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)

Of 190 sets selective celiac and/or hepatic angiograms obtained in patients with hepatocellular carcinoma (HCC), comparison with gross anatomy of the liver was subsequently made by autopsy in 77 and by surgery in 23. It was found that the gross anatomy of HCC can be assessed with certain accuracy by careful interpretation of the angiograms, because tumor vasculature and vascular alterations in the noncancerous parenchyma are closely related to the mode of tumor growth, size of tumor nodules and their distribution. Even a fibrous capsule of the tumor may be discerned as a radiolucent zone around the tumor contour. Diagnosis of the gross anatomical type of HCC is important to the selection of therapeutic measure and assessment of prognosis.
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PMID:Angiographic assessment of gross anatomy of hepatocellular cardinoma: comparison of celiac angiograms and liver pathology in 100 cases. 19 72

Polyclonal 131I rabbit anti-rat ferritin localizes in the H-4-II-E hepatoma model. The effect of tumor size, vascularity, and ferritin content on tumor localization was examined. The extravascular and intravascular quantity and location of 131I non-specific IgG and 131I-antiferritin IgG in tumors were determined by gamma counter analysis of tissue samples and autoradiography. Separate groups of 8-10 tumor bearing rats with 0.6-1 g, 1-3 g, 4-8 g, 8-14 g, and greater than 14 g tumors were injected with 500 microCi (200 micrograms) of 131I non-specific IgG or 131I-antiferritin. Tumor targeting with antiferritin occurred maximally in primary or metastatic lesions less than 1 g in size. Decreased localization occurred with increasing tumor size and no localization took place in tumors greater than 8 g in size. This finding is independent of administered dose because increasing the amount of injected antiferritin from 2- to 10-fold did not increase the antiferritin/normal IgG targeting ratio in any group of tumors greater than 4 g. The quantity and physical characteristics of the tumor vasculature may in part explain selective tumor localization. Tumor vascularity per gram as measured by 51Cr labeled erythrocytes decreased as tumor size increased. Decreased localization was evident in the necrotic portions of large tumors. Autoradiography of tumor sections revealed that most of the 125I-IgG activity is deposited perivascularly with decreased deposition of antibody in necrotic areas of tumors and at increasing distance from the lumen of vessels. These findings have clinical importance since this non-homogeneous distribution of antibody could result in the delivery of low doses of radiation to large necrotic areas of tumors. These results help to demonstrate some of the complex physiologic factors that affect tumor localization and antibody distribution.
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PMID:Distribution of and physiologic factors that affect 131I-antiferritin tumor localization in experimental hepatoma. 674 54

In trying to clarify the high recurrence rate after removal of small hepatocellular carcinoma (HCC), we assessed the postoperative evolution of minute hepatic Lipiodol deposits which had been diagnosed as artifacts on the preoperative Lipiodol-CT. Of 27 patients with solitary HCC less than 5 cm in diameter, 14 had such Lipiodol deposits in the preoperative CT and 9 of them (64%) developed recurrent tumors. On the other hand, 6 of the 13 patients without deposits (46%) suffered recurrence, but in 5 of these 6 patients the HCC was metachronous multicentric. The cumulative survival rate of the non-deposit group was better than that of the deposit group (p < 0.1). The present study suggested that, even in patients with small HCC, minute concomitant tumors invisible by conventional imaging techniques may exist at the time of surgery. Some of these lesions without sufficient tumor vasculature showing a hypervascular blush on angiography appear to retain small, vague Lipiodol deposits.
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PMID:Prediction of recurrence after HCC resection. Faint oily deposits on preoperative Lipiodol-CT of remnant liver tissue. 801 80

We have evaluated gene transfer efficiency to tumor nodules in diethylnitrosoamine (DENA)-induced hepatocellular carcinoma (HCC) in rats using adenoviral vectors administered by three different routes: intraportal, intra-arterial and intratumoral injection. Our results showed that intraportal infusion could not transduce tumor nodules greater than 1 mm in diameter while the intra-arterial route allowed transduction of nodules up to 2-5 mm in diameter. Tumors greater than this size were resistant to transduction by intravascular route, but could be transduced by direct intratumoral injection, indicating that the obstacle preventing gene transfer to tumor cells was mainly at the level of tumor vasculature and not at the level of neoplastic cells. We have studied the extracellular matrix in tumoral lesions to assess whether nodules with different size and histological pattern have different profiles in relation to transduction efficacy. Immunohistochemical detection showed a high expression of fibronectin (FN), laminin (LN) and alpha-smooth muscle actin (alpha-SMA) in those large HCC, which were resistant to adenoviral infection. Intra-arterial infusion of vasoactive compounds (histamine, angiotensin II or nitric oxide donor nitroglycerin) before vector administration enhanced gene transfer to tumor nodules that were poorly transduced without pre-treatment. Nitroglycerin was active to enhance transduction of large tumors with trabecular or pseudoglandular histological pattern, which were impermeable to adenoviral vectors even after histamine or angiotensin treatments. Our data indicate the presence of a physical barrier between blood and neoplastic cells, which prevents transduction of the tumor by vectors given by the intravascular route. The thickness and impermeability of the barrier increases as the tumor nodule grows. Vasoactive compounds may be of value in gene therapy of liver cancer by increasing transduction efficiency by intravascularly administered vectors.
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PMID:A blood-tumor barrier limits gene transfer to experimental liver cancer: the effect of vasoactive compounds. 1111 Apr 14

A technique that can measure tumor blood flow easily, accurately and economically is required to study tumor angiogenesis and angiogenesis inhibition. Using dye extraction colored microspheres, we measured tumor blood flow in Sato lung carcinoma (SLC) and ascites hepatoma LY80 in rats. Colored microspheres were infused into tumor-bearing rats via a catheter in the left ventricle. After removal of the tumor and the liver, the tissue samples were dissolved, and the microspheres were isolated. Dye was extracted, and the dye concentration was quantified by spectrophotometry. The dye concentration per gram of tumor was compared with that per gram of liver as follows (AU = absorbency units): [AU per gram of tumor] / [AU per gram of liver] X 100 = (%). Tumor blood flow corrected for wet weight was calculated as follows: [blood flow to tumor] = [AU per gram of tumor] X [reference withdrawal rate] / [AU per gram of reference blood]. Tumor blood flow rate was divided by tumor weight to yield ml. min-1g-1. The tumors were also examined histologically, and casts of the tumor vasculature were prepared with silicone rubber. Blood flow 2 weeks after transplantation was equivalent to 1/10 and 1/2 at 1 week in SLC and LY80 tumors, respectively (SLC, P=0.009, n=10; LY80, P=0.05, n=10). These decreases in tumor blood flow were associated with underlying pathological and vascular change. Blood flow in LY80 tumors negatively correlated with tumor volume (P=0.009, n=10). We concluded that the colored microsphere method, initially developed to measure organ blood flow, is also useful for estimating tumor blood flow in rats.
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PMID:Measurement of tumor blood flow using colored dye extraction microspheres in two rat tumor models. 1117 86

Gene therapy may become an option for the treatment of malignant tumors such as hepatocellular carcinoma (HCC), once safe and efficient vector systems have been established. Due to their stability in vivo, recombinant adenoviral vectors are promising vectors for gene delivery to HCC. To study the characteristics of gene delivery into HCCs by recombinant adenoviral vectors in vivo, we established an in situ HCC model in the livers of athymic nude mice by intrahepatic injection of human HCC cells. Recombinant adenovirus vectors expressing beta-galactosidase (Ad2CMV beta gal) were injected via the tail vein of mice bearing HCC or directly into intrahepatic tumors. Levels of beta-galactosidase expression in tumor tissue and surrounding normal liver were analyzed by histochemistry or for quantification by a chemiluminescence assay in tissue homogenates. Following tail vein injection, high levels of beta-galactosidase expression were found in the liver, but virtually no gene expression could be detected in the tumor tissue. In contrast, after direct injection of Ad2CMV beta gal into intrahepatic HCCs, high levels of beta-galactosidase expression were detected in the tumor tissue. However, single transduced hepatocytes scattered throughout the normal liver could also be identified. These results indicate that barriers such as the endothelial lining of the tumor vasculature impair the efficiency of adenoviral vectors for gene delivery into HCCs by intravenous administration, which can be overcome by direct injection into the tumor tissue. However, due to the observed transduction of disseminated hepatocytes following intratumoral administration, additional HCC-specific targeting to further enhance the safety of adenoviral vectors may be required.
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PMID:Adenovirus-mediated gene transfer to orthotopic hepatocellular carcinomas in athymic nude mice. 1157 35

Both enhanced vascular permeability and angiogenesis of tumor sustain rapid growth of tumor involving many vascular mediators and high vascular density. On the contrary, however, they can be utilized for macromolecular drug delivery to tumor. Impaired reticuloendothelial/lymphatic clearance of macromolecules from the tumor, or lack of such clearance, is another unique characteristic of tumor tissue, which results intratumor retention of macromolecular drugs thus delivered (Figure 1). Consequently, enhanced permeability and retention (EPR) effect is the basis for the selective targeting of macromolecular drugs to tumor, and the EPR concept is now utilized for selective delivery of many macromolecular anticancer agents in aqueous formation for i.v. or i.a. as well as oily formation for i.a. dosing, which is not possible for low-molecular-weight drugs because of rapid washout by capillary vascular blood flow. This EPR concept has been validated in clinical settings with hepatoma and other solid tumors. In our laboratories, several promising macromolecular anticancer drugs after SMANCS, such as PEG-XO, PEG-DAO, PEG-ZnPP, were developed, warranting further investigation for clinical application. More efficient drug delivery to tumor, especially of macromolecular drugs, may be possible by enhancing the EPR effect with the use of various vascular permeability mediators or potentiators. Suppression of the EPR effect by the use of appropriate inhibitors or antidotes, such as the bradykinin antagonist HOE 140 and protease inhibitors or NOS inhibitors, may also be possible. Thus, one may be able to suppress or retard tumor growth and tumor metastasis. Also, by suppressing vascular permeability with antidotes such as the bradykinin antagonist HOE 140, pleural fluid in lung cancer and ascitic fluid in abdominal carcinomatosis may be controlled and the clinical course of cancer patients may be improved. In summary, tumor vasculature can be an excellent target for delivery of macromolecular anticancer drugs; the most beneficial class of drugs in view of tumor-selective targeting based on the EPR effect in solid tumor as well as compliance of patients and ultimate therapeutic efficacy.
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PMID:Factors and mechanism of "EPR" effect and the enhanced antitumor effects of macromolecular drugs including SMANCS. 1267 6

A multifocal mouse liver tumor model chemically induced with 5,9-dimethyl-7H-dibenzo[c,g]carbazole was investigated by respiratory-triggered morphological and functional MRI (fMRI) at 4.7 Tesla. The model is characterized by the presence of two tumor types: hypovascular cholangioma and vascularized hepatocellular carcinoma (HCC). Growth curves measured by 3D-MRI showed limited growth of cholangiomas and rapid growth of HCCs after a latency of about 25 weeks. Functional imaging based on T(2) (*)-weighted fast gradient-echo MRI and carbogen breathing was optimized for liver imaging in mice. A response to carbogen was observed in HCCs but not in cholangiomas. Transversal analysis (50 HCCs) of signal change upon carbogen revealed four different types of response patterns: 1) signal increase upon carbogen administration (74%); 2) small or insignificant signal change (10%), 3) transient signal decrease and delayed increase (8%), and 4) signal decrease (8%). Longitudinal follow-up of a subgroup (N = 17) showed that an initially observed type 1 response, attesting to the presence of a functional vasculature, remained stable for at least 3 weeks in 14 HCCs. A switch from a type 1 response to another response type may be useful for demonstrating, in a noninvasive manner, a disturbance of tumor vasculature induced by anti-vascular or anti-angiogenic therapy.
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PMID:Morphological and carbogen-based functional MRI of a chemically induced liver tumor model in mice. 1293 60

Vascular targeting is a novel strategy that directs endothelial toxins at tumor vessels expressing specific markers and kills tumor cells by vascular occlusion. Integrin-binding RGD motif has been reported to have a homing property to experimental tumor vasculature. In the present study, we evaluated the effect of vascular targeting by doxorubicin-RGD-4C conjugate in an orthotopic murine hepatoma model. MTT assay showed that dox-RGD-4C conjugates had lower cytotoxicity against MH134 mouse hepatoma cells than free dox. When given intravenously to mice with implanted orthotopic hepatoma, however, the dox-RGD-4C suppressed the growth of hepatoma more effectively than free dox (mean tumor volumes 24 mm(3) vs. 67 mm(3), respectively; p=0.047). Histologic analysis of the hepatoma tissue revealed prominent tumor cell death in the dox-RGD-4C treated group and complete tumor cell necrosis in 40% of cases. Immunochemical staining showed expression of integrin alphav mainly around the tumor nodule. These results show that dox-RGD-4C conjugate has a better antitumor effect in an orthotopic mouse hepatoma model by tumor targeting. Integrin alphav of hepatoma feeding vessels is suggested to be targeted by the dox-RGD-4C conjugate.
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PMID:Tumor targeting by doxorubicin-RGD-4C peptide conjugate in an orthotopic mouse hepatoma model. 1537 78

Improvements in our understanding of the molecular basis of cancer have led to the clinical development of protein kinase inhibitors, which target pivotal molecules involved in intracellular signaling pathways implicated in tumorigenesis and progression. These novel targeted agents have demonstrated activity against a wide range of solid tumors, are generally better tolerated than standard chemotherapeutics, and may revolutionize the management of advanced refractory cancer. The ubiquitous Raf serine/threonine kinases are pivotal molecules within the Raf/mitogen extracellular kinase (MEK)/extracellular signal-related kinase (ERK) signaling pathway, which regulates cellular proliferation and survival. Raf kinase isoforms (wild-type Raf-1 or the b-raf V600E oncogene) are overactivated in a variety of solid tumor types, including renal cell carcinoma (RCC), hepatocellular carcinoma (HCC), non-small cell lung cancer (NSCLC), melanoma, and papillary thyroid carcinoma. In this review, the role of Raf in normal cells and in cancer is discussed, and an overview is given of Raf inhibitors currently in development, focusing on sorafenib tosylate (BAY 43-9006 or sorafenib). Sorafenib is the first oral multi-kinase inhibitor to be developed that targets Raf kinases (Raf-1, wild-type B-Raf, and b-raf V600E), in addition to receptor tyrosine kinases associated with angiogenesis (vascular endothelial growth factor receptor [VEGFR]-2/-3, platelet-derived growth factor receptor [PDGFR]-beta) or tumor progression (Flt-3, c-kit). Preclinical and clinical sorafenib data that led to its recent approval for the treatment of advanced RCC are summarized, along with current thinking on sorafenib's mechanism of effect on the tumor and tumor vasculature in melanoma and RCC.
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PMID:Role of Raf kinase in cancer: therapeutic potential of targeting the Raf/MEK/ERK signal transduction pathway. 1689 Jul 95


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