Increasing insulin resistance is associated with increased severity and prevalence of gastro-oesophageal reflux disease.

BACKGROUND: The diagnosis of gastro-oesophageal reflux disease (GERD) is based on reflux symptoms. Although metabolic syndrome has been linked to erosive oesophagitis (EO), the impact of insulin resistance, the core of the metabolic syndrome, on reflux symptoms remains to be elucidated. AIM: To assess the effects of insulin resistance on GERD, including both endoscopic findings and symptoms. METHODS: A total of 743 sonographic noncirrhotic adult subjects, who underwent an upper gastrointestinal endoscopic examination, completed a gastro-oesophageal reflux questionnaire and had available fasting insulin data were included. Endoscopic findings were classified according to the Los Angeles classification. Homeostatic model assessment-insulin resistance (HOMA-IR) index was used to evaluate the status of insulin resistance. Univariate and multivariate approaches were used to evaluate the associations between insulin resistance and GERD. RESULTS: Older age, male gender, smoking and alcohol consumption increased the prevalence of EO, but not GERD symptoms. A large waist circumference, high fasting blood glucose levels and high number of metabolic syndrome components were associated with increased prevalence of both EO and GERD symptoms, while high blood pressure was associated with increased prevalence of EO only. Moreover, higher scores in the gastro-oesophageal reflux questionnaire were associated with higher HOMA-IR index, and higher HOMA-IR index was associated with increased prevalence of EO (adjusted odds ratio 1.14, 95% CI 1.03-1.26, P = 0.012). CONCLUSIONS: Our findings demonstrate clear associations between insulin resistance, metabolic syndrome and GERD. Whether reducing insulin resistance may improve GERD symptoms or EO deserves prospective study.

Cloning and functional characterization of the HRASLS2 gene.

The HRAS-like suppressor 2 (HRASLS2) gene belongs to the H-REV107 gene family involved in the regulation of cell growth and differentiation. HRASLS2 is expressed at high levels in normal tissues of the small intestine, kidney, and trachea. We cloned HRASLS2 cDNA from human SW480 colon cancer cells. Most wild-type, and some N- and C-terminal truncated HRASLS2 (HRASLS2DeltaNDeltaC) were expressed as a granular pattern located at perinuclear region in HtTA cervical cancer cells, while truncation at the C-terminus only (HRASLS2DeltaC) resulted in a diffuse pattern. Wild-type HRASLS2 significantly suppressed colony formation of HeLa and HCT116 cells. HRASLS2DeltaNDeltaC significantly inhibited colony formation of HCT116 cells, but HRASLS2DeltaC did not affect cell growth. HRASLS2 suppressed the RAS-GTP levels and total RAS protein by 44% and 25%, respectively in HtTA cells; however, the suppression was not observed in truncated HRASLS2 variants. In conclusion, the HRASLS2 protein suppressed growth and RAS activities of cancer cells, and the C-terminal hydrophobic domain appeared to be indispensable for both activities.

Eosinophilic gastroenteritis presenting as relapsing severe abdominal pain and enteropathy with protein loss.

Eosinophilic gastroenteritis (EG) is an uncommon gastrointestinal tract disease, and diagnosis can be difficult. A combination of acute or recurrent abdominal pain with peripheral hypereosinophilia suggests the diagnosis. Surgery in patients with these features might therefore be avoided. Physicians must maintain a high index of suspicion and a working knowledge of the natural history of EG in order to establish the proper diagnosis. We present the case of a young man with EG who presented with relapsing severe abdominal pain and enteropathy with protein loss.

Hepatitis B virus reactivation in breast cancer patients undergoing cytotoxic chemotherapy and the role of preemptive lamivudine administration.

BACKGROUND: Recent data suggest that hepatitis B virus (HBV) reactivation develops in 41% of breast cancer (BC) patients carrying HBV after chemotherapy. Our study aimed to determine the role of preemptive use of lamivudine in BC patients undergoing chemotherapy. PATIENTS AND METHODS: The test group consisted of 11 female patients with BC who were seropositive for hepatitis B surface antigen (HBsAg). Of these, 10 patients were treated in an adjuvant setting and one for metastatic disease. Lamivudine was given from the start of chemotherapy and was maintained until 1 month after the last infusion of chemotherapy. The control group consisted of nine historical BC patients carrying HBV and received similar systemic chemotherapy without preemptive lamivudine. Variables including HBsAg, HBV envelope antigen, anti-HBV envelope antibody, serial serum alanine transaminase (ALT), quantitative HBV viral DNA analysis, and HBV-DNA precore promoter and precore sequence were monitored. Test for emergence of mutant strains, notably nucleotide 550, was performed 6 months after the completion of chemotherapy. RESULTS: All patients tolerated lamivudine well without development of evident HBV reactivation or overt hepatitis. Serum ALT remained unchanged without rebound hepatitis after cessation of chemotherapy and withdrawal of lamivudine. No emergence of lamivudine-selective resistant strain (so-called tyrosine-methionine-aspartate-aspartate mutations) was observed. CONCLUSIONS: Our results encourage preemptive use of lamivudine for prevention of HBV reactivation in patients who need short-term chemotherapy.

Strangulated transmesosigmoid hernia: CT diagnosis.

We present a rare case of strangulated closed loop small bowel obstruction secondary to a transmesosigmoid hernia to emphasize the diagnostic role of computed tomography in patients with no history of previous surgery. The characteristic computed tomographic features showed a cluster of dilated, fluid-filled, U- and C-shaped loops of small bowel entrapped the left posterior and lateral to the sigmoid colon through a defect in the mesosigmoid, which caused anterior and medial displacement of the sigmoid colon.

Restoration of immunity and reactivation of hepatitis B virus after immunosuppressive therapy in a patient with severe aplastic anaemia.

We recently treated a patient with severe aplastic anaemia (SAA) who also had chronic hepatitis B virus (HBV) infection. The HBV serological status at the time of diagnosis of SAA was HBsAg(+) and HBeAg(+). Subsequent analysis of the precore region of HBV DNA showed wild-type. He received anti-thymocyte globulin (ATG) and cyclosporin A (CsA) therapy twice. After each course of ATG infusion and during CsA therapy he developed lymphopenia for 1 and 2.5 months, respectively. His serum alanine aminotransferase (ALT) became normalized during the period of lymphopenia, but the serum HBV viral load increased. When his peripheral lymphocytes count recovered, his ALT became elevated again. Lamivudine was effective to normalize his elevated ALT and suppress viral replication. The phenomenon observed in this case supports the prevailing notion that hepatitis B flare-up in HBV carriers after chemotherapy is caused by an immune-mediated mechanism. Meanwhile, this is the first documented case of SAA who developed HBV reactivation upon recovery of lymphopenia after immunosuppressive therapy. This also highlights the necessity of pre-emptive therapy with lamivudine in SAA/HBsAg(+) patients to receive immunosuppressive therapy with ATG/CsA.

RARRES3 expression positively correlated to tumour differentiation in tissues of colorectal adenocarcinoma.

RARRES3 is a retinoid-inducible class II tumour-suppressor gene. This study analysed the expression of RARRES3 protein in normal, adenoma and carcinoma tissues of the colorectum and its correlation with tumour differentiation. The expression of RARRES3 protein in 151 paraffin-embedded colorectal tissues (11 distal normal mucosa, 20 adenoma and 120 colorectal adenocarcinoma) was determined by immunohistochemistry. RARRES3 protein was expressed in all 11 distal normal, 120 adjacent normal and 20 adenoma tissues. In distal normal tissues, RARRES3 protein was expressed at the highest levels in differentiated mucosal epithelial cells. Among 120 carcinoma tissues, RARRES3 protein was detected in 97.6% (40 out of 41), 79.4% (54 out of 68) and 17.3% (three out of 11) of well-, moderately and poorly differentiated tumours, respectively. The expression of RARRES3 protein was positively correlated to tumour differentiation (test for trend, P<0.0001). Also, levels of RARRES3 protein were found to be higher in the normal tissues adjacent to 14.6% (six out of 41), 51.5% (35 out of 68), and 90.1% (10 out of 11) of well-, moderately and poorly differentiated tumours, respectively. The decreases in tumour differentiation and RARRES3 expression were significantly correlated compared to the adjacent normal tissues (test for trend, P<0.0001). The prognostic implication of RARRES3 protein expression was studied in 107 tumour, and no statistical difference in survival was observed. The expression of RARRES3 protein was positively correlated to cellular differentiation of normal and adenocarcinoma tissues of the colorectum, which supports the role of RARRES3 in normal and malignant epithelial differentiation of colorectum. RARRES3 expression was decreased only in carcinoma tissue, which suggests that altered RARRES3 expression occurs late in colorectal carcinogenesis.

Prospective study of Helicobacter pylori eradication therapy in stage I(E) high-grade mucosa-associated lymphoid tissue lymphoma of the stomach.

PURPOSE: High-grade mucosa-associated lymphoid tissue (MALT) lymphomas of the stomach are generally believed to be Helicobacter pylori-independent, autonomously growing tumors. However, anecdotal cases of regression of high-grade lymphomas after the cure of H pylori infection had been described. The present prospective study was conducted to evaluate the effect of anti-H pylori therapy in stage I(E) high-grade gastric MALT lymphomas. PATIENTS AND METHODS: Sixteen patients with H pylori infection and stage I(E) gastric high-grade MALT lymphoma consented to a brief antibiotic therapy as first-line treatment from June 1995 through April 2000. Then, patients underwent intensive endoscopic follow-up examinations (+/- endoscopic ultrasonography) with biopsy to evaluate tumor response. Patients with significant improvement of gross lesions that accompanied regression of large cells were followed up without additional treatment. Patients without significant improvement were immediately referred to systemic chemotherapy. RESULTS: Eradication of H pylori was achieved in 15 patients and was accompanied by rapid gross tumor regression and disappearance of large cells in 10. All 10 of these patients with early response had subsequent complete histologic remission of lymphoma. The complete remission rate was 62.5% (95% confidence interval, 35.8% to 89.1%). The response rate was not affected by the tumor grading (proportion of large blast cells within the tumor) but was adversely affected by the depth of tumor invasion. At a median follow-up of 43.5 months (range, 21.1 to 67.4 months), all 10 of these patients remained lymphoma-free. The median duration of complete response was 31.2 months (range, 14.4 to 49.1 months). CONCLUSION: These results suggest that high-grade transformation is not necessarily associated with the loss of H pylori dependence in early-stage MALT lymphomas of the stomach.

Direct growth suppressive activity of interferon-alpha and -gamma on human gastric cancer cells.

BACKGROUND AND OBJECTIVES: Interferons (IFNs) exhibit anti-tumor activities through either immune modulation or direct anti-tumor effects. We have investigated the activity and mechanisms of IFN-alpha and IFN-gamma on the growth of TSGH9201, TMK-1 and AGS gastric cancer cells in vitro. METHODS: Activities of IFNs on cell growth were analyzed by measuring total cellular DNA. Effects of IFNs on apoptosis was evaluated by formation of in situ DNA breakage and DNA ladders. Effects of IFNs on cells cycle phase distribution were analyzed using flow cytometry. Levels of Bcl-2 family proteins after treatment with IFNs were analyzed using Western blot. RESULTS: Both IFN-alpha and IFN-gamma were active in suppressing the growth of TSGH9201 and TMK-1 cells, while AGS cells were resistant to treatment with IFNs. The IC(50)s of IFN-alpha for TSGH9201 and TMK-1 cells were 300 and 500 U/ml, respectively, and the IC(50)s of IFN-gamma were 40 and 2.0 U/ml, respectively. Both IFN-alpha- and IFN-gamma-induced cell cycle arrest in sensitive cells. IFN-gamma also increased cellular apoptosis, demonstrated by increasing in situ DNA damage and DNA fragmentation. IFN-gamma increased BAK protein levels and decreased Bcl-2 and Bcl-X(S) protein levels in TSGH9201 cells. CONCLUSIONS: IFN-alpha suppressed growth of gastric cancer cells through induction of cell cycle arrest. IFN-gamma suppressed cell growth through induction of both cell cycle arrest and apoptosis. IFN-gamma-mediated apoptosis was associated with the alteration in protein levels of Bcl-2, Bcl-X(S) and BAK.

Low-power laser therapy for gastrointestinal neoplasia.

The purpose of this study was to evaluate changes in the degree of neoplasia-induced stenosis and clinical symptoms before and after therapy with a contact low-power neodymium yttrium aluminum garnet (Nd:YAG) laser. Fifty patients with pathologically proven gastrointestinal (GI) neoplasia were studied; 21 with benign lesions and 29 with malignant tumors. The low-power contact Nd:YAG laser was applied toward the lesion, using an antegrade method as the scope was moved circumferentially and downward along the length of the lesions, step-by-step. The energy of the laser was 20W, with a duration of 1 to 2 min for each shot. Either the tumor was eradicated completely, or the neoplasia-induced stenosis was recanalized by laser via the endoscope. All benign lesions were completely remitted by laser therapy. The clinical symptoms in the 29 patients with malignant GI neoplasia showed a significant improvement (P < 0.001; Wilcoxon matched-pairs signed-rank test, one-tailed) after laser therapy in comparison with the symptoms before treatment. Malignant GI stenosis treated by laser resulted in recanalization in 93.1% of the 29 patients. Unfortunately, in 1 patient with gastric cancer, the disease progressively worsened after treatment. One of 3 patients with early cancer of the stomach who received laser therapy was found to have distant metastasis 2 years later. A patient with esophageal cancer developed an esophagobronchial fistula that was not a direct complication of the laser effect. Four patients with malignancies died of cancer progression during the 2 years of follow-up. We conclude that the low-power contact laser is a safe, convenient method for the treatment of both benign and malignant tumors. Patients with advanced obstructive lesions have a better quality of life after laser therapy.

Chronic idiopathic intestinal pseudo-obstruction.

Chronic idiopathic intestinal pseudo-obstruction (CIIP) is a rare heterogeneous clinical syndrome characterized by recurrent episodes of symptoms and signs of intestinal obstruction in the absence of a mechanically obstructing lesion. Dilatation of other viscera, such as the renal pelvis, ureter or urinary bladder, is identified in a minority of patients. We report the cases of two patients with CIIP presenting with abdominal fullness and constipation. Radiologic examination of the first patient revealed dilatation of the esophagus, stomach, duodenum and bowel loops up to the ascending colon. The nerve conduction velocity study of the right extremities revealed polyneuropathy and urinary bladder manometry revealed poor sensation. The patient had been admitted to our hospital three times for symptomatic relief within the prior six months. During the last admission, his symptoms persisted without response to medical treatment. Soon after discharge, the patient underwent surgery at another hospital and died of nutritional problems. The second patient was transferred to our hospital after an exploratory laparotomy was performed one month earlier. A radiographic examination revealed distention of the stomach, duodenum, small intestine and ascending colon, as well as bilateral hydronephrosis. Rheumatologic examination revealed no evidence of autoimmune disorder. The patient also had heavy proteinuria due to minimal change disease that was proven by renal biopsy. After receiving prokinetic, cathartic and corticosteroid medication for kidney disease, symptoms improved, but hydronephrosis persisted.

Cloning and characterization of a novel retinoid-inducible gene 1(RIG1) deriving from human gastric cancer cells.

Retinoids exert wide-spectrum anti-tumor activities, which are mediated via the induction of growth arrest, differentiation or apoptosis. To determine whether the effects of retinoids are mediated by specific gene activation or repression, SC-M1 CL23 gastric cancer cells, pretreated with either vehicle alone or all-trans retinoic acid (10 microM) for 1 day, were analyzed using the technique of differential display. A novel retinoid-inducible gene 1 (RIG1) was isolated. The full-length RIG1 cDNA contained 768 base pairs and encoded a protein of 164 amino acids with a molecular weight of 18 kDa. The RIG1 gene was ubiquitously expressed in normal tissue, and its expression was positively associated with cellular density. Nucleotide sequence analysis demonstrated that the RIG1 gene was similar to a recently-isolated TIG3 gene, and displayed 54% nucleotide sequence homology with a type II tumor suppressor gene H-REV-107-1. RIG1 cDNA, however, contained an extra 32 base pairs located at its 5' end and revealed three base pair differences for the remaining sequences leading to two amino acids substitution between the two encoded proteins. All-trans retinoic acid increased the level of RIG1 mRNA in a time- and concentration-dependent manner in SC-M1 CL23 gastric cancer cells. This was not observed for the H-REV-107-1 gene. The RIG1 regulation was related to cellular retinoid sensitivity. Both retinoic acid receptor alpha- and retinoic acid receptor gamma-selective agonists increased RIG1 mRNA level, and the retinoid x receptor-selective agonist potentiated this regulation. In conclusion, the cDNA of a novel retinoid-inducible gene RIG1 has been cloned. This gene is regulated by retinoic acid through the heterodimer of retinoic acid receptor and retinoid x receptor.

Expression of nuclear retinoid receptors in normal, premalignant and malignant gastric tissues determined by in situ hybridization.

Retinoids exhibit multiple functions through interaction with nuclear retinoid receptors and have growth-suppressive activity on gastric cancer cells. To better understand the roles of nuclear retinoid receptors during gastric carcinogenesis, we have used in situ hybridization to investigate expression of retinoic acid receptors (RARs) and retinoid x receptors (RXRs) in premalignant and malignant formalin-fixed paraffin-embedded gastric tissues. Histological sections of eight normal, 17 distal normal and nine gastric cancer tissues were hybridized with non-radioactive RNA probes for subtypes of RAR and RXR. Expression of RAR alpha, RAR beta, RAR gamma, RXR alpha and RXR beta was found in most cell types in gastric mucosa tissues from normal individuals as well as in distal normal tissues from cancer patients. Expression of RAR alpha and RAR beta were found in three and seven cancer tissues, respectively, and levels of RXR alpha mRNA were significantly decreased in poorly differentiated cancer tissues. Among the five investigated nuclear retinoid receptors, only expression of RAR alpha mRNA was significantly decreased in intestinal metaplasia, dysplasia and cancer tissues when compared to adjacent normal tissues. In conclusion, normal gastric mucosa expressed both RARs and RXRs, which supports the physiological role of retinoic acid on normal gastric mucosa. The decrease in RAR alpha expression in premalignant and malignant gastric tissues suggests a significant role of RAR alpha during gastric carcinogenesis.

The RARgamma selective agonist CD437 inhibits gastric cell growth through the mechanism of apoptosis.

Retinoids are differentiation-inducing agents that exhibit multiple functions. Their activities are mediated through interaction with nuclear retinoic acid receptors (RAR) and retinoid X receptors (RXR). We have investigated the activities of synthetic retinoids on the growth of five gastric cancer cell lines. The effects of agonists selective for RARalpha, RARbeta and RARgamma (AM580, CD2019 and CD437, respectively) on cell growth were determined, in comparison to all-trans retinoic acid, by measuring total cellular DNA. AM580 and CD2019 had little or no effect on the growth of all five cell lines. In contrast, the RARgamma agonist CD437 inhibited cell growth up to 90-99% in both retinoic acid sensitive and resistant gastric cancer cells at a concentration of 1 microM. The growth suppression caused by CD437 was accompanied by the induction of apoptosis as judged by morphological criteria and DNA ladder formation. However, the extent of CD437-induced growth suppression was not correlated with RARgamma mRNA levels, which indicates that CD437 induces apoptosis in gastric cancer cells via an RARgamma independent pathway.

Comparison of five PCR methods for detection of Helicobacter pylori DNA in gastric tissues.

Five different PCR methods for the detection of Helicobacter pylori were evaluated. The results of this study indicate that of the five PCR methods examined, the ureC (glmM) gene PCR is the most sensitive and specific for the detection of H. pylori in gastric biopsy specimens.

New one-week, low-dose triple therapy for the treatment of duodenal ulcer with Helicobacter pylori infection.

BACKGROUND: Antimicrobial therapy is the recommended treatment for duodenal ulcer associated with Helicobacter pylori infection. The eradication of bismuth-based triple therapy with bismuth subcitrate, metronidazole and amoxicillin is limited by low compliance, drug resistance and side-effects. Two-week proton pump inhibitor (PPI)-based triple therapy has a higher eradication rate but is costly. This study was designed to compare the efficacy, patient compliance and cost of short-term PPI-based triple therapy with those of bismuth-based triple therapy. METHODS: Ninety patients with active duodenal ulcer disease and H pylori infection, proven with the 13C-urea breath test and CLO test (Campylobacter-like organism test) were treated randomly in three therapeutic groups: Group A, DeNol 120 mg, amoxicillin 500 mg and metronidazole 250 mg four times a day orally for 14 days; Group B, omeprazole 20 mg plus clarithromycin 500 mg twice a day and amoxicillin 500 mg four times a day for 14 days; Group C, omeprazole 20 mg, clarithromycin 250 mg and metronidazole 500 mg twice a day for seven days. Nizatidine 150 mg twice a day was given continuously following the end of anti-H pylori therapy for each group. Two months later, endoscopy, the CLO test and 13C-urea breath test were repeated to assess the eradication rate of H pylori and the ulcer-healing rate. Drug tolerance was evaluated by patients themselves by daily recording of any side-effects. RESULTS: Eighty-four patients completed the entire course of therapy and evaluation for H pylori infection. The H pylori eradication rates in Groups A, B and C were 75% (21/28), 93% (26/28) and 89% (25/28), respectively (p = 0.466). The ulcer healing rate was 86% (24/28) in Group A and 89% (25/28) in Groups B and C (p = 0.764). A total of 74 patients (88%) were free from symptoms at the end of the triple therapy. Symptom relief was faster in patients with PPI-based triple therapy (Groups B and C) (days 3 and 4) than for patients with bismuth-based triple therapy (day 5). The cost of Group C therapy was lower than that for Groups A and B. There were no major side-effects in any of the patients. CONCLUSIONS: One-week triple therapy with omeprazole, clarithromycin and metronidazole is highly effected for the eradication of H pylori. A therapeutic regime of one week's duration with lower cost, good compliance and mild side-effects may offer a good choice for treatment of duodenal ulcer associated with H pylori infection in clinical practice.

High frequency of cytotoxin-associated gene A in Helicobacter pylori isolated from asymptomatic subjects and peptic ulcer patients in Taiwan.

Cytotoxin-associated gene A (CagA), expressed in about 60% of H. pylori isolates in Western countries, may play a role in the pathogenesis of peptic ulcer. In this study, we determined the prevalence and significance of the H. pylori cagA gene and protein expression in Taiwan. Genomic DNA from antrum biopsies and H. pylori isolates were analyzed for cagA using polymerase chain reaction, Southern hybridization, or colony hybridization. CagA seropositivity was analyzed using Helico blots. In addition, Western blotting was performed to detect the CagA protein. About 94% of antrum tissues from both asymptomatic subjects and duodenal ulcer patients and all 76 H. pylori isolates (21 asymptomatic subjects, 39 with duodenal ulcers, 13 with gastric ulcers, 2 with gastric cancers, and 1 with mucosa-associated lymphoid tissue [MALT] lymphoma) were positive for the cagA gene. Moreover 77 out of 78 H. pylori-positive serum and all 27 H. pylori lysates had anti-CagA antibodies or CagA protein, respectively. H. pylori isolated from patients with various upper gastrointestinal diseases in Taiwan contained the cagA gene and expressed CagA protein at high frequencies.

All-trans retinoic acid decreases susceptibility of a gastric cancer cell line to lymphokine-activated killer cytotoxicity.

All-trans retinoic acid (RA) was previously shown to regulate the growth of gastric cancer cells derived from the cell line SC-M1. This study was designed to investigate the effect of RA on the sensitivity of SC-M1 cells to lymphokine-activated killer (LAK) activity. RA at the concentration range of 0.001-10 microM was shown to induce SC-M1 cells to exhibit resistance to LAK activity in a dose-dependent manner. A kinetics study indicated that a significantly increased resistance was detected after 2 days of co-culturing SC-M1 cells with RA and reached a maximum after 6 days of culture. Similar results were obtained from two other cancer cell lines: promyelocytic leukaemia HL-60 and hepatic cancer Hep 3B. A binding assay demonstrated that the binding efficacy between target SC-M1 cells and effector LAK cells was not altered by RA. Flow cytometric analyses revealed that RA exhibited no effect on the expression of cell surface molecules, including HLA class I and class II antigens, intercellular adhesion molecule-1 and -2, and lymphocyte function antigen-3. Cell cycle analysis revealed that culture of SC-M1 cells with RA resulted in an increase in G0/G1 phase and a decrease in S phase, accompanied by a decrease in cyclin A and cyclin B1 mRNA as determined by Northern blot analysis. Additionally, RA was shown to enhance the expression of retinoic acid receptor alpha (RAR alpha) in SC-M1 cells, and to have no effect on the expression of RARbeta or RARgamma. Taken together, these results indicate that RA can significantly increase gastric cancer cells SC-M1 to resist LAK cytotoxicity by means of a cytostatic effect through a mechanism relating to cell cycle regulation. The prevailing ideas, such as a decrease in effector to target cell binding, a reduced MHC class I antigen expression or an altered RARbeta expression, are not involved.

Detection of alphafetoprotein-expressing cells in the blood of patients with hepatoma and hepatitis.

The presence of tumour cells in the blood circulation may predict disease recurrence and metastasis. We have evaluated the specificity and sensitivity of detecting hepatoma cells in blood using nested polymerase chain reaction with primers specific for the alphafetoprotein (AFP) gene. The nested polymerase chain reaction amplified a 270-base pair AFP DNA fragment from cDNA of Hep 3B hepatoma cells. In a reconstitution experiment, AFP mRNA was detected from peripheral mononuclear cells isolated from 10 ml of blood containing as few as ten Hep 3B cells. Peripheral mononuclear cells from the blood of 20 hepatoma patients were analysed, and 19 patients showed positive AFP mRNA expression. Seven of 13 samples from hepatitis patients also showed positive AFP mRNA expression. All five paired samples of peripheral blood or umbilical cord blood from pregnant mothers and their babies, respectively, showed positive AFP expression. None of 22 control samples was positive. The presence of AFP mRNA in the blood of hepatitis or hepatoma patients suggests the presence of circulating hepatoma cells or hepatocytes in the circulation. The high incidence of AFP mRNA in the blood of hepatoma patients supports the notion of early haematogenous spreading of the disease.