Materials and Methods: The present study was a double-blind clinical trial in which neither the oncologist nor the patients were aware of the treatment before and after the intervention. The patients with stomach adenocarcinoma were first recognized and subjected to chemotherapy. A total of 24 patients were randomly selected and included in the case and control groups. The patients in the control group were treated with cisplatin and placebo while those of the case group first received cisplatin with the complementary capsule of fatty acids, namely, Natural Factors Ultimate Omega Factors with a dose of 1200 mg and 3600 mg daily, encompassing three 1200 mg medicines each course for 3 weeks. Three samples of the stomach biopsy were taken from all patients before and after the chemotherapy. All mRNA tissues were extracted out of the biopsy samples. Then, DNA was synthesized based on these samples and the exposition rate of the desired genes was measured using the real-time polymerase chain reaction (PCR) method.

Results: There was a significant decrease in the mean of exposition of the genes in the case group (P = 0.021) compared to the control group (P = 0.001).

Conclusions: Generally, the results revealed that using omega fatty acids 3, 6, and 9 along with cisplatin medicine can be effective in stopping the cell cycle phase G2 in cancerous cells of the stomach tissue.