CXCR4 and neoplasm: On the 28th day after the operation, CRC growth and liver metastasis were assessed by morphology, the changes in the expression of HIF-1α (hypoxia inducible factor-1α), stromal cell–derived factor-1 alpha (SDF-1α), CXCR4 (C-X-C chemokine receptor type 4), PI3K, and Akt in the transplanted tumor and SDF-1α and CXCR4 in the liver were detected by Western blot and immunohistochemistry.