Genipin Induces Autophagy and Suppresses Cell Growth of Oral Squamous Cell Carcinoma via PI3K/AKT/MTOR Pathway.

Oral squamous cell carcinoma (OSCC) is a common malignant tumor of the head and neck, and it accounts for more than 90% of oral cancer. Due to high mortality, limitations of traditional treatment and many complications, new treatment methods are urgently needed. This study aimed to look into the effect of new potential anti-tumor drug, genipin, on OSCC treatment. In vitro, CCK-8, colony formation, and flow cytometry were used to detect the effect of genipin on SCC-9 and SCC-15 cell lines. Immunofluorescence, real-time PCR, and Western blotting were used to investigate its mechanism. Xenograft tumor model was used to explore the role of genipin in vivo. We found that genipin suppressed cell growth and induced apoptosis in vitro. In addition, the expression of p62 was down-regulated while Beclin1 and LC3II were up-regulated in SCC-25 and SCC-9 cells. 3-methyladenine (3-MA) significantly decreased LC3 (LC3II)+ puncta, but genipin rescuect 3d this reduction. Furthermore, genipin also reduced the expression of p-PI3K, p-AKT, and p-mTOR. In vivo experiment showed that genipin significantly curbed the tumor size and weight. The positive expression of Ki67 protein and number of apoptotic cells were increased. Conclusively, this study implicated that genipin suppresses cell proliferation and stimulated apoptosis, and is the first exploration showing that genipin induces OSCC cell autophagy via PI3K/AKT/mTOR pathway inhibition.

Wei M ，Wu Y ，Liu H ，Xie C ... -  《Drug Design Development and Therapy》

Urolithin A, induces apoptosis and autophagy crosstalk in Oral Squamous Cell Carcinoma via mTOR /AKT/ERK1/2 pathway.

Oral squamous cell carcinoma (OSCC) is the most prevalent malignancy in the world with an alarming rate of mortality. Despite the advancement in treatment strategies and drug developments, the overall survival rate remains poor. Therefore, it is imperative to develop alternative or complimentary anti cancer drugs with minimum off target effects. Urolithin A, a microbial metabolite of ellagic acid and ellagitannins produced endogenously by human gut micro biome is considered to have anti-cancerous activity. However anti tumorigenic effect of urolithin A in OSCC is yet to be elucidated. In this study, we examined whether urolithin A inhibits cell growth and induces both apoptosis and autophagy dependent cell death in OSCC cell lines. The present study aims to evaluate the potential of urolithin A to inhibit OSCC and its regulatory effect on OSCC proliferation and invasion in vitro and in vivo mouse models. We evaluated whether urolithin A could induce cell death in OSCC in vitro and in vivo mouse models. Flow cytometric and immunoblot analysis on Urolithin A treated OSCC cell lines revealed that urolithin A markedly induced cell death of OSCC via the induction of endoplasmic reticulum stress and subsequent inhibition of AKT and mTOR signaling as evidenced by decreased levels of phosphorylated mTOR and 4EBP1. This further revealed a possible cross talk between apoptotic and autophagic signaling pathways. In vivo study demonstrated that urolithin A treatment reduced tumor size and showed a decrease in mTOR, ERK1/2 and Akt levels along with a decrease in proliferation marker, Ki67. Taken together, in vitro as well as our in vivo data indicates that urolithin A is a potential anticancer agent and the inhibition of AKT/mTOR/ERK signalling is crucial in Urolithin A induced growth suppression in oral cancer. Urolithin A exerts its anti tumorigenic activity through the induction of apoptotic and autophagy pathways in OSCC. Our findings suggest that urolithin A markedly induced cell death of oral squamous cell carcinoma via the induction of endoplasmic reticulum stress and subsequent inhibition of AKT and mTOR signaling as evidenced by decreased levels of phosphorylated mTOR and 4EBP1. Urolithin A remarkably suppressed tumor growth in both in vitro and in vivo mouse models signifying its potential as an anticancer agent in the prevention and treatment of OSCC. Henceforth, our findings provide a new insight into the therapeutic potential of urolithin A in the prevention and treatment of OSCC.

Remadevi V ，Jaikumar VS ，Vini R ，Krishnendhu B ，Azeez JM ，Sundaram S ，Sreeja S ... -  《-》

Arglabin is a plant sesquiterpene lactone that exerts potent anticancer effects on human oral squamous cancer cells via mitochondrial apoptosis and downregulation of the mTOR/PI3K/Akt signaling pathway to inhibit tumor growth in vivo.

He W ，Lai R ，Lin Q ，Huang Y ，Wang L ... -  《Journal of BUON》

Tanshinone IIA induces cell death via Beclin-1-dependent autophagy in oral squamous cell carcinoma SCC-9 cell line.

Tanshinone IIA (TAN) is one of the major functional compounds of Salvia miltiorrhiza Bunge and possesses the ability to suppress the growth of multiple cancer cell types via its apoptosis- and autophagy-inducing functions. In this study, the effect of TAN therapy on the survival of oral squamous cell carcinoma (OSCC) was evaluated, and the underlying mechanism involved in the treatment was investigated. Human oral squamous cell carcinoma cell SCC-9 was used for in vitro assays and induction in an OSCC xenograft mouse model. The tumor cells were subjected to TAN administration at different concentrations. Then the apoptosis and autophagy processes in SCC-9 cells were evaluated and the activities of Beclin-1/Atg7/Atg12-Atg5 and PI3K/Akt/mTOR pathways were determined. In addition, by knocking down the expression of Beclin-1 in SCC-9 cells, the study also assessed the role of the indicator in the anti-OSCC effect of TAN. Results of in vitro assays were further validated with an OSCC xenograft mouse model. Administration of TAN-induced cell apoptosis and upregulated the expression of cleaved-caspase-3. Simultaneously, the autophagy process in SCC-9 cells was initiated by TAN, which was signaled by the formation of autophagosomes and increase in the ratio of LC3 II/LC3I. The above processes were associated with the activation of Beclin-1/Atg7/Atg12-Atg5 signaling and inhibition of PI3K/Akt/mTOR signaling. Our results also inferred a partially Beclin-1-dependent mechanism of action of TAN in OSCC cells: knockdown of the Beclin-1 blocked the effect of TAN on SCC-9 cells both in vivo and in vitro. Our study provided a preliminary explanation of the mechanism involved in TAN effect: the agent exerted its autophagy-inducing effect against OSCC in a multipronged manner, by both inducing the Beclin-1/Atg7/Atg12-Atg5 pathway and suppressing the PI3K/Akt/mTOR pathway.

Qiu Y ，Li C ，Wang Q ，Zeng X ，Ji P ... -  《Cancer Medicine》

Overexpression of T-cadherin inhibits the proliferation of oral squamous cell carcinoma through the PI3K/AKT/mTOR intracellular signalling pathway.

Wang Q ，Zhang X ，Song X ，Zhang L ... -  《-》