KCNH2 and lip and oral cavity carcinoma: Our study provides suggestive evidence that KCNH2 expression and KCNH2-mediated DBP are positively correlated with oral cancer risk, both of which collectively indicate the potential protective impact of KCNH2 inhibition on oral cancer (OR instrument 1 = 0.450, 95% CI = 0.221–0.914; OR instrument 2 = 0.835, 95% CI = 0.717–0.973).