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 incidence of hepatocellular carcinoma (HCC) is increasing in the United States. Several modalities are available for the treatment of HCC, and decisions regarding the optimal choice of therapy are based on tumor burden and severity of liver disease. Classification systems are helpful for prognostic purposes and to guide in the choice of therapy. Surgical resection is a mainstay of therapy for patients with solitary small tumors and preserved liver function (noncirrhotic or Child-Pugh class A cirrhotic patients without portal hypertension). Unfortunately, a minority of patients is eligible for resection, and postoperative recurrence or de novo HCC is common. Liver transplantation offers the best chance of curing HCC in cirrhotic patients. Patients with a solitary tumor less than 5 cm or no more than three tumors each 3 cm or less have a survival rate of 70% with less than 20% recurrence at 5 years. Access to liver transplantation is limited by organ availability, and tumor progression during the waiting period can lead to ineligibility. Ethanol injection and radiofrequency ablation are effective modalities to ablate small tumors (generally <5 cm) in patients who are not candidates for resection or liver transplantation. These modalities can also be used to treat HCC prior to liver transplantation. Transarterial chemoembolization is used to treat patients with multifocal or large HCC who are ineligible for other therapies. Chemotherapeutic agents are infused into the tumor via the hepatic artery along with embolic material in order to induce tumor necrosis. This technique should be used in selective patients with relatively preserved liver function, absence of portal vein thrombosis, or encephalopathy. Limited data exist to support the use of this modality as a primary treatment option for small HCC. Chemotherapeutic or hormonal therapies have a limited role in the management of patients with HCC. Despite mixed outcomes, we routinely use the somatostatin analog octreotide in advanced, multifocal HCC. Emerging therapies should focus on treatment of small tumors and targeted pharmacologic therapy for advanced disease.
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PMID:Treatment of Hepatocellular Carcinoma. 1458 35

The cAMP-response element-binding protein (CREB) transcription factor was initially identified as a mediator of cAMP-induced gene expression. CREB binds to a target sequence termed the cAMP-response element (CRE) found in many cellular and viral gene promoters. One of the best-characterized CREs resides in the promoter of the gene encoding the neuropeptide somatostatin, and this element has served as a model for studies of CREB function. Phosphorylation of CREB by protein kinase A allows recruitment of the coactivator CREB-binding protein (CBP). A central tenet of the CREB-CBP model is that CREB binds constitutively to the CRE and that regulation occurs through the phosphorylation-dependent recruitment of CBP. In this report, we use chromatin immunoprecipitation assays to show that CREB does not interact in vivo with the somatostatin CRE, or similar elements in several other genes, in PC12 cells, a standard model for studies of CREB function. Rather, CREB binding in vivo is regulated in a cell-specific manner, a finding that was confirmed by using in vivo genomic footprinting assays. The CREs in other genes were also found to interact differentially with CREB in PC12 cells, hepatoma cells, and cortical neurons. We conclude that the family of CREB target genes differs from one cell type to another and that the ability of CREB to bind to a particular CRE represents an important component of gene regulation.
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PMID:Cell-type-specific binding of the transcription factor CREB to the cAMP-response element. 1534 15

For more than 50 years now, nuclear medicine has offered therapeutic procedures in oncology. These comprise bone pain palliation in bone metastases of prostate and breast cancer. For more than 20 years now, metaiodobenzylguanidine (mIBG) has been used to treat neuroendocrine tumors. Ten years ago, somatostatin analogues such as Y-90 Dotatoc became available for the treatment of somatostatin receptor-positive tumors. The intracavitary injection of radiocolloids has been well known for 5 decades now and can be used in malignant effusions. Invasive procedures such as intra-arterial injection of I-131 lipiodol may be applied in multifocal, nonresectable hepatocellular carcinoma. Beyond that, intratumoral injection of radioisotopes may be used in cutaneous metastases. Radioimmunotherapy using labeled tumor antibodies is now also available, especially in patients with non-Hodgkin's lymphoma.
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PMID:[Therapy with radioisotopes in oncology. Palliative and curative approaches]. 1571 3

We have characterised the transdifferentiation of human HepG2 (hepatoma) cells to pancreatic cells following introduction of an activated version of the pancreatic transcription factor Pdx1 (XlHbox8-VP16). The following questions are addressed: (1) are all types of pancreatic cells produced? (2) is the requirement for expression of the transgene temporary or permanent? (3) are the transdifferentiated beta-cells responsive to physiological stimuli? The results showed that both pancreatic exocrine cells (by detection of amylase protein), and endocrine cells (by detecting insulin, glucagon and somatostatin proteins) are induced after XlHbox8VP16 transfection. Moreover, the hepatic phenotype becomes suppressed during transdifferentiation of hepatocytes to pancreatic cells. Requirement for the transgene is only temporary and it is no longer required once the pancreatic differentiation program is activated. Finally, we provided results to suggest that the transdifferentiated cells are functional by detecting: (1) functional markers for pancreatic beta-cells including prohormone convertase 1/3 (PC1/3), insulin C-peptide and glucagon-like peptide 1 receptor (GLP-1R), (2) increased insulin mRNA expression after treatment of cells with GLP-1 and betacellulin, physiological stimuli that regulate pancreatic function and (3) elevated insulin secretion after glucose challenge. The transdifferentiation of hepatic to pancreatic cells represents one possible source of beta-cells for human islet transplantation and this study shows that such a transdifferentiation can be achieved in vitro.
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PMID:In vitro transdifferentiation of hepatoma cells into functional pancreatic cells. 1593 30

Disorientation, muscle fasciculations and weakness seen in a 12-year-old neutered female domestic shorthaired cat were attributed to hypoglycaemia associated with a large hepatoma. Glucagon tolerance tests on this cat and a healthy cat showed that their plasma glucose concentrations increased and decreased at about the same rate. Plasma insulin concentrations in the healthy cat increased and decreased in parallel with the plasma glucose concentration. In the affected cat, plasma insulin concentrations increased initially but decreased more rapidly. Reflecting these observations, the amended insulin to glucose ratios in the affected cat were much lower than those of the healthy cat, until the 4-hour sample. Serum somatostatin, somatomedin and gastrin concentrations were measured but no conclusions as to pathogenesis of the hypoglycaemia could be made. The alterations in insulin secretion in the affected cat suggested that altered hormonal control of glucose homeostasis may have occurred with this tumour.
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PMID:Observations on hypoglycaemia associated with a hepatoma in a cat. 1603 47

Octreotide may extend survival in hepatocellular carcinoma (HCC). Forty-one per cent of HCCs have high-affinity somatostatin receptors. We aimed to determine the feasibility, safety, and activity of long-acting octreotide in advanced HCC; to identify the best method for assessing somatostatin receptor expression; to relate receptor expression to clinical outcomes; and to evaluate toxicity. Sixty-three patients with advanced HCC received intramuscular long-acting octreotide 20 mg monthly until progression or toxicity. Median age was 67 years (range 28-81 years), male 81%, Child-Pugh A 83%, and B 17%. The aetiologies of chronic liver disease were alcohol (22%), viral hepatitis (44%), and haemochromatosis (6%). Prior treatments for HCC included surgery (8%), chemotherapy (2%), local ablation (11%), and chemoembolisation (6%). One patient had an objective partial tumour response (2%, 95% CI 0-9%). Serum alpha-fetoprotein levels decreased more than 50% in four (6%). Median survival was 8 months. Thirty four of 61 patients (56%) had receptor expression detected by scintigraphy; no clear relationship with clinical outcomes was identified. There were few grade 3 or 4 toxicities: hyperglycaemia (8%), hypoglycaemia (2%), diarrhoea (5%), and anorexia (2%). Patients reported improvements in some symptoms, but no major changes in quality of life were detected. Long-acting octreotide is safe in advanced HCC. We found little evidence of anticancer activity. A definitive randomised trial would identify whether patients benefit from this treatment in other ways.
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PMID:Somatostatin receptor expression, tumour response, and quality of life in patients with advanced hepatocellular carcinoma treated with long-acting octreotide. 1750 6

Opioids, acting via G-protein coupled membrane receptors, induce analgesia. However their role is not limited to their anti-nociceptive action. They are found in several peripheral tissues acting as negative regulators of cellular processes. Even though that is not fully elucidated, it becomes obvious that opioids exert their effects in close relation to other neuropeptides such as somatostatin. Hepatocellular carcinoma is one tumor, among others, which secrete bioactive peptides while somatostatin analogs exert an inhibitory effect. We have used the human hepatocyte-derived cancer cell line HepG2, in order to examine the effect of opioids on cell growth and their possible mode of action. Our results show that the opioid ethylketocyclazocine (EKC) inhibits cell proliferation and induces apoptosis. This inhibitory effect is not exerted via opioids receptors since it was not reversed by the opioid antagonist diprenorphine and functional opioid receptors were not found on HepG2 cells. On the contrary, we show that EKC binds to somatostatin receptors, and activates a PTP signalling cascade. In this respect, the interaction of opioids with somatostatin receptors on hepatocellular carcinoma cells, and the fact that they are widely used for pain control, may provide some additional clues for the discrepancies during treatment with somatostatin analogues.
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PMID:The inhibitory effect of opioids on HepG2 cells is mediated via interaction with somatostatin receptors. 1711 72

In recent years, a number of new developments in targeted therapies using radiolabeled compounds have emerged. New developments and insights in radioiodine treatment of thyroid cancer, treatment of lymphoma and solid tumors with radiolabeled monoclonal antibodies (mAbs), the developments in the application of radiolabeled small receptor-specific molecules such as meta-iodobenzylguanidine and peptides and the position of locoregional treatment in malignant involvement of the liver are reviewed. The introduction of recombinant human thyroid-stimulating hormone and the possibility to enhance iodine uptake with retinoids has changed the radioiodine treatment protocol of patients with thyroid cancer. Introduction of radiolabeled mAbs has provided additional treatment options in patients with malignant lymphoma, while a similar approach proves to be cumbersome in patients with solid tumors. With radiolabeled small molecules that target specific receptors on tumor cells, high radiation doses can be directed to tumors in patients with disseminated disease. Radiolabeled somatostatin derivatives for the treatment of neuroendocrine tumors are the role model for this approach. Locoregional treatment with radiopharmaceuticals of patients with hepatocellular carcinoma or metastases to the liver may be used in inoperable cases, but may also be of benefit in a neo-adjuvant or adjuvant setting. Significant developments in the application of targeted radionuclide therapy have taken place. New treatment modalities have been introduced in the clinic. The concept of combining therapeutic radiopharmaceuticals with other treatment modalities is more extensively explored.
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PMID:Targeted therapy in nuclear medicine--current status and future prospects. 1743 93

The present study investigated the presence of somatostatin receptor subtypes (ssts) and the endogenous peptides somatostatin and cortistatin in rat Kupffer cells, since modulation of these cells by somatostatin may be important for the beneficial effect of somatostatin analogues in a selected group of hepatocellular carcinoma patients. Kupffer cells were isolated from rat liver in agreement with national and EU guidelines. RT-PCR was employed to assess the expression of somatostatin, cortistatin and ssts in Kupffer cells. Western blot analysis and immunocytochemistry were employed to assess the expression and the localization of the receptors, respectively. Quiescent Kupffer cells were found to express sst(1-4) mRNA, while immunocytochemical studies supported the presence of only the sst(3) and sst(4) receptors, which were found to be internalized. However, sst1 and sst(2A) receptors were detected by western blotting. RT-PCR and RIA measurements support the presence of both somatostatin and cortistatin. Stimulation of the cells with LPS activated the expression of the sst(2), sst(3) and sst(4) receptors. The present data provide evidence to support the presence of ssts and the endogenous neuropeptides somatostatin and CST in rat Kupffer cells. Both peptides may act in an autocrine manner to regulate sst receptor distribution. Studies are in progress in order to further characterize the role of ssts in Kupffer cells and in hepatic therapeutics.
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PMID:RT-PCR and immunocytochemistry studies support the presence of somatostatin, cortistatin and somatostatin receptor subtypes in rat Kupffer cells. 1748 46

Significant progress is being made in the prevention of hepatitis B-related hepatocellular carcinoma (HCC) but hepatitis C-related HCC is increasing in the West and therapeutic advances in established disease have been modest. Although ablative therapies, including surgical resection, seem effective in patients with small tumours these only represent a minority of patients. For the majority with advanced disease there is some evidence for survival benefit for transarterial chemoembolisation but only in very carefully selected patients. Systemic chemotherapy is of unproven benefit and is now largely confined to clinical trials. In contrast, there has been a steady improvement in the outlook of patients with established metastatic liver cancer when the primary site is colorectal. Survival has increased from around six months to almost two years with the introduction of new cytotoxic agents, irinotecan and oxaliplatin. Somatostatin analogues have had a dramatic impact on the symptomatic control of neuroendocrine tumours, metastatic to the liver that result in the carcinoid syndrome.
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PMID:New medical options for liver tumours. 1788 51


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