GSE185013
Blocking of CA-MSC-induced desmoplasia reprograms the tumor immune microenvironment and enhances cancer immunotherapy
We determined the immune cell composition and their gene expression, by performing single-cell RNA sequencing (scRNA-seq), in anti-PD-L1-treated 2F8cis tumors, a hot and immunoresponsive ovarian murine tumor model, and anti-PD-L1-treated 2F8cis/CA-MSC tumors. We also evaluated the ability of hedgehog inhibitor (HHi) therapy to reverse CA-MSC effects. Adipose-derived mesenchymal stem cells (MSC) were cultured with 2F8cis, an ovarian mouse tumor cell line, to generate cancer-associated MSC (CA-MSC). 2F8cis tumor cell alone or 2F8cis/CA-MSCs co-cultured cells at ratio 1:1 were injected into C57BL/6J mice.   Tumor infiltrating CD45+ cells were isolated from anti-PD-L1-treated 2F8cis (Group 1, n=3), anti-PD-L1-treated 2F8cis/CA-MSCs (Group 2, n=3), anti-PD-L1+ IPI-926-treated 2F8cis/CA-MSCs (Group 3, n=3) tumors. Samples were labeled with different TotalSeq oligo-conjugated antibodies and loaded into the Chromium instrument (10x Genomics). The resulting barcoded cDNAs were used to construct libraries.  Single-cell cDNA libraries were then processed for RNA sequencing using an Illumina NextSeq-500 platform. Anti-PD-L1-treated 2F8cis/CA-MSC tumors showed a high number of Monocytes and macrophages over-expressing Ccr2 and Tgfbi when compared to anti-PD-L1 responsive 2F8cis tumors. Our results also indicated that IPI-926 restored response to anti-PD-L1 therapy decresing the expression of Ccr2 and Tgfbi both in monocytes and macrophages. Our study represents the first detailed analysis generated by RNA-seq technology of 2F8cis/CA-MSC+ enriched tumor transcriptomes, treated with anti-PDL1 alone or in combination with HHi, and compared with anti-PDL1-treated tumors. The optimized data analysis workflows reported here should provide a framework for comparative investigations of expression profiles. Overall design: mRNA profiles of the following groups: a) a-PDL1-treated 2F8cis tumors , b) anti-PDL1-treated 2F8cis/CA-MSC tumors, and c) anti-PDL1+HHi-treated 2F8cis/CA-MSC tumors.