Oleandrin induces apoptosis via activating endoplasmic reticulum stress in breast cancer cells.

BACKGROUND: Breast cancer is the most common malignant tumor in women. Due to limited treatment outcome and high rate of metastasis, the prognosis is especially poor for triple-negative breast cancer. It is urgent to discover and develop novel agents for treatment of breast cancer. Herein, we investigated the potential mechanisms of Oleandrin's (a cardiac glycoside) cytotoxic activity against breast cancer cells. METHODS: Cell proliferation was assessed by xCELLigence Real-Time Cell Analyzer (RTCA)-MP system. Apoptotic cells were detected by using Annexin V/PI staining and nuclear fragments observation. The effect of oleandrin on ATP1B3 expression and markers of ER stress were determined by western blot. A primary cell sensitivity assay was performed via a collagen gel droplet-embedded culture drug sensitivity method (CD-DST). RESULTS: Oleandrin suppressed cell proliferation and colony formation in the three breast cancer cell lines but did not affect normal mammary epithelial cells. Additionally, the expression of ATP1B3 was higher in the three breast cancer cell lines compared to MCF10A cells. Treatment with oleandrin increased the number of apoptotic cells and led to nuclear pyknosis, fragmentation, and apoptotic body formation in breast cancer cells. Furthermore, oleandrin treatment increased expression of Bax and Bim but decreased that of Bcl-2. Treatment with oleandrin also upregulated the expression of endoplasmic reticulum stress associated proteins, including eIF2α, ATF4, and CHOP, but not PERK. oleandrin treatment also induced the phosphorylation of PERK and eIF2α. Of note, oleandrin exhibited antitumor effects on patient-derived breast cancer cells under three-dimensional culture conditions. CONCLUSIONS: Taken together, our results suggest that oleandrin induces mitochondrial-mediated apoptosis by activating endoplasmic reticulum stress in breast cancer. Moreover, oleandrin may be an effective strategy for the treatment of breast cancer.

Interference of lysine-specific demethylase 1 inhibits cellular invasion and proliferation in vivo in gastric cancer MKN-28 cells.

BACKGROUND: Lysine-specific demethylase 1(LSD1), the first identified histone demethylase, plays an important role in the epigenetic regulation of gene activation and repression. Up-regulated LSD1expression has been reported in several malignant tumors.Our aim, therefore, was to better understand the mechanisms underlying the upregulation of LSD1 in gastric cancer. METHODS: We used lentiviral shRNA to knockdown LSD1 in the gastric cancer MKN-28 cell line. Cell proliferation was measured by MTT assay while cell apoptosis was assessed by Annexin V-FITC/PI double staining flow cytometry. The invasive potential of gastric cancer cells was determined by matrigel invasion assay. Protein expression was detected by Western blot. In vivo, the effect of knocking down LSD1 on tumor growth and protein expression in gastric cancer cells in nude mice was investigated. RESULTS: LSD1 knockdown in MKN-28 cell lines resulted in increasing the activity of cisplatin in vitro and the inhibition of cancer cell proliferation and invasion, and induced cell apoptosis. The expression of TGF-ß1, VEGF, Bcl-2, ß-catenin, p-ERK and p-Smad 2/3 proteins was inhibited in LSD1 knockdown cells. Moreover, in an in vivo model of gastric cancer, LSD1 knockdown suppressed tumor growth and protein expression. CONCLUSION: LSD1 knockdown affected the fuction of gastric cancer MKN-28 cell line. LSD1 may be a latent target in the diagnosis and therapy of gastric cancer.

Antitumor effect of dendritic cells transfected with prostate-specific membrane antigen recombinant adenovirus on prostate cancer: An in vitro study.

The aim of the present study was to construct a dendritic cell (DC) vaccine transfected with a prostate-specific membrane antigen (PSMA) recombinant adenovirus and to observe the ability of the recombinant DCs in eliciting a PSMA-directed T­cell response to prostate cancer (PCa) in vitro. Replication­defective adenoviral vectors, were constructed using the Adxsi system. The virus titer was measured by TCID50 assay, and the expression of the PSMA gene was identified by polymerase chain reaction (PCR) generation of peripheral blood mononuclear cell (PBMC) derived DCs in vitro. In addition, a PE­7AAD apoptosis and necrosis kit was applied to detect the survival of DCs at different MOI values to determine the optimal MOI. Morphological changes of DC were observed under a fluorescence microscope, expression of the PSMA protein was detected by western blotting 48 h after transfection, the expression of DC markers prior to and following transfection was detected by direct immunofluorescence, and the interleukin (IL)-12 concentration in the culture supernatant of the three groups was measured by ELISA. The antitumor effect of DC-stimulated cytotoxic T lymphocytes (CTLs) on different PCa cell lines was analyzed using a Cell Counting Kit­8 assay. The optimal MOI value was determined to be 200. The PSMA protein was expressed in DCs, and the recombinant adenovirus did not impact the maturation and morphological changes of the DCs. The expression levels of the co-stimulatory molecules, CD80, CD83, CD86 and HLA­DR, were significantly higher in the Ad­PSMA­DC group than in the other two groups (P<0.05). The concentration of IL­12 in the supernatant of the Ad­PSMA­DC group (79.51±1.60 pg) was comparable with that of the Ad­GFP­DC group (not significantly different), and the two were significantly higher than the non­transfection group (P<0.05). The optimal effector to target (E:T) ratio was determined to be 40:1. However, at the same E:T ratio, the cytotoxic activity of PSMA­DC­T against the LNCap cells was markedly stronger than its activity against the other target cells (DU145 and 22RV; P<0.05); furthermore, the the cytotoxic activity of PSMA-DC-T against the LNCap cells was significantly higher than the anti­LNCap effect of DC­T cells in other groups (P<0.05). In vitro experiments indicated that mature DCs transfected with Ad­PSMA secreted high concentrations of IL­12 and elicited potent antitumor immune responses targeting PSMA­expressing cells by stimulating the cytotoxic activity of CTLs.

Transarterial chemoembolization versus hepatic resection in hepatocellular carcinoma treatment: a meta-analysis.

BACKGROUND: A number of cohort studies have compared the outcomes of transarterial chemoembolization (TACE) and hepatic resection (HR) in the treatment of hepatocellular carcinoma (HCC). However, the effect of TACE versus HR remains controversial. Therefore, we conducted a meta-analysis to assess the effectiveness of TACE and HR in HCC treatment. MATERIALS AND METHODS: PubMed, Embase, Web of Science, Scopus, ClinicalTrials.gov, and Cochrane library were searched from their inception until February 27, 2015 for relevant studies. The literature search was updated on May 25, 2015. Eligible studies were cohort studies comparing the survival outcomes between HCC patients undergoing TACE and HR. The primary outcome was overall survival (OS). Secondary outcomes were the recurrence rate and prognostic factors for OS. The risk ratio (RR) was used for the meta-analysis and was expressed with 95% confidence intervals (CIs). RESULTS: This meta-analysis included eleven cohort studies with 6,297 patients, all treated with TACE or HR. Pooled estimates showed that, compared with TACE, HR significantly improved the 3-year OS (RR =0.77; 95% CI, 0.63-0.93; P=0.009). TACE and HR had similar effects on OS after 1 year (RR =0.94; 95% CI, 0.86-1.01; P=0.103), 2 years (RR =0.50; 95% CI, 0.21-1.19; P=0.114), 4 years (RR =0.61; 95% CI, 0.58-1.10; P=0.174), and 5 years (RR =0.77; 95% CI, 0.59-1.01; P=0.06). There was no significant difference between the 3-year (RR =1.31; 95% CI, 0.65-2.64; P=0.457) and 5-year recurrence rates (RR =1.14; 95% CI, 0.69-1.89; P=0.597) in the TACE and HR groups. Age (>65 vs ≤65 years; hazard ratio =0.99; 95% CI, 0.98-1.00; P=0.000), sex (male vs female; hazard ratio =0.79; 95% CI, 0.65-0.96; P=0.02), treatment method (TACE vs HR; hazard ratio =1.90; 95% CI, 1.46-2.46; P=0.000), and Eastern Cooperative Oncology Group performance score (≥1 vs 0; hazard ratio =1.69; 95% CI, 1.22-2.33; P=0.002) were independent predictors for OS. CONCLUSION: This meta-analysis suggests that the TACE and HR likely have similar effects in the treatment of HCC patients in terms of OS and recurrence rate. However, this conclusion should be interpreted cautiously due to the presence of further subgroup analyses with respect to outcomes in patients with different liver statuses (Barcelona Clinic Liver Cancer stage A or stage B).

Synergistic effects of snail and quercetin on renal cell carcinoma Caki-2 by altering AKT/mTOR/ERK1/2 signaling pathways.

Renal cell carcinoma has become the most common subtype of kidney cancer, and has the highest propensity to manifest as metastatic disease. Because of lack of knowledge in events that correlated with tumor cell migration and invasion, few therapeutic options are available. Therefore, in current study, we explore the anti-tumoral effect of a potential chemopreventive natural product, quercetin, combined with anti-sense oligo gene therapy (inhibiting Snail gene). We found that either one of them had the remarkable effects in suppressing cell proliferation and migration, inducing cell cycle arrest and apoptosis in a ccRCC cell line, Caki-2 cells. The combination of both means provides even strong suppressive effects toward these ccRCC cells. Our study, for the first time, provides the possibility of using a novel treatment for renal cancer, by combining natural product and gene therapy.

Antiproliferative activity of rosamultic acid is associated with induction of apoptosis, cell cycle arrest, inhibition of cell migration and caspase activation in human gastric cancer (SGC-7901) cells.

BACKGROUND: Gastric cancer is the second leading cause of cancer related deaths after lung cancer globally. Among natural products, natural triterpenes represent a structurally diverse group of organic compounds with potent antitumor activity. PURPOSE: The objective of the present research work demonstrated the antiproliferative and apoptotic activity of rosamultic acid, a natural triterpenoid, in human gastric cancer (SGC-7901) cells. Its effect on cellular morphology, cell cycle arrest, DNA fragmentation and expression levels of caspase-3, caspase-8 and caspase-9 were also determined. METHODS: Antiproliferative activity of rosamultic acid was evaluated by MTT assay. Phase contrast, fluorescence microscopy as well as flow cytometry using Hoechst 33342, acridine orange/ethidium bromide and Annexin V-FITC as cellular probes were used to evaluate the induction of apoptosis by rosamultic acid. Protein level expressions were analyzed by western blot analysis. RESULTS: The results revealed that rosamultic acid induced dose-dependent as well as time dependent cytotoxic effects in SGC-7901 gastric cancer cells. It also led to a reduction in clonogenic activity along with inhibiting the cell migration. Characteristic features of apoptosis induced by rosamultic acid were observed and quantified. Cell cycle arrest at sub-G1 phase was induced by rosamultic acid along with downregulation of expression levels of CDK4, CDK6 and cyclin D1. Rosamultic acid also significantly led to the activation of caspase-3, -8 and -9 during the 48 h treatment along with cleaving PARP in a dose-dependent manner. DNA fragmentation following rosamultic acid treatment was also observed in these cells. CONCLUSION: The current study strongly reveals that rosamultic acid inhibits gastric cancer proliferation by inducing apoptosis mediated through cell cycle arrest, downregulation of cell cycle related protein expressions, inhibition of cell migration, DNA damage, and activation of caspases.

Association between cytochrome P450 1A1 (CYP1A1) gene polymorphisms and the risk of renal cell carcinoma: a meta-analysis.

Cytochrome P450 1A1 (CYP1A1) usually metabolizes carcinogens to their inactive derivatives but occasionally converts the chemicals to more potent carcinogens. To date, many studies have evaluated the association between the CYP1A1 MspI and Ile462Val polymorphisms and renal cell carcinoma (RCC) risk, but the results have been conflicting. To more precisely evaluate the potential association, we carried out a meta-analysis of seven published case-control studies. The meta-analysis indicated that the MspI polymorphism was associated with an increased RCC risk (allele model: OR = 1.49, 95%CI 1.03-2.16; homozygous model: OR = 1.64, 95%CI 1.13-2.40; dominant model: OR = 1.72, 95%CI 1.07-2.76). No significant associations were found for the Ile462Val polymorphism for all genetic models. When stratified by smoking status, smokers carrying the variant Vt and Val allele were more susceptible to RCC (Vt allele: OR = 3.37, 95%CI = 2.24-5.06; Val allele: OR = 2.07, 95%CI = 1.34-3.19). These data indicate that the CYP1A1 MspI polymorphism significantly increased RCC risk, while the Ile462Val polymorphism was not associated with RCC. Among smokers, individuals with the CYP1A1 Vt allele and Val allele showed a significantly increased risk of RCC. More well-designed studies with larger samples are warranted to show the underlying mechanisms of CYP1A1 in the development of RCC.

Heat-shock protein 70 as a tumor antigen for in vitro dendritic cell pulsing in renal cell carcinoma cases.

Immunological functions of heat shock proteins (HSPs) have long been recognized. In this study we aimed to efficiently purify HSP70 from renal cell carcinoma and test it as a tumor antigen for pulsing dendritic cells in vitro. HSP70 was purified from renal cell carcinoma specimens by serial column chromatography on Con A-sepharose, PD-10, ADP-agarose and DEAE-cellulose, and finally subjected to fast protein liquid chromatography (FPLC). Dendritic cells derived from the adherent fraction of peripheral blood mononuclear cells were cultured in the presence of IL-4 and GM-CSF and exposed to tumor HSP70. After 24 hours, dendritic cells were phenotypically characterized by flow cytometry. T cells obtained from the non-adherent fraction of peripheral blood mononuclear cells were then co-cultured with HSP70-pulsed dendritic cells and after 3 days T cell cytotoxicity towards primary cultured renal cell carcinoma cells was examined by Cell Counting Kit-8 assay. Dendritic cells pulsed in vitro with tumor-derived HSP70 expressed higher levels of CD83, CD80, CD86 and HLA-DR maturation markers than those pulsed with tumor cell lysate and comparable to that of dendritic cells pulsed with tumor cell lysate plus TNF-α. Concomitantly, cytotoxic T-lymphocytes induced by HSP70-pulsed dendritic cells presented the highest cytotoxic activity. There were no significant differences when using homologous or autologous HSP70 as the tumor antigen. HSP70 can be efficiently purified by chromatography and induces in vitro dendritic cell maturation in the absence of TNF-α. Conspecific HSP70 may effectively be used as a tumor antigen to pulse dendritic cells in vitro.

Effects of doxorubicin and gemcitabine on the induction of apoptosis in breast cancer cells.

Breast cancer is the most frequently diagnosed cancer and the leading cause of cancer-related mortality in females worldwide. The efficacy of chemotherapeutic drugs on breast cancer is hindered by many factors, including that cancer stem-like side population (SP) cells may contribute to tumorigenesis and resistance to chemotherapy. Doxorubicin and gemcitabine are two of the most effective and widely used chemotherapeutic agents for the treatment of various human malignancies. To the best of our knowledge, the effects of doxorubicin and gemcitabine on breast cancer SP cells are poorly understood. In the present study, we examined the potential roles of doxorubicin and gemcitabine in breast cancer main population (MP) and SP cells, and the mechanisms of doxorubicin and gemcitabine. The results showed that doxorubicin and gemcitabine decreasede proliferation, and increased apoptosis in the MCF7 MP and SP cells in vitro. Furthermore, doxorubicin and gemcitabine inhibited tumor growth and improved the survival rate of mice in vivo. Additionally, the mechanisms of doxorubicin and gemcitabine in MCF7 MP and SP cells were determined.

Impact of IL-2 and IL-2R SNPs on proliferation and tumor- killing activity of lymphokine-activated killer cells from healthy chinese blood donors.

One of the goals of tumor immunotherapy is to generate immune cells with potent anti-tumor activity through in vitro techniques using peripheral blood collected from patients. However, cancer patients generally have poor immunological function. Thus using patient T cells, which have reduced in vitro proliferative capabilities and less tumor cell killing activity to generate lymphokine-activated killer (LAK) cells, fails to achieve optimal clinical efficacy. Interleukin-2 (IL-2) is a potent activating cytokine for both T cells and natural killer cells. Thus, this study aimed to identify optimal donors for allogeneic LAK cell immunotherapy based on single nucleotide polymorphisms (SNP) in the IL-2 and IL-2R genes. IL-2 and IL-2R SNPs were analyzed using HRM- PCR. LAK cells were derived from peripheral blood mononuclear cells by culturing with IL-2. The frequency and tumor-killing activity of LAK cells in each group were analyzed by flow cytometry and tumor cell killing assays, respectively. Regarding polymorphisms at IL-2-330 (rs2069762) T/G, LAK cells from GG donors had significantly greater proliferation, tumor-killing activity, and IFN-γ production than LAK cells from TT donors (P<0.05). Regarding polymorphisms at IL-2R rs2104286 A/G, LAK cell proliferation and tumor cell killing were significantly greater in LAK cells from AA donors than GG donors (P<0.05). These data suggest that either IL- 2-330(rs2069762)T/G GG donors or IL-2R rs2104286 A/G AA donors are excellent candidates for allogeneic LAK cell immunotherapy.

Suppression of tumor necrosis factor receptor-associated protein 1 expression induces inhibition of cell proliferation and tumor growth in human esophageal cancer cells.

Tumor necrosis factor receptor-associated protein 1 (TRAP1) is a molecular chaperone involved in multidrug resistance and antiapoptosis in some human tumors, but its regulatory mechanisms have not been revealed in esophageal squamous cell carcinoma (ESCC). In this study, 138 specimens of ESCC were analyzed. TRAP1 was overexpressed in ESCC, particularly in poorly differentiated tumors. To further explore the molecular regulatory mechanism, we constructed specific small interfering RNA-expressing vectors targeting Trap1, and knocked down Trap1 expression in the esophageal cancer cell lines ECA109 and EC9706. Knockdown of Trap1 induced increases in reactive oxygen species and mitochondrial depolarization, which have been proposed as critical regulators of apoptosis. The cell cycle was arrested in G2/M phase, and in vitro inhibition of cell proliferation was confirmed with 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-tetrazolium bromide and bromodeoxyuridine assays. Furthermore, re-expression of TRAP1 in Trap1 small interfering RNA-transfected ESCC cells restored cell proliferation and cell apoptosis. Bioluminescence of subcutaneously xenografted ESCC tumor cells demonstrated significant inhibition of in vivo tumor growth by Trap1 knockdown. This study shows that TRAP1 was overexpressed in most patients with ESCC, and caused an increase in antiapoptosis potency. TRAP1 may be regarded as a target in ESCC biotherapy.

Relationship of PTTG expression with tumor invasiveness and microvessel density of pituitary adenomas: a meta-analysis.

AIMS: Many existing studies have demonstrated that pituitary tumor transforming gene (PTTG) expression may contribute to the development of pituitary adenomas (PAs), but individually published studies showed inconclusive results. This meta-analysis aimed to derive a more precise estimation of the relationships of PTTG expression with tumor invasiveness and microvessel density of pituitary adenomas. METHODS: We searched CISCOM, CINAHL, Web of Science, PubMed, Google Scholar, EBSCO, Cochrane Library, and CBM databases from inception through September 1st, 2013. Meta-analysis was performed using the STATA 12.0 software. The crude odds ratio (OR) with 95% confidence interval (CI) was calculated. RESULTS: Fifteen clinical cohort studies were included with a total of 752 pituitary adenoma patients. The meta-analysis results revealed that patients with invasive pituitary adenomas had higher positive expression of PTTG than those of noninvasive patients (OR=6.68, 95% CI=3.72-11.99, p<0.001). We also found a significant difference in the microvessel density between invasive and noninvasive patients (OR=1.81, 95% CI=0.39-3.23, p<0.001). No publication bias was detected in this meta-analysis (all p>0.05). CONCLUSION: The present meta-analysis suggests that PTTG expression may be associated with tumor invasiveness and microvessel density of pituitary adenomas. Thus, detection of PTTG expression may be useful for the prediction of malignancy degree in pituitary adenomas.

Association between MDM2 SNP309 T>G and risk of gastric cancer: a meta-analysis.

BACKGROUND: As a negative regulator of P53, MDM2 plays an important role in carcinogenesis; a polymorphism in its promoter region. SNP309 T>G, is known to increase the expression of MDM2, thus being considered related to higher susceptibility to neoplasia. However, no agreement has been achieved regarding its effects on gastric cancer. METHODS: The present systematic meta-analysis was performed based on comprehensive literature search from Pubmed, Web of science and CBM databases. RESULTS: It was suggested from 6 independent studies that the GG genotype is associated with a significantly increased risk of gastric cancer (Recessive: OR = 1.43, 95% CI = 1.08-1.91, P = 0.013), and subgroup analysis also confirmed the relationship (English publications-recessive model: OR = 1.45, 95% CI = 1.10-1.91, P = 0.009; Studies in China-recessive model: OR = 1.58, 95% CI = 1.08-2.30, P = 0.017). No publication bias was detected. CONCLUSION: The meta-analysis indicated a significant inverse association between GG genotype carriage and elevated risk of gastric cancer. However, more studies and detailed information are needed to fully address the topic.

[Effect of bufalin on cellular proliferation and apoptosis in human esophageal squamous carcinoma EC9706 cells].

OBJECTIVE: To investigate the effect of bufalin on nucleus-mitochondria localization of human telomerase reverse transcriptase(hTERT) by exploring its effect on proliferation and apoptosis in human esophageal squamous carcinoma EC9706 cells. METHODS: EC9706 cells were treated with bufalin at various concentrations, and then the cell growth inhibition of EC9706 cells was examined by CCK-8 assay and the 50% inhibitory concentration (IC(50)) was calculated.Cell cycle analysis was performed by flow cytometry with PI staining, and nucleus morphology of apoptosis were observed by fluorescence microscopy with Hoechst 33342 staining. The apoptotic index was measured by flow cytometry with Annexin V-FITC/PI double staining. hTERT subcellular localization and protein expression were determined by Western blotting and multiple immunofluorescence labling combined with laser confocal scanning microscopy. RESULTS: The proliferation of EC 9706 cells was significantly inhibited by bufalin along with the increase of processing time and concentrations (p<0.01). After the EC9706 cells were exposed to 100 nmol/L bufalin,the number of cells gradually decreased in G(1) phase and increased in S and G(2)/M phases(p<0.05). The typical nucleus morphological changes of apoptosis were observed and the apoptotic index was increased(p<0.01). The expression of hTERT decreased in nucleus but increased in mitochondria(p<0.05). CONCLUSIONS: Bufalin can inhibit the proliferation of human esophageal squamous carcinoma EC9706 cells in a time- and dose-dependent manner. It can arrest cell cycle in S and G(2)/M phases and induce the apoptosis of EC 9706 cells. hTERT is localized in both nucleus and mitochondria,and can be partially translocated from nucleus to mitochondria during the bufalin-induced apoptosis.

Low molecular weight chitosan-coated liposomes for ocular drug delivery: in vitro and in vivo studies.

In this study, low molecular weight chitosan coated liposomes (LCHL) were designed and prepared for ocular drug delivery, the coating mechanism was studied, and in vitro and in vivo characterization was conducted. The effects of molecular weight and concentration of low molecular weight chitosan on the liposomal coating were studied. The numeric relations between coating variables and coating efficiency were established using a mathematical model. Morphology of LCHL was examined by transmission electron microscopy (TEM). Cytotoxicity and cell internalization of FITC-BSA labeled LCHL in a rabbit conjunctival epithelium (RCE) cell line were studied. Cyclosporin A (CsA) was encapsulated as a model drug, and in vitro drug release and in vivo drug absorption were investigated. LCHL demonstrated low toxicity to RCE cells. In vitro drug release measurement showed that LCHL had a delayed release profile compared with non-coated liposomes. In vivo study in rabbits showed that the concentrations of CsA in cornea, conjunctiva, and sclera were remarkably increased by LCHL. In conclusion, LCHL might be a potential ocular drug carrier with characteristics such as prolonged drug retention, enhanced drug permeation, and biocompatibility.