A link between expression level of long-non-coding RNA in breast tissue of healthy women and obesity.

[BACKGROUND] Epidemiological and experimental literature indicates that the risk of breast cancer incidence is strongly linked to hormone-dependent factors, including reproductive history and obesity. However, the molecular mechanisms underlying the association between these factors and breast cancer risk are poorly understood. The aim of this study, therefore, was to determine whether obesity and reproductive history are associated with expression levels of two breast cancer-related long non-coding RNAs (lncRNAs), namely and in cancer-free breast tissues of women.

[METHODS] In the current research, 145 healthy women were recruited, and the quantitative expression levels of the two lncRNAs were determined through qPCR assay after gathering the mammoplasty breast tissue samples.

[RESULTS] It was found that women with body mass index (BMI)≥30 kg/m and BMI 25-29 kg/m show a low expression of compared to the BMI<25 kg/m (=0.031 and =0.027, respectively). Then, the correlation analysis disclosed a negative correlation of low expression with increasing BMI (r=-0.194, =0.019). Interestingly, this analysis demonstrated a negative correlation between low expression of the and high BMI in women with menarche age below 14 (r=-221; =0.028). Lastly, it was also revealed that there was a negative association of the low expression level of with increasing BMI in women through regression models (B=-0.048, =0.019).

[CONCLUSIONS] These findings suggest interesting clues about the links between high BMI and the expression levels of in non-diseased breasts that may help us better understand the underlying mechanisms through which obesity contributes to breast carcinogenesis. However, such results need more validations in future research.