Studies From University Of Wisconsin Reveal New Findings On Non-Melanoma Skin Cancer

"Polo-like kinase 1 (Plk1) is becoming an increasingly attractive target for cancer management. Plk1 has been shown to be overexpressed in a variety of cancers; however its role in skin cancers is not well-understood," scientists in the United States report.

"We recently demonstrated that Plk1 is overexpressed in human melanoma and gene-knockdown as well as chemical-inhibition of Plk1 resulted in a significant decrease in melanoma cell viability and growth without affecting the growth of the normal human epidermal melanocytes (NHEMs). Further, the observed anti-proliferative response of Plk1 was found to be accompanied with a significant G(2)/M cell cycle arrest, mitotic catastrophe and induction of apoptosis in melanoma cells. In this study, we determined the expression profile of Plk1 in non-melanoma skin cancers viz. basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). Our data demonstrated that like melanoma, Plk1 is significantly overexpressed in BCC and SCC samples. Further, we also found that compared to normal human epidermal keratinocytes (NHEKs), Plk1 was overexpressed at both the protein and mRNA levels in squamous A253 and A431 cells. In addition, a similar protein expression pattern was found for the downstream targets of Plk1, viz. Cdk1, Cyclin B1 and Cdc25C," wrote T.L. Schmit and colleagues, University of Wisconsin.

The researchers concluded: "We believe that the expression pattern of Plk1 in the various skin cancers, the observed insusceptibility of normal cells to Plk1 inhibition and the easy accessibility for topical applications lends the skin as an attractive tissue for Plk1 based cancer chemoprevention and chemotherapeutic applications."

Schmit and colleagues published their study in Cell Cycle (Polo-like kinase 1 (Plk1) in non-melanoma skin cancers. Cell Cycle, 2009;8(17):2697-2702).

For additional information, contact N. Ahmad, University of Wisconsin, Dept. of Dermatology, B-25 Med Science Center, 1300 University Avenue, Madison, WI 53706, USA.

The publisher's contact information for the journal Cell Cycle is: Landes Bioscience, 1002 West Avenue, 2ND Floor, Austin, TX 78701, USA.

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