Characterization of T cell receptor repertoire in penile cancer.

Tumor-infiltrating lymphocytes (TILs) play a key role in regulating the host immune response and shaping tumor microenvironment. It has been previously shown that T cell infiltration in penile tumors was associated with clinical outcomes. However, few studies have reported the T cell receptor (TCR) repertoire in patients with penile cancer. In the present study, we evaluated the TCR repertoires in tumor and adjacent normal tissues from 22 patients with penile squamous cell carcinoma (PSCC). Analysis of the T cell receptor beta-variable (TRBV) and joining (TRBJ) genes usage and analysis of complementarity determining region 3 (CDR3) length distribution did not show significant differences between tumor and matched normal tissues. Moreover, analysis of the median Jaccard index indicated a limited overlap of TCR repertoire between these groups. Compared with normal tissues, a significantly lower diversity and higher clonality of TCR repertoire was observed in tumor samples, which was associated with clinical characteristics. Further analysis of transcriptional profiles demonstrated that tumor samples with high clonality showed increased expression of genes associated with CD8 + T cells. In addition, we analyzed the TCR repertoire of CD4 + T cells and CD8 + T cells isolated from tumor tissues. We identified that expanded clonotypes were predominantly in the CD8 + T cell compartment, which presented with an exhausted phenotype. Overall, we comprehensively compared TCR repertoire between penile tumor and normal tissues and demonstrated the presence of distinct T cell immune microenvironments in patients with PSCC.

BIRC5 regulates inflammatory tumor microenvironment-induced aggravation of penile cancer development in vitro and in vivo.

BACKGROUND: Baculoviral IAP repeat containing 5 (BIRC5) is overexpressed and plays as a key regulator in the progression of various human carcinomas. The inflammatory tumor microenvironment (ITM) is closely associated with the development of cancers. However, the role of BIRC5 in penile cancer (PC) and the ITM-induced abnormal progression of PC is still obscure. METHODS: In this study, serum and tissues of patients with PC were recruited to evaluate the expression profile of BIRC5. We used PC cell lines (Penl1 and Penl2) and constructed a PC xenograft mice model to explore the effects of the silencing of BIRC5 on proliferation, migration, invasion and tumor growth, as well as survival of mice. Besides, interferon (IFN)-γ was utilized to mimic the ITM of PC cells. RESULTS: Our results showed that BIRC5 was dramatically upregulated in the serum and tissues of PC patients, as well as PC cell lines. Knockdown of BIRC5 inhibited the proliferation, migration and invasion of PC cells. Meanwhile, it suppressed PC xenograft tumor growth and improved mice survival. Moreover, IFN-γ significantly aggravated PC progression both in vivo and in vitro while the silencing of BIRC5 reversed these unfavorable effects. CONCLUSIONS: Taken together, our data revealed that BIRC5 silencing inhibited aggravation of PC cell processes and tumor development induced by ITM. This suggested that BIRC5 may function as a diagnosis and therapy target of PC in the future.

Investigation of the Epithelial to Mesenchymal Transition (EMT) Process in Equine Papillomavirus-2 (EcPV-2)-Positive Penile Squamous Cell Carcinomas.

Equine penile squamous cell carcinoma (epSCC) is the most frequent tumor of the external male genitalia, representing 67.5% of equine genital cancers. epSCC is associated with papilloma virus (PV) infection and has been recently proposed as a model for human PV-induced squamous cell carcinomas. It has already been suggested that epSCC might undergo epithelial-to-mesenchymal transition (EMT). This work aims to investigate in detail this process and the possible role of PV oncoproteins in epSCC. For this purpose, 18 penile SCCs were retrospectively selected and tested for both EcPV2 presence and oncoproteins (EcPV2 E6 and EcPV2 E7) expression. Moreover, immunohistochemical EMT characterization was carried out by analyzing the main epithelial markers (E-cadherin, ß-catenin, and pan-cytokeratin AE3/AE1), the main mesenchymal markers (N-cadherin and vimentin), and the main EMT-related transcription factors (TWIST-1, ZEB-1). PCR analysis was positive for EcPV2 in 16 out of 18 samples. EMT was investigated in epSCC positive for EcPV2. The immunohistochemistry results suggested the presence of EMT processes in the neoplastic cells at the tumor invasive front. Moreover, the significant upregulation of RANKL, together with BCATN1, LEF1, and FOSL1 genes, might suggest a canonical Wnt pathway activation, similarly to what is reported in human penile squamous cell carcinomas.

Molecular stratification by BCL2A1 and AIM2 provides additional prognostic value in penile squamous cell carcinoma.

Background: Lymph node metastasis is the most unfavorable prognostic factor of penile squamous cell carcinoma (PSCC). However, patients with the same lymph node status have different outcomes, and molecular classifiers for precise prognostic assessments are lacking. Methods: Comprehensive genomic profiling and high-content proliferation screening were performed in eight PSCC and normal tissue pairs and in cell lines. BCL2A1 and AIM2 were selected and further evaluated by qPCR and Western blot. The clinical relevance and prognostic value of the target genes were validated via immunohistochemistry in a cohort of 220 PSCC patients with a defined pN stage. Finally, the biological functions and molecular mechanisms of BCL2A1 and AIM2 were investigated in vitro and in vivo. Results: BCL2A1 and AIM2 were both upregulated in PSCC tissues and associated mostly with cell proliferation. Staining for either BCL2A1 or AIM2 revealed that both are correlated with pN status, extranodal extension, clinical stage and cancer-specific survival (CSS). Compared to patients who are single-positive or double-negative for BCL2A1 and AIM2, those overexpressing both genes had a higher risk of tumor progression and the poorest survival in the pN0 (5-year CSS: 63.3% vs. 94.9% and 100.0%, respectively, p = 0.000) and pN+ subsets (5-year CSS: 24.1% vs. 45.7% and 55.1%, respectively, p = 0.035). Molecular biofunction and mechanistic studies demonstrated that BCL2A1 and AIM2 knockdown inhibited tumorigenesis via the AIM2/NF-κB/BCL2A1/MAPK/c-Myc signaling pathway. Conclusions: BCL2A1 and AIM2 promote PSCC progression. Integrating BCL2A1 and AIM2 as novel molecular classifiers with pN stage provides additional information for the prognosis and treatment of PSCC patients.

The HPV and p63 Status in Penile Cancer Are Linked with the Infiltration and Therapeutic Availability of Neutrophils.

Squamous penile cancer displays a rare human papillomavirus (HPV)-associated tumor entity. Investigations on the molecular pathogenesis of HPV-driven penile cancer are impaired by the rareness of clinical specimens and, in particular, are missing relevant cell culture models. Here, we identified in HPV-positive penile cancer cell lines that HPV16 oncoproteins control TP63 expression by modulating critical regulators, while integration into the TP63 open reading frame facilitates oncogene expression. The resulting feed-forward loop leads to elevated p63 levels that in turn enhance the release of the neutrophil-recruiting chemokine CXCL8. Remarkably, elevated CXCL8 amounts lead to the increased surface exposition of the Fc receptor of human IgA antibodies, FcαRI, on neutrophils and correlated with a higher susceptibility to antibody-dependent neutrophil-mediated cytotoxicity (ADCC) using an EGFR-specific IgA2 antibody. IHC staining of tissue microarrays proved that elevated expression of p63 together with neutrophil infiltration were significantly more frequent in HPV-positive penile cancer displaying a higher tumor grade. In summary, we identified a promising marker profile of patients with penile cancer at higher risk for worse prognosis. However, these patients may benefit from immunotherapeutic approaches efficiently engaging neutrophils for tumor cell killing.

Effective combinatorial immunotherapy for penile squamous cell carcinoma.

Penile squamous cell carcinoma (PSCC) accounts for over 95% of penile malignancies and causes significant mortality and morbidity in developing countries. Molecular mechanisms and therapies of PSCC are understudied, owing to scarcity of laboratory models. Herein, we describe a genetically engineered mouse model of PSCC, by co-deletion of Smad4 and Apc in the androgen-responsive epithelium of the penis. Mouse PSCC fosters an immunosuppressive microenvironment with myeloid-derived suppressor cells (MDSCs) as a dominant population. Preclinical trials in the model demonstrate synergistic efficacy of immune checkpoint blockade with the MDSC-diminishing drugs cabozantinib or celecoxib. A critical clinical problem of PSCC is chemoresistance to cisplatin, which is induced by Pten deficiency on the backdrop of Smad4/Apc co-deletion. Drug screen studies informed by targeted proteomics identify a few potential therapeutic strategies for PSCC. Our studies have established what we believe to be essential resources for studying PSCC biology and developing therapeutic strategies.

Report From the International Society of Urological Pathology (ISUP) Consultation Conference on Molecular Pathology of Urogenital Cancers V: Recommendations on the Use of Immunohistochemical and Molecular Biomarkers in Penile Cancer.

Penile cancer and its precursor lesions are morphologically and clinically heterogenous and they can be further characterized by immunohistochemical (IHC) and molecular genetic analyses. According to the current World Health Organization (WHO) classification, penile intraepithelial neoplasia (PeIN) and invasive penile carcinomas can be grouped into human papillomavirus (HPV)-related and non-HPV-related neoplasms. This distinction is clinically relevant for etiological and prognostic reasons. To gain insight into the current use of molecular testing and IHC in their diagnostics, a survey was held among the membership of the International Society of Urological Pathology (ISUP). About 250 pathologists from 51 countries answered the survey on the practice and use of IHC/molecular technique as aids in the diagnosis of penile squamous neoplasia. More than half (60%) of the respondents worked at an academic hospital. The questions focused on condylomas, precancerous squamous lesions, and squamous cell carcinoma (SCC). About 35% to 45% of the pathologists considered the use of IHC or molecular tests of value in the pathologic evaluation of precancerous and invasive neoplasms. The vast majority of the respondents do not use IHC for the diagnosis and subtyping of condylomas. There is emerging evidence that some condylomas may participate in the penile carcinogenesis process, especially the high-risk HPV-related atypical condylomas. We recommend the use of p16 in such cases. For most PeIN cases, about half of the responding pathologists make the diagnosis on hematoxylin and eosin slides only. For their subtyping, 50% to 55% of the pathologists use IHC in warty or basaloid PeINs and 40% in differentiated PeIN. To separate HPV-related PeIN from non-HPV-related PeIN, 80% reported using p16 and 20% Ki-67. On the basis of literature review and our practice, the ISUP working group recommends the use of Ki-67 to separate non-HPV-differentiated PeIN from squamous hyperplasia and the use of p16 to distinguish the pleomorphic variant of differentiated PeIN from HPV-related PeIN. With respect to SCCs, according to the survey, immunostaining is only applied in 15% of conventional invasive SCCs, the majority being diagnosed by hematoxylin and eosin. To separate HPV and non-HPV tumors, most (80%) would use p16 and 25% would use p53. For subtype classification, they consider IHC necessary to identify verrucous, papillary, warty, warty-basaloid, and basaloid carcinomas. p16 is used as a surrogate of polymerase chain reaction for the identification of high-risk HPV. We recommend the use of p16 immunostain in cases where the tumoral histologic features of the SCCs are not classical for HPV-related neoplasms, especially in poorly differentiated tumors. Because the majority of these neoplasms harbor high-risk HPV (HPV16), identifying the presence of the virus is rather more important than documenting its specific genotype.

Solitary Penile Metastasis of Prostate Cancer on 18F-Fluciclovine PET/CT Imaging in a Patient With PSA of 1 ng/mL.

An 85-year-old asymptomatic man with suspected biochemical recurrence of prostate cancer underwent an F-fluciclovine PET/CT scan, which revealed a solitary suspicious tracer uptake in the dorsal right corporal body of the proximal pendulous penis. The patient underwent ultrasound-guided fine-needle aspiration of the penile lesion, which revealed metastatic prostate cancer. The patient had definitive external beam radiation therapy 3 years before the examination. At the time of scan, the prostatic-specific antigen (PSA) was only 1.0 ng/mL, although the PSA doubling time was 2.6 months. It is unusual to detect a solitary penile metastasis in a patient with a low level of PSA.

Up-regulation of indoleamine 2,3-dioxygenase 1 (IDO1) expression and catalytic activity is associated with immunosuppression and poor prognosis in penile squamous cell carcinoma patients.

BACKGROUND: Indoleamine 2,3-dioxygenase 1 (IDO1) and tryptophan (Trp) catabolism have been demonstrated to play an important role in tumor immunosuppression. This study examined the expression and catalytic activity of IDO1 in penile squamous cell carcinoma (PSCC) and explored their clinical significance. METHODS: IDO1 expression level, serum concentrations of Trp and kynurenine (Kyn) were examined in 114 PSCC patients by immunohistonchemistry and solid-phase extraction-liquid chromatography-tandem mass spectrometry. The survival was analyzed using Kaplan-Meier method and the log-rank test. Hazard ratio of death was analyzed via univariate and multivariate Cox regression. Immune cell types were defined by principal component analysis. The correlativity was assessed by Pearson's correlation analysis. RESULTS: The expression level of IDO1 in PSCC cells was positively correlated with serum Kyn concentration and Kyn/Trp radio (KTR; both P < 0.001) but negatively correlated with serum Trp concentration (P = 0.001). Additionally, IDO1 up-regulation in cancer cells and the increase of serum KTR were significantly associated with advanced N stage (both P < 0.001) and high pathologic grade (P = 0.008 and 0.032, respectively). High expression level of IDO1 in cancer cells and serum KTR were associated with short disease-specific survival (both P < 0.001). However, besides N stage (hazard radio [HR], 6.926; 95% confidence interval [CI], 2.458-19.068; P < 0.001) and pathologic grade (HR, 2.194; 95% CI, 1.021-4.529; P = 0.038), only serum KTR (HR, 2.780; 95% CI, 1.066-7.215; P = 0.036) was an independent predictor for PSCC prognosis. IDO1 expression was positively correlated with the expression of interferon-γ (IFNγ, P < 0.001) and immunosuppressive markers (programmed cell death protein 1, cytotoxic T-lymphocyte-associated protein 4 and programmed death-ligand 1 and 2; all P < 0.05), and the infiltration of immune cells (including cytotoxic T lymphocytes, regulatory T lymphocytes, tumor-associated macrophages, and myeloid-derived suppressor cells; all P < 0.001) in PSCC tissues. Furthermore, the expression of IDO1 was induced by IFNγ in a dose-dependent manner in PSCC cells. CONCLUSIONS: IFNγ-induced IDO1 plays a crucial role in immunoediting and immunosuppression in PSCC. Additionally, serum KTR, an indicator of IDO1 catabolic activity, can be utilized as an independent prognostic factor for PSCC.

PD-L1 and p16 Expression in Penile Squamous Cell Carcinoma From an Endemic Region.

BACKGROUND: Penile squamous cell carcinoma (PSCC) is a rare malignancy with higher incidence in developing countries. Treatment options include surgery, radiation therapy, and systemic chemotherapy. However, effective treatments for advanced disease are lacking. To understand the biology underlying PSCC may help the development of new therapeutic strategies. The objective of this study was to evaluate immunohistochemical expression of programmed death-ligand 1 (PD-L1) and p16 in PSCC and its association with clinicopathologic features and outcomes. PATIENTS AND METHODS: A cohort of 40 patients with PSCC from an academic institution in Brazil was analyzed. Clinicopathologic features and outcomes were retrospectively collected. PD-L1 and p16 immunohistochemical expression were performed in formalin-fixed paraffin-embedded specimens. PD-L1 was positive with any staining in more than 1% of tumor, and p16 was positive in more than 10%. Associations were performed using the Mann-Whitney and Fisher exact test. Kaplan-Meier curves were used to estimate survival rates with log-rank. RESULTS: Of 35 patients, 5 were excluded, 4 owing to a lack of data and 1 owing to no tumor available; 18 (51.4%) patients were PD-L1-positive (PD-L1+). PD-L1+ was associated with larger tumors (P = .027). There was an association between PD-L1+ and p16 expression (P = .002). PD-L1+ was more frequent in grade II and III disease than grade I (77.8% vs. 22.2%) and was expressed in all patients with grade III disease. Lymph node involvement was associated with PD-L1 expression (69.2% PD-L1+ vs. 30.8% PD-L1-negative). The 5-year mortality was 37.1%. CONCLUSION: PD-L1 expression appears to be associated with p16 expression, larger tumors, and worse clinical outcomes in PSCC and may provide clinical data for new studies to evaluate anti-PD-L1 immune therapies.

MIR-107, MIR-223-3P and MIR-21-5P Reveals Potential Biomarkers in Penile Cancer.

BACKGROUND: Inguinal lymph node involvement is the main prognostic factor in patients with penile cancer. However, there is a lack of marker/s for lymph node metastasis. microRNAs have been investigated as potential markers for prognosis of various types of cancer. Taking this into consideration, our main goal was to determine the association of miR-223-3p, miR-107, and miR-21-5p expression with clinicopathological characteristics, as well as presence of lymph node metastasis in patients with penile cancer. METHODS: Formalin-fixed paraffin-embedded penile squamous cell carcinoma specimens from 50 patients, at diagnosis and prior to any cancer treatment, were obtained. Tissue samples comprising at least 70% malignant cells and adjacent non-tumor tissues were evaluated by using qRT-PCR for expression level of miR-223-3p, miR-107 and miR-21-5p. Additionally, molecular identification of HPV was performed by PCR, and the expression levels of PTEN were analyzed by immunohistochemistry. RESULTS: Penile squamous cell carcinoma primary tumors presented higher expression of miR-223-3p, miR-107, and miR-21-5p when compared to non-tumor adjacent tissues. Upregulation of miR-223-3p was associated lymph node metastasis. Higher expression of miR-107 was associated with worsening of prognosis (as observed by histological grade II and III, tumors bigger than 2.0 cm, stage III and IV, and lower disease-free survival). In addition, higher expression of miR-107 and miR-21-5p was correlated to the absence of PTEN protein expression. CONCLUSIONS: Our data demonstrate that higher expression of miR-223-3p, miR-107, and miR-21-5p is correlated with poor prognosis in penile cancer. The upregulation of these microRNAs potentially affect critical cancer pathways and may be important for the prognosis and response to therapy in penile cancer.

An update on systemic therapy for penile cancer.

PURPOSE OF REVIEW: Whereas substantial advances have been made in systemic tumour therapy in the past decade, the prognosis of advanced squamous cell carcinoma (SCC) of the penis remains disproportionally poor. In this review, we aimed to present an update on systemic therapy of penile SCC highlighting the most recent data and future perspectives. RECENT FINDINGS: Lymph node metastases play a key role in treating and assessing the prognosis of patients with penile SCC. Data show longer overall survival with the use of adjuvant chemotherapy in patients with pelvic lymph node metastases and recent analyses lead to the development of a nomogramm predicting overall survival in connection with the use of perioperative chemotherapy. There are two pathways in the pathogenesis of penile cancer, including human papilloma virus related and unrelated, leading to many possible novel therapeutic targets. Other targeted therapies have been evaluated, which show promising results with the use of tyrosine kinase inhibitors. SUMMARY: Chemotherapy has shown moderate activity in advanced stages of the disease, however, the ideal timing of chemotherapy in patients with lymph node metastases is not entirely clear. Potential targets for future therapies exist, and are already being tested in other malignancies. Owing to the rarity of this condition, a robust evidence is lacking and it is of great importance to pursue further research to unveil several aspects of this disease, particularly in patients with recurrence, lymph node metastases or metastatic disease.

Expression of LHCG receptors in the human penis.

The aim of this study is to investigate the expression of the luteinizing hormone/choriogonadotropin (LHCG) receptor in the human penis to see, if the luteinizing hormone (LH) effects are possible in the spongious and cavernous tissue of the penis. The number of men with erection disturbances increases significantly simultaneously with the elevated LH concentrations between 40 and 70 years. It is possible that the elevated LH concentrations may influence locally the erectile mechanisms. The precondition for this is the expression of LHCG receptors in the penis. Penile tissue was obtained from three patients undergoing total or partial penectomy due to a rectal cancer with secondary penile metastasis or squamous cell carcinoma of the penis. Immunohistochemistry was used for the detection of the LHCG receptor. Positive immunoreaction for LHCG receptors was discovered in the endothelial cells of cavernous spaces in the corpus cavernosum and corpus spongiosum penis, also in the endothelial cells of the capillary walls in all patients. Our results show that LHCG receptor is expressed in the spongious and cavernous tissue of the human penis. This finding suggests that LH can affect the spongious and cavernous tissue in human and play a significant role in the development of erectile dysfunction among the aging men.

PD-L1 Expression in Men with Penile Cancer and its Association with Clinical Outcomes.

BACKGROUND: It has been hypothesized that PD-L1 expression in tumor cells and tumor-infiltrating immune (TII) cells may contribute to tumor progression by inhibiting antitumor immunity. OBJECTIVE: To investigate the association between PD-L1 expression in tumor cells and TII cells and clinical outcomes in penile cancer. DESIGN, SETTING, AND PARTICIPANTS: A cohort of 222 men treated for penile squamous cell carcinoma (SqCC) at Örebro University Hospital between 1984 and 2008 with long-term follow-up (median 34 mo) was evaluated for PD-L1 expression in tumor cells and TII cells via immunohistochemistry. OUTCOME MEASUREMENTS AND STATISTICAL ANALYSIS: Association between clinicopathological features and PD-L1 expression was estimated using χ2 and Fisher's exact tests. For survival analyses, Kaplan-Meier curves with log-rank tests and multivariate Cox proportional hazards regression models were used. RESULTS AND LIMITATIONS: We found that 32.1% of the tumors and 64.2% of the TII cells expressed PD-L1. Our data demonstrate that penile SqCC patients with PD-L1-positive tumor cells or TII cells are at significant risk of lower cancer-specific survival and that the prognostic value of PD-L1 expression was strongest for tumor cell positivity. The use of tissue microarrays rather than whole sections may be viewed as a limitation. CONCLUSIONS: Tumor PD-L1 expression independently identifies penile SqCC patients at risk of poor clinical outcomes. PATIENT SUMMARY: We investigated how many patients with penile cancer had tumors that manufactured PD-L1, a protein that decreases the ability of the immune system to fight cancer. We found that up to one-third of penile tumors make this protein. Patients whose tumors make PD-L1 have more aggressive penile cancer and worse clinical outcomes.

Impact of PI3K-AKT-mTOR Signaling Pathway Up-regulation on Prognosis of Penile Squamous-Cell Carcinoma: Results From a Tissue Microarray Study and Review of the Literature.

PURPOSE: To assess the prognostic value of PI3K-AKT-mTOR signaling pathway up-regulation in a contemporary cohort of penile squamous-cell carcinoma (PSCC) patients. PATIENTS AND METHODS: Tissue microarrays were constructed for 57 patients with invasive PSCC treated at our institution between 2000 and 2013. Immunohistochemical staining was performed for PTEN, AKT, and S6. Human papillomavirus (HPV) in-situ hybridization for high-risk subtypes was also performed. Biomarker expression was evaluated by a semiquantitative H score. Overall survival, disease-specific survival and recurrence-free survival stratified by biomarker expression (low vs. high) were estimated by the Kaplan-Meier method. Multivariable Cox regression models were used to determine predictors of mortality and recurrence. RESULTS: HPV in-situ hybridization was positive in 23 patients (40%). PTEN was down-regulated in 43 patients (75%), while phosphorylated-AKT (p-AKT) and phosphorylated-S6 (p-S6) were up-regulated in 27 (47%) and 12 patients (21%), respectively. In multivariable Cox regression models, patients with low expression of p-AKT had an increased risk of recurrence (hazard ratio [HR] = 3.95; 95% confidence interval [CI], 1.47-10.59; P = .02), while those with low expression of p-S6 had an increased risk of overall mortality (HR = 6.15; 95% CI, 1.55-24.36; P = .01). HPV status was an independent predictor of overall survival (HR = 6.99; 95% CI, 2.42-20.16; P < .001) and disease-specific survival (HR = 6.74; 95% CI, 2.02-22.48; P = .002). CONCLUSION: PI3K-AKT-mTOR signaling pathway up-regulation and HPV coinfection in PSCC are associated with favorable disease. mTOR pathway biomarkers along with HPV status may represent novel prognosticators for risk stratification of PSCC patients and may help guide treatment decisions and follow-up strategies. These findings require further investigation.

Molecular carcinogenesis in equine penile cancer: A potential animal model for human penile cancer.

OBJECTIVES: To evaluate the expression of COX-2, E-cadherin, vimentin, 14-3-3σ, and Phosphatase and tensin homolog (PTEN) tumor-related proteins in equine penile papillomas (ePP) and squamous cell carcinomas (ePSCC), the occurrence of epithelial-mesenchymal transition (EMT) at the invasion front (IF) and compare our findings with current knowledge on human penile squamous cell carcinoma (hPSCC). MATERIAL AND METHODS: We analyzed, by immunohistochemistry in 45 equine penile proliferative epithelial lesions, the expression of COX-2, E-cadherin, vimentin, 14-3-3σ, and PTEN using monoclonal antibodies. Tumors were histopathologically classified as well-differentiated or poorly differentiated using the IF grading scheme. Semiquantitative analysis was performed to determine down or up-regulation of the proteins and association with histopathological characteristics were statistically investigated using Mann-Whitney U test and/or Spearman's tests. RESULTS: COX-2 was neo-expressed in 86.6% of the cases and expression progressively increased from ePP to ePSCC (P = 0.0003) and from well to poorly differentiated (P = 0.033). High COX-2 expression was associated with a high mitotic index (MI) (P = 0.026). In contrast to normal epidermis, ePSCC had very low E-cadherin expression in 64% of the cases (P = 0.0005). Vimentin was neo-expressed in 65% of poorly differentiated ePSCC at the IF indicating EMT. Cytoplasmic 14-3-3σ protein expression was reduced in 42% of the ePSCC and additionally, nuclear expression of 14-3-3σ in neoplastic keratinocytes and in the cytoplasm of stromal fibroblasts at the IF was features only found in ePSCC. PTEN protein showed a tendency to be decreased or lost in ePSCC. CONCLUSIONS: Our study provides evidence of molecular abnormalities in ePSCC similar to those reported for human PSCC. The occurrence of EMT at the IF is a common event in ePSCC. Naturally occurring ePSCC could serve as a valuable preclinical animal model to explore upcoming therapeutic options for hPSCC.

Prognostic Significance of P16INK4a Expression in Penile Squamous Cell Carcinoma: A Meta-Analysis with Trial Sequential Analysis.

BACKGROUND: Recently, P16INK4a expression has been shown to be correlated with cancer-specific survival (CSS) in penile squamous cell carcinoma (SCC). Therefore, we performed this meta-analysis to clarify the prognostic value of P16INK4a for penile SCC. METHODS: A systematic search was performed in PubMed, Embase, and Web of Science to identify all relevant articles up to May 25, 2017. Hazard ratios (HRs) and corresponding 95% confidence intervals (CIs) of included studies were pooled to estimate the prognostic value. Trial sequential analysis (TSA) was performed to assess the quantity and strength of survival evidence. RESULTS: Five retrospective studies consisting of 323 cases were finally included. We found that P16INK4a positive expression was significantly associated with a better CSS of penile SCC (HR=0.45, 95%CI: 0.30-0.67, P<0.001). No heterogeneity or publication bias was noted among the included studies. Furthermore, TSA demonstrated that the findings were based on sufficient evidence. CONCLUSIONS: P16INK4a positive expression is independently associated with improved CSS for patients with penile SCC.

Nuclear loss and cytoplasmic expression of androgen receptor in penile carcinomas: role as a driver event and as a prognosis factor.

Androgen receptor (AR) is a member of the steroid and nuclear family receptor that acts as transcription factor. AR signaling plays pivotal role in the development and progression of prostate cancer. However, the role of AR in penile cancer (PeCa) is poorly explored. Our previous molecular studies unveiled frequent AR mRNA loss in PeCa, which was further predicted as a major driver alteration in this neoplasm. Herein, we assessed the AR protein expression in 59 usual PeCa tissues and 42 surrounding normal tissues (SNT) by immunohistochemistry using a tissue microarray. In a paired analysis, we found a total absence of nuclear AR expression in PeCa while 95.2% of SNT samples presented strong nuclear AR expression (P < 0.001). Interestingly, 17 of 42 PeCa presented weak or moderate cytoplasmic AR staining, contrasting with 5 of 42 SNT (P = 0.008). Increased levels of AR cytoplasmic expression were related with poor prognosis features including advanced clinical staging (P = 0.044), compromised surgical margins (P = 0.005), and pathological inguinal node status (P = 0.047). Furthermore, AR cytoplasmic expression was also related with shorter overall survival (P = 0.032). In conclusion, the frequent loss of nuclear AR protein levels suggests a potential function in PeCa development. Based on this result, the androgen deprivation therapy is not indicated for PeCa patients. In addition, the AR cytoplasmic expression found in a significant number of cases (40.5%) showed prognostic value and pathways activated by the non-genomic AR signaling may represent a promising therapeutic strategy.

Prognostic Significance of HPV and p16 Status in Men Diagnosed with Penile Cancer: A Systematic Review and Meta-analysis.

It has been shown that human papillomavirus (HPV) and p16 status has prognostic value in some HPV-associated cancers. However, studies examining survival in men with penile cancer according to HPV or p16 status are often inconclusive, mainly because of small study populations. The aim of this systematic review and meta-analysis was to examine the association between HPV DNA and p16 status and survival in men diagnosed with penile cancer. Multiple electronic databases were searched. Twenty studies were ultimately included and study-specific and pooled HRs of overall survival and disease-specific survival (DSS) were calculated using a fixed effects model. In the analysis of DSS, we included 649 men with penile cancer tested for HPV (27% were HPV-positive) and 404 men tested for p16 expression (47% were p16-positive). The pooled HRHPV of DSS was 0.61 [95% confidence interval (CI), 0.38-0.98], and the pooled HRp16 of DSS was 0.45 (95% CI, 0.30-0.69). In conclusion, men with HPV or p16-positive penile cancer have a significantly more favorable DSS compared with men with HPV or p16-negative penile cancer. These findings point to the possible clinical value of HPV and p16 testing when planning the most optimal management and follow-up strategy. Cancer Epidemiol Biomarkers Prev; 27(10); 1123-32. ©2018 AACR.