Maspin

Maspin is a protein related to the Serine Protease Inhibitor family. It is thought to be a tumour suppressor gene, inhibiting tumour formation angiogenesis and metastases. p53 regulates the expression of maspin.

Immunohistochemical expression

The protein can be variously detected in both cytoplasm and nucleus.

• Breast Maspin is expressed by normal breast epithelial cells. There is progressive loss of expression from in situ to invasive carcinoma. Myoepithelial cells stain more intensively than in the tumour cells. Nuclear staining in tumour cells correlates with ER and PR positivity and indices of good prognosis, while cytoplasmic staining shows an inverse relationship with ER and PR staining and indices of a poor prognosis.

• Oral carcinoma Maspin expression is associated with absence of lymph node metastases and improved survival

• Pancreas Maspin is not expressed by normal pancreatic tissue but is present in high grade pancreatic in situ neoplasia and pancreatic carcinoma (23 of 24 cases), with both nuclear and cytoplasmic staining3.

Diagnostic utility

• Maspin may be a useful marker for myoepithelial cells and may have prognostic significance in breast neoplasia: more data is needed on both subjects.

• Maspin may be useful in identifying pancreatic carcinoma: more data is needed.

References

1Mohsin, S. K., M. Zhang, et al. (2003). "Maspin expression in invasive breast cancer: association with other prognostic factors." J Pathol 199(4): 432-5.

2Xia, W., Y. K. Lau, et al. (2000). "High tumoral maspin expression is associated with improved survival of patients with oral squamous cell carcinoma." Oncogene 19(20): 2398-403.

3Maass, N., T. Hojo, et al. (2001). "Expression of the tumor suppressor gene Maspin in human pancreatic cancers." Clin Cancer Res 7(4): 812-7.

This page last revised 13.9.2004.

©SMUHT/PW Bishop