Evaluation of Leptin Receptor Q223R (rs1137101) Polymorphism Based on Histopathological and Body Mass Index Characteristics in Iranian Females with Breast Cancer

The mechanism of the relationship between obesity and the risk of breast cancer is still unknown.

The current study aimed at evaluating the relationship between the leptin receptor Q223R (Gln/Arg) polymorphism, body mass index (BMI), and histopathological changes in patients with breast cancer.

A total of 158 patients with breast cancer and 158 healthy subjects within the same age range were recruited. After taking blood sample, DNAs were extracted using the salting-out method. Then, the polymerase chain reaction-restriction fragment length polymorphism technique was used for genotyping. The histopathological characteristics were determined by the immunohistochemistry technique.

Investigation of the relationship between BMI and alleles showed that the G (Arg) mutant elevated the risk of affection by 2.294 times, while the allele A had a descending effect by 0.375 times. The comparison of genotypes with histopathological changes showed a significant relationship between the GG (Arg/Arg) genotype and higher levels of progesterone receptor expression (P = 0.005), invasive type of cancer (P = 0.010), and stage of the disease (P = 0.003).

People with higher BMI who also carried G (Arg) mutant of Q223R polymorphism were more prone to breast cancer. Also, tissue changes in the ones carrying this allele were more than those harboring the wild-type A (Gln) allele.