Study On The Anti-oral Squamous Cell Carcinoma Activity Of Carnosic Acid Based On Mitochondrial Regulation

Oral squamous cell carcinoma（OSCC）is a type of malignant tumor that occurs in the oral and maxillofacial region.The development of OSCC is promoted by many important risk factors,including betel nut chewing,smoking,alcohol abuse,and human papilloma virus（HPV）.Treatment for OSCC is currently based on surgery,radiation therapy and chemotherapy.Due to the anatomical location of the oral and maxillofacial region,which is of great importance in terms of aesthetics and function,combined with the fact that OSCC is more prone to cervical lymph node metastasis and tumor recurrence rate,most patients’quality of life is often affected after treatment,and the prognosis is not very satisfactory.According to the etiology,pathological manifestations and clinical manifestations of OSCC,analyzing the possible risk factors of the disease and searching for novel drugs with high efficiency and low toxicity and better treatment options are essential for the prevention,treatment and improvement of patient prognosis of the disease.Carnosic acid（CA）is a diterpenoid phenolic compound with multiple biological activities extracted from Rosmarinus officinalis L and Salvia divinorum.In recent years,it has received a lot of attention from scholars at home and abroad due to its advantages of safety and low toxicity and structural stability.It has been confirmed that syringic acid has various pharmacological effects such as anti-inflammatory,oxidative stress,neuroprotective,anti-obesity and anti-tumor.The aim of this study is to investigate the effect of syringic acid on the occurrence and development of OSCC and to explore the possible mechanism of its anti oral squamous carcinoma activity.Translated with cell model of OSCC was established,and the various in vitro cellular phenotypes of syringic acid were verified and inferred by MTT assay,migration assay,apoptosis assay,relevant kit assay,transmission electron microscopy（TEM）assay and western blot analysis.Then combined with the protein level assay,the possible mechanism of its exerting in vitro anti-tumor effects was explored.CA could cause a dose-dependent decrease in cell viability of OSCC,increase the apoptosis rate of tumor cells and inhibit cell migration.It also reduces the membrane potential of mitochondria and increases intracellular levels of reactive oxygen species（ROS）and Ca²⁺.At the protein level,it was found to alter the expression of apoptosis-related proteins.2.The CAL27-and SCC9-xenograft models was constructed,and after the ectopic tumor was formed,the treatment with CA injection was performed on alternate days.After the treatment,tumor tissues,organ tissues and peripheral blood of BALB/c nude mice were taken for further testing to evaluate the in vivo anti-tumor effect of CA,and then combined with western blot analysis to explore the possible mechanism of its in vivo antit-umor effect.The growth of OSCC ectopic tumors was inhibited after treatment with CA.Histopathological examination of the organs did not reveal inflammatory cell infiltration or structural alterations.The expression of apoptosis-related proteins was found to be similarly altered in vivo at the protein level.CA can induce apoptosis in OSCC in vivo and in vitro by a specific mechanism that may be apoptosis mediated by mitochondria.