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MAPK kinase 1 (MEK1) is an upstream protein kinase of extracellular signal regulated kinase (ERK), which activates the ERK/MAPK (mitogen activated protein kinase) pathway. Importantly, bioinformatic analysis has shown that there is a target complementary binding site between miR‑101 and MEK1. The present study aimed to ascertain whether or not miR‑101 plays a role in regulating MEK1 expression, ERK/MAPK pathway activity, and the proliferation and apoptosis in a diffuse large B cell lymphoma (DLBCL) cell line. DLBCL tumor samples were collected from patients in our hospital, and lymphatic tissues with reactive lymphoid hyperplasia were selected as controls. The patients were divided into high and low expression groups, and then the survival rate of the two groups was compared using Kaplan‑Meier method, as well the effect of miR‑101 and MEK1 mRNA expression on survival and prognosis was analyzed. The expression of miR‑101, MEK1 and p‑MEK1 between normal lymphoblastic cell lines (HCC1954 BL and NCI‑BL2009) and lymphoma cell lines (SU‑DHL‑4 and Farage) was compared. Lymphoma SU‑DHL‑4 and Farage cells were cultured in vitro, and then divided into the following groups: miR‑NC group; miR‑101 mimic group; siRNA‑NC group; and siRNA‑MEK1 group. The expression of miR‑101, MEK1, p‑MEK1, p‑ERK1/2 and Bcl‑2 was compared. Cell apoptosis was detected by flow cytometry, and cell proliferation was detected by EdU staining. The results showed that targeted regulation existed between miR‑101 and MEK1, and the decreased expression of miR‑101 was related to the pathogenesis and prognosis of DLBCL. Upregulation of miR‑101 inhibited DLBCL cell proliferation and facilitated apoptosis by inhibiting the expression of MEK1.

Objective: To determine effect of G9a inhibitor BIX-01294 on proliferation, apoptosis and histone methylation of acute T lymphoblastic leukemia cells (MOLT-4 and Jurkat) and to explore the underlying mechanism., Methods: Cell proliferation was detected by MTT assay and apoptosis and cell cycle were measured by flow cytometry. Western blot was performed to determine expression of caspase-3, Bcl-2, Bax, P21, P15 and DNMT1 as well as levels of histone H3 acetylation, histone H3K9 mono- di- and tri-methylation., Results: BIX-01294 inhibits expression of Bcl-2, upregulates expression of Bax and caspase-3 and induces cell apoptosis. BIX-01294 upregulates cell cycle inhibitor P21 expression and induces cell cycle arrest in the phase G0/G1. Furthermore, BIX-01294 suppresses expression of DNA demethylase DNMT1 and promotes expression of tumor suppressor protein P15, thereby inhibiting proliferation of MOLT-4 and Jurkat cells. BIX-01294 downregulates histone H3K9 mono- and di-methylation levels and has no effect on H3K9 trimethylation and histone H3 acetylation., Conclusion: Taken together, our results indicate that by regulating H3K9 methylation and cell cycle, BIX-01294 inhibits the proliferation and induces apoptosis of acute T lymphoblastic leukemia cells., (Copyright © 2017. Published by Elsevier Ltd.)

Glioblastoma multiforme is a type of central nervous system tumor with extremely poor prognosis. Previously, hydrogen peroxide (H 2 O 2 ), which promotes the oxidative stress response, has been reported to induce the apoptosis of glioma cells. Recently, secreted frizzled-related protein 1 (SFRP1) has been shown to be associated with various types of malignant tumors and with H 2 O 2 -induced oxidative stress in cardiomyocytes by negatively regulating the Wnt signaling pathway. This study aimed to explore SFRP1 expression and its roles in H 2 O 2 -induced apoptosis in human glioma cells. We found that the SFRP1 level was decreased in several human glioma cell lines, including U87, U251, and SW1783 cells. In U251 cells, SFRP1 could function as a cancer suppressor gene, and the growth of U251 cells could be inhibited not only by H 2 O 2 but also by the overexpression of SFRP1. Furthermore, we demonstrated that H 2 O 2 -induced SFRP1 gene demethylation partially contributed to H 2 O 2 -induced U251 cell apoptosis, which was verified by studies using an SFRP inhibitor (WAY-316606). Our research identified that H 2 O 2 -induced SFRP1 gene demethylation contributes to H 2 O 2 -induced apoptosis in human U251 glioma cells.

G9a is a mammalian histone methyltransferase that contributes to the epigenetic silencing of tumor suppressor genes. Evidence suggests that G9a is required to maintain the malignant phenotype, but little documentation show the role of G9a function in mediating tumor growth. We retrospectively analyzed the protein of G9a and monomethylated histone H3 lysine 9 (H3K9 me1), and dimethylated histone H3 lysine 9 (H3K9 me2) in 175 cases of gastric carcinoma by immunohistochemistry. RNAi-based inhibition of G9a in MGC803 cancer cell line was studied. G9a depletion was done by transient transfection using Lipofectamine 2000. Depletion efficiency of G9a was tested using real-time PCR and western blot analysis. Cell apoptosis and proliferation were detected by TUNEL assay and MTT, respectively. The proteins of H3K9 me1, me2, trimethylation of H3K9 (H3K9 me3), monomethylated histone H3 lysine 27 (H3K27 me1), dimethylated histone H3 lysine 27 (H3K27 me2) and histone acetylated H3, apoptotic proteins were studied by western blot analysis. G9a and H3K9 me2 expression was higher in gastric cancer cells compared to the control (p<0.05). Both G9a and H3K9 me2 were positively correlated with the degree of differentiation, depth of infiltration, lymphatic invasions and tumor-node-metastasis stage in gastric carcinoma, (p<0.05). RNAi-mediated knockdown of G9a induced cell apoptosis and inhibited cell proliferation. Depletion of G9a reduced the levels of H3K9 me1 and me2, H3K27 me1 and me2. Nonetheless, it did not activate acetylation of H3 and H3K9 me3. These data suggest that G9a is required in tumorigenesis, and correlated with prognosis. Furthermore, G9a plays a critical role in regulating epigenetics. Depletion of G9a inhibits cell growth and induces cells apoptosis in gastric cancer. It might be of therapeutic benefit in gastric cancers.

Objective: To investigate the effect of monoamine oxidase inhibitor phenelzine on proliferation, apoptosis and histone modulation in acute lymphoblastic leukemia cell line Molt-4 cells., Methods: The effect of Phenelzine on cell proliferation was detected by MTT. Apoptotic rate was measured by flow cytometry. The variation of apoptosis associated proteins Caspase-3, Bcl-2 and Bax, cyclin-dependent kinase inhibitor p21, tumor suppressor protein p15, and the expression level of histone methylation of H3K4, H3K9 and histone acetylation of H3, DNMT1 were detected by Western Blot., Results: ① Molt-4 cell proliferation rates were (87.68±3.54)%, (67.84±3.24)%, (51.48±3.37)%, (28.72±2.56)% respectively after exposured to phenelzine at 5, 10, 15, 20 μmol/L for 24 h, P<0.05. ② After 10 μmol/L of phenelzine exposure for 24, 48, 72 h, cell proliferation rates were (67.84±3.24)%, (50.24±2.01)%, (40.31±2.25)%, P<0.05. ③ The apoptotic rates were (13.64±2.58)%, (31.24±3.42)%, (56.37±4.26)% after phenelzine treatment at 5, 10, 20 μmol/L for 24 h, which was concentration dependent. ④ Phenelzine could upregulate the expression of Bax, caspase-3, p21, and downregulate Bcl-2 expression. Phenelzine upregulated the methylation level of histone H3K4me1, H3K4me2 and histone acetylated H3, while it didn't change the level of histone H3K4me3, H3K9me1, H3K9me2. ⑤ Phenelzine inhibited DNMT1 expression and promoted p15 expression., Conclusions: Phenelzine increased the methylation of histone H3K4me1, H3K4me2, acetylation of histone H3 and p21, and decreased the expression of DNMT1 and p15, and ultimately inhibited the proliferation and apoptosis of Molt-4 cells.

Background: The canonical Wnt signaling pathway has been considered as a potent oncogenic signaling in the initiation and progression of hematological malignancies. As a key regulator of the Wnt signaling pathway, the role of β-catenin in mantle cell lymphoma (MCL) pathogenesis and progression was investigated in this study., Material and Methods: A total of 30 MCL samples were collected from patients and were examined for the expression of β-catenin and p-GSK3β using immunohistochemical (IHC) staining. Further in vitro studies employed MTT and Western blot assays detecting proliferation and apoptosis-related proteins in MCL cell line Jeko-1, which were transfected with β-catenin shRNA or specific inhibitor XAV939., Results: Expression of β-catenin and phosphorylated glycogen synthase kinase-3 beta (p-GSK3β) in MCL was significantly higher than those in controlled samples. In vitro studies indicated that β-catenin knockdown significantly inhibited cell proliferation and induced apoptosis in Jeko-1 cells. Furthermore, XAV939 induced apoptosis and growth arrest in Jeko-1 cells. Both inhibitory agents increased Bax and caspase 3 proteins, and decreased Bcl-2, c-Myc, and Cyclin D1 proteins., Conclusions: The specific inhibition of β-catenin induces apoptosis and growth arrest, making it a potential therapeutic target against MCL.

Aims: To investigate the involvement of JARID1B histone methyltransferase in the epigenetic change of euchromatic promoter in mantle cell lymphoma (MCL) and acute leukemia., Methods: We retrospectively analyzed the protein of JARID1B and tri-methylated histone H3 lysine 4 (H3K4), histone H3 lysine 9 (H3K9), and cyclin D1 and Ki67 in 30 cases of MCL by immunohistochemistry. JARID1B was depleted by small interfering RNA (siRNA), and cell apoptosis and cell proliferation were detected by flow cytometry and MTT [3-(4,5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide], histone tri-methylated H3K4 and histone acetylated H3, H4, cyclin D1, Bcl-2, procaspase-3, C-myc were studied by Western blot., Results: We demonstrated that JARID1B was upregulated and histone tri-methylated H3K4 was downregulated in MCL compared to proliferative lymphadenitis, P < 0.05. The expression of histone methylated H3K9 was similar in both. Histone methylation of H3K4 was positively correlated with Ki67 in MCL (Kappa = 0.757, P < 0.05). This study showed that depletion of JARID1B cleavage apoptotic proteins of Bcl-2, procaspase-3, C-myc and resulted in loss cell viability and inducing apoptosis in Jeko-1 and HL-60 cell lines. JARID1B siRNA improved tri-methyl H3K4 and histone acetylated H3 and inhibited cyclin D1, but did not affect histone acetylated H4., Conclusions: This study revealed hyper JARID1B expression and hypo histone H3K4 tri-methylation in MCL. We identify depletion JARID1B as a demethylase which is capable of removing three methyl groups from H3K4 and up-regulating histone acetylation of H3 in both cell lines. Interestingly, depletion of JARID1B inhibits Cyclin D1, which is one of the genes contributes to MCL pathogenesis. JARID1B might be one of therapeutic targets in acute leukemia and MCL.

Objective: To investigate the effect of silencing histone deacetylases 1 (HDAC1) gene by RNA interference on the proliferation, apoptosis and histone modulation in gastric cancer MGC-803 cell line., Methods: The optimal segment targeting HDAC1 gene was designed and transfected into MGC-803 cells by Lipofectamine TM2000. HDAC1 mRNA and protein in the transfected cells were detected by RT-PCR and Western blotting, respectively. The growth inhibition of MGC803 cells was evaluated by MTT assay and the cell apoptosis was detected with TUNEL assay. The expression of Bcl-2, procaspase-9, procaspase-3, c-Myc, histone acetylation of H3, H4, and histone methylation of H3K9 was detected by Western blotting., Results: The siRNA targeting HDAC1HDAC1 markedly suppressed mRNA expression, inhibited cell proliferation and induced apoptosis of MGC-803 cells in a concentration manner. Transfection of the cells with HDAC1 siRNA at 0, 30, 60, and 120 nmol/L for 24 h resulted in a cell apoptotic rate of (4.8∓2.7)%, (18.5∓3.5)%, (41.4∓4.3)%, and (59.2∓5.5)%, respectively, and caused down-regulation of the expressions of Bcl-2, proCaspase9, proCaspase3 and c-Myc, upregulation of histone acetylation of H3, H4, and down-regulation of histone methylation of H3K9., Conclusion: Silencing HDAC1 gene expression with HDAC1 siRNA can promote histone H3 and H4 acetylation and inhibit histone methylation of H3K9 to suppress the proliferation and induce apoptosis of gastric cancer MGC-803 cells.

Isothiocyanates are potent chemopreventive agents for carcinogen-induced cancers in rodents. The major mode of action for chemoprevention is cytoprotection i.e. inducing detoxifying enzymes to remove the carcinogens, thus blocking the initiation of carcinogenesis. Analysis has indicated that isothiocyanates also act at the post-initiation levels of carcinogenesis. We have also reported that the phenylhexyl isothiocyanate (PHI) induced growth arrest and apoptosis in human leukemia HL-60 cells in culture. Since then we have investigated the in vivo efficacy of PHI. The effects of PHI were evaluated in immunodeficient mice, with xenografts of human leukemia HL-60 cells. The maximum tolerated dose (MTD) was determined. The experimental mice received 80% of the MTD. Oral feedings of PHI significantly reduced tumor incidence (p<0.05) without overt toxicity. PHI inhibited cell cycle progression through the down-regulation of cyclin expression, Rb phosphorylation and the up-regulation of the cdk-inhibitors. Apoptosis was significantly increased in the treated tumors but not in the normal mouse tissues. In conclusion, PHI induced apoptosis and inhibited the growth of xenografts by targeting the cell cycle regulators. PHI induced selective apoptosis effects in the rapidly growing tumor cells but not in the normal tissues.

The aim of the present study was to investigate the specific effect and possible mechanisms of phenylhexyl isothiocyanate (PHI) on cell proliferation and apoptosis in acute myeloid leukemia M2 cell lines. Cell proliferation in several hematological tumor cells lines following PHI treatment was evaluated in vitro using a Cell Counting Kit-8. The apoptosis and cell cycle of Kasumi-1 and SKNO-1 cells (human M2 cell lines) following exposure to PHI were examined using flow cytometry. A colony-formation assay was used to identify the inhibitory effect of PHI on Kasumi-1 cells in vitro. Furthermore, Kasumi-1 ×enograft tumor models were established. The antitumor effect of PHI was observed in vivo by measuring the size of the resulting xenograft tumors. The apoptosis of the xenograft tumor cells was measured using a TUNEL assay. Finally, protein expression levels were assessed by western blotting. PHI inhibited cell growth in 16 hematological tumor cell lines, with Kasumi-1 and SKNO-1 cells being the most sensitive. In vitro treatment induced apoptosis and inhibited cell cycle arrest at the G0/G1 phase in a dose- and time-dependent manner. PHI also inhibited growth and induced apoptosis in vivo. The compound increased the expression of caspases 3, 9 and 8, Fas and poly (ADP-ribose) polymerase. Furthermore, PHI enhanced the protein expression of p53, Bax and p21 in a dose-dependent manner. In conclusion, PHI had a specific and notable inhibitory effect on Kasumi-1 and SKNO-1 M2 cell lines in vivo and in vitro. Treatment inhibited cell cycle arrest at the G0/G1 phase, and induced apoptosis through the mitochondrial and Fas death receptor pathways. PHI restored the activity of mutated P53 and reactivated the P53 pathway, highlighting it as a potential target drug for mutated P53. [ABSTRACT FROM AUTHOR]

BACKGROUND: MicroRNA-34a (miR-34a), as a tumor-suppressive miRNA, has been found to induce cell apoptosis in acute myeloid leukemia (AML). However, the diagnostic and prognostic significance of miR-34a in AML remains largely unknown. OBJECTIVE: We aimed to explore its associations with clinical characteristics and prognosis of AML patients. METHODS: This study detected serum miR-34a level in 117 diagnosed AML patients and 60 control subjects by using qRT-PCR, and results were compared to clinical features and patient outcome. Since cytogenetically-normal AML (CN-AML) has a good uniformity of cytogenetics and provides a perfect platform for detection of AML biomarkers, we further analyzed miR-34a expression in 56 CN-AML subjects. RESULTS: We found that miR-34a was significantly downregulated in AML and CN-AML patients. MiR-34a underexpression was commonly observed in AML patients with intermediate/poor risk cytogenetic, and M5 subtype. ROC analysis demonstrated that serum miR-34a could well identify AML/CN-AML patients from healthy individuals. More importantly, miR-34a expression was found negatively correlated with aggressive clinical variable, and served as an independent prognostic indicator. In addition, AML/CN-AML patients with low miR-34a expression displayed shorter overall and recurrence free survival. CONCLUSIONS: Altogether, miR-34a might have an application as a diagnostic and prognostic indicator for AML patients. [ABSTRACT FROM AUTHOR]

This study aimed to evaluate the ability of compound 13d to induce autophagy and to promote apoptosis of tumor cells and its interaction mechanism. Using CCK-8 assay, transwell assay, fluorescence resonance energy transfer melting analysis (FRET), transmission electron microscopy, flow cytometry assay, immunofluorescence assay, Western blot analysis, and wound healing assay. The results indicated that compound 13d could induce autophagy and apoptosis of gastric cancer cells. Moreover, the findings of CCK-8 assay, colony formation, migration and invasion assay, and wound healing assay revealed that compound 13d would effectively inhibit cell proliferation, migration, and invasion. Its IC 50 value is about 2.4 μM against gastric cancer cells, which is similar to positive drug‑platinum. 13d specific induction of telomere G-quadruplex formation was proved in extracellular FRET melting assay, and indirectly affected telomerase activity. G-quadruplex formation promoted cell apoptosis and autophagy. Upon incorporating the autophagy inhibitors 3-MA and HCQ, the expression of the autophagy marker protein LC3 was then checked, suggesting that the compound 13d influences the autophagy flux. Furthermore, knocking down the autophagy-related gene Atg5 to reduce the level of autophagy enhances the anti-tumor activity and increases apoptotic cells' proportion. Mechanistic experiments have shown that blocking the Akt/m-TOR signal pathway plays a crucial role in autophagy and G-quadruplex induced telomere dysfunction. DNA damage is the leading cause of autophagy. Compound 13d combined with autophagy inhibitor can inhibit tumor cells more effectively. Our findings demonstrate that compound 13d as a telomeric G-quadruplex ligand induces Telomere dysfunction, DNA damage response, autophagy, and apoptosis in gastric cancer cells by blocking the Akt/m-TOR signaling pathway. [Display omitted] • This study aimed to evaluate the ability of a 1,10-phenanthroline derivative (13d) to kill gastric cells and its interaction mechanism. • The findings revealed that 13d would effectively inhibit cell proliferation, migration, and invasion. • 13d triggers cytoprotective autophagy by blocking the Akt/mTOR signal pathway in autophagy-dependent gastric cancer cells. [ABSTRACT FROM AUTHOR]

Background: miR-100 is reported to be associated with cell proliferation and apoptosis. However, the function of miR-100 in mantle cell lymphoma (MCL) is unknown. The purpose of this study is to analyze the abnormal expression of miR-100 and mTOR in MCL together with their potential biological function and pathogenesis. Method: Eighteen MCL tissue samples and 3 cell lines (Jeko-1, Mino, Granta-519) were investigated in this research study, while eighteen samples of proliferative lymphadenitis from patients and peripheral lymphocyte cells from healthy volunteers served as controls. The expression and alteration of miR-100 and mTOR mRNA were detected by RT-PCR. The expression and alteration of mTOR protein were explored by Western blot. LV-miR-100-up and LV-mTOR-RNAi were constructed and transfected by lentivirus transfection. Cell proliferation, cell apoptosis and the cell cycle were detected using CCK-8 and flow cytometry. Bioinformatics prediction software was used to predict the miR-100 target gene of mTOR. A double luciferase experiment was used to verify miR-100 targeting at the mTOR-3′-UTR. The interaction between miR-100 and mTOR was further studied using recovery experiments. GraphPad Prism 7 software (version 7.2) was used for statistical analysis, and a P value < 0.05 was considered statistically significant. Results: We found that the expression of miR-100 mRNA in MCL tissues and cell lines was lower, while that of the mTOR protein was higher. There was a negative correlation between miR-100 and mTOR in both MCL tissues and cell lines. Promoting miR-100 and inhibiting mTOR could inhibit cell proliferation, induce cell apoptosis and block the cell cycle in the G1 phase. A double luciferase reporter assay showed that mTOR was one of the target genes of miR-100. The recovery experiment demonstrated that PV-mTOR-up partially set off the effect of LV-miR-100-up on decreasing mTOR expression, inhibiting proliferation, inducing apoptosis and blocking the cell cycle in G1 phase in both Jeko-1 and Mino cells. Conclusions: Abnormal expression of miR-100 and mTOR was found in MCL, which included downregulation of miR-100 and upregulation of mTOR. The expression of mTOR is negatively correlated with miR-100. It may play an important role in MCL pathogenesis. miR-100 up-regulation can inhibit cell proliferation, promote cell apoptosis, and inhibit cell cycle in G1 phase by targeting the mTOR gene. miR-100 may potentially be an anti-mantle cell lymphoma gene. [ABSTRACT FROM AUTHOR]