Genetic imbalances in 26 cases of penile squamous cell carcinoma

High TRIAP1 expression in penile carcinoma is associated with high risk of recurrence and poor survival

Background

TP53-regulated inhibitor of apoptosis 1 (TRIAP1), also known as p53 cell survival factor or p53CSV, is reported to be associated with resistance of apoptosis in different human malignancies, but the potential role of TRIAP1 in penile carcinoma (PeCa) has not been well studied. This study aimed to analyze the association between TRIAP1 expression and clinical outcome in PeCa patients.

Methods

Bioinformatics was used to analyze the differential TRIAP1 expression in PeCa compared with normal tissues in Gene Expression Omnibus (GEO) Dataset (GSE57955). The expression of TRIAP1 in tumor specimens from 57 patients undergoing radical penile surgery was detected by immunohistochemistry (IHC). Differential TRIAP1 expression in various human malignancies was also assessed by GEPIA web-tool based on The Cancer Genome Atlas (TCGA) Datasets. Subsequently, the relationship between TRIAP1 expression and clinical prognosis of PeCa patients was analyzed.

Results

Both IHC and GEO Dataset (GSE57955) showed that TRIAP1 was significantly overexpressed in PeCa tissues when compared with normal tissues. Based on patient data and IHC on clinical specimens, we found that strong intensity of TRIAP1 expression was significantly related with higher histological grade (P=0.049) and elevated local recurrence rate (P=0.023), suggesting TRIAP1 as a potential predictor in recurrence. Further, high TRIAP1 expression was identified to be a hazardous prognostic factor for local recurrence-free survival (RFS).

Conclusions

High TRIAP1 expression in PeCa is associated with high risk of recurrence and poor survival, suggesting TRIAP1 may become a potential prognostic factor for PeCa.

P53 Codon 72 Polymorphism and Risk for Squamous Cell Carcinoma of the Penis: A Caucasian Case-Control Study

Squamous cell carcinoma of the penis is a rare but often aggressive disease. A large proportion of penile cancers are associated with HPV infection, mainly with HPV high-risk subtypes 16 and 18. From other HPV-related malignancies a link between a functional SNP in the p53 gene (rs1042522, p.Arg72Pro) and a higher disease risk in the presence of HPV is documented. The p53 p.Arg72 variant was described as a risk factor for developing a malignancy in combination with the presence of HPV as the p.72Arg variant is more prone to HPV E6 protein-mediated degradation than the p.72Pro variant. For penile carcinoma there are only sparse data available on this topic. We therefore analyzed the distribution of this p53 codon 72 SNP in a cohort of 107 penile cancer patients and a healthy control group (n=194) using Restriction Fragment Length Polymorphism (RFLP) analysis. After DNA isolation a PCR amplicon including the variant nucleotide was generated. Based on the variant nucleotide this amplicon can be cleaved into two parts or remain unaffected by a restriction enzyme. Subsequent electrophoresis allowed the discrimination of SNP alleles in the investigated sample. Comparison of the allelic variants revealed no significant differences in the distribution of this SNP between cases and controls (p=0,622). There was also no difference in SNP distribution between cases with/without HPV infection (p=0,558) or histologic variants (p=0.339). In order to strengthen the impact of our data we performed a combined analysis of all published data on this topic with our results. This ended up in SNP distribution data from 177 cases and 1149 controls. Overall, there were also no significant differences in the allelic distribution of the p53 codon 72 SNP between either cases and controls (p=0,914) or HPV-positive and HPV-negative cases (p=0,486). From this most comprehensive data available to date we conclude that there is no influence of the p53 codon 72 SNP on the risk of development of penile carcinoma in Caucasians even in the presence of HPV.

Association between Human Papillomavirus and Non-cervical Genital Cancers in Brazil: A Systematic Review and Meta-Analysis

Background: Human papillomavirus (HPV) infection is associated with cervical cancer; however, it is controversial whether it is involved in non-cervical genital cancers. Objective: This study aimed to evaluate articles on the prevalence of HPV in penile cancer, vulvar cancer, colorectal cancer, prostate cancer and anal canal cancer in studies conducted in Brazil. Methods: The study was conducted in accordance with the Preferred Reporting of Systematic Reviews and Meta-Analysis Statement. Comprehensive searches for HPV and cancer for the years 2006 to 2016 were conducted in two databases (PubMed and Web of Knowledge) and Google Scholar system. We also tracked the references of all eligible articles to identify additional non-captured publications through online surveys. Results: Eighteen studies, with a combined sample size of 1,552 patients were analyzed. The overall prevalence of HPV was 43% (95% CI: 36–51%; p < 0.001). The pooled prevalence of HPV in penile cancer was 42% (95% CI: 32–55%; p < 0.001), in colorectal cancer it was 67% (95% CI: 64–70%; p < 0.001) and in vulvar cancer 43% (95% CI: 34–55%; p < 0.001). HPV 16 was the most prevalent in all sites evaluated, with prevalence estimated at 54% (95% CI: 44–66%; p < 0.001), followed by genotypes 33 (21%; 95% CI: 17–28; p < 0.001), 6 (15%; 95% CI: 8–26%; p < 0.001), 11 (13%; 95% CI: 5–32%; p < 0.001) and 18 (12%; 95% CI: 7–22%; p < 0.001), respectively. The pooled prevalence of single infection was 82% and infection by multiple genotypes of HPV was 22%. Conclusion: Our study demonstrated a high prevalence of HPV in non-cervical genital cancers in Brazil, with predominance of genotype 16, providing evidence for the need for preventive and control measures to avoid future harm to the population.

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.

The Emerging Role and Promise of Biomarkers in Penile Cancer

Penile cancer is a rare malignancy, which can be a source of devastating psychosexual distress because of its implication on sexual function and self-image. Current penile staging relies on invasive techniques and is often inaccurate. The authors review the promising biomarkers currently under investigation and their application to the staging and prognosis of penile cancer. Further development of such biomarkers provides the potential of improved clinical management of this disease.

DNA Copy Number Aberrations, and Human Papillomavirus Status in Penile Carcinoma. Clinico-Pathological Correlations and Potential Driver Genes

Penile squamous cell carcinoma is a rare disease, in which somatic genetic aberrations have yet to be characterized. We hypothesized that gene copy aberrations might correlate with human papillomavirus status and clinico-pathological features. We sought to determine the spectrum of gene copy number aberrations in a large series of PSCCs and to define their correlations with human papillomavirus, histopathological subtype, and tumor grade, stage and lymph node status. Seventy formalin-fixed, paraffin embedded penile squamous cell carcinomas were centrally reviewed by expert uropathologists. DNA was extracted from micro-dissected samples, subjected to PCR-based human papillomavirus assessment and genotyping (INNO-LiPA human papillomavirus Genotyping Extra Assay) and microarray-based comparative genomic hybridization using a 32K Bacterial Artificial Chromosome array platform. Sixty-four samples yielded interpretable results. Recurrent gains were observed in chromosomes 1p13.3-q44 (88%), 3p12.3-q29 (86%), 5p15.33-p11 (67%) and 8p12-q24.3 (84%). Amplifications of 5p15.33-p11 and 11p14.1-p12 were found in seven (11%) and four (6%) cases, respectively. Losses were observed in chromosomes 2q33-q37.3 (86%), 3p26.3-q11.1 (83%) and 11q12.2-q25 (81%). Although many losses and gains were similar throughout the cohort, there were small significant differences observed at specific loci, between human papillomavirus positive and negative tumors, between tumor types, and tumor grade and nodal status. These results demonstrate that despite the diversity of genetic aberrations in penile squamous cell carcinomas, there are significant correlations between the clinico-pathological data and the genetic changes that may play a role in disease natural history and progression and highlight potential driver genes, which may feature in molecular pathways for existing therapeutic agents.

Genomic profiling of human penile carcinoma predicts worse prognosis and survival

The molecular mechanisms underlying penile carcinoma are still poorly understood, and the detection of genetic markers would be of great benefit for these patients. In this study, we assessed the genomic profile aiming at identifying potential prognostic biomarkers in penile carcinoma. Globally, 46 penile carcinoma samples were considered to evaluate DNA copy-number alterations via array comparative genomic hybridization (aCGH) combined with human papillomavirus (HPV) genotyping. Specific genes were investigated by using qPCR, FISH, and RT-qPCR. Genomic alterations mapped at 3p and 8p were related to worse prognostic features, including advanced T and clinical stage, recurrence and death from the disease. Losses of 3p21.1-p14.3 and gains of 3q25.31-q29 were associated with reduced cancer-specific and disease-free survival. Genomic alterations detected for chromosome 3 (LAMP3, PPARG, TNFSF10 genes) and 8 (DLC1) were evaluated by qPCR. DLC1 and PPARG losses were associated with poor prognosis characteristics. Losses of DLC1 were an independent risk factor for recurrence on multivariate analysis. The gene-expression analysis showed downexpression of DLC1 and PPARG and overexpression of LAMP3 and TNFSF10 genes. Chromosome Y losses and MYC gene (8q24) gains were confirmed by FISH. HPV infection was detected in 34.8% of the samples, and 19 differential genomic regions were obtained related to viral status. At first time, we described recurrent copy-number alterations and its potential prognostic value in penile carcinomas. We also showed a specific genomic profile according to HPV infection, supporting the hypothesis that penile tumors present distinct etiologies according to virus status.

Molecular research in penile cancer-lessons learned from the past and bright horizons of the future?

Penile cancer is a rare tumor. There is a limited understanding of the biological mediators of prognostic and therapeutic importance in penile cancer. However, there exists some fundamental understanding of the major pathways involved in the development of penile pre-neoplastic lesions and neoplasms. The aim of the present review is to highlight our current state of molecular knowledge in penile cancer to foster the necessary tools for researchers to pave major advancements in our current treatment paradigms and cancer specific outcomes.

Chromosomal gains and losses in human papillomavirus-associated neoplasia of the lower genital tract - a systematic review and meta-analysis

BACKGROUND

Overexpression of the human papillomavirus (HPV) oncogenes E6 and E7 is necessary for the development of distinct lower genital tract cancers. However, secondary cellular genomic alterations are mandatory to promote progression of HPV-induced premalignant stages. We aimed at identifying the chromosomal regions most frequently gained and lost and the disease stage at which the latter occurs. These regions might be relevant for carcinogenesis and could serve as diagnostic markers to identify premalignant lesions with high progression risk towards invasive cancer.

METHODS

We performed a systematic literature review and meta-analysis of studies listed in PubMed that analysed chromosomal copy number alterations by comparative genomic hybridisation (CGH) in HPV-positive and -negative cancers or premalignant lesions of the anogenital tract (cervix, anus, vagina, penis and vulva).

FINDINGS

Data were extracted and analysed from 32 studies. The most common alterations in cervical squamous cell carcinoma (SCC) (12 studies, 293 samples) were gains at 3q with a rate of 0.55 (95% confidence interval (CI) 0.43-0.70), losses at 3p (0.36, 95%CI 0.27-0.48) and losses at 11q (0.33, 95%CI 0.26-0.43). Gains at 3q were particularly frequent in HPV16-positive cervical SCC (0.84, 95%CI 0.78-0.90). Also more than one quarter of high grade cervical intraepithelial neoplasia (CIN) harboured gains of 3q (0.27, 95%CI 0.20-0.36), but the rate in low grade CIN was low (0.02, 95%CI 0.00-0.09). For HPV-associated vulvar SCC (four studies, 30 samples) the same common alterations as in cervical SCC were reported. Studies on non-cervical and non-vulvar SCC and premalignant lesions of the lower genital tract are scarce.

INTERPRETATION

3q gains were most frequently found in HPV16-positive cervical SCC. The results suggest the selection of HPV-transformed cell clones harbouring 3q gains in high grade premalignant lesions, while alterations in low grade lesions are rare.

Prognostic factors and biomarkers of penile carcinoma

Penile squamous cell carcinoma (SCC) is a rare malignancy with highest incidence in underdeveloped and developing countries. Oncogenic human papilloma virus (HPV) DNA, mainly types 16 and 18, are found in ∼ 100% of patients with uterine cervix carcinoma. The incidence of this virus in SCC and its variations range from 30.5 to 80%. Despite controversies, contrary to the cervical carcinoma, in the carcinogenesis and disease progression of SCC, HPV-dependent and HPV-independent tumors need to be considered. Lymphadenectomies continue to be the gold standard treatment of lymph node metastases. Undesirable accuracy on staging system methods and high rates of lymphadenectomy complications are the principal objections to these surgical procedures; therefore, the main issue in patients with SCC is to know who should or should not undergo lymphadenectomy. The search for primary tumor anatomopathological and biomarker risk factors for lymph node metastases, such as has occurred in other tumors, may be an important tool to select lymphadenectomies candidates better. Histological subtypes, tumor grade, growth pattern, tumor thickness, lymphatic embolization by neoplasic cells and depth of infiltration have been reported as important prognostic factors for lymph node metastases. In our series, lymphatic vascular permeation, palpable lymph node after primary tumor control (cN stage), pattern of invasion, p53 and PCNA immunoreactivity are independent lymph node metastases risk factors in the multivariate model. It is strongly recommended that patients be concentrated in specialized centers or cancer hospitals and multi-centric prospective studies carried out on tumor markers in this rare disease, in order to stage better lymph node disease and avoid unnecessary surgeries with high morbidity rates.

Penile cancer: current therapy and future directions

Background Penile cancer (PC) is a rare cancer in western countries, but is more common in parts of the developing world. Due to its rarity and the consequent lack of randomized trials, current therapy is based on retrospective studies and small prospective trials. Design Studies of PC therapy were searched in PubMed and abstracts at major conferences. Results PC is generally an aggressive malignancy characterized by early locoregional lymph node (LN) spread and later metastases in distant sites. Given the strong predictive value of LN involvement for overall survival, evaluating regional LNs is critical. Advanced LN involvement is increasingly being treated with multimodality therapy incorporating chemotherapy and/or radiation. A single superior cisplatin-based regimen has not been defined. Further advances may occur with a better collaboration on an international scale and comprehensive understanding of tumor biology. To this end, the preventive role of circumcision and understanding of the oncogenic roles of Human Papilloma Virus-16, and smoking may yield advances. Preliminary data suggest a role for agents targeting epidermal growth factor receptor and angiogenesis. Conclusion Advances in therapy for PC will require efficient trial designs, synergistic collaboration, incentives to industry and the efforts of patient advocacy groups and venture philanthropists.

[Analysis of cytogenetic abnormalities in squamous cell carcinoma by array comparative genomic hybridization]

INTRODUCTION

Few conventional cytogenetic studies of squamous cell carcinoma (SCC) have been performed to date. The introduction of cytogenetic techniques such as comparative genomic hybridization (CGH) has resolved some of the problems associated with conventional cytogenetics. The aim of this study was to analyze the presence of genetic abnormalities in a series of patients with SCC using the technique of array CGH.

MATERIAL AND METHODS

The study included 8 patients (7 men and 1 woman; mean age, 75 years) diagnosed with primary SCC. DNA was extracted from frozen tissue and analyzed by array CGH.

RESULTS

All cases had genetic alterations, with gains more frequent than losses. The chromosomal regions with gains, in descending order of frequency, were as follows: 5p15.2, 9q31.3-q33.2, 13q, 18q22, 1p21-p22, 1q24-q25, 3p13, 4q33-q34 (HMGB2, SAP30), 20p12.2 (JAG1), 21q21.1, and Xq21.33. The region 9p13.1-p13.3 was the only one to display recurrent loss. No correlation was observed between the presence of gains or losses and the clinical and pathological characteristics of the tumors.

CONCLUSIONS

This is the first study to use the technique of array CGH to analyze genetic alterations in SCC. The finding of certain previously described aberrations (gain of 5p) suggests the existence of recurrent abnormalities. Likewise, the observation of alterations in small regions of chromosome 1 highlights the sensitivity of the technique to detect small changes. Application of the technique to a larger series of cases will provide greater insight into the genetic abnormalities implicated in the process of tumorigenesis in SCC.

Molecular prognostic factors in penile cancer

OBJECTIVES

Penile cancer is a rare tumour in developed countries but more common in South America and East Africa. Although pathological prognostic factors have been established, there is great interest in evaluating molecular markers which correlate with prognosis and outcome.

METHODS

We have reviewed the current status of our understanding of the molecular biology of penile cancer in order to identify established and potential prognostic factors in penile cancer. We have conducted an extensive literature search to review the current understanding of the role of prognostic markers in penile cancer.

RESULTS

Although several markers have been evaluated, currently the clinical application of these markers is limited. HPV positive tumours show a variable prognostic outcome. P53 status may correlate with survival in T1 disease but further studies are required to establish the link to lymph node spread.

CONCLUSIONS

Pathological variables are well-established but further work is required to investigate the role of molecular markers. The development of molecular prognostic markers is important for the surveillance of patients and prediction of lymph node involvement as well as a prognostic marker for survival.

Screening of microsatellite markers in penile cancer reveals differences between metastatic and nonmetastatic carcinomas

Penile cancer, observed only rarely in the western world, represents a carcinoma that may be cured by resection of primary lesion and in case of lymph node metastasis by early lymph node dissection. This early inguinal lymphadenectomy bares a significant better survival even in cases of nonpalpable lymph nodes, but carries also a high risk of overtreatment, especially in lower tumor stages. Due to the low incidence, only few data are available on the molecular genetic background of this tumor, especially concerning tumor progression and metastasis. Therefore, we studied 62 microsatellite markers in 28 penile carcinomas searching for markers predicting progression or outcome. LOH in more than 25% of primary tumors was found on six different chromosomes, including 2q, 6p, 8q, 9p, 12q and 17p13. Statistically significant correlations could be established in D6S260 to clinical outcome and in markers from chromosomes 6, 9 and 12 to tumor stage and metastasis. These regions are worthy for further analysis concerning tumor suppressor genes and metastasis suppressor genes.

Molecular and genetic pathways in penile cancer

Penile cancer is a rare malignancy affecting more than 400 men per year in the UK. Studies on the aetiopathogenesis of this cancer have focused on its association with the human papilloma virus; however, there have also been several studies on the genetic and molecular changes that occur. Human papilloma virus has shown differential levels of prevalence in association with different types of penile cancer. The virus seems to act as a trigger for this disease via its oncogenes. We review this process, and assess the independent genetic events that occur in penile cancer. Knowledge of this cancer is progressing slowly and could be furthered by multicentre cooperation and the formation of national tumour banks, which will aid the development of novel therapeutic agents to reduce the morbidity and mortality of penile cancer.

Detection and expression of Epstein-Barr Virus (EBV) DNA in tissues from penile tumors in Brazil

Epstein-Barr Virus (EBV) is prevalent in all human populations and high titers of antibody correlate with specific malignancies such as Burkitt's lymphoma, nasopharyngeal carcinoma, and Hodgkin's disease. Our study detected EBV DNA in 20 of 21 penile tumor samples using PCR reaction. Expression of EBV protein LMP-1 was identified in tumor cells from two EBV PCR-positive tumors. Our findings indicate that EBV can be implicated in rising and/or progression of penile tumors independently of the histological type.

[Penile cancer]

Penile carcinoma is a tumoral condition of inconsistent incidence. Its biological and etiological features are under permanent scientific review. Such circumstance is increased by the growing awareness of a greater demand of anything related with the patients' quality of life. This paper reviews the latest controversies guiding current therapeutic approaches in penile cancer. An analysis is made through a revision of the lymphadenectomy indication and its therapeutic value, criteria related to technical aspects and indications. At the same time, the criteria that should preside over the choice between conservative or radical options are established and emphasis is placed on the growing role of prevention in tumoral conditions and the contribution of innovative gene therapy regimes.