H. Tanimoto et al., The stratum corneum chymotryptic enzyme that mediates shedding and desquamation of skin cells is highly overexpressed in ovarian tumor cells, CANCER, 86(10), 1999, pp. 2074-2082
BAGKGROUND. Proteases play essential roles in the process of tumor invasion
and metastasis. The serine protease stratum corneum chymotryptic enzyme (S
CCE) has been purified from human stratum corneum and is known to contribut
e to the cell shedding process by catalyzing the degradation of intercellul
ar cohesive structures at the skin surface. The presence of SCCE on the sur
face of tumor cells suggests it also may contribute to the process of tumor
cell shedding, resulting in early metastasis of carcinoma.
METHODS. Gene expression of SCCE was investigated in 44 ovarian tumors (12
low malignant potential tumors and 32 carcinomas) and 10 normal ovaries by
quantitative polymerase chain reaction (PCR). The PCR product was labeled w
ith P-32 and a phosphoimager was used to determine the relative expression
of SCCE compared with an internal control B-tubulin. mRNA transcripts were
studied by Northern blot hybridization and protein expression and localizat
ion was examined by Western blot analysis and immunohistochemistry.
RESULTS. mRNA expression levels of SCCE were elevated significantly in 66.7
% of 12 low malignant potential tumors and 78.1% of 32 carcinomas. Furtherm
ore, SCCE protein was abundant in tumor cells and tumor cell lines that ove
rexpressed the mRNA transcript.
CONCLUSIONS. The results of the current study suggest that SCCE frequently
is overexpressed in ovarian tumors and therefore may contribute to tumor ce
ll growth, tumor spread, and the metastatic potential of ovarian tumor cell
s. Cancer 1999;86:2074-82. (C) 1999 American Cancer Society.