HeLa Apoptosis Research Articles

Propofol promotes cell apoptosis via inhibiting HOTAIR mediated mTOR pathway in cervical cancer

ObjectivesCervical cancer is one of the most common gynecologic malignant tumors. Propofol has been proposed to play a role of antitumor in various cancers. However, the functions and mechanisms of Propofol in cervical cancer is still not clear. MethodsIn vitro, the different concentrations of propofol were co-incubated with cervical cancer cell lines, including Hela, Caski and C-33A cells respectively. The pcDNA-HOTAIR plasmid was transfected into cells after the treatment of 10 μg/ml propofol. The cell viability and apoptosis were detected by MTT assay and TUNEL method. In vivo, propofol was injected into mice of transplantation tumor with Caski cells or with pcDNA-HOTAIR treated Caski cells. ResultsPropofol significantly decreased the cell viability and increased the cell apoptosis in Hela, Caski and C-33A cells, while HOTAIR overexpression promoted cell viability and inhibits cell apoptosis. mTOR/p70S6K protein expression levels were also markedly reduced by propofol but the effects were reversed with pcDNA-HOTAIR. In vivo, propofol inhibited the tumor size but had no inhibition effect in HOTAIR overexpression group. ConclusionPropofol inhibited tumor size, cell viability and promoted cell apoptosis via inhibiting mTOR/p70S6K pathway mediated by HOTAIR in cervical cancer.

The effect of bovine rotavirus and its nonstructural protein 4 on ER stress-mediated apoptosis in HeLa and HT-29 cells.

Endoplasmic reticulum (ER) plays important roles in multiple cellular processes as well as cell survival and apoptosis. Perturbation of ER functions leads to ER stress and unfolded protein response (UPR). The primary goal of this response is cell survival, but severe ER stress can trigger apoptosis signaling. In tumor cells, chronically activated UPR response provides tumor growth. So, apoptosis induced by the ER stress has been the target for anti-cancer therapy. In this in vitro study, we examined the apoptotic effect associated with ER stress of bovine rotavirus and its nonstructural protein 4 (NSP4) alone in two cancer cell lines. The plasmid pcDNA3.1 encoding NSP4 protein of bovine rotavirus transfected with lipofectamine 2000 into the HeLa and HT-29 cells for protein production. MTT, flow cytometry, and Western blot were used to evaluate the cell viability, apoptosis, and expression level of C/EBP-homologous protein (CHOP) and activated caspase-4. In parallel, the apoptotic effect of the bovine rotavirus associated with ER stress in the infected cells was examined too. The cytotoxic and apoptotic effect of NSP4 protein on the cells were statistically significant compared to the control groups. However, Western blot showed that the expression of the NSP4 protein by recombinant plasmid did not lead to high expression of CHOP and activation of caspase-4. Interestingly, rotavirus not only induced significant apoptosis but also caused an increase in CHOP expression and caspase-4 activation in the infected cells compared to control. As a result, NSP4 protein and bovine rotavirus can be considered a potential novel bio-therapeutic strategy for cancer treatment.

Structurally related ganoderic acids induce apoptosis in human cervical cancer HeLa cells: Involvement of oxidative stress and antioxidant protective system

Ganoderic acids (GAs) produced by Ganoderma lucidum possess anticancer activities with the generation of reactive oxygen species (ROS). However, the role of oxidative stress in apoptotic process induced by GAs is still undefined. In this study, the effects of four structurally related GAs, i.e. GA-T, GA-Mk, and two deacetylated derivatives of GA-T (GA-T1 and GA-T2) on the antioxidant defense system and induced apoptosis in cervical cancer cells HeLa were investigated in vitro. Our results indicated that the tested GAs (5–40 μM) induced apoptotic cell death through mitochondrial membrane potential decrease and activation of caspase-9 and caspase-3. Furthermore, GAs increased the generation of intracellular ROS and attenuated antioxidant defense system by decreasing glutathione (GSH) level, superoxide dismutase (SOD) and glutathione peroxidase (GPX) activities. The above effects were remarkably blocked by the exogenous antioxidants, i.e. N-acetylcysteine, catalase and diphenyleneiodonium chloride. The potency of the four GAs toward induced apoptosis, generation of ROS and suppression of antioxidant defense system was in the order of: GA-T > GA-Mk ≈ GA-T1 > GA-T2 in HeLa cells. These findings suggest that GAs induced mitochondria-dependent cell apoptosis in HeLa cells are mediated via enhancing oxidative stress and depressing antioxidant defense. Additionally, the acetylation of hydroxyl groups in GAs may contribute to their pro-oxidant activities and cytotoxicity, which is helpful to the development of novel chemotherapy agents.

MALAT1-miR-124-RBG2 axis is involved in growth and invasion of HR-HPV-positive cervical cancer cells.

Metastasis-associated lung adenocarcinoma transcript 1 (MALAT 1) is a large, infrequently spliced non-coding RNA aberrantly expressed in cervical cancer. But the molecular mechanisms of its oncogenic role are still not quite clear. The present study explored whether there is a competing endogenous RNAs (ceRNAs) mechanism involved in the oncogenic effect of MALAT1. MALAT1 expression was firstly verified in high-risk human papillomavirus (HR-HPV)-positive tumor tissues and cell lines. Its regulation over miR-124 and the downstream target of miR-124 in regulation of growth, invasion, and apoptosis of the cancer cells are also studied. Findings of this study confirmed higher MALAT1 expression in HR-HPV (+) cervical cancer. Knockdown of endogenous MALAT1 significantly reduced cell growth rate and invasion and increased cell apoptosis of Hela and siHa cells. Besides, knockdown of MALAT1 increased the expression of miRNA-124, while ectopic expression of miR-124 decreased MALAT1 expression. In addition, we also verified a direct interaction between miR-124 and 3'UTR of GRB2. MALAT1 can indirectly modulate GRB2 expression via competing miR-124. Knockdown of GRB2 reduced cell invasion and increased cell apoptosis. In conclusion, MALAT1 can promote HR-HPV (+) cancer cell growth and invasion at least partially through the MALAT1-miR-124-RBG2 axis. This finding might provide some useful evidence about the lncRNA interaction regulatory network in tumorigenesis cervical cancer.

Combined ultrasound-curcumin treatment of human cervical cancer cells

ObjectivesHuman papillomavirus (HPV) is associated with cervical cancer. Studies showed curcumin inhibits HPV oncogenes expression but curcumin has low bioavailability. The objectives were: (1) to study ultrasound enhancement of curcumin effects on HeLa, SiHa and C33A, (2) to compare two frequencies for sonoporation and (3) to detect cell-free DNA released by the treatment. Study designHeLa, SiHa and C33A cells (non-HPV control) were processed and exposed to either: (1) 10μM curcumin only, (2) 10μM curcumin with 8s of 7.5MHz ultrasound, (3) 10μM curcumin with 8s of 5.0MHz ultrasound, (4) control medium, or (5) 8s of 7.5MHz ultrasound. The five treated groups were incubated (48h) and analyzed by dual fluorescence apoptosis/necrosis assay. DNA in spent media was analyzed by capillary analysis. ResultsCombined curcumin ultrasound resulted in 9-, 12- and 16-fold higher necrosis in HeLa, SiHa and C33A cells respectively. Increased necrosis correlated with higher ultrasound frequencies. There was increased apoptosis in HeLa or SiHa cells with the combined treatment. Curcumin alone resulted in a lesser 2–4-fold increase in necrosis in the groups. Cell-free DNA was detected in the spent media of HeLa and SiHa but not C33A cultures. ConclusionsThe results showed enhanced necrosis in cervical carcinoma cell lines after combined treatment and confirmed the ultrasound capacity to increase effectiveness of curcumin. Cancer cells were smaller post-treatment suggesting microtubule structural disruption. Cell-free DNA was low molecular weight consistent with lysed host cell.

Regulation of p53 expression and apoptosis by vault RNA2-1-5p in cervical cancer cells.

nc886 or VRNA2-1 has recently been identified as a noncoding RNA instead of a vault RNA or a pre-microRNA. Several studies have reported that pre-miR-886 plays a tumor-suppressive role in a wide range of cancer cells through its activity as a cellular protein kinase RNA-activated (PKR) ligand and repressor. However, by sequencing stem-PCR products, we found that a microRNA originating from this precursor, vault RNA2-1-5p (VTRNA2-1-5p), occurs in cervical cancer cells. The expression levels of the predicted targets of VTRNA2-1-5p are negatively correlated with VTRNA2-1-5p levels by quantitative reversion transcription PCR (qRT-PCR). Previous results have shown that VTRNA2-1-5p is overexpressed in human cervical squamous cell carcinomas (CSCCs) compared with adjacent healthy tissues. Inhibition of VTRNA2-1-5p increases Bax protein expression and apoptotic cell death in cervical cancer cells. Our findings suggest that VTRNA2-1-5p has oncogenic activity related to the progression of cervical cancer. Here, we report that VTRNA2-1-5p directly targeted p53 expression and functioned as an oncomir in cervical cancer. VTRNA2-1-5p inhibition decreased cervical cancer cell invasion, proliferation, and tumorigenicity while increasing apoptosis and p53 expression. Interestingly, VTRNA2-1-5p inhibition also increased cisplatin-induced apoptosis of HeLa and SiHa cells. In human clinical cervical cancer specimens, low p53 expression and high VTRNA2-1-5p expression were positively associated.In addition, VTRNA2-1-5p was found to directly target the 5' and 3' untranslated regions (UTRs) of p53. We propose that VTRNA2-1-5p is a direct regulator of p53 and suggest that it plays an essential role in the apoptosis and proliferation of cervical cancer cells.

Activating PTEN by COX-2 inhibitors antagonizes radiation-induced AKT activation contributing to radiosensitization

Radiotherapy is still one of the most effective nonsurgical treatments for many tumors. However, radioresistance remains a major impediment to radiotherapy. Although COX-2 inhibitors can induce radiosensitization, the underlying mechanism is not fully understood. In this study, we showed that COX-2 selective inhibitor celecoxib enhanced the radiation-induced inhibition of cell proliferation and apoptosis in HeLa and SACC-83 cells. Treatment with celecoxib alone dephosphorylated phosphatase and tensin homolog deleted on chromosome ten (PTEN), promoted PTEN membrane translocation or activation, and correspondingly dephosphorylated or inactivated protein kinase B (AKT). By contrast, treatment with radiation alone increased PTEN phosphorylation, inhibited PTEN membrane translocation and correspondingly activated AKT in the two cell lines. However, treatment with celecoxib or another COX-2 selective inhibitor (valdecoxib) completely blocked radiation-induced increase of PTEN phosphorylation, rescued radiation-induced decrease in PTEN membrane translocation, and correspondingly inactivated AKT. Moreover, celecoxib could also upregulate PTEN protein expression by downregulating Sp1 expression, thereby leading to the activation of PTEN transcription. Our results suggested that COX-2 inhibitors could enhance radiosensitization at least partially by activating PTEN to antagonize radiation-induced AKT activation.

Carbon ion beam triggers both caspase-dependent and caspase-independent pathway of apoptosis in HeLa and status of PARP-1 controls intensity of apoptosis.

High linear energy transfer (LET) carbon ion beam (CIB) is becoming very promising tool for various cancer treatments and is more efficient than conventional low LET gamma or X-rays to kill malignant or radio-resistant cells, although detailed mechanism of cell death is still unknown. Poly (ADP-ribose) polymerase-1 (PARP-1) is a key player in DNA repair and its inhibitors are well-known as radio-sensitizer for low LET radiation. The objective of our study was to find mechanism(s) of induction of apoptosis by CIB and role of PARP-1 in CIB-induced apoptosis. We observed overall higher apoptosis in PARP-1 knocked down HeLa cells (HsiI) compared with negative control H-vector cells after irradiation with CIB (0-4Gy). CIB activated both intrinsic and extrinsic pathways of apoptosis via caspase-9 and caspase-8 activation respectively, followed by caspase-3 activation, apoptotic body, nucleosomal ladder formation and sub-G1 accumulation. Apoptosis inducing factor translocation into nucleus in H-vector but not in HsiI cells after CIB irradiation contributed caspase-independent apoptosis. Higher p53 expression was observed in HsiI cells compared with H-vector after exposure with CIB. Notably, we observed about 37% fall of mitochondrial membrane potential, activation of caspase-9 and caspase-3 and mild activation of caspase-8 without any detectable apoptotic body formation in un-irradiated HsiI cells. We conclude that reduction of PARP-1 expression activates apoptotic signals via intrinsic and extrinsic pathways in un-irradiated cells. CIB irradiation further intensified both intrinsic and extrinsic pathways of apoptosis synergistically along with up-regulation of p53 in HsiI cells resulting overall higher apoptosis in HsiI than H-vector.

3-(3-Hydroxy-4-methoxyphenyl)-4-(3,4,5-trimethoxyphenyl)-1,2,5-selenadiazole (G-1103), a novel combretastatin A-4 analog, induces G2/M arrest and apoptosis by disrupting tubulin polymerization in human cervical HeLa cells and fibrosarcoma HT-1080 cells

Microtubule is a popular target for anticancer drugs. In this study, we describe the effect 3-(3-hydroxy-4-methoxyphenyl)-4-(3,4,5-trimethoxyphenyl)-1,2,5-selenadiazole (G-1103), a newly synthesized analog of combretastatin A-4 (CA-4), showing a strong time- and dose-dependent anti-proliferative effect on human cervical cancer HeLa cells and human fibrosarcoma HT-1080 cells. We demonstrated that the growth inhibitory effects of G-1103 in HeLa and HT-1080 cells were associated with microtubule depolymerization and proved that G-1103 acted as microtubule destabilizing agent. Furthermore, cell cycle analysis revealed that G-1103 treatment resulted in cell cycle arrest at the G2/M phase in a time-dependent manner with subsequent apoptosis induction. Western blot analysis revealed that down-regulation of cdc25c and up-regulation of cyclin B1 was related with G2/M arrest in HeLa and HT-1080 cells treatment with G-1103. In addition, G-1103 induced HeLa cell apoptosis by up-regulating cleaved caspase-3, Fas, cleaved caspase-8 expression, which indicated that G-1103 induced HeLa cell apoptosis was mainly associated with death receptor pathway. However, G-1103 induced HT-1080 cell apoptosis by up-regulating cleaved caspase-3, Fas, cleaved caspase-8, Bax and cleaved caspase-9 expression and down-regulating anti-apoptotic protein Bcl-2 expression, which indicated that G-1103 induced HT-1080 cell apoptosis was associated with both mitochondrial and death receptor pathway. Taken together, all the data demonstrated that G-1103 exhibited its antitumor activity through disrupting the microtubule assembly, causing cell cycle arrest and consequently inducing apoptosis in HeLa and HT-1080 cells. Therefore, the novel compound G-1103 is a promising microtubule inhibitor that has great potentials for therapeutic treatment of various malignancies.

Ginsenoside‑Rg5 induces apoptosis and DNA damage in human cervical cancer cells.

Panax ginseng is traditionally used as a remedy for cancer, inflammation, stress and aging, and ginsenoside-Rg5 is a major bioactive constituent of steamed ginseng. The present study aimed to evaluate whether ginsenoside-Rg5 had any marked cytotoxic, apoptotic or DNA-damaging effects in human cervical cancer cells. Five human cervical cancer cell lines (HeLa, MS751, C33A, Me180 and HT-3) were used to investigate the cytotoxicity of ginsenoside-Rg5 using a 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay. Additionally, the effects of ginsenoside-Rg5 on the apoptosis of HeLa and MS751 cells were detected using DNA ladder assays and flow cytometry. DNA damage was assessed in the HeLa and MS751 cells using alkaline comet assays and by detection of γH2AX focus formation. The HeLa and MS751 cells were significantly more sensitive to ginsenoside-Rg5 treatment compared with the C-33A, HT-3 and Me180 cells. As expected, ginsenoside-Rg5 induced significant concentration- and time-dependent increases in apoptosis. In addition, ginsenoside-Rg5 induced significant concentration-dependent increases in the level of DNA damage compared with the negative control. Consistent with the comet assay data, the percentage of γH2AX-positive HeLa and MS751 cells also revealed that ginsenoside-Rg5 caused DNA double-strands to break in a concentration-dependent manner. In conclusion, ginsenoside-Rg5 had marked genotoxic effects in the HeLa and MS751 cells and, thus, demonstrates potential as a genotoxic or cytotoxic drug for the treatment of cervical cancer.

Synthesis and anticervical cancer activity of novel pH responsive micelles for oral curcumin delivery

Curcumin (CM) has demonstrated safety and efficacy as a drug, but its pharmaceutical role is restricted as a result of extremely low aqueous solubility, rapid systemic elimination, inadequate tissue absorption and degradation at alkaline pH; properties that severely curtail its bioavailability. To address this issue, CM was encapsulated within pH responsive amphiphilic chitosan, resulting in the formation of 100nm spontaneously self-assembled polymeric micelles in water. The amphiphilic chitosan, namely N-benzyl-N,O-succinyl chitosan (BSCS), was prepared by reductive N-benzylation and N,O-succinylation. The stability of micelles after being re-dispersed in water was investigated using glycine as a cryoprotectant, and the average sizes were shown to be maintained at a level lower than 200nm for up to 4 months, at temperatures of 4°C and 25°C. In vitro drug release results showed that CM was slowly released from the micelles without any burst effect in the intestine (pH 5.5–7.4), with limited release in the stomach (pH 1.2). Cytotoxicity assays indicated that CM loaded micelles showed half maximal inhibitory concentrations (IC50) 4.7-, 3.6-, and 12.2-fold lower than that of free CM in HeLa, SiHa and C33a cervical cell lines, respectively. Cellular uptake of micelles was confirmed by confocal laser scanning microscopy and flow cytometry, with a 6-fold significant increase in the amount of CM loaded micelles compared to free CM in all cervical cancer cells. Notably, CM loaded micelles promoted an increase (30–55%) in the percentage of early apoptosis of HeLa, SiHa and C33a cells, compared to free CM. These results suggest that BSCS micelles may be a promising carrier for effective oral delivery of CM.

Synthesis of a platinum(II) complex with 2-(4-methoxy-phenyl) imidazo [4,5-f]-[1,10] phenanthrolin and study of its antitumor activity.

A new platinum(II) complex of [Pt(II)(L) (pn)]Cl·2H2O (1) (pn=1,3-propanediamine) with 2-(4-methoxy-phenyl)imidazo [4,5-f]-[1,10]phenanthrolin (H-L) was synthesized and characterized. In complex 1, the platinum adopts a four-coordinated square planar geometry. Complex 1 exhibited selective cytotoxicity against NCI-H460, BEL-7402, SK-OV-3, SK-OV-3/DDP and HeLa cell lines with IC50 values in the micromolar range (9.7-35.8μM), but low cytotoxicity toward normal human liver HL-7702 cells. Complex 1 caused HeLa cell cycle arrest at S phase and it induced HeLa apoptosis by the activation of caspase-3/9. Various experiments showed that complex 1 preferred to bind with G-quadruplex in c-myc. Taken together, we found that complex 1 exerted its antitumor activity mainly via inhibiting telomerase by interaction with c-myc quadruplex and activation of caspase-3/9.

RASSF1A suppresses proliferation of cervical cancer cells.

This study aimed to explore the effects of ras association domain family 1 A (RASSF1A) on proliferation and apoptosis of human cervical cancer cell line Hela cells. RASSF1A was cloned into the pcDNA3.1(+) vector to generate pcDNA3.1(+)-RASSF1A plasmid for transfection into Hela cells. Changes in the proliferation and apoptosis of cultured Hela cells were examined by the 3-(4,5-dimethyl-thiazol-2-yl)-2,5-diphenyltetrazolium chloride assay and flow cytometry. A protein array was used to analyze the expression of apoptotic factors. Plasmid pcDNA3.1(+)-RASSF1A was generated and transfected into Hela cells to stably express RASSF1A in Hela cells. RASSF1A transfection was effective in inhibiting the proliferation of Hela cells up to 52.4%, as compared to cells transfected with an empty plasmid. RASSF1A expression also successfully induced apoptosis in human cervical cells with an apoptosis rate of 20.5%. More importantly, protein array results showed that RASSF1 A transfection induced overexpression of p21 and caspase 8, while decreasing the expression of survivin in Hela cells. RASSF1A expression was effective in suppressing the proliferation and increasing apoptosis of Hela cells, and may be a potential therapy for cervical cancer in clinic.

Synthesis, characterization and cytotoxic activity studies of two ruthenium(II) complexes

Two Ru(II) polypyridyl complexes [Ru(phen)2(idpq)](ClO4)2 (1) and [Ru(dmp)2(idpq)](ClO4)2 (2) were synthesized and characterized. Cytotoxicity, apoptosis, cell cycle arrest, reactive oxygen species and mitochondrial membrane potential were assayed. The IC50 values of complexes 1 and 2 toward HepG-2, A549, MG-63 and HeLa cell lines range from 15.1±2.1 to 24.8±2.4μM. The complexes can effectively induce apoptosis and induce cell cycle arrest at G0/G1 phase by an increase of 4.88% for 1 and 6.64% for 2 at G0/G1 phase in HeLa cells. Complexes 1 and 2 can enter the cytoplasm and accumulate in the nuclei. The complexes can enhance the level of reactive oxygen species. The ratio of the red/green is 0.74 and 0.52 for complexes 1 and 2, which suggests that the complexes induce a decrease of mitochondrial membrane potential. These complexes induce apoptosis in HeLa through ROS-mediated mitochondrial dysfunction pathway.

Conditioned Media of Human Umbilical Cord Blood Mesenchymal Stem Cell-derived Secretome Induced Apoptosis and Inhibited Growth of HeLa Cells

BACKGROUND: Secreted factors contained in conditioned media (CM) of human umbilical cord blood mesenchymal stem cells (hUCB-MSCs) known as secretome, was suspected to have important roles in regulating cells. This study was conducted to investigate the role of CM-hUCB-MSCs-derived secretome in apoptosis and growth of HeLa cells.METHODS: HeLa cells were treated with secretome in various concentrations (0, 0.2, 2 and 20%) for 24 and 48 hours. Trypan blue exclusion assay was performed to detect cell viability. Meanwhile sub-G1 apoptotic assay was performed to detect apoptotic cells. The transition of mitochondrial transmembrane potential (TMP), which occurs in the apoptotic process, was analyzed by mitochondrial membrane potential (ΔΨM) assay. Both sub-G1 and ΔΨM assays were performed using FACSCanto flow cytometer. Statistical analyses were conducted using IBM SPSS Statistics to detect significance level at p<0.05.RESULTS: Secretome significantly induced cell death starting at concentration of 0.2% within a 24-hour period (p<0.05). Secretome significantly induced cell death in concentration and time dependent manner (p<0.05). The cell death was then confirmed as apoptosis through sub-G1 analysis. Due to the underlying apoptotic mechanism, we found distinct decrease of TMP, indicating an increase in mitochondrial membrane permeability of HeLa cells. In addition, we found that HeLa cell growth was inhibited partially by secretome.CONCLUSION: Taken together, we conclude that CMhUCB-MSCs-derived secretome significantly induced apoptosis of HeLa cells in a concentration and time dependent manner through mitochondrial apoptotic pathway. The secretome might also play important role in inhibiting HeLa cell growth.KEYWORDS: umbilical cord blood, mesenchymal stem cell, secretome, apoptosis, growth, cancer

Nanoconjugation: A Materials Approach to Enhance Epidermal Growth Factor Induced Apoptosis.

Apoptosis evasion is a hallmark of cancer that motivates the development of novel strategies for inducing cell death in a controlled fashion. The size-compatibility of nanoparticles (NPs) with cellular components provides new opportunities for regulating cellular processes, potentially including apoptosis. We investigated the impact of the covalent attachment of epidermal growth factor (EGF) to 40 nm diameter Au NPs on cellular apoptosis levels, quantified as caspase-3 activity, in two in vitro cancer cell lines: A431 and HeLa. Our studies show that nanoconjugation enhances EGF-induced apoptosis in EGF receptor (EGFR) overexpressing A431 and triggers a quantifiable increase in apoptosis in HeLa. The latter has physiological receptor expression levels and does not show apoptosis in response to free EGF. Endocytosis and trafficking are involved in key EGFR regulation processes, most prominently signal termination. Our experimental findings indicate that these processes can be manipulated through nanoconjugation to induce apoptosis.

Non-transmissible Sendai virus vector encoding c-myc suppressor FBP-interacting repressor for cancer therapy.

To investigate a novel therapeutic strategy to target and suppress c-myc in human cancers using far up stream element (FUSE)-binding protein-interacting repressor (FIR). Endogenous c-Myc suppression and apoptosis induction by a transient FIR-expressing vector was examined in vivo via a HA-tagged FIR (HA-FIR) expression vector. A fusion gene-deficient, non-transmissible, Sendai virus (SeV) vector encoding FIR cDNA, SeV/dF/FIR, was prepared. SeV/dF/FIR was examined for its gene transduction efficiency, viral dose dependency of antitumor effect and apoptosis induction in HeLa (cervical squamous cell carcinoma) cells and SW480 (colon adenocarcinoma) cells. Antitumor efficacy in a mouse xenograft model was also examined. The molecular mechanism of the anti-tumor effect and c-Myc suppression by SeV/dF/FIR was examined using Spliceostatin A (SSA), a SAP155 inhibitor, or SAP155 siRNA which induce c-Myc by increasing FIR∆exon2 in HeLa cells. FIR was found to repress c-myc transcription and in turn the overexpression of FIR drove apoptosis through c-myc suppression. Thus, FIR expressing vectors are potentially applicable for cancer therapy. FIR is alternatively spliced by SAP155 in cancer cells lacking the transcriptional repression domain within exon 2 (FIR∆exon2), counteracting FIR for c-Myc protein expression. Furthermore, FIR forms a complex with SAP155 and inhibits mutual well-established functions. Thus, both the valuable effects and side effects of exogenous FIR stimuli should be tested for future clinical application. SeV/dF/FIR, a cytoplasmic RNA virus, was successfully prepared and showed highly efficient gene transduction in in vivo experiments. Furthermore, in nude mouse tumor xenograft models, SeV/dF/FIR displayed high antitumor efficiency against human cancer cells. SeV/dF/FIR suppressed SSA-activated c-Myc. SAP155 siRNA, potentially produces FIR∆exon2, and led to c-Myc overexpression with phosphorylation at Ser62. HA-FIR suppressed endogenous c-Myc expression and induced apoptosis in HeLa and SW480 cells. A c-myc transcriptional suppressor FIR expressing SeV/dF/FIR showed high gene transduction efficiency with significant antitumor effects and apoptosis induction in HeLa and SW480 cells. SeV/dF/FIR showed strong tumor growth suppression with no significant side effects in an animal xenograft model, thus SeV/dF/FIR is potentially applicable for future clinical cancer treatment.

Involvement of the Nrf2 Pathway in the Regulation of Pterostilbene-Induced Apoptosis in HeLa Cells via ER Stress

Among the various cancer cell lines, HeLa cells were found to be sensitive to pterostilbene (Pte), a compound that is enriched in small fruits such as grapes and berries. However, the mechanism involved in the cytotoxicity of Pte has not been fully characterized. Using biochemical and free radical biological experiments in vitro, we identified the pro-apoptotic profiles of Pte and evaluated the level of redox stress-triggered ER stress during HeLa cell apoptosis. The data showed a strong dose-response relationship between Pte exposure and the characteristics of HeLa apoptosis in terms of changes in apoptotic morphology, DNA fragmentation, and activated caspases in the intrinsic apoptotic pathway. During drug exposure, alterations in the intracellular redox homeostasis that favor oxidation were necessary to cause ER stress-related apoptosis, as demonstrated by enzymatic and non-enzymatic redox modulators. A statistically significant and dose-dependent increase (P < 0.05) was found with regard to the unique expression levels of Nrf2/ARE downstream target genes in HeLa cells undergoing late apoptosis, levels that were restored with anti-oxidant application with the Pte treatment. Our research demonstrated that Pte trigged ER stress by redox homeostasis imbalance, which was negatively regulated by a following activation of Nrf2.

Gliotoxin Isolated from Marine Fungus Aspergillus sp. Induces Apoptosis of Human Cervical Cancer and Chondrosarcoma Cells

Gliotoxin, a secondary metabolite produced by marine fungus Aspergillus sp., possesses various biological activities including anticancer activity. However, the mechanism underlying gliotoxin-induced cytotoxicity on human cervical cancer (Hela) and human chondrosarcoma (SW1353) cells remains unclear. In this study, we focused on the effect of gliotoxin induction on apoptosis, the activating expressions of caspase family enzymes in the cells. Apoptotic cell levels were measured through DAPI and Annexin V/Propidium Iodide (PI) double staining analysis. The apoptotic protein expression of Bcl-2 and caspase family was detected by Western blot in Hela and SW1353 cells. Our results showed that gliotoxin treatment inhibited cell proliferation and induced significant morphological changes. Gliotoxin induced apoptosis was further confirmed by DNA fragmentation, chromatin condensation and disrupted mitochondrial membrane potential. Gliotoxin-induced activation of caspase-3, caspase-8 and caspase-9, down-regulation of Bcl-2, up-regulation of Bax and cytochromec (cyt c) release showed evidence for the gliotoxin activity on apoptosis. These findings suggest that gliotoxin isolated from marine fungus Aspergillus sp. induced apoptosis in Hela and SW1353 cells via the mitochondrial pathway followed by downstream events leading to apoptotic mode of cell death.

A new synthetic Cu(II) compound, [Cu3(p-3-bmb)2Cl4·(CH3OH)2]n, inhibits tumor growth in vivo and in vitro

Copper(II) mixed-ligand complex, [Cu3(p-3-bmb)2Cl4 (CH3OH)2]n (Cu(II) compound), where p-3-bmb=1((2-(pyridine-3-yl)-1H-benzoimidazol-1-yl) methyl)-1Hbenzotriazole, has been recently found to possess potent anti-tumor activities both in vivo and in vitro. In this study, we demonstrated that Cu(II) compound significantly inhibited tumor growth in mice that inoculated with S180 cells. Meanwhile, the viabilities of HeLa and SGC-7901 cells were inhibited by Cu(II) compound with IC50 values in the range of 5–30μM. Further mechanistic studies revealed that Cu(II) compound treatment induced cell cycle arrested at G1 phase through p53, p21, cyclinD1, cdk4, pRb and E2F1. Cu(II) compound treatment also induced apoptosis of HeLa and SGC-7901 cells which were accompanied with decrease in mitochondrial membrane potential, increase in reactive oxygen species production, release of cytochrome C, cleavage of caspase-9, caspase-3 and poly ADP-ribose polymerase (PARP) as well as activations of bcl-2 and bax. These results indicate that Cu(II) compound has a promising potential to become a novel anti-cancer agent.