Differential neuropilin isoform expressions highlight plasticity in macrophages in the heterogenous TME through in-silico profiling

HYUN-JEE HAN Marcos Rubio-Alarcon ^* Thomas Allen ^* Sunwoo Lee ^* Taufiq Rahman ^*

• University of Cambridge, Cambridge, United Kingdom

The nuanced roles of neuropilin (NRP) isoforms, NRP1 and NRP2, have attracted considerable scientific interest regarding cancer progression. Their differential expressions across various cancer types are specific to NRP isoforms which are shown in a cancer type-dependent manner. It accounts for the different mechanisms involved, driven by a co-expression of gene-sets associated with overexpressed NRP1 or NRP2. Through single-cell sequencing analyses, we examined gene expressions and cellular heterogeneity within the cancers revealing heightened NRP1 expression in clear cell Renal Cell Carcinoma (ccRCC) and NRP2 in skin cutaneous melanoma (SKCM), specifically both amongst tumour-associated macrophages (TAMs). Both NRP1 + and NRP2 + TAMs exhibit an M2-like polarisation with pro-tumorigenic activities, such as immune suppression and ECM degradation.Notably, through DEGA we discovered previously uncharacterised NRP-related subpopulations for the disaparate cancer types. While the upregulation of gene-sets associated with NRP1 was identified to drive angiogenesis and tumour progression through VEGF signalling, NRP2 showed dual functionality in the TME-dependent manner, which has been illustrated through co-enrichment of the various expected gene signatures in NRP1 + and NRP2 + TAMs, highlighting their distinct roles in regulating macrophage plasticity, tumour invasion, and metastasis. This study aims to establish a foundation for future research, leading to biological experiments with focused gene-sets derived from our findings. This approach can contribute to the development of immunomodulatory strategies targeting specific NRP isoforms in macrophages, tailored to individual cancer types and abnormal expressions of those gene markers, potentially offering a more effective therapeutic approach compared to broad-spectrum NRP inhibition strategies.