HIF1A and neoplasm: Mechanistic studies revealed that CLG depressed the levels of SDF-1α and CXCR4, as well as HIF-1α, MMP-2, VEGF, PI3K, Akt, P-PI3K and P-Akt, while elevated the level of collagen IV, in the transplanted tumor of the nude mice, pointing to the involvement of HIF-1α/SDF-1α-CXCR4/PI3K-Akt signaling pathway in the action of CLG, which result in the reduction of synthesis and release of VEGF, and decreased degradation of collagen IV by MMP-2.