Basigin (BSG)

Extracellular matrix metalloproteinase inducer (EMMPRIN) (Biswas C. et al., 1995)
Tumor cell collagenase stimulating factor (TCSF) (Biswas C. et al., 1995)
CD147

Gene: BSG maps to 19p13.3 (Kaname T. et al., 1993).
mRNA: size:
Protein: a heavily glycosylated and broadly expressed member of the immunoglobulin superfamily. It contains two immunoglobulin superfamily domains. It has been shown to stimulate in vitro the fibroblast production of various MMPs such as MMP1, MMP2, MMP3.

Cell lines:
- CD147 (Basigin, EMMPRIN) is enriched oon the surface of tumor cells and is known to stimulate the production of MMPs by adjacent stromal cells. It has been found that CD147 engages in a homophilic interaction, predominantly through the first immunoglobulin domain. Anti-CD147 antibody 8G6 and recombinant CD147-Fc fusion protein markedly inhibited not only homophilic interaction, but also the production of secreted MMP-2 by MDA-MB-435 BCC and the MMP-2-dependent invasion of MDA-MB-435 cells through reconstituted basement-membrane Matrigel. Purified native CD147 induced the production of secreted MMP not only by dermal fibroblasts (MMP-1) but also by MDA-MB-435 cells themselves (MMP-2), suggesting homophilic CD147-binding may occur in the context of both heterotypic and homotypic cell-cell interactions. Purified deglycosylated CD147 failed to induce MMP-1 or MMP-2, but instead antagonized the MMP-1-inducing activity of purified native CD147 (Sun J. and Hemler M.E., 2001).

Tumors:
- The expression of BSG mRNAs was studieed in vivo, using in situ hybridization and Northern blotting analysis, in seven normal tissues and in 22 squamous cell carcinomas of the lung, and in seven benign proliferations and in 22 ductal carcinomas of the mammary gland. By in situ hybridization, BSG mRNAs were detected in 40 of 44 carcinomas, in pre-invasive and invasive cancer cells of both lung and breast cancers. BSG mRNAs and MMP2 mRNAs were both visualized in the same areas in serial sections in breast cancers, and were expressed by different cells, tumor cells, and fibroblasts. The histological results were confirmed by Northern blot analysis, which showed a higher expression of BSG mRNAs in cancers than in benign and normal tissues (Polette M. et al., 1997).

- The BSG protein was detected by immunoohistochemistry prominently in malignant proliferations of the breast and the lung. It was present at the surface of both tumor epithelial and peritumor stromal cells. Because previous studies have reported that stromal cells do not express BSG mRNAs, it is very likely that BSG is bound to stromal cells via a specific receptor. Moreover, it was demonstrated that the same peritumor stromal cells strongly expressed MMP2 (Caudroy S. et al., 1999).

- EMMPRIN (CD147, basigin) is thought too stimulate fibroblasts to produce the zymogen pro-MMP-2. The membrane type 1-matrix metalloproteinase (MT1-MMP, MMP14) is thought to assist in tumor invasion and metastasis by activating pro-MMP-2. The mRNA expression pattern of MT1-MMP, MMP-2, and EMMPRIN was studied in 18 breast tumor samples by in situ hybridization. MMP-2, MT1-MMP, and EMMPRIN mRNA expression were detected in all of the carcinomas. The MMP-2 mRNA expression was mainly localized to stromal cells at moderate to high levels surrounding the invading carcinoma cells but was also seen in single cells at low levels in in situ lesions and in some normal glandular cells. MT1-MMP and EMMPRIN were expressed in all of the carcinomas and were mainly localized to tumor cells; but they were also seen to some extent in single cells at low levels in in situ lesions and in normal glandular cells. No differences in levels of expression for MMP-2, MT1-MMP, or EMMPRIN were seen in patients who survived compared to patients who died from metastatic disease (Dalberg K. et al., 2000).

Biswas C. et al. (1995) The human tumour-cell derived collagenase stimulatory factor (renamed Emmprin) is a member of the immunoglobulin superfamily. Cancer Res. 55, 434-439. (PubMed)
Caudroy S. et al. (1999) Expression of the extracellular matrix metalloproteinase inducer (EMMPRIN) and the matrix metalloproteinase-2 in bronchopulmonary and breast lesions. J. Histochem. Cytochem. 47, 1575-1580. (PubMed)
Dalberg K. et al. (2000) Gelatinase A, membrane type 1 matrix metalloproteinase, and extracellular matrix metalloproteinase inducer mRNA expression: correlation with invasive growth of breast cancer. World J. Surg. 24, 334-340. (PubMed)
Guo H.M. et al. (1997) Stimulation of matrix metalloproteinase production by recombinant extracellular matrix inducer from transfected Chinese hamster ovary cells. J. Biol. Chem 272, 24-27. (PubMed)
Kaname T. et al. (1993) Mapping basigin (BSG), a member of the immunoglobulin superfamily, to 19p13.3. Cytogenet. Cell Genet. 64, 195-197. (PubMed)
Polette M. et al. (1997) Tumor collagenase stimulatory factor (TCSF) expression and localization in human lung and breast cancers. J. Histochem. Cytochem. 45, 703-709. (PubMed)
Sun J. and Hemler M.E. (2001) Regulation of MMP-1 and MMP-2 production through CD147/extracellular matrix metalloproteinase inducer interactions. Cancer Res. 61, 2276-2281. (PubMed)

Genome Database data (GDB Access Number: 228978)
GeneCard data (BSG)
UniGene data (Hs.74631)
OMIM data (ID = 109480)
LocusLink data (LocusID = 682)
Swiss-Prot (ID = P35613)


MMPs, TIMPs