Abstract
Background: With a global prevalence of about 10%, gastric cancer is among the most prevalent cancers. Currently, there has been an ongoing trend toward investigating genetic disruptions in different cancers because they can be used as a target-specific therapy. We aimed to systemically review some gene expression patterns in gastric cancer. Methods: The current systematic review was designed and executed in 2020. Scopus, PubMed, Cochrane Library, Google Scholar, web of knowledge, and Science Direct were searched for relevant studies. A manual search of articles (hand searching), reference exploring, checking for grey literature, and seeking expert opinion were also done. Results: In this review, 65 studies were included, and the expression pattern of HER2/ ERBB2, ER1/Erb1/EGFR, PIK3CA, APC, KRAS, ARID1A, TP53, FGFR2 and MET was investigated. TP53, APC, KRAS, and PIK3CA mutation cumulative frequency were 24.8 (I(2)=95.05, Q value=525.53, df=26, P<0.001), 7.2 (I(2)=89.79, Q value=48.99, df=5, P<0.001), 7.8 (I(2)=93.60, Q value=140.71, df=9, P=0.001) and 8.6 (I(2)=80.78, Q value=525.53, df=9, P<0.001) percent, respectively. Overexpression was investigated for HER1/ Erb1/EGFR, PIK3CA, APC, KRAS, ARID1A, TP53, CCND1, FGFR2, MET and MYC. The frequency of TP53 and HER2/ERBB2 were 43.1 (I(2)=84.06, Q value=58.09, df=9, P<0.001) and 20.8 (I(2)=93.61, Q value=234.89, df=15, P<0.001) percent, respectively. Conclusion: More research is encouraged to investigate the genes for which we could not perform a meta-analysis.