ERG, an ETS family transcription factor, is known to be expressed in endothelial cells, and oncogenic ERG gene fusions occur in subsets of prostatic carcinoma, acute myeloid leukemia, and Ewing ...sarcoma. In this study, we immunohistochemically investigated nuclear ERG expression using a new monoclonal antibody, CPDR ERG-MAb, that is highly specific for detecting ERG protein and ERG-expressing prostate carcinomas. A broad range of vascular endothelial (n = 250), other mesenchymal (n = 973), and epithelial tumors (n = 657) was examined to determine the use of ERG immunohistochemistry in surgical pathology. Only immunostains with ERG-positive normal endothelia (internal control) were considered valid, and only nuclear staining was considered to be positive. In adult tissues, ERG was restricted to endothelial cells and to a subset of bone marrow precursors, but early fetal mesenchyme and subpopulations of fetal cartilage were also positive. In vascular tumors, ERG was expressed in endothelia of all hemangiomas and lymphangiomas, and typically extensively expressed in 96 of 100 angiosarcomas, 42 of 43 epithelioid hemangioendotheliomas, and all 26 Kaposi sarcomas. Among nonvascular mesenchymal tumors, only blastic extramedullary myeloid tumors (7 of 10) and rare Ewing sarcomas (2 of 29) were positive. Among epithelial tumors, 30 of 66 prostatic adenocarcinomas showed focal-to-extensive ERG positivity, with no immunoreactivity in the normal prostate. Other carcinomas and epithelial tumors (n = 643) were ERG negative, with the exception of 1 of 42 large cell undifferentiated pulmonary carcinomas and 1 of 27 mesotheliomas, each of which showed focal nuclear ERG positivity. On the basis of the above observations, ERG is a highly specific new marker for benign and malignant vascular tumors. Among epithelial tumors, ERG shows a great promise as a marker to identify prostatic carcinoma in both primary and metastatic settings.
In prostate cancer, emerging data highlight the role of DNA damage repair genes (DDRGs) in aggressive forms of the disease. However, DDRG mutations in African American men are not yet fully defined. ...Here, we profile germline mutations in all known DDRGs (N = 276) using whole genome sequences from blood DNA of a matched cohort of patients with primary prostate cancer comprising of 300 African American and 300 European Ancestry prostate cancer patients, to determine whether the mutation status can enhance patient stratification for specific targeted therapies. Here, we show that only 13 of the 46 DDRGs identified with pathogenic/likely pathogenic mutations are present in both African American and European ancestry patients. Importantly, RAD family genes (RAD51, RAD54L, RAD54B), which are potentially targetable, as well as PMS2 and BRCA1, are among the most frequently mutated DDRGs in African American, but not in European Ancestry patients.
Abstract
Prostate-specific antigen (PSA) screening for prostate cancer (PCa) is limited by the lack of specificity but is further complicated in the benign prostatic hyperplasia (BPH) population ...which also exhibit elevated PSA, representing a clear unmet need to distinguish BPH from PCa. Herein, we evaluated the utility of FLNA IP-MRM, age, and prostate volume to stratify men with BPH from those with PCa. Diagnostic performance of the biomarker panel was better than PSA alone in discriminating patients with negative biopsy from those with PCa, as well as those who have had multiple prior biopsies (AUC 0.75 and 0.87 compared to AUC of PSA alone 0.55 and 0.57 for patients who have had single compared to multiple negative biopsies, respectively). Of interest, in patients with PCa, the panel demonstrated improved performance than PSA alone in those with Gleason scores of 5–7 (AUC 0.76 vs. 0.56) and Gleason scores of 8–10 (AUC 0.74 vs. 0.47). With Gleason scores (8–10), the negative predictive value of the panel is 0.97, indicating potential to limit false negatives in aggressive cancers. Together, these data demonstrate the ability of the biomarker panel to perform better than PSA alone in men with BPH, thus preventing unnecessary biopsies.
Oncogenic activation of the ETS-related gene (
) by recurrent gene fusions (predominantly TMPRSS2-ERG) is one of the most validated and prevalent genomic alterations present in early stages of ...prostate cancer. In this study, we screened small-molecule libraries for inhibition of ERG protein in
harboring VCaP prostate cancer cells using an In-Cell Western Assay with the highly specific ERG-MAb (9FY). Among a subset of promising candidates, 1-2-Thiazolylazo-2-naphthol (NSC139021, hereafter ERGi-USU) was identified and further characterized. ERGi-USU selectively inhibited growth of ERG-positive cancer cell lines with minimal effect on normal prostate or endothelial cells or ERG-negative tumor cell lines. Combination of ERGi-USU with enzalutamide showed additive effects in inhibiting growth of VCaP cells. A screen of kinases revealed that ERGi-USU directly bound the ribosomal biogenesis regulator atypical kinase RIOK2 and induced ribosomal stress signature.
, ERGi-USU treatment inhibited growth of ERG-positive VCaP tumor xenografts with no apparent toxicity. Structure-activity-based derivatives of ERGi-USU recapitulated the ERG-selective activity of the parental compound. Taken together, ERGi-USU acts as a highly selective inhibitor for the growth of ERG-positive cancer cells and has potential for further development of ERG-targeted therapy of prostate cancer and other malignancies.
A highly selective small-molecule inhibitor of ERG, a critical driver of early stages of prostate cancer, will be imperative for prostate cancer therapy.
.
The identification of prostate transmembrane protein androgen induced 1 (
), an androgen responsive gene, came initially from the studies of androgen regulatory gene networks in prostate cancer. It ...was soon followed by the documentation of the expression and functional analysis of transmembrane prostate androgen-induced protein (
)/
in other solid tumors including renal, colon, breast, lung, and ovarian cancers. Further elucidation of
gene expression and sequence analysis revealed the presence of five isoforms with distinct extracellular domains (isoforms
,
,
,
, and
). Notably, the predicted amino acid sequences of PMEPA1 isoforms show differences at the N-termini, a conserved membrane spanning and cytoplasmic domains.
serves as an essential regulator of multiple signaling pathways including androgen and TGF-β signaling in solid tumors. Structure-function studies indicate that specific motifs present in the cytoplasmic domain (PY, SIM, SH3, and WW binding domains) are utilized to mediate isoform-specific functions through interactions with other proteins. The understanding of the "division of labor" paradigm exhibited by
isoforms further expands our knowledge of gene's multiple functions in tumorigenesis. In this review, we aim to summarize the most recent advances in understanding of
isoform-specific functions and their associations with prostate cancer progression, highlighting the potentials as biomarker and therapeutic target in prostate cancer.
Predicting the clinical course of prostate cancer is challenging due to the wide biological spectrum of the disease. The objective of our study was to identify prostate cancer prognostic markers in ...patients 'sera using a multi-omics discovery platform.
Pre-surgical serum samples collected from a longitudinal, racially diverse, prostate cancer patient cohort (N = 382) were examined. Linear Regression and Bayesian computational approaches integrated with multi-omics, were used to select markers to predict biochemical recurrence (BCR). BCR-free survival was modeled using unadjusted Kaplan-Meier estimation curves and multivariable Cox proportional hazards analysis, adjusted for key pathologic variables. Receiver operating characteristic (ROC) curve statistics were used to examine the predictive value of markers in discriminating BCR events from non-events. The findings were further validated by creating a training set (N = 267) and testing set (N = 115) from the cohort.
Among 382 patients, 72 (19%) experienced a BCR event in a median follow-up time of 6.9 years. Two proteins-Tenascin C (TNC) and Apolipoprotein A1V (Apo-AIV), one metabolite-1-Methyladenosine (1-MA) and one phospholipid molecular species phosphatidic acid (PA) 18:0-22:0 showed a cumulative predictive performance of AUC = 0.78 OR (95% CI) = 6.56 (2.98-14.40), P < 0.05, in differentiating patients with and without BCR event. In the validation set all four metabolites consistently reproduced an equivalent performance with high negative predictive value (NPV; > 80%) for BCR. The combination of pTstage and Gleason score with the analytes, further increased the sensitivity AUC = 0.89, 95% (CI) = 4.45-32.05, P < 0.05, with an increased NPV (0.96) and OR (12.4) for BCR. The panel of markers combined with the pathological parameters demonstrated a more accurate prediction of BCR than the pathological parameters alone in prostate cancer.
In this study, a panel of serum analytes were identified that complemented pathologic patient features in predicting prostate cancer progression. This panel offers a new opportunity to complement current prognostic markers and to monitor the potential impact of primary treatment versus surveillance on patient oncological outcome.
TP53 is one of the most frequently altered genes in prostate cancer. The precise assessment of its focal alterations in primary tumors by immunohistochemistry (IHC) has significantly enhanced its ...prognosis. p53 protein expression and lymphovascular invasion (LVI) were evaluated for predicting metastatic progression by IHC staining of representative whole-mounted prostate sections from a cohort of 189 radical prostatectomy patients with up to 20 years of clinical follow-up. Kaplan-Meier survival curves were used to examine time to distant metastasis (DM) as a function of p53 expression and LVI status. TP53 targeted sequencing was performed in ten tumors with the highest expression of p53 staining. Nearly half (49.8%) of prostate tumors examined showed focal p53 expression while 26.6% showed evidence of LVI. p53(+) tumors had higher pathologic T stage, Grade Group, Nuclear Grade, and more frequent LVI. p53 expression of > 5% and LVI, individually and jointly, are associated with poorer DM-free survival. TP53 mutations were detected in seven of ten tumors sequenced. Four tumors with the highest p53 expression harbored likely pathogenic or pathogenic mutations. High levels of p53 expression suggest the likelihood of pathogenic TP53 alterations and, together with LVI status, could enhance early prognostication of prostate cancer progression.
The oncogenic activation of the ETS-related gene (
) due to gene fusions is present in over half of prostate cancers in Western countries. Because of its high incidence and oncogenic role, ERG and ...components of ERG network have emerged as potential drug targets for prostate cancer. Utilizing gene expression datasets, from matched normal and prostate tumor epithelial cells, an association of NOTCH transcription factors with
expression status was identified, confirming that
factors are direct transcriptional targets of ERG. Inhibition of ERG in
-positive VCaP cells led to decreased levels of NOTCH1 and 2 proteins and downstream transcriptional targets and partially recapitulated the phenotypes associated with ERG inhibition. Regulation of
and
genes by ERG were also noted with ectopic ERG expression in LNCaP (ERG-negative prostate cancer) and RWPE-1 (benign prostate-derived immortalized) cells. Furthermore, inhibition of NOTCH by the small-molecule γ-secretase inhibitor 1, GSI-1, conferred an increased sensitivity to androgen receptor (AR) inhibitors (bicalutamide and enzalutamide) or the androgen biosynthesis inhibitor (abiraterone) in VCaP cells. Combined treatment with bicalutamide and GSI-1 showed strongest inhibition of AR, ERG, NOTCH1, NOTCH2, and PSA protein levels along with decreased cell growth, cell survival, and enhanced apoptosis. Intriguingly, this effect was not observed in ERG-negative prostate cancer cells or immortalized benign/normal prostate epithelial cells. These data underscore the synergy of AR and NOTCH inhibitors in reducing the growth of ERG-positive prostate cancer cells.
Combinational targeting of NOTCH and AR signaling has therapeutic potential in advanced ERG-driven prostate cancers.
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Background: Dysfuncitons of androgen and TGF-β signaling play important roles in prostate tumorigenesis. PMEPA1 gene has been defined as an androgen and TGF-β responsive gene ...which inhibits androgen and TGF-β signaling via negative feed-back loops. Our previous data has established that PMEPA1 distinct isoforms ( PMEPA1-a and PMEPA1-b) with disparities within N-terminus protein sequences navigate different androgen/TGF-β signaling regulations. In this study, the roles of PMEPA1 isoforms in disease progressions were investigated in solid tumors of prostate (CaP), breast, lung and colon. Methods: RNA seq data from total 2479 solid tumor samples in the TCGA dataset were used to study the correlation between expressions of PMEPA1 isoforms and disease progression including Gleason score, pathology stages, progression free survival rate (PFS) and overall survival rate (OS). The cohort is composed of 482 prostate, 1049 breast, 499 lung and 449 colon cancer patients. Results: In CaP, the TCGA data analysis showed that lower transcript level of PMEPA1-b isoform associated with higher Gleason scores and lower progression free survival rate (PFS) (P = 0.014) and worse overall survival rate (OS) (P < 0.01). The ratio of mRNA levels of PMEPA1-a versus PMEPA-b indicated higher Gleason score, lower PFS rate (P = 0.0063) and worse OS rate (P = 0.0042). In contrast, higher expression of both PMEPA1-a and PMEPA- b associated with lower PFS (P = 0.023 and 0.028, respectively) in breast cancer. And the enhanced ratio of PMEPA1-a/ b was also found to indicate lower PFS (P = 0.016) and worse OS (P = 0.016) in breast cancer. Similarly, the increased transcript levels of PMEPA1-a and PMEPA1-b isoforms significantly associated with lower PFS and worse OS rates in lung and colon cancer. The expression of PMEPA1 isoforms was not found to associate with pathology stages of diseases. Conclusions: Our data establish the biomarker potential of PMEPA1 gene isoforms ( a and b) indicating more aggressive disease progressions in 4 solid tumors, further underscoring the PMEPA1 isoform specific biological functions to differentiate regulation of androgen and TGF-β signaling in cancer cells.
Background: Poly ADP-ribose polymerase inhibitors (PARPis) are an important class of therapeutics for metastatic castration-resistant prostate cancer (mCRPC). Unlike hormone-based treatments for ...mCRPC, PARPis are not without drug-related hematological adverse events. Objective: To review the evidence on hematological toxicities, including anemia, thrombocytopenia, and neutropenia from PARPis in prostate cancer. Study Methodology: A systematic review and meta-analysis using the PRISMA guidelines was performed for phase II and III randomized controlled trials (RCTs) of PARPis in prostate cancer. PubMed, Embase, and Ovid All EBM reviews—Cochrane were queried from inception to 9 June 2023. The Mantel–Haenszel method was used to report risk ratios (RR) and 95% confidence intervals (CI) for all-grade and high-grade anemia, thrombocytopenia, and neutropenia toxicities. Results: The systematic review retrieved eight phase II and III RCTs; specifically, eight were included in the anemia, five in the all-grade thrombocytopenia and neutropenia, and four in the high-grade thrombocytopenia and neutropenia outcomes. Compared to a placebo and/or other non-PARPi treatments, PARPi use was associated with an increased risk of all-grade anemia (RR, 3.37; 95% CI, 2.37–4.79; p < 0.00001), thrombocytopenia (RR, 4.54; 95% CI, 1.97–10.44; p = 0.0004), and neutropenia (RR, 3.11; 95% CI, 1.60–6.03; p = 0.0008). High-grade anemia (RR, 6.94; 95% CI, 4.06–11.86; p < 0.00001) and thrombocytopenia (RR, 5.52; 95% CI, 2.80–10.88; p < 0.00001) were also associated with an increased risk, while high-grade neutropenia (RR, 3.63; 95% CI, 0.77–17.23; p = 0.10) showed no significant association. Subgroup stratification analyses showed differences in various all-grade and high-grade toxicities. Conclusion: PARPis were associated with an increased risk of hematological AEs. Future studies with more pooled RCTs will enhance this understanding and continue to inform patient–physician shared decision-making. Future studies may also have a role in improving the current management strategies for these AEs.
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