Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0598934 (tumor growth)
 58,965 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Anticancer agents that selectively kill tumor cells and spare normal tissues are urgently needed. Here, we engineered a cell-permeable peptidomimetic, shepherdin, modeled on the binding interface between the molecular chaperone Hsp90 and the antiapoptotic and mitotic regulator, survivin. Shepherdin makes extensive contacts with the ATP pocket of Hsp90, destabilizes its client proteins, and induces massive death of tumor cells by apoptotic and nonapoptotic mechanisms. Conversely, shepherdin does not reduce the viability of normal cells, and does not affect colony formation of purified hematopoietic progenitors. Systemic administration of shepherdin in vivo is well tolerated, and inhibits human tumor growth in mice without toxicity. Shepherdin could provide a potent and selective anticancer agent in humans.
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PMID:Rational design of shepherdin, a novel anticancer agent. 1589 66

Conditionally replicating adenoviruses (CRAds) represent a promising new modality for the treatment of cancer. A key contribution in this regard was the introduction of tumor-selective viral replication for amplification of the initial inoculum. Specifically, following cellular infection, the virus replicates selectively in the infected tumor cells and kills the cells by cytolysis. Next, the progeny virions infect surrounding target cells, replicate and eradicate the infected tumor cells, leaving normal cells unaffected. However, to date there have been two limitations to clinical application of these CRAd agents; i.e., both infectivity and tumor specificity are poor. Survivin protein is a novel member of the inhibitor of apoptosis (IAP) protein family, which plays an important role in the survival of cancer cells and progression of malignancies. Previous data have shown the survivin promoter has high activities in multiple cancer cells with a low activity in mouse liver. In this study, we propose an improved CRAd agent to circumvent the obstacles. We constructed a novel CRAd agent, CRAd-Survivin-RGD, which contains both the survivin promoter (either the short version, S-S, or the long version, S-L) to selectively drive E1 gene expression in tumor cells and a capsid modification and RGD4C to specifically enhance the tumor infectivity of CRAd agents. Both CRAd agents (S-S and S-L) showed high replication rates in the breast cancer cell line, MDA-MB-361, and low promoter activity in both normal mouse and human liver, thus signifying the CRAd agents have the phenotype of 'tumor on/liver off'. In cytocidal experiments, the CRAd agents demonstrated a high cytocidal effect on multiple cancer cell lines, including the breast cancer cell line, MDA-MB-231; the glioma cell line, D65, the melanoma cell line, MEL-28; and mesothelioma, Meso2374. The results also showed the tumor growth was dramatically inhibited by intertumoral administration of the CRAd agents in a breast cancer (MDA-MB-361) xenograft animal model. These data clearly demonstrate that CRAd-Survivin-RGD is a potential novel therapeutic agent for treatment in many, but not all, human cancers.
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PMID:Incorporating the survivin promoter in an infectivity enhanced CRAd-analysis of oncolysis and anti-tumor effects in vitro and in vivo. 1594 65

Although a conditionally replicating adenovirus (CRA) exhibiting cancer-selective replication and induction of cell death is an innovative potential anticancer agent, current imperfections in cancer specificity and efficient viral replication limit the usefulness of this technique. Here, we constructed survivin-responsive CRAs (Surv.CRAs), in which expression of the wild-type or mutant adenoviral early region 1A (E1A) gene is regulated by the promoter of survivin, a new member of the inhibitor of apoptosis gene family. We explored the cancer specificity and effectiveness of viral replication of Surv.CRAs, evaluating their potential as a treatment for cancer. The survivin promoter was strongly activated in all cancers examined at levels similar to or even higher than those seen for representative strong promoters; in contrast, low activity was observed in normal cells. Surv.CRAs efficiently replicated and potently induced cell death in most types of cancer. In contrast, minimal viral replication in normal cells did not induce any detectable cytotoxicity. A single injection of Surv.CRAs into a preestablished tumor expressing survivin, even at relatively low levels, induced significant tumor death and inhibition of tumor growth. Furthermore, Surv.CRAs were superior to telomerase-dependent CRAs, one of the most effective CRAs that have been examined to date, both in terms of cancer specificity and efficiency. Thus, Surv.CRAs are an attractive potential anticancer agent that could effectively and specifically treat a variety of cancers.
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PMID:Survivin-responsive conditionally replicating adenovirus exhibits cancer-specific and efficient viral replication. 1595 75

The cyclooxygenase-2 (COX-2) protein is highly expressed in a variety of human cancers and has been reported to promote tumor growth. Non-steroidal anti-inflammatory drugs such as etodolac and celecoxib have been shown to inhibit COX-2 activity and may play a role in the chemoprevention of cancer. Oxaliplatin is a third-generation platinum compound that exhibits a different spectrum of activity compared with cisplatin. Other cisplatin-resistant tumors can still respond to oxaliplatin. However, the anticancer ability of the combination of COX-2 inhibitors and oxaliplatin is still unknown. In this study, we investigated the effects of combination of COX-2 inhibitors and oxaliplatin on the cell growth and survival in human colon cancer cells. Treatments with etodolac (0.3-0.5 mM) or celecoxib (20-80 microM) for 24 h concentration-dependently induced the cytotoxicity in the RKO colon carcinoma cells. Etodolac and celecoxib did not alter the COX-2 protein levels but inhibited its enzyme activity to reduce prostaglandin E2 production. Furthermore, the cell survival was concentration-dependently decreased following oxaliplatin (1-100 microM, 24 h) treatment. Combination of oxaliplatin and etodolac additively increased the death and growth inhibition of RKO cells. Survivin, an inhibitor protein of apoptosis, mediates anti-apoptosis and promotes cell division in cancer cells. Oxaliplatin or COX-2 inhibitors significantly decreased the levels of survivin proteins. Moreover, survivin proteins were markedly diminished following co-treatment with oxaliplatin and etodolac. Together, this is the first report that combination of COX-2 inhibitors and oxaliplatin can increase the reduction of survivin protein expression, growth inhibition, and death in human colon cancer cells.
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PMID:Combination of cyclooxygenase-2 inhibitors and oxaliplatin increases the growth inhibition and death in human colon cancer cells. 1600 71

We describe the use of retrogen plasmid-based vaccine technology to break tolerance and to generate a robust, dose-dependent antibody response against the self cancer antigen, survivin. We further demonstrate that this phenomenon is due to the incorporation of the survivin antigen into the retrogen system rather than to some peculiarity unique to survivin. In contrast to other genetic immunization methods designed to produce antibody responses, the retrogen system results in a broad range of antibody isotypes, indicative of both a Th-1 and a Th-2 CD4+ response. Additional evidence of a Th-1 response is demonstrated by tumor growth inhibition in a mouse model of colon cancer metastasis. We speculate that this cost-effective technology could one day bolster or even supplant the use of monoclonal antibodies in the targeting of cell surface cancer antigens.
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PMID:A retrogen plasmid-based vaccine generates high titer antibody responses against the autologous cancer antigen survivin and demonstrates anti-tumor efficacy. 1601 31

Esophageal squamous cell carcinoma ranks among one of the most frequent cause of cancer death in the world. Understanding of the molecular mechanisms involved in the pathogenesis of esophageal cancer becomes critical to develop more effective treatments. Elevated expression of survivin in esophageal carcinoma has been reported before and suppression of survivin expression leads to many tumor cells growth inhibition. We hypothesized that downregulation of survivin would inhibit the growth of human esophageal cancer cells. RNA interference directed against survivin was introduced into a human esophageal squamous cell carcinoma cell line KYSE510. Stable clones were selected and western blot analysis was performed to detect the protein level of survivin. Tumor cell growth in vitro and in vivo was assessed by trypan blue exclusion and nude mice experiments. Annexin V/propidium iodide staining followed by flow cytometric analysis and TUNEL assay were used to detect apoptosis in cell culture and in nude mice. We found that RNA interference could efficiently and stably suppress survivin expression in KYSE510 cells. Downregulation of survivin resulted in significantly inhibition of tumor growth in vitro and in vivo. The mechanism appears to be increased induction of apoptosis. Our results suggest a potential role for the targeting of survivin in the treatments of esophageal carcinoma.
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PMID:Downregulation of survivin by RNAi inhibits the growth of esophageal carcinoma cells. 1608 95

While second mitochondria derived activator of caspase (Smac) has been described to sensitize for apoptosis, its effect on cell viability in the absence of apoptotic stimuli has remained unclear. Here, we report that Smac inhibits clonogenic tumor growth by blocking random migration and proliferation and by enhancing apoptosis in a cell density and cell type dependent manner in SH-EP neuroblastoma cells. Inhibition of clonogenic survival by overexpression of full-length or processed Smac strictly depended on low cell density, and was reversible by replatement at high density. We discovered that Smac inhibits cell motility and random migration at low cell density. In addition, Smac enhanced apoptosis and inhibited protein, but not mRNA expression of XIAP, survivin and other short-lived proteins (FLIP, p21), indicating that Smac may globally inhibit protein expression. Also, Smac inhibited proliferation and increased polynucleation with no evidence for polyploidy, cell cycle arrest or senescence indicating that Smac impaired cell division. Interestingly, inhibition of clonogenic capacity by Smac occurred independent of its apoptosis promoting activity. By demonstrating that Smac restrains clonogenic tumor growth, our findings may have important implications for control of tumor growth and/or its metastatic spread. Thus, Smac agonists may be useful in cancer therapy, for example, for tumor control in minimal residual disease. Oncogene (2005) 24, 7190-7202. doi:10.1038/sj.onc.1208876; published online 8 August 2005.
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PMID:Inhibition of clonogenic tumor growth: a novel function of Smac contributing to its antitumor activity. 1609 52

Adult T-cell leukemia (ATL), an aggressive malignancy of CD4+ T cells associated with human T-cell leukemia virus type I (HTLV-I) infection, carries a very poor prognosis because of the resistance of leukemic cells to any conventional regimen, including chemotherapy. We examined the effect of ritonavir, an HIV protease inhibitor, on HTLV-I-infected T-cell lines and primary ATL cells and found that it induced apoptosis and inhibited transcriptional activation of NF-kappaB in these cells. Furthermore, ritonavir inhibited expression of Bcl-xL, survivin, c-Myc, and cyclin D2, the targets of NF-kappaB. In nonobese diabetic/severe combined immunodeficient (NOD/SCID)/gammacnull (NOG) mice, ritonavir very efficiently prevented tumor growth and leukemic infiltration in various organs of NOG mice at the same dose used for treatment of patients with AIDS. Our data indicate that ritonavir has potent anti-NF-kappaB and antitumor effects and might be clinically applicable for treatment of ATL. These results would provide a new concept and novel platform for new drug development of leukemia and solid cancer as well.
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PMID:Efficient intervention of growth and infiltration of primary adult T-cell leukemia cells by an HIV protease inhibitor, ritonavir. 1617 65

Dehydroepiandrosterone (DHEA) is believed to have an anti-tumor effect, as well as anti-inflammatory, antioxidant, and anti-aging effects. To clarify the possible inhibitory action of DHEA on pituitary tumor cells, we tested the effects of DHEA, alone or in combination with the nuclear factor-kappaB (NF-kappaB) inhibitor parthenolide (PRT), on AtT20 corticotroph cell growth and function both in vitro and in vivo. We found that, in vitro, DHEA and PRT had potent inhibitory effects on pro-opiomelanocortin and NF-kappaB-dependent gene expression. They also suppressed the transcription activity of survivin, a representative anti-apoptotic factor, and induced apoptosis in this cell line. Furthermore, using BALB/C nude mice with xenografts of AtT20 cells in vivo, we found that the combined administration of DHEA and PRT significantly attenuated tumor growth and survivin expression. The treatment also decreased the elevated plasma corticosterone levels and ameliorated the malnutrition induced by tumor growth. Altogether, these results suggested that combined treatments of DHEA and PRT potently inhibit the growth and function of corticotroph tumor cells both in vitro and in vivo. This effect may, at least partly, be caused by the suppressive effects of these compounds, such as survivin and other inhibitor of apoptosis proteins, on NF-kappaB-mediated gene transcription.
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PMID:Suppressive effects of dehydroepiandrosterone and the nuclear factor-kappaB inhibitor parthenolide on corticotroph tumor cell growth and function in vitro and in vivo. 1646 58

A library of 2'-methoxyethyl-modified antisense oligonucleotides (2'MOE ASO) targeting 1,510 different genes has been developed, validated, and used to identify cell cycle regulatory genes. The most effective molecular target identified was Eg5 (kinesin-like-1), which when inhibited gave the largest increase in 4N DNA in various tumor cells. The Eg5 ASO reduced Eg5 levels, inhibited proliferation, increased apoptosis, and altered the expression of other cell cycle proteins, including survivin and Aurora-A. To examine the therapeutic utility of the Eg5 ASO, the compound was also evaluated in xenograft models. Treatment with Eg5 ASO produced a statistically significant reduction of tumor growth, reduction in Eg5 expression in the tumors, and changes in histone phosphorylation, consistent with a loss of Eg5 protein expression. These data show, for the first time, the utility of a 2'MOE ASO library for high-throughput cell culture-based functional assays and suggest that an Eg5 ASO also has potential in a therapeutic strategy.
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PMID:Use of a chemically modified antisense oligonucleotide library to identify and validate Eg5 (kinesin-like 1) as a target for antineoplastic drug development. 1648 5


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