title: Vincristine modulates the expression of Ki67 and apoptosis in naturally occurring canine transmissible venereal tumor (TVT).
abstract: We investigated eight adult dogs that were brought to veterinary clinics with a history of transmissible venereal tumors (TVT). Our goal was to demonstrate the occurrence of apoptosis and the cessation of cell proliferation at every phase of scheduled chemotherapy for naturally occurring TVT. Tissue samples were collected immediately after weekly treatments with vincristine sulfate and processed for histological purposes. Sections 5 μm thick were stained by the TUNEL reaction for apoptosis and immunostained for Ki67 as a proliferation marker. We observed that after vincristine applications, tumor cell proliferation ceased and apoptosis increased. Ki67 HSCORE values were significantly lowered after the first and second treatments with the chemotherapeutic agent compared to controls, whereas TUNEL HSCORE values were significantly higher after two applications of vincristine compared to controls. Our results suggest that scheduled vincristine sulfate applications stabilize the induction of tumor regression by inducing apoptosis and preventing cell proliferation.
authors.affiliation: Department of Obstetrics and Gynecology, Faculty of Veterinary Medicine, Uludag University, Görükle, Bursa, Turkey.
authors.forename: G R
authors.initials: GR
authors.lastname: Özalp
authors.forename: B
authors.initials: B
authors.lastname: Zik
authors.forename: A
authors.initials: A
authors.lastname: Bastan
authors.forename: S
authors.initials: S
authors.lastname: Peker
authors.forename: E S
authors.initials: ES
authors.lastname: Özdemir-Salci
authors.forename: I
authors.initials: I
authors.lastname: Bastan
authors.forename: I
authors.initials: I
authors.lastname: Darbaz
authors.forename: S
authors.initials: S
authors.lastname: Salar
authors.forename: K
authors.initials: K
authors.lastname: Karakas
mesh_terms: D000818:Animals; D017209:Apoptosis / Q000187:drug effects; D004283:Dog Diseases / Q000188:drug therapy*; D004285:Dogs; D005260:Female; D005786:Gene Expression Regulation / Q000187:drug effects; D019394:Ki-67 Antigen / Q000378:metabolism*; D008297:Male; D050257:Tubulin Modulators / Q000494:pharmacology / Q000627:therapeutic use; D014685:Venereal Tumors, Veterinary / Q000188:drug therapy*; D014750:Vincristine / Q000494:pharmacology / Q000627:therapeutic use*
chemical_list: D019394:Ki-67 Antigen; D050257:Tubulin Modulators; D014750:Vincristine