Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027651 (tumor)
 685,946 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

We have constructed a replication-deficient adenovirus encoding a nonphosphorylatable Thr(34)-->Ala mutant of the apoptosis inhibitor survivin (pAd-T34A) to target tumor cell viability in vitro and in vivo. Infection with pAd-T34A caused spontaneous apoptosis in cell lines of breast, cervical, prostate, lung, and colorectal cancer. In contrast, pAd-T34A did not affect cell viability of proliferating normal human cells, including fibroblasts, endothelium, or smooth muscle cells. Infection of tumor cells with pAd-T34A resulted in cytochrome c release from mitochondria, cleavage of approximately 46-kDa upstream caspase-9, processing of caspase-3 to the active subunits of approximately 17 and 19 kDa, and increased caspase-3 catalytic activity. When compared with chemotherapeutic regimens, pAd-T34A was as effective as taxol and considerably more effective than adriamycin in induction of tumor cell apoptosis and enhanced taxol-induced cell death. In three xenograft breast cancer models in immunodeficient mice, pAd-T34A suppressed de novo tumor formation, inhibited by approximately 40% the growth of established tumors, and reduced intraperitoneal tumor dissemination. Tumors injected with pAd-T34A exhibited loss of proliferating cells and massive apoptosis by in situ internucleosomal DNA fragmentation. These data suggest that adenoviral targeting of the survivin pathway may provide a novel approach for selective cancer gene therapy.
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PMID:Cancer gene therapy using a survivin mutant adenovirus. 1180 41

Survivin inhibits apoptosis during development and carcinogenesis and is absent in differentiated cells. To determine whether survivin inhibition induces cell death in neural tumor cells, survivin antisense oligonucleotides (SAO) were administered to a human neuroblastoma (MSN) and an oligodendroglioma (TC620) resulting in a dose-dependent reduction in survivin protein. Although 74% of the SAO-treated MSN cells were trypan blue(+), PARP cleavage or activated caspase-3 was not observed. However nuclear translocation of AIF occurred and XIAP increased dramatically. Co-administration of z-Val-Ala-Asp(OMe)-fluoromethyl ketone (zVAD-fmk) with SAO did not inhibit cell death suggesting a caspase-independent mechanism of cell death. Propidium iodide (PI) staining revealed multiple large macronuclei with no apoptotic bodies supporting a role for survivin in cell division. By contrast, while 70% of the SAO-treated TC620 cells were trypan blue(+), PARP was cleaved, cells were TUNEL(+) and PI-staining revealed macronuclei and numerous apoptotic bodies. Co-treatment of the TC620 cells with SAO and zVAD-fmk blocked cell death. While no macronuclei or apoptotic bodies were observed there was a two-fold increase in metaphase cells. Our results suggest that survivin inhibition decreases the viability of human neural tumor cells and as a result of mitotic catastrophe, cell death can be initiated by either a classic apoptotic mechanism or a caspase-independent mechanism.
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PMID:Survivin inhibition induces human neural tumor cell death through caspase-independent and -dependent pathways. 1167 71

Survivin is a member of the inhibitor of apoptosis protein (IAP) family. The expression of survivin has not been reported in differentiated normal tissues, but it has been observed in many cancerous tissues. Recent studies have revealed that survivin may correlate with the chemo-radio resistance of certain malignant cells. In the present study, the correlation between the occurrence of apoptosis and the level of expression of survivin messenger RNA (mRNA) was investigated in a gastric cancer cell line (MKN-45) and in patients with advanced gastric cancer during cisplatin (CDDP) treatment. In the gastric cancer cell line, the percentage of apoptotic cells (apoptotic index: AI) did not change after 48 h incubation with low-dose CDDP (1 microg/ml), whereas the AI explosively increased between 12 and 24 h treatment with high-dose CDDP (10 microg/ml). Relative levels of expression of survivin mRNA and survivin protein increased after low- and high-dose CDDP treatment. Survivin mRNA was not detected in normal gastric mucosas. Also, in 13 patients with advanced gastric cancer who underwent CDDP-based preoperative chemotherapy, survivin mRNA was detected in only 2 cases (15.4%). Survivin mRNA was observed in the resected tumor specimens of two cases. No significant correlation between survivin mRNA expression and the occurrence of apoptosis in resected tumors or between survivin mRNA expression and patient survival was observed. These findings indicate that survivin may play an important role for the chemoresistance of this cancer cell line. However, the clinical importance of survivin expression remains unclear in patients with gastric cancer.
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PMID:Changes in survivin messenger RNA level during cisplatin treatment in gastric cancer. 1171 83

The tumor necrosis factor (TNF) receptor family are ligand-regulated transmembrane proteins that mediate apoptosis as well as activation of the transcription factor NF-kappaB. Exogenous expression of DR6, a recently identified member of the TNF receptor family, induced apoptosis in untransformed or tumor-derived cells and the apoptotic function of DR6 was inhibited by co-expression of Bcl-2, Bcl-x(L) or the inhibitor-of-apoptosis (IAP) family member, survivin. Expression of a dominant negative mutant of FADD failed to protect from DR6-mediated apoptosis indicating that unlike TNFR1 and Fas, DR6 induced apoptosis via a FADD-independent mechanism. Despite the ability of exogenous DR6 expression to induce apoptosis, DR6 mRNA and protein were found to be elevated in prostate tumor cell lines and in advanced stages of prostate cancer. Analysis of several anti-apoptotic proteins revealed that Bcl-x(L) levels and serine 32 phosphorylation of IkappaB, the natural inhibitor of NF-kappaB, were similarly elevated in cells expressing high levels of DR6, suggesting that NF-kappaB-regulated survival proteins may protect from DR6-induced apoptosis and that DR6 is a target of NF-kappaB regulation. Treatment of LnCAP cells with TNF-alpha resulted in increases in both DR6 mRNA and protein levels, and this induction was suppressed by inhibitors of NF-kappaB. Similarly, treatment of cells expressing high levels of DR6 with indomethacin and ibuprofen, compounds also known to perturb NF-kappaB function, resulted in a dose-dependent decrease in DR6 protein and mRNA levels. These results demonstrate that TNF-alpha signaling induces the expression of a member of its own receptor family through activation of NF-kappaB.
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PMID:Tumor necrosis factor-alpha induces the expression of DR6, a member of the TNF receptor family, through activation of NF-kappaB. 1175 79

Bryostatin 1 (bryo 1) has been shown to potentiate the anti-tumor activity of 2-chloro-2-deoxyadenosine (2-CdA) in chronic lymphocytic leukemia (CLL) and in the WSU-CLL cell line. However, like resistant CLL, WSU-CLL cells lose their sensitivity to bryo 1/2-CdA treatment. We report that 2-CdA-induced IAP expression may be a possible mechanism whereby resistance to apoptosis is acquired in these cells. In WSU-CLL cells, three members of the Inhibitors of Apoptosis (IAP) family were identified. Bryo 1 treatment of WSU-CLL cells leads to initiation of the apoptotic cascade and induced a marginal increase in XIAP protein expression. In contrast, 2-CdA treatment, alone or in combination with bryo 1, induced a substantial increase in survivin and XIAP proteins and phosphorylation of BAD. Bryo 1 alone induced caspase-7 and -9 dependent [poly ADP-ribose] polymerase (PARP) cleavage, while sequential treatment with bryo 1 (72 h) followed by 2-CdA (24 h) induced caspase-3,-7, and -9 dependent PARP cleavage and increased apoptosis. Although exposure to bryo 1 initiated apoptotic events, apoptosis was first enhanced by 2-CdA, and then reversed in a time-dependent manner by 2-CdA-induced expression of survival proteins. Taken together, resistance to bryo 1/2-CdA treatment may be the result of 2-CdA-induced IAP inhibition of the intrinsic apoptotic pathway caspases.
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PMID:Treatment-induced expression of anti-apoptotic proteins in WSU-CLL, a human chronic lymphocytic leukemia cell line. 1177 Jul 3

The current "gold standard" for the diagnosis of bladder cancer is cystoscopy and urine cytology. Cystoscopy, a naked eye assessment of the bladder, is invasive, uncomfortable and costly while cytology has high specificity but low sensitivity (40-60%) particularly for low-grade lesions. Therefore, there is a need for a molecular tumor marker assay that is simple to perform and sensitive, particularly for low-grade lesions. By looking to the pathophysiology of bladder cancer, we identified survivin, an inhibitor of apoptosis that is not generally expressed in fully differentiated adult tissue and is highly expressed in bladder cancer. Survivin is detected in whole urine of patients with TCC using a simple antibody based test. The sensitivity of survivin testing for new or recurrent bladder cancer is 100% while the specificity for other neoplastic and non-neoplastic genitourinary disease is 95%. The high sensitivity of this simple, noninvasive test is well suited to bladder cancer, a disease with high rates of recurrence.
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PMID:Bladder cancer detection with urinary survivin, an inhibitor of apoptosis. 1181

The recently discovered 16.5 kDa protein survivin was found to inhibit the two early apoptotic enzymes caspase-3 and caspase-7, thus preventing programmed cell death. Survivin may act simultaneously with the bel-2 family proteins, but has a different apoptosis inhibitory mechanism. Numerous reports have demonstrated the expression of survivin in various tumors such as neuroblastoma, melanoma, bladder carcinoma, breast and lung non-small cell tumors, esophegeal and colo-rectal carcinomas and leukemic cells. In contrast, this protein was not traced in adjacent normal tissues by either immunohistochemical staining or by PCR analysis of the expression of survivin mRNA. Importantly, there seems to be a positive correlation between survivin expression and tumor grading, as well as an indication of tumor recurrence after resection or chemotherapy. Potentially, this protein could add to the repertory of diagnostic and prognostic markers in monitoring oncologic patients.
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PMID:[Survivin: anti-apoptosis protein and a prognostic marker for tumor progression and recurrence]. 1185 Oct 94

Suppression of apoptosis is important for carcinogenesis and tumor growth. Recent studies revealed that survivin not only inhibited apoptosis but also accelerated cancer cell proliferative activity. To investigate the prognostic role of expression of the antiapoptosis gene, survivin, in hepatocellular carcinoma (HCC), the authors analyzed the correlation between the expression pattern of survivin messenger RNA (mRNA) and clinicopathologic findings of patients. Tissues were obtained by surgical resection of livers from 51 patients with HCC and 6 patients without HCC. Expression of survivin mRNA was evaluated using reverse transcription-polymerase chain reaction in 51 tumors, 51 adjacent histologically noncancerous livers, and 6 normal livers. Survivin protein expression was evaluated using Western blotting, and apoptotic cancer cells were detected by immunostaining with polyclonal rabbit anti-single-stranded DNA. Survivin mRNA expression was detected in 21 of 51 (41%) tumors, 2 of 51 (4%) noncancerous livers, and none of the 6 normal livers. Survivin mRNA expression did not correlate with tumor size or stage of HCC. Percentage of apoptotic cancer cells of 30 survivin mRNA-negative tumors (5.2 +/- 3.4%) was significantly higher than that of 21 survivin mRNA-positive tumors (2.2 +/- 2.3%, P = 0.0019). The disease-free 5-year survival rate of 21 patients positive for survivin mRNA (19%) was significantly poorer than that of 30 patients negative for survivin mRNA (39%, P = 0.0148). Survivin mRNA was detected in 57% (17/30) patients with HCC recurrence but in only 19% (4/21) of patients without recurrence (P = 0.0072). These results indicated that survivin mRNA expression could be used as an independent prognostic factor for patients with HCC after hepatectomy.
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PMID:Expression of survivin messenger RNA correlates with poor prognosis in patients with hepatocellular carcinoma. 1185

We studied the human HL60 leukemia cell line and its multidrug resistant (MDR) variant HL60R. In contrast to the HL60, HL60R showed an inability to undergo apoptosis from doxorubicin (Dox) or other different stimuli, including cisplatin, Fas ligation and serum withdrawal. HL60R cells lost surface Fas expression, but we found no evidence that Fas/FasL mediates the apoptotic effects of Dox in HL60. P-glycoprotein (P-gp) did not seem to play a major role as a specific inhibitor of apoptosis. In fact, the P-gp inhibitor verapamil reversed only partially the resistance to Dox-induced apoptosis of the MDR cells. In addition, it did not modify the rate of apoptosis induced from the other stimuli in the same cells. The expression of p53 or Bcl-2 was not different between HL60 and HL60R. However, in HL60R there was an increase in the mRNAs of inhibitory of apoptosis proteins (IAPs) like neuronal apoptosis inhibitory protein (NAIP), c-IAP-2 and survivin. Treatment with Dox or serum starvation strongly down-regulated X-linked IAP and survivin mRNAs in HL60. Cisplatin decreased NAIP and survivin mRNAs in the same cells. However, in HL60R the levels of these IAP mRNAs were much less affected by the treatments. These results support that IAPs may be involved in tumor resistance to chemotherapeutic drugs or other apoptotic agents.
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PMID:Resistance to diverse apoptotic triggers in multidrug resistant HL60 cells and its possible relationship to the expression of P-glycoprotein, Fas and of the novel anti-apoptosis factors IAP (inhibitory of apoptosis proteins). 1191 75

Although standard anticancer chemotherapeutic drugs have been designed to inhibit the survival or growth of rapidly dividing tumor cells, it is possible to enhance the efficacy of such drugs by targeting the proliferating host endothelial cells (ECs) of the tumor vasculature. A theoretical advantage of this strategy lies in the possibility of circumventing, or significantly delaying, acquired drug resistance driven by the genetic instability of tumor cells. Here, we show that both vascular endothelial growth factor (VEGF) and basic fibroblast growth factor significantly reduce the pro-apoptotic potency of chemotherapy on both micro- and macrovascular ECs. This cytoprotection to drug toxicity was found to be phosphatidylinositol 3-kinase-dependent and could be recapitulated in the absence of VEGF by overexpressing the dominant-active form of the serine/threonine kinase protein kinase B/Akt. Downstream of phosphatidylinositol 3-kinase, we also show that survivin plays a pivotal role in VEGF-mediated EC protection by preserving the microtubule network. In this respect, its induction effectively protects ECs against chemotherapeutic damage, whereas overexpression of its dominant-interfering mutant (C84A) abrogates the protective effects of VEGF. Accordingly, the potency of VEGF as a chemoprotectant was more pronounced with drugs that interfere with microtubule dynamics than those that damage DNA. These studies implicate a role for survivin up-regulation as a novel mechanism of EC drug "resistance" and support the notion that angiogenic factors that induce the expression of survivin may act to shield tumor ECs from the apoptotic effects of chemotherapy. Thus, exploiting chemotherapeutic drugs as antiangiogenics is likely to be compromised by the high concentrations of proangiogenic survival/growth factors present in the tumor microenvironment; targeting EC survival pathways should improve the antiangiogenic efficacy of antineoplastic agents, particularly microtubule-inhibitor drugs.
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PMID:A role for survivin in chemoresistance of endothelial cells mediated by VEGF. 1191 34


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