Lirilumab and Avelumab Enhance Anti-HPV+ Cervical Cancer Activity of Natural Killer Cells via Vav1-Dependent NF-κB Disinhibition.

Hongli Liu,Jing Liu,Mengjun Liu,Fuliang Chen,Hongtao Wang,Xiaojing Wang,Shengping Min,Sihui Zhou,Nan Wu,Yuan Zhang

doi:10.3389/fonc.2022.747482

Abstract

BackgroundWe investigated the efficacy and mechanism of the anti-KIR immunotherapy lirilumab and anti-PD-L1 immunotherapy avelumab on natural killer (NK) cell activity against HPV+ cervical cancer.MethodsNK cell-mediated lysis of autologous biopsy-derived malignant cervical squamous cells and normal cervical squamous cells were measured by europium-release cytotoxicity assays. Cytokine and granzyme B release were measured by ELISPOT effector-cell-based assays and ELISA. Murine cervical cancer tumor models were constructed to assess implanted tumor volumes over time and intratumoral immune cell infiltration. Receptor-crosslinking and plate-immobilized antibody stimulation studies, with or without p65 and Vav1 silencing, were used to investigate NF-κB pathway disinhibition in NK cells.ResultsLirilumab and avelumab each enhanced NK cell disinhibition and NK cell-mediated lysis of autologous cervical cancer cells in vitro while reducing HPV+ tumor volumes and increasing intratumoral NK cell infiltration and cytolysis in vivo. Moreover, lirilumab and avelumab each promoted NK cell NF-κB disinhibition as well as stimulated cytokine and granzyme B expression in a NF-κB-dependent manner. Lirilumab+avelumab enhanced all aforementioned effects compared to either monotherapy. Vav1 silencing eliminated disinhibition of NF-κB signaling by lirilumab and avelumab, indicating their disinhibiting effects are Vav1-dependent.ConclusionsThis study supports a novel approach to enhancing NK cell lysis against HPV+ cervical cancer cells through combining lirilumab and avelumab.

Highlights

Cervical cancer is the fourth-highest ranking malignancy in terms of incidence among women globally [1], and human papillomavirus (HPV) is the predominant cause of cervical cancer [2]
This study supports a novel approach to enhancing Natural killer (NK) cell lysis against HPV+ cervical cancer cells through combining lirilumab and avelumab
As NF-kB signaling has been shown to play a critical role in receptor-regulated NK cell activity [18], we discovered the cooperative disinhibition of NF-kB signaling by lirilumab and avelumab in NK cells, converging at the level of Vav1 and the downstream NF-kB p65 subunit

Summary

Introduction

Cervical cancer is the fourth-highest ranking malignancy in terms of incidence among women globally [1], and human papillomavirus (HPV) is the predominant cause of cervical cancer [2]. Natural killer (NK) cells, when activated by surface receptor cues, play a key role against malignant tumors by directly killing transformed cells with proteolytic granzymes and secreting immunoregulatory cytokines, such as interferon (IFN)-g, macrophage inflammatory proteins (MIPs), interleukins (IL-8, IL-10), and TNF-a [3, 4] Release of these cytokines recruits other immune cells (e.g., T-helper 1 [Th1] cells, myeloid cells) to the site and induces their anti-tumor response [3, 4]. Monoclonal antibodies (mAbs) have been developed to enhance the innate NK cell response against cervical cancer cells, including the antiPD-1 mAbs nivolumab and pembrolizumab and the anti-PD-L1/ 2 mAbs MPDL3280A and AMP-224 [8, 9] These antibodies inhibit the interaction between PD-L1 on tumor cells and its receptor PD-1 on NK cells, thereby abrogating the immunosuppressive signal and enhancing immune cell disinhibition [10, 11]. We investigated the efficacy and mechanism of the anti-KIR immunotherapy lirilumab and anti-PD-L1 immunotherapy avelumab on natural killer (NK) cell activity against HPV+ cervical cancer

Methods

Results

Conclusion