In Vivo Effect of Luteolin during Oxaliplatin Treatment for Colorectal Cancer

Abstract

Phytochemicals that induce nuclear factor (erythroid‐derived 2)‐like 2 (Nrf2) can lower cellular oxidative stress and thus favor cell viability. Considering our previous in vitro study demonstrating that strong antioxidative called luteolin interfered with the anticancer effect of oxaliplatin on HCT116, we hypothesized that luteolin administration would be unadvantageous during oxaliplatin‐based chemotherapy. To test this hypothesis, HCT116 xenograft mouse model was established in BALB/c nude mice. Once palpable tumors were developed after HCT116 cells were subcutaneously transplanted on both flanks of each mouse, mice were randomly allocated into four groups that were intraperitoneally injected with (1) vehicle only (control), (2) oxaliplatin at a dose of 10 mg/kg body weight (BW), (3) luteolin at 50 mg/kg BW, or (4) combination of luteolin and oxaliplatin. Tumor size and body weight were regularly monitored (three times a week) for three weeks. Results demonstrated that oxaliplatin treatment inhibited the growth of xenografted tumors as expected, luteolin treatment had little effect on the tumor size, and combinatorial treatment of oxaliplatin and luteolin most suppressed tumor growth. In addition, oxaliplatin‐luteolin combo reduced heme oxygenase‐1 (HO‐1) protein expression compared to oxaliplatin alone. Moreover, luteolin alone treatment enhanced protein expressions of p53 and its downstream molecule p21. These findings were suggestive of in vivo synergistic effect of combinatorial treatment of oxaliplatin and luteolin at the tested doses in this study and the possible coordinated regulation via p53 and/or HO‐1‐mediated cytoprotection in HCT116 xenograft tumor growth. According to the current observations, our hypothesis ought to be reconsidered; luteolin could advantageously hamper tumor growth during oxaliplatin treatment in colon cancer.This abstract is from the Experimental Biology 2019 Meeting. There is no full text article associated with this abstract published in The FASEB Journal.