Faculty Bibliography

Treatment protocols for breast cancer depend predominantly on receptor status with respect to estrogen (estrogen receptor alpha), progesterone (progesterone receptor) and human epidermal growth factor [human epidermal growth factor receptor 2 (HER2)]. The presence of one or more of these receptors suggests that a treatment targeting these pathways might be effective, while the absence of, or in the case of HER2, lack of overexpression of, all of these receptors, termed triple negative breast cancer (TNBC), indicates a need for the more toxic chemotherapy. In an effort to develop targeted therapies for TNBC, it will be necessary to differentiate among specific TNBC subtypes. The subset of TNBC that expresses androgen receptor (AR) has been determined to express genes consistent with a luminal subtype and therefore may be amenable to therapies targeting either AR, itself, or other pathways typical of a luminal subtype. Recent investigations of the AR signal pathway within breast cancer lead to AR as a significant target for breast cancer therapy with several clinical trials currently in progress. The subclass of TNBC that lacks AR, which we have termed quadruple negative breast cancer (QNBC) currently lacks a defined targetable pathway. Unlike AR-positive TNBC, QNBC predominantly exhibits a basal-like molecular subtype. Several subtypes and related pathway proteins are preferentially expressed in QNBC that may serve as effective targets for treatment, such as ACSL4, SKP2 and EGFR. ACSL4 expression has been demonstrated to be inversely correlated with expression of hormone/growth factor receptors and may thus serve as a biomarker for QNBC as well as a target for therapy. In the following review we summarize some of the current efforts to develop alternatives to chemotherapy for TNBC and QNBC.

This study aimed to detect protein changes that can assist to understand the underlying biology of bladder cancer. The data showed forty five proteins were found to be differentially expressed comparing tumors vs non-tumor tissues, of which EGFR and cdc2p34 were correlated with muscle invasion and histological grade. Ten proteins (ss-catenin, HSP70, autotaxin, Notch4, PSTPIP1, DPYD, ODC, cyclinB1, calretinin and EPO) were able to classify muscle invasive BCa (MIBC) into 2 distinct groups, with group 2 associated with poorer survival. Finally, 3 proteins (P2X7, cdc25B and TFIIH p89) were independent factors for favorable overall survival.

We recently demonstrated that anti-SSA/52kD-Ro antibodies (Abs) from patients with autoimmune-diseases and QTc prolongation directly target and inhibit HERG-K channel at the extracellular pore region (E-pore) where homology with SSA/52kD-Ro antigen was demonstrated. We tested the hypothesis that immunization of guinea-pigs with a peptide corresponding to the E-pore region (E-pore peptide) will generate pathogenic inhibitory Abs and cause QTc prolongation. Guinea-pigs were immunized with a 31-amino-acid peptide corresponding to E-pore region of HERG. At days 10 to 62 post-immunization, ECGs were recorded and blood drawn for the detection of E-pore peptide Abs. Sera from patients with autoimmune-diseases was evaluated for reactivity to E-pore peptide by ELISA and histology was performed on hearts using Masson's trichrome. HERG channel inhibition was assessed by electrophysiology and by computational modelling of Human ventricular action potential (AP). ELISA results revealed the presence of high-titers of E-pore peptide Abs and significant QTc prolongation post-immunization. High reactivity to E-pore peptide was found using anti-SSA/Ro Ab positive-sera from patients with QTc prolongation. Histology data showed no evidence of fibrosis in immunized hearts. Simulations of simultaneous inhibition of repolarizing currents by anti-SSA/Ro Ab positive-sera showed predominance of HERG channel in controlling AP duration and QT-interval. The results are first to demonstrate that inhibitory Abs to HERG E-pore region induced QTc prolongation in immunized guinea-pigs by targeting HERG channel independently from fibrosis. The reactivity of anti-SSA/Ro Ab positive-sera from patients with connective tissue diseases with the E-pore peptide opens novel pharmacotherapy avenues in the diagnosis and management of autoimmune-associated QTc prolongation

The current substage classification of pT2 prostate cancer (AJCC, 7th edition, 2010) into pT2a (unilateral tumors <1/2 of lobe), pT2b (unilateral tumors >/=1/2 of lobe) and pT2c (bilateral tumors) is of questionable relevance. Many studies show no difference in prognosis between substages, and incidence of pT2b prostate cancer is low. Other classification systems have been proposed based on tumor volume, as measured by dominant nodule size or tumor percentage. We characterized pT2b tumors and assessed utility of current pT2 substaging in predicting biochemical recurrence-free survival after radical prostatectomy and compared with different substaging methods based on tumor volume. Patients with pT2 tumors were selected among patients who underwent radical prostatectomy from 1998 to 2008. Dominant nodule size was dichotomized as <1.6 cm vs. >/=1.6 cm. Tumor percentage was dichotomized as 25%. Kaplan-Meier analysis and multivariate Cox proportional hazard regression models were used to evaluate pathological parameters predictive of biochemical recurrence-free survival. 785 patients met criteria, of which 145 (18.5%) were pT2a, 15 (1.9%) were pT2b and 625 (79.6%) were pT2c. The pT2 substages were not significant predictors of biochemical recurrence-free survival on univariate or multivariate analysis. In a multivariate model, tumor percentage>25% (p=0.002) was associated with decreased biochemical recurrence-free survival. In patients with stage pT2 prostate cancer, the current substaging method lacks predictive value for biochemical recurrence-free survival after accounting for other pathologic and clinical predictors. However, tumor percentage (25%) is a promising approach to substaging of pT2 prostate cancer.

TBLR1/TBL1XR1, a core component of the nuclear receptor corepressor (NCoR) complex critical for the regulation of multiple nuclear receptors, is a transcriptional coactivator of androgen receptor (AR) and functions as a tumor suppressor when expressed in the nucleus in prostate. Subcellular localization of a protein is critical for its function, and although TBLR1, as a transcriptional cofactor, has been primarily viewed as a nuclear protein, many cells also express variable levels of cytoplasmic TBLR1 and its cytoplasmic specific functions have not been studied. Prostate cancer (PCa) cells express moderately higher level of cytoplasmic TBLR1 compared to benign prostate cells. When comparing androgen-dependent (AD) to androgen-independent (AI) PCa, AI cells contain very high levels of TBLR1 cytoplasmic expression and low levels of nuclear expression. Overexpression of cytoplasmic TBLR1 in AD cells inhibits apoptosis induced by androgen deprivation therapy, either in an androgen free condition or in the presence of bicalutamide. Additionally, we identified a cytoplasmic specific isoform of TBLR1 (cvTBLR1) approximately 5 kDa lower in molecular weight, that is expressed at higher levels in AI PCa cells. By immunoprecipitation, we purified cvTBLR1 and using mass spectrometry analysis combined with N-terminal TMPP labeling and Edman degradation, we identified the cleavage site of cvTBLR1 at amino acid 89, truncating the first 88 amino acids of the N-terminus of the full length protein. Functionally, cvTBLR1 expressed in the cytoplasm reduced apoptosis in PCa cells and promoted growth, migration, and invasion. Finally, we identified a nuclear export signal sequence for TBLR1 cellular localization by deletion and site-directed mutagenesis. The roles of TBLR1 and cvTBLR1 provide novel insights into the mechanism of castration resistance and new strategies for PCa therapy.

BACKGROUND: The human papilloma virus (HPV) is a carcinogen known for its strong association with cervical cancers and cervical lesions. It is also known to be associated with a variety of squamous cell carcinomas in other areas, such as the penis, vulva, anus and head and neck. However, the association with urothelial carcinoma remains controversial. Here, we report a case of urothelial carcinoma with squamous differentiation associated with HPV-6/HPV-11. CASE PRESENTATION: This is a case of a 70 year old man who presented with nocturia and pressure during urination. During the TURP procedure for what was clinically thought to be benign prostate hyperplasia with pathologic diagnosis as prostate carcinoma, a 2 cm papillary mass was found in the distal penile urethra. The papillary mass was found to be a high grade urothelial carcinoma positive for GATA 3 expression, with focal areas of squamous differentiation. The areas with squamous differentiation demonstrated koilocytic differentiation, which were positive for strong p16 expression. The tumor was found to harbor low risk HPV 6/11 by in situ hybridization. CONCLUSIONS: This study case demonstrates HPV infection with a low risk subtype (HPV 6/11) associated with an urothelial carcinoma with squamous differentiation and condylomatous features.

Alpha-fetoprotein (AFP) producing gastric adenocarcinoma is considered as a rare subtype of gastric adenocarcinoma. Compared with AFP non-producing gastric adenocarcinoma, our study and other previous studies showed that AFP producing gastric adenocarcinoma is more aggressive and prone to liver metastasis. Using the Protein Pathway Array, 11 of out of 286 proteins tested were found to be differentially expressed between AFP producing (n=32) and AFP non-producing (n=45) gastric adenocarcinoma tissues. In addition, the high level expression of XIAP and IGF-Irbeta in gastric adenocarcinoma tissues was independent factors for poor prognosis in AFP producing gastric adenocarcinoma patients. A risk model based on the XIAP and IGF-Irbeta expression levels can separate AFP producing gastric adenocarcinoma patients into 2 subgroups and each subgroup had a distinct set of signaling pathways involved. In conclusion, AFP producing gastric adenocarcinoma is a heterogeneous cancer with different clinical outcomes, biological behaviors and underlying molecular alterations.