title: Capsaicin-induced apoptosis and reduced release of reactive oxygen species in MBT-2 murine bladder tumor cells.
abstract: Bladder cancer is a common cancer with high risk of recurrence and mortality. Intravesicle chemotherapy after trans-urethral resection is required to prevent tumor recurrence and progression. It has been known that antioxidants enhance the antitumor effect of bacillus Calmette-Guerin (BCG), the most effective intravesical bladder cancer treatment. Capsaicin, the major pungent ingredient in genus Capsicum, has recently been tried as an intravesical drug for overactive bladder and it has also been shown to induce apoptotic cell death in many cancer cells. In this study, we investigated the apoptosis-inducing effect and alterations in the cellular redox state of capsaicin in MBT-2 murine bladder tumor cells. Capsaicin induced apoptotic MBT-2 cell death in a time- and dose-dependent manner. The capsaicin-induced apoptosis was blocked by the pretreatment with Z-VAD-fmk, a broad-range caspase inhibitor, or Ac-DEVD-CHO, a caspase-3 inhibitor. In addition to the caspase-3 activation, capsaicin also induced cytochrome c release and decrease in Bcl-2 protein expression with no changes in the level of Bax. Furthermore, capsaicin at the concentration of inducing apoptosis also markedly reduced the level of reactive oxygen species and lipid peroxidation, implying that capsaicin may enhance the antitumor effect of BCG in bladder cancer treatment. These results further suggest that capsaicin may be a valuable intravesical chemotherapeutic agent for bladder cancers.
authors.affiliation: College of Pharmacy, Yeungnam University, Gyongsan 712-749, Korea.
authors.forename: Ji-Seon
authors.initials: JS
authors.lastname: Lee
authors.forename: Jong-Sun
authors.initials: JS
authors.lastname: Chang
authors.forename: Ji Youl
authors.initials: JY
authors.lastname: Lee
authors.forename: Jung-Ae
authors.initials: JA
authors.lastname: Kim
mesh_terms: D000590:Amino Acid Chloromethyl Ketones / Q000494:pharmacology; D000818:Animals; D017209:Apoptosis / Q000187:drug effects*; D015153:Blotting, Western; D002211:Capsaicin / Q000494:pharmacology*; D053148:Caspase 3; D061945:Caspase Inhibitors; D020169:Caspases / Q000378:metabolism; D045744:Cell Line, Tumor; D015853:Cysteine Proteinase Inhibitors / Q000494:pharmacology; D045304:Cytochromes c / Q000378:metabolism; D003600:Cytosol / Q000187:drug effects / Q000378:metabolism; D053938:DNA Fragmentation / Q000187:drug effects; D004587:Electrophoresis, Agar Gel; D004789:Enzyme Activation / Q000187:drug effects; D005434:Flow Cytometry; D051379:Mice; D008928:Mitochondria / Q000187:drug effects / Q000378:metabolism; D009842:Oligopeptides / Q000494:pharmacology; D019253:Proto-Oncogene Proteins c-bcl-2 / Q000378:metabolism; D017382:Reactive Oxygen Species / Q000378:metabolism*; D013997:Time Factors; D001749:Urinary Bladder Neoplasms / Q000378:metabolism / Q000473:pathology; D051028:bcl-2-Associated X Protein
chemical_list: D000590:Amino Acid Chloromethyl Ketones; C494827:Bax protein, mouse; D061945:Caspase Inhibitors; D015853:Cysteine Proteinase Inhibitors; D009842:Oligopeptides; D019253:Proto-Oncogene Proteins c-bcl-2; D017382:Reactive Oxygen Species; C108637:aspartyl-glutamyl-valyl-aspartal; D051028:bcl-2-Associated X Protein; C096713:benzyloxycarbonylvalyl-alanyl-aspartyl fluoromethyl ketone; D045304:Cytochromes c; C505409:Casp3 protein, mouse; D053148:Caspase 3; D020169:Caspases; D002211:Capsaicin