Patients with localized prostate cancer can usually achieve initial response to conventional treatment. However, most of them will inevitably progress to advanced disease stage. There is a clear need to develop innovative and effective therapeutics for prostate cancer. Mouse survivin T34A (mS-T34A) is a phosphorylation-defective Thr34 → Ala dominant negative mutant, which represents a potential promising target for cancer gene therapy. This study was designed to determine whether mS-T34A plasmid encapsuled by DOTAP-chol liposome (Lip-mS) has the anti-tumor activity against prostate cancer, if so, to further investigate the possible mechanisms.
In vitro, TRAMP-C1 cells were transfected with Lip-mS and examined for apoptosis by PI staining and flow cytometric analysis. In vivo, subcutaneous prostate cancer models were established in C57BL/6 mice, which were randomly assigned into three groups to receive i.v. administrations of Lip-mS, pVITRO2-null plasmid complexed with DOTAP-chol liposome (Lip-null) or normal saline every 2 days for eight doses. Tumor volume was measured. Tumor tissues were inspected for apoptosis by TUNEL assay. Microvessel density (MVD) was determined by CD31 immunohistochemistry. Alginate-encapsulated tumor cell test was conducted to evaluate the treatment effect on angiogenesis.
Administration of Lip-mS resulted in significant inhibition in the growth of mouse TRAMP-C1 tumors. The anti-tumor response was associated with increased tumor cell apoptosis and decreased microvessel density.
The present study may be of importance in the exploration of the potential application of Lip-mS in the treatment of a broad spectrum of tumors.
"Koike et al. demonstrated that survivin was associated with PCa cell proliferation . In addition, some studies suggested that survivin made a crucial contribution to apoptotic resistance in PCa either in vitro or in vivo [26,47]. "
[Show abstract][Hide abstract] ABSTRACT: Abnormal expression of Baculoviral inhibitor of apoptosis repeat-containing 5 (BIRC5, also called as survivin), a novel member of the inhibitor of apoptosis protein (IAP) family, has implications in many types of cancer and is considered as a new therapeutic target. We suppose that genetic variant rs9904341 in the 5[prime] UTR region of survivin gene may be associated with the development and progression of prostate cancer (PCa) in Chinese population.
TaqMan assay method was used to genotype the polymorphism in the hospital-based case--control analysis of 665 patients with PCa and 710 age-matched cancer-free controls. The genetic associations with the occurrence and progression of PCa were calculated by logistic regression.
Our results indicated that compared with GG genotypes, there was a statistically significant increased risk of PCa associated with those with CC genotypes [odds ratios (ORs) = 1.57, 95%confidence intervals (CIs) = 1.17-2.13, P = 0.004]. Moreover, stratification analysis revealed that the association was more pronounced in subgroups of nondrinkers, nonsmokers and those without a family history of cancer (all P < 0.05). In addition, we observed that PSA >= 20 was more frequent in patients carrying GC/CC genotypes than in those with a wild type genotype.
The functional survivin rs9904341 genetic variant may have a substantial influence on the PCa susceptibility and evolution.
BMC Cancer 07/2013; 13(1):356. DOI:10.1186/1471-2407-13-356 · 3.36 Impact Factor
"This may involve upregulated survivin expression during the proliferative phase, with the nonproliferative phase of angiogenesis being a transcriptional target for vascular endothelial growth factors,11,50 indicating that vascular endothelial growth factor protects endothelial cells against apoptosis during angiogenesis by upregulating survivin.12–15 Therefore, in addition to inhibiting tumor cell growth, targeted survivin may also prove to be beneficial in inducing apoptosis in proliferating endothelial cells within the tumor vasculature.17,18 "
[Show abstract][Hide abstract] ABSTRACT: Gene therapy provides a novel method for the prevention and treatment of cancer, but the clinical application of gene therapy is restricted, mainly because of the absence of an efficient and safe gene delivery system. Recently, we developed a novel nonviral gene carrier, ie, heparin-polyethyleneimine (HPEI) nanoparticles for this purpose.
HPEI nanoparticles were used to deliver plasmid-expressing mouse survivin-T34A (ms-T34A) to treat C-26 carcinoma in vitro and in vivo. According to the in vitro studies, HPEI nanoparticles could efficiently transfect the pGFP report gene into C-26 cells, with a transfection efficiency of 30.5% ± 2%. Moreover, HPEI nanoparticle-mediated ms-T34A could efficiently inhibit the proliferation of C-26 cells by induction of apoptosis in vitro. Based on the in vivo studies, HPEI nanoparticles could transfect the Lac-Z report gene into C-26 cells in vivo. Intratumoral injection of HPEI nanoparticle-mediated ms-T34A significantly inhibited growth of subcutaneous C-26 carcinoma in vivo by induction of apoptosis and inhibition of angiogenesis.
This research suggests that HPEI nanoparticle-mediated ms-T34A may have a promising role in C-26 colon carcinoma therapy.
International Journal of Nanomedicine 10/2011; 6:2419-27. DOI:10.2147/IJN.S23582 · 4.38 Impact Factor
"Survivin-T34A treatment of tumor-bearing mice resulted in inhibited tumor-induced angiogenesis and increased apoptosis.16,17,27,49 Tumor sections taken from human breast cancer transplants in mice were stained with anti-CD31 antibody to determine microvessel density.50 Survivin-T34A-treated groups showed significantly reduced microvessel density compared with controls.16 "
[Show abstract][Hide abstract] ABSTRACT: The inhibitor of apoptosis protein survivin's threonine 34 to alanine (T34A) mutation abolishes a phosphorylation site for p34(cdc2)-cyclin B1, resulting in initiation of the mitochondrial apoptotic pathway in cancer cells; however, it has little known direct effects on normal cells. The possibility that targeting survivin in this way may provide a novel approach for selective cancer gene therapy has yet to be fully evaluated. Although a flurry of work was undertaken in the late 1990s and early 2000s, only minor advances on this mutant have recently taken place. We recently described that cells generated to express a stable form of the mutant protein released this survivin-T34A to the conditioned medium. When this conditioned medium was collected and deposited on naive tumor cells, conditioned medium T34A was as effective as some chemotherapeutics in the induction of tumor cell apoptosis, and when combined with other forms of genotoxic stressors potentiated their killing effects. We hope with this review to revitalize the T34A field, as there is still much that needs to be investigated. In addition to determining the therapeutic dose and the duration of drug therapy required at the disease site, a better understanding of other key factors is also important. These include knowledge of target cell populations, cell-surface receptors, changes that occur in the target tissue at the molecular and cellular level with progression of the disease, and the mechanism and site of therapeutic action.
OncoTargets and Therapy 12/2010; 3:247-54. DOI:10.2147/OTT.S15293 · 2.31 Impact Factor
Data provided are for informational purposes only. Although carefully collected, accuracy cannot be guaranteed. The impact factor represents a rough estimation of the journal's impact factor and does not reflect the actual current impact factor. Publisher conditions are provided by RoMEO. Differing provisions from the publisher's actual policy or licence agreement may be applicable.