Role of Toll-like receptors in cervical, endometrial and ovarian cancers: A review

Objective. The Toll-like receptors (TLRs) have been implicated in inflammation, innate immunity and cancer. The goal of this paper is to review the available published research about Toll-like receptors and their roles in gynecologic malignancies. Methods. A Medline search was conducted and published articles from the late 1990s to the present (2014) were reviewed using search phrases, Toll-like receptors and cervical, endometrial and ovarian cancers. Results. TLR4 and TLR5 are commonly absent in normal cervix, however TLR5 expression is strong in high grade cervical dysplasia as well as invasive cancer. The expression of TLR3 and TLR4 is low in endometrial cancer. TLR2, TLR3, TLR4 and TLR5 are highly expressed in normal and neoplastic ovarian epithelium. TLR3 has been shown to have a dual function: it can contribute to tumor elimination by upregulation of interferons alpha and beta (INF) and natural killer cell (NK) activation or it can indirectly contribute to tumor progression. Conclusions. Inflammation is an essential element in tumorigenesis. Toll-like receptors can trigger an inflammatory response and cell survival in the tumor micro-environment. TLRs are critical immunomodulators that may play an important role in the development of gynecologic cancers. Currently TLR agonists are being investigated for a potential role as an adjuvant in the treatment of gynecologic malignancies. (C) 2014 Elsevier Inc. All rights reserved.