Epidermal growth factor receptor (EGFR)-RAS signaling pathway in penile squamous cell carcinoma

PLoS One. 2013 Apr 24;8(4):e62175. doi: 10.1371/journal.pone.0062175. Print 2013.

Abstract

Penile Squamous Cell Carcinoma (SCC) is a rare cancer with poor prognosis and limited response to conventional chemotherapy. The genetic and epigenetic alterations of Epidermal Growth Factor Receptor (EGFR)-RAS-RAF signaling in penile SCC are unclear. This study aims to investigate four key members of this pathway in penile SCC. We examined the expression of EGFR and RAS-association domain family 1 A (RASSF1A) as well as the mutation status of K-RAS and BRAF in 150 cases of penile SCC. EGFR and RASSF1A expression was evaluated by immunohistochemistry. KRAS mutations at codons 12 and 13, and the BRAF mutation at codon 600 were analyzed on DNA isolated from formalin fixed paraffin embedded tissues by direct genomic sequencing. EGFR expression was positive in all specimens, and its over-expression rate was 92%. RASSF1A expression rate was only 3.42%. Significant correlation was not found between the expression of EGFR or RASSF1A and tumor grade, pT stage or lymph node metastases. The detection of KRAS and BRAF mutations analysis was performed in 94 and 83 tumor tissues, respectively. We found KRAS mutation in only one sample and found no BRAF V600E point mutation. In summary, we found over-expression of EGFR in the majority cases of penile SCC, but only rare expression of RASSF1A, rare KRAS mutation, and no BRAF mutation in penile SCC. These data suggest that anti-EGFR agents may be potentially considered as therapeutic options in penile SCC.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Adult
  • Aged
  • Aged, 80 and over
  • Carcinoma, Squamous Cell / genetics
  • Carcinoma, Squamous Cell / metabolism*
  • Carcinoma, Squamous Cell / pathology
  • ErbB Receptors / genetics
  • ErbB Receptors / metabolism*
  • Gene Expression
  • Humans
  • Lymphatic Metastasis
  • Male
  • Middle Aged
  • Mutation
  • Neoplasm Grading
  • Neoplasm Staging
  • Penile Neoplasms / genetics
  • Penile Neoplasms / metabolism*
  • Penile Neoplasms / pathology
  • Proto-Oncogene Proteins B-raf / genetics
  • Proto-Oncogene Proteins B-raf / metabolism
  • Signal Transduction*
  • Tumor Suppressor Proteins / genetics
  • Tumor Suppressor Proteins / metabolism
  • Young Adult
  • ras Proteins / metabolism*

Substances

  • RASSF1 protein, human
  • Tumor Suppressor Proteins
  • ErbB Receptors
  • Proto-Oncogene Proteins B-raf
  • ras Proteins

Grants and funding

This work was supported partly by the National Natural Science Foundation of China (31070801 and 81272457). The funder had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.