Over-expression of RAB5A gene has been proved to be associated with neoplasia metastasis.Over-expression of RAB5A genes plays an important role in tumor invasion and metastatic phenotype formation of human lung adenocarcinoma cells; and antisense RNA can interrupt the translation of RAB5A gene.RAB5A was a directly target of miR-13a, and its mRNA and protein level was negatively regulated by miR-13a. Immunohistochemistry verified RAB5A was upregulated in breast cancer tissues. RAB5A gene was abnormally expressed in luteinized granulosa cells of obese patients with polycystic ovary syndrome, which may help explain high FSHR levels found in this syndrome.