NLRP12-mediated Glioblastoma-Astrocyte Cross-talk Promotes Tumor Growth

Nucleotide-binding domain leucine-rich repeat-containing receptors (NLR) are cytosolic pattern recognition receptors that regulate inflammation by sensing pathogen-associated molecular patterns (PAMPs) and damage-associated molecular patterns (DAMPs). NLRP12 is a cytosolic protein with inflammation-promoting and inflammation-attenuating properties. NLRP12 exhibits tumor-suppressive or tumor-promoting effects that may be cancer, cell-type, context-dependent, aided by differences in the microenvironment contributing to the pathophysiology of hepatocellular carcinoma, prostate cancer, colitis-associated cancer, and glioblastoma (GBM). GBM is a grade IV malignant brain tumor with poor patient survival and high tumor recurrence due to a heterogeneous cell population and angiogenesis. Our previous research reported NLRP12 as a potential prognostic marker for GBM with high expression in GBM patient tissues. In the present study, we investigated the role of NLRP12-mediated signalling between GBM and tumor-adjacent astrocytes, using a comprehensive panel of experimental models, including LN-229 GBM and SVG astrocyte cell lines, cell line-derived spheroids, patient-derived primary glioma cells, and patient-derived glioma organoids. We report that NLRP12 deficiency reduces cell proliferation and viability in the LN-229 cells, but increases these parameters in SVG cells. Furthermore, NLRP12 -deficient LN-229 cells display attenuated ability to form three-dimensional spheroids, indicating a role of NLRP12 in anchorage-independent growth, which is considered a hallmark of tumorigenicity. Analysis of patient-derived glioma tissue and patient-derived GBM organoids revealed differential expression of NLRP12. Our findings suggest that NLRP12 modulates GBM cell proliferation, viability, and anchorage-independent growth in a cell-context dependent manner. The cell-type-specific roles of NLRP12 may underlie its complex contribution to GBM pathophysiology with implications for therapy and prognosis.