Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0699790 (colon cancer)
 28,837 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The aim of this study was to survey the expression of an embryonic cytokine gene, MK, in the normal organs and neoplastic tissues of adults. Northern analysis showed that MK mRNA was exclusively expressed in the kidney among murine organs including thymus, lung, heart, spleen, liver, and kidney. In situ hybridization analysis revealed that MK expression was localized in the proximal tubules and metaplastic Bowman's epithelium, but not in other nephron segments such as glomeruli, loop of Henle, distal tubules, and collecting ducts. To investigate whether MK expression is a marker of tubular cell lineage, several cell lines originating from renal tubules were tested. No expression of MK was detected in PtK1 and LLC-PK1 cells derived from marsupial and porcine proximal tubules or in MDBK and MDCK cells from bovine and canine distal/collecting tubules. Unexpectedly, the MK gene was expressed in a human renal cell carcinoma line, VMRC-RCW, and the expression was up-regulated in the presence of retinoic acid. To elucidate the involvement of MK in the development of tumors, we further examined its expression in a variety of human neoplastic cell lines: YMB-1-C (breast cancer), EBC-1 (lung squamous cell carcinoma), RERF-LC-OK (lung adenocarcinoma), SBC-3 (lung small cell carcinoma), HSC-2 (mouth squamous cell carcinoma), NUGC-2 (gastric cancer), COLO201 (colon cancer), HepG2 (hepatoma), MIA PaCa-2 (pancreatic cancer), MCAS (ovarian cancer), HeLa (cervical cancer), BeWo (chorionic carcinoma), ITO-II (testicular tumor), T24 (urinary bladder tumor), and G-401 (Wilms' tumor). Strong signals were detected in COLO201, HepG2, ITO-II, T24, G-401, and weaker but distinct signals were detected in YMB-1-C, HSC-2, and MCAS cells. The MK gene was, therefore, widely expressed in neoplastic cells originating from genital organs, intestinal tract, liver, mammary gland, and urinary tract, and the expression was not restricted to adenocarcinomas, but was also observed in other types of tumor cells. These findings suggest that a retinoic acid responsive gene, MK, may play a role in the pathophysiology of renal proximal tubules and tumorigenesis in many types of neoplasms.
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PMID:A retinoid responsive cytokine gene, MK, is preferentially expressed in the proximal tubules of the kidney and human tumor cell lines. 843 39

Radiolabeled monoclonal antibodies have been used for radioimmunotherapy studies with human tumor spheroids and murine and human tumor xenografts in experimental animals. This paper reviews the work that has been performed in these models with different types of cancer, and highlights those papers that have presented dosimetry estimates and attempts to correlate the findings. Radioimmunotherapy studies in multicell spheroids, as a model for micrometastases, have been performed in human neuroblastoma, colon cancer, and melanoma cell lines using 131I-, 125I-, 186Re-, and 212Bi-labeled antibodies. The uniform geometry of the spheroid has allowed radiation dose estimates to be made. Up to three logs of cell kill have been achieved with 131I- and 186Re-specific antibody with minimal toxicity from labeled nonspecific antibody, but 212Bi-antibody had little effect because of its short half-life as shown by Langmuir. It appears that the two most important factors for therapeutic efficacy in this model are good penetration of the radiolabeled antibody and an adequate radionuclide half-life to allow penetration of the immunoconjugate prior to significant radionuclide decay. Radioimmunotherapy studies in animals bearing transplants of colon cancer, leukemia, lymphoma, hepatoma, renal cell carcinoma, neuroblastoma, glioma, mammary carcinoma, small cell lung carcinoma, cervical carcinoma, ovarian carcinoma, and bladder cancer have been performed with 131I, 90Y, 186Re, 153Sm, and 177Lu beta emitting, and 212Bi alpha emitting radionuclides conjugated to monoclonal antibodies. A few studies compared different radionuclides in the same model system. The approaches that have been used in these studies to estimate tumor dosimetry include the MIRD approach, thermoluminescent dosimetry, autoradiography, and comparison to external irradiation. The majority of investigators have estimated the dose to tumor and normal organs using MIRD-based calculations (time-activity curve and equilibrium dose constant method). The range of tumor doses has been between 17 and 11 171 mGy/MBq of administered radioactivity. The effectiveness of radiolabeled monoclonal antibody therapy depends on a number of factors relating to the antibody such as specificity, affinity, and immunoreactivity. The density, location, and heterogeneity of expression of tumor-associated antigen within tumors will affect the localization and therapeutic efficacy of radiolabeled antibodies, as will physiological factors such as the tumor vascularity, blood flow, and permeability. These factors are discussed and examples are presented.(ABSTRACT TRUNCATED AT 400 WORDS)
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PMID:Experimental radioimmunotherapy. 849 64

The advanced tumours of the digestive tract are generally less responsive to conventional chemotherapies. Moreover, preliminary results with IL-2 immunotherapy also seem to show a low efficacy. On the basis of our previous studies suggesting s synergistic action between IL-2 and some neurohormones, such as the pineal indole MLT, a clinical trial was performed to investigate the clinical efficacy and tolerability of an immunotherapy with IL-2 plus MLT in patients with advanced neoplasms of the digestive tract. The study included 35 patients (colorectal cancer: 14; gastric cancer: 8; hepatocarcinoma: 6; pancreas adenocarcinoma: 7). Distant organ metastases were present in 31/35 patients. MLT was given orally at a daily dose of 50 mg at 8.00 p.m., starting 7 days before IL-2, which was given subcutaneously at a dose of 3 million IU/day at 8.00 p.m. for 6 days/week for 4 weeks, corresponding to one cycle of immunotherapy. In nonprogressed patients, a second cycle was given after a 21-day rest period. A complete response was achieved in two patients (gastric cancer: 1; hepatocarcinoma: 1). Six other patients obtained a partial response: (gastric cancer: 2; hepatocarcinoma: 2; colon cancer: 1; pancreas cancer: 1). Therefore, the overall response rate was 8/35 (23%). Stable disease was obtained in 11/35 (31%) patients, whereas the remaining 16 patients (46%) progressed. The response rate was significantly higher in untreated patients than in those previously treated with chemotherapy. Toxicity was low in all patients, who received the treatment as a home therapy. This study shows that the immunotherapy with low-dose IL-2 plus the pineal hormone MLT is a new well tolerated and effective therapy of advanced tumours of the digestive tract, mainly in gastric cancer and hepatocarcinoma.
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PMID:Immunotherapy with subcutaneous low-dose interleukin-2 and the pineal indole melatonin as a new effective therapy in advanced cancers of the digestive tract. 851 25

In a consecutive series of 146 patients with hepatocellular carcinoma (HCC), 10 patients (6.8%) were found to have one or two extrahepatic malignancies (EHM). Of these, eight had double cancers and two, triple cancers. The associated malignancies included eight cases of gastric cancer and four cases of colon cancer. Among the 12 lesions, eight were in the early stage. All the 10 patients were hepatitis B surface antigen negative. The incidence of coexisting liver cirrhosis and the retention rate of indocyanin green in 15 minutes among HCCs with EHM were significantly lower than those among HCC alone. These results suggest that the etiology of HCC with EHM is different from the etiology of HCC alone in Japan.
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PMID:Clinical study on hepatocellular carcinoma with extrahepatic malignancies. 853 Feb 27

Attainment of cell type-specific cytotoxicity with minimal side effects is the ultimate goal of cancer therapy. By employing the prostate-specific antigen promoter (PSAP), we investigated (1) whether PSAP-driven antisense genetic constructs targeting DNA polymerase-alpha and topoisomerase II alpha (Top II alpha), designated PSAP-antipol and PSAP-antitop respectively, could induce death of prostate cancer cells, and (2) whether the cytotoxicity is restricted to cells of prostate origin. A PSAP-driven beta-galactosidase gene, PSAP-LacZ, was also used to estimate the expression of the PSAP-driven transcripts. Lipofection-mediated gene transfers were performed with these 3 constructs and a control plasmid, pCDNA3, in 3 human prostate cancer cell lines (LNCaP, DU-145, PC-3) and 5 other cell lines (Cos-1 [monkey kidney], HL-60 [human myeloid leukemia], Hep G2 [human hepatoma], NCI H460 [human lung cancer] and SW 480 [human colon cancer]). On transfection with PSAP-LacZ, LNCaP, DU-145, and PC-3 showed a 10.8, 1.8, and 1.6 fold increase in beta-galactosidase activity, respectively. The remaining 5 cell lines showed no changes after transfection. Corresponding to the levels of the induced beta-galactosidase activity, LNCaP showed the strongest growth inhibition by the antisense constructs: 36% by PSAP-antipol, 39% by PSAP-antitop and 80% by PSAP-antipol+PSAP-antitop. DU-145 and PC-3 had minimal growth inhibition with PSAP-antipol alone or PSAP-antitop alone. However, when cotransfected with PSAP-antipol and PSAP-antitop, DU-145 and PC-3 displayed 42% and 55% growth inhibition, respectively. In contrast, no cytotoxicity was observed in the remaining 5 cell lines when transfected with PSAP-antipol, PSAP-antitop or both. Therefore, PSAP-driven antisense gene therapy targeting DNA polymerase-alpha and Top II alpha inhibits the growth of human prostate cancer cells and the cytotoxic effect is restricted in cells of prostate origin.
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PMID:Prostate-specific antigen promoter driven gene therapy targeting DNA polymerase-alpha and topoisomerase II alpha in prostate cancer. 871 4

Curcumin, which is a widely used dietary pigment and spice, has been demonstrated to be an effective inhibitor of tumor promotion in mouse skin carcinogenesis. We report that curcumin induces cell shrinkage, chromatin condensation, and DNA fragmentation, characteristics of apoptosis, in immortalized mouse embryo fibroblast NIH 3T3 erb B2 oncogene-transformed NIH 3T3, mouse sarcoma S180, human colon cancer cell HT-29, human kidney cancer cell 293, and human hepatocellular carcinoma Hep G2 cells, but not in primary culture of mouse embryonic fibroblast C3H 10T1/2, rat embryonic fibroblast, and human foreskin fibroblast cells in a concentration- and time-dependent manner. Many cellular and biochemical effects of curcumin in mouse fibroblast cells have been reported, such as inhibition of protein kinase C (PKC) activity induced by phorbol 12-myristate 13-acetate treatment, inhibition of tyrosine protein kinase activity, and inhibition of arachidonic acid (AA) metabolism. Treatment of NIH 3T3 cells with the PKC inhibitor staurosporine, the tyrosine kinase inhibitor herbimycin A, and the AA metabolism inhibitor quinacrine induces apoptotic cell death. These results suggest that, in some immortalized and transformed cells, blocking the cellular signal transduction might trigger the induction of apoptosis.
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PMID:Curcumin induces apoptosis in immortalized NIH 3T3 and malignant cancer cell lines. 884 27

Concern for a risk of cancer in humans has been prompted by the appearance of hepatocellular carcinomas in tamoxifen-treated rats. However, there is no evidence of excess hepatocellular carcinoma among tamoxifen-treated women. Moreover, liver tumors are not induced in tamoxifen-treated mice or hamsters. An explanation for the species selectivity of this toxic effect may relate to the greater rate of formation of reactive intermediates in rats than either mice or humans. This results in persistent liver DNA adducts in tamoxifen-treated rat liver exceeding those produced in treated mice or in background levels measured in women taking tamoxifen. Another observation that reduces concern for human carcinogenesis is that bioactivation of tamoxifen may be inducible at dosages used in rodent cancer bioassays but not in those used clinically. Suggestions that endometrial cancer may be tamoxifen related are not supported by rodent data for endometrial cancer. Indeed, endometrial tissue lacks the necessary tamoxifen bioactivating capacity of liver consistent with the absence of DNA adducts in the endometrium of women taking tamoxifen. Finally, it seems doubtful that the colon is a target for human carcinogenesis of tamoxifen given the negative epidemiologic studies and high-dose rodent studies. In summary, there is at present no sound scientific basis for extrapolation of rat liver cancer findings to risks of liver, endometrial, and colon cancer in women receiving tamoxifen.
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PMID:Relevance of rat liver tumors to human hepatic and endometrial cancer. 904 9

ApolipoproteinB (apoB) mRNA editing involves a C to U deamination of the nuclear apoB mRNA and occurs in mammalian small intestine and in the liver of certain species. This reaction is mediated by a multicomponent enzyme complex that includes a catalytic subunit, apobec-1. Apobec-1 mRNA is widely expressed in the rat and mouse and is subject to tissue-specific regulation. In order to understand the basis for the species- and tissue-specific pattern of apobec-1 gene expression we have cloned and characterized the rat chromosomal apobec-1 gene. We demonstrate its structural organization and regulation in comparison to that of the mouse apobec-1 gene. The rat apobec-1 gene spans 16 kb and includes one untranslated (exon A) and five translated exons (exons 1-5). The mouse apobec-1 gene contains eight exons, of which the first three (exons A, B, C) are untranslated. Independent approaches demonstrated three distinct clusters of transcription initiation sites in both species, including exon A, the distal region of exon 1, and a separate group in the proximal region of exon 1. These transcription start sites generate three distinct mRNA species whose proportions differ in a tissue-specific fashion. Promoter-luciferase reporter constructions using regions flanking exon A and exon 1 of the rat apobec-1 gene identified two functional regions upstream of exon 1 that independently promote luciferase expression in transfected hepatoma and colon cancer cells. These data serve as a basis for an understanding of the regulation of apobec-1 gene expression, in particular the mechanisms that serve to restrict its expression to the gastrointestinal tract in higher mammals.
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PMID:Cloning and characterization of the rat apobec-1 gene: a comparative analysis of gene structure and promoter usage in rat and mouse. 921 39

Cross-linking of Fas (CD95, APO-1) and Fas ligand (FasL; CD95L) induces apoptosis of Fas-bearing cells. Recent evidence suggests that FasL. expression plays an important role in maintenance of immune privilege in murine testis and eye and in tumour escape from immune rejection in colon cancer, melanoma and hepatocellular carcinoma. Bcl-2 is a membrane protein that suppresses apoptosis in response to a variety of stimuli. In this paper we describe abundant expression of FasL protein and mRNA transcripts within the immune privileged environment of the placenta by immunohistochemistry and reverse transcription in-situ polymerase chain reaction methods. The syncytiotrophoblast layer, the main site of feto-maternal interface, and extravillous trophoblasts, demonstrated consistent immunoreactivity for FasL in term placentae. Co-occurrence of Fas and Bcl-2 were detected with a similar pattern of distribution with FasL. The TUNEL method revealed evidence of apoptosis in the placental tissues. We speculate that abundant presence of FasL in the trophoblast contributes to immune privilege in this unique environment, perhaps by fostering apoptosis of activated Fas-expressing lymphocytes of maternal origin. An apoptotic process mediated by FasL may also play a role in placental invasion during implantation and underscores similarities between the trophoblast and neoplastic cells.
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PMID:Trophoblasts express Fas ligand: a proposed mechanism for immune privilege in placenta and maternal invasion. 929 48

We used a yeast functional assay (functional analysis of separated alleles in yeast: FASAY) to determine the p53 gene status of human cell lines maintained in our laboratory. This assay enables the researcher to score wild-type p53 expression on the basis of the ability of expressed p53 to transactivate the reporter gene HIS 3 via the p53-responsive GAL 1 promoter in Saccharomyces cerevisiae. The cell lines examined were ten hepatoma, two hepatoblastoma, three in vitro immortalized fibroblast, two osteosarcoma, a chondrosarcoma, an ovarian teratocarcinoma and a colon cancer cell line. Out of 20 cell lines, 11 cell lines had mutations in both alleles of the p53 gene, and another 8 cell lines had no mutation in the p53 gene. Thus, 55% of the cell lines examined had mutations in the p53. Interestingly, PA-1 cells had both the normal and the mutant p53 alleles, showing that FASAY is a useful method for detecting the wild-type and mutated p53 genes simultaneously. As for the three liver cell lines harboring HBsAg, there was no relationship between their p53 gene status and the presence of HBsAg. Two cell lines were normal for p53 status, while the other had a mutation of the p53 gene.
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PMID:Yeast functional assay of the p53 gene status in human cell lines maintained in our laboratory. 935 23


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