Apoptosis In Xenograft Tumors Research Articles

Antitumor effect of IL-12 gene-modified bone marrow mesenchymal stem cells combined with Fuzheng Yiliu decoction in an in vivo glioma nude mouse model

BackgroundGlioma is a complex cancer with a high morbidity and high mortality. Bone marrow mesenchymal stem cells (BMSCs) have shown promise as an excellent cell/drug delivery vehicle for gene-targeted therapy; however, maintaining genetic stability and biological activity remains difficult. Furthermore, whether BMSCs support or inhibit tumor growth remains debated. This study investigated whether a traditional Chinese medicine fomular, Fuzheng Yiliu decoction (FYD) had a synergistic antitumor effect with IL-12 gene-modified BMSCs in glioma-bearing nude miceMethodsThe lentivirus-mediated IL-12 gene was transfected into primarily cultured BMSCs. A total of 72 BALB/c nude mice were used to establish xenograft models with glioma U251 cells and were divided into groups (n = 12) including blank control group, nude mouse model group (model group), lentiviral transfection of BMSC group with no gene loading (BMSC group), IL-12 lentivirus-transfected BMSC group (IL-12 + BMSC group), FYD treatment group (FYD group), and FYD treatment in IL-12 lentivirus-transfected BMSC group (FYD + IL-12 + BMSC group).. After treatment for 14 days, all mice were sacrificed to collect tumor tissue and serum for more detection, such as distribution of BMSCs, cell apoptosis in xenograft tumors, serum IL-12 and INF-γ levels, mouse weight and tumor volume were measuredResultsThere were significantly more apoptotic cells in tumor tissue in IL-12 gene transfected group, FYD treatment group and FYD combining with IL-12 gene transfected group than that in the model group (P < 0.05). The FYD + IL-12 + BMSC group showed significantly higher Bax and lower Bcl-2 expression (P < 0.05), and serum IL-12 and INF-γ levels (P < 0.05) were higher than that in all other groups. After the intervention, this group also showed a strong inhibitory effect against tumor growth (P < 0.05)ConclusionsThis study suggested FYD treatment combined with IL-12 gene-modified BMSCs shows synergistic antitumor effect in glioma-bearing nude mice.

Circ_0007444 Inhibits the Progression of Ovarian Cancer via Mediating the miR-570-3p/PTEN Axis.

PurposeSome circular RNAs have been found to be effective therapeutic targets for OC. However, the biological function of circ_0007444 in OC is still unknown. Thus, this study investigated the role of circ_0007444 in OC progression.Methodscirc_0007444 expression was monitored in 87 OC patients and OC cells by quantitative real-time polymerase chain reaction. An in vitro study was performed to research the biological function of circ_0007444, including cell counting kit-8 assay, flow cytometry, wound healing assay, and transwell experiment. Luciferase reporter gene assay and RNA immunoprecipitation assay were used to reveal the interaction between circ_0007444, miR-570-3p, and PTEN. PTEN protein expression was determined by Western blot. In vivo study was performed using nude mice. Ki67, PTEN expression, and apoptosis in xenograft tumors was respectively researched by immunohistochemistry and Tunel assay.Resultscirc_0007444 was down-regulated in 87 OC patients, which was related to advanced tumor stage and grade, large tumor size, and low 60-month percent survival (P<0.05 or P<0.01). circ_0007444 inhibited proliferation, migration, and invasion, and promoted apoptosis of OC cells (P<0.01). circ_0007444 promoted PTEN expression via sponging miR-570-3p. miR-570-3p up-regulation and PTEN down-regulation reversed the inhibitory effect of circ_0007444 on OC cells malignant phenotype (P<0.01). circ_0007444 inhibited OC growth in vivo. In xenograft tumor, circ_0007444 decreased Ki67 expression but increased PTEN expression and apoptosis.Conclusioncirc_0007444 is a tumor suppressor in OC, which inhibits OC progression by mediating the miR-570-3p/PTEN. circ_0007444 can be a potential candidate for targeted therapy of OC.

α-Pinene Inhibits Human Prostate Cancer Growth in a Mouse Xenograft Model

Background: α-Pinene is one of the most widely found terpenoids in nature. Substantial evidence shows that α-pinene has cancer prevention properties. In this study, the PC-3 cell line was used to establish subcutaneous xenograft tumors in nude mice. Methods: Cytotoxicity was measured with the MTT assay, and apoptosis and cell cycle analyses were conducted using flow cytometry in vitro. The PC-3 cell line was used to establish subcutaneous xenograft tumors in nude mice. Results: We found that treatment with α-pinene significantly inhibited human prostate cancer cell growth and induced apoptosis and cell cycle arrest in the cell line-based model. Furthermore, tumor progression was inhibited more in mice treated with α-pinene than in control mice. We detected less Ki67 and proliferation cell nuclear antigen in paraffin sections from xenograft tumor specimens taken from α-pinene-treated mice than in those from the control group. Meanwhile, α-pinene treatment induced apoptosis in xenograft tumors as determined by the TUNEL assay. Conclusions: These data strongly suggest that α-pinene inhibits prostate cancer growth in a xenograft model and may be an effective therapeutic agent for prostate cancer treatment.

MTORC2 promotes cell survival through c-Myc-dependent up-regulation of E2F1.

Previous studies have reported that mTORC2 promotes cell survival through phosphorylating AKT and enhancing its activity. We reveal another mechanism by which mTORC2 controls apoptosis. Inactivation of mTORC2 promotes binding of CIP2A to PP2A, leading to reduced PP2A activity toward c-Myc serine 62 and, consequently, enhancement of c-Myc phosphorylation and expression. Increased c-Myc activity induces transcription of pri-miR-9-2/miR-9-3p, in turn inhibiting expression of E2F1, a transcriptional factor critical for cancer cell survival and tumor progression, resulting in enhanced apoptosis. In vivo experiments using B cell-specific mTORC2 (rapamycin-insensitive companion of mTOR) deletion mice and a xenograft tumor model confirmed that inactivation of mTORC2 causes up-regulation of c-Myc and miR-9-3p, down-regulation of E2F1, and consequent reduction in cell survival. Conversely, Antagomir-9-3p reversed mTORC1/2 inhibitor-potentiated E2F1 suppression and resultant apoptosis in xenograft tumors. Our in vitro and in vivo findings collectively demonstrate that mTORC2 promotes cell survival by stimulating E2F1 expression through a c-Myc- and miR-9-3p-dependent mechanism.

Thromboxane synthase expression and correlation with VEGF and angiogenesis in non-small cell lung cancer

Background: Thromboxane synthase (TXS) metabolizes prostaglandin H2 into thromboxanes, which are biologically active on cancer cells. TXS over-expression has been reported in a range of cancers, and associated with angiogenesis and poor outcome. TXS has been identified as a potential therapeutic target in NSCLC. This study examines a link between TXS expression, angiogenesis, and survival in NSCLC. Methods: TXS and VEGF metabolite levels were measured in NSCLC serum samples (n=46) by EIA. TXB2 levels were correlated with VEGF. A 204-patient TMA was stained for TXS, VEGF, and CD-31 expression. Expression was correlated with a range of clinical parameters, including overall survival. TXS expression was correlated with VEGF and CD-31. Stable TXS clones were generated and the effect of overexpression on tumor growth and angiogenesis markers was examined in-vitro and in-vivo (xenograft mouse model). Results: Serum TXB2 levels were correlated with VEGF (p<0.05). TXS and VEGF were expressed to a varying degree in NSCLC tissue. TXS was associated with VEGF (p<0.0001) and microvessel density (CD-31; p<0.05). TXS and VEGF expression levels were higher in adenocarcinoma (p<0.0001) and female patients (p<0.05). Stable overexpression of TXS increased VEGF secretion in-vitro. While no significant association with patient survival was observed for either TXS or VEGF in our patient cohort, TXS overexpression significantly (p<0.05) increased tumor growth in-vivo. TXS overexpression was also associated with higher levels of VEGF, microvessel density, and reduced apoptosis in xenograft tumors. Conclusion: TXS promotes tumor growth in-vivo in NSCLC, an effect which is at least partly mediated through increased tumor angiogenesis.

Abstract 4089: Calmodulin antagonists inhibit cholangiocarcinoma tumorigenesis independent of gemcitabine by the activating of caspase 2

Abstract Cholangiocarcinoma is a highly malignant tumor with limited therapeutic options. Gemcitabine (GMT) is currently used as a first line chemotherapeutical reagent for many cancers, including cholangiocarcinoma. However, it is often used in combination with other therapeutical strategies, due to high toxicity of GMT. We have previously reported that antagonists of calmodulin (CaM), including tamoxifen (TMX), trifluoperazine (TFP) and W7, induce apoptosis of cholangiocarcinoma cells and reduce cholangiocarcinoma tumorigenesis in mice. In the present studies, we determined the effect of combination therapy of TMX and GMT on cholangiocarcinoma tumorigenesis and investigated the mechanisms responsible for their efficacy. The effect of TMX and GMT on cholangiocarcinoma cell growth and apoptosis in vitro was determined by MTS and Annexin V staining analysis. The expression/activation of apoptotic signaling molecules were assessed by Western blot analysis. A nude mouse xenograft model was utilized for in vivo cholangiocarcinoma tumorigenesis as we previously reported. TMX (15mg/kg), GMT (15mg/kg) and combination of both were administrated by intraperitoneal injection. Tumor growth was measured every 3 days. Apoptosis in xenograft tumors was determined by TUNEL and cleaved caspase 3 staining. GMT inhibited cell growth and induced apoptosis of cholangiocarcinoma cells in a concentration-dependent manner. TMX enhanced GMT-induced apoptosis and GMT inhibition of cell growth in cholangiocarcinoma cells. GMT (15mg/kg, every third day) inhibited cholangiocarcinoma tumorigenesis in nude mice by 50%. TMX (15mg/kg, two out of three days) enhanced the inhibitory effect of GMX on tumorigenesis by 33%. The inhibition of tumor growth correlated with enhanced apoptosis in tumor tissues. To elucidate the mechanisms underlying the additive effects of TMX on GMT-induced apoptosis, we determined activation of caspases in cholangiocarcinoma cells exposed to GMT, TMX or both. Activation of caspase 9 and caspase 3, as well as cytochrome c release to the cytosol were demonstrated in cells exposed to either reagent alone. By contrast, TMX but not GMT activated caspase 2. Pharmacologic inhibition of caspase 2 activation decreased TMX-, but not GMT-, induced activation of caspase 3 and apoptosis of cholangiocarcinoma cells. Similarly, activation of caspase 2 was found in tumors from TMX-treated mice, but not GMT-treated mice. Therefore, the enhanced effect of TMX on GMT-induced cholangiocarcinoma cell death is partially mediated by activation of caspase 2. TMX and GMT both induce apoptosis and inhibit cholangiocarcinoma tumorigenesis, which may be attributed to the activation of distinct apoptosis signals by TMX and GMT. Our studies provide in vivo evidence and molecular insight to support the use of TMX and GMT in combination as an effective therapy for cholangiocarcinoma. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 4089. doi:10.1158/1538-7445.AM2011-4089

A Potent and Orally Active Antagonist (SM-406/AT-406) of Multiple Inhibitor of Apoptosis Proteins (IAPs) in Clinical Development for Cancer Treatment

We report the discovery and characterization of SM-406 (compound 2), a potent and orally bioavailable Smac mimetic and an antagonist of the inhibitor of apoptosis proteins (IAPs). This compound binds to XIAP, cIAP1, and cIAP2 proteins with K(i) of 66.4, 1.9, and 5.1 nM, respectively. Compound 2 effectively antagonizes XIAP BIR3 protein in a cell-free functional assay, induces rapid degradation of cellular cIAP1 protein, and inhibits cancer cell growth in various human cancer cell lines. It has good oral bioavailability in mice, rats, non-human primates, and dogs, is highly effective in induction of apoptosis in xenograft tumors, and is capable of complete inhibition of tumor growth. Compound 2 is currently in phase I clinical trials for the treatment of human cancer.