Immunology of cervical cancer

ABSTRACT Optimal function of the immune system allows the recognition and elimination of infected and tumor cells. However, these cells can develop mechanisms to evade the cellular immune response. In human papillomavirus (HPV) infection, dysregulation of major histocompatibility complex Class I molecules and other components of the innate immune system promote the survival of infected cells by allowing the infection to persist which, in turn, favors the development of cancer. Further, tumor cells possess inherent mechanisms designed to block the recognition and activation of cytotoxic lymphocytes: particularly, HPV proteins such as E1 and E2 and oncoproteins E5, E6, and E7 that inhibit immune mechanisms and/or stimulate the expression of immunosuppressive cytokines. These mechanisms include a decrease in receptor activation and costimulating molecules on the surface of immune cells, as well as the constitutive expression of molecules that inhibit their function, which allow HPV persistence and tumor progression. Immunotherapy-based therapeutic options are positioned as excellent candidates for the treatment of cervical cancer.

Immunotherapy treatment against cervical cancer

ABSTRACT Cervical cancer (CC) is one of the most common gynecological tumors and an important health problem, especially in developing countries. The vast majority of patients in early stages are cured of the disease with surgical treatment and with concomitant chemoradiotherapy in locally advanced stages. However, in patients with recurrent, persistent, or metastatic cervical CC, the effectiveness of treatment is limited, except for the combination of chemotherapy based on platinum doublets plus bevacizumab, the treatment that has achieved the best results to date. Programmed cell death-1/PD ligand-1 (PD-1/PD-L1) inhibitors could be a novel and cutting-edge therapeutic option to improve clinical outcomes in this group of patients. Thus far, there are a few Phase I/II clinical trials that have assessed the usefulness of pembrolizumab and nivolumab in this group of patients; these include the KEYNOTE 028, KEYNOTE 158, and CHECKMATE 358 trials, in which clinical benefit has been proven with PD-1/PD-L1 inhibitors in recurrent, persistent, or metastatic CC, as second-line treatment. There are also some ongoing trials that could provide further evidence on the PD-1/PD-L1 pathway as a therapeutic target in CC. In this review, we will focus on the usefulness of these PD-1/PDL1 inhibitors in CC, as well as on trials that are still in the recruitment phase, to confirm their effectiveness in this clinical setting.