OBJECTIVE: To investigate the effects of asperuloside on cervical cancer based on endoplasmic reticulum (ER) stress and mitochondrial pathway. METHODS: Different doses (12.5-800 µg/mL) of asperuloside were used to treat cervical cancer cell lines Hela and CaSki to calculate the half maximal inhibitory concentration (IC₅₀) of asperuloside. The cell proliferation was analyzed by clone formation assay. Cell apoptosis, intracellular reactive oxygen species (ROS) and mitochondrial membrane potential were determined by flow cytometry. The protein expressions of cleaved-caspase-3, Bcl-2, Bax, Cyt-c, cleaved-caspase-4 and glucose-regulated protein 78 (GRP78) were analyzed by Western blot. And the inhibitor of ER stress, 4-phenyl butyric acid (4-PBA) was used to treat cervical cancer cells to further verify the role of ER stress in the apoptosis of cervical cancer cells induced by asperuloside. RESULTS: Asperuloside of 325, 650, and 1300 µg/mL significantly inhibited the proliferation and promoted apoptosis of Hela and CaSki cells (P<0.01). All doses of asperuloside significantly increased intracellular ROS levels, reduced mitochondrial membrane potential, significantly reduced Bcl-2 protein expression level, and increased Bax, Cyt-c, GRP78 and cleaved-caspase-4 expressions (P<0.01). In addition, 10 mmol/L 4-PBA treatment significantly promoted cell proliferation and reduced apoptosis (P<0.05), and 650 µg/mL asperuloside could reverse 4-PBA-induced increased cell proliferation, decreased apoptosis and cleaved-caspase-3, -4 and GRP78 protein expressions (P<0.05). CONCLUSION Our study revealed the role of asperuloside in cervical cancer, suggesting that asperuloside promotes apoptosis of cervical cancer cells through ER stress-mitochondrial pathway.
Female ; Humans ; Uterine Cervical Neoplasms/metabolism* ; Caspase 3/metabolism* ; bcl-2-Associated X Protein/metabolism* ; Reactive Oxygen Species/metabolism* ; Endoplasmic Reticulum Chaperone BiP ; HeLa Cells ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; Apoptosis ; Endoplasmic Reticulum Stress ; Cell Line, Tumor

OBJECTIVES: Hyperhomocysteinaemia (Hcy) is an independent risk factor for cardiovascular and cerebrovascular diseases. MicroRNA (miR)-18a-5p is closely related to cardiovascular diseases. This study aims to investigate the effects of miR-18a-5p on homocysteine (Hcy)-induced myocardial cells injury. METHODS: H9c2 cells were transfected with miR-18a-5p mimic/miR-18a-5p mimic negative control (NC) or combined with Hcy for intervention, and untreated cells were set as a control group. The transfection efficiency was verified by real-time RT-PCR, and cell counting kit-8 (CCK-8) assay was used to determine cell viability. Flow cytometry was used to detect apoptosis and reactive oxygen species (ROS) levels. Western blotting was performed to measure the protein levels of microtubule-associated protein 1 light chain 3 (LC3)-I, LC3-II, Beclin1, p62, Bax, Bcl-2, and Notch2. Dual luciferase reporter assay was used to detect the interaction of miR-18a-5p with Notch2. RESULTS: Compared with the control, treatment with Hcy or transfection with miR-18a-5p mimic alone, or combined treatment with Hcy and miR-18a-5p mimic/miR-18a-5p mimic NC significantly reduced the H9c2 cell viability, promoted apoptosis and ROS production, up-regulated the expressions of Bax and Beclin, down-regulated the expressions of Bcl-2, p62, and Notch2, and increased the ratio of LC3-II/LC3-I (all P<0.05). Compared with the combined intervention of miR-18a-5p mimic NC and Hcy group, the above indexes were more significantly changed in the combined intervention of miR-18a-5p mimic and Hcy group, and the difference between the 2 groups was statistically significant (all P<0.05). There is a targeted binding between Notch2 and miR-18a-5p. CONCLUSIONS MiR-18a-5p could induce autophagy and apoptosis via increasing ROS production in cardiomyocytes, and aggravate Hcy-induced myocardial injury. Notch2 is a target of miR-18a-5p.
Apoptosis/genetics* ; Autophagy/genetics* ; bcl-2-Associated X Protein ; MicroRNAs/metabolism* ; Proto-Oncogene Proteins c-bcl-2/genetics* ; Reactive Oxygen Species ; Rats ; Animals ; Myocytes, Cardiac/drug effects* ; Homocysteine/adverse effects* ; Hyperhomocysteinemia

Drastic surges in intracellular reactive oxygen species (ROS) induce cell apoptosis, while most chemotherapy drugs lead to the accumulation of ROS. Here, we constructed an organic compound, arsenical N-‍(4-(1,3,2-dithiarsinan-2-yl)phenyl)acrylamide (AAZ2), which could prompt the ROS to trigger mitochondrial-dependent apoptosis in gastric cancer (GC). Mechanistically, by targeting pyruvate dehydrogenase kinase 1 (PDK1), AAZ2 caused metabolism alteration and the imbalance of redox homeostasis, followed by the inhibition of phosphoinositide-3-kinase (PI3K)/protein kinase B (AKT)/mammalian target of rapamycin (mTOR) pathway and leading to the activation of B-cell lymphoma 2 (Bcl2)/Bcl2-associated X (Bax)/caspase-9 (Cas9)/Cas3 cascades. Importantly, our in vivo data demonstrated that AAZ2 could inhibit the growth of GC xenograft. Overall, our data suggested that AAZ2 could contribute to metabolic abnormalities, leading to mitochondrial-dependent apoptosis by targeting PDK1 in GC.
Humans ; Signal Transduction ; Stomach Neoplasms/drug therapy* ; Reactive Oxygen Species/metabolism* ; Proto-Oncogene Proteins c-akt/metabolism* ; Apoptosis ; Proto-Oncogene Proteins c-bcl-2 ; Cell Line, Tumor

OBJECTIVE: To investigate the effects of different manners of heat exposure on thoracic aorta injury in spontaneously hypertensive rats (SHRs) and explore the underlying mechanism. METHODS: Normal 6 to 7-week-old male SHRs were randomized into control group (cage at room temperature), intermittent heat exposure group (SHR-8 group, exposed to 32 ℃ for 8 h daily for 7 days) and SHR-24 group (with continuous exposure to 32 ℃ for 7 days). After the treatments, the pathologies of the thoracic aorta of the rats were observed with HE staining, and the expressions of Beclin1, LC3B and p62 were detected with Western blotting and immunofluorescence assay; TUNEL staining was used to observe cell apoptosis in the thoracic aorta, and the expressions of caspase-3, Bax, and Bcl-2 were detected using Western blotting. The effects of intraperitoneal injections of 3-MA (an autophagy agonist), rapamycin (an autophagy inhibitor) or compound C 30 min before intermittent heat exposure on the expressions of proteins associated with autophagy, apoptosis and the AMPK/mTOR/ULK1 pathway in the aorta were examined with immunohistochemistry. RESULTS: In SHR-8 group, the rats showed incomplete aortic intima with disordered cell distribution and significantly increased expressions of Beclin1, LC3II/LC3I and Bax, lowered expressions of p62 and Bcl-2, and increased apoptotic cells in the thoracic aorta (P < 0.05). Pretreatment with 3-MA obviously inhibited the expressions of autophagy- and apoptosis-related proteins, whereas rapamycin promoted their expressions. Compared with the control group, the rats in SHR-8 group had significantly down-regulated p-mTOR and up-regulated p-AMPK and p-ULK1 expression of in the aorta; Treatment with compound C obviously lowered the expressions of p-AMPK and p-ULK1 and those of LC3B and Beclin1 as well. CONCLUSION In SHRs, intermittent heat exposure causes significant pathologies and promotes autophagy and apoptosis in the thoracic aorta possibly by activating the AMPK/mTOR/ULK1 pathway.
Rats ; Male ; Animals ; Rats, Inbred SHR ; AMP-Activated Protein Kinases/metabolism* ; bcl-2-Associated X Protein/metabolism* ; Aorta, Thoracic ; Beclin-1 ; Hot Temperature ; TOR Serine-Threonine Kinases/metabolism* ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; Apoptosis ; Aortic Diseases ; Autophagy ; Autophagy-Related Protein-1 Homolog/metabolism*

OBJECTIVE: To investigate the effect of baicalin on the growth of extranodal NK/T cell lymphoma (ENKTCL) cells and its related mechanism. METHODS: Normal NK cells and human ENKTCL cells lines SNK-6 and YTS were cultured, then SNK-6 and YTS cells were treated with 5, 10, 20 μmol/L baicalin and set control. Cell proliferation and apoptosis was detected by Edu method and FCM method, respectively, and expressions of BCL-2, Bax, FOXO3 and CCL22 proteins were detected by Western blot. Interference plasmids were designed and synthesized. FOXO3 siRNA interference plasmids and CCL22 pcDNA overexpression plasmids were transfected with PEI transfection reagent. Furthermore, animal models were established for validation. RESULTS: In control group and 5, 10, 20 μmol/L baicalin group, the proliferation rate of SNK-6 cells was (56.17±2.96)%, (51.92±4.63)%, (36.42±1.58)%, and (14.60±2.81)%, respectively, while that of YTS cells was (58.85±2.98)%, (51.38±1.32)%, (34.75±1.09)%, and (15.45±1.10)%, respectively. In control group and 5, 10, 20 μmol/L baicalin group, the apoptosis rate of SNK-6 cells was (5.93±0.74)%, (11.78±0.34)%, (28.46±0.44)%, and (32.40±0.37)%, respectively, while that of YTS cells was (7.93±0.69)%, (16.29±1.35)%, (33.91±1.56)%, and (36.27±1.06)%, respectively. Compared with control group, the expression of BCL-2 protein both in SNK-6 and YTS cells decreased significantly (P<0.001), and the expression of Bax protein increased in SNK-6 cells only when the concentration of baicalin was 20 μmol/L (P<0.001), while that in YTS cells increased in all three concentrations(5, 10, 20 μmol/L) of baicalin (P<0.001). The expression of FOXO3 protein decreased while CCL22 protein increased in ENKTCL cell lines compared with human NK cells (P<0.001), but the expression of FOXO3 protein increased (P<0.01) and CCL22 protein decreased after baicalin treatment (P<0.001). Animal experiments showed that baicalin treatment could inhibit tumor growth. The expression of CCL22 protein in ENKTCL tissue of nude mice treated with baicalin decreased compared with control group (P<0.01), while the FOXO3 protein increased (P<0.05). In addition, FOXO3 silencing resulted in the decrease of FOXO3 protein expression and increase of CCL22 protein expression (P<0.01, P<0.001). CONCLUSION Baicalin can inhibit proliferation and promote apoptosis of ENKTCL cell lines SNK-6 and YTS, up-regulate the expression of Bax protein, down-regulate the expression of BCL-2 protein, and down-regulate the expression of CCL22 protein mediated by FOXO3. Animal experiment shown that the baicalin can inhibit tumor growth. Baicalin can inhibit the growth and induce apoptosis of ENKTCL cells through FOXO3/CCL22 signaling pathway.
Animals ; Mice ; Humans ; Lymphoma, Extranodal NK-T-Cell/pathology* ; Forkhead Box Protein O3/metabolism* ; bcl-2-Associated X Protein/pharmacology* ; Mice, Nude ; Signal Transduction ; Apoptosis ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; Chemokine CCL22/pharmacology*

OBJECTIVE: To investigate the effects of tanshinone IIA on apoptosis and autophagy induced by hypoxia/reoxygenation in H9C2 cardiomyocytes and its mechanism. METHODS: H9C2 cardiomyocytes in logarithmic growth phase were divided into control group, hypoxia/reoxygenation model group and tanshinone IIA low-dose, medium-dose and high-dose groups (50, 100, 200 mg/L tanshinone IIA were treated after hypoxia/reoxygenation respectively). The dose with good therapeutic effect was selected for follow-up study. The cells were divided into control group, hypoxia/reoxygenation model group, tanshinone IIA+pcDNA3.1-NC group and tanshinone IIA+pcDNA3.1-ABCE1 group. The cells were transfected with the overexpressed plasmids pcDNA3.1-ABCE1 and pcDNA3.1-NC and then treated accordingly. Cell counting kit-8 (CCK-8) was used to detect H9C2 cell activity in each group. The apoptosis rate of cardiomyocytes was detected by flow cytometry. The ATP-binding cassette transporter E1 (ABCE1), apoptosis-related proteins Bcl-2 and Bax, caspase-3, autophagy-related proteins Beclin-1, microtubule-associated protein 1 light chain 3 (LC3II/I) and p62 mRNA expression level of H9C2 cells in each group were detected by real-time fluorescence quantitative reverse transcription-polymerase chain reaction (RT-qPCR). The protein expression levels of the above indexes in H9C2 cells were detected by Western blotting. RESULTS: (1) Cell activity and ABCE1 expression: tanshinone IIA inhibited the activity of H9C2 cells induced by hypoxia/reoxygenation, and the effect was significant at medium-dose [(0.95±0.05)% vs. (0.37±0.10)%, P < 0.01], mRNA and protein expression of ABCE1 were significantly reduced [ABCE1 mRNA (2^-ΔΔCt): 2.02±0.13 vs. 3.74±0.17, ABCE1 protein (ABCE1/GAPDH): 0.46±0.04 vs. 0.68±0.07, both P < 0.05]. (2) Expression of apoptosis-related proteins: medium-dose of tanshinone IIA inhibited the apoptosis of H9C2 cells induced by hypoxia/reoxygenation [apoptosis rate: (28.26±2.52)% vs. (45.27±3.07)%, P < 0.05]. Compared with the hypoxia/reoxygenation model group, medium-dose of tanshinone IIA significantly down-regulated the protein expression of Bax and caspase-3 in H9C2 cells induced by hypoxia/reoxygenation, and significantly up-regulated the protein expression of Bcl-2 [Bax (Bax/GAPDH): 0.28±0.03 vs. 0.47±0.03, caspase-3 (caspase-3/GAPDH): 0.31±0.02 vs. 0.44±0.03, Bcl-2 (Bcl-2/GAPDH): 0.53±0.02 vs. 0.37±0.05, all P < 0.05]. (3) Expression of autophagy-related proteins: compared with the control group, the positive rate of LC3 in the hypoxia/reoxygenation model group was significantly increased, while the positive rate of LC3 in the medium-dose of tanshinone IIA group was significantly decreased [(20.67±3.09)% vs. (42.67±3.86)%, P < 0.01]. Compared with hypoxia/reoxygenation model group, medium-dose of tanshinone IIA significantly down-regulated Beclin-1, LC3II/I and p62 protein expressions [Beclin-1 (Beclin-1/GAPDH): 0.27±0.05 vs. 0.47±0.03, LC3II/I ratio: 0.24±0.05 vs. 0.47±0.04, p62 (p62/GAPDH): 0.21±0.03 vs. 0.48±0.02, all P < 0.05]. (4) Expression of apoptosis and autophagy related proteins after transfection with overexpressed ABCE1 plasmid: compared with tanshinone IIA+pcDNA3.1-NC group, the protein expression levels of Bax, caspase-3, Beclin-1, LC3II/I and p62 in tanshinone IIA+pcDNA3.1-ABCE1 group were significantly up-regulated, while the protein expression level of Bcl-2 was significantly down-regulated. CONCLUSIONS 100 mg/L tanshinone IIA could inhibit autophagy and apoptosis of cardiomyocytes by regulating the expression level of ABCE1. So, it protects H9C2 cardiomyocytes injury induced by hypoxia/reoxygenation.
Humans ; Apoptosis ; ATP-Binding Cassette Transporters/metabolism* ; Autophagy ; bcl-2-Associated X Protein/metabolism* ; Beclin-1/metabolism* ; Caspase 3/metabolism* ; Follow-Up Studies ; Myocytes, Cardiac ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; RNA, Messenger/metabolism* ; Cell Hypoxia

Objective: To investigate the effects of lncRNA DRAIC on proliferation, apoptosis, migration and invasion of lung adenocarcinoma cells and its mechanism. Methods: Reverse transcription-quantitative real-time polymerase chain reaction (RT-qPCR) was used to detect the expression of DRAIC in lung cancer tissues and corresponding adjacent normal tissues of 40 patients with lung adenocarcinoma who underwent surgery in Tangshan People's Hospital from 2019 to 2020. Lung adenocarcinoma cells A549 and H1299 were cultured in vitro and divided into si-NC group, si-DRAIC group, miR-NC group, let-7i-5p mimics group, si-DRAIC+ inhibitor-NC group, and si-DRAIC+ let-7i-5p inhibitor group. CCK-8 method and clone formation experiment were used to detect cell proliferation. Flow cytometry was used to detect cell apoptosis. Transwell array was used to detect the cell migration and invasion. Western blot was used to detect the protein expressions of Caspase-3, Caspase-9, Bcl-2 and Bax. The double luciferase reporter gene experiment was used to verify the regulatory relationship between DRAIC and let-7i-5p. Independent sample t test was used for comparison between two groups, one-way ANOVA was used for comparison between multiple groups, and Pearson correlation analysis was used for correlation analysis. Results: Compared with adjacent tissues, the expression level of DRAIC in lung adenocarcinoma tissues increased (P<0.05), but the expression level of let-7i-5p decreased (P<0.05). The expression levels of DRAIC and let-7i-5p in lung adenocarcinoma tissues were negatively correlated (r=-0.737, P<0.05). The absorbance value of A549 and H1299 cells in the si-DRAIC group at 48, 72 and 96 hours were lower than those in the si-NC group (P<0.05), the number of clones formed [(91.00±6.08 vs. 136.67±6.51); (50.67±1.53 vs. 76.67±4.51)], the number of migration [(606.67±31.34 vs. 960.00±33.06); (483.33±45.96 vs. 741.67±29.67)], the number of invasion [(185.00±8.19 vs. 447.33±22.05); (365.00±33.87 vs. 688.00±32.97)] were lower than those in the si-NC group (P<0.05). However, the apoptosis rates of cells [(13.43±2.79)% vs. (4.53±0.42)%; (23.77±1.04)% vs. (6.60±1.42)%] were higher than those in the si-NC group (P<0.05). The protein expressions of Caspase-3, Caspase-9 and Bax in si-DRAIC group were higher than those in si-NC group, and the protein expression of Bcl-2 was lower than that in si-NC group (P<0.05). DRAIC is located in the cytoplasm. DRAIC targeted and negatively regulated the expression of let-7i-5p. The absorbance values of A549 and H1299 cells in the let-7i-5p mimics group at 48, 72 and 96 hours were lower than those in the miR-NC group (P<0.05), the number of clones formed [(131.33±14.47 vs. 171.33±6.11); (59.33±4.93 vs. 80.33±7.09)], the number of migration [(137.67±3.06 vs. 579.33±82.03); (425.00±11.14 vs. 669.33±21.13)], the number of invasion [(54.00±4.36 vs. 112.67±11.59); (80.00±4.58 vs. 333.33±16.80)] were lower than those in the miR-NC group (P<0.05). However, the apoptosis rates of cells [(14.57±1.10)% vs. (6.97±1.11)%; (23.97±0.42)% vs. (7.07±1.21)%] were higher than those in the miR-NC group (P<0.05). The protein expressions of Caspase-3, Caspase-9 and Bax in let-7i-5p mimics group were higher than those in miR-NC group, and the protein expression of Bcl-2 was lower than that in miR-NC group (P<0.05). The absorbance values of A549 and H1299 cells in the si-DRAIC+ let-7i-5p inhibitor group at 48, 72 and 96 hours were higher than those in the si-DRAIC+ inhibitor-NC group (P<0.05), the number of clones formed [(82.00±5.29 vs. 59.00±5.57); (77.67±4.93 vs. 41.33±7.57)], the number of migration [(774.33±35.81 vs. 455.67±19.04); (569.67±18.72 vs. 433.67±16.77)], the number of invasion [(670.33±17.21 vs. 451.00±17.52); (263.67±3.06 vs. 182.33±11.93)] were higher than those in the si-DRAIC+ inhibitor-NC group (P<0.05). However, the apoptosis rates of cells [(7.73±0.45)% vs. (19.13±1.50)%; (8.00±0.53)% vs. (28.40±0.53)%] were lower than those in the si-NC group (P<0.05). The protein expressions of Caspase-3, Caspase-9 and Bax in si-DRAIC+ let-7i-5p inhibitor group were higher than those in si-DRAIC+ inhibitor-NC group, and the protein expression of Bcl-2 was lower than that in si-DRAIC+ inhibitor-NC group (P<0.05). Conclusion: DRAIC is highly expressed in lung adenocarcinoma, and DRAIC promotes the proliferation, migration and invasion of lung adenocarcinoma cells and inhibits apoptosis by targeting let-7i-5p.
Humans ; Adenocarcinoma/genetics* ; Apoptosis/genetics* ; bcl-2-Associated X Protein/metabolism* ; Caspase 3/metabolism* ; Caspase 9/metabolism* ; Cell Line, Tumor ; Cell Proliferation/genetics* ; Lung/metabolism* ; MicroRNAs/metabolism* ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; RNA, Long Noncoding/genetics*

Objective: To investigate whether tanshinone ⅡA can protect the apoptosis of mice cochlear pericytes induced by high glucose and its specific protective mechanism, so as to provide experimental evidence for the prevention and treatment of diabetic hearing loss. Methods: C57BL/6J male mice were used to prepare type 2 diabetes model, which were divided into normal (NG) group, diabetic (DM) group, diabetic+tanshinone ⅡA (HG+tanshinone ⅡA) group and tanshinone ⅡA group. Each group had 10 animals. Primary cochlear pericytes were divided into NG group, HG group (high glucose 35 mmol/L), HG+tanshinone ⅡA (1, 3, 5 μmol/L) group, HG+Tanshinone ⅡA+LY294002 (PI3K/AKT pathway inhibitor) group, LY294002 group, tanshinone ⅡA group and DMSO group. Auditory brainstem response (ABR) was used to measure hearing threshold. Evans blue was used to detect the permeability of blood labyrinth barrier in each group. TBA methods were used to detect oxidative stress levels in various organs of mice. Morphological changes of stria vascularis were observed by hematoxylin-eosin staining (HE). Evans blue was used to detect the vascular labyrinth barrier permeability in cochlea. The expression of apoptosis protein in stria vascularis pericytes was observed by immunofluorescence. Pericytes apoptosis rate was observed by flow cytometry. DCFH-DA was combined with flow cytometry to detect intracellular ROS content, and Western blot was used to detect the expression of apoptotic proteins (Cleaved-caspase3, Bax), anti-apoptotic proteins (BCL-2) and pathway proteins (PI3K, p-PI3K, AKT, p-AKT). SPSS software was used for statistical analysis. Independent sample t test was performed, and P<0.05 was considered statistically significant. Results: Animal experiments: Tanshinone ⅡA decreased the hearing threshold of DM group [(35.0±3.5) dB SPL vs. (55.3±8.1) dB SPL] (t=4.899, P<0.01), decreased the oxidative stress level in cochlea (t=4.384, P<0.05), improved the structure disorder, atrophy of cochlea vascular lines, vacuole increased phenomenon. Tanshinone ⅡA alleviated the increased permeability of the blood labyrinth barrier [Evans blue leakage (6.84±0.27) AU vs. (8.59±0.85) AU] in the cochlea of DM mice (t=2.770, P<0.05), reversed the apoptotic protein: Caspase3 (t=4.956, P<0.01) and Bax (t=4.388, P<0.05) in cochlear vascularis. Cell experiments: Tanshinone ⅡA decreased intracellular ROS content in a concentration-dependent way (t=3.569, P<0.05; t=4.772, P<0.01; t=7.494, P<0.01); Tanshinone ⅡA decreased apoptosis rate and apoptotic protein, and increased the expression of anti-apoptotic protein, p-PI3K/PI3K and p-AKT/AKT in concentration-dependent manner (all P values<0.05); LY294002 reversed the protective effect of tanshinone ⅡA on pericytes apoptosis (all P values<0.05). Conclusion: Tanshinone ⅡA can inhibit the apoptosis of cochlear pericytes induced by high glucose by reducing oxidative stress level and activating PI3K/AKT signaling pathway under high glucose environment, thus playing a protective role in diabetic hearing loss.
Animals ; Male ; Mice ; Apoptosis ; bcl-2-Associated X Protein ; Diabetes Mellitus, Type 2 ; Evans Blue ; Glucose ; Hearing Loss ; Mice, Inbred C57BL ; Pericytes/metabolism* ; Phosphatidylinositol 3-Kinases/metabolism* ; Proto-Oncogene Proteins c-akt/metabolism* ; Reactive Oxygen Species/metabolism* ; Signal Transduction

OBJECTIVE: To investigate the effect of lactic acid-induced upregulation of PLEKHA4 expression on biological behaviors of glioma cells and the possible molecular mechanism. METHODS: GEO database and GEPIA2 website were used to analyze the relationship between PLEKHA4 expression level and the pathological grade of glioma. A specific PLEKHA4 siRNA was transfected in glioma U251 and T98G cells, and the changes in cell proliferation ability were assessed by real-time cell analysis technology and Edu experiment. The colony-forming ability of the cells was evaluated using plate cloning assay, and cell cycle changes and cell apoptosis were analyzed with flow cytometry. The mRNA expression of PLEKHA4 was detected by PCR in glioma samples and controls and in glioma cells treated with lactic acid and glucose. Xenograft mice in vivo was used to detect tumor formation in nude mice; Western blotting was used to detect the expressions of cyclinD1, CDK2, Bcl2, β-catenin and phosphorylation of the key proteins in the MAPK signaling pathway. RESULTS: The results of GEO database and online website analysis showed that PLEKHA4 was highly expressed in glioma tissues and was associated with poor prognosis; PLEKHA4 knockdown obviously inhibited the proliferation and attenuated the clone-forming ability of the glioma cells (P < 0.05). Flow cytometry showed that PLEKHA4 knockdown caused cell cycle arrest in G1 phase and promoted apoptosis of the cells (P < 0.01). PLEKHA4 gene mRNA expression was increased in glioma samples and glioma cells after lactate and glucose treatment (P < 0.01). PLEKHA4 knockdown, tumor formation ability of nude mice decreased; PLEKHA4 knockdown obviously lowered the expression of cyclinD1, CDK2, Bcl2 and other functional proteins, inhibited the phosphorylation of ERK and p38 and reduced the expression of β-catenin protein (P < 0.01). CONCLUSION PLEKHA4 knockdown inhibited the proliferation of glioma cells and promoted apoptosis by inhibiting the activation of the MAPK signaling pathway and expression of β-catenin. Lactic acid produced by glycolysis upregulates the expression of PLEKHA4 in glioma cells.
Humans ; Animals ; Mice ; Up-Regulation ; beta Catenin/metabolism* ; Mice, Nude ; Brain Neoplasms/pathology* ; Lactic Acid ; Cell Line, Tumor ; Glioma/pathology* ; Cell Proliferation ; Apoptosis ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; RNA, Messenger/genetics* ; Gene Expression Regulation, Neoplastic

OBJECTIVE: To investigate the effects of methionine restriction on proliferation, cell cycle and apoptosis of human acute leukemia cells. METHODS: Cell Counting Kit-8 (CCK-8) assay was used to detect the effect of methionine restriction on HL-60 and Jurkat cells proliferation. The effect of methionine restriction on cell cycle of HL-60 and Jurkat cells was examined by PI staining. Annexin V-FITC / PI double staining was applied to detect apoptosis of HL-60 and Jurkat cells following methionine restriction. The expression of cell cycle-related proteins cyclin B1, CDC2 and apoptosis-related protein Bcl-2 was evaluated by Western blot assay. RESULTS: Methionine restriction significantly inhibited the proliferation of HL-60 and Jurkat cells in a time-dependent manner (HL-60: r =0.7773, Jurkat: r =0.8725), arrested the cells at G2/M phase (P < 0.001), and significantly induced apoptosis of HL-60 and Jurkat cells (HL-60: P < 0.001; Jurkat: P < 0.05). Furthermore, Western blot analysis demonstrated that methionine restriction significantly reduced the proteins expression of Cyclin B1 (P < 0.05), CDC2 (P < 0.01) and Bcl-2 (P < 0.001) in HL-60 and Jurkat cells. CONCLUSION Acute leukemia cells HL-60 and Jurkat exhibit methionine dependence. Methionine restriction can significantly inhibit the proliferation, promote cell cycle arrest and induce apoptosis of HL-60 and Jurkat cells, which suggests that methionine restriction may be a potential therapeutic strategy for acute leukemia.
Humans ; Cyclin B1/pharmacology* ; Cell Proliferation ; Methionine/pharmacology* ; Cell Cycle ; Apoptosis ; Leukemia, Myeloid, Acute ; Cell Division ; Cell Cycle Proteins ; Jurkat Cells ; Proto-Oncogene Proteins c-bcl-2/metabolism* ; HL-60 Cells