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.
Pancreatic ductal adenocarcinoma (PDAC) is not sensitive to most chemotherapy drugs, leading to poor chemotherapy efficacy. Recently, Trametinib and Palbociclib have promising prospects in the treatment of pancreatic cancer. This article aims to explore the effects of Trametinib on pancreatic cancer and address the underlying mechanism of resistance as well as its reversal strategies. The GDSC (Genomics of Drug Sensitivity in Cancer) and CTD2 (Cancer Target Discovery and Development) were utilized to screen the potential drug candidate in PDAC cell lines. The dose-increase method combined with the high-dose shock method was applied to induce the Trametinib-resistant PANC-1 and MIA PaCa-2 cell lines. The CCK8 proliferation assay, colony formation assay, flow cytometry, and western blot were conducted to verify the inhibitory effect of Trametinib and Palbociclib. RNA-seq was performed in resistant PDAC cell lines to find the differential expression genes related to drug resistance and predict pathways leading to the reversal of Trametinib resistance. The GDSC and CTD2 database screening revealed that Trametinib demonstrates a significant inhibitory effect on PDAC. We found that Trametinib has a lower IC