Genistein chemoprevention of prostate cancer in TRAMP mice

Epidemiological studies suggest an inverse association between soy intake and prostate cancer risk. Genistein, the predominant phytoestrogen in soy food, has been proposed as a potential chemopreventive agent due to its anti-estrogen and tyrosine kinase inhibitory effects. To determine the most effective period for genistein chemoprevention, the Transgenic adenocarcinoma mouse prostate (TRAMP) model was used. The treatments were 250 mg genistein/kg AIN-76A diet 1) prepubertally only, 2) in adulthood only or 3) through out life. Controls received AIN-76A diet. By 28 weeks of age, 100% TRAMP mice fed control diet developed prostatic intraepithelial neoplasia (PIN) or adenocarcinomas with 6%, 16%, 44% and 34% developing high grade PIN, well differentiated, moderately differentiated and poorly differentiated prostatic adenocarcinomas, respectively. Prepubertal only (1–35 days postpartum) and adult only genistein treatments (12 – 28 weeks) resulted in 6% and 29% decreases in poorly-differentiated cancerous lesions compared with controls, respectively. The most significant effect was seen in the TRAMP mice exposed to genistein throughout life (1–28 weeks) with a 50% decrease in poorly-differentiated cancerous lesions. In a separate experiment in castrated TRAMP mice, dietary genistein suppressed the development of advanced prostate cancer by 35% compared with controls. Of the tumors that developed in castrated TRAMP mice, 100% were poorly-differentiated in contrast to the 37% of noncastrated TRAMP mice that developed poorly-differentiated tumors. ICI 182,780 (ICI), genistein and estrogen down-regulated androgen receptor (AR), estrogen receptor alpha (ER-α) and progesterone receptor (PR) in the prostates of C57BL/6 mice, and act independently of ER. Our data obtained in intact and castrated transgenic mice suggest that genistein may be a promising chemopreventive agent against androgen-dependent and independent prostate cancers

Interactions between Cells with Distinct Mutations in c-MYC and Pten in Prostate Cancer

In human somatic tumorigenesis, mutations are thought to arise sporadically in individual cells surrounded by unaffected cells. This contrasts with most current transgenic models where mutations are induced synchronously in entire cell populations. Here we have modeled sporadic oncogene activation using a transgenic mouse in which c-MYC is focally activated in prostate luminal epithelial cells. Focal c-MYC expression resulted in mild pathology, but prostate-specific deletion of a single allele of the Pten tumor suppressor gene cooperated with c-MYC to induce high grade prostatic intraepithelial neoplasia (HGPIN)/cancer lesions. These lesions were in all cases associated with loss of Pten protein expression from the wild type allele. In the prostates of mice with concurrent homozygous deletion of Pten and focal c-MYC activation, double mutant (i.e. c-MYC+;Pten-null) cells were of higher grade and proliferated faster than single mutant (Pten-null) cells within the same glands. Consequently, double mutant cells outcompeted single mutant cells despite the presence of increased rates of apoptosis in the former. The p53 pathway was activated in Pten-deficient prostate cells and tissues, but c-MYC expression shifted the p53 response from senescence to apoptosis by repressing the p53 target gene p21Cip1. We conclude that c-MYC overexpression and Pten deficiency cooperate to promote prostate tumorigenesis, but a p53-dependent apoptotic response may present a barrier to further progression. Our results highlight the utility of inducing mutations focally to model the competitive interactions between cell populations with distinct genetic alterations during tumorigenesis

Cervical Precancer Risk in HIV-Infected Women Who Test Positive for Oncogenic Human Papillomavirus Despite a Normal Pap Test

Background. Determining cervical precancer risk among human immunodeficiency virus (HIV)–infected women who despite a normal Pap test are positive for oncogenic human papillomavirus (oncHPV) types is important for setting screening practices

Synchronous and metachronous bilateral breast cancer: clinicopathologic characteristics and prognostic outcomes

The incidence of bilateral breast cancer (BBC) reportedly ranges from 1.4 to 11.8%. Women with a first primary breast cancer are at a 2- to 6-fold increased risk of developing contralateral BC. However, there have been limited studies analyzing the clinicopathologic features of BBC and conflicting data exist on the prognostic significance of BBC. In this study, we sought to analyze the incidence of BBC in the era of modern medicine and assess the clinicopathologic characteristics and prognostic outcomes compared to unilateral BC (UBC). Of the 5941 patients with stage I-III BC diagnosed between 1998 and 2013 at our institution, 110 developed BBC, including 58 synchronous BBC (SBBC, interval between the first and the contralateral BC ≤3 months) and 52 metachronous BBC (MBBC, interval \u3e3 months). The median time to the second tumor was 67.9 months among patients with MBBC. BBC was associated with a significantly lower rate of having a ductal type, high grade, HER2-positive or node-positive disease when compared to UBC, while no difference was found for age, race, ER/PR status, or pathologic tumor stage. When compared to MBBC, SBBC was strongly associated with a lobular phenotype, non-high grade, and ER/PR-positive disease; and further demonstrated a significantly higher concordant rate for ER, PR, and HER2 status. Patients with BBC had a significantly worse distant relapse-free survival (RFS) but a similar disease-specific survival (DSS) when compared to those with UBC. Being African American, having a high histologic grade and higher pathologic tumor or node stage was significantly associated with a worse prognosis, while SBBC was associated with a favorable RFS by multivariate analysis. Nodal status was the only independent prognosticator for DSS in patients with BBC. Further investigation into the complex biologic and clinical behavior of BBC may provide novel insights into the therapeutic strategies in the pursuit of precision medicine in this unique subset of patients

Comparative analysis of triple-negative breast cancer transcriptomics of Kenyan, African American and Caucasian Women

a b s t r a c t : Purpose: : Triple-negative breast cancer (TNBC) patients of various ethnic groups often have discrete clinical presentations and outcomes. Women of African descent have a disproportionately higher chance of developing TNBCs. The aim of the current study was to establish the transcriptome of TNBCs from Kenyan (KE) women of Bantu origin and compare it to those TNBCs of African-Americans (AA) and Caucasians (CA) for identifying KE TNBC-specific molecular determinants of cancer progression and potential biomarkers of clinical outcomes. Patients and Methods: : Pathology-confirmed TNBC tissues from Kenyan women of Bantu origin (n = 15) and age and stage range matched AA (n = 19) and CA (n = 23) TNBCs of patients from Alabama were included in this study. RNA was isolated from paraffin-embedded tissues, and expression was analyzed by RNA sequencing. Results: : At clinical presentation, young KE TNBC patients have tumors of higher stages. Differential expression analysis identified 160 up-regulated and 178 down- regulated genes in KE TNBCs compared to AA and CA TNBCs. Validation analyses of the TCGA breast cancer data identified 45 KE TNBC-specific genes that are involved in the apoptosis (ACTC1, ERCC6 and CD14), cell proliferation (UHRF2, KDM4C, UHMK1, KCNH5, KRT18, CSF1R and S100A13), and Wnt signaling (BCL9L) pathways. Conclusions: : In this study, we identified biomarkers that are specific for KE TNBC patients of Bantu origin. Further study with a larger sample size of matched tumors could confirm our findings. If biologically confirmed, these molecular determinants could have clinical and biological implications and serve as targets for development of personalized therapeutics for KE TNBC patients

Epidemiological evidence that common HPV types may be common because of their ability to evade immune surveillance: Results from the Women's Interagency HIV study

Infection by human papillomavirus (HPV) type 16, the most oncogenic HPV type, was found to be the least affected by HIV-status and CD4 count of any of the approximately 13 oncogenic HPV types. This relative independence from host immune status has been interpreted as evidence that HPV16 may have an innate ability to avoid the effects of immunosurveillance. However, the impact of immune status on other individual HPV types has not been carefully assessed. We studied type-specific HPV infection in a cohort of 2,470 HIV-positive (HIV[+]) and 895 HIV-negative (HIV[-]) women. Semi-annually collected cervicovaginal lavages were tested for >40 HPV types. HPV type-specific prevalence ratios (PRs), incidence and clearance hazard ratios (HRs), were calculated by contrasting HPV types detected in HIV[+] women with CD4 < 200 to HIV[-] women. HPV71 and HPV16 prevalence had the weakest associations with HIV-status/CD4 count of any HPV, according to PRs. No correlations between PRs and HPV phylogeny or oncogenicity were observed. Instead, higher HPV type-specific prevalence in HIV[-] women correlated with lower PRs (ρ = -0.59; p = 0.0001). An alternative (quadratic model) statistical approach (P = a*P  + b*P ; R = 0.894) found similar associations (p = 0.0005). In summary, the most prevalent HPV types in HIV[-] women were the types most independent from host immune status. These results suggest that common HPV types in HIV[-] women may have a greater ability to avoid immune surveillance than other types, which may help explain why they are common