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Query: UMLS:C0242379 (lung cancer)
 71,905 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Retinoic acid has been shown to be an anticancer agent, and a growing literature suggests that it is the nuclear retinoic acid receptor beta2 (RARbeta2) that is primarily responsible for mediating this effect, at least in some systems. To determine whether partial inactivation of RARbeta2 would predispose to lung cancer in mice, we generated three transgenic lines expressing antisense sequences. When killed at 13-3/4-18 months of age, 21/36 animals had a total of 43 pulmonary tumors superficially visible upon necropsy, whereas among 23 nontransgenic mice, only 1 had a single visible lung tumor. A twofold higher incidence of lung tumors was seen in homozygous vs. hemizygous antisense mice. The endogenous RARbeta2 message level was reduced in transgenic lung tissue and further reduced in the tumors. RARbeta4, a truncated isoform derived from the same transcript as RARbeta2, does not carry the sequence identified by the antisense construct and its message was not as strongly affected. Immunofluorescence studies showed that RARbeta was virtually undetectable in the tumors, but present in normal tissue. We conclude that RARbeta2, but probably not RARbeta4, plays an important role in suppression of murine lung tumorigenesis.
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PMID:Lung tumors in mice expressing an antisense RARbeta2 transgene. 880 Nov 72

The toxicity and marginal effectiveness of cytotoxic chemotherapy in metastatic non-small cell lung cancer (NSCLC) necessitates the search for new agents. Preliminary data in lung cancer and other malignant and premalignant disorders have identified retinoid compounds as potentially useful antitumor agents. Twenty-eight patients with metastatic NSCLC were treated with oral all-trans retinoic acid in a phase II trial. The study population consisted of patients with excellent performance status and minimal weight loss. Toxicities were generally mild and included cutaneous effects, headache, and myalgia. A significant number of patients developed elevations of hepatic transaminases or hyperlipidemia and 3 patients had treatment-related leukocytosis. Two patients (8%) achieved a partial response, and 1 had a mixed response. The duration of remission in the 2 responders was 7 and 13 months and the median survival of all patients 7 months. Therefore, all-trans retinoic acid has minimal activity as a single agent in NSCLC but warrants further study in combination with biological agents and chemotherapy.
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PMID:Phase II trial of all-trans retinoic acid in metastatic non-small cell lung cancer. 881 56

Retinoids show promise for prevention and treatment of cancers. In most cases, the mechanisms of their anticancer effects are poorly defined, but interactions with cytokine genes have been postulated in several systems. The effects of trans-retinoic acid (RA) on proliferation and cytokine gene expression in the human lung carcinoma Lu-CSF-1 are reported. RA exhibited cell-cycle independent inhibition of Lu-CSF-1 growth while stimulating endogenous interleukin-1 beta and suppressing granulocyte-macrophage colony-stimulating factor and IL-6 mRNAs. Reduction in granulocyte-macrophage colony-stimulating factor and IL-6 message was associated with reduced RNA stability and was translated into reduced protein levels. IL-1 beta mRNA stability was not decreased, and elevation in IL-1 beta protein levels was of a comparable magnitude to the increased amounts of its RNA. Growth inhibition similar to that following RA treatment could be reproduced by exposing cells to exogeneous IL-1 beta alone. These data suggest that changes in autologous cytokine gene expression might contribute to growth inhibition of lung cancer cells by RA.
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PMID:The antiproliferative effect of trans-retinoic acid is associated with selective induction of interleukin-1 beta, a cytokine that directly inhibits growth of lung cancer cells. 886 67

The secosteroid 1 alpha, 25-dihydroxyvitamin D3 (calcitriol) and retinoic acid are the major biologically active metabolites of vitamins D and A, respectively. Their antitumor activity has been observed in several cancer cells in vitro apart from lung cancer cells. The purpose of this study was to examine the possible effects of the agents on lung cancer cell lines. The responses of five lung cancer cell lines to calcitriol or all-transretinoic acid (RA) were assessed by a colorimetric MTT assay. Calcitriol inhibited growth in one of the tested cell lines, i.e. EBC-1 squamous cell carcinoma, dose dependently. RA also exhibited the same effect in EBC-1 cells. However neither agent affected the growth of other lung cancer cell lines. Subsequently we examined the mRNA expression of vitamin D receptor (VDR) and retinoic acid receptor (RAR alpha) in these lung cancer cells by quantitative RT-PCR. EBC-1 cells expressed high levels of mRNA for both VDR and RAR alpha, while other cell lines expressed much lower mRNA levels for the receptors. These data suggest that the growth inhibitory effects of the vitamins are associated with mRNA expression for VDR and RAR alpha.
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PMID:1 alpha, 25-dihydroxyvitamin D3 and all-trans-retinoic acid inhibit the growth of a lung cancer cell line. 891 65

The nm23 and mts1 genes have been the focus of attention as regards the association of their expression with metastatic behaviour. The level of nm23 and mts1 gene products has been demonstrated to correlate with metastatic potential in some tumors, but not in all. Here we show that these two genes might be coregulated and the ratio of their expression correlated with metastatic behaviour. Western blot analysis showed that the expression of both NM23 and MTS1 proteins was reduced in human lung cancer CH27 cells by retinoic acid treatment, but the ratio of NM23: MTS1 increased in a dose-dependent manner. Results also exhibited that retinoic acid altered the microtubule assembly of CH27 cells and reduced the metastatic ability of the cells in vitro. These data suggest that the metastatic potential of CH27 cells may be related to the relative expression of these two genes, and that their pathway in regulating metastatsis might be linked.
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PMID:Increased NM23: MTS1 ratio inversely correlated with metastasis behaviour in human lung squamous cell carcinoma. 906 85

Comparison of the adherent growth inhibition of NIH:OVCAR-3 ovarian cancer cells by retinoid receptor class-selective and subtype-selective compounds with their receptor binding affinities and transcriptional activation activities indicated no correlation for RAR alpha and RAR gamma although both receptors are present. Retinoids that activated RXR alpha inhibited cell growth in the range as all-trans-retinoic acid and 9-cis-retinoic acid. The most potent inhibitor was 6-[3-(1-adamantyl)-4-hydroxyphenyl]-2-naphthalenecarboxylic acid (AHPN), which has been found to inhibit breast and lung cancer and leukemia cell growth and induce cancer cell apoptosis through a pathway independent of the retinoid receptors.
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PMID:Effects of receptor class- and subtype-selective retinoids and an apoptosis-inducing retinoid on the adherent growth of the NIH:OVCAR-3 ovarian cancer cell line in culture. 909 72

The diverse function of retinoic acid (RA) is mediated by its nuclear receptors, the retinoic acid receptors (RARs) and retinoid X receptors (RXRs). However, the RA response is often lost in cancer cells that express the receptors. Previously, it was demonstrated that the RA response is regulated by the COUP-TF orphan receptors. Here, we present evidence that nur77, another orphan receptor whose expression is highly induced by phorbol esters and growth factors, is involved in modulation of the RA response. Expression of nur77 enhances ligand-independent transactivation of RA response elements (RAREs) and desensitizes their RA responsiveness. Conversely, expression of COUP-TF sensitizes RA responsiveness of RAREs by repressing their basal transactivation activity. Unlike the effect of COUP-TFs, the function of nur77 does not require direct binding of nur77 to the RAREs, but is through interaction between nur77 and COUP-TFs. The interaction occurs in solution and results in inhibition of COUP-TF RARE binding and transcriptional activity. Unlike other nuclear receptors, a large portion of the carboxy-terminal end of nur77 is not required for its interaction with COUP-TF. In human lung cancer cell lines, COUP-TF is highly expressed in RA-sensitive cell lines while nur77 expression is associated with RA resistance. Stable expression of COUP-TF in nur77-positive, RA-resistant lung cancer cells enhances the inducibility of RARbeta gene expression and growth inhibition by RA. These observations demonstrate that a dynamic equilibrium between orphan receptors nur77 and COUP-TF, through their heterodimerization that regulates COUP-TF RARE binding, is critical for RA responsiveness of human lung cancer cells.
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PMID:Modulation of retinoic acid sensitivity in lung cancer cells through dynamic balance of orphan receptors nur77 and COUP-TF and their heterodimerization. 913 Jul 11

Lung cancer causes more than 140,000 deaths annually in the United States alone, and the prognosis for non-small cell lung cancer (NSCLC) is particularly poor. Therapies using small molecules that preferentially kill lung tumor cells by inducing cellular suicide (apoptosis) would therefore be highly desirable. Retinoids have shown promise as cancer preventive and cancer therapeutic agents. Retinoid signals are mediated by two classes of nuclear receptors: the retinoic acid receptors (RAR alpha, beta, and gamma) and the retinoid X receptors (RXR alpha, beta and gamma). These receptors usually bind as heterodimers to specific DNA sequences and/or interact with other transcriptional regulators, such as AP-1 (ref. 10) to regulate gene transcription. Synthetic retinoids can be made that activate only specific portions of the complex retinoid response network and activate selective biological programs. To identify retinoids with novel biological activities, we used a high-throughput "biological activity fingerprint" screen on a large library of retinoids and retinoid-related molecules (RRMs). We identified new structures that are highly effective against lung cancer cells in vitro, inducing apoptosis. We show here for one of these compounds that it is very effective against a human NSCLC in vivo in an animal model. These new molecules show a distinct pattern of receptor signaling.
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PMID:Novel retinoid-related molecules as apoptosis inducers and effective inhibitors of human lung cancer cells in vivo. 917 99

Because adjuvant chemotherapy has resulted in only modest prolongation of survival for patients with lung cancer, investigators have turned to the evaluation of alternative treatment strategies for this patient population. Immunotherapy with Bacillus Calmette Guerin, Corynebacterium parvum, and levamisole has been evaluated in several prospective randomized trials, and no study has shown a statistically significant difference in overall survival. Interferon has been evaluated in three trials of adjuvant therapy after response to chemotherapy for small cell lung cancer. Different interferon preparations were used, but none of the trials showed a significant prolongation of survival. The retinoids have been evaluated as adjuvant treatment after complete resection of stage IN-SCLC. One trial showed a reduction in second primary tumors, and in particular, tumors to tobacco smoking in patients treated with retinyl palmitate. A second trial using 13-cis retinoic acid is ongoing in North America. In the last decade, several inhibitors of angiogenesis have been identified, and they are now beginning to be evaluated in the clinical setting. The National Cancer Institute of Canada Clinical Trials Group and the European Organization for Research and Treatment of Cancer have initiated a study of adjuvant marimastat, a metalloproteinase inhibitor, for patients who have responded to induction chemotherapy for small cell lung cancer. This is the first adjuvant antiangiogenesis factor trial to be initiated for any tumor type. Other investigational agents which are currently undergoing Phase I and Phase II testing include monoclonal antibodies which may inhibit tumour cell growth by binding to growth factors, or which may be conjugated to toxins or chemotherapeutic agents which result in tumour cell death. In the last decade, we have witnessed an explosion in our knowledge and understanding of the regulation of normal and neoplastic cell growth at the molecular level. It remains only speculative at this time as to whether manipulation of abnormal genes in malignant cells will be clinically possible, and whether treatment of this sort may be applied in an adjuvant setting.
Lung Cancer 1997 Jun
PMID:Alternatives to chemotherapy and radiotherapy as adjuvant treatment for lung cancer. 921 9

Vitamin A analogs (retinoids) suppress oral and lung carcinogenesis in animal models and prevent the development of second primary tumors in head, neck, and lung cancer patients. These effects result from changes in the expression of genes that regulate cell growth and differentiation. Retinoic acid receptors (RARs; -alpha, -beta, and -gamma) and retinoid X receptors (RXRs; -alpha, -beta, and, -gamma) are retinoid-activated transcription factors, which mediate effects of retinoids on gene expression. Therefore, alterations in receptor expression or function could interfere with the retinoid signaling pathway and thereby enhance cancer development. We found that the expression of RAR beta was suppressed in more than 50% of oral and lung premalignant lesions in individuals without cancer and in dysplastic lesions adjacent to cancer and in malignant oral and lung carcinomas. The expression of the other receptors was not different among normal, dysplastic, and malignant oral tissues. However, the expression of RAR gamma and RXR beta was somewhat decreased in lung cancers. These results show that RAR beta expression is lost at early stages of carcinogenesis in the aerodigestive tract and support the hypothesis that the loss of RAR beta expression may facilitate the development of some of these cancers.
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PMID:Roles of retinoids and their nuclear receptors in the development and prevention of upper aerodigestive tract cancers. 925 92


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