The association of dietary protein and fiber with RhoA gene expression of breast

Abstract

Background: Food intake and physical activity could be involved in different episodes of carcinogenesis. Some studies showed that high protein intake, especially animal protein is associated with increased risk of breast cancer. A few cohort studies proposed inverse association between dietary fiber and breast cancer risk in postmenopausal women. Ras homology gene family (Rho) takes apart in cell mobility. Based on experimental studies, RhoA is rarely detectable in tumor free tissue of the breast, while highly expressed in breast tumors. In this study, we aimed to investigate the correlation of the dietary protein and fiber with RhoA gene expression. Materials and Methods: This cross-sectional study was conducted on pathological confirmed primary breast cancer patients of Nornejat hospital from 2015 to 2016. Patients included after acquiring the inclusion criteria of the study. Validated food frequency questionnaire (FFQ) was used in order to obtain dietary history of studied population. Gene expression of RhoA was evaluated by quantitative real-time polymerase chain reaction (qRT-PCR). Results: The white meat intake was inversely associated with RhoA expression in all patients (β=-0.18) and ALNM+ patients (β= -0.31; P<0.05). RhoA expression also was associated with animal protein intake (β=0.38) and red meat intake (β=0.32) after adjustment for confounders in this patients (P<0.05). Dietary fiber after log. transformation and adjustment for confounders was associated directly with RhoA expression (β=0.27; P<0.05). In ALNM- patients, insoluble fiber (β=0.44) was in direct association with RhoA expression(P<0.05). The expression of RhoA was significantly associated with soluble (β=0.85) and insoluble fiber (β=0.94) intakes among ER- patients (P<0.05) Conclusion: Dietary protein intake was in association with RhoA expression. Animal protein intake was directly associated with RhoA expression. However, white meat protein sources were inversely related to RhoA expression. Dietary fiber intake and its soluble and insoluble subtypes were in direct association with RhoA expression