models.
We used samples of 7,497 women and 5,783 men. 342 new infections occurred among females (incidence 1.11/100 person years,) and 225 among the males (incidence 1.00/100 person years). The final model for men included age, education, circumcision status, number of sexual partners, genital ulcer disease symptoms, alcohol use before sex, partner in high risk employment, community type, being unaware of a partner's HIV status and community HIV prevalence. The Model's optimism-corrected c index was 69.1 percent (95% CI = 0.66, 0.73). The final women's model included age, marital status, education, number of sex partners, new sex partner, alcohol consumption by self or partner before sex, concurrent sexual partners, being employed in a high-risk occupation, having genital ulcer disease symptoms, community HIV prevalence, and perceiving oneself or partner to be exposed to HIV. The models optimism-corrected c index was 0.67 (95% CI = 0.64, 0.70). Both models were well calibrated.
These indices were discriminative and well calibrated. This provides proof-of-concept that population-based HIV risk indices can be developed. Further research to validate these indices for other populations is needed.
PLoS ONE 04/2014; 9(4):e92015. DOI:10.1371/journal.pone.0092015 · 3.23 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Background/purpose:
This study was designed to evaluate the response and toxicity of sorafenib alone or when combined with carboplatin and paclitaxel in patients with platinum-sensitive, recurrent ovarian cancer, fallopian tube cancer, or primary peritoneal cancer (EOC).
Patients with recurrent platinum-sensitive EOC with no more than 2 prior courses of chemotherapy were randomized to single-agent sorafenib 400 mg twice daily or combination sorafenib 400 mg bid (days 2-19) with IV carboplatin (AUC 6) and IV paclitaxel 175 mg/m(2) (S+C/T) every 3 weeks. Single agent sorafenib could cross over to combination upon progression.
Patients were initially randomized to either arm, however, due to poor accrual, sorafenib arm was prematurely closed. A total of 13 patients were evaluable for response to sorafenib and 23 patients were evaluable for response to S+C/T. Objective response rate (RR) was 15 % for patients on sorafenib vs. 61 % for patients on S+C/T (p = 0.014); stable disease was seen in 62 % and 35 %, respectively. Clinical benefit rate (CBR) at 4 months (mos.) was 69 % for S and 65 % for S+C/T. The median progression free survival was 5.6 months on sorafenib vs. 16.8 months on S+C/T (p = 0.012) and there was no significant difference of overall survival between two arms (p = 0.974) with median overall survival 25.6 months under sorafenib vs. 25.9 months on S+C/T. Patients remained on trial for a median of 7.8 cycles on sorafenib and 5.4 cycles on S+C/T.
Sorafenib, alone or in combination with carboplatin and paclitaxel, has activity in patients with platinum-sensitive EOC. Sorafenib in combination with carboplatin and paclitaxel improved RR and PFS; however, there were increased grade and frequencies of toxicities.
Investigational New Drugs 03/2014; 32(4). DOI:10.1007/s10637-014-0078-5 · 2.92 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Dysfunction of the apoptotic pathway in prostate cancer cells confers apoptosis resistance towards various therapies. A novel strategy to overcome resistance is to directly target the apoptotic pathway in cancer cells. Apigenin, an anticancer agent, selectively toxic to cancer cells induces cell cycle arrest and apoptosis through mechanisms which are not fully explored. In the present study we provide novel insight into the mechanisms of apoptosis induction by apigenin. Treatment of androgen-refractory human prostate cancer PC-3 and DU145 cells with apigenin resulted in dose-dependent suppression of XIAP, c-IAP1, c-IAP2 and survivin protein levels. Apigenin treatment resulted in significant decrease in cell viability and apoptosis induction with the increase of cytochrome C in time-dependent manner. These effects of apigenin were accompanied by decrease in Bcl-xL and Bcl-2 and increase in the active form of Bax protein. The apigenin-mediated increase in Bax was due to dissociation of Bax from Ku70 which is essential for apoptotic activity of Bax. Apigenin treatment resulted in the inhibition of class I histone deacetylases and HDAC1 protein expression, thereby increasing the acetylation of Ku70 and the dissociation of Bax resulting in apoptosis of cancer cells. Furthermore, apigenin significantly reduced HDAC1 occupancy at the XIAP promoter, suggesting that histone deacetylation might be critical for XIAP downregulation. These results suggest that apigenin targets inhibitor of apoptosis proteins and Ku70-Bax interaction in the induction of apoptosis in prostate cancer cells and in athymic nude mouse xenograft model endorsing its in vivo efficacy.