IGFBP-3 nuclear localization predicts human prostate cancer recurrence.

Insulin-like growth factor binding protein-3 (IGFBP-3) is a pro-apoptotic, anti-metastasic, and anti-angiogenic protein. Low serum IGFBP-3 has been associated with risk of more aggressive prostate cancer (PCa). We investigated the impact of nuclear and cytoplasmic IGFBP-3 protein expression levels in PCa by examining their in situ expression across a wide spectrum of primary tumors by immunohistochemical analysis of tissue microarrays. Immunohistochemistry was performed on PCa microarrays constructed from 226 hormone naïve patients who underwent radical prostatectomy. Both cytoplasmic and nuclear IGFBP-3 expressions were scored in a semi-quantitative fashion using an integrated measure of intensity and positivity. The distribution of IGFBP-3 protein expression was examined across the spectrum of epithelial tissues, and its association with standard clinicopathological covariates and tumor recurrence was examined. There was a broad range of IGFBP-3 staining across all histologies examined. Tumor had higher IGFBP-3 cytoplasmic and nuclear staining than benign histologies. For IGFBP-3 nuclear staining, PCa was significantly different than benign prostatic hyperplasia, normal prostate, and prostate intraepithelial neoplasia. As both a continuous and dichotomized variable, higher nuclear IGFBP-3 expression had statistically significant associations with PCa recurrence. The cytoplasmic staining had no significance in any patient subgroup. In patients with low-grade cancer, IGFBP-3 nuclear positivity was a better predictor of recurrence than baseline PSA, tumor margin status, TNM tumor stage, or presence of capsular invasion. High nuclear IGFBP-3 is amongst the strongest predictors of cancer recurrence in patients with low-grade prostate cancers and may therefore play an important role in risk stratification.

Cellular histone modification patterns predict prognosis and treatment response in resectable pancreatic adenocarcinoma: results from RTOG 9704.

PURPOSE Differences in cellular levels of histone modifications have predicted clinical outcome in certain cancers. Here, we studied the prognostic and predictive value of three histone modifications in pancreatic adenocarcinoma. METHODS Tissue microarrays (TMAs) from two pancreatic adenocarcinoma cohorts were examined, including those from a 195-patient cohort from Radiation Therapy Oncology Group trial RTOG 9704, a multicenter, phase III, randomized treatment trial comparing adjuvant gemcitabine with fluorouracil and a 140-patient cohort of patients with stage I or II cancer from University of California, Los Angeles Medical Center. Immunohistochemistry was performed for histone H3 lysine 4 dimethylation (H3K4me2), histone H3 lysine 9 dimethylation (H3K9me2), and histone H3 lysine 18 acetylation (H3K18ac). Positive tumor cell staining for each histone modification was used to classify patients into low- and high-staining groups, which were related to clinicopathologic parameters and clinical outcome measures. Results Low cellular levels of H3K4me2, H3K9me2, or H3K18ac were each significant and independent predictors of poor survival in univariate and multivariate models, and combined low levels of H3K4me2 and/or H3K18ac were the most significant predictor of overall survival (hazard ratio, 2.93; 95% CI, 1.78 to 4.82) in the University of California, Los Angeles cohort. In subgroup analyses, histone levels were predictive of survival specifically for those patients with node-negative cancer or for those patients receiving adjuvant fluorouracil, but not gemcitabine, in RTOG 9704. CONCLUSION Cellular levels of histone modifications define previously unrecognized subsets of patients with pancreatic adenocarcinoma with distinct epigenetic phenotypes and clinical outcomes and represent prognostic and predictive biomarkers that could inform clinical decisions, including the use of fluorouracil chemotherapy.

Global levels of histone modifications predict prognosis in different cancers.

Cancer cells exhibit alterations in histone modification patterns at individual genes and globally at the level of single nuclei in individual cells. We demonstrated previously that lower global/cellular levels of histone H3 lysine 4 dimethylation (H3K4me2) and H3K18 acetylation (ac) predict a higher risk of prostate cancer recurrence. Here we show that the cellular levels of both H3K4me2 and H3K18ac also predict clinical outcome in both lung and kidney cancer patients, with lower levels predicting significantly poorer survival probabilities in both cancer groups. We also show that lower cellular levels of H3K9me2, a modification associated with both gene activity and repression, is also prognostic of poorer outcome for individuals with either prostate or kidney cancers. The predictive power of these histone modifications was independent of tissue-specific clinicopathological variables, the proliferation marker Ki-67, or a p53 tumor suppressor mutation. Chromatin immunoprecipitation experiments indicated that the lower cellular levels of histone modifications in more aggressive cancer cell lines correlated with lower levels of modifications at DNA repetitive elements but not with gene promoters across the genome. Our results suggest that lower global levels of histone modifications are predictive of a more aggressive cancer phenotype, revealing a surprising commonality in prognostic epigenetic patterns of adenocarcinomas of different tissue origins.

MAGE-B2 autoantibody: a new biomarker for pediatric systemic lupus erythematosus.

OBJECTIVE: Melanoma-associated antigen gene B2 (MAGE-B2) encodes an embryonic antigen normally silenced after birth except in testis and placenta. We identified the MAGE-B2 gene and autoantibodies in pediatric patients with systemic lupus erythematosus (SLE) glomerulonephritis. We investigated the prevalence of MAGE-B2 autoantibodies in association with active SLE, to determine a pathogenetic role of MAGE-B2 protein through its distribution in cells and tissues. METHODS: A cross-sectional study analyzed the frequency of MAGE-B2 autoantibodies in 40 patients with pediatric SLE, 23 adult controls, and 16 patients with pediatric juvenile rheumatoid arthritis (JRA) using Western blots containing recombinant MAGE-B2. SLE Disease Activity Index 2000 (SLEDAI-2K) and British Isles Lupus Assessment Group (BILAG) index measured SLE disease activity. Tissue distribution of MAGE-B2 protein was assessed by immunohistochemistry, immunofluorescence, and Western blots. RESULTS: Seventeen (43%) of 40 pediatric SLE patients had MAGE-B2 autoantibodies as compared to 0 of 16 JRA patients and 2 of 23 adult controls. SLE disease activity was significantly higher in MAGE-B2 autoantibody-positive versus autoantibody-negative patients (SLEDAI-2K, mean 10.9 vs 5.2, p = 0.013; BILAG, mean 15.3 vs 6.3, p = 0.023). Active nephritis was more prevalent (60% vs 24%) in MAGE-B2 autoantibody-positive than autoantibody-negative SLE patients. MAGE-B2 protein was visualized in SLE kidney proximal convoluted tubules and in tumor epithelial cells, but not in lymphoblastoid cells. CONCLUSION: MAGE-B2 autoantibody appears to be a clinically relevant biomarker for pediatric SLE disease activity and nephritis.

Expression of arginase II in prostate cancer.

Previous reports have shown elevated arginase activity in prostate cancer patients. This study was designed to compare expression levels of arginase II (AII) in various human prostate cancer cell lines and tissues. Expression levels of AII and other enzymes involved in arginine metabolism were examined in androgen-dependent (LNCaP, LAPC-4) and androgen-independent (PC3, DU145, CL-1, CL-2) prostate cancer cell lines by real-time RT-PCR and Western blot analysis. Further expression analysis of AII was accomplished by immunohistochemical staining of a tissue microarray comprised of 246 primary prostatectomy specimens. In addition, polyamine levels were measured within the prostate cancer cell lines by HPLC. Total polyamines were significantly lower in the androgen-dependent cell lines compared to the androgen-independent cell lines. AII expression was found to be most prominent in the androgen-dependent cell lines and least prominent in the androgen-independent cell lines. Additionally, we found expression of ornithine aminotransferase (OAT), an enzyme also responsible for ornithine production, to be inversely correlated with AII expression. The tissue microarray data revealed that the highest AII expression was seen in BPH, followed by PIN and normal samples, with the lowest expression levels observed in prostate cancer tissues. Moreover, we observed an expression gradient across Gleason grades revealing stronger AII expression in low-grade tumors. The polyamine data, combined with the expression analysis studies, support a possible correlation between AII, OAT, and polyamine synthesis. Based on these results, arginase II expression may play a role in prostate cancer progression. More specifically, the elevated AII expression seen in androgen-dependent and in more differentiated prostate cancers suggests that AII could be a potentially useful marker of early stage prostate adenocarcinoma.

Na,K-adenosine triphosphatase alpha1-subunit predicts survival of renal clear cell carcinoma.

PURPOSE: Na,K-adenosine triphosphatase, which is composed of a catalytic alpha-subunit and a regulatory beta-subunit, generates an electrochemical gradient across the plasma membrane. Previous studies demonstrated altered Na,K-adenosine triphosphatase subunit expression in renal clear cell carcinoma and an association of subunit levels with the prediction of recurrent bladder cancer. We determined the clinical association of protein expression patterns of the Na,K-adenosine triphosphatase alpha1 and beta1-subunits in renal clear cell carcinoma using tissue microarrays with linked clinicopathological data. MATERIALS AND METHODS: The UCLA kidney cancer tissue microarray was used to investigate the protein expression of Na,K-adenosine triphosphatase alpha1 and beta1-subunits by immunohistochemistry in 342 patients with renal clear cell carcinoma who were treated with radical nephrectomy. Of these patients clinical outcomes studies were performed in 317. The resultant expression reactivity was correlated with clinicopathological variables. RESULTS: We found that the alpha1-subunit was a significant and independent predictor of disease specific death from renal clear cell carcinoma on multivariate Cox proportional hazards analysis that included established prognostic factors Eastern Cooperative Oncology Group performance status, pT status, metastasis status and tumor grade. Significance was found when examining all patients with clear cell renal cell carcinoma as well as patient substrata with low or high grade tumors and localized or metastatic disease, suggesting that the Na,K-adenosine triphosphatase alpha1-subunit could be used as a new prognosticator for disease specific death from renal clear cell carcinoma. CONCLUSIONS: These results suggest that Na,K-adenosine triphosphatase alpha1-subunit expression patterns may be a useful clinical prognosticator for renal clear cell carcinoma. The Na,K-adenosine triphosphatase beta1-subunit was not found to be a useful prognosticator in this setting.

Global histone modification patterns predict risk of prostate cancer recurrence.

Aberrations in post-translational modifications of histones have been shown to occur in cancer cells but only at individual promoters; they have not been related to clinical outcome. Other than being targeted to promoters, modifications of histones, such as acetylation and methylation of lysine and arginine residues, also occur over large regions of chromatin including coding regions and non-promoter sequences, which are referred to as global histone modifications. Here we show that changes in global levels of individual histone modifications are also associated with cancer and that these changes are predictive of clinical outcome. Through immunohistochemical staining of primary prostatectomy tissue samples, we determined the percentage of cells that stained for the histone acetylation and dimethylation of five residues in histones H3 and H4. Grouping of samples with similar patterns of modifications identified two disease subtypes with distinct risks of tumour recurrence in patients with low-grade prostate cancer. These histone modification patterns were predictors of outcome independently of tumour stage, preoperative prostate-specific antigen levels, and capsule invasion. Thus, widespread changes in specific histone modifications indicate previously undescribed molecular heterogeneity in prostate cancer and might underlie the broad range of clinical behaviour in cancer patients.

Epithelial cell adhesion molecule (KSA) expression: pathobiology and its role as an independent predictor of survival in renal cell carcinoma.

PURPOSE: Epithelial cell adhesion molecule (EpCAM) is a widely expressed adhesion molecule in epithelial cancers. The purpose of this study is to determine the protein expression patterns of EpCAM in renal cell carcinoma (RCC) using tissue arrays linked to a clinicopathological database to evaluate both its predictive power in patient stratification and its suitability as a potential target for immunotherapeutic treatment strategies. EXPERIMENTAL DESIGN: The University of California, Los Angeles kidney cancer tissue microarray contains specimens from 417 patients treated with nephrectomy. EpCAM protein expression in tumors and matched morphologically normal renal tissues was evaluated using anti-EpCAM immunohistochemistry. The resultant expression reactivity was correlated with clinicopathological variables. RESULTS: EpCAM is consistently expressed in the distal nephron on normal renal epithelium. Clear cell RCCs show minimal and infrequent EpCAM expression, whereas chromophobe and collecting duct RCCs both demonstrate intense and frequent expression. Of 318 clear cell carcinomas used in the analysis, 10% were EpCAM positive in > or = 50% of cells, and 8% of patients would be considered candidates for EpCAM-based therapy, based on high expression [> or = moderate intensity and frequent (> or = 50%) expression] and the need for systemic treatment. EpCAM expression was an independent prognostic factor for improved disease-specific survival, with a multivariate hazard ratio of 0.63 (P = 0.017; 95% confidence interval, 0.43-0.92). CONCLUSIONS: EpCAM is a novel prognostic molecular marker in RCC patients, and its positive expression is an independent predictor associated with improved survival. However, high expression in morphologically normal renal tissues and minimal or absent expression in clear cell carcinomas will likely limit the utility of this epithelial marker in targeted treatments of this most common RCC type.