Antibiotics are considered the cornerstone of modern medicine; however, currently, antibiotic resistance has become a global health issue.
Antibiotics also find new uses in the treatment of other pathologies as well as
cancer. The present study aimed to verify the impact of
tetracycline and
ampicillin in a colorectal
adenocarcinoma cell line, HT-29. The effects of the two
antibiotics on cell viability and nucleus were evaluated by the means of MTT assay and the Hoechst staining method, respectively. The
irritant potential at vascular level of the chorioallantoic membrane was tested by the HET-CAM assay. Treatment of HT-29 cells with the two
antibiotics determined different effects: (i)
tetracycline induced a dose- and time-dependent cytotoxic effect characterized by decreased cell viability, changes in cells morphology, apoptotic features (nuclear fragmentation), and inhibition of cellular migration, whereas (ii)
ampicillin exerted a biphasic response-cytotoxic at low doses and proliferative at high concentrations. In terms of effect on blood vessels, both
antibiotics exerted a mild
irritant effect. These results are promising and could be considered as starting point for further in vitro studies to define the molecular mechanisms involved in the cytotoxic/proliferative effects.