The CpG island methylator phenotype (CIMP), MLH1 methylation, TP53, and KRAS mutation statuses were characterized in 214 GCs in relation to their clinicopathological features and prognosis.
Although KRAS mutations in GC are linked with MSI in the majority of cases, KRAS mutations with MSS status presented with a poor prognosis and a worse outcome.
Overall, our results indicate that prolonged MAPK pathway inhibition could result in acquired resistance which is associated with increased malignant phenotype in KRAS mutant GC and pharmacological targeting c-MET and PI3K/mTOR could overcome this problem.
Gastric cancer (GC) is characterized by amplifications of receptor tyrosine kinases (RTK) and KRAS, therefore, targeting of the RTK/KRAS downstream pathways could help to broaden the applicability of molecular targeted therapy for GC.
We assessed the mutational status of the entire KRAS coding sequence in 19 MSI-GC cases by multiplex PCR/sequencing and used peak height ratio determined from electropherograms from KRAS heterozygous mutants and histopathological evaluation to infer tumour heterogeneity in GC.
Cetuximab, an immunoglobulin G1 chimeric monoclonal antibody directed against the epidermal growth factor receptor, is currently considered to be the strategy with the most potential for the treatment of gastric cancer due to the low frequency of KRAS mutations in patients with gastric cancer.
Overall, 78% of GC cases harbored one clinically relevant GA or more, with the most frequent alterations being found in TP53 (50%), ARID1A (24%), KRAS (16%), CDH1 (15%), CDKN2A (14%), CCND1 (9.5%), ERBB2 (8.5%), PIK3CA (8.6%), MLL2 (6.9%), FGFR2 (6.0%), and MET (6.0%).
In summary, amplified PAK1, as well as KRAS amplification/mutation, may represent unique opportunities for developing targeted therapeutics for the treatment of gastric cancer.
Our data demonstrated that the T allele of the let-7 binding site polymorphism rs712 in KRAS 3' UTR was associated with a significantly increased risk of GC, suggesting that the KRASrs712 polymorphism may be a genetic marker for the development of GC.
Integration of information on the genetic and epigenetic alterations revealed that the GCs with the CpG island methylator phenotype (CIMP) tended to have mutations of oncogenes, CTNNB1, ERBB2, KRAS, and PIK3CA.
We investigated the association of p53 and K-ras gene mutation and Helicobacter pylori infection in patients with gastric cancer (GC) and peptic ulcer disease (PUD) attending a tertiary care hospital in north India.
These results support KRAS mutation may only be involved in carcinogenesis of partial gastric cancers and the different mutation types of KRAS may take part in development of gastric cancer at different stages.
Amplification of the KRAS locus was detected in 15% (3/20) of gastric cancer cell lines (8-18-fold amplification) and 4.7% (4/86) of primary gastric tumors (8-50-fold amplification).
In this review, we will discuss the involvement of E-cadherin, EGFR, ERBB2, MMR genes, KRAS, and PIK3CA in the development and progression of gastric cancer and their role as biomarkers or as novel putative targets for therapy.