An in vivo screening system to identify tumorigenic genes.

Screening for oncogenes has mostly been performed by in vitro transformation assays. However, some oncogenes might not exhibit their transforming activities in vitro unless putative essential factors from in vivo microenvironments are adequately supplied. Here, we have developed an in vivo screening system that evaluates the tumorigenicity of target genes. This system uses a retroviral high-efficiency gene transfer technique, a large collection of human cDNA clones corresponding to ~70% of human genes and a luciferase-expressing immortalized mouse mammary epithelial cell line (NMuMG-luc). From 845 genes that were highly expressed in human breast cancer cell lines, we focused on 205 genes encoding membrane proteins and/or kinases as that had the greater possibility of being oncogenes or drug targets. The 205 genes were divided into five subgroups, each containing 34-43 genes, and then introduced them into NMuMG-luc cells. These cells were subcutaneously injected into nude mice and monitored for tumor development by in vivo imaging. Tumors were observed in three subgroups. Using DNA microarray analyses and individual tumorigenic assays, we found that three genes, ADORA2B, PRKACB and LPAR3, were tumorigenic. ADORA2B and LPAR3 encode G-protein-coupled receptors and PRKACB encodes a protein kinase A catalytic subunit. Cells overexpressing ADORA2B, LPAR3 or PRKACB did not show transforming phenotypes in vitro, suggesting that transformation by these genes requires in vivo microenvironments. In addition, several clinical data sets, including one for breast cancer, showed that the expression of these genes correlated with lower overall survival rate.

Valuable antiviral therapeutic options for the treatment of chronic hepatitis C patients with thrombocytopenia.

Thrombocytopenia in patients with chronic hepatitis C may represent an obstacle for the initiation of antiviral treatment. The aim of this study was to evaluate factors predictive of successful pegylated interferon (PEG-IFN) α2b and ribavirin (RBV) treatment for patients with thrombocytopenia with no history of splenectomy or partial splenic embolization. One hundred and fifty-one chronic hepatitis C patients (genotype 1: n = 110, genotype 2: n = 41) with TCP (<100 × 10(9) /L) at baseline were enrolled. Pretreatment variables included interleukin 28B (IL28B) genotype (rs8099917) and homoeostasis model assessment of insulin resistance score (HOMA-IR). The kinetics of haemoglobin and platelets according to the inosine triphosphatase (ITPA) genotype (rs1127354) were investigated. Sustained virological response (SVR) was significantly more frequent in hepatitis C virus (HCV) genotype 2 (65.9%) than in genotype 1 (34.5%) patients (P < 0.0001). Multiple logistic regression analysis of HCV genotype 1 extracted IL28B TT genotype [odds ratio (OR) 5.97, P = 0.006] and HOMA-IR <2.5 (OR 7.14, P = 0.0016) as significant independent pretreatment predictors of SVR. The analyses of HCV genotype 2 showed that HOMA-IR was significantly related to SVR, but IL28B genotype was not. Patients with ITPA CC genotype showed a significant haemoglobin reduction and lower degree of platelets decrease than those with ITPA CA/AA genotypes. The most common reason for premature discontinuation of treatment was the development of hepatocellular carcinoma (n = 8, 5.3%). In conclusion, HOMA-IR is a useful predictor of SVR for patients with thrombocytopenia infected with HCV genotype 1 or 2 treated with PEG-IFNα2b and RBV. The inclusion of IL28B, ITPA genotypes and HOMA-IR adds valuable therapeutic information.

Serum pepsinogen and Helicobacter pylori infection--a Japanese population study.

The decreased ratio of serum pepsinogen (PG) I and II has good correlation with the presence of atrophic gastritis. A total of 1,540 residents aged 30-89 years were enrolled into this study to investigate which serum PG level of residents with Helicobacter pylori infection would represent an adjunct to the diagnosis and progression of atrophic gastritis. All participants received esophagogastroduodenoscopy. Serum antibody to H. pylori (anti-H. pylori) was measured by an enzyme-linked immunosorbent assay (ELISA). Serological atrophic gastritis was defined as serum PG I isozyme level ≤70 ng/ml and a PG I/II ratio of ≤3.0. Of the 1,540 participants, 923 (59.9%) were positive for anti-H. pylori. Serological atrophic gastritis was found significantly more often in anti-H. pylori-positive participants (40.8%) than in anti-H. pylori-negative participants (7.9%) (p ≤ 0.0001). The endoscopic findings of anti-H. pylori-positive participants with serological atrophic gastritis were significantly more frequent by 4.06 times for atrophic gastritis (p ≤ 0.0001) than anti-H. pylori-negative participants without serological atrophic gastritis. Eight anti-H. pylori-positive participants were diagnosed with gastric cancer, but no cancer was found in anti-H. pylori-negative participants without serological atrophic gastritis. Serum PG testing is clinically useful for the prediction of gastric lesions in H. pylori-infected persons.

A comparative study of the diagnostic accuracy of ELISA systems for the detection of anti-neutrophil cytoplasm antibodies available in Japan and Europe.

OBJECTIVES: Primary systemic vasculitis associated with anti-neutrophil cytoplasm antibodies (ANCA) differs in its frequency and clinical expression between Japan and Europe. We sought to ascertain whether such differences arise from the performance of enzyme-linked immunosorbent assays (ELISAs) for ANCA. METHODS: Plasma samples from 64 consecutive Japanese patients with a clinical and histological diagnosis of primary systemic vasculitis including microscopic polyangiitis (MPA; n=52), Churg-Strauss syndrome (CSS; n=1), and Wegener's granulomatosis (WG; n=11), or those from disease controls with non-vasculitic glomerulonephritis (n=54) and healthy controls (n=55) were tested for the presence of myeloperoxidase (MPO) by ELISAs available in Japan (Nipro and MBL) and compared with those in Europe (Wieslab). The sensitivity and specificity were calculated for each ELISA, and its diagnostic performance was assessed by receiver operating characteristic curve analysis. RESULTS: The sensitivity and specificity of either MPO-ANCA assays for a diagnosis of MPA were 90.4% and 98.2% (Nipro), 88.2% and 96.3% (MBL), and 86.5% and 99.1% (Wieslab). The overall diagnostic performance, assessed as the area under curve of the MPO-ANCA ELISAs for MPA were 0.946+/-0.022 (Nipro), 0.970+/-0.017 (MBL), and 0.971+/-0.017 (Wieslab), while that of PR3-ANCA ELISAs for WG were 0.986+/-0.025 (Nipro), 0.993+/-0.017 (MBL), and 0.916+/-0.059 (Wieslab). CONCLUSIONS: The MPO-ANCA ELISAs commercially available in Japan exhibited high sensitivity and specificity for the diagnosis of ANCA-associated vasculitides and provided similar diagnostic value to those in Europe. These results facilitate further international comparison of ANCA-associated vasculitides between Japanese and European populations.

Possible involvement of mast cells in renal fibrosis in patients with IgA nephropathy.

OBJECTIVE: The objective of the present study is to investigate whether human mast cells (MC) contribute to renal damage through local activation of the renin-angiotensin system, by assessing their numbers in renal biopsy specimens from patients with IgA nephropathy (IgAN) or minimal change nephrotic syndrome (MCNS). METHODS: In patients with IgAN and MCNS, the numbers of tryptase-positive MC (MC(T)) and MC positive for both tryptase and chymase (MC(TC)) were examined histopathologically. Serum creatinine level, mean blood pressure and the severity of glomerular and tubulointerstitial lesions were also determined. RESULTS: MC(TC) numbers differed between IgAN patients and MCNS patients. IgAN patients had more MC(TC) than MC(T). MC were found around but not in the conglomerate of the AngiotensinII (AngII)-positive cells. In the IgAN patients with the most severe pathology, the number of AngII-positive cells was correlated with that of MC(TC) and MC(T). CONCLUSION: Chymase-dependent AngII synthesis due to human MC may be involved in the inflammatory and fibrotic processes of IgAN.

Pathological features of mucinous carcinoma of the breast are favourable for breast-conserving therapy.

AIM: The effectiveness of breast-conserving therapy for mucinous carcinoma has not been well documented. We examined clinical and pathological features of cases to determine whether patients with mucinous carcinoma were suitable candidates for this treatment. METHOD: Cases of pure type (n=52) and mixed type (n=24) mucinous carcinomas were reviewed with emphasis on the risk factors associated with local recurrences after breast-conserving therapy. RESULTS: Large pure mucinous carcinomas had a low incidence of extensive intraductal spreading (EIS). An inverse correlation existed between the incidence of EIS and tumour size (P<0.05). Comedo type EIS was infrequent (11%) in pure mucinous carcinoma. Incidences of lymphatic vessel invasion (4%) and nodal involvement (4%) were lower in pure mucinous carcinoma than in mixed carcinoma (P<0.05). No nodal involvement occurred in patients with pure mucinous carcinoma less than 3 cm in diameter. CONCLUSIONS: Patients with pure mucinous carcinomas, except those invading the local skin, are suitable candidates for breast-conserving therapy. Most pure mucinous carcinomas, including a large tumour up to 5 cm in diameter, can be treated with this therapy.

Axillary lymph node metastases in patients with small carcinomas of the breast: is accurate prediction possible?

OBJECTIVES: To find out whether macroscopic classification of the tumour margin is predictive of axillary lymph node metastases and to identify a combination of clinical and pathological findings by which axillary node status can be predicted accurately in small carcinomas (T1) of the breast. DESIGN: Retrospective study. SETTING: Municipal referral centre, Japan. SUBJECTS: All 1003 patients with T1 invasive carcinoma of the breast who had axillary lymph node dissection between January 1970 and December 1996 as part of their treatment. MAIN OUTCOME MEASURES: The association between the incidence of axillary lymph node metastases and 10 clinical and pathological factors (age, palpability and size of tumour, macroscopic classification of tumour margin, clinical axillary status, radiating spiculation on a mammogram, histological type, lymphatic invasion, oestrogen and progesterone receptor status) were analysed. RESULTS: Clinical axillary node status, macroscopic classification of tumour margin, lymphatic invasion, and age of the patient were significant predictors of axillary lymph node metastases (p < 0.01 in each case). Among 47 patients aged 65 or more whose tumours had well-defined margins and with a clinical N0 status in the axillae, the incidence of histological axillary lymph node metastasis was only 6% (n = 3) whereas it was 65% in 57 patients with tumours of ill-defined margins whose axillae were N1 or N2. CONCLUSIONS: Macroscopic classification of tumour margins is an independent predictor of axillary lymph node metastases for patients with small carcinomas of the breast. However, even with combinations of the examined predictors of axillary node metastases, the subgroup of patients at minimal risk of metastasis was less than 5% in T1 breast cancer, whereas three-quarters of the patients had clear axillary lymph nodes. Most patients with T1 breast cancer will need surgical staging of the axillae by methods such as sentinel node biopsy.

Enhancement of brush border membrane peptidase activity in rat jejunum induced by starvation.

Conflicting results have been obtained in previous studies concerning the adaptation of intestinal blush border membrane enzymes to starvation. This study was designed to clarity the changes in these enzymes under starvation conditions, using a molecular biological approach. Sprague-Dawley rats were starved or given total parenteral nutrition (TPN) for 5 days. Rats allowed free access to food were used as controls. Changes in the activity and expression of jejunal brush border membrane enzymes were compared between three groups. In the starved group, aminopeptidase N and dipeptidyl peptidase IV activity was significantly elevated to 177% and 166%, respectively, of control values. In contrast, sucrase and maltase activity was significantly decreased. The activity of these peptidases also tended to be increased at the renal brush border membrane. Up-regulation of peptidase activity was not evident in the TPN group. Western and Northern blot analysis revealed that the changes in aminopeptidase N activity were attributable to increases in the protein and mRNA level. The activity and expression of brush border membrane peptidases in rat jejunum is up-regulated during starvation, and these changes are considered to be an effect of whole-body malnourishment, rather than an absence of luminal nutrition.

Efficacy of oral adsorbent for treatment of peristomal fistula associated with Crohn's disease.

Perianal fistulae are frequently seen complications in Crohn's disease. Although surgical procedures such as Seton's method have been devised, many patients still suffer from fistulae that are resistant to conventional therapy. We administered oral adsorbent to a patient with disease Crohn's who had a complicated peristomal fistula that did not improve with conventional therapy. Six grams of oral adsorbent (AST-120) were added daily to a regimen of elemental diet therapy and prednisolone. The fistula gradually decreased in size after the administration of the oral adsorbent, and had healed completely after 40 days' treatment. There were no side effects from the oral adsorbent. This case report suggests that oral adsorbent is an effective treatment for peristomal fistula associated with Crohn's disease.

Positive inotropic effects of adrenomedullin on rat papillary muscle.

Adrenomedullin is a peptide recently isolated from pheochromocytoma that has vasorelaxant and long-lasting hypotensive activities. Plasma levels of adrenomedullin are elevated in patients with congestive heart failure, but the effects of adrenomedullin on the cardiac function are unclear. We, thus, investigated the effects of adrenomedullin on the contraction of rat papillary muscles. We measured the isometric tension and cAMP contents of isolated rat papillary muscles. Adrenomedullin exhibited concentration-dependent inotropic effects. Adrenomedullin also significantly increased intracellular contents of cAMP. Addition of the calcitonin gene-related peptide (CGRP) receptor antagonist inhibited both contractile force and cAMP generation of papillary muscles stimulated by adrenomedullin. The adrenomedullin-induced inotropic effect was further increased in the presence of the phosphodiesterase inhibitor, 3-isobutyl-1-methyl-xanthine (IBMX), while the effect was significantly suppressed by KT5720 and Rp-8-bromoadenosine-3',5'-cyclic monophosphorothioate (Rp-8-Br-cAMPS), protein kinase A inhibitors. These results indicate that adrenomedullin has positive inotropic effects on the heart, at least partially through a cAMP-dependent pathway.

Clinical importance of n-3 fatty acid-rich diet and nutritional education for the maintenance of remission in Crohn's disease.

Elemental diet (ED) therapy has been established as primary therapy for Crohn's disease, and home enteral nutrition (HEN) has been reported to control relapse at a dose of more than 30kcal/kg of ideal body weight. However, a decrease in ED compliance with long-term use is becoming problem. We developed an n-3 fatty acid-rich diet and carried out nutritional education specifically for Crohn's disease patients using HEN to facilitate compliance and to improve their nutritional status. After the introduction of this n-3 rich diet, disease activity was not altered, and nutritional status, especially serum n-3 fatty acid levels, improved. The remission periods in patients with poor compliance seemed to be prolonged by the nutritional education. Thus, a n-3 rich diet in combination with nutritional education specific for Crohn's disease patients is very important for the in maintenance of high compliance and for maintaining nutritional balance.

Direct detection of apoptotic cells in peripheral blood from highly pathogenic SHIV-inoculated monkey.

Apoptosis in peripheral blood leukocytes (PBL) has been estimated by the enhancement of spontaneous apoptosis after in vitro culture, because apoptotic cells have not been observed directly in freshly isolated PBL in the course of HIV/AIDS. In monkeys infected with a highly pathogenic simian/human immunodeficiency virus (SHIV), which corresponds to rapid progressors of HIV infection, a high frequency of apoptotic cells was directly detected in fresh PBL by electron-microscopic studies. Peripheral blood apoptosis transiently occurred after intense plasma viremia, and peaking at 3 weeks postinfection; occurrence was not limited specifically to lymphocytes, but also occurred in other types of leukocytes. Apoptosis in peripheral lymph nodes was also detected following intense plasma viremia. However, the in vivo apoptosis was not detected in nonpathogenic SHIV-infected monkeys that showed no cell loss. Thus, we directly showed the apoptosis of PBL, which might be associated with pathogenic SHIV produced during the time of plasma viremia.

Tubular carcinoma of the breast: a histologic subtype indicative of breast-conserving therapy.

We reviewed the clinical and pathologic features of pure tubular carcinoma of the breast with particular emphasis on the reported risk factors associated with local recurrences and survival following breast-conserving therapy. Of 1653 cases of invasive breast cancer, 12 (0.7%) were identified as pure tubular carcinoma. Clinical/pathologic features of pure tubular carcinoma were compared with those of T1 invasive carcinoma of all other histologic types (T1 IC). Of the 12 patients with pure tubular carcinoma (median tumor diameter 1.4 cm; range 0.5-3.0 cm), a multicentric association was identified in one patient while a multifocal association was seen in two. One patient had nodal metastatic disease out of the ten who underwent axillary dissection. No lymphatic vessel invasion was identified in any tumors (P < 0.1 vs T1 IC). In addition, extensive intraductal spread was not present in any tumors (P < 0.05 vs T1 IC). This study shows that patients with pure tubular carcinoma are appropriate candidates for breast-conserving therapy based on the clinical/ pathologic features. When a multifocal association is suspected preoperatively, either a wide local excision or a quadrantectomy which includes other lesions is thus recommended.

IL-12, IFN-gamma, and TNF-alpha released from mononuclear cells inhibit the spread of varicella-zoster virus at an early stage of varicella.

The activity of mononuclear cells to inhibit plaque formation of varicella-zoster virus (VZV) was investigated by an in vitro infectious center assay. Peripheral blood mononuclear cells (PBMC) inhibited VZV plaque formation by co-cultivation with VZV-infected fibroblasts. As compared to mononuclear cells from normal individuals, mononuclear cells from umbilical cord blood and from patients receiving corticosteroids showed a significant decrease in the ability to inhibit viral replication. This ability was significantly increased for mononuclear cells collected during the acute phase of varicella. PBMC obtained from patients in the acute phase of varicella produced significantly higher amounts of interferon (IFN)-gamma, tumor necrosis factor (TNF)-alpha, and interleukin (IL)-12 in the supernatant compared with those of healthy individuals. These data suggest that the cytokines have an important role in the inhibition of the spread of VZV at an early stage of varicella. Th1 type adaptive immunity might play a major role in VZV infection.

Ultrastructural evaluation of apoptosis induced by Helicobacter pylori infection in human gastric mucosa: novel remarks on lamina propria mucosae.

It has been considered that Helicobacter pylori (H. pylori) infection is a major cause of human gastritis and gastroduodenal ulcers (G-DU). Many investigations of the relationship between H. pylori and apoptosis have been reported recently. However, these studies focused mostly on epithelium, using the TUNEL method. In the present study, we evaluated by electron microscopy the occurrence of apoptosis in the mesenchymal cells of lamina propria mucosae infected with H. pylori. Gastric biopsy specimens from 37 H. pylori-infected G-DU patients and 8 noninfected volunteers were examined with both light and electron microscopy and analyzed by the TUNEL method. The TUNEL method showed no significant difference between H. pylori-infected and noninfected cases. In contrast, electron microscopy revealed significant numbers of apototic fibroblasts and smooth muscle cells in H. pylori-infected lamina propria mucosae, with a diminished number of collagen fibers in surrounding areas. These areas showed edematous changes histopathologically. These results indicated that H. pylori infection induces apoptosis of fibroblasts and smooth muscle cells in lamina propria, with decrease in the numbers of collagen fibers, suggesting that these alterations may be affected by exaggerate acid secretion, decrease mucus protecting factors, and result in ulcer formation.

Stomal recurrence invading the cervicothoracic esophagus and upper mediastinum: resectability and the creation of a safe anterior mediastinal tracheostoma.

Surgical salvage for stomal recurrence is a for midable problem for head and neck surgeons. The two factors of considerable significance are resectability and establishment of a safe anterior mediastinal tracheostoma. A case of stomal recurrence invading the cervicothoracic esophagus and upper mediastinum is presented. Total esophagectomy and upper mediastinal dissection was performed. The esophagus was reconstructed immediately with a pedicled gastric flap. The omentum on the gastric pedicle was wrapped around the trachea to reduce the likelihood of erosion into the great vessels and to supplement the lateral blood supply to the trachea. No serious postoperative complications were observed. We believe that the total esophagectomy improved the resectability, and that the bulk of the gastric pedicle and the use of the omentum prevented significant postoperative complications associated with an anterior mediastinal tracheostoma.

Histopathological Predictors of Axillary Lymph Node Metastases in Patients with Breast Cancer.

BACKGROUND: A tumor 30 mm or less in diameter is a standard candidate for breast conserving surgery (BCS) in Japan. Axillary lymph node metastases (ALNM) is the most important prognostic factor for survival in patients with breast cancer, but the role of axillary node dissection has been controversial. Histopathological predictive factors of axillary lymph node involvement have not been established. The purpose of this study was to determine the association between the incidence of ALNM and histopathological factors by univariate and multivariate analysis METHODS: Sixty-five patients with noninvasive ductal carcinoma, and 993 patients with tumors 30 mm or less in diameter who underwent axillary dissection between 1988 and 1997 at our institute were reviewed. The association between ALNM and 13 histopathological factors (size, age, histological subtype, histological invasiveness, lymphatic invasion, vascular invasion, macroscopic classification, histological daughter mass, ductal spread, ER, PgR, p-53, and c-erbB-2) were analyzed by univariate and, when significant, by multivariate analysis. RESULTS: Only one patient with noninvasive ductal carcinoma had ALNM, and 33.1% of 993 patients with a tumor 30 mm or less in size had ALNM. Multivariate analysis identified six factors as independent predictors for ALNM: lymphatic invasion, size, histological invasiveness, macroscopic classification, age and histological daughter mass. CONCLUSION: Axillary lymph node dissection can be omitted in patients with noninvasive ductal carcinoma. Histopathological features of tumors 30 mm or less in diameter can be used to estimate the risk of ALNM, and routine axillary node dissection might be spared in selected patients at minimal risk of ALNM, if the treatment decision is not influenced by lymph node status, such as in elderly patients.

Medium-chain triglycerides modulate ileitis induced by trinitrobenzene sulfonic acid.

BACKGROUND: It is important to develop an appropriate animal model for further investigation into inflammatory bowel disease (IBD). We therefore investigated a trinitrobenzene sulfonic acid (TNBS) ileitis model. Dietary fat in Crohn's disease is still a controversial risk factor for IBD. We therefore also studied the effects of medium-chain triglycerides (MCT) and long-chain triglycerides (LCT) on TNBS ileitis. METHODS AND RESULTS: An intraileal injection of TNBS induced ulceration and inflammation with thickening of the intestinal wall, which were characterized histologically by infiltration of polymorphic nuclear leucocytes and by granuloma formation. The mucosal damage score and serum sialic acid levels reached their highest 7 days after the TNBS injection and then gradually decreased. The mucosal damage series in the MCT group was significantly lower than in the LCT group, and levels of tumour necrosis factor-alpha (TNF-alpha) and leukotriene B4 (LTB4) tended to be lower in the MCT group. CONCLUSIONS: These results suggested that TNBS enteritis might be useful as an IBD animal model and that MCT modulates intestinal inflammation and is less damaging than LCT.

Changes in serum diamine oxidase activity during chemotherapy in patients with hematological malignancies.

Serum diamine oxidase (DAO) activity is very low, but is considered to reflect quantitative changes in small intestinal mass. Therefore, we measured DAO activity during chemotherapy in patients with hematological malignancies in order to evaluate mucosal injury. DAO activity decreased from 1-3 weeks after chemotherapy but returned to initial levels after 4 weeks. As the dosage of anti-cancer drugs increased, DAO activity decreased more, but its activity was not related to other parameters. These findings suggest that serum DAO could be used as an indicator of mucosal injury during chemotherapy.

Suppression of arachidonic acid cascade-mediated apoptosis in aflatoxin B1-induced rat hepatoma cells by glucocorticoids.

It has been shown that hypophysectomy protects aflatoxin B1 (AFB1) hepatocarcinogenesis and the prevention of apoptosis is a critical process for tumorigenesis. In this paper, we analyzed the cell death of AFB1-induced rat hepatoma Kagura-2 (K2) cells elicited by an estrogen antagonist, tamoxifen (TAM), and transforming growth factor-beta1 (TGF-beta1) to elucidate the function of endocrine factors in AFB1 hepatocarcinogenesis. TAM and TGF-beta1 induced a typical apoptosis in K2 cells. The apoptotic cell death was efficiently suppressed by glucocorticoids (GCs), but not by other steroid compounds including 17beta-estradiol (E2). Cyclo-oxygenase (COX) inhibitors such as aspirin (ASP) and indomethacin (IND) also inhibited the apoptosis, while inhibitory effects of general lipoxygenase (LOX) inhibitors such as nordihydroguaiaretic acid (NDGA) and 5,8,11-eicosatrienoic acid (ETI) were not observed. TAM and TGF-beta1 enhanced the release of [3H]arachidonic acid (AA) from pre-labeled K2 cells, which was inhibited by dexamethasone (DEX). Furthermore, cytosolic phospholipase A2 (cPLA2) activity in K2 cells treated with TAM for 2 h was higher than that in the control. Prostaglandin J2 (PGJ2) and delta12-PGJ2, AA metabolites formed in the COX pathway, induced K2 cell death. These results suggest that AA metabolites are involved in apoptotic K2 cell death elicited by TAM and TGF-beta1, and GCs could act as a tumor promoter in AFB1 hepatocarcinogenesis through the prevention of apoptosis induced by AA metabolites formed in vivo.