Open AccessIntratumoral recombinant human interferon alpha‐2a and vincristine combination therapy in canine transmissible venereal tumour
Author(s) -
Kanca Halit,
Tez Gizem,
Bal Kazim,
Ozen Dogukan,
Alcigir Eray,
Atalay Vural Sevil
Publication year - 2018
Publication title -
veterinary medicine and science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.485
H-Index - 11
ISSN - 2053-1095
DOI - 10.1002/vms3.119
Subject(s) - vincristine , medicine , chemotherapy , gastroenterology , immunology , oncology , cyclophosphamide
Canine transmissible venereal tumour ( CTVT ) is a naturally occurring contagious neoplasm of dogs located mainly on the external genitalia of both sexes. The course of vincristine chemotherapy, the most effective and practical therapy, is affected by the immune status of the host. The aim was to investigate recombinant human interferon alpha‐2a (rh IFN α ‐2a) and vincristine for treatment of CTVT . A total of 21 female dogs were included. In group I ( n = 9), vincristine (0.025 mg/kg, IV ) was administered weekly. In group II ( n = 6), dogs were injected intratumorally weekly with 1.5 million IU rh IFN α ‐2a. In group III ( n = 6), rh IFN α ‐2a and vincristine were combined. No tumour regression was observed after three injections of rh IFN α ‐2a in group II and weekly vincristine was administered. The number of tumour infiltrating lymphocytes ( TIL s), mitotic figures and apoptotic cells were counted in subsequent incisional tumour biopsies. The Kaplan–Meier Method was used to analyse survival using complete tumour regression as the outcome and Breslow Test was used for comparison of survival curves. Differences in TIL s, cell proliferation and apoptosis between groups were assessed by analysis of covariance. Complete regression was observed in all animals included. Mean duration of vincristine treatment for complete regression was shorter in group II (3.50 weeks, 95% CI , 3.06–3.94, P < 0.05) and group III (3.17 weeks, 95% CI , 2.84–3.49, P < 0.01) compared to group I (5.11 weeks, 95% CI , 4.42–5.80). Vincristine and rh IFN α ‐2a combination increased TIL s in CTVT biopsies compared to vincristine treatment ( P = 0.017) and vincristine treatment after rh IFN α ‐2a ( P = 0.049). Vincristine treatment after rh IFN α ‐2a (Group II ; P < 0.001) and rh IFN α ‐2a and vincristine combination (Group III ; P < 0.001) decreased apoptosis. The results indicate that intratumoral rh IFN α ‐2a treatment alone is not effective in CTVT . However, combination of rh IFN α ‐2a and vincristine shortens the duration of treatment compared to vincristine therapy.