Collectively, the present studies demonstrate that Galectin-1-driven production of SDF-1 in PSCs through activation of NF-κB promotes metastasis in PDAC, offering a potential target in the treatment of pancreatic cancer.
Significantly higher levels of SDF-1 were seen in node-positive than in node-negative tumours (P = 0.05), in tumours that metastasized (P = 0.05), and tumours from patients who died (P = 0.03) than in tumours from patients who were disease free.
Our in vitro and in vivo data strongly indicate that pVHL coordinately regulates expression of metastasis-associated genes CXCR4/CXCL12 and MMP2/MMP9 but the exact molecular mechanism of this regulation remains to be determined.
In hematological malignancies and solid tumors, the overexpression of CXCR4 on the cell surface has been shown to be responsible for disease progression, increasing tumor cell survival and chemoresistance and metastasis to organs with high CXCL12 levels (e.g., lymph nodes and bone marrow (BM)).
There is also a significant correlation between the expression levels of CXCR4-CXCL12 axis and metastasis-related genes (E-cadherin and MMP2) in tumor samples with advanced stages of metastasis.
Although this study will need further in vivo validation, our observations suggest that (a) silencing of CXCL12 in cervical cancer cells may be critical in migration and invasion, the key events in cancer cell metastases; (b) cervical cancer cells having down regulated CXCL12 are more prone to being attracted to CXCL12 expressed at secondary sites of metastases; and (c) CXCL12 inhibits anchorage independent cell growth via anoikis.
<i>in-silico</i> analysis finds that CXCL12-CXCR4 is associated with an increased expression of PDZK1, PI3k and Akt which lead the breast tumor towards metastasis.
Recent studies suggest that SDF-1 and CXCR4 are expressed in certain cancer cells, and malignant cells use this chemokine/receptor system to promote tumor progression and metastasis.
Inhibition of MET expression or function leads to (i) a decreased expression of the early myogenic marker MyoD, (ii) a decreased ability of ARMS cells to metastasize to bone marrow cavities, (iii) downregulation of CXCR4 receptor expression and (iv) a decreased migration of MET-depleted cells towards gradients of HGF and SDF-1.
CXCR4 was more expressed in PT than in metastases (p = 0.0067), whereas CXCL12 was highly expressed in metastatic lesions located in liver and lung (p < 0.0001), as reported for human breast cancer.
Constitutive expression of CXCL12 in human colorectal carcinoma cells reduced orthotopic tumor formation and inhibited metastasis in severe combined immunodeficient mice.
It is possible that allele A carrier hormone receptor-positive patients could be more susceptible to metastasis development, since they present a lower CXCL12 expression in tumor tissue, and tumor cells expressing CXCR4 could migrate toward CXCL12 gradient.
Further study indicated that CXCL12 expression was positively correlated innate inflammation pathways such as NFκB and negatively correlated with metastasis, while EPHB3 had a reverse result.
The ability of Kp-10 to inhibit signaling and chemotaxis induced by SDF-1 indicates that activation of GPR54 signaling may negatively regulate the role of CXCR4 in programming tumor metastasis.
Our results show that AEG-1 activates the expression of the metastasis-associated chemokine receptor CXCR4, and that its ligand, CXCL12, is secreted by HPMECs.
For TNM stage III, high cytoplasmic expression of CXCL12 was associated with better 5-year DFS in both cohorts (P = 0.006 and P = 0.006, respectively).
Real- time PCR was used for analyzing the changes in the expression level of CXCL12 and CXCR4 as two important genes involved in migration and metastasis of breast cancer cells. l-arginine increased 5-FU effect on BT-20 and MCF-7 cell lines by reducing cell viability and increasing apoptosis and NO production.
We therefore hypothesized that tumors overexpressing the SDF-1 receptor CXCR4 have an enhanced ability to metastasize in patients with low plasma SDF-1 levels.