1.Baicalein induces autophagy in breast cancer cells
Yun LING ; Jue TU ; Zhaowei CAI ; Yueqin CAI ; Yanqing CHU ; Minli CHEN
Chinese Journal of Pathophysiology 2017;33(7):1171-1176
AIM: To investigate the autophagy of breast cancer cells induced by baicalein and to explore its mechanism.METHODS: The effects of baicalein on the viability of MCF-7 cells and 4T1 cells were investigated by MTT assay, and the dosage of the drug was determined.The expression levels of microtubule-associated protein 1 light chain 3-II (LC3-II) and LC3-I in the MCF-7 cells and 4T1 cells treated with baicalein at doses of 25, 50 and 100 μmol/L, or combined with autophagy inhibitor 3-methyladenine (3-MA) were determined by Western blot.In order to confirm the role of baicalein in autophagy, the effect of 3-MA on the apoptosis of both MCF-7 cells and 4T1 cells induced by baicalein was analyzed by flow cytometry.The protein levels of p-mTOR, mTOR, p-AKT and AKT were examined by Western blot and the role of AKT-mTOR pathway in the induction of autophagy in breast cancer induced by baicalein was determined by the combination of activators.RESULTS: Baicalein at 50 μmol/L and above doses significantly inhibited the viability of breast cancer cells in a dose-and time-dependent manner.The expression of LC3-II/LC3-I in both MCF-7 cells and 4T1 cells was significantly enhanced after the action of baicalein, and the ratio of LC3-II/LC3-I was significantly decreased after 3-MA addition.The results of flow cytometry showed that, compared with baicalein group, the combination of baicalein and 3-MA promoted the levels of necrosis and apoptosis.Moreover, the protein levels of p-mTOR and p-AKT were significantly decreased and were rescued by EGF, while their total protein levels were not changed.CONCLUSION: Baicalein induces autophagy through AKT-mTOR pathway both in MCF-7 cells and 4T1 cells.
2.Clinical value of confocal laser endomicroscopy in diagnosis of early esophageal squamous cell carcinoma and precancerous lesions
Lijun GAO ; Tao YU ; Xiaomeng GU ; Xiuli ZUO ; Rui JI ; Changqing LI ; Chuanlian CHU ; Wenbo LI ; Yanqing LI
Chinese Journal of Digestion 2010;30(4):226-229
Objective To assess the value of confocal laser endomieroscopy (CLE) in diagnosis of early esophageal squamous cell carcinoma and precancerous lesions. Methods CLE examination was performed in 41 patients who needed further examination because of lesions in esophagus during July 2008 to April 2009. The diagnosis was made based on the features of esophageal squamous cells which was defined as low grade intraepithelial neoplasia(LGIN), high grade intraepithelial neoplasia (HGIN) and early esophageal squamous cell carcinoma (EC). Biopsy specimens were taken precisely matched to the CLE imaging sites. The result was compared with that of histopathology. Results There were 7281 eonfocal images obtained from 60 target lesions in 41 patients. The sensitivity, specificity and accuracy of CLE were 75.0%, 88.6% and 85.0% in diagnosis of LGIN, respectively, 85.7% ,92.3% and 90.0% in diagnosis of HGIN, respectively,and 88.9% ,96.1% and 95.0%, in diagnosis of EC,respectively. Conclusions It is an effective method for diagnosis of esophageal neoplastic lesions using CLE, which has high accuracy in diagnosis of HGIN and early esophageal cancer.
3.Research advances in persistent hepatitis B virus infection and its mechanism
Huan CHEN ; Yanqing YANG ; Jun CHU
Journal of Clinical Hepatology 2020;36(1):174-177
Hepatitis B virus (HBV) belongs to the Hepadnaviridae family and can cause acute and chronic hepatitis, liver cirrhosis, and even liver cancer in humans. Current antiviral drugs cannot completely eliminate HBV in liver cells and thus it is difficult to achieve a curative effect. In recent years, the mechanism of persistent HBV infection has attracted wide attention, which mainly involves host and virus. This article elaborates on the research advances in persistent HBV infection from the aspect of virus, including covalently closed circular DNA, HBV particles, and HBV components.
4.Mechanism of Pachymic Acid in Inhibiting Invasion and Metastasis of Renal Carcinoma Cells via Regulating MMP/TIMP Balance by Smads
Yuanyuan LUO ; Xinyi FENG ; Zewen CHU ; Hong ZHU ; Yanqing LIU ; Haibo WANG
Chinese Journal of Experimental Traditional Medical Formulae 2023;29(7):76-83
ObjectiveTo investigate the effect and mechanism of pachymic acid (PA) in Poria on the invasion and metastasis of renal carcinoma cells. MethodThe effect of PA (0, 20, 40, 80, 160 μmol·L-1) on cell viability was detected by cell counting kit-8(CCK-8), and the dose of PA was selected for subsequent experiments. The effect of PA (0, 20, 40, 80 μmol·L-1) on cell proliferation was evaluated by colony formation assay. The effect of PA (0, 20, 40, 80 μmol·L-1) on cell adhesion ability was observed by cell adhesion assay. The effect of PA (0, 20, 40, and 80 μmol·L-1) on cell invasion and metastasis was investigated by Wound healing assay and Transwell invasion assay. The inhibitory effect of PA (0, 20, 40, 80 μmol·L-1) on cell motility was further observed and verified by high-content imaging technology. The effects of PA (0, 20, 40, 80 μmol·L-1) on the expression of matrix metalloproteinase (MMP)/tissue inhibitor of metalloproteinasas (TIMP) related to invasion and metastasis and Smads were detected by Western blot. ResultCCK-8 results showed that compared with the blank group, the PA groups showed decreased cell viability(P<0.01), with the half-maximal inhibitory concentration (IC50) of ACHN cells of 70.42 μmol·L-1 at 24 h. Colony formation assay showed that the number of cell clonal groups in the PA groups was reduced compared with that in the blank group(P<0.01). Cell adhesion assay showed that compared with the blank group, the PA groups displayed reduced cell adhesion(P<0.01). Wound healing assay showed that the wound healing rate of cells in the PA groups was lower than that in the blank group (P<0.05,P<0.01). Transwell invasion assay showed that compared with the blank group, the number of transmembrane cells in PA groups was reduced(P<0.01). High-content imaging showed that the cumulative migration distance of cells in the PA groups was shorter than that in the blank group(P<0.01). The results of Western blot showed that the protein expression of MMP-2 and MMP-9 in the PA groups decreased (P<0.01), and TIMP-1 protein expression increased (P<0.01) compared with those in the blank group. In addition, compared with the blank group, the PA groups showed decreased protein expression of Smad2 and Smad3 (P<0.01). ConclusionPA can inhibit the invasion and metastasis of renal carcinoma cells presumably through regulating the homeostasis of MMP/TIMP by Smad2/3.
5.Celastrus orbiculatus Extract Promotes Apoptosis of Gastric Cancer Cells by Destroying Mitochondrial Structure
Haibo WANG ; Yuanyuan LUO ; Xinyi FENG ; Tengyang NI ; Zewen CHU ; Miao ZHU ; Yanqing LIU
Chinese Journal of Experimental Traditional Medical Formulae 2022;28(18):46-53
ObjectiveTo study the inhibitory effect of Celastrus orbiculatus extract (COE) on gastric cancer cells, to clarify the specific mechanism of COE promoting the apoptosis of gastric cancer cells by affecting the mitochondrial structure and function, and to provide an experimental basis for the further development and clinical application of C. orbiculatus. MethodBrdu staining combined with flow cytometry and Annexin V-fluorescein isothiocyanate (AnnexinV-FITC) staining combined with flow cytometry were employed to detect the effects of COE (20, 40, 80 mg·L-1) on the proliferation and apoptosis of gastric cancer cells, respectively. The changes in mitochondrial membrane potential were detected with JC-1 mitochondrial membrane potential assay kit. The expression of apoptosis-associated proteins including B-cell lymphoma-2 (Bcl-2), B-cell lymphoma-xL (Bcl-xL), Bcl-2-associated X (Bax), and cysteine aspartutespecific protease-3 (Caspase-3) in gastric cancer cells was determined by Western blot. Transmission electron microscopy was employed to detect changes in the mitochondrial microstructure of gastric cancer cells exposed to COE. Western blot was employed to measure the expression of mitochondrial marker proteins [superoxide dismutase 1 (SOD1), voltage-dependent anion channel (VDAC), prohibitin 1 (PHB1), and heat shock protein 60 (HSP60)] in gastric cancer cells. ResultCompared with the control group, COE (40, 80 mg·L-1) inhibited the proliferation and promoted the apoptosis of gastric cancer cells (P<0.05). Furthermore, COE reduced the mitochondrial membrane potential of gastric cancer cells. Compared with the control group, COE (20, 40, 80 mg·L-1) up-regulated the expression of Bax and Caspase-3 which promoted apoptosis of gastric cells (P<0.05, P<0.01), and COE at 40 and 80 mg·L-1 down-regulated the expression of Bcl-2 and Bcl-xL which inhibited the apoptosis of gastric cancer cells (P<0.01). The results of transmission electron microscopy showed that COE changed the microstructure of gastric cancer cells, which led to the appearance of vacuoles in the cell membrane and mitochondria and damaged the mitochondrial structure. Compared with the control group, COE (20, 40, 80 mg·L-1) changed the expression of mitochondrial marker proteins. Specifically, it up-regulated the expression of SOD1 involved in stress response (P<0.05, P<0.01) and down-regulated that of VDAC, PHB1, and HSP60 associated with mitochondrial stability and permeability (P<0.01). ConclusionCOE can significantly inhibit the proliferation and promote the apoptosis of gastric cancer cells. It may activate the mitochondrial apoptosis pathway by destroying the mitochondrial structure and function of gastric cancer cells.