title: A possible role for perforin and granzyme B in resveratrol-enhanced radiosensitivity of prostate cancer.
abstract: Perforin and granzyme B are expressed primarily by activated lymphocytes  (cytotoxic T cells, natural killer cells, and natural killer T cells) and  function together to induce apoptosis of target cells. Typically, these  proteins are not expressed in tumor cells. In the present study, we  established the constitutive expression of perforin and granzyme B by the PC-3  and DU145 prostate cancer (PCA) cell lines with reverse transcription  polymerase chain reaction, immunohistochemistry, Western blot, or a  combination of techniques. The combination of radiation and resveratrol  (XRT/RSV) additively/synergistically decreased survival of PCA because, at  least in part, of increased apoptosis. We further demonstrated that treatment  with RSV up-regulated the expression of both perforin and granzyme B, whereas  treatment with XRT up-regulated the expression of granzyme B, but not that of  perforin. Combined XRT/RSV treatment of PCA cells further increased the  expression of both perforin and granzyme B compared with RSV or XRT alone.  Thus, increased radiosensitivity of prostate cancer cells induced by RSV  correlated with up-regulation of perforin and granzyme B, demonstrating a  possible mechanism for tumor apoptosis. These findings might be helpful in  devising new strategies for treating PCA.
authors.affiliation: Department of Surgery, Ellis Fischel Cancer Center, University of Missouri School of Medicine, M316, Medical Sciences Building, Columbia, MO 65212, USA. fangy@health.missouri.edu
authors.forename: Yujiang
authors.initials: Y
authors.lastname: Fang
authors.forename: Elizabeth J
authors.initials: EJ
authors.lastname: Herrick
authors.forename: Michael B
authors.initials: MB
authors.lastname: Nicholl
mesh_terms: D017209:Apoptosis / Q000187:drug effects; D045744:Cell Line, Tumor; D053804:Granzymes / Q000502:physiology*; D006801:Humans; D008297:Male; D054353:Perforin / Q000502:physiology*; D011471:Prostatic Neoplasms / Q000188:drug therapy* / Q000532:radiotherapy*; D011836:Radiation Tolerance / Q000187:drug effects*; D000077185:Resveratrol; D013267:Stilbenes / Q000627:therapeutic use
chemical_list: D013267:Stilbenes; D054353:Perforin; D053804:Granzymes; D000077185:Resveratrol