Siglec-7 glyco-immune binding mAbs or NK cell engager biologics induce potent antitumor immunity against ovarian cancers
Menée in vitro et à l'aide de modèles murins de cancer de l'ovaire, cette étude met en évidence l'intérêt thérapeutique d'anticorps monoclonaux ciblant l'antigène Siglec-7 ou d'anticorps bispécifiques capables de lier à la fois l'antigène Siglec-7 des cellules NK et le récepteur FSHR des cellules cancéreuses
Ovarian cancer (OC) is a lethal gynecologic malignancy, with modest responses to CPI. Engagement of additional immune arms, such as NK cells, may be of value. We focused on Siglec-7 as a surface antigen for engaging this population. Human antibodies against Siglec-7 were developed and characterized. Coculture of OC cells with PBMCs/NKs and Siglec-7 binding antibodies showed NK-mediated killing of OC lines. Anti–Siglec-7 mAb (DB7.2) enhanced survival in OC-challenged mice. In addition, the combination of DB7.2 and anti–PD-1 demonstrated further improved OC killing in vitro. To use Siglec-7 engagement as an OC-specific strategy, we engineered an NK cell engager (NKCE) to simultaneously engage NK cells through Siglec-7, and OC targets through FSHR. The NKCE demonstrated robust in vitro killing of FSHR+ OC, controlled tumors, and improved survival in OC-challenged mice. These studies support additional investigation of the Siglec-7 targeting approaches as important tools for OC and other recalcitrant cancers. Anti-Siglec-7 MAb or Siglec-7 bispecific NK cell engager demonstrate potent targeted OC therapeutic activity in vitro and in vivo.
Science Advances 2023