As part of our ongoing studies to characterize molecular alterations in a well-defined series of surgically resected esophageal cancers, we examined the expression of 2 ras-regulated genes, whose products (osteopontin and cathepsin L) previously were shown to be associated with tumor invasion and metastasis.
This study provides the first evidence that variation at nt -443 in the OPN promoter increases the potential for gastric cancer metastasis and subsequent death in the Chinese population.
For each 50 units increment of serum OPN, an increased risk of metastasis by 69 % (unadjusted HR 1.69, 95 % CI 1.12-2.56, p = 0.01) and an increased risk of death by 95 % (unadjusted HR 1.95, 95 % CI 1.15-3.32, p = 0.01) were observed.
We investigated the possible mechanisms of osteopontin splicing variant and its role in EMT and cancer metastasis using NSCLC cell line and cell and molecular biology techniques.
The expression patterns and functional roles of three osteopontin splice variants (OPNa, b, and c) in cancer metastasis and progression are not well understood due to the lack of reliable assays to differentiate the isoforms.
Molecular factors involved in the process of HCC invasion and metastasis, including adhesion molecules (E-cadherin, catenins, ICAM-1, laminin-5, CD44 variants, osteopontin), proteinases responsible for the degradation of extracellular matrix (MMPs, uPA system), as well as angiogenesis regulators (such as VEGF, intratumor MVD), have also been shown to be potential predictors for HCC metastatic recurrence and clinical outcomes.
Although basal transcription repression was impaired and the pro-metastatic protein osteopontin was differentially down-regulated by BRMS1(L174D) and BRMS1(DeltaCC1), both down-regulated the epidermal growth factor receptor and suppressed metastasis in MDA-MB-231 and -435 breast cancer xenograft models.
Expression of S100P, S100A4, osteopontin (OPN) or anterior gradient homologue 2 (AGR2) proteins can induce metastasis but fail to induce tumorigenesis per se.
Taken together, our study demonstrates that OPN contributes to the ovarian cancer cell proliferation and metastasis, which is activated by TLR4 signaling pathway.
The following review will discuss the molecular structure of OPN, the evidence for its functional role in tumor cell metastasis, the downstream signals that activate invasive mechanisms, and the recent reports concerning regulation of OPN transcription.
TW01 and Hone1 NPC cells with overexpression FLJ10540 or siRNA to repress endogenous FLJ10540 were generated by stable transfection to further elucidate the molecular mechanisms of FLJ10540-elicited cell growth and metastasis under osteopontin stimulation.
Notably, inhibition of fibroblast osteopontin with low doses of a novel small molecule prevents lung metastasis in a mouse model of human breast cancer metastasis.
As confirmed at the mRNA and protein levels in both MDA-MB-231 and MDA-MB-468 cells, expression of the NF-κB regulator IKKα was significantly reduced, along with several NF-κB targets with known roles in metastasis (OPN, MMP9, uPA, SPARC, IL11, and IL1β).
This study investigated the influence of sevoflurane on the response of lung and renal cancer cells to cisplatin, with focus on transforming growth factor-beta (TGF-β) and osteopontin (OPN) that are both closely associated with cancer tumorigenesis and metastasis.
Promotion of metastasis in response to miR-224 downregulation was associated with derepression of the stroma-associated RKIP target genes, CXCR4, MMP1, and OPN, which are involved in breast tumor metastasis to the bone.
However metastasis-suppressed MDA-MB-435 cells, which were transfected with breast cancer metastasis suppressor 1 (BRMS1), expressed significantly less OPN.
Osteopontin (OPN) is an integrin-binding protein that has been shown to be associated with the progression of several cancer types, and to play an important functional role in various aspects of malignancy, particularly tissue invasion and metastasis.