Hepatocellular carcinoma (HCC) is considered a major problem worldwide. It is the fifth most common cancer and the second cause of cancer death worldwide (Wen et al., 2022). Chemotherapy is the main treatment of cancer but it is associated with dangerous side-effects and cancer resistance. Recently, fundamental efforts have been exerted to find a new therapeutic options for cancerous diseases (Rashed et al., 2020; Arrigoni et al., 2022).

Epirubicin is a well-known chemotherapeutic drug which classified as an anthracyclines topoisomerase II inhibitor. Epirubicin is a very effective anticancer drug, but the development of cardiotoxicity and drug resistance limited its use (Hu et al., 2014). The need to resolve the resistance problem as well as decreasing the therapeutic effective dose is necessary to get rid cardiotoxicity associated with epirubicin's treatment (Armenian and Bhatia, 2018).

Many natural products which are extracted from plants are attractive candidates for the development of anticancer agents. These natural products have strong anticancer effect, low toxicity, as well as high availability (Liu et al., 2020). In addition, phytochemicals like resveratrol, curcumin, ginsenoside, genistein, gingerol, and quercetin can decrease the adverse effects related to chemotherapy owing to their antioxidation, antimutagenesis, anti-inflammation, and immunomodulation (Liu et al., 2021).

Flavonoids are classified as polyphenolic compounds that are found in many plants and are used as part of our diet. They attracted the researcher's attention due to their distinct biological applications (Wen et al., 2021). Flavonoids were very effective in preventing as well as treating different types of cancer with less side effects, through their anti-inflammatory, antioxidant, and anti-apoptotic effects as well as their ability to modulate autophagy (Pang et al., 2021; Wang et al., 2022).

Autophagy is an important homeostatic process which is responsible for the degradation of damaged organelles and proteins inside the cell by the lysosome. It is a fundamental survival mechanism that provides energy for the cells (Ashrafizadeh et al., 2019). The autophagy process plays an essential role in the development of cancer and a significant correlation between autophagy and malignancy was established (Turek et al., 2021). This survival process can be either a pro-oncogenic or a tumor suppressor mechanism and a numerous studies have discussed the dual function of autophagy in cancer development and progression by enhancing either the survival of cells or their death (Turek et al., 2021). Consequently, the regulation of autophagy process using natural product or synthetic compounds can be a reliable interventional strategies for treatment of malignant diseases (Liu et al., 2022).

The current study aimed to detect which flavonoid extracted from Physalis pubescens L. leaves has the most cytotoxic effect on the liver cancer cells (Hep-G2) and if it could increase epirubicin efficacy and safety as well as investigate the underlying molecular mechanism.