Use of a colorimetric assay to evaluate the proliferation of canine mammary tumor cells exposed to propofol.

Drugs applied on human cancer cells can influence the rate of cell proliferation. The present study investigates the use of the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrasodium bromide (MTT) colorimetric assay to evaluate canine tumor cell proliferation after exposure to the injectable anesthetic, propofol. Primary (CIPp) and metastatic (CIPm) canine tubular adenocarcinoma cell lines were incubated with cell culture medium (control) or propofol (1, 5, and 10 µg/mL). The MTT assays were performed after 6 and 12 hours of exposure. Measurements of absorbance were obtained for each condition with a spectrophotometer and compared with controls using a 3-way analysis of variance (P < 0.05). An increased cell proliferation rate was observed in CIPp exposed to 5 and 10 µg/mL of propofol for 6 hours and 1, 5, and 10 µg/mL for 12 hours. No significant changes were observed in CIPm after 6 hours of exposure. All propofol concentrations decreased the cell proliferation rate in CIPm after 12 hours of exposure. The MTT assays showed that exposure of CIPp to propofol for 6 and 12 hours increased cell proliferation. A decrease in the CIPm proliferation rate was observed when propofol exposure lasted for 12 hours. Further studies are warranted to better understand the role of propofol on cancer cell proliferation.

Les médicaments appliqués sur les cellules cancéreuses humaines peuvent influencer la vitesse de prolifération cellulaire. La présente étude a examiné l'utilisation du test colorimétrique au bromure de 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tétrasodique (MTT) pour évaluer la prolifération de cellules tumorales canines après exposition à l'anesthésique injectable, propofol.Des lignées cellulaires primaires (CIPp) et métastasiques (CIPm) d'adénocarcinome tubulaire canin furent incubées avec du milieu de culture cellulaire (témoin) ou du propofol (1, 5, et 10 µg/mL). Les tests au MTT ont été effectués après 6 et 12 h d'exposition. Les mesures d'absorbance furent obtenues pour chaque condition à l'aide d'un spectrophotomètre et comparées aux témoins en utilisant une analyse de variance à trois facteurs (P < 0,05).Une augmentation de la vitesse de prolifération cellulaire fut observée chez les CIPp exposées à 5 et 10 µg/mL de propofol pour 6 h et à 1, 5, et 10 µg/mL pour 12 h. Aucun changement significatif ne fut observé chez les CIPm après 6 h d'exposition. Toutes les concentrations de propofol ont réduit la vitesse de prolifération cellulaire des CIPm après 12 h d'exposition.Les tests au MTT ont démontré que l'exposition de CIPp au propofol pour 6 et 12 h augmentait la prolifération cellulaire. Une réduction de la vitesse de prolifération des CIPm fut observée lorsque l'exposition au propofol durait 12 h. Des études supplémentaires sont nécessaires pour mieux comprendre le rôle du propofol sur la prolifération des cellules cancéreuses.(Traduit par Docteur Serge Messier).

Canine mammary tumour cells exposure to sevoflurane: effects on cell proliferation and neuroepithelial transforming gene 1 expression.

OBJECTIVE: The influence of perioperative factors, such as anaesthetic and analgesic techniques, on metastatic spread following surgery for primary cancer removal is of growing interest. The present study investigated the effects of sevoflurane on canine mammary tumour cell proliferation (MTT colorimetric assay) and on the expression of neuroepithelial transforming gene 1 (NET1). STUDY DESIGN: Prospective controlled in vitro trial. STUDY MATERIAL: Primary (CIPp) and metastatic canine tubular adenocarcinoma (CIPm) cells. METHODS: To perform MTT tests, cell lines were seeded at a density of 3000 cells per well and incubated with sevoflurane (1, 2.5 or 4 mM) or only with the culture medium (control). Sevoflurane was added to the cell cultures every hour to avoid changes in drug concentration. MTT assays were performed after 6 hours of exposure obtaining absolute values of absorbance. The RNA isolated from the lysates of the same cell lines underwent quantitative polymerase chain reaction to evaluate NET1 gene expression changes compared with controls. One- or two-way analysis of variance was used as appropriate (p < 0.05). RESULTS: A significant increase in cell proliferation compared with controls was observed in CIPp treated with lower sevoflurane concentrations, whereas a significant decrease in cell proliferation was found in CIPm treated with all the sevoflurane concentrations. All CIPp treatments did not induce changes in gene expression compared with controls, whereas a significant increase in gene expression was observed in CIPm between controls and the higher sevoflurane concentration. CONCLUSIONS AND CLINICAL RELEVANCE: Sevoflurane treatments modified the cell proliferation rate in both cell lines showing an increase or decrease when applied to CIPp or CIPm, respectively. Expression of the NET1 gene increased after treatment with sevoflurane 4 mM in metastatic cells. The role of sevoflurane on cancer recurrence should be further investigated.