As the primary factors for the reduced anticancer effect 1) the reduced delivery and uptake of the anticancer agent, 2) the need for the conversion of molecular oxygen (O 2 ) into reactive oxygen species (ROS), 3) the preferred therapeutic effect against highly proliferating cells, which is reduced under hypoxic conditions, or 4) adaptation of the cancer cells by promoting cell survival and upregulating certain resistance pathways, has been suggested 1,2,3,4,5
This in turn, first activates the PI3K/Akt/mTOR, PI3K/Akt/FoxO, or Ras/MAPK/(ERK-1/2) pathways that have important roles in cancer cell growth and carcinogenesis
Citrus fruits Orange fruits contain high amounts of vitamin C, which can be used to maintain glutathione levels
Despite promising preliminary findings, these compounds are generally associated with a poor spatial and temporal control of the treatment as well as poor cancer selectivity, resulting in potential side effects and non-ideal drug doses