With a 2-3% lifetime risk,endometrial carcinoma (EC) is the most common gynecologic malignancy in developed countries,and the incidence and mortality is increasing.There is hence a major need to develop new and effective intervention strategies to EC.By employing a powerful experimental model,we aim to address this unmet need.Over 90% of the BDII strain females spontaneously develop EC that in pathogenesis resemble those of human.It has been shown that stimulation of Toll-like receptor (Tlr) 9 in the mouse genital tract leads to activation of innate and adaptive immune responses as well as protection against local viral infections.We thus hypothesized that induction of local immune response may similarly interfere the development of spontaneous ECs in BDⅡ rats.To test this,we examined expression of rat Tlrs in a panel of BDII rat EC as well as normal endometrium from BDⅡ and BN rats (as control) at different phases of estrus cycle using real-time RT-PCR.Results of Tlr expression experiments suggested at least three candidate receptors (Tlr9,Cdl80,and Tlr7) for targeting with intravaginal administration of Tlr ligands.We additionally assessed the ensuing local immune response after vaginal administration of Tlr9 in this model.