Ocimum basilicum L. (basil) presents pro-apoptotic activity in an Ehrlich's experimental tumor murine model

This study aimed to evaluate the therapeutic effect of an ethanol extract of Ocimum basilicum L. (EEOb) aerial parts against Ehrlich's experimental tumor (EET) in mice. Swiss mice were divided into two groups (control and treated; n = 6). On day 21, all mice were inoculated subcutaneously with 2 × 106 (0.05 mL) EET cells in the left paw for solid tumor development. This study lasted 28 days. Treatment began 24 hours after inoculation with EET. Measurements of dorsoplantar thickness were used to assess tumor growth. The paw pad was collected for histopathological analysis and stained using the argyrophilic nucleolar organizing regions (AgNOR) technique and immunohistochemistry for proliferating cell nuclear antigen, Bcl-2 and Bax. The treatment of animals with EEOb at 100 mg/kg intraperitoneally was able to reduce the growth (Control = 3.7 ± 0.1 mm vs. EEOb = 5.7 ± 0.2 mm) and the number of AgNORs of solid Ehrlich tumor. The antitumor effect of EEOb was associated with the induction of apoptosis of tumoral cell, as suggested by the reduction of the content of Bcl-2 induced by extract. The study demonstrated that daily administration of EEOb is able to reduce the growth of EET by induce apoptosis of tumoral cells.