Expression of matrix metalloproteinase-26 in multiple human cancer tissues and smooth muscle cells.

Background and objective: Elevated expression of matrix metalloproteinases (MMPs) has been found in multiple carcinoma tissues. MMP-26 is highly expressed in prostate and breast cancer tissues, and promotes the invasion of human prostate cancer cells not only through the cleavage of fibronectin and type IV collagen but also by the activation of pro-MMP-9, a powerful gelatinase. This study was to present a comprehensive protein expression profile of MMP-26 in multiple human cancer tissues.

Methods: The protein expression pattern of MMP-26 was examined using immunohistochemistry and multiple-tissue microarray. MMP-26 mRNA expression in coronary artery smooth muscle cells was detected by reverse transcription-polymerase chain reaction (RT-PCR).

Results: The expression of MMP-26 in breast, colon, lung, brain, head and neck, prostate cancer, and melanoma tissues was significantly elevated when compared with parallel normal tissues (P<0.05), while not significantly elevated in kidney cancer, ovarian cancer, and non-Hodgkin's lymphoma (P>0.05). MMP-26 was also detected to express in gastric, rectal, thyroid, esophageal, and pancreatic cancers. MMP-26 protein was expressed in smooth muscle cells of the prostate and associated blood vessels. MMP-26 mRNA was also detected to express in human coronary artery smooth muscle cells.

Conclusions: MMP-26 expression may be associated with multiple human carcinomas, and it may serve as a molecular marker for the early diagnosis of these carcinomas. MMP-26 may also contribute to smooth muscle function in the human prostate and cardiovascular system.