PTEN/MMAC1 mutations in hepatocellular carcinomas

Mutations in the PTEN/MMAC1 gene have been identified in several types of human cancers and cancer cell lines, including brain, endometrial, prostate, breast, thyroid, and melanoma. In this study, we screened a total of 96 hepatocellular carcinoma (HCC) samples from Taiwan, where HCC is the leading cancer in males and third leading cancer in females, for mutations in the PTEN/MMAC1 gene. Complete sequence analysis of these samples demonstrated a missense mutation in exon 5 (K144I) and exon 7 (V255A) from HCC samples B6-21 and B6-2, respectively. A putative splice site mutation was also detected in intron 3 from sample B6-2. Both B6-21 and B6-2 were previously shown to contain missense mutations in the coding sequences of the p53 gene. Functional studies with the two missense mutations demonstrated that while mutation V255A in exon 7 resulted in a loss of phosphatase activity, mutation K144I in exon 5 retained its phosphatase activity. Additionally, we identified a silent mutation (P96P) in exon 5 of the PTEN/MMAC1 gene from HCC sample B6-22. These data provide the first evidence that the PTEN/MMAC1 gene is mutated in a subset of HCC samples.

Serum hepatocyte growth factor before and after resection for hepatocellular carcinoma

BACKGROUND/AIMS

Hepatocyte growth factor (HGF) is the most potent hepatocyte proliferation stimulator. Serum HGF levels are high in various liver disease states such as cirrhosis, hepatocellular carcinoma (HCC) and hepatitis. But the role HGF plays in HCC is not clear at present. The purposes of this study are: 1) to reveal the HGF profile pre- and post-HCC resection, which has not been well-described before; and, 2) to analyze the relationships between the pre- and post-operative HGF levels and various clinical parameters.

METHODOLOGY

We performed a retrospective cohort study to check the HGF profiles before and after curative resections for HCC and to analyze the relationships between them by using clinical parameters from 35 consecutive patients at the Department of Surgery, National Taiwan University Hospital. Blood samples collected from another 23 healthy individuals admitted for health check-ups were used as normal controls. Serum HGF was determined with an ELISA kit.

RESULTS

The baseline HGF concentration in HCC patients was significantly higher than that in normal controls (1743+/-73 vs. 948+/-54 pg/ml, p<0.0001). The HGF concentrations on post-operative days (POD) 1, 3, 5, 7, and 14 were all significantly higher than those seen in normal controls (all p less than 0.0001). The first and third POD HGF values were significantly higher than the pre-operative level (p=0.00135 and 0.00187 respectively). The HGF concentrations would return to the pre-operative level on the fifth POD, but they never returned to normal level at the end of the two-week study. The pre-operative HGF level was affected by patient age (p=0.0236), and the post-operative peak HGF level was positively correlated with the pre-operative indocyanin green retention rate (ICGR15) and GOT level (p=0.0320 and 0.0234 respectively).

CONCLUSIONS

In this study, we proved, indirectly, that HGF was not secreted by the HCC tumor cells per se. The peak post-operative HGF level reflected the relative stress of the operation on the diseased liver, but did not reflect the absolute physical extent of liver resection. The relationships between HGF and the prognosis of the patients after HCC resection demands further investigation.

Loss of heterozygosity and microsatellite instability in hepatocellular carcinoma in Taiwan

Elucidation of the basic genetic changes of human hepatocellular carcinoma is important for the understanding and treatment of this cancer. We used microsatellite polymorphism markers to study 30 cases of hepatocellular carcinoma (34 tumours) on all human chromosomes. DNA from 34 pairs of hepatocellular carcinomas and corresponding non-tumour parts was prepared. Loss of heterozygosity (LOH) and microsatellite instability on 23 chromosomes were investigated by 231 sets of microsatellite markers. More than 20% LOH was shown for loci on 16q (47.1%), 13q (32.4%), 17p (32.4%), 5q (26.5%), 11p (23.5%) and 9p (20.6%). The commonly affected regions were mapped to 16q12.1, 16q12.2, 16q24, 13q12.1-32, 17p13, 5q32, 5q34, 5q3, 11p15, 11q23-24 and 9p21. Hepatitis B virus carriers had a significantly higher frequency of LOH on chromosomes 5q, 11p and 16q. Furthermore, larger tumour size tended to have higher frequency of LOH at D16S409 locus (16q12.1). Microsatellte instability was only found in 12 of 231 markers and the frequency is very low. These data suggest that the chromosomes 16q, 13q, 17p, 5q, 11p and 9p might participate in hepatocarcinogenesis. However, microsatellite instability might play little role in the development of this cancer in Taiwan.

Enterolith: an unusual cause of afferent loop obstruction

Most cases of enterolith have been reported in association with the diverticula of small bowel. We report here a case of a patient in whom a huge enterolith developed in the afferent loop of Billroth II anastomosis with ensuing obturation obstruction. The enterolith was clearly shown on the preoperative abdominal computed tomograph and was removed through a duodenotomy. The postulated mechanism of the enterolith formation is impaired duodenal evacuatory motor activity due to previous gastrectomy.

Chromosomal abnormality in hepatocellular carcinoma by comparative genomic hybridisation in Taiwan

The elucidation of the genetic changes of hepatocellular carcinoma (HCC) is very important for understanding the molecular mechanism of liver carcinogenesis. In order to identify the gains or losses in DNA sequence copy number in HCC, we used comparative genomic hybridisation to study 40 cases (44 tumours) of HCC. Tumour DNA and DNA from non-neoplastic liver tissue were labelled with different fluorochromes and then simultaneously hybridised to normal metaphase spread chromosomes. An image acquisition system was used to quantitate signal intensities contributed by tumour and reference DNA along the entire length of each chromosome. Regions of amplification and deletion were demonstrated as quantitative alterations. Losses were prevalent on chromosome regions 16q (43%), 17p (20%), 13q (20%), 4q (15%) and 8p (15%). Gains frequently occurred on 8q (30%), 1q (20%), 6p (20%) and 17q (18%). Hepatitis B virus carriers had a significantly higher frequency of losses on chromosome 16q. Furthermore, the minimal region of losses was narrowed down to 16q11-q22. This study confirms the presence of previously known chromosomal aberrations in HCC and highlights a new significant correlation between losses on chromosome 16q and hepatitis B virus carriers.

Secretion of acute-phase proteins before and after hepatocellular carcinoma resection

Hepatocyte growth factor (HGF), interleukin-6 (IL-6), and C-reactive protein (CRP) are acute-phase reactants that are usually present at high concentrations in the serum of patients with liver disease. However, the origin of these high serum concentrations is not completely understood, and whether hepatocellular carcinoma (HCC) tissue is a contributing factor is a controversial issue. The purpose of this study was to investigate the profiles of these three proteins in patients with HCC before and after tumor resection, and to study factors that might affect the serum concentrations of these proteins. A retrospective cohort study was performed in 34 consecutive patients who underwent HCC resection at the National Taiwan University Hospital. Blood samples were collected before surgery and on days 1, 3, 5, 7, and 14 postoperatively for serum concentration determinations of these three proteins. Twenty-three patients admitted for health examinations were enrolled as normal controls. Multiple regression analysis was conducted to evaluate the correlations between the pre- and postoperative cytokine concentrations and various clinical parameters. Compared with normal controls, the HCC patients had a significantly higher preoperative concentration of HGF (1,472 +/- 73 vs 948 +/- 54 ng/mL, p < 0.001) and IL-6 (44.1 +/- 6.9 vs 8.1 +/- 3.2 pg/mL, p = 0.012). These concentrations peaked on the first postoperative day and then declined to preoperative values on the fifth postoperative day. The CRP concentration was also higher in HCC patients (0.88 +/- 0.22 vs 0.21 +/- 0.06 mg/dL, p = 0.222), but the difference was not statistically significant. However, the CRP concentration did not return to the preoperative value within 2 weeks postoperatively. Preoperatively, HGF and CRP concentrations were positively affected by larger tumor size, and IL-6 concentration was negatively affected by hepatitis B surface antigen positivity and a higher indocyanine green (ICG) retention rate. In summary, the serum concentrations of HGF and IL-6 were significantly higher in HCC patients than in normal controls. The serum concentrations of HGF, IL-6, and CRP rose dramatically after HCC resection. The concentrations of these proteins were affected by different clinical parameters. We proved indirectly that high serum concentrations of HGF, IL-6, and CRP in patients with HCC do not result primarily from synthesis by the tumor cells. Whether the preoperative concentrations of these proteins correlate with the clinical outcome needs further follow-up.

Serial brain SPECT images in a case of Sydenham chorea

BACKGROUND

The pathophysiological nature of Sydenham chorea (SC) has been presumed to be an autoimmune-mediated inflammatory process. Positron emission tomography in SC has revealed a striatal hypermetabolism that might explain the transient neuronal dysfunction. However, any focal hyperperfusion in the striatum or its related structures has not been demonstrated in previous single photon emission computed tomographic (SPECT) imaging studies, which raised a concern about the pathogenesis of the striatal hypermetabolism.

OBJECTIVE

To investigate the cerebral perfusion patterns of the subcortical structures by using serial technetium Tc 99m-ethyl cysteinate dimer SPECT in a case of SC, which may provide a clue for the pathophysiological mechanisms.

DESIGN

A case report and serial SPECT studies.

CASE PRESENTATION

A girl aged 4 years 3 months showed severe generalized choreic movements with concomitant signs of acute pharyngitis. Results of a laboratory study taken 7 days after the onset of chorea showed elevated antistreptolysin O titer, C-reactive protein levels, and erythrocyte sedimentation rate. Other laboratory data, throat culture, echocardiography, brain magnetic resonance imaging, and electroencephalography did not reveal any abnormalities. Five days after treatment with haloperidol and penicillin, the chorea began to improve slowly, and completely resolved in 2 months.

RESULTS

Three serial SPECT images and semiquantitative analysis of cerebral perfusion were obtained. Cerebral perfusion in the striatum and thalamus was markedly increased bilaterally during the stage of active chorea and then returned nearly to its baseline level during the convalescent phase. These cerebral perfusion patterns were concordant with semiquantitative analysis.

CONCLUSIONS

Hyperperfusion in both the striatum and thalamus in our patient may reflect the subcortical inflammatory processes in SC. The unequivocal SPECT findings in our patient are difficult to reconcile with the negative findings of previous SPECT studies but may suggest the heterogeneity of the perfusion patterns in SC.

Overexpression of p53 is not associated with drug resistance of gastric cancers to 5-fluorouracil-based systemic chemotherapy

BACKGROUND/AIMS

Recent in vitro evidence has strongly suggested that most anti-cancer drugs exert their cytotoxic effects via a p53-dependent apoptosis pathway. An intact p53 molecule appears to be a prerequisite for the cancer cells to be susceptible to these drugs. In this study, we specifically examined if overexpression of p53 may confer drug resistance on human gastric cancer.

METHODOLOGY

All patients were treated by an empirical HDFL regimen (weekly 24-hour infusion of 5-FU, 2,600 mg/m2 and leucovorin, 300 mg/m2) in a prospective phase II clinical trial. Among them, patients with adequate pre-chemotherapy gastric cancer tissues for immunohistochemical studies were selected for this study. A p53 DO7 monoclonal antibody was used to detect the overexpression of p53. The results were designated as "-" or "+" by the independent interpretation of two pathologists.

RESULTS

A total of 30 patients, 18 men and 12 women, with a median age of 61.5 years (range: 32-78 years), were studied. There were 15 responders and 15 non-responders to HDFL chemotherapy. The percentage of p53 overexpression with positive DO7 staining was 20.0% (6 out of 30). There were no significant differences in the pertinent clinicopathologic features between the patients with positive staining of p53 and the patients with negative staining of p53. Three out of 6 (50.0%) patients with positive staining of p53 and 12 out of 24 (50.0%) patients with negative staining of p53 responded to chemotherapy, respectively (p = 1.000 by Fisher's exact test).

CONCLUSIONS

Our data suggested that the overexpression of p53 does not predict drug resistance to 5-FU of human gastric cancer.

Intrahepatic bilomas associated with hepatic arteriovenous malformation

A 26 year-old female presented with progressive intermittent right upper quadrant pain. Hepatic arteriovenous malformation with small intrahepatic bilomas were found. She underwent hepatic artery ligation for control of her abdominal pain. Though the abdominal pain subsided after the hepatic artery ligation, the intrahepatic bilomas progressed. It is possible that the hepatic arteriovenous malformation (AVM) might reduce blood flow to the bile duct and then induce ischemia in the peribiliary capillary plexus, thus leading to bile duct necrosis and formation of bilomas, which could be further aggravated by hepatic artery ligation.

Water-soluble contrast study predicts the need for early surgery in adhesive small bowel obstruction

BACKGROUND

The optimal period of conservative treatment for adhesive small bowel obstruction remains controversial. This study sought to determine whether a 24-h abdominal radiograph after oral Urografin is a reliable indicator for operation in patients with adhesive small bowel obstruction.

METHODS

One hundred and sixty-one patients who suffered from adhesive intestinal obstruction without clinical evidence of strangulation or gangrene underwent a Urografin study. Some 40 ml Urografin mixed with 40 ml distilled water was administered either orally or via a nasogastric tube to each patient. Serial plain abdominal radiographs were taken 4, 8, 16 and 24 h later. If an earlier plain radiograph showed that contrast medium had reached the ascending colon, subsequent radiographs were not taken.

RESULTS

Contrast medium reached the colon within 24 h in 112 patients (70 per cent). These patients were all treated successfully with non-operative methods. Contrast medium was not observed in the colon within the first 24 h in 49 patients (30 per cent). Operation was performed in 47 of these patients and non-operative treatment was given in two. The sensitivity, specificity, accuracy, positive predictive value and negative predictive value of Urografin reaching the colon within 24 h as an indicator for non-operative treatment were 98, 100, 99, 100 and 96 per cent respectively.

CONCLUSION

All patients with evidence of Urografin reaching the colon within 24 h were treated successfully with non-operative methods. The results of this prospective study suggest that patients with adhesive intestinal obstruction in whom contrast medium fails to reach the colon within 24 h should receive prompt surgical intervention.

Gastric leiomyosarcoma mimicking a cystic tumor at the pancreatic tail--one case report

A 73 year-old female patient suffered from anemia and a palpable abdominal mass. Abdominal ultrasonography and magnetic resonance imaging revealed a lesion with papillary excrescences at the pancreatic tail. Endoscopic retrograde cholangiopancreatography showed a normal pancreatic duct, but a small submucosal tumor was found in the stomach incidentally. Laparotomy disclosed an exophytic tumor arising from the submucosal layer of the stomach. Pathology revealed a gastric leiomyosarcoma with remarkable liquefaction and cystic change. Gastric leiomyosarcoma can be so necrotic as to be mistaken for a cystic tumor. It is critically important to differentiate the peripancreatic cystic lesion because the treatment strategy is totally different.

Infrequent mutations and no methylation of CDKN2A (P16/MTS1) and CDKN2B (p15/MTS2) in hepatocellular carcinoma in Taiwan

CDKN2A (p16INK4A/MTS1) and CDKN2B (p15INK4B/MTS2) have recently been shown to be potent inhibitors of the cyclin D/cyclin-dependent kinase-4 complex. Both genes are candidates for the putative tumour suppressor genes located at chromosome 9p21 and are frequently inactivated in many human cancers through homozygous deletion. More recently, another reported pathway of inactivation involves loss of transcription associated with de novo methylation of the 5' CpG island of p16/MTS1 and p15/MTS2 in human cancers. We examined a total of 34 tumours from 30 hepatocellular carcinoma (HCC) patients for deletion, mutation and DNA methylation of these two genes by polymerase chain reaction (PCR) amplification, sequence analysis and Southern blot. Homozygous deletions of P16/MTS1 exon 1 were only identified in 1 of 30 cases (3%). Homozygous deletions of p15 exon 1 or exon 2 were found in 7 of 30 cases (13%). Automated sequencing analysis of p16 exon 1 and 2 and p15 exon 1 and 2 failed to demonstrate mutations in either p16 or p15 in any of these specimens. No aberrant 5' CpG island hypermethylation of p16 or p15 was found in any of the primary tumours by Southern blot. These data suggest that the p16/MTS1 gene has a limited role in HCC. However, deletions of the p15/MTS2 gene are found in 13% HCC and might be involved in a subset of HCC.

Hepatocellular carcinoma in children: clinical review and comparison with adult cases

BACKGROUND

Hepatocellular carcinoma (HCC) in children was rarely reported and usually included with hepatoblastoma in most studies of pediatric liver malignancies despite different clinical behaviors. The authors report their experience in pediatric HCC and discuss its differences from adult HCC.

METHODS

A retrospective review of radiographic, laboratory, pathological, and therapeutic data in 55 children with HCC was performed. The liver function was graded by modified Child's classification. Kaplan-Meier survival curves in various therapeutic and Child's groups were plotted, and log-rank test was used to detect differences among survival curves.

RESULTS

Although children with HCC mostly presented with advanced disease at diagnosis, disturbances of liver function were unremarkable. Sixty-eight percent of cases concurred with liver cirrhosis. The median survivals for resectable, chemotherapeutic, and untreated HCCs were 23, 3, and 2 months, respectively. Resectable HCC significantly posed a much better prognosis. However, the resectability was unsatisfactory (18.2%). Resection was limited because of anatomic unfeasibility including bilateral involvement (62.5%), portal vein thrombi (41.7%), distant metastasis (29.1%), para-aortic lymphadenopathy (18.8%), inferior vena cava thrombi (16.7%), and hilar invasion (6.3%). Distant metastasis was the most ominous for survival in children with unresectable HCC.

CONCLUSIONS

HCC behaved somewhat differently between children and adults. Surgical resection represented the best hope of long-term survival. The outcome in children could not keep up with that in adults because of a diagnostic delay. Hence, alpha-fetoprotein and sonography screening in carrier children should be worthwhile.

Relatively low expression of multidrug resistance-1 (MDR-1) and its possible clinical implication in gastric cancers

The mechanism of drug resistance of gastric cancer cells has rarely been investigated. We specifically examine the magnitude and the biologic significance of multidrug resistance-1 (MDR-1) expression in human gastric cancer. All patients had previously been treated in prospective clinical trials for advanced gastric cancer in our institution. Patients with adequate prechemotherapy gastric cancer tissues for immunohistochemical studies by a C219 monoclonal antibody were selected for the determination of the expression rate of MDR-1. The results were designated as negative or positive by the independent interpretation of two pathologists. A subgroup of patients who had been treated with doxorubicin- or etoposide-containing regimens were selected for further correlation with drug sensitivity. Between 1990 and 1996, a total of 60 patients, 38 men and 22 women with a median age of 55 years, were studied. Eight (13.3%; 95% confidence interval, 6%-25%) of them had MDR-1 expression. None of the pertinent clinicopathologic features, including the histopathologic types of the tumors and the extent of the diseases, correlated with the expression of MDR-1. Among the 30 patients who had received doxorubicin- or etoposide-containing combination chemotherapy, 3 (10%; 95% confidence interval, 3%-27%) were designated positive for MDR-1 expression. None of the 3 patients responded to chemotherapy, whereas 19 (70.4%) of the 27 patients who had not expressed MDR-1 did respond (p=0.041 by Fisher's exact test). We conclude that the expression of MDR-1 in gastric cancer is relatively low. Its expression, however, is clinically relevant and is useful in predicting the chemoresistance of patients with gastric cancer receiving doxorubicin- or etoposide-containing combination chemotherapy.

High expression of thymidylate synthase is associated with the drug resistance of gastric carcinoma to high dose 5-fluorouracil-based systemic chemotherapy

BACKGROUND

In the past 4 years, the weekly 24-hour infusion of high dose 5-fluorouracil (5-FU) and leucovorin in the treatment of patients with advanced gastric carcinoma has been prospectively studied at the authors' institution. This has enabled them to explore the possibility that the level of expression of thymidylate synthase (TS), the target enzyme of 5-FU, is related to the drug sensitivity of gastric carcinoma to 5-FU-based chemotherapy.

METHODS

To be eligible for this study, patients were required to have received high dose 5-FU and leucovorin chemotherapy (weekly 24-hour infusions of 5-FU, 2,600 mg/m2, and leucovorin, 300 mg/m2) and to have had adequate prechemotherapy gastric carcinoma tissues for immunohistochemical study. TS106 monoclonal antibody was used to detect the expression of TS. A visual scoring system, which ranged from 0 to 3+, was adopted by 2 independent pathologists to semiquantitate the intensity of TS expression.

RESULTS

Between 1993 and 1996, a total of 30 patients, 18 men and 12 women, with a median age of 61.5 years, were enrolled. Of these patients, 16 (53.3%) and 14 (46.7%) had high and low expression of TS, respectively. Two of the 16 patients (12.5%) with high expression of TS and 13 of the 14 patients (92.9%) with low expression of TS responded to chemotherapy (P < 0.001, chi-square test). The median overall survival was 10 months for patients with low TS expression and 4 months for patients with high TS expression (P < 0.01, log rank test).

CONCLUSIONS

The data from this study suggest that the expression of TS, as determined by immunohistochemistry, is a relatively reliable indicator of whether 5-FU should be used in the treatment of patients with gastric carcinoma.

Comparative efficacy of terfenadine, loratadine, and astemizole in perennial allergic rhinitis

Nonsedating H1 antihistamines such as terfenadine, loratadine, and astemizole are widely prescribed for the treatment of allergic rhinitis. The comparative efficacy of these agents has not been thoroughly studied. We studied 14 subjects in an open-label four-way crossover trial. Patients were recruited from an outpatient allergy clinic. Inclusion criteria were documented rhinitis symptoms for at least 2 years before the study and skin-test positivity in response to perennial allergens. Each subject underwent sequential 2-week trials of each of four H1 antihistamines: terfenadine, loratadine, astemizole, and chlorpheniramine. No placebo was included. Outcome measures were subjective rhinitis symptom scores, overall efficacy scores, and concomitant pseudoephedrine use. In addition, nasal-examination scores were obtained by way of physician assessment at the end of each 2-week trial, and side effects were tabulated. Nasal-examination scores for each of the four H1 antihistamines were significantly better than the baseline scores (p < 0.05). No statistically significant differences in rhinitis symptom scores, overall efficacy scores, or concomitant pseudoephedrine use were noted. We detected no clinically significant differences in efficacy among terfenadine, loratadine, astemizole, and chlorpheniramine in the treatment of perennial allergic rhinitis.