Thrombospondin II
(TSP2, TSP-2)

THBS2 (gene locus)

Gene: THBS2 maps to 6q27 (LaBell T.L. et al., 1992).
mRNA: size: 7.5 kb (LaBell T.L. et al., 1992).
Protein: sequence comparison of THBS1 and THBS2 demonstrates that the 2 cysteines involved in interchain disulfide linkage and trimer assembly are conserved in both. Swiss 3T3 fibroblasts and epithelial cells transfected with THBS expression vectors express both homotrimeric and heterotrimeric forms of the protein (O'Rourke K.M. et al., 1992).

Cell lines:

Tumors:
- Using RT-PCR, it was found that TSP2, like TSP1, was expressed in human breast tissues, and that TSP1 and TSP2 mRNA expression in invasive breast carcinoma not otherwise specified (NOS) was significantly increased compared to that observed in normal and benign tissues. The expression of TSP1 and TSP2 in invasive breast ductal carcinoma NOS did not significantly correlate with any of the prognostic factors studied (tumor size, lymph node status, morphology, and hormone receptor status). However, when the study population was divided according to the quantity of tumor stroma, TSP1 (and possibly TSP2) mRNA expression and microvessel counts in desmoplastic-rich stroma of breast carcinoma NOS were significantly increased compared to those observed in desmoplastic-poor stroma (Bertin N. et al., 1997).

Bertin N. et al. (1997) Thrombospondin-1 and -2 messenger RNA expression in normal, benign, and neoplastic human breast tissues: correlation with prognostic factors, tumor angiogenesis, and fibroblastic desmoplasia. Cancer Res. 57, 396-399.
LaBell T.L. et al. (1992) Thrombospondin II: partial cDNA sequence, chromosome location,and expression of a second member of the thrombospondin gene family in humans. Genomics 12, 421-429.
O'Rourke K.M. et al. (1992) Thrombospondin 1 and thrombospondin 2 are expressed as both homo- and heterotrimers. J. Biol. Chem. 267, 24921-24924.