Nanotechnology is a rapidly growing field of science that has a considerable impact on many branches of medicine. Nanoparticles are developing at a rapid pace due to their effect which is achieved by combining them with drugs as well as their increased importance in the drug delivery system. Synthesis of chitosan nanoparticles by ionic gelation is becoming increasingly important due to its low cost and environmentally friendly approach. This preliminary study was the first one to investigate the cytotoxic effect of chitosan nanoparticles with combination of Leonotis nepetifolia (L.) R.Br. transformed root extract against cervical cancer (HeLa), breast cancer (MCF-7), glioma cancer (MO59J) cell lines and normal human fibroblast (Hs68) cell line. Besides, a preliminary analysis of apoptosis induced by caspase 3/7, microscopic observations of morphology changes and apoptosisrelated genes expression in cancer cells have been showed. According to MTT results, the synthesized chitosan nanoparticles in combination with Leonotis nepetifolia normal and transformed root extracts showed a stronger cytotoxic effect on all tested cancer lines (HeLa, MCF-7 and MO59J), compared with the nanoparticles and the extracts alone, with IC 50 = 0.608, 0.306, 0.112 mg/mL, respectively. In contrast, no cytotoxic effect was shown against the human fibroblast (Hs68) line in the tested concentration range. Preliminary induction of apoptosis showed changes in cell morphology, genes expression and caspase 3/7 activation after treatment with chitosan nanoparticles in combination with normal and transformed from Leonotis nepetifolia root extracts. These discoveries have positive implications for further studies on development of nanoparticles in anti-cancer therapy. The key objective of this work is to test the anti-cancer potential of L. nepetifolia transformed root extract obtained by agrotransformation in combination with natural chitosan nanoparticles as a component capable of enhancing the effect of the extract against various in vitro models.