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)

Neuroendocrine (NE) differentiation in prostate cancer (CaP) has been reported to be an early marker associated with the development of androgen independence. The mechanisms by which CaP acquires NE properties are poorly understood. In this study, a putative role of adrenomedullin (AM) in the NE differentiation was investigated. The expression of AM and AM receptors (calcitonin receptor-like receptor (CRLR)/receptor activity modifying protein-2 and -3 (RAMP2 and RAMP3) was evaluated after experimental manipulation of androgen status. Levels of AM mRNA and immunoreactive AM (ir-AM) increased four- to sevenfold in androgen-sensitive LNCaP cells after androgen withdrawal in vitro and in LNCaP xenografts in animals after castration. Treatment of LNCaP cells with androgen analogue (dihydrotestosterone; 10(-9) M) prevented the increase in AM mRNA and ir-AM levels. Interestingly, the expression of CRLR, RAMP2 and RAMP3 is not regulated by androgen status. We demonstrate that in the presence of serum, AM is able to induce an NE phenotype in LNCaP cells via CRLR/RAMP2 and RAMP3, which includes extension of neuritic processes and expression of the neuron-specific enolase (NSE), producing cGMP in a dose-dependent manner, which is mediated by a pertussis toxin-sensitive GTP-binding protein. 8-Bromo-cGMP mimicked the effects of AM on cell differentiation. We demonstrate that AM induces a G-kinase Ialpha translocation to the nucleus. The protein kinase G inhibitor KT-5823 inhibited the neurite outgrowth induced by both AM and 8-bromo-cGMP. In noncastrated animals, administration of AM enhanced expression of NSE and chromogranin A in LNCaP xenografts with a significant increase of NSE levels in serum and no changes in tumor growth. In castrated animals, intraperitoneal injection of AM resulted in a 240+/-18% (P<0.001) increase in tumor volume 36 days after treatment, indicating that the nature of effect of AM in CaP depends on the presence or absence of endogenous androgen. Together, these results demonstrate that AM may function as a mediator of NE-like differentiation in culture as well as in vivo and indicate that its production may be important for tumor resurgence following androgen ablation.
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PMID:Adrenomedullin, an autocrine/paracrine factor induced by androgen withdrawal, stimulates 'neuroendocrine phenotype' in LNCaP prostate tumor cells. 1763 48

In the present study, four novel dienone cyclopropoxy curcumin analogs 1a-4a were synthesized by nucleophillic substitution reaction with cyclopropyl bromide. The tumor inhibitory and anti-angiogenic effects of the synthetic compounds were studied on mouse Ehrlich ascites tumor (EAT) in vivo. The compounds 1a-4a increased the life span (% ILS) of EAT bearing mice with corresponding significant reduction in ascites volume and cell number and induced apoptotic bodies in EAT cells. Anti-angiogenic studies of the compounds demonstrated significant reduction of microvessel density (MVD) in the peritoneum wall sections of mice and induced avascular zone in CAM model. Our findings demonstrate that the tumor growth inhibitory effects of synthetic dienone cyclopropoxy curcumin analogs 1a-4a could be mediated by promoting apoptosis and inhibiting tumor angiogenesis. However, the compounds need to be explored further to assess its clinical relevance.
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PMID:In vivo growth inhibitory and anti-angiogenic effects of synthetic novel dienone cyclopropoxy curcumin analogs on mouse Ehrlich ascites tumor. 1786 27

Because epigenetic alterations are believed to be involved in the repression of tumor suppressor genes and promotion of tumorigenesis in endometrial cancers and ovarian cancers, novel compounds endowed with a histone deacetylase (HDAC) inhibitory activity are an attractive therapeutic approach. Clonogenic assay in soft agar and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assays showed that many endometrial and ovarian cancer cell lines were sensitive to the growth inhibitory effect of HDAC inhibitors (HDACIs), although normal endometrial epithelial cells were viable after the treatment with the same doses of HDACIs that induced growth inhibition of endometrial and ovarian cancer cells. Cell cycle analysis indicated that their exposure to HDACIs decreased the proportion of cells in the S-phase and increased the proportion in the G0/G1 phases and/or G2/M phases of the cell cycle. Induction of apoptosis was confirmed by TUNEL assay, annexin V staining of externalized phosphatidylserine, and loss of the transmembrane potential of mitochondria. This induction occurred in concert with altered expression of genes related to cell growth, malignant phenotype, and apoptosis. In nude mice experiments, valproic acid significantly inhibited human endometrial and ovarian tumor growth without toxic side-effects. Although there are few clinical trials on these cancers, some clinical trials showed that HDACIs in well tolerated doses have significant antitumoral activities in another cancers. These results raise the possibility that HDACIs may prove particularly effective in the treatment of endometrial cancers and ovarian cancers.
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PMID:Human endometrial and ovarian cancer cells: histone deacetylase inhibitors exhibit antiproliferative activity, potently induce cell cycle arrest, and stimulate apoptosis. 1797 7

To investigate the potential effects of resistin-13-peptide on the growth, adhesion, and invasion in human breast carcinoma cells, MDA-MB-231. 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2H-tetrazolium bromide assay and colony-forming assay were used to assess the proliferation effects of resistin-13-peptide. The adhesive ability was investigated by cell adhesion assay, and the invasive potential was assessed using a transwell model. Activities of matrix metalloproteinase (MMP)-2 and MMP-9 were measured by zymography analysis and western blotting. Tissue inhibitors of metalloproteinases (TIMP)-1 and TIMP-2 were determined by western blotting. In this study, we performed in vivo experiments and determined the effect of resistin-13-peptide on tumor growth and other organs, especially ovaries in a xenograft model using the cell line studied. Resistin-13-peptide inhibited MDA-MB-231 cell growth and colony formation in a dose- and time-dependent manner. Meanwhile, the invasive and adhesive abilities of MDA-MB-231 cells were yet cut down by resistin-13-peptide in a dose-dependent manner. Resistin-13-peptide decreased the gelatinolytic activities of both MMP-2 and MMP-9 and enhanced the protein expression of TIMP-1 and TIMP-2, which were secreted from the MDA-MB-231 cells. The animal experiments found that the growth of tumors was repressed by resistin-13-peptide, which affected other organs in the same time. Especially, ovaries did not have pathological changes yet. Treatment with resistin-13-peptide is effective in suppressing tumor proliferation, adhesion, and invasion. The possible mechanism is downregulation of MMPs and upregulation of TIMPs.
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PMID:Inhibitory effects of resistin-13-peptide on the proliferation, adhesion, and invasion of MDA-MB-231 in human breast carcinoma cells. 1804 57

Multidrug resistance (MDR) is one of the major obstacles limiting the efficacy of cancer chemotherapy. Identification of new and effective MDR reversal agents is needed. In this study, the effects of polyoxyethylene 40 stearate (PS40) on MDR were evaluated via the transport of the P-glycoprotein (P-gp) substrate vinblastine sulfate (VBL) through Caco-2 cell monolayers and rat intestine tissue. The effects of PS40 on the antitumor activity of VBL were examined through 3-(4,5)-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) cytotoxicity assay and multidrug-resistant tumor-bearing mice. Results of the transport experiments showed that PS40 reduced VBL efflux. The cytotoxicity of vinblastine to K562/ADR cells was significantly enhanced when the cells were cotreated with 100 or 150 microg/mL PS40. In vivo data revealed that average tumor volume and average tumor weight were significantly less in the VBL+PS40 group than in the VBL group. The inhibition rate for tumor growth was increased from 0.06 (VBL group) to 0.84 (VBL+PS40 group). These results suggest that PS40 may be a potentially useful adjuvant to enhance the therapeutic effects of P-gp substrates.
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PMID:Polyoxyethylene 40 stearate modulates multidrug resistance and enhances antitumor activity of vinblastine sulfate. 1817 Sep 79

In our study we use nordihydroguaiaretic acid (NDGA), the naturally occurring lignan, to investigate whether it plays a role in the prevention and treatment of cancer by epigenetic modifications. The growth inhibitory effect of NDGA on human breast cancer cell lines was determined using the MTT assay (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay). It substantially inhibited the growth of human breast cancer cell lines SKBR3 and MDA-MB-435 with an estimated IC50 of 31.09+/-1.6 and 38.8+/-2.1 micromol/l respectively, after 4 days incubation with different NDGA concentrations. The in-vivo anticancer activity of NDGA was evaluated by calculating the tumor growth inhibition value. NDGA substantially inhibited the growth of human breast carcinoma cells in both animal and cell-based models. We also found that a single treatment with NDGA reactivates methylation-silenced E-cadherin gene in vitro and in vivo, suggesting an intriguing concept that lignans may act as natural effective epigenetic modifiers in the prevention and treatment of cancer.
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PMID:Nordihydroguaiaretic acid restores expression of silenced E-cadherin gene in human breast cancer cell lines and xenografts. 1841 15

Combination therapy with multiple drugs is a common practice in the treatment of cancer. The promising clinical activity of docetaxel has promoted considerable interest in combining it with other antitumor agents. To determine whether cucurbitacin B can enhance chemosensitivity to docetaxel in laryngeal cancer, in the present study, we investigated the combined antitumor effect of cucurbitacin B with docetaxel on Hep-2, a human laryngeal cancer cell line. We treated Hep-2 cells with cucurbitacin B alone or in combination with docetaxel and evaluated cell growth, cell cycle distribution, and apoptosis using MTT (3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide) assay, flow cytometry, and fluorescent microscopy. Our results showed that, in comparison with single agent treatment, the combination of cucurbitacin B and docetaxel produced greater efficacy in growth inhibition, cell cycle arrest at G2/M phase, and apoptosis induction. Measuring the modulation of regulators in the cell cycle, apoptosis and signal transductions by Western blot analysis showed that the combination effect of cucurbitacin B and docetaxel was due to suppress the expression of p-STAT3 (signal transducers and activators of transcription 3), Bcl-2, and cyclin B1. Moreover, our in vivo studies were reproduced in a mouse xenograft model, where, the combination of cucurbitacin B with docetaxel synergestively inhibited tumor growth. Together, this investigation suggests that cucurbitacin B combined with docetaxel may be a feasible strategy to enhance the effects of chemotherapy in patients with laryngeal cancer.
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PMID:Combined antitumor activity of cucurbitacin B and docetaxel in laryngeal cancer. 1844 12

The oncogenic isoform of the p63 protein, delta Np63 (delta Np63), plays an important role in the pathogenesis of many epithelial carcinomas, and emerging evidences suggest that delta Np63 is a promising drug target. However, the functions of delta Np63 in transitional cell carcinoma of bladder (TCCB) are poorly defined. In this study, a delta Np63 shRNA expression vector was transfected into TCCB cell line 5637 and cell cycling, cell proliferation and protein expression were assessed by flow cytometry and 3-(4, 5-Dimethylthiazol-2-yl)-2, 5-dimethyl tetrazolium bromide (MTT) assay, and immunohistochemistry, respectively. The delta Np63 shRNA expression vector was also injected into 5637 cell xenograft tumors in nude mice, and tumor size was measured, tumor tissue morphology was assessed by immunohistopathology and transmission electron microscopy. In the in vitro study, delta Np63 shRNA transfection caused successful delta Np63 gene silencing and resulted in significant arrest of cell cycling and cellular proliferation (p<0.05) as well as cyclin D1 expression. In the nude mouse xenograft model, delta Np63 shRNA greatly inhibited tumor growth, induced tumor cell apoptosis (p<0.05) and resulted in cyclin D1 downregulation. Our data suggest that delta Np63 may play an oncogenic role in TCCB progression through promoting cell survival and proliferation. Intratumoral administration of delta Np63-specific shRNA suppressed tumor delta Np63 expression and cellular proliferation while promoted tumor cellular apoptosis, and therefore inhibited tumor growth and improved survival of xenograft-bearing mice, which was not accompanied by significant signs of systemic toxicity.
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PMID:Impaired delta NP63 expression is associated with poor tumor development in transitional cell carcinoma of the bladder. 1895 89

The Ras/Raf/MEK pathway represents an important oncogenic signaling pathway in gastrointestinal malignancies, including pancreatic cancer. Although activating B-Raf mutations are infrequent in pancreatic cancer, we hypothesized that targeting Raf could be valuable for therapy of this cancer entity. Moreover, as vascular endothelial growth factor receptor 2 (VEGFR2) is involved in tumor angiogenesis, we sought to investigate the effects of dual inhibition of Raf and VEGFR2 on pancreatic tumor growth, vascularization, and metastasis. Effects of a Raf/VEGFR2 inhibitor (NVP-AAL881) on pancreatic cancer cells, endothelial cells, and vascular smooth muscle cells were determined by Western blotting, 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide analysis, and migration assays, respectively. Changes in the expression of VEGF-A or survivin were investigated by ELISA and/or real-time PCR. The growth-inhibitory effects of Raf/VEGFR2 inhibition were additionally evaluated in orthotopic tumor models. Results showed that various Raf isoforms were activated in pancreatic cancer cells and NVP-AAL881 diminished the activation of MEK, Akt, Erk, and also STAT3. Moreover, dual inhibition of Raf/VEGFR2 significantly reduced VEGF expression and impaired cancer cell migration. Importantly, besides blocking VEGF-induced Erk and SAPK phosphorylation in endothelial cells, the Raf inhibitor diminished STAT3 phosphorylation, independent of a VEGFR2 blockade, and reduced the expression of survivin. In addition, cell proliferation and migration of both endothelial cells and vascular smooth muscle cells were significantly reduced. In vivo, blocking Raf/VEGFR2 significantly inhibited orthotopic tumor growth and vascularization and reduced cancer metastasis. In conclusion, blocking Raf exerts growth-inhibitory effects on pancreatic tumor cells, endothelial cells, and pericytes and elicits antiangiogenic properties. Dual targeting of Raf and VEGFR2 appears to be a valid strategy for therapy of pancreatic cancer.
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PMID:Dual targeting of Raf and VEGF receptor 2 reduces growth and metastasis of pancreatic cancer through direct effects on tumor cells, endothelial cells, and pericytes. 1900 34

INSM1 is a zinc finger transcription factor that plays an important role in pancreatic beta-cell development. To further evaluate its role in cell fate determination, we investigated INSM1 effects on cell cycle function. The cyclin box of cyclin D1 is essential for INSM1 binding. Competitive pull-down and co-immunoprecipitation revealed that INSM1 binding to cyclin D1 interrupts its association with CDK4 and induces hypophosphorylation of the retinoblastoma protein. An inducible Tet-on system was established in Cos-7 and Panc-1 cells. Using serum starvation, we synchronized the cell cycle and subsequently induced cell cycle progression by serum stimulation. Comparison of the INSM1 induction group with the noninduced control group, INSM1 ectopic expression causes cell cycle arrest, whereas the INSM1-mediated cell cycle arrest could be reversed by cyclin D1 and CDK4 overexpression. The proline-rich N-terminal portion of INSM1 is required for cyclin D1 binding. Mutation of proline residues abolished cyclin D1 binding and also diminished its ability to induce cell cycle arrest. Cellular proliferation of Panc-1 cells was inhibited by INSM1 overexpression demonstrated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, soft agar colony formation, as well as tumor growth in a nude mouse model. Taken together, we provide evidence to support that INSM1 binds to cyclin D1, interrupts cell cycle signaling, and inhibits cellular proliferation.
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PMID:Zinc finger transcription factor INSM1 interrupts cyclin D1 and CDK4 binding and induces cell cycle arrest. 1912 61


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