Although we have focused on PDAC in this review, mounting evidence suggests that CXCL12 is an important driver of metastasis, immune evasion, and chemoresistance in other solid tumors, including HNSCC [97,98], urothelial cancer [99], and ovarian and breast carcinomas [100,101,102], so it is possible that tipifarnib could find a therapeutic niche across a broad range of CXCL12-associated tumors. This evidence concerns the gene CXCL12 and breast carcinoma.