<prompt> Gastric carcinoma is associated with all EXCEPT ?Inactivation of p53Over expression of C-erbOver expression of C-metActivation of RAS  <response>: Ans. is d Activation of RAS In the course of multi-step stomach carcinogenesis, various genetic and epigenetic alterations of oncogenes, tumor-suppressor genes, DNA repair genes, cell cycle regulators and cell adhesion molecules are involved. Genetic alteration in gastric cancer include: Intestinal type gastric cancer: K-ras mutation, APC mutation, pS2 methylation, HMLH1 methylation, p I ema methylation, p 73 deletion and C-erb B-2 amplification. Diffuse type gastric caner: CDH I gene E-Cadherin mutation, K-sam amplification. For both type: Telomerase reduction telomerase shoening, hTE expression, genetic instability, overexpression of the cyclin E CDC25B E2F I genes,p53 mutations, reduced expression, CD44 aberrabont transcripts, and amplification of the C-met Cyclin E genes. Coming to question: All the given four genetic alterations may be associated with stomach cancer. However among the given options K-ras is best answer as it is associated with gastric cancer in minimum percentage amongst given options: Source: Textbook of mechanism of carcinogenesis and cancer prevention K-ras mutation -4 10 p53 mutation 30-60 C-erb B-2 amplifcation -- 20 C-met amplifciation -- 20 