Multispecific targeting of glioblastoma with tumor microenvironment-responsive multifunctional engineered NK cells

Abstract

Tumor antigen heterogeneity, a severely immunosuppressive tumor microenvironment (TME) and lymphopenia resulting in inadequate immune intratumoral trafficking, have rendered glioblastoma (GBM) highly resistant to therapy. To address these obstacles, here we describe a unique, sophisticated combinatorial platform for GBM: a cooperative multifunctional immunotherapy based on genetically engineered human natural killer (NK) cells bearing multiple antitumor functions including local tumor responsiveness that addresses key drivers of GBM resistance to therapy: antigen escape, immunometabolic reprogramming of immune responses, and poor immune cell homing. We engineered dual-specific chimeric antigen receptor (CAR) NK cells to bear a third functional moiety that is activated in the GBM TME and addresses immunometabolic suppression of NK cell function: a tumor-specific, locally released antibody fragment which can inhibit the activity of CD73 independently of CAR signaling and decrease the local concentration of adenosine. The multifunctional human NK cells targeted patient-derived GBM xenografts, demonstrated local tumor site–specific activity in the tissue, and potently suppressed adenosine production. We also unveil a complex reorganization of the immunological profile of GBM induced by inhibiting autophagy. Pharmacologic impairment of the autophagic process not only sensitized GBM to antigenic targeting by NK cells but promoted a chemotactic profile favorable to NK infiltration. Taken together, our study demonstrates a promising NK cell–based combinatorial strategy that can target multiple clinically recognized mechanisms of GBM progression simultaneously.

Systematic Analysis of Chemokines Reveals CCL18 is a Prognostic Biomarker in Glioblastoma

“…The microenvironment (TME) plays an essential role in the progression and metastasis of GBM. 33 Generally, TME is enriched for pro-inflammatory cytokines, chemokines, and their complex cross-talk with their receptors influences the development of cancers. 23 For example, macrophages can be recruited into the tumor microenvironment by the CCL2-CCR2 signaling, associated with poor patient prognosis in breast cancer.…”

Natural killer cell homing and trafficking in tissues and tumors: from biology to application

“… 223 In glioblastoma, pharmacological inhibition of autophagy by chloroquine promoted the expression of the chemokines CCL5 and CXCL10 by tumor cells, enhancing infiltration of CAR NK cells into the tumor tissues. 224 We reported that herpes simplex virus 1-based oncolytic virus increased NK cell infiltration in various mouse models of glioblastoma. 225 – 231 However, the detailed mechanisms underlying the interaction between chemokines and their receptors have yet to be explored.…”

Glioblastoma Microenvironment and Cellular Interactions

“…Furthermore, in a gastric cancer study, the intratumorally NK cells (CD57 + ) were associated with poor outcomes [ 266 ]. Another study showed that the pharmacologic impairment of autophagy functions acts as an immuno-modulator and promotes the genetically-engineered human NK cells into tumor sites, resulting in effective anti-GBM activity [ 267 ]. Therefore, more studies are required in order to determine the intra-tumoral impact of infiltrated NK cells and their therapeutic efficacy.…”