Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0019204 (hepatocellular carcinoma)
 71,386 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

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

There is often a considerable lapse of time between the definition of what causes a disease in the laboratory and the development of successful therapy. However, the history of medicine teaches us that the need to understand the scientific basis of disease before the discovery of new treatments is both essential and inevitable. During the middle of the 19th century, the work of the great German pathologist, Rudolf Virchow, defined disease as having an anatomic or histologic basis. In the clinic, this scientific perspective would lead to increasingly effective and, often, increasingly aggressive surgical approaches to disease. Later in the 19th century, Koch's discovery of the tubercle bacillus (a discovery Virchow disbelieved and publication of which he thwarted, since he hypothesized that cancer, not microbes, caused consumption!), would define a microbiological basis for disease. With bacteria defined as a major cause of human suffering, the stage was set for the development of the discovery of effective antibiotics. In the early 20th century, the pioneering work of Banting, Best and others would show that disease can also have an endocrine or metabolic basis. This new body of scientific knowledge would lead not only to the specific discovery of insulin as an effective treatment for diabetes but also to a more general understanding of the role of hormones, vitamins and co-factors in human health and disease. Basic medical research and its successful translation into effective treatments has fundamentally altered the cause of human death. In the developed world, where access to the benefit of this work is available, infectious disease is not the problem it was in the days of Pasteur, Metchnikoff and Ehrlich. As we approach the millennium, science is now teaching us that diseases, particularly cancer, can have a molecular or genetic basis. Can successful application of this new knowledge be far behind? We are already seeing the application of this new knowledge in cancer drug screening and cancer drug development. At the NCI, for example, the old in vivo mouse screen using mouse lymphomas has been shelved; it discovered compounds with some activity in lymphomas, but not the common solid tumors of adulthood. It has been replaced with an initial in vitro screen of some sixty cell lines, representing the common solid tumors-ovary, G.I., lung, breast, CNS, melanoma and others. The idea was to not only discover new drugs with specific anti-tumor activity but also to use the small volumes required for in vitro screening as a medium to screen for new natural product compounds, one of the richest sources of effective chemotherapy. The cell line project had an unexpected dividend. The pattern of sensitivity in the panel predicted the mechanism of action of unknown compounds. An antifolate suppressed cell growth of the different lines like other antifolates, anti-tubulin compounds suppressed like other anti-tubulins, and so on. It now became possible, at a very early stage of cancer drug screening, to select for drugs with unknown-and potentially novel-mechanisms of action. The idea was taken to the next logical step, and that was to characterize the entire panel for important molecular properties of human malignancy: mutations in the tumor suppressor gene p53, expression of important oncogenes like ras or myc, the gp170 gene which confers multiple drug resistance, protein-specific kinases, and others. It now became possible to use the cell line panel as a tool to detect new drugs which targeted a specific genetic property of the tumor cell. Researchers can now ask whether a given drug is likely to inhibit multiple drug resistance or kill cells which over-express specific oncogenes at the earliest phase of drug discovery. In this issue of The Oncologist, Tom Connors celebrates the fiftieth anniversary of cancer chemotherapy. His focus is on the importance of international collaboration in clinical trials and the negative impact of unnecessary bureaucracy and regulation. As a student of Tom's in the 1970s in London, working on hepatoma-specific alkylating agents at Charing Cross Hospital in collaboration with his lab on the other side of town, I can attest to the fact that the regulatory hurdles to cancer drug development just twenty years later have added immeasurably to the effort and cost of cancer drug development. However, I look with optimism to the future of cancer diagnosis, prevention and treatment. It is a future where what we are learning now about the molecular and genetic basis of cancer will find their clinical outlet just as surely as the anatomic, microbial, metabolic and endocrine basis for disease has in the past. This new knowledge will provide new techniques in molecular diagnosis, which will allow us to predict which in situ cancers are destined for malignant behavior, and which can be safely watched without the need for intervention. Individual patient risk for particular cancers will be accurately predictable, so that patients can alter lifestyle habits or begin other prevention strategies. Oncogenes and growth suppressor genes give us new targets to inhibit or replace. Tumor-specific kinases will meet their inhibitors. The oncologist will play a leading role in understanding, applying and interpreting this new information in the clinic-an exciting and challenging future!
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PMID:Cancer Drug Development: New Targets for Cancer Treatment. 1038 87

Hepatitis B virus infection is the most common cause of chronic hepatitis, liver cirrhosis and hepatocellular carcinoma worldwide. In areas hyperendemic for HBV infection, the related complications occur mostly during adulthood. However, nearly half of all primary infection in chronic carriers occurs in the perinatal period through maternal transmission, the other half arising from horizontal transmission mainly through intrafamilial spread or injection using unsterilized needles. A universal vaccination programme is better than immunization for at-risk groups. Hepatitis B vaccination should be integrated into the Expanded Programme on Immunization in children. Universal immunization against hepatitis B virus has proved to be effective in reducing the hepatitis B carrier rate to one-tenth of the prevalence before the vaccination programme in highly endemic areas, and the incidence of hepatocellular carcinoma in children has also been shown to be significantly reduced. Continued efforts to implement universal vaccination programmes worldwide will very likely reduce the incidence of hepatitis B virus-related diseases, particularly liver cirrhosis and hepatocellular carcinoma.
Baillieres Best Pract Res Clin Gastroenterol 1999 Dec
PMID:Prospects for hepatitis B virus eradication and control of hepatocellular carcinoma. 1065 16

The sequential development of cirrhosis and hepatocellular carcinoma (HCC) in patients with transfusion-associated hepatitis was a clue leading to the identification of hepatitis C virus (HCV) as a risk factor for HCC. The incidence of HCV-related liver cancer is increasing in many developed countries: tumours arise in older patients, are almost invariably associated with cirrhosis and often have a less aggressive course than is seen in HCC related to other aetiological factors. Most HCCs grow as a single hepatic nodule for several years before generating satellite or distant tumour nodules. Tumour progression and hepatic failure are the leading causes of death. HCV might promote cancer through cirrhosis, which is per se an important risk factor for this tumour. HCV might also have oncogenic properties by interacting with cellular genes that regulate cell growth and differentiation. The primary prevention of HCC through vaccination against HCV is not yet available. The treatment of patients with chronic hepatitis C with interferon might attenuate the risk of HCC.
Baillieres Best Pract Res Clin Gastroenterol 1999 Dec
PMID:Hepatitis C virus and hepatocellular carcinoma. 1065 17

This chapter reviews the data that have been accumulated implicating aflatoxin ingestion as an important risk factor in the aetiology of hepatocellular carcinoma (HCC). Numerous epidemiological studies have observed a correlation between areas of high aflatoxin exposure and a high incidence of HCC. The use of experimental models and specific biomarkers for aflatoxin exposure, such as urinary metabolites or aflatoxin adducts, have validated these findings. Ongoing clinical trials in Qidong, China, have indicated that oltipraz, a chemopreventive agent, can lower the biologically effective dose of aflatoxins by decreasing the metabolism of aflatoxin to its carcinogenic form and increasing the detoxification pathways of these metabolites. Intervention with chemicals such as these, alongside hepatitis B virus immunization programmes and improved storage conditions of staple foods, are prevention measures that can be undertaken to reduce the incidence of HCC in high-risk regions.
Baillieres Best Pract Res Clin Gastroenterol 1999 Dec
PMID:Aflatoxin and liver cancer. 1065 19

Surgical resection is the mainstay of treatment for malignant liver tumours and offers the only chance of cure. Advances in radiological imaging, surgical technique and peri-operative management have enabled liver resection to be performed safely. Partial hepatectomy is indicated for the treatment of hepatocellular carcinoma and hepatic metastases from colorectal cancer. In addition, it may be utilized for selected patients with liver metastases from other primary tumours. Total hepatectomy with transplantation may be of benefit in some patients with unresectable neuroendocrine metastases or small hepatocellular carcinomas. The role of cryosurgery has not been precisely defined, and it needs to be compared with other palliative therapies such as ethanol injection and hepatic artery embolization.
Baillieres Best Pract Res Clin Gastroenterol 1999 Dec
PMID:Surgical treatment of malignant liver tumours. 1065 20

For many patients with malignant disease of the liver, liver transplantation offers the only opportunity for clinical cure or prolonged palliation. As a result of organ scarcity, patients are increasingly selected on the basis of tumour stage and with the predictable likelihood of prolonged survival in mind. Consequently, 3- and 5-year survival rates of 72% and 68% respectively have been described for patients transplanted with hepatocellular carcinoma for tumours measuring less than 5 cm in diameter or up to three in number. Moreover, many centres are developing adjuvant and neo-adjuvant therapeutic protocols to minimize the risks of disease recurrence following transplantation for malignancy. In this chapter, we review the current knowledge in relation to transplantation for hepatocellular carcinoma, fibrolamellar hepatocellular carcinoma, cholangiocarcinoma, metastatic neuroendocrine tumours, secondary solid tumours and other rarer malignancies.
Baillieres Best Pract Res Clin Gastroenterol 1999 Dec
PMID:Liver transplantation for malignant disease. 1065 21

Improvements in diagnostic techniques have enhanced our understanding of the natural history of hepatocellular carcinoma (HCC). This has facilitated a proper evaluation of the available treatment options for this neoplasm through both phase II studies and randomized controlled trials. Surgical resection and liver transplantation constitute the first two radical options, and when they are contra-indicated, patients may benefit from percutaneous ethanol injection or thermal ablation by radiofrequency current. These options may also achieve a complete response and constitute the last potentially radical therapies for small HCC. In contrast, for large multinodular tumours, the available treatment options have not been shown to improve survival. Arterial embolization with or without associated chemotherapy has been widely used. However, randomized controlled trials have failed to show a survival benefit, emphasizing the need to develop new treatment strategies.
Baillieres Best Pract Res Clin Gastroenterol 1999 Dec
PMID:Locoregional treatments for hepatocellular carcinoma. 1065 23

Screening for hepatocellular carcinoma has become widely practised in the management of patients with end-stage liver disease. However, the theoretical basis for this practice is largely lacking. Issues such as the selection of the target population and the correct method of confirming positive screening tests have yet to be resolved. Complicating the assessment of screening strategies is the poor literature on comparing different forms of therapy. Nonrandomized, uncontrolled studies that do not account for lead-time bias make it frequently impossible to know whether an applied treatment has really improved survival. Despite these difficulties, screening is reality, and strategies have to be devised to efficiently screen patients, find small tumours and apply effective treatments. Some practical strategies are discussed.
Baillieres Best Pract Res Clin Gastroenterol 1999 Dec
PMID:Screening for hepatocellular carcinoma. 1065 24

Hepatitis C virus (HCV) related chronic liver disease is now the leading cause for liver transplantation in many centres. Virological recurrence is inevitable following liver transplantation. Excellent patient and graft survival are seen in the short-term, equivalent to that in patients transplanted for other causes of liver disease. However, histological evidence of disease recurrence or hepatitis is present in over half the patients within a year of transplantation, although a small percentage develop progressive cholestatic hepatitis with graft loss within a year. Cirrhosis can develop in the first year after transplantation and 28% of patients have evidence of cirrhosis by 5 years. There is little agreement over the factors that predict the recurrence of disease, development of cirrhosis within the graft and graft or patient survival. Graft loss due to HCV occurs in up to 9% at 5 years and the long-term prognosis may not be comparable to groups transplanted for other diseases. Patients with hepatocellular carcinoma may benefit from liver transplantation if the tumour is small and without vascular invasion. There are, as yet, no clear guidelines regarding the best combination of immunosuppressants in patients with HCV but viral clearance has been achieved with the use of interferon and ribavirin therapy post-operatively.
Baillieres Best Pract Res Clin Gastroenterol 2000 Apr
PMID:Liver transplantation for hepatitis C virus related cirrhosis. 1089 Mar 24


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