Epidermal Growth Factor Receptor, Excision-Repair Cross-Complementation Group 1 Protein, and Thymidylate Synthase Expression in Penile Cancer

Non-Coding RNA in Penile Cancer

Penile cancer (PC) still presents a health threat for developing countries, in particular Brazil. Despite this, little progress has been made on the study of markers, including molecular ones, that can aid in the correct management of the patient, especially concerning lymphadenectomy. As in other neoplasms, non-coding RNAs (ncRNAs) have been investigated for penile cancer, with emphasis on microRNAs, piRNAs (PIWI-interacting small RNAs), and long non-coding RNAs (LncRNAs). In this context, this review aims to assemble the available knowledge on non-coding RNA linked in PC, contributing to our understanding of the penile carcinogenesis process and addressing their clinical relevance. ncRNAs are part of the novel generation of biomarkers, with high potential for diagnosis and prognosis, orientating the type of treatment. Furthermore, its versatility regarding the use of paraffin samples makes it possible to carry out retrospective studies.

Penile Cancer-Derived Cells Molecularly Characterized as Models to Guide Targeted Therapies

Penile cancer (PeCa) is a common disease in poor and developing countries, showing high morbidity rates. Despite the recent progress in understanding the molecular events involved in PeCa, the lack of well-characterized in vitro models precludes new advances in anticancer drug development. Here we describe the establishment of five human primary penile cancer-derived cell cultures, including two epithelial and three cancer-associated fibroblast (CAF) cells. Using high-throughput genomic approaches, we found that the epithelial PeCa derived- cells recapitulate the molecular alterations of their primary tumors and present the same deregulated signaling pathways. The differentially expressed genes and proteins identified are components of key oncogenic pathways, including EGFR and PI3K/AKT/mTOR. We showed that epithelial PeCa derived cells presented a good response to cisplatin, a common therapeutic approach used in PeCa patients. The growth of a PeCa-derived cell overexpressing EGFR was inhibited by EGFR inhibitors (cetuximab, gefitinib, and erlotinib). We also identified CAF signature markers in three PeCa-derived cells with fibroblast-like morphology, indicating that those cells are suitable models for PeCa microenvironment studies. We thus demonstrate the utility of PeCa cell models to dissect mechanisms that promote penile carcinogenesis, which are useful models to evaluate therapeutic approaches for the disease.

Current Management Strategy for Penile Cancer and Future Directions

PURPOSE OF REVIEW

The aim of this review is to evaluate the trends in multidisciplinary management of localized penile cancer and systemic therapy for advanced disease in the evolving era of targeted and immune checkpoint therapy.

RECENT FINDINGS

Organ preservation (surgical or incorporating radiation) and reconstructive techniques are important considerations for quality of life in penile cancer survivors. Although local recurrence may be higher with organ preservation, salvage therapy appears successful. Inguinal and pelvic node management requires multidisciplinary care, including chemotherapy; optimal use of radiation has not been fully defined. Advanced in understanding the biology of penile cancer, particularly with regard to epidermal growth factor receptor (EGFR) and HPV status, have led to clinical trials of targeted and immune therapy for patients with refractory disease. Refinements in the management of penile cancer are occurring, though level 1 evidence remains scarce. Referral to specialized centers will facilitate successful completion of clinical trials to advance standard care in this disease.

Epidermal growth factor receptor as an adverse survival predictor in squamous cell carcinoma of the penis

Penile carcinoma (PC) is more frequent in underdeveloped countries, generally is diagnosed at an advanced stage when therapeutic options are restricted, and thus is associated with high morbidity/mortality rates. Recent studies have demonstrated clinical benefits with epidermal growth factor receptor (EGFR)-targeted therapy in patients with PC, although there is no test that provides accurate patient selection. The aim of the present study was to evaluate the prognostic value of EGFR gene and protein status in tumor samples from patients with primary penile squamous cell carcinoma. We assessed the expression of wild-type and 2 mutant EGFR isoforms (delA746-E750 and mL858R) by immunohistochemistry in 139 samples, of which 49 were also evaluated for EGFR copy number by fluorescence in situ hybridization (FISH). Positive immunohistochemical staining of wild-type and mutant EGFR was evidenced by complete and strong membranous staining. For FISH analysis, cases were considered unaltered, polysomic, or amplified, as determined by signals of the EGFR gene and chromosome 7. An independent cohort of 107 PC samples was evaluated for mutations in EGFR, KRAS, and BRAF. Protein overexpression was noted in nearly half of the cases and was associated with cancer recurrence (P=.004) and perineural invasion (P=.005). Expression of the 2 mutated EGFR isoforms was not observed. The FISH status was not associated with protein expression. Altered FISH (polysomy and gene amplification) was an independent risk factor for dying of cancer. Only 1 patient of 107 presented KRAS mutations, and no mutations of EGFR or BRAF were observed.