CXCL12 and cancer: The coordinate axis of cancer cells (lactate)/MCT1 (transformation from fibroblast to iCAF)/secretion of CXCL12 (promoting transcription by HIF1A)/Treg recruitment (CXCL12-ACKR3)/TGF-β1 secretion (tumor immune suppression microenvironment) was discovered by spatial transcriptomics and validated by immune fluorescence staining and bulk RNA-sequencing data of OSCC.