TLR2 and neoplasm: Of note, the compartment-specific regulation of a number of genes exhibiting opposite regulation in tumor epithelium or stroma would have been missed based on bulk data: genes that are up-regulated in tumor stroma and down-regulated in tumor epithelium are enriched for cytokine secretion and Toll-like receptor 2 signaling, suggesting that the microenvironment produces different sets of cytokines than the tumor itself, possibly reflecting different chemoattraction and hence different immune cell proportions depending on tumor proximity.