Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0345904 (liver cancer)
 15,188 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The 20-year period since the discovery of AFP by Abelev has seen the introduction of a wide range of new tumour markers and it is now clear that PLC is biologically heterogeneous. Hepatoblastomas, fibrolamellar carcinomas, hepatocellular carcinomas and cholangiocarcinomas may secrete a variety of distinctive markers which are predominantly glycoproteins, and may resemble those found in placenta or fetal liver. Diagnostically, AFP remains the best marker for HCC, both in sensitivity and specificity; it is known to consist of isoforms. In patients with elevated serum AFP and filling defects on liver scan, Con A reactive AFP may differentiate PLC from hepatic metastases, whilst fucosylated AFP may distinguish PLC from benign disorders when AFP is non-diagnostically elevated. With this recognition of tumour heterogeneity the value of a multiple-marker approach has become apparent. The measurement of vitamin B12 binding protein and neurotensin should lead to the detection of most patients with the fibrolamellar variant of HCC and many of these should be resectable. In patients with normal serum AFP levels, HCC-associated GGTP is of major value whilst in low-incidence areas for HCC, patients should also be screened for H-ALP; using a multiple marker approach in high-risk groups, 90% of clinically diagnosed hepatocellular carcinomas are serologically positive. The Chinese and Alaskan studies, in which small, potentially resectable tumours were detected, suggest that it is now possible to achieve 5-year survival figures of up to 60% in HCC patients detected by screening. The value of such a strategy in low-incidence countries is currently under study. In patient monitoring, as in diagnosis, AFP remains the outstanding marker. In AFP-negative patients, other markers including vitamin B12-binding protein, neurotensin, HCC-specific isoenzymes, des-gamma-carboxy-prothrombin and alpha-fucosidase, are of undoubted diagnostic value, but their value as indicants of disease progression remains to be established. In monitoring the response of hepatic metastases, CEA remains the least unsatisfactory marker but should always be used in conjunction with serial ultrasound scans. Tumour markers now play an important role in the diagnosis and monitoring of PLC but a role is also emerging in tumour imaging and drug targeting. The next 20 years should see the introduction of tumour markers of high sensitivity and specificity which make a fundamental contribution not only to detection and monitoring, but also to the effective treatment of liver cancer.
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PMID:Tumour markers in diagnosis and management. 243 83

Unlike hepatocellular hepatoma (HCC), the so-called fibrolamellar hepatoma (FLH) is found almost exclusively in the non-cirrhotic, non-infected liver. Patient characteristics and the course of the disease in FLH differ markedly from HCC. FLH represents only a small portion of hepatomas in general (approx. 2%), but accounts for over 40% of hepatomas in young adults. We present the case of a 38-year-old woman showing the typical histological findings of polygonal eosinophilic tumor cells and characteristic lamellar bundles of fibrous stroma, which led to the diagnosis of FLH. The approx. 140 cases of FLH published in the world literature are also presented and discussed. The usefulness of additional examinations (neurotensin, vitamin B12 binding capacity and copper stains) is mentioned. The difficulty in diagnosing FLH lies in its histological differentiation from focal nodular hyperplasia. When diagnosed early, however, FLH is characterized by good resectability with a chance of cure or at least a markedly better survival rate than HCC.
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PMID:[Fibrolamellar hepatoma]. 302 Jun 85

The lipotropes (choline, methionine, folate, and vitamin B12) have a rich history, with many fluctuations in scientific effort and popularity, covering the past 6 decades. A thin thread of common interest in 1-carbon metabolism and a small band of dedicated individuals have kept this area of biology alive. Today, the lipotropes are enjoying a resurgence of interest and effort with promise for significant contributions to some of our most serious chronic diseases. Between 1920, when Banting and Best initiated a work that led to the discovery of insulin, and 1982-83, when investigators working in 3 laboratories announced that lipotrope deficiency alone could result in liver cancer in rodents, many have used this model to study nutritional problems and, more recently, carcinogenesis. Lipotropes are important to lipid metabolism and to synthesis and maintenance of cellular membranes. When weanling rats were fed a diet low in lipotropes, within a few days the liver accumulated lipid, first in the centrilobular zone and later throughout the entire lobule and lobe. If the diet was continued for a longer period, the liver underwent fibrosis and cirrhosis with some rats ultimately developing hepatocellular carcinoma. Although lipotrope deficiency can result in liver cancer, all hepatocarcinogens tested thus far were enhanced in their activity by diets low in lipotropes. Important changes associated with lipotrope deficiency included membrane damage, decreased serum very low density lipoprotein and drug metabolizing enzymes, decreases in S-adenosylmethionine and in methylation of cytosine, increases in cellular peroxidation products and free radicals, decreased immunocompetence, and a markedly shortened lag time for chemical induction of liver cancer in animals. The overall effect of lipotrope deficiency is an increase in the susceptibility to cancer in animals; the exact mechanisms are unclear.
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PMID:Lipotropic factors and oncogenesis. 303 98

Deficiencies of the major dietary sources of methyl groups, methionine and choline, lead to the formation of liver cancer in rodents. The most widely investigated hypothesis has been that dietary methyl insufficiency results in abnormal DNA methylation. Vitamin B12 and folate also play important roles in DNA methylation since these two coenzymes are required for the synthesis of methionine and S-adenosyl methionine, the common methyl donor required for the maintenance of methylation patterns in DNA. The aim of this study was to review the effects of methyl-deficient diets on DNA methylation and liver carcinogenesis in rats, and to evaluate the role of vitamin B12 status in defining carcinogenicity of a methyl-deficient diet. Several studies have shown that a methyl-deficient diet influences global DNA methylation. Evidence from in vivo studies has not clearly established a link between vitamin B12 and DNA methylation. We reported that vitamin B12 and low methionine synthase activity were the two determinants of DNA hypomethylation. Choline- or choline/methionine-deficient diets have been shown to cause hepatocellular carcinoma in 20-50% of animals after 12-24 months. In contrast, the effect of vitamin B12 withdrawal, in addition to choline, methionine and folate, induced hepatocellular carcinoma in less than 5% of rats.
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PMID:Effects of vitamin B12 and folate deficiencies on DNA methylation and carcinogenesis in rat liver. 1296 6

A chronic deficiency of major dietary methyl group donors--methionine, choline, folic acid, and vitamin B12--can induce the development of liver cancer in rodents. Feeding methyl-deficient diets causes several molecular alterations, including altered lipid metabolism, oxidative stress, deregulated one-carbon metabolism, and a number of epigenetic abnormalities that result in progressive liver injury culminating in the development of primary liver tumors. Importantly, this methyl-deficient model of endogenous hepatocarcinogenesis is one of the most relevant models of human liver carcinogenesis that allows studying liver cancer pathogenesis by substantially complementing many shortcomings of humans-only studies. In this review, we describe molecular changes and their role in pathogenesis of liver carcinogenesis induced by methyl deficiency.
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PMID:Molecular alterations in hepatocarcinogenesis induced by dietary methyl deficiency. 2209 81

Evidence is accumulating regarding a role of micronutrients in folate metabolism in cancer risk. We investigated the associations of plasma folate, vitamin B12, and homocysteine with upper gastrointestinal (GI) cancers in a population-based case-control study in Taixing City, China. With informed consent, we recruited cases with cancers of esophagus (n = 218), stomach (n = 206), and liver (n = 204), and one common healthy control group (n = 405). A standardized epidemiologic questionnaire was used in face-to-face interviews, and blood samples were collected during interviews. We observed an inverse association between plasma folate levels and liver cancer. The adjusted odds ratio (aOR) was 0.46 [95% confidence interval (CI) = 0.24-0.88] comparing individuals in the highest quartile to those in the lowest. We found a positive association between plasma vitamin B12 levels and all three cancers. The aORs for those in the highest quartile were 2.80 (95% CI = 1.51-5.18) for esophageal cancer, 2.17 (1.21-3.89) for stomach cancer, and 9.97 (4.82-20.60) for liver cancer, comparing to those in the lowest quartile. We further observed interaction between plasma folate and vitamin B12 on these cancers. Our data indicated associations between plasma folate and vitamin B12 with upper GI cancers in Chinese population. Further research is warranted considering the debate over the necessity of food fortification.
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PMID:Plasma folate, vitamin B12, and homocysteine and cancers of the esophagus, stomach, and liver in a Chinese population. 2560 98