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Background/aim: Unresectable recurrence after curative treatments for hepatocellular carcinoma (HCC) is a life-limited event. Although the IMbrave050 trial (IM050) showed a favorable reduction in recurrence with adjuvant immune-combination chemotherapy, inclusion criteria of the radiofrequency ablation (RFA) group were lower risk than that of the resection group. This study aimed to elucidate the clinical features of patients treated with RFA, which really need adjuvant-chemotherapy., Methods: From 2000 to 2022, 528 patients with Child-Pugh A and HCC within the Milan criteria (MC), who met the IM050 criteria for RFA and undergone resection or RFA, were enrolled (71 years, HCV:HBV:HBV/HCV:alcohol:others = 337:44:5:53:89, multi-tumor = 138, RFA:resection = 309:219). Unresectable recurrence was defined as beyond the MC. Risk factors for recurrence beyond the MC were retrospectively evaluated., Results: Multivariate Cox-hazard analysis showed HCV-positive (HR 1.49), AFP-L3 > 10% (HR 1.75), and DCP > 100 mAU/mL (HR1.80) as significant prognostic factors for recurrence beyond the MC (each P < 0.05). Summing of positive factors (1 point for each) was used for scoring (AD-ON score), which showed increased positive rates for micro-hepatic vein invasion (score 0:1:2:3 = 0%:1.1%:6.6%:15.8%), micro-portal vein invasion (0:1:2:3 = 2.0%:12.1%:14.1%:31.6%), and poor differentiation (0:1:2:3 = 6.0%:6.7%:15.3%:15.8%) in the resection group associated with a greater score (each P < 0.01). In patients treated with RFA, those with greater AD-ON scores showed shorter time to recurrence beyond the MC, recurrence-free time, and overall survival (score 0:1:2:3 = no-estimation:97:66:23 months, 35:27:20:12 months, and 91:82:67:52 months, respectively, each P < 0.05)., Conclusion: HCC patients treated by RFA and with a high AD-ON score (≧2) should be considered for aggressive adjuvant-chemotherapy to prolong the period of recurrence beyond the MC., (© 2024. Japanese Society of Gastroenterology.)

Introduction: For predicting esophagogastric varices (EGVs), the Virtual Baveno VII Consensus Workshop has proposed a combination of liver stiffness determination and platelet count measurement using a FibroScan®. However, FibroScan® is not available at all institutions. The present study aimed to develop a simple method to predict development of EGV using only general blood examination results., Materials and Methods: A total of 1,090 hepatocellular carcinoma patients were enrolled, after excluding 956 with major portal vein tumor thrombus (Vp3/Vp4) or without upper gastrointestinal endoscopy examination results available. Those with EGV (≥ grade F2) or a history of treatment for the condition were defined as positive for significant EGV, and then clinical factors were retrospectively evaluated to determine indicators of occurrence., Results: Logistic multivariate analysis showed platelet count (≤12 × 104/μL) (odds ratio [OR] 3.79, p &lt; 0.001), mALBI grade 2a (OR 1.52, p = 0.036), and mALBI 2b or 3 (OR 3.46, p &lt; 0.001) as significant predictive factors. Based on the OR values, platelet count (≤12 × 104/μL) and mALBI grade 2b/3 were each assigned 2 points and mALBI 2a was given 1 point, with the result termed recommendation for EGV screening (REGS) score. Significant EGV occurrence was noted in 2.9% (9/311) of the patients with a REGS score 0, 11.0% (13/118) with a score 1, 19.3% (53/274) with a score 2, 29.5% (39/132) with a score 3, and 38.0% (97/255) with a score 4 (p &lt; 0.001)., Conclusion: The findings indicate that REGS score can provide useful predictive information for development of significant EGV without the need for special equipment such as a FibroScan®., (© 2023 S. Karger AG, Basel.)

Acquired radioresistance of cancer cells interferes with radiotherapy and increases the probability of cancer recurrence. HepG2-8960-R, which is one of several clinically relevant radioresistant (CRR) cell lines, has a high tolerance to the repeated clinically relevant doses of X-ray radiation. In this study, HepG2-8960-R had slightly lower cell proliferation ability than HepG2 in the presence of FBS. In particular, epidermal growth factor (EGF) hardly enhanced cell proliferation and DNA synthesis in HepG2-8960-R. Additionally, EGF could not induce the activation of Erk1/2, because the expression of EGF receptor (EGFR) protein decreased in HepG2-8960-R in accordance with the methylation of the EGFR promoter region. Therefore, cetuximab did not inhibit HepG2-8960-R cell proliferation. Our study showed that HepG2-8960-R had radioresistant and cetuximab-resistant abilities., (Copyright © 2015 John Wiley & Sons, Ltd.)

Gankyrin (also called p28 or PSMD10) is an oncoprotein commonly overexpressed in hepatocellular carcinomas. It consists of 7 ankyrin repeats and interacts with multiple proteins including Rb, Cdk4, MDM2 and NF-κB. To assess the oncogenic activity in vivo, we produced transgenic mice that overexpress gankyrin specifically in the hepatocytes. Unexpectedly, 5 of 7 F2 transgenic mice overexpressing hepatitis B virus X protein (HBX) promoter-driven gankyrin, and one of 3 founder mice overexpressing serum amyloid P component (SAP) promoter-driven gankyrin developed hepatic vascular neoplasms (hemangioma/hemangiosarcomas) whereas none of the wild-type mice did. Endothelial overgrowth was more frequent in the livers of diethylnitrosamine-treated transgenic mice than wild-type mice. Mouse hepatoma Hepa1-6 cells overexpressing gankyrin formed tumors with more vascularity than parental Hepa1-6 cells in the transplanted mouse skin. We found that gankyrin binds to and sequester factor inhibiting hypoxia-inducible factor-1 (FIH-1), which results in decreased interaction between FIH-1 and hypoxia-inducible factor-1α (HIF-1α) and increased activity of HIF-1 to promote VEGF production. The effects of gankyrin were more prominent under 3% O2 than 1% or 20% O2 conditions. Thus, the present study clarified, at least partly, mechanisms of vascular tumorigenesis, and suggests that gankyrin might play a physiological role in hypoxic responses besides its roles as an oncoprotein., (Copyright © 2013 Elsevier Inc. All rights reserved.)

Hepatocellular carcinoma (HCC) is the most common primary cancer worldwide. The only current drug available for clinical treatment of HCC is sorafenib, which inhibits multiple signaling kinases including Raf family members, platelet-derived growth factor receptor, vascular endothelial growth factor receptors 1 and 2, c-Kit, and Fms-like tyrosine kinase 3. Many studies have revealed that the mechanism underlying the antitumor effect of sorafenib is complex. Because sorafenib inhibits C-Raf more potently than B-Raf, the therapeutic efficacy of sorafenib is strongly influenced by the relative expression and activity of B-Raf and C-Raf and the complex interactions between these factors. Moreover, Rafindependent signaling mechanisms have recently emerged as important pathways of sorafenib-induced cell death. Basic research studies have suggested that using sorafenib as part of a combination therapy may improve its effect, although this has yet to be confirmed by clinical evidence. Further studies of the functional mechanism of sorafenib are required to advance the development of targeted therapy for HCC. To aid future work on sorafenib, we here review the current literature pertaining to sorafenib signaling and its clinical efficacy in both monotherapy and combination therapy.

Hepatocellular carcinoma (HCC) has an aggressive clinical course with frequent recurrence and metastasis. Orthotopic liver transplantation has been the only curative tool for unresectable HCC; therefore, recent advances in molecular targeted therapy may improve the prognosis of HCC. The multiple kinase inhibitor sorafenib and the macrolide antibiotic rapamycin are currently the most promising agents for treating unresectable HCC. A large population-based clinical trial revealed that sorafenib significantly prolonged the overall survival of HCC patients. However, subsequent clinical studies showed that sorafenib rarely reduced tumor volume and inadequately prolonged survival of patients with severe liver damage. To improve its therapeutic effect, the development of a predictive biomarker and a sorafenib-based combination is awaited. Another molecular targeting agent, rapamycin, has now been considered as a putative agent for preventing tumor recurrence in post-liver transplantation HCC patients, because it not only has immunosuppressive activity but also exerts an anti-tumor effect. In the near future, a combination of molecular targeting agents, such as sorafenib and rapamycin, may become a standard protocol for treating unresectable HCC. For specifying cases with more effective and less harmful modalities, further investigation in clinical and basic research to identify unexpected effects are needed.

Exposure to internally deposited radionuclides is known to induce malignant tumors of various histological types. Thorotrast, a colloidal suspension of radioactive Thorium dioxide ((232)ThO(2)) that emits alpha-particles, was used as a radiographic contrast during World War II. Thorotrast is known to induce liver tumors, particularly intrahepatic cholangiocarcinoma (ICC) and angiosarcoma (AS), decades after injection. Therefore, patients injected with Thorotrast comprise a suitable study group to understand biological effects of internal ionizing radiation injury. Autoradiography and X-ray fluorescence spectrometry (XRF) were carried out on non-tumorous liver sections from Thorotrast-induced ICC (T-ICC) and Thorotrast-induced AS (T-AS). Autoradiography revealed that the slope of the regression line of the number of alpha tracks for the amount of deposited Thorium ((232)Th) was higher in non-tumorous parts of the liver with T-ICC than those with T-AS. XRF showed that the intensity ratio of Radium (Ra) to Thorium (Th) in non-tumorous liver tissue with T-ICC was significantly higher than that with T-AS. Furthermore, the mean (228)Ra/(232)Th radioactivity ratio at the time of death calculated was also significantly higher in T-ICC cases than in T-AS cases. These suggest that the metabolic behavior of radionuclides such as relocation and excretion, as well as the content of deposited radionuclides, is a major factor in determining the histological type of Thorotrast-induced liver tumors.

Unlabelled: Gankyrin (also known as PSMD10) is a liver oncoprotein that interacts with multiple proteins including MDM2 and accelerates degradation of the tumor suppressors p53 and Rb. We produced a monoclonal anti-gankyrin antibody and immunohistochemically assessed the clinicopathological significance of gankyrin overexpression in 43 specimens of human hepatocellular carcinoma (HCC). Specific cytoplasmic staining for gankyrin was observed in 62.8% (27/43) of HCCs, which was significantly associated with low TNM stage (P = 0.004), no capsular invasion (P = 0.018), no portal venous invasion (P = 0.008), and no intrahepatic metastasis (P = 0.012). The cumulative survival rate of patients with gankyrin-positive HCC was significantly higher than that with gankyrin-negative HCC (P = 0.037). p53 and MDM2 were positively stained by antibodies in 30.2% and 23.3%, respectively, of HCCs, but neither was inversely associated with gankyrin expression. In the Huh-7 human HCC cell line, overexpression of gankyrin up-regulated expression of insulin-like growth factor binding protein 5 (IGFBP-5), whereas suppression of gankyrin expression by siRNA down-regulated it. Supression of IGFBP-5 expression inhibited proliferation of Huh-7 cells as well as U-2 OS osteosarcoma cells. In HCC specimens, positive staining for IGFBP-5 was observed by immunohistochemistry in 41.9% (18/43), and the level of expression was significantly correlated with that of gankyrin (rho = 0.629, P < 0.001)., Conclusion: These results suggest that gankyrin plays an oncogenic role(s) mainly at the early stages of human hepatocarcinogenesis, and that IGFBP-5 inducible by gankyrin overexpression may be involved in it.

ATP-binding cassette (ABC) transporters comprise a superfamily of similar proteins involved in transmembrane transport of various substances. ABC transporter family members in the liver participate in bile formation and lipid metabolism. In order to assess whether peripheral blood leukocytes (PBL) are available as a surrogate for determination of the expression of ABC transporter genes in the liver, we compared ABC transporter gene expression levels in PBL with those in liver tissues from patients with hepatocellular carcinoma (HCC). We measured ABCA1, A2, B1-B4, C1 degrees C5, G1 and G2 gene expression levels in PBL, and cancerous and non-cancerous portions of liver from patients with hepatocellular carcinoma by means of real time reverse-transcription (RT)-PCR. We could not detect ABCC5 expression in any tissue of the liver. Close correlations between ABCA2, C1 and G1 in PBL and in non-tumor tissues of the liver were found. Compared with the non-tumor part, HCC tissue expressed lower levels of ABCA1, B4 and G2. We think monitoring of ABCA2, C1 and G1 gene expression levels in PBL will be useful for selection of anti-cancer agents and monitoring of drug resistance of HCC. Administration of chemotherapeutic agents which are substrates of ABCA1, B4 and G2 should be effective for the treatment of HCC.

Despite improvement in liver surgery, patient prognoses after surgical resection for hepatocellular carcinoma (HCC) remain unsatisfactory. One of the obstacles in managing post-operative recurrence is resistance to chemotherapy. We examined the effect of Cepharanthin (CEP), a natural alkaloid extracted from Stephania cepharantha Hayata, in overcoming P-glycoprotein (P-gp)-associated doxorubicine (DOX) resistance, using 2 DOX-resistant HCC cell lines, and their DOX-sensitive parental cell lines. P-gp expression in surgically removed HCC tumours was also examined. In the in vitro study, overexpression of P-gp in the resistant cells was confirmed by immunoblotting and RT-PCR. Drug sensitivity testing with MTT assay showed that co-administration of CEP significantly enhanced cytotoxicity of DOX, but only in resistant cells. Flow cytometric analysis revealed that CEP significantly increased intracellular DOX concentration by inhibiting DOX efflux. P-gp expression in 107 patients with HCC was examined retrospectively by immunohistochemistry. P-gp was overexpressed in the tumours of 36% of these patients, especially in well-differentiated tumours that are often insensitive to chemotherapy, supporting the use of P-gp modulation as a new chemotherapeutic approach. Multivariate logistic regression analysis revealed that serum alpha-fetoprotein level was inversely related to P-gp expression. Our data suggest that co-administration of CEP with DOX may potentiate the effect of chemotherapy on drug-resistant HCC.

We studied the alpha-radiation risks in patients who received injections of Thorotrast, an X-ray contrast medium used in Europe, Japan, and the United States from 1930 to 1955. Thorotrast was composed of thorium dioxide (ThO2) and Th-232, a naturally occurring radionuclide. Because the physical half-life of ThO2 is 14 billion years and Thorotrast is hardly eliminated from the body, tissues in which it was deposited are irradiated by alpha-radiation for the entire lifetime of the subject. The dosimetry of Thorotrast patients is very complicated, but currently its reliability is quite high compared with other irradiated populations. The major causes of the death of Thorotrast patients are liver cancer, liver cirrhosis, leukemia, and other cancers. Three histologies of liver cancer are found: cholangiocarcinoma, hepatocellular carcinoma, and angiosarcoma. Although cholangiocarcinoma is the most frequent, angiosarcoma is characteristic of alpha-radiation. Among blood neoplasms with a higher incidence of increase than the general population, erythroleukemia and myelodysplastic syndrome were remarkable. Thorotrast patients exhaled a high concentration of radon (Rn-220), a progeny of Th-232, but no excesses of lung cancer in the patients of Japan, Germany, and Denmark were reported. Mutation analyses of p53 genes and loss of heterozygosity (LOH) studies at 17p locus were performed to characterize the genetic changes in Thorotrast-induced liver tumors. Interestingly, LOH, supposedly corresponding to large deletions was not frequent; most mutations were transitions, also seen in tumors of the general population, suggesting that genetic changes of Thorotrast-induced cancers are mainly delayed mutations, and not the result of the direct effects of radiation.

To examine the role of the loss of heterozygosity (LOH) in hepatitis-related carcinogenesis, we performed a genome-wide scan of LOH in 44 tumors of hepatocellular carcinoma (HCC) using 216 microsatellite markers throughout all human chromosomes. A high frequency of LOH (>30% of informative cases) was observed at 33 loci on chromosome arms 4q, 6q, 8p, 8q, 9p, 9q, 13q, 16p, 16q, 17p, and 19p. LOH on 19p has not yet been reported, and that appears to be a new candidate in the search for tumor suppressor genes. High rates of LOH are correlated with hepatitis B virus (HBV) positivity, poorly differentiated tumors, vascular invasion, and intrahepatic metastasis (P <.0001). LOH on 13q and 16q occurred more frequently in HBV(+) patients (P <.0001), and LOH on 6q occurred more frequently in virus-negative patients (P <.001). The frequency of LOH on 4q and 13q was significantly lower in well-differentiated tumors than in moderately and poorly differentiated tumors (P <.01). In contrast, LOH on 6q was frequently detected in well-differentiated tumors compared with other histological subclasses (P <.001). Our results suggest that LOH on 6q may play an important role in the early stage of hepatocarcinogenesis in virus-negative patients, but different mechanisms might underlie the initial step to carcinogenesis in HBV(+) patients. LOH on 13q and 16q may play an essential role in the progression of HBV(+) tumors. Further studies of fine deletion mapping on chromosomes 13q and 16q are required to define the genomic segments on which putative tumor suppressor genes responsible for HBV(+) tumors exist.

Background: To determine whether a difference exists in the relative ability of power Doppler sonography and conventional color Doppler sonography to detect the intratumoral vasculature of hepatocellular carcinoma based on lesion size and location., Methods: Sixty patients with 88 hepatocellular carcinoma lesions that showed tumor staining on angiography and were enhanced on dynamic computed tomography were evaluated. Power Doppler sonography and color Doppler sonography were used to detect the intratumoral vasculature, and their sensitivity to blood flow was evaluated., Results: Power Doppler sonography showed a superior detection rate for lesions smaller than 2 cm and located 4-8 cm from the abdominal surface in the right hepatic lobe as compared with color Doppler sonography (p < 0.01). Neither power Doppler sonography nor color Doppler sonography depicted the intratumoral vasculature of lesions located more than 8 cm from the abdominal surface (n = 14). Both color Doppler imagings exhibited a low detection rate for lesions in the left hepatic lobe (n = 31, p < 0.01)., Conclusions: Power Doppler sonography should be applied in the evaluation of small or intermediate depth lesions because it is more sensitive to these lesions than color Doppler sonography, but it is not useful for left lobe and deep lesions.

Epidemiological studies have revealed that malignant tumors occur in the liver approximately 20 years after injection of Thorotrast. We investigated genetic changes in the TP53 gene (formerly known as p53) in malignant liver tumors related to Thorotrast to cast light on the mechanisms of alpha-particle carcinogenesis. A total of 19 autopsy cases of liver malignancies [11 hepatocellular carcinomas (HCC), 5 cholangiocellular carcinomas (CCC) and 3 angiosarcomas (AS)] were analyzed. Using archival tissues, loss of heterozygosity (LOH) at the 17p13 locus was analyzed. Then single-strand conformation polymorphism analysis and sequencing were performed to detect mutations in exons 5 to 8 of the TP53 gene. As a result, 15 cases were informative in terms of polymorphism, and 4 cases showed LOH (3 HCC and 1 AS). Eight cases showed 9 mutations in exons and 2 in introns: 7 transitions (6 HCC and 1 CCC), 2 transversions (1 HCC and 1 AS), and 2 deletions (2 HCC). The direct action of alpha particles is thought to result in relatively large deletions such as those detected by LOH. Therefore, the low frequency of such changes (27%) compared to point mutations (47%) suggests that the genetic changes in the TP53 gene in the liver tumors related to Thorotrast were not caused mainly by direct actions of alpha particles but rather by indirect effects that may have been due to cycles of necrosis and regeneration.

Owing to recent advances in imaging technology and radiologic intervention, survival rates in patients with hepatocellular carcinoma have improved markedly. However, such prolonged survival has resulted in an increase in extrahepatic metastases. Tc-99m (Sn)-N-pyridoxyl-5-methyltryptophan (Tc-99m PMT), developed for hepatobiliary scintigraphy, has been used to visualize extrahepatic metastases, with most related reports limited to osseous metastases. The authors report two cases of hepatocellular cancer presenting as a hypopharyngeal metastasis and intraperitoneal dissemination along the tract of a fine-needle biopsy. Lesions undetectable on planar imaging could be visualized by Tc-99m PMT SPECT.

The present study was designed to assess the chemosensitivity profile of freshly separated colorectal cancer cells and to screen effective agents for the design of new combination regimens. The DNA synthesis and chemosensitivity (% inhibition of DNA synthesis by the anticancer agent) were successfully assessed in 184 samples (107 primary and 77 metastatic or recurrent lesions) from 152 patients with colorectal cancer using an 3H-thymidine incorporation assay, and the correlations between these two measures and various clinicopathological factors were analysed. DNA synthesis was highest in nodal metastasis followed by malignant effusion, primary lesion, liver metastasis, and local recurrence. DNA synthesis liver metastasis and local recurrence were significantly lower than in other lesions. The results of the chemosensitivity assay are as follows: 5-FU seems to be the most beneficial for primary colorectal cancer; carboquone (CQ), etoposide (VP-16), 5-FU, and mitomycin-C (MMC) for nodal metastasis; CQ, cisplatin (CDDP), 5-FU, adriamycin (ADR) and VP-16 for malignant effusion; and VP-16, CDDP and CQ for liver metastasis. However, the present results showing the chemosensitivity profiles in different lesions suggest that regimens including 5-FU with VP-16 and CQ in addition to MMC or ADR may be applicable for all kinds of colorectal cancer lesions. These results demonstrated the heterogeneity in the chemosensitivity of colorectal cancer, which suggests not only the necessity of patient-specific chemotherapy dependent on the sensitivity assay, but also the usefulness of the present results in the choice of agents for widely applicable combination regimens for colorectal cancer.

Background/aims: The matrix metalloproteinase (MMP) family play important roles in the invasion of cancer cells by degrading the extracellular matrices. The current study was designed to determine the expression pattern of membrane-type matrix metalloproteinase-1 (MT1-MMP) in hepatocellular carcinomas and its participation in invasion potential., Methods: MT1-MMP mRNA expression was examined in 25 human hepatocellular carcinoma specimens using Northern blot, and the correlation to clinicopathological features was evaluated. In situ hybridization and immunohistochemistry were performed to study the localization and the cells responsible for the production., Results: Northern blot analysis revealed high levels of MT1-MMP mRNA expression in tumorous portions in all cases, whereas in non-tumorous portions moderate or faint expression was evident in 22/25 cases. In 21/25 cases, the expression levels in tumorous portion were higher than those in non-tumorous portion. In particular, hepatocellular carcinoma with capsule infiltration demonstrated significantly higher expression than those without (p<0.05). In situ hybridization and immunohistochemical study revealed MT1-MMP transcripts and proteins in cancer cells and stromal cells, respectively. MT1-MMP positive cells were preferentially observed in the invading border of tumor nests. The MMP-2 transcript showed a similar pattern to that of MT1-MMP by in situ hybridization., Conclusion: The present study showed that the MT1-MMP gene is strongly expressed in hepatocellular carcinoma cells and is involved in the invasion potential of hepatocellular carcinoma, and also that MT1-MMP may be one of the key molecules responsible for the invasion potential of hepatocellular carcinoma. Furthermore, the evidence suggests that MT1-MMP and MMP-2 cooperate in the process of cancer invasion.

We identified kan-1 complementary DNA (cDNA), the sequence of which is identical to bile acid CoA:amino acid N-acyltransferase (BAT), a liver enzyme that catalyzes the conjugation of bile acids with glycine or taurine. Kan-1(BAT) messenger RNA (mRNA) levels of the resected specimens obtained from 37 hepatocellular carcinoma (HCC) patients were studied in an attempt to evaluate prognostic significance in HCC patients after partial hepatectomy. Using Northern blot hybridization, kan-1(BAT) mRNA levels were quantified in tumorous and nontumorous tissues, and the ratio of the former to the latter was defined as the kan-1(BAT) ratio. Twelve patients had a kan-1(BAT) ratio < 0.5 (low kan-1[BAT] ratio), and 25 patients had a ratio >0.5 (high kan-1[BAT] ratio). The patients with a low kan-1(BAT) ratio demonstrated poorer survival than the patients with a high kan-1(BAT) ratio (P = .0013). The overall estimated hazard ratio for death in patients with a low kan-1(BAT) ratio was 68.05 according to a multivariate model (P = .0005). Thus, the kan-1(BAT) ratio may serve as a new molecular prognostic marker in HCC patients, following hepatic resection.

The prognosis for hepatocellular carcinoma (HCC) depends mainly on the clinicopathological characteristic regarding invasion and metastasis. In addition, another distinguishing feature of HCC is the high incidence of concomitant liver cirrhosis, in which the extracellular matrix proliferates markedly. Therefore, the present study was designed to investigate the molecules responsible for the invasion potential of HCC by focusing on matrix metalloproteinase (MMP) in particular, MMP-2 and MMP-9 and the corresponding tissue inhibitor of metalloproteinase (TIMP-2 and TIMP-1), because these enzymes participate in the degradation of the extracellular matrix including the basement membrane. Tumorous and adjacent nontumorous liver samples were obtained from 23 HCC patients who underwent a partial hepatectomy. In 16 of the 23 HCC samples, transcripts for MMP-9 were detected in the tumorous tissues, and 15 of 16 of these samples showed stronger expression in the tumorous tissues than in the nontumorous tissues. On the other hand, MMP-2 messenger RNA (mRNA) was detected in 18 of the 23 cases. Eight of these 18 cases showed more intense expression in the tumorous tissues than in the nontumorous tissues, whereas the expression levels were lower in the tumorous tissues than in the nontumorous tissues in 7 of 18 samples. With respect to the correlation between the clinicopathological features and mRNAs expression, it was found that the expression of MMP-9 mRNA in HCC with capsular infiltration was significantly higher than in HCC without capsular infiltration. HCC with capsular infiltration also tended to have a higher ratio of MMP-9 mRNA expression to TIMP-1 mRNA expression. In addition, the expression of MMP-2 mRNA in nontumorous cirrhotic tissues was significantly higher than in nontumorous tissues from patients with chronic hepatitis. Immunohistochemical examinations revealed that MMP-9 immunoreactivity was the most intense in the HCC cells, particularly in those cells in the marginal areas of the tumorous tissues. In conclusion, the present study shows that MMP-9 is closely participated in capsular infiltration in HCC.

Hepatocellular carcinoma (HCC) is a typical hypervascular tumor. However, the relationship between the vascularity of HCC and the expression of angiogenic factors has not been investigated. In addition, no detailed studies have examined the possible involvement of angiogenic factors in the grade of malignancy of HCC. The aim of this study was to determine which angiogenic factors regulate tumor angiogenesis and contribute to the invasive ability of liver tumors, especially of HCC. Northern blot analysis was used to examine the transcriptional expression of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (FGF), and acidic FGF in resected surgical specimens (20 HCC and 9 metastatic liver tumors). Correlations between messenger RNA (mRNA) expression and arteriographic findings, as well as histopathological findings, were evaluated. Immunohistochemistry was performed to identify the localization of cells expressing VEGF in HCC. Higher levels of VEGF mRNA were observed in 12 of 20 HCC and 2 of 9 metastatic liver tumors than in corresponding nontumorous tissues. The degree of VEGF mRNA expression was significantly correlated with the intensity of tumor staining in angiograms (P<.01). On immunohistochemical observation, VEGF protein was intensely detected in HCC cells. Furthermore, basic FGF mRNA was detected in 9 of 20 HCC and was related to the capsular infiltration of cancer cells (P<.05). In contrast, no significant difference was observed in the very low levels of acidic FGF mRNA found in the tumorous and nontumorous portions of the liver. In conclusion, these results suggest that VEGF contributes to angiogenesis of liver tumors, whereas basic FGF may be involved in the invasion of HCC into the surrounding tissues.

A cloned human hepatoma cell line (HH2-1) produced and formed collagen fibers in vitro. The relative rate of collagen synthesis by the cells was increased with an enhancement of the cell density. An analysis of the components of the collagen using sodium dodecyl sulfate-polyacrylamide gel electrophoresis revealed that the cells synthesized interstitial collagen, types I and III, and other collagenous proteins. Thus, human hepatoma cells may play an important role in the formation of stromal collagen in the tumor.