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As a top leading cause of cancer death in many countries, colorectal cancer (CRC) has drawn increasing attention to the study of the pathological mechanism. According to the "cancer stem cell hypothesis", malignancies originate from a small fraction of cancer cells that show self-renewal properties to initiate and sustain tumor growth and tumor metastasis. Therefore, these cancer stem cells (CSC) probably play important roles in tumor recurrence, metastasis, and drug resistance. Previous research reported that lysine-specific histone demethylase 1 (LSD1) maintains cancer stemness through up-regulating stemness markers SOX2 and OCT4. CD133 is believed to be the most robust surface marker for CRC stem cells, however the regulatory effect of LSD1 on stemness of CD133+ CRC has never been reported. In this study, our objectives included: 1) to isolate pure CD133+ and CD133- cells from SW620 cell line; 2) to investigate the effect of LSD1 on the characteristics of CD133+ stem cancer cells by knocking down the target gene. Results suggested that the SW620 cell line had both CD133+ and CD133- subsets. The CD133+ subset exhibited more CSC-like characteristics compared with the CD133- subset with higher viability, colony formation rate, migration and invasion rate, resistance to anti-cancer drugs, and apoptosis in vitro. The CD133+ also induced faster tumor formation and larger tumors in vivo. In the LSD1-knockdown CD133+ cells, the CSC-like characteristics had been all weakened. We conclude that LSD1 was important for CSCs to maintain their "stemness" features, which could be a potential therapeutic target of CRC.

Objective: To explore whether Mitofusin 2 (Mfn2) is implicated in the pathogenesis of intervertebral disc degeneration (IVDD)., Methods: We detected the protein content of Mfn2 in degenerated human nucleus pulposus (NP) tissues and investigated the effects of Mfn2 knockdown and Mfn2 overexpression on rat nucleus pulposus cells (NPCs) under oxidative stress by using a range of biological techniques. Afterwards, we confirmed the effects of Mfn2 overexpression on NPCs in vivo and further evaluated the therapeutic action of adenovirus (AV)-Mfn2 injection in a rodent IVDD model., Results: Mfn2 expression was decreased in human NP tissues during IVDD. Mfn2 knockdown aggravated the impairment of autophagic flux, mitochondrial dysfunction and cellular apoptosis in rat NPCs after Tert-Butyl hydroperoxide (TBHP) treatment, while Mfn2 overexpression significantly reversed these alterations. Besides, Mfn2 overexpression promoted an ROS (reactive oxygen species)-dependent mitophagy via PINK1 (PTEN-induced putative kinase 1)/Parkin pathway in TBHP-treated NPCs. Inhibition of autophagy with chloroquine (CQ) disordered the protective effects of Mfn2 overexpression on NPCs. Furthermore, Mfn2 overexpression in discs by AV-Mfn2 injection ameliorated the development of IVDD in rats., Conclusion: Mfn2 repression is deeply involved in the pathogenesis of IVDD with its impairment on autophagy, leading to the aggravation of mitochondrial dysfunction and apoptotic cell death, which ought to be a promising therapeutic target for IVDD., (Copyright © 2020 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.)

Objective: To detect the relative expression of long intergenic non-protein coding ribonucleic acid (LINC) 01116 in gastric cancer (GC) tissues and cells and analyze the correlations of LINC01116 expression with the clinicopathologic characteristics of patients and investigate the biological functions of LINC01116 via in vitro experiments., Patients and Methods: The quantitative Real Time Fluorescence-Polymerase Chain Reaction (qRT-PCR) was applied to detect the relative expression level of LINC01116 in 73 cases of tissues and cells in GC patients. The patients were divided into LINC01116 high expression group and LINC01116 low expression group, and the correlations of LINC01116 with patient's pathological characteristics were statistically analyzed. In vitro experiments [cell counting kit-8 (CCK-8) assay, colony formation assay, and flow cytometry] were adopted to investigate the influences of LINC01116 on the biological functions of GC cells., Results: According to the results of qRT-PCR, the expression of LINC01116 was upregulated in 54 out of 73 cases of tissues (fold change >1), and it was upregulated in GC cells compared with that in the normal gastric mucosal epithelial cells (GES-1). The statistical analysis manifested that the highly expressed LINC01116 was positively correlated with the tumor-node-metastasis (TNM) stage (p=0.008), lymph node metastasis (p=0.005), and depth of invasion (p=0.007) of the GC patients. The patients with high expression of LINC01116 in the GC tissues had a shorter survival time than those with low expression (p=0.017). After interference in the expression of LINC01116, it was shown in CCK-8 assay and colony formation assay that the proliferative capacity of the cells was decreased. The results of flow cytometry indicated that the cell cycle was arrested at the G1/G0 phase, and the apoptosis rate was increased., Conclusions: LINC01116 is highly expressed in GC tissues and cells, and highly expressed LINC01116 indicates poor prognosis of the patients, promotes the proliferation, and inhibits the apoptosis of GC cells.

Objective: This study aimed to research the effect of miR-202-5p-mediated ATG7 on autophagy and apoptosis of degenerative nucleus pulposus cells., Patients and Methods: The intervertebral disc nucleus pulposus (NP) tissue of patients with intervertebral disc degenerative disease and normal intervertebral disc nucleus pulposus (NP) tissue of patients with spinal fractures was collected as the research object. Normal NP cells and degenerative NP cells were isolated. Low expression of miR-202-5p and overexpression of ATG7 were carried out in degenerative NP cells. The expression of miR-202-5p and ATG7 mRNA was detected by RT-PCR. The expression of ATG7, LC3-II, Bax, and Bcl-2 proteins was detected by Western blot. The autophagy of cells was detected by MDC staining. The apoptosis of NP cells was detected by flow cytometry. The targeting relationship between miR-202-5p and ATG7 was detected by Dual-Luciferase reporter., Results: In the degenerative NP tissues, miR-202-5p was highly expressed and ATG7 was low expressed. The inhibition of miR-202-5p expression can effectively promote autophagy of NP cells, increase the expression of ATG7 and LC3-II, inhibit the apoptosis of NP cells, inhibit the expression of pro-apoptotic proteins Bax, and promote the expression of pro-apoptotic proteins Bcl-2 proteins. The upregulation of ATG7 expression in degenerative NP cells alone had the same effect as the downregulation of miR-202-5p. The assay of the Dual-Luciferase reporter confirmed the targeting relationship between miR-202-5p and ATG7., Conclusions: MiR-202-5p can affect the autophagy and apoptosis of degenerative nucleus pulposus cells through targeted adjustment of ATG7, which may be a new therapeutic target for intervertebral disc degenerative diseases.

Objective: To investigate the effects of long non-coding ribonucleic acid (lncRNA) small nucleolar RNA host gene 1 (SNHG1) on the neuronal apoptosis in rats with cerebral infarction through the phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) signaling pathway., Materials and Methods: Male Sprague Dawley (SD) rats were divided into M group (model control group), N group (rat model of cerebral infarction) and R group (rat model of cerebral infarction plus lncRNA SNHG1) and then treated accordingly. 2,3,5-triphenyl tetrazolium chloride (TTC) staining was applied to detect the percentage of cerebral infarct volume and apoptosis of brain cells in the three groups of rats; hematoxylin and eosin (HE) staining was utilized to observe the pathological morphology of brain tissues, and Western blotting was performed to measure the protein levels of phosphorylated PI3K (p-PI3K) and p-Akt in the brain tissues., Results: The degree of neurological deficit in the N group was much higher than that in the M group (p<0.05), and it was decreased markedly in the R group compared with that in the N group, with statistically significant differences (p<0.05). In comparison with that in the M group, the cell apoptosis was aggravated notably in the N group and alleviated remarkably in the R group, and the differences were statistically significant (p<0.05). In the N group, the cerebral infarct volume accounted for 33.67% of the whole brain volume, and mild cerebral infarction was detected in the R group, with a percentage of cerebral infarct volume of 20.15%. N group had a more prominent increase in the cerebral infarct volume than the R group (p<0.05). Compared with those in the M group, the pyknotic nuclei and neuron staining of brain tissues were increased significantly, and the neuronal cell injury was aggravated in the N group, while markedly reduced pyknotic nuclei and neuron staining (p<0.05), as well as mild neuronal cell injury (p<0.05), were detected in the R group. The levels of p-PI3K and p-Akt proteins in the brain tissues declined remarkably in the N group compared with those in the R group (p<0.05)., Conclusions: The protective effect of lncRNA SNHG1 on the rats with cerebral infarction is correlated with the activation of the PI3K/Akt signaling pathway.

Objective: Long non-coding RNA DUXAP10 plays a significant role in the tumorigenesis and development of human cancer. The present study was performed to investigate the role of DUXAP10 in biological functions and underlying molecular mechanisms of prostate cancer cells., Materials and Methods: First, the quantitative reverse transcription-polymerase chain reaction (qRT-PCR) was used to detect the expression of DUXAP10 in human prostate cancer cell lines 22RV1, PC3, and DU145. Subsequently, small interfering RNAs (siRNAs) targeting at DUXAP10 mRNA were used to downregulate DUXAP10 expression. Then, the biological functions of DUXAP10 in prostate cancer cells, proliferation, migration, and apoptosis were studied by the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, colony-formation assay, cell cycle analysis, transwell migration assay, wound healing assay, and cell apoptosis assay, respectively. Finally, qRT-PCR analysis and Western blot assay were used to investigate the molecular mechanisms of DUXAP10 underlying the progression of prostate cancer., Results: Results showed that the expression of DUXAP10 was higher in PC3 and DU145 cell lines than that in the 22RV1 cell line. Additionally, the knockdown of DUXAP10 could remarkably inhibit the proliferation, migration, and induce apoptosis of prostate cancer cells, and significantly increase the number of G0/G1 cells in PC3 and DU145 cell lines. Moreover, DUXAP10 could promote the development of prostate cancer by regulating the process of epithelial-mesenchymal transition (EMT)., Conclusions: The findings of this study suggested that the down-regulation of DUXAP10 expression suppressed the progression of prostate cancer by inhibiting cell proliferation, migration and promote cell apoptosis.

Philadelphia chromosome positive (Ph+) acute lymphoblastic leukemia (ALL) is the most fatal leukemia due to the BCR/ABL fusion protein. This fusion protein can induce interleukin 6 (IL-6) expression in leukemia stem cells (LSCs) which sustain stemness by binding IL-6R and activating the Janus kinase (JAK)/signal transducer and activator of the transcription (STAT) pathway. IL-6R was one of the targets of miR-451a down-regulated in LSCs by BCR/ABL. We investigated the relationship between miR-451a, IL-6R, and BCR/ABL in Ph+ ALL and created a strategy to treat this disease. The expression levels of miR-451a and BCR/ABL of Ph+ ALL patients were examined by real-time quantitative polymerase chain reaction (RT-qPCR) and serum IL-6 was tested by enzyme-linked immunosorbent assay. Ph+ ALL cell line SUP-B15 and Ph- ALL cell line Nalm-6 were treated with miR-451a mimic and inhibitor, respectively; proliferation rate was assessed by CCK-8, apoptosis rate was tested by Annexin/PI and the expression levels of Bcl-XL, Bax, cyclin D2 and c-myc were examined by qPCR and western blot (WB). The levels of STAT3, p-STAT3, JAK2, and p-JAK2 were tested by WB. We found that BCR/ABL was inversely related to miR-451a and positively related to IL-6 in Ph+ ALL. MiR-451a inhibited the proliferation of SUP-B15 through the apoptosis pathway. The oncogene c-myc was down-regulated by miR-451a. We confirmed that miR-451a could target IL-6R and inhibit activation of JAK and STAT3. In conclusion, miR-451a is down regulated in Ph+ ALL and increasing the expression levels of miR-451a in leukemia cells can increase the potential of curing this disease.

Background: Previously, we showed that the Zinc finger-containing transcription factor ZNF424 inhibits p21 transcription, which has been widely associated with various cancers. However, because the roles of ZNF424 in tumorigenesis have not been characterized, we correlated ZNF424 expression with tumorigenesis in lung cancer., Results: The present immunohistochemical analyses show significantly lower ZNF424 expression levels in 43 of 60 lung cancer tissues compared with adjacent tissues. Moreover, flow cytometry assays indicated that overexpression of ZNF424 induces apoptosis in A549 human lung carcinoma cells, and overexpression of ZNF424 significantly increases numbers of G1 phase cells and decreases numbers of S phase cells, suggesting that ZNF424 inhibits proliferation. Western Blot analyses show that overexpression of ZNF424 decreases protein expression levels of the mitogen-activated protein kinase (MAPK) signaling proteins P-P38 and P-ERK in A549 cells., Conclusion: These are the first data to associate ZNF424 with tumorigenesis and demonstrate an inhibitory role in lung cancer, indicating the potential of ZNF424 expression as a diagnostic marker of lung tumorigenesis., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

Background: Berbamine (BBM) has been reported with antitumor activities. BBM inhibited the growth of prostate cancer (PCa) cells and caused vacuolization of mitochondria in preliminary study. We hypothesized BBM could enhance apoptosis of PCa cells through mitochondrial pathway., Methods: Growth of PC-3 and LNCaP cells treated by BBM was determined by cell viability assay. The morphology of mitochondria was observed by electron microscopy. Apoptosis was quantified by flow cytometry. Expressions of bax/bcl-2, active caspase-9 and active caspase-3 were examined by western blot and real-time PCR. Methazolamide, an inhibitor of cytochrome c, was added to examine its blockade effect on BBM. PC-3 cells were injected subcutaneously into athymic mice, and BBM or saline was administrated intravenously. Diameters of induced tumors were compared, and ratios of apoptotic cells in tumor tissues were calculated., Results: BBM inhibited viability of cultured PC-3 and LNCaP cells in dose- and time-dependent manners. Flow cytometry showed BBM induced apoptosis in cultured cells. Mitochondria showed swelling, vacuolization and fused mitochondrial cristae. Western blot and real-time PCR analysis both showed increases of bax/bcl-2, active caspase-9 and active caspase-3. Methazolamide impeded effect of BBM on inducing apoptosis of cultured cells, and activations of caspase-9 and caspase-3 were also inhibited. Growth of tumors by grafted PC-3 cells was significantly slower in BBM group. Ratios of apoptotic cells in tumors were significantly higher in BBM group. Expressions of active caspase-9 and active caspase-3 in tumors were significantly upregulated by BBM., Conclusions: BBM exhibited strong anti-PCa activities in vitro and in vivo relying on activating caspase-3 via intrinsic pathway of apoptosis, holding a great promise to develop new strategies for PCa.

Objective: To study the protective effect of nuclear factor erythroid 2-related factor 2 (Nrf2) activation by curcumin against lead-induced toxicity and apoptosis in SH-SY5Y human neuroblastoma cells and its impact on expression of apoptosis-related proteins., Methods: After the cells were treated with 0, 0.5, 1, 5, or 10 μmol/L curcumin for 24 hours, nucleoprotein was extracted and electrophoretic mobility shift assay was used to measure Nrf2-antioxidant responsive element (ARE) binding capacity. The optimal concentration of curcumin was figured out for treating cells. After pretreatment with 5 μmol/L curcumin for 24 hours, cells were exposed to lead acetate at different concentrations (0, 5, 25, and 125 μmol/L for control, low-dose, medium-dose, and high-dose groups). The 3-[4, 5-dimethylthiazol-2-yl]-2, 5-diphenyl tetrazolium bromide (MTT) assay, flow cytometry, and Western blot were used to evaluate cell viability, apoptosis, and expression of apoptosis-related proteins, respectively., Results: Curcumin of 5 μmol/L caused significantly increased cell viability in low-, medium-, and high-dose groups exposed to lead acetate for 12 hours (98.42%±1.12% vs 92.92%±0.14%, P<0.05; 95.30%±1.17% vs 91.15%±0.67%, P<0.05; 94.50%±1.45% vs 85.98%±0.45%, P<0.05). Curcumin of 5 μmol/L also caused significantly increased cell viability in medium-and high-dose groups exposed to lead acetate for 24 hours (93.10%±1.63% vs 88.40%±4.13%, P<0.05; 90.13%±2.03% vs 83.63%±3.42%, P<0.05). The high-dose group had a significantly higher apoptotic rate than the control group 6.17%±1.31% vs 3.30%±0.53%, P<0.05). Curcumin of 5.0 μmol/L significantly reduced the apoptotic rate in the high-dose group (2.97%±0.15% vs 6.17%±1.31%, P<0.05). Exposure to lead acetate elevated the expression of Bax, cytochrome C, and caspase-3 and reduced Bcl-2 expression. Curcumin of 5.0 μmol/L significantly reduced the expression of Bax, cytochrome C, and caspase-3 in the high-dose group (P<0.05)., Conclusion: Nrf2 activation by curcumin has a protective effect against lead-induced toxicity and apoptosis in SH-SY5Y cells. The protective effect of Nrf2 against apoptosis may be associated with the regulation of apoptosis-related proteins.

The mechanism of chemotherapy-induced gastrointestinal (GI) syndrome (CIGIS) is still controversial, and it is unclear whether chemotherapy induces intestinal stem cell (ISC) apoptosis. β-Arrestins are regulators and mediators of G protein-coupled receptor signaling in cell apoptosis, division and growth. In this study, we aimed to investigate whether chemotherapy induces ISC apoptosis to contribute to mucositis in CIGIS and whether β-arrestin1 (β-arr1) is involved in this apoptosis. Different chemotherapeutic agents were used to generate a CIGIS model. Lgr5-EGFP-IRES-creERT2(+/-) knock-in mice were used as a CIGIS model to investigate ISC apoptosis. β-arr1 knockout mice were used to determine whether β-arr1 is involved in the apoptosis in CIGIS. Intestinal histology was performed, the ISC apoptosis was analyzed and the mucosal barrier was examined. The effects of β-arr1 in apoptosis were investigated in the samples from humans and mice as well as in cell lines. Here, we demonstrate that chemotherapy induced intestinal mucositis by promoting crypt cell apoptosis, especially in Lgr5+ stem cells and Paneth cells but not in goblet cells, epithelial cells or vascular endothelial cells. Furthermore, β-arr1 deficiency exacerbated the Lgr5+ stem cell apoptosis, but not Paneth cell apoptosis, in CIGIS. In addition, the data showed that β-arr1 reduced the chemotherapy-induced Lgr5+ stem cell apoptosis by inhibiting endoplasmic reticulum stress-mediated mitochondrial apoptotic signaling. Our study indicates that β-arr1 inhibits chemotherapy-induced ISC apoptosis to alleviate intestinal mucositis in CIGIS.

Objective: To explore the effect of down-regulated methionine synthase reductase(MTRR)gene on the apoptosis and autophagy pathway, and offer a possible approach for the MTRR to reverse the multi-resistant ovarian cancer., Methods: (1)The experiment was divided into 3 groups, SKOV3/DDP-MTRRi(down-regulated MTRR group), SKOV3/DDP-NC(negative control group), and SKOV3/DDP(blank control group). Different concentration of cisplatin(0, 1, 2, and 4 μg/ml)treated on 3 groups cells. The apoptosis rate was measured by flow cytometry(FCM). Autophagy was detected by immunofluorescence. Autophagy microtubule associated protein light chain 3β(LC3B)and p62 were detected by western blot. The formation of autophagosome of cells was observed by transmission electron microscope.(2)Detection of autophagy and apoptosis of SKOV3/DDP-MTRRi induced by rapamycin. The experiment was divided into 4 groups included rapamycin group(5 nmol/L rapamycin), rapamycin+cisplatin group(5 nmol/L rapamycin+ 4 μg/ml cisplatin), cisplatin group(4 μg/ml cisplatin)and blank control group. LC3B and p62 protein were detected by western blot. The survival rate cells were detected by methyl thiazolyl tetrazolium(MTT)method. The apoptosis rate was measured by FCM.(3)The 3 groups cells(SKOV3/DDP, SKOV3/DDP-NC and SKOV3/DDP-MTRRi)induced by a certain concentration of cisplatin(4 μg/ml)after 48 hours, then detecting the protein expression of caspase, Bcl-2 family in apoptosis pathway and the key proteins in phosphatidylinositol-3 kinase(PI3K)/protein kinase B(Akt)autophagy pathways by western blot, getting the time when the proteins' expression changed., Results: (1)The 3 groups cells(SKOV3/DDP, SKOV3/DDP-NC, and SKOV3/DDP-MTRRi)induced by a certain concentration of cisplatin(4 μg/ml)after 48 hours, apoptosis and autophagy of 3 groups of cells were gradually increased with the increased concentration of cisplatin. The apoptosis rate of SKOV3/DDP-MTRRi cells[(26.2 ± 1.4)%]were significantly increased compared with the SKOV3/DDP-NC cells or SKOV3/DDP cells[(14.8±2.4)%,(14.2±2.4)%; all P<0.05]at 2 μg/ml cisplatin. Immunofluorescence tests revealed that the aggregates of LC3B in SKOV3/DDP-MTRRi cells were more than that of SKOV3/DDP-NC cells and SKOV3/DDP cells. The expression of LC3B of SKOV3/DDP-MTRRi cells was lower than those of SKOV3/DDP-NC cells and SKOV3/DDP cells(P<0.05). The expression of p62 of SKOV3/DDP-MTRRi cells was higher than those of SKOV3/DDP-NC cells and SKOV3/DDP cells(P<0.05). The structure of chloroplast was integrity and autophagosome was dispersing in plastids of SKOV3/DDP-NC cells and SKOV3/DDP cells. Organelles disappear and vacuoles increased obviously in SKOV3/DDP-MTRRi cells, no autophagosome was observed.(2)The expression of LC3B of rapamycin + cisplatin group was higher than those of other 3 group cells(1.72±0.08, 1.43±0.04, 1.37±0.11, and 1.11±0.09; P<0.05). The expression of p62 of rapamycin + cisplatin group was significant decreased(0.58 ± 0.10, 0.94 ± 0.12, 1.21 ± 0.11, and 1.57 ± 0.10; P<0.05). The survival rate of rapamycin + cisplatin group was higher than that of cisplatin group[(0.78±0.03)% vs(0.62±0.03)%; P=0.018], the apoptosis rate was significant decreased in rapamycin+ cisplatin group[(59.0 ± 3.9)% vs(40.4 ± 3.0)%, P=0.019].(3)The 3 groups cells(SKOV3/DDP, SKOV3/DDP-NC, and SKOV3/DDP-MTRRi)induced by a certain concentration of cisplatin(4 μg/ml)after 48 hours, the expression of Bax in 3 groups cell were not evidently changed(P= 0.661). The expression of Bcl-2 was significantly decreased in SKOV3/DDP-MTRRi cells(P=0.030). The expression of caspase-3, caspase-7, caspase-9, and poly(ADP-ribose)polymerase(PARP)were not evidently changed(P>0.05), but cleaved caspase-3, cleaved caspase-7, cleaved caspase-9, and cleaved PARP were significantly increased in SKOV3/DDP-MTRRi cells(P<0.05). For the autophagy pathway, the expression of phosphorylated Akt(p-Akt)and phosphorylated mammalian target of rapamycin(p-mTOR)were significantly increased(P <0.05), but Akt and mTOR had no significant variation. The expression of phosphatase and tensin homologue deleted on chromosome ten(PTEN)was significantly decreased(P <0.05)., Conclusions: MTRR silencing significantly increase cisplatin-induced apoptosis and reduce the autophagy induced by cisplatin in SKOV3/DDP cells. Down-regulation of MTRR enhanced the chemosensitivity of cisplatinresistant ovarian cancer cells may be by activating caspase and Bcl-2 apoptosis family and inhibiting the PI3K/Akt autophagy pathway.

Background and Objective: Hepatocellular carcinoma (HCC) is the second leading cause of cancer death worldwide. Genotoxic stress resistance in patients often contributes to poor clinical outcomes, and is intensively associated to the upregulation of Nrf2/ARE signaling pathway. In this study, we examined the connection between the anticancer activity of two novel indazolo[3,2-b]quinazolinone (IQ) derivatives, IQ-7 and IQ-12, and their effect on the Nrf2/ARE signaling pathway., Methods: We initially measured the cytotoxicity of IQ-7 and IQ-12 in Hep3B (human hepatoma cell) and HL-7702 (normal human liver cell) cell lines, then further detected their effects on Nrf2/ARE signaling pathway and apoptosis., Results: IQ-7 and IQ-12 downregulated the expression levels of Nrf2 and its downstream target genes, such as NQO1, HO-1 and Gclc. In Hep3B cells treated with IQ-7 or IQ-12, the mitochondrial membrane potential decreased dramatically while the expression level of the pro-apoptotic protein VDAC1 and anti-apoptotic protein Bcl-2 significantly increased and decreased, respectively. In addition, IQ-7 (but not IQ-12) also induced the activity of Caspase-3. Interestingly, IQ-7 appeared to selectively inhibit Hep3B cells while having rare adverse effect on HL-7702 cells., Conclusion: The two compounds were shown to induce apoptosis and inhibit the Nrf2/ARE signaling pathway in Hep3B cells, and IQ-7 was suggested a degree of specificity against cancer cells. The design of these compounds may therefore represent a new strategy for designing quinazoline derivatives that could selectively target carcinoma cells., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.)

Milk fat globule epidermal growth factor 8 (MFG-E8) is an opsonin involved in the phagocytosis of apoptotic cells. In patients with chronic obstructive pulmonary disease (COPD), apoptotic cell clearance is defective. However, whether aberrant MFG-E8 expression is involved in this defect is unknown. In this study, we examined the expression of MFG-E8 in COPD patients. MFG-E8, interleukin (IL)-1β and transforming growth factor (TGF)-β levels were measured in the plasma of 96 COPD patients (93 males, 3 females; age range: 62.12±10.39) and 87 age-matched healthy controls (85 males, 2 females; age range: 64.81±10.11 years) using an enzyme-linked immunosorbent assay. Compared with controls, COPD patients had a significantly lower plasma MFG-E8 levels (P<0.01) and significantly higher plasma TGF-β levels (P=0.002), whereas there was no difference in plasma IL-1β levels between the two groups. Moreover, plasma MFG-E8 levels decreased progressively between Global Initiative for Chronic Obstructive Lung Disease (GOLD) I and GOLD IV stage COPD. Multiple regression analysis showed that the forced expiratory volume in 1 s (FEV1 % predicted) and smoking habit were powerful predictors of MFG-E8 in COPD (P<0.01 and P=0.026, respectively). MFG-E8 was positively associated with the FEV1 % predicted and negatively associated with smoking habit. The area under the receiver operating characteristic curve was 0.874 (95% confidence interval: 0.798-0.95; P<0.01). Our findings demonstrated the utility of MFG-E8 as a marker of disease severity in COPD and that cigarette smoke impaired MFG-E8 expression in these patients.

Background: The activation of renin angiotensin system is involved in multiple pathological processes. The neuroprotective effect of propofol has been reported. We hypothesized that propofol may attenuate Angiotensin II (Ang II)-induced apoptosis in mouse hippocampal HT22 cells and aimed to identify the underlying mechanisms., Methods: Mouse hippocampal HT22 cells were pre-treated with propofol, and stimulated with Ang II. Apoptosis was examined by transferase dUTP nick end labeling (TUNEL) staining and caspase-3 activity assay. The effect of propofol on Ang II-modulated neuronal nitric oxide synthase (nNOS) expression, nitric oxide (NO) production, nicotinamide adenine dinucleotide phosphate (NADPH) oxidase expression and activity, caspase activity and metallothinonein-3 (MT-3) expression were measured., Results: Compared with control, Ang II concentration- and time-dependently induced apoptosis, which was attenuated by propofol in a concentration-dependent manner. Ang II (1 μM, 3 h) induced the expression of nNOS and NADPH oxidase, caused NO and superoxide anion accumulation, thus leading to excessive oxidative stress. Ang II also induced cytochrome C release and the activation of caspase 9 as well as caspase 3. In addition, Ang II reduced the expression of MT-3. Importantly, these effects were alleviated by 50 μM propofol, nNOS inhibitor S-methyl-l-thiocitrulline (SMTC) and angiotensin type 1 receptor (AT1R) blocker losartan, but not AT2R blocker PD123319., Conclusions: Ang II via AT1R induced oxidative stress and apoptosis in hippocampal HT22 cells, and the neuroprotective anti-apoptotic effect of propofol was mediated through inhibiting oxidative stress., (Copyright © 2015 IBRO. Published by Elsevier Ltd. All rights reserved.)

We examined the influence of cyclophilin-D (CypD) protein expression level on endothelial cell oxidative damage resistance. A model of CypD protein expression or high expression in endothelial cells was established through gene silencing or cloning. The comparable groups were normal endothelial cells cultured in phosphate-buffered solution in liquid handling cells containing 500 mM H2O2 for 90 or 120 min, and then the medium was replaced with common nutrient solution and cultured again for 24 h. The apoptosis rate and nitric oxide (NO) levels of each group were tested. The cell apoptosis rate of the CyPD low expression group (32.51 ± 6.6 %) was significantly lower than that of the control group (52.57 ± 5.84%, P = 0.001), and total NO production was 24.06 ± 3 and 13.03 ± 3.55 μM. The apoptosis rate of the CyPD high expression group (24.24 + 3.08%) was significantly higher than that of the control group (7.7 + 0.68%, P < 0.001); total NO production was 3.55 ± 1.53 and 8.46 ± 0.77 μM, which was significantly different (P = 0.008). CypD protein could increase oxidative stress and cause endothelial cell injury and apoptosis.

The anti-apoptotic protein MCL-1 is a key regulator of cancer cell survival and a known resistance factor for small-molecule BCL-2 family inhibitors such as ABT-263 (navitoclax), making it an attractive therapeutic target. However, directly inhibiting this target requires the disruption of high-affinity protein-protein interactions, and therefore designing small molecules potent enough to inhibit MCL-1 in cells has proven extremely challenging. Here, we describe a series of indole-2-carboxylic acids, exemplified by the compound A-1210477, that bind to MCL-1 selectively and with sufficient affinity to disrupt MCL-1-BIM complexes in living cells. A-1210477 induces the hallmarks of intrinsic apoptosis and demonstrates single agent killing of multiple myeloma and non-small cell lung cancer cell lines demonstrated to be MCL-1 dependent by BH3 profiling or siRNA rescue experiments. As predicted, A-1210477 synergizes with the BCL-2/BCL-XL inhibitor navitoclax to kill a variety of cancer cell lines. This work represents the first description of small-molecule MCL-1 inhibitors with sufficient potency to induce clear on-target cellular activity. It also demonstrates the utility of these molecules as chemical tools for dissecting the basic biology of MCL-1 and the promise of small-molecule MCL-1 inhibitors as potential therapeutics for the treatment of cancer.

Objective: To examine the expression of bone sialoprotein (BSP) and apoptosis in an in vivo orthodontic relapse model., Materials and Methods: Male mice (10-12 weeks old), either transgenic [green fluorescent protein (GFP) driven by the BSP promoter] or wild type, were used in this study. To achieve orthodontic tooth movement (OTM), maxillary right first molars were moved mesially using closed-coil springs. Animals were divided into an OTM group (14 days continuous orthodontic force - 11 animals) or Relapse group (10 days of force application followed by 4 days of relapse - 8 animals). The control group was comprised of the contralateral maxillary molars. The periodontal ligament (PDL) was analyzed in areas of compression and tension for transgenic expression, osteoclast localization, and the presence of apoptotic cells., Results: There was a significant decrease in GFP-labeled cells on the compression and tension sides of the PDL in the OTM group compared with control. In the relapse group, GFP-labeled cells were significantly decreased only on the old compression side. Osteoclasts were localized on the compression side of the OTM group, whereas in the Relapse group, they were present on both sides. PDL apoptosis significantly increased on the compression side in OTM and Relapse groups., Conclusion: Both OTM and Relapse groups exhibited a decreased number of GFP-labeled cells in areas of compression and tension. There was significant PDL apoptosis in regions under compressive forces following OTM and to a lesser extent following relapse., (© 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.)

Matrine, a main active extract from Sophora flavescens Ait, has been demonstrated to exert anticancer effects on various cancer cell lines, such as malignant melanoma, breast cancer, and lung cancer. However, it is currently unclear whether matrine could also elicit an inhibitory effect on growth of nasopharyngeal carcinoma (NPC), let alone the possible molecular mechanisms. Therefore, in a previous study, we investigated matrine-induced proliferation inhibition and apoptosis in NPC cells. It was shown that proliferation of human NPC cells (CNE1 and CNE2) was significantly diminished by matrine in a dose- and time-dependent manner, and apoptosis was induced in both 2 NPC cells, particularly in CNE2 cells. Moreover, the increased apoptosis rate in matrine-treated CNE2 cells confirmed the proapoptotic activity of matrine. We further found that matrine treatment dose- and time-dependently reduced the levels of vascular endothelial growth factor-A (VEGF-A), and inactivated extracellular signal-regulated kinase1/2 (ERK1/2), followed by increased expression of downstream target caspase-3. Overall, we conclude that matrine could induce apoptosis of human NPC cells via VEGF-A/ERK1/2 pathway, which supports the potential use of matrine in clinically treating NPC., (© Georg Thieme Verlag KG Stuttgart · New York.)

Objectives: Enhancer of zeste homologue 2 (EZH2) is crucially involved in epigenetic silencing by acting as a histone methyltransferase. Although EZH2 is overexpressed in many cancers and is involved in malignant cell proliferation and invasion, the role of EZH2 in senescence induced by DNA damage has up to now remained largely unknown. In this study, we sought to explore the outcome of EZH2 depletion along with exposure of doxorubicin (DOX), and related mechanisms, in gastric cancer cells., Materials and Methods: Here, senescence induced by DNA damage was achieved in gastric cancer cells by DOX treatment. EZH2 was downregulated by transfection with siRNA or treated with (-)-epigallocatechin-3-gallate, a targeted inhibitor. Senescence-associated β galactosidase (SA-β-gal) and formation of senescence-associated heterochromatin foci were used to identify cell senescence. To investigate effects of EZH2 depletion on the cell cycle, apoptosis and proliferation, flow cytometry and MTT analysis were employed. Changes in p53-p21 axis activation were detected by Western blotting., Results: We found that cell proliferative arrest caused by DOX could be promoted by EZH2 depletion. Mechanistically, EZH2 depletion not only worked in coordination with DNA damage during the progression of cell senescence but also promoted apoptosis in p53 mutant cells. However, it had no cooperative relationship with DOX in p53 wild-type cells., Conclusions: These data help unravel a crucial role for EZH2 in senescence and apoptosis in gastric cancer cells and that p53 genomic status was associated with different cell responses to EZH2 silencing., (© 2014 John Wiley & Sons Ltd.)

Therapeutic options for hypoxic-ischemic brain damage (HIBD) are scarce and inefficient. Recently, many studies have demonstrated that red photon plays an important role in anti-inflammatory processes as well as apoptosis, the main trait of HIBD. In this study, we investigated whether red photon can protect from HIBD in SD rats and oxygen-glucose deprivation (OGD) in PC12 cells. Apoptosis, mitochondrial transmembrane potential (MMP), and reactive oxygen species (ROS) rates were assessed in PC12 cells. We found that 6-h irradiation resulted in decreased MMP, ROS and apoptosis rates, although these changes were reversible with prolonged irradiation. Importantly, these effects were sustained for 2-8h upon quenching of the red photon. Similar trends were observed for protein and mRNA expression of bax and bcl-2, with short-term irradiation (6h) inhibiting apoptosis in PC12 Cells. However, long-term (>6h) irradiation caused cell damage. In vivo experiments, bax mRNA and protein levels were reduced after 7days in HIBD model rats treated with red photon, in contrast to bcl-2. Furthermore, we found that bax and bcl-2 were mainly expressed in pyramidal cells of the hippocampus CA1 and CA3. Importantly, Morris Water Maze test results revealed an improvement in learning ability and spatial memory in rats after irradiation. Overall, our data showed that short-term irradiation with red photon in the acute phase inhibits the mitochondrial apoptotic pathway via regulation of bcl-2-related proteins and reduction of ROS levels, thereby decreasing apoptosis in nerve cells and improving the neurological prognosis of HIBD., (Copyright © 2014 IBRO. Published by Elsevier Ltd. All rights reserved.)

Receptor-interacting protein (RIP) kinases promote the induction of necrotic cell death pathways. Here we investigated signaling pathways in outer hair cells (OHCs) of adult male CBA/J mice exposed to noise that causes permanent threshold shifts, with a particular focus on RIP kinase-regulated necroptosis. One hour after noise exposure, nuclei of OHCs in the basal region of the cochlea displayed both apoptotic and necrotic features. RIP1 and RIP3 protein levels increased and caspase-8 was activated. Treatment with pan-caspase inhibitor ZVAD blocked the activation of caspase-8 and reduced the number of apoptotic nuclei, while increasing levels of RIP1, RIP3, and necrotic OHCs. Conversely, treatment with necrosis inhibitor necrostatin-1 (Nec-1) or RIP3 siRNA (siRIP3) diminished noise-induced increases in RIP1 and RIP3, and decreased necrotic OHC nuclei. This treatment also increased the number of apoptotic nuclei without increasing activation of caspase-8. Consistent with the elevation of levels of RIP1 and RIP3, noise-induced active AMPKα levels increased with ZVAD treatment, but decreased with Nec-1 and siRIP3 treatment. Furthermore, treatment with siRIP3 did not alter the activation of caspase-8, but instead increased activation of caspase-9 and promoted endonuclease G translocation into OHC nuclei. Finally, auditory brainstem response functional measurements and morphological assessment of OHCs showed that ZVAD treatment reduces noise-induced deficits. This protective function is potentiated when combined with siRIP3 treatment. In conclusion, noise-induced OHC apoptosis and necrosis are modulated by caspases and RIP kinases, respectively. Inhibition of either pathway shifts the prevalence of OHC death to the alternative pathway.

Disturbance of endoplasmic reticulum (ER) homeostasis causes ER stress and leads to activation of the unfolded protein response, which reduces the stress and promotes cell survival at the early stage of stress, or triggers cell death and apoptosis when homeostasis is not restored under prolonged ER stress. Here, we report that Cab45S, a member of the CREC family, inhibits ER stress-induced apoptosis. Depletion of Cab45S increases inositol-requiring kinase 1 (IRE1) activity, thus producing more spliced forms of X-box-binding protein 1 mRNA at the early stage of stress and leads to phosphorylation of c-Jun N-terminal kinase, which finally induces apoptosis. Furthermore, we find that Cab45S specifically interacts with 78-kDa glucose-regulated protein/immunoglobulin heavy chain binding protein (GRP78/BiP) on its nucleotide-binding domain. Cab45S enhances GRP78/BiP protein level and stabilizes the interaction of GRP78/BiP with IRE1 to inhibit ER stress-induced IRE1 activation and apoptosis. Together, Cab45S, a novel regulator of GRP78/BiP, suppresses ER stress-induced IRE1 activation and apoptosis by binding to and elevating GRP78/BiP, and has a role in the inhibition of ER stress-induced apoptosis.

The diterpene triepoxide triptolide is a major active component of Tripterygium wilfordii Hook F, a popular Chinese herbal medicine with the potential to treat hematologic malignancies. In this study, we investigated the roles of triptolide in apoptosis and cell signaling events in human leukemia cell lines and primary human leukemia blasts. Triptolide selectively induced caspase-dependent cell death that was accompanied by the loss of mitochondrial membrane potential, cytochrome c release, and Bax translocation from the cytosol to the mitochondria. Furthermore, we found that triptolide dramatically induced ROCK1 cleavage/activation and MLC and MYPT phosphorylation. ROCK1 was cleaved and activated by caspase-3, rather than RhoA. Inhibiting MLC phosphorylation by ML-7 significantly attenuated triptolide-mediated apoptosis, caspase activation, and cytochrome c release. In addition, ROCK1 inhibition also abrogated MLC and MYPT phosphorylation. Our in vivo study showed that both ROCK1 activation and MLC phosphorylation were associated with the tumor growth inhibition caused by triptolide in mouse leukemia xenograft models. Collectively, these findings suggest that triptolide-mediated ROCK1 activation and MLC phosphorylation may be a novel therapeutic strategy for treating hematological malignancies.

Our previous studies have shown that the inhibition of phosphatidylinositol 3-kinase (PI3K) or mTOR complex 1 can obviously promote the Coxsackievirus B3 (CVB3)-induced apoptosis of HeLa cells by regulating the expression of proapoptotic factors. To further illustrate it, Homo sapiens eIF4E-binding protein 1 (4EBP1), p70S6 kinase (p70S6K), Akt1 and Akt2 were transfected to HeLa cells, respectively. And then, we established the stable transfected cell lines. Next, after CVB3 infection, apoptosis in different groups was determined by flow cytometry; the expressions of Bim, Bax, caspase-9 and caspase-3 were examined by real-time fluorescence quantitative PCR and western blot analysis; the expression of CVB3 mRNA and viral capsid protein VP1 were also analyzed by real-time fluorescence quantitative PCR, western blot analysis and immunofluorescence, respectively. At the meantime, CVB3 replication was observed by transmission electron microscope. We found that CVB3-induced cytopathic effect and apoptosis in transfected groups were more obvious than that in controls. Unexpectedly, apoptosis rate in Akt1 group was higher than others at the early stage after viral infection and decreased with the viral-infected time increasing, which was opposite to other groups. Compared with controls, the expression of CVB3 mRNA was increased at 3, 6, 12 and 24 h postinfection (p. i.) in all groups. At the meantime, VP1 expression in 4EBP1 group was higher than control during the process of infection, while the expressions in the other groups were change dynamically. Moreover, overexpression of 4EBP1 did not affect the mRNA expressions of Bim, Bax, caspase-9 and caspase-3; while protein expressions of Bim and Bax were decreased, the self-cleavages of caspase-9 and caspase-3 were stimulated. Meanwhile, overexpression of p70S6K blocked the CVB3-induced Bim, Bax and caspase-9 expressions but promoted the self-cleavage of caspase-9. In the Akt1 group, it is noteworthy that the expressions of Bim protein were higher than controls at 3 and 6 h p. i. but lower at 24 h p. i., and the expression of Bax protein were higher at 6 and 24 h p. i., while their mRNA expressions were all decreased. Furthermore, overexpression of Akt1 stimulated the procaspase-9 and procaspase-3 expression but blocked their self-cleavages. Overexpression of Akt2, however, had little effect on Bim, Bax and caspase-3, while prevented caspase-9 from self-cleavage at the late stage of CVB3 infection. As stated above, our results demonstrated that overexpression of 4EBP1, p70S6K, Akt1 or Akt2 could promote the CVB3-induced apoptosis in diverse degree via different mediating ways in viral replication and proapoptotic factors in BcL-2 and caspase families. As 4EBP1, p70S6K and Akt are the important substrates of PI3K and mammalian target of rapamycin (mTOR), we further illustrated the role of PI3K/Akt/mTOR signaling pathway in the process of CVB3-induced apoptosis.

Breast cancer is a leading cause of cancer death among women, and the failure of normal apoptosis has been proved in the development of breast cancer. The phytoestrogen, calycosin, is extracted from Chinese medical herb Radix astragali. We recently reported that calycosin successfully stimulated proliferation of ER-positive MCF-7 human breast cancer cells at low concentration. In the present study, we assessed the proapoptotic function of calycosin in MCF-7 cells at high concentration in vitro, as well as the possible mechanism of its effect. MCF-7 cells were treated with different concentrations of calycosin, and then detected by MTT assay for cellular viability, Hoechst assay, and flow cytometry for apoptosis. RASD1 is identified as a Ras-family member and a regulator in MAPK-mediated cascade leading to cell proliferation or apoptosis. To provide insight into the functions of RASD1 signaling pathway in calycosin-induced apoptosis, the expression of Bcl-2, Bax, and RASD1 in calycosin-treated cells were determined by Western blot assay. The results showed that high concentrations of calycosin significantly suppressed the proliferation of MCF-7 cells and promoted cell apoptosis. Moreover, compared with control group, the expression of Bcl-2 decreased with calycosin in MCF-7 cells, while Bax increased, which was significantly correlated with elevated expression of RASD1. Together, we present evidence that at relatively high concentration calycosin triggered cell apoptosis through the mitochondrial apoptotic pathway by upregulating RASD1. And for the first time, this study revealed that calycosin may have potential as a therapeutic agent for the treatment of breast cancer., (© Georg Thieme Verlag KG Stuttgart · New York.)

Background and Aim: Propofol is one of the most commonly used intravenous anaesthetic agents during cancer resection surgery. It has recently found that propofol has the effect to inhibit cancer cell migration and invasion and sensitize cancer cells to chemotherapy. However, the role of the propofol on the ovarian cancer cells is unknown. In the present study, we explored the effect of propofol on invasion and chemosensitization of ovarian cancer cells to paclitaxel., Materials and Methods: The paclitaxel sensitivity of ovarian cancer cell lines HO-8910PM, H0-8910, SKOV-3, OVCAR-3, COC1 and ES-2 were determined by MTT assays. The Slug levels in the cell lines and the effects of propofol on Slug levels in the cell lines were determined by western blot assays. The effect of propofol on invasion, migration and paclitaxel-induced ovarian cancer apoptosis was determined by Boyden chamber assays, cell MTT, TUNEL assays., Results: The results showed that the cell lines COC1, H0-8910 and ES-2 were sensitive, whereas HO-8910PM, OVCAR-3, SKOV-3, were resistant to paclitaxel. Significant correlation was observed between basal Slug levels and paclitaxel sensitivity. Paclitaxel treatment increased Slug levels. Treatment with propofol induced apoptosis and increased paclitaxel killing of all paclitaxel-sensitive and -resistant ovarian cancer cells followed by significant decrease in the Slug levels. Treatment with propofol inhibits invasion and migration., Conclusions: These data suggest a new mechanism by which the propofol inhibits invasion and metastasis,enhances paclitaxel-induced ovarian cancer cell apoptosis through suppression of Slug.

Benzyl isothiocyanate (BITC) is one of the compounds of ITCs' family that has attracted a great deal of interest because of its ability to exhibit anticancer activity. In this study, we investigated the effects of BITC on cell cycle arrest and apoptosis in human leukemia cell lines, primary leukemia cells, and nude mice Jurkat xenograft. Exposure of Jurkat cells to BITC resulted in dose- and time-dependent increase in apoptosis, caspase activation, cytochrome c release, nuclear apoptosis-inducing factor (AIF) accumulation, Bcl2-associated X protein (Bax) translocation, and myeloid cell leukemia-1 (Mcl-1) downregulation. Treatment with these cells also resulted in cell cycle arrest at the G2/M phase. The G2/M-arrested cells are more sensitive to undergoing Mcl-1 downregulation and apoptosis mediated by BITC. BITC downregulates Mcl-1 expression through inhibition of translation, rather than through a transcriptional, post-translational, or caspase-dependent mechanism. Dephosphorylation of eukaryotic initiation factor 4G could contribute to the inhibition of Mcl-1 translation mediated by BITC. Furthermore, ectopic expression of Mcl-1 substantially attenuates BITC-mediated lethality in these cells, whereas knockdown of Mcl-1 through small interfering RNA significantly enhances BITC-mediated lethality. Finally, administration of BITC markedly inhibited tumor growth and induced apoptosis in Jurkat xenograft model in association with the downregulation of Mcl-1. Taken together, these findings represent a novel mechanism by which agents targeting Mcl-1 potentiate BITC lethality in transformed and primary human leukemia cells and inhibitory activity of tumor growth of Jurkat xenograft model.

As an essential component of eukaryotic cells, the nuclear envelope (NE) plays a crucial role in many physiological processes. At present, a few membrane proteins from NE have been functionally characterized. To determine whether the inner nuclear membrane (INM) protein Nurim is expressed in cancer cells with evidence of apoptosis, we identified three isoforms of this protein that are specific for human testicular seminoma and are generated by alternative splicing. We observed that Nurim is expressed in a broad range of cancer types and that its expression level is correlated with a higher tumor grade. Biochemical analysis showed that Nurim b, like a, is tightly bound to the nuclear envelope. Furthermore, knockdown using miR-Nurim resulted in an abnormal shape change of the nuclear envelope. Notably, Nurim knockdown obviously increased apoptosis induced by ultraviolet in HeLa cells. Together, these findings implicate that the INM protein Nurim plays an important role in the suppression of apoptosis.

Formononetin is one of the main active components of red clover plants, and considered as a phytoestrogen. Its pharmacological effects in vivo may be either estrogenic or anti-estrogenic, mainly depending upon the estrogen levels. Our recent studies suggested that formononetin inactivated IGF1/IGF1R-PI3K/Akt pathways and decreased cyclin D1 mRNA and protein expression in human breast cancer cells in vitro and in vivo. In the present study, we further investigated the molecular mechanisms involved in the induced apoptosis effect of formononetin on breast cancer cells. Our results suggested that formononetin inhibited the proliferation of ER-positive MCF-7 cells and T47D cells. In contrast, formononetin could not inhibit the cell of growth of ER-negative breast cancer cells such as MDA-MB-435 S cells. We further found that formononetin activated MAPK signaling pathway in a dose-dependent manner, which resulted in the increased ratio of Bax/Bcl-2, and induced apoptosis on MCF-7 cells. However, when MCF-7 cells were pretreated with p38MAPK inhibitor SB203580 before formononetin, apoptosis induced by formononetin was significantly attenuated. Thus, we conclude that the induced apoptosis effect of formononetin on human breast cancer cells were related to Ras-p38MAPK pathway. Considering that red clover plants are widely used clinically, our results provide the foundation for future development of formononetin for treatment of ER-positive breast cancer., (© Georg Thieme Verlag KG Stuttgart · New York.)

Glioma is the most common and fatal primary brain tumor. Thus far, therapeutic strategies to efficiently and specifically antagonize glioma are limited and poorly developed. Here we report that glia-enriched miR-135a, a microRNA that is dramatically downregulated in malignant glioma and correlated with the pathological grading, is capable of inducing mitochondria-dependent apoptosis of malignant glioma by regulating various genes including STAT6, SMAD5 and BMPR2, as well as affecting the signaling pathway downstream. Moreover, this lethal effect is selectively towards malignant glioma cells, but not neurons and glial cells, through a novel mechanism. Our findings suggest an important role of miR-135a in glioma etiology and provide a potential candidate for malignant glioma therapy.

Formononetin is a main active component of red clover plants (Trifolium pratense L.), and is considered as a phytoestrogen. Our previous studies demonstrated that formononetin caused cell cycle arrest at the G0/G1 phase by inactivating insulin-like growth factor 1(IGF1)/IGF1R-phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) pathway in MCF-7 cells. In the present study, we investigated the molecular mechanisms involved in the effect of formononetin on prostate cancer cells. Our results suggested that higher concentrations of formononetin inhibited the proliferation of prostate cancer cells (LNCaP and PC-3), while the most striking effect was observed in LNCaP cells. We further found that formononetin inactivated extracellular signal-regulated kinase1/2 (ERK1/2) mitogen-activated protein kinase (MAPK) signaling pathway in a dose-dependent manner, which resulted in increased the expression levels of BCL2-associated X (Bax) mRNA and protein, and induced apoptosis in LNCaP cells. Thus, we concluded that the induced apoptosis effect of formononetin on human prostate cancer cells was related to ERK1/2 MAPK-Bax pathway. Considering that red clover plants were widely used clinically, our results provided the foundation for future development of different concentrations formononetin for treatment of prostate cancer., (© Georg Thieme Verlag KG Stuttgart · New York.)

Silibinin, an effective anti-cancer and chemopreventive agent in various epithelial cancer models, has been reported to inhibit cancer cell growth through mitogenic signalling pathways including cervical cancer. However, the underlying mechanisms are still not well elucidated. Here, we assessed the effect of silibinin on human cervical carcinoma cell cycle modulation, apoptosis induction and associated molecular alterations by employing HeLa cell line. Silibinin treatment of HeLa cells resulted in a G2 arrest and induced a decrease in cyclin-dependent kinases involved in both G1 and G2 progression. In addition, silibinin showed a dose-dependent and a time-dependent apoptotic death in HeLa cells in both the mitochondrial pathway and the death receptor-mediated pathway, providing a strong rationale for future studies evaluating preventive and/or intervention strategies for silibinin in cervical cancer pre-clinical models., (Copyright © 2011 John Wiley & Sons, Ltd.)

Tupistra chinensis Baker has been used as a folk remedy in China, and it has been shown to exhibit anti-inflammation, expectorant and anti-bacterial effects. In this study, we report the cytotoxic activity of the total saponins of Tupistra chinensis Baker (TST) against several carcinoma cell lines, including A549, MCF-7 and HeLa cells with the IC50 values of 4.11 μg/ml, 6.47 μg/ml and 7.78 μg/ml respectively. Treatment of A549 cells with TST resulted in growth inhibition and induction of apoptosis in a time-dependent manners determined by cell viability, chromatin condensation, DNA fragmentation and flow cytometry analysis. The activities of caspase-3, 9 were significantly increased following TST treatment. Real-time PCR analysis showed that the mRNA expression levels of pro-apoptosis related genes including Bax, P21, P27 and P53 were markedly increased in the cells treated with TST but anti-apoptosis related gene Bcl-2 was slightly decreased. TST also leads to a loss of mitochondrial membrane potential in a time-dependent manner the release of cytochrome C from mitochondria into the cytosol. Thus, these results suggest that TST may play an important role in tumor growth suppression by inducing apoptosis in human A549 cells via mitochondria-dependent apoptotic pathways and the TST would be promising to treat human lung adenocarcinoma.

Calbindin-D28k (CaBP) has a neuroprotective effect on dopaminergic (DA) neurons in several models of Parkinson's disease. We used the DA cell line MN9D to explore the mechanisms underlying CaBP-mediated protection against the neurotoxin 6-hydroxydopamine (6-OHDA) of DA neurons. In MN9D cells that were transfected with the expression vector pcDNA3-CB containing CaBP cDNA, the expression level of CaBP was significantly increased. After treating with 6-OHDA, a significant decrease in the apoptosis rate of the transfected MN9D cells was noted, as well as an obvious increase in the expression of phosphorylation of Akt (p-Akt); however, no significant change in the expression of total Akt or phospho-p100 (p-p100) occurred after this treatment. After treatment with wortmannin, an inhibitor of the PI3-kinase-Akt (PI-3K/Akt) signal pathway, an increase in the expression level of CaBP was observed, but there were no other obvious changes of the experimental index mentioned previously in the groups transfected with pcDNA3-CB. These studies suggest that CaBP has a significant role in protecting DA cells against the apoptosis induced by 6-OHDA--through PI-3K/Akt signaling pathway--where the non-canonical nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) signaling pathway might have no relevance., (Copyright © 2011 IBRO. Published by Elsevier Ltd. All rights reserved.)

Background: Angiotensin II (Ang II) induces oxidative stress and apoptosis in vascular endothelial cells. We hypothesized that propofol may attenuate Ang II-induced apoptosis in human coronary artery endothelial cells (HCAECs) and aimed to identify the underlying mechanisms., Methods: Endothelial cells were pre-treated with propofol and then stimulated with Ang II. Apoptosis was examined by TUNEL, DNA laddering, and caspase-3 activity assays. The effect of propofol on Ang II-modulated NADPH oxidase expression and activity, nitric oxide synthase III (NOSIII) expression and phosphorylation and activity, lipid peroxidation, superoxide anion generation, nitric oxide production, caspase activity, and protein expression of cytochrome c, Bcl-2, and C-IAP-1 were measured., Results: Ang II induced apoptosis, which was attenuated by 50 µM propofol (P<0.05). Propofol ameliorated Ang II-induced NADPH oxidase expression and activation (P<0.01), lipid peroxidation (P<0.05), and superoxide anion generation (P<0.05), whereas restoring NOSIII phosphorylation and activity (P<0.01) were down-regulated by Ang II. Propofol attenuated Ang II-modulated cytochrome c release, and the expression of Bcl-2 and C-IAP-1. In addition, propofol inhibited Ang II-induced caspase-9 (P<0.01) and caspase-3 activity (P<0.01)., Conclusions: Propofol protected HCAECs from Ang II-induced apoptosis by interfering with the generation of oxidative stress and redox-sensitive apoptotic pathways.

Vasopressin (VP) secreted within the brain modulates neuronal function by acting as a neurotransmitter. Recent studies show that VP prevents serum deprivation-induced apoptosis in the neuronal cell line, H32. To determine whether VP is anti-apoptotic in hippocampal neurones, primary cultures of these neurones were used to examine the effect of VP on neuronal culture supplement (B27) deprivation-, or glutamate-induced apoptosis, and the signalling pathways mediating the effects. Removal of B27 supplement from the culture medium for 24 h or the addition of glutamate (3-10μm) decreased neuronal viability (P<0.05) and increased Tdt-mediated dUTP nick-end labelling (TUNEL) staining and caspase-3 activity (P<0.05), which is consistent with apoptotic cell death. VP (10 nm) reduced B27 deprivation- or glutamate-induced cell death (P<0.05). These anti-apoptotic effects of VP were completely blocked by a V1 but not a V2 receptor antagonist, indicating that they are mediated via V1 VP receptors. The anti-apoptotic effect of VP in neurones involves activation of mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) and inositol trisphosphate/protein kinase B (Akt) signalling pathways. This was shown by the transient increases in phospho-ERK and phospho-Akt after incubation with VP revealed by western blot analyses, and the ability of specific inhibitors to reduce the inhibitory effect of VP on caspase-3 activity and TUNEL staining by 70% and 35%, respectively (P<0.05). These studies demonstrate that VP has anti-apoptotic actions in hippocampal neurones, an effect that is mediated by the MAPK/ERK and phosphatidylinositol-3 kinase/Akt signalling pathways. The ability of VP to reduce nutrient deprivation or glutamate overstimulation-induced neuronal death suggests that VP acts as a neuroprotective agent within the brain., (Journal of Neuroendocrinology © 2010 Blackwell Publishing Ltd. No claim to original US government works.)

Background and Objectives: Mesenchymal stem cells (MSC) are multipotent progenitor cells that are have found use in regenerative medicine. We have previously observed that aspirin, a widely used anti-inflammatory drug, inhibits MSC proliferation. Here we have aimed to elucidate whether aspirin induces MSC apoptosis and whether this is modulated through the Wnt/beta-catenin pathway., Materials and Methods: Apoptosis of MSCs was assessed using Hoechst 33342 dye and an Annexin V-FITC/PI Apoptosis Kit. Expression of protein and protein phosphorylation were investigated using Western blot analysis. Caspase-3 activity was detected by applying a caspase-3/CPP32 Colorimetric Assay Kit., Results: In these MSCs, aspirin induced morphological changes characteristic of apoptosis, cytochrome c release from mitochondria, and caspase-3 activation. Stimulating the Wnt/beta-catenin pathway by both Wnt 3a and GSK-3beta inhibitors (LiCl and SB 216763), blocked aspirin-induced apoptosis and protected mitochondrial function, as demonstrated by decreased cytochrome c release and caspase-3 activity. Aspirin initially caused a time-dependent decrease in COX-2 expression but subsequently, and unexpectedly, elevated the latter. Stimulation of COX-2 expression by aspirin was further enhanced following stimulation of the Wnt/beta-catenin pathway. Application of the COX-2 inhibitor NS-398 suppressed elevated COX-2 expression and promoted aspirin-induced apoptosis., Conclusion: These results demonstrate that the Wnt/beta-catenin pathway is a key modulator of aspirin-induced apoptosis in MSCs by regulation of mitochrondrial/caspase-3 function. More importantly, our findings suggest that aspirin may influence MSC survival under certain conditions; therefore, it should be used with caution when considering regenerative MSC transplantation in patients with concomitant chronic inflammatory diseases such as arthritis.

Background: Chronic exposure to high levels of free fatty acid (FFA) has adverse effects on the function of pancreatic beta-cell, with a consequent increase in the production of reactive oxygen species. Poly (ADP-Ribose) polymerase (PARP-1) overactivation leads to massive NAD(+) consumption and ATP depletion with induction of cellular necrosis under high reactive oxygen species. In the present study, we investigated whether inhibitors of poly(ADP-ribose) polymerase were capable of protecting beta-cells from death induced by extended exposure to FFA., Materials and Methods: RINm5F cell line was cultured in the presence of FFA (palmitate) in order to induce apoptosis, and then cells were treated with low-potency poly(ADP-ribose) polymerase inhibitor (3-aminobenzamide) or potent poly(ADP-ribose) polymerase inhibitor (PJ34). In order to explore whether poly(ADP-ribose) polymerase inhibitors could inhibit the apoptosis induced by FFA, expression of PARP-1 was measured by RT-qPCR and Western blot, while the apoptosis of RINm5F cells were analyzed by flow cytometry and Tdt-mediated dUTP Nick-End Labeling(TUNEL)., Results: Low-potency poly(ADP-ribose) polymerase inhibitor (3-aminobenzamide) significantly suppressed the impaired insulin secretion and FFA-induced apoptosis (P<0.01). However, potent poly(ADP-ribose) polymerase inhibitor (PJ34) had no significant effects on FFA-induced apoptosis (P>0.05). Moreover, low-potency inhibitors of PARP-1 increased PDX-1 expression down-regulated by FFA-treatment., Conclusions: These findings suggested that low-potency inhibitors of poly(ADP-ribose) polymerases could protect rat RINm5F cell line against free fatty acid-induced apoptosis, and it was through regulatory pathway of regulating PDX-1 expression.

Podocyte injury and loss contribute to progressive glomerulosclerosis. Peroxisome proliferator-activated receptor-gamma (PPAR-gamma) is a nuclear hormone receptor, which we have found to be increased in podocytes in a variety of kidney diseases. It is not known if PPAR-gamma contributes to renal injury or if it serves as a countermeasure to limit renal injury during disease progression. We tested these possibilities utilizing the puromycin aminonucleoside (PAN) model of renal injury in immortalized mouse podocytes. The cultured podocytes expressed PPAR-gamma mRNA at baseline but this was decreased by PAN. Pioglitazone, a pharmacologic agonist of PPAR-gamma, increased both PPAR-gamma mRNA and activity in injured podocytes, as assessed by a reporter plasmid assay. Further, pioglitazone significantly decreased PAN-induced podocyte apoptosis and necrosis while restoring podocyte differentiation. The PPAR-gamma agonist significantly restored expression of the cyclin-dependent kinase inhibitor p27 and the antiapoptotic molecule Bcl-xL while significantly decreasing proapoptotic caspase-3 activity. Pioglitazone tended to decrease PAN-induced transforming growth factor-beta (TGF-beta) mRNA expression. Our study shows that PPAR-gamma is normally expressed by podocytes and its activation is protective against PAN-induced apoptosis and necrosis. We postulate that this protective effect may be mediated in part by effects on p27 and TGF-beta expression.

We previously reported that oxidative stress and renal tubular damage occur in chronic hyperoxaluric rats. However, the in vivo responses of renal epithelial cells after vitamin E administration and their correlations with calcium oxalate (CaOx) crystal formation have not been evaluated. Male Wistar rats received 0.75% ethylene glycol (EG) for 7, 21, or 42 days to induce CaOx deposition (EG group). Another group of EG-treated rats received 200 mg kg(-1) of vitamin E intraperitoneally (EG+E group) to evaluate its effect on hyperoxaluria. Urinary electrolytes and biochemistry and levels of lipid peroxides and enzymes were examined, together with serum vitamin E levels. Levels of the tubular markers, alpha and mu glutathione S-transferase, proliferating cell nuclear antigen (PCNA), osteopontinin (OPN), and Tamm-Horsfall protein (THP) were also measured, and TUNEL staining was performed to examine the viability of the tubular epithelium. There were no significant differences between the two age-matched controls either untreated or given vitamin E. Compared to untreated controls, tubular cell death was increased at all time points in EG rats with a gradual increase in CaOx crystals, whereas the number of PCNA-positive cells was only significantly increased on day 21. In EG+E rats, tubular cell death was decreased compared to the EG group, and cell proliferation was seen at all time points, while CaOx crystal deposition was decreased, but hyperoxaluria, urinary lipid peroxides, and enzymuria were unaffected. Vitamin E supplement prevented the loss of OPN and THP in renal tissues by EG and the reduction in their levels in the urine. The beneficial effect of vitamin E in reducing CaOx accumulation is due to attenuation of tubular cell death and enhancement of the defensive roles of OPN and THP.

The aim of present study is to explore the cytoprotection of curcumin against 1-methyl-4-phenylpridinium ions (MPP(+))-induced apoptosis and the molecular mechanisms underlying in PC12 cells. Our findings indicated that MPP(+) significantly reduced the cell viability and induced apoptosis of PC12 cells. Curcumin protected PC12 cells against MPP(+)-induced cytotoxicity and apoptosis not only by inducing overexpression of Bcl-2, but also reducing the loss of mitochondrial membrane potential (MMP), an increase in intracellular reactive oxygen species (ROS) and overexpression of inducible nitric oxide synthase (iNOS). The selective iNOS inhibitor AG partly blocked MPP(+)-induced apoptosis of PC12 cells. The results of present study suggested that the cytoprotective effects of curcumin might be mediated, at least in part, by the Bcl-2-mitochondria-ROS-iNOS pathway. Because of its non-toxic property, curcumin could be further developed to treat the neurodegenerative diseases which are associated with oxidative stress, such as Parkinson's disease (PD).

Motexafin gadolinium (MGd, Xcytrin) is a tumor-localizing redox mediator that catalyzes the oxidation of intracellular reducing molecules including NADPH, ascorbate, protein and non-protein thiols, generating reactive oxygen species (ROS). MGd localizes to tumors and cooperates with radiation and chemotherapy to kill tumor cells in tissue culture and animal models. In this report, we demonstrate that MGd triggers the mitochondrial apoptotic pathway in the HF-1 lymphoma cell line as determined by loss of mitochondrial membrane potential, release of cytochrome c from mitochondria, activation of caspase-9 prior to caspase-8, cleavage of PARP and annexin V binding. There was minimal effect on MGd-induced apoptosis by the caspase inhibitor z-VAD-fmk, even though caspase-3 activity (as measured by DEVD-cleavage) was completely inhibited. However, MGd-induced apoptosis was reduced to baseline levels by the more potent caspase inhibitor Q-VD-OPh, demonstrating that MGd-induced apoptosis is indeed caspase-dependent. Apoptosis induced by dexamethasone, doxorubicin and etoposide (mediated through the mitochondrial pathway) was also more sensitive to inhibition by Q-VD-OPh than z-VAD-fmk. Our results demonstrating differential sensitivity of drug-induced apoptosis to caspase inhibitors suggest that the term "caspase-independent apoptosis" cannot be solely defined as apoptosis that is not inhibited by z-VAD-fmk as has been utilized in some published studies.

The human immunodeficiency virus type-1 (HIV-1) accessory gene vpr encodes a conserved 96-amino-acid protein that is necessary and sufficient for the HIV-1-induced block of cellular proliferation. Expression of vpr in CD4+ lymphocytes results in G2 arrest, followed by apoptosis. In a previous study, we identified the ataxia telangiectasia-mutated (ATM) and Rad3-related protein (ATR) as a cellular factor that mediates Vpr-induced cell cycle arrest. In the present study, we report that the breast cancer-associated protein-1 (BRCA1), a known target of ATR, is activated in the presence of Vpr. In addition, the gene encoding the growth arrest and DNA damage-45 protein alpha (GADD45alpha), a known transcriptional target of BRCA1, is upregulated by Vpr in an ATR-dependent manner. We demonstrate that RNAi-mediated silencing of either ATR or GADD45alpha leads to nearly complete suppression of the proapoptotic effect of Vpr. Our results support a model in which Vpr-induced apoptosis is mediated via ATR phosphorylation of BRCA1, and consequent upregulation of GADD45alpha.

Cell death through apoptosis plays a critical role in regulating cellular homeostasis. Whether the disposal of apoptotic cells through phagocytosis can actively induce immune tolerance in vivo, however, remains controversial. Here, we report in a rat model that without using immunosuppressants, transfusion of apoptotic splenocytes from the donor strain prior to transplant dramatically prolonged survival of heart allografts. Histological analysis verified that rejection signs were significantly ameliorated. Splenocytes from rats transfused with donor apoptotic cells showed a dramatically decreased response to donor lymphocyte stimulation. Most importantly, blockade of phagocytosis in vivo, either with gadolinium chloride to disrupt phagocyte function or with annexin V to block binding of exposed phosphotidylserine to its receptor on phagocytes, abolished the beneficial effect of transfused apoptotic cells on heart allograft survival. Our results demonstrate that donor apoptotic cells promote specific allograft acceptance and that phagocytosis of apoptotic cells in vivo plays a crucial role in maintaining immune tolerance.

Although colon carcinoma cells express Fas receptors, they are resistant to Fas-mediated apoptosis. Defects within the intracellular Fas signal transduction may be responsible. We investigated whether the Fas-associated phosphatase-1 (FAP-1), an inhibitor of Fas signal transduction, contributed to this resistance in colon carcinomas. In vivo, apoptosis of cancer cells was detected in situ using terminal deoxynucleotidyltransferase-mediated dUTP nick-end labelling (TUNEL). FAP-1, FasR, and Fas ligand (FasL) were detected using immunohistochemistry. In vitro, colon carcinoma cells were primarily cultured, and their sensitivity to Fas-mediated apoptosis was evaluated by treatment with agonistic anti-FasR CH11 IgM monoclonal antibody in the presence or absence of synthetic Ac-SLV (serine-leucine-valine) tripeptide. Fas-associated phosphatase-1 expression was detected in 20 out of 28 colon adenocarcinomas. In vivo, a positive correlation between the percentage of apoptotic tumour cells and the number of FasL-positive tumour infiltrating lymphocytes was observed in FAP-1 negative cancers, but not in FAP-1-positive ones. Primarily cultured colon cancer cells, which were refractory to CH-11-induced apoptosis, had higher expression of FAP-1 on protein and mRNA levels than the sensitive group. Resistance to Fas-mediated apoptosis in tumour cells could be abolished by Ac-SLV tripetides. Fas-associated phosphatase-1 expression protects colon cancer cells from Fas-mediated apoptosis, and blockade of FAP-1 and FasR interaction sensitises tumour cells to Fas-dependent apoptosis.

Light exposure can exacerbate the condition of a variety of human retinal diseases by increasing the rate of photoreceptor cell death. How light negatively affects photoreceptor cell survival is not yet fully understood. Previous studies involving light damage models have revealed two independent apoptotic pathways: low levels of light induce retinal degeneration in the arrestin -/- mouse via constitutive activation of the phototransduction cascade, whereas strong light exposure to the retina, such as in an albino eye, elicits photoreceptor cell death via activator protein (AP-1) induction. In order to better understand the initial gene expression changes underlying light damage, dark-reared arrestin -/- and albino BALB/c mice were exposed to constant white light (2000 lux), and their retinal morphology was assessed as a function of time. The expression profiles of retinal transcripts were then compared between dark-adapted and light-exposed arrestin -/-, pigmented wild-type and BALB/c mice at a time point when morphological changes were minimal. As expected, the dark-adapted samples showed little difference in expression pattern between the three genotypes. Among the genes differentially regulated by light in BALB/c, but not arrestin -/- retinas, were c-fos and other stress-induced early response genes. In both mouse models, a marked increase in expression of the bZIP family of transcription factors was observed. Our results show a select group of unique and overlapping sets of genes induced by light in the two mouse models. These expression changes may constitute the underlying initiating events leading to the two distinct mechanisms of light damage.

Survivin (SVV) is a new member of IAP-family (inhibitor of apoptosis, IAP) proteins. It can inhibit apoptosis induced by a variety of factors, and plays important roles during mitosis and cytokinesis of cells. Studies indicated that it is a tumor-specific anti-apoptosis factor. Survivin is expressed during embryonal development but lacks expression in terminally differentiated adult tissues. Interestingly, it becomes reexpressed in transformed cell lines and in a variety of human tumors. Its overexpression is prognostic of tumors and is implicated in the resistance to chemotherapy of tumor cells. SVV may be a new and widely applicable target for gene- and protein-based therapy of tumors.

Expression of membrane-bound Fas ligand (mFasL) on colon cancer cells serves as a potential mechanism to inhibit host immune function by inducing apoptosis of host lymphocytes. Membrane-bound FasL can be cleaved and released as a soluble mediator (sFasL), which may spread the apoptosis induction effect. Our study examined whether colon adenocarcinoma cells release sFasL, and induce apoptosis of host lymphocytes without direct cell-cell contact. In 12 consecutive patients with colon adenocarcinoma mFasL was identified in the tumours, sFasL was measured in the sera and apoptosis identified in tumour-infiltrating and peripheral blood lymphocytes. To analyse the function of sFasL, colon cancer cells were primarily cultured; sFasL was isolated from supernatants, measured, incubated with Fas-bearing Jurkat cells, and the resulting apoptosis was analysed. Serum levels of sFasL were significantly elevated in all colon cancer patients with mFasL expression in tumour tissues (n = 8). In these patients, the number of apoptotic lymphocytes was significantly increased within tumour and peripheral blood. Furthermore, sFasL was present in the corresponding supernatants and induced apoptosis of Jurkat cells in a dose-dependent manner. These findings suggest that mFasL-positive colon cancer cells release sFasL, and thus may induce apoptosis of host lymphocytes as a potential mechanism for immune evasion., (Copyright 2001 Cancer Research Campaign)

Background: Donor hepatocyte apoptosis that is induced by host cytotoxic T lymphocytes (CTLs) limits the application of hepatocyte transplantation. Hepatocytes from Bcl-2 transgenic mice can resist the lethal effect of anti-Fas antibody. However, the anti-apoptotic effect of Bcl-2 expression on allogeneic transplanted hepatocytes remains elusive. This study tested the feasibility of Bcl-2 gene transfer as an approach to inhibit CTL-mediated apoptosis in allogeneic transplanted hepatocytes., Methods: An adenovirus vector that encoded human Bcl-2 gene (AdCMVhBcl-2) was used to transfect cultured rat hepatocytes, which were then transplanted into allogeneic spleens. DNA fragmentation and caspase-3 activation were examined by terminal deoxynucleotidyl transferase-mediated deoxyuridine triphosphate nick end-labeling assay and immunohistochemistry for active caspase-3, respectively. Cocultivation of hepatocytes and allogeneic CD8(+) T lymphocytes was performed, and cytotoxicity on hepatocytes was examined by alanine transaminase release., Results: Bcl-2 gene transfer inhibited apoptosis and increased liver-associated enzyme activities in allogeneic transplanted hepatocytes, which were associated with inhibition of caspase-3 activation. Alanine transaminase release in hBcl-2 modified hepatocytes was lower compared with controls, which could not be further decreased by inhibition of Fas ligand and granzyme B., Conclusions: Adenovirus-mediated Bcl-2 gene transfer blocks CTL-mediated apoptosis in allogeneic hepatocytes by inhibition of caspase-3 activation. Bcl-2 gene transfer could be used to promote survival of transplanted hepatocytes.