Cirsiliol regulates mitophagy in colon cancer cells via STAT3 signaling

Abstract

Background Mitophagy is a type of selective autophagy for dysfunctional mitochondria and plays a key role in tumorigenesis and cancer progression. However, whether mitophagy plays a role in colon cancer remains unclear. Cirsiliol is a natural product and has been found to exert anti-cancer effects in multiple tumors. The effects of cirsiliol in the tumorigenesis and progression of colon cancer remain unknown. Methods CCK8 assay, plate cloning assay, and cell scratch assay were performed to determine cell viability, colony formation, and wound healing abilities of HCT116 and SW480 cells. JC-1 staining, H2DCFDA staining, and Mito-Tracker Red staining were carried out to evaluate mitochondrial membrane potential (Δψm), intracellular reactive oxygen species (ROS) level, and mitochondrial morphology. Molecular docking technology was utilized to predict interaction of cirsiliol and signal transducer and activator of transcription 3 (STAT3). Immunofluorescence staining was used to measure nuclear translocation of STAT3. The protein levels of phosphorylated STAT3 (Y705), total STAT3, and mitophagy proteins were detected by western blot. Results In this study, we first found that cirsiliol inhibited cell viability, colony formation, and wound healing abilities of HCT116 and SW480 colon cancer cells. Moreover, cirsiliol suppressed Δψm, increased ROS production, and disrupted mitochondrial morphology via inhibiting the levels of mitophagy proteins including PINK1, Parkin, BNIP3, and FUNDC1. Application of mitophagy activator improved the levels of mitophagy-related proteins, and ameliorated Δψm and ROS levels. According to the result of molecular docking, we found that cirsiliol potentially bound to the SH2 domain of STAT3, the key domain for the functional activation of STAT3. Moreover, it was found that cirsiliol inhibited constitutive and IL‑6‑induced STAT3 phosphorylation and nuclear translocation by western blot and immunofluorescence analysis. Comparing with cirsiliol group, we found that overexpression of STAT3 restored the expressions of mitophagy proteins. Conclusions Cirsiliol targets STAT3 to inhibit colon cancer cell proliferation by regulating mitophagy.

Cirsiliol induces autophagy and mitochondrial apoptosis through the AKT/FOXO1 axis and influences methotrexate resistance in osteosarcoma

“…Cirsiliol is a flavonoid that has been reported to have therapeutic effects on esophageal squamous cell carcinoma, melanoma, non-small cell lung cancer and breast cancer [ 13 , 15 , 40 , 41 ]. It may affect mitochondrial function and ATP generation or target the appropriate protein to exert its inhibitory effects [ 14 , 42 ]. However, the mechanism of action of cirsiliol in OS is unknown, warranting further investigation, particularly in resistant cell lines.…”

“…It is reported that cirsiliol exerts multiple pharmacological effects, including anti-cancer, anti-inflammatory and anti-oxidative stress [ 10 – 13 ]. Although cirsiliol has been proven to be effective in treating esophageal squamous cell carcinoma and colon cancer [ 14 , 15 ], the effect and underlying molecular mechanisms of cirsiliol in OS remain elusive.…”

“…In addition, the damaged mitochondria are encapsulated by autophagosomes and degraded through the lysosomal pathway [ 18 ]. Several studies have shown that mitochondrial imbalance and altered autophagy levels affect tumor progression [ 14 , 19 , 20 ]. However, the precise underlying mechanisms in OS are yet to be elucidated.…”

Ethnobotanical Uses and Pharmacological Activities of Moroccan Ephedra Species

“…4 a). Cirsiliol is an interesting compound regulator of mitophagy in cancer cells [103], apparently acting as an inhibitor of tyrosine kinase TYK2 (K D = 0.8 µM) in cancer cells and tumors [104]. Its anticancer effects have been well evidenced using different cell lines and tumor models in recent years [105,106].…”

Identification of the mitophagy-related diagnostic biomarkers in hepatocellular carcinoma based on machine learning algorithm and construction of prognostic model

“…In this situation, mitochondria can be cleaned by a process known as mitophagy, a kind of selective autophagy. Mitophagy has been shown to play a function in either promoting or restricting carcinogenesis (9)(10)(11)(12). Furthermore, many studies have revealed that mitophagy is involved in immune function regulation (13).…”