Shih Huang Chan

Expression of vascular endothelial growth factor in normal liver and hepatocellular carcinoma: An immunohistochemical study

Angiogenesis is of vital importance during the development and progression of solid tumors. To examine the role of vascular endothelial growth factor (VEGF) in hepatocarcinogenesis, we evaluated the expression of peptide in normal human liver (n = 6) and in 36 cases of hepatocellular carcinoma (HCC). Immunoreactivity for VEGF was present in the extracellular matrix of the portal tracts in the normal and nontumor part of liver, but not in hepatocytes and bile duct epithelium. For HCC, variable amounts of VEGF were expressed in 13 cases (36.1%) of tumor cells. Using a logistic regression model, expression of VEGF was significantly associated with a higher proliferative index (P = .01) and sonographic portal vein thrombosis (P = .05). However, VEGF expression did not correlate with a biochemical liver profile, alpha-fetoprotein levels, histological grading, gender, or clinical stage of cirrhosis (P > 0.1, respectively). Log-rank test showed that evaluation of VEGF did not provide more prognostic information (P > .5) than that from tumor volume and portal vein thrombosis (P < .01, respectively). In addition, VEGF was always present in the fibrovascular stroma or pericellular matrix of HCC, although no strong relationship was observed with the expression of VEGF in tumor cells (P > .5). Our data suggested that expression of VEGF may characterize a progression toward higher proliferation in hepatocarcinogenesis in vivo. The relevance of VEGF existing in the extracellular matrix of the normal liver and HCC remains to be clarified.

Overexpression of c-met as a Prognostic Indicator for Transitional Cell Carcinoma of the Urinary Bladder: A Comparison With p53 Nuclear Accumulation

PURPOSE The c-met proto-oncogene encodes a receptor tyrosine kinase (Met) and has been shown to play a role in oncogenesis. Given that high titers of hepatocyte growth factor, the specific ligand for Met, are excreted in the urine and tend to reflect disease activity of bladder cancer, we performed this study to examine the clinical significance of Met in human bladder cancer. MATERIALS AND METHODS We studied the mRNA expression and genomic alteration of c-met in five bladder cancer cell lines. Significance of Met overexpression was then compared with p53 nuclear accumulation (TP53) in primary bladder cancer (n = 142 patients). RESULTS Expression of c-met mRNA tended to positively correlate with differentiation of cancer cell lines in the absence of point mutation. High expression of Met was found in seven cases (4.9%), low expression in 32 cases (22.5%), and negative expression in 103 cases (72.5%). Expression of Met was positively associated with histologic grade, stage classification, tumor size, and nodular tumor growth (P <.05, respectively); however, it was not related to TP53 status. Factors that predicted disease progression were tumor stage, Met status, and TP53 accumulation (P <.05, respectively). Indicators for poor long-term survival were invasive cancer, multiple tumors, and Met overexpression (P =.0006,.01, and.04, respectively). CONCLUSION The c-met proto-oncogene plays a more important role in the progression of bladder carcinogenesis than p53. Evaluation of Met expression could identify a subset of bladder cancer patients who may require a more intensive treatment strategy.

Bleeding peptic ulcer--risk factors for rebleeding and sequential changes in endoscopic findings.

From September 1991 to December 1992, a prospective study was conducted to determine the risk factors and residual risk of rebleeding, and the evolutionary endoscopic changes in peptic ulcers that rebled. Emergency endoscopies were performed on 452 patients with haematemesis or a melaena, or both within 24 hours of admission. If the lesions were actively bleeding, then the patients were treated with injection sclerotherapy. A multivariate analysis of clinical, laboratory, and endoscopic variables of 204 patients with ulcer bleeding showed that hypovolaemic shock, a non-bleeding visible vessel, and an adherent clot on the ulcer base were independently significant in predicting rebleeding (p < 0.05). Considering these three factors according to the estimates of their regression coefficients showed that a non-bleeding visible vessel was the strongest predictor of rebleeding. The study of the residual risk of rebleeding after admission showed that most rebleeding episodes (94.1%), including all associated with hypovolaemic shock, surgical treatment, and death, occurred within 96 hours of admission. After this time, the residual risk of rebleeding was less than 1%. Study of the changes in endoscopic findings before and after rebleeding illustrated that all ulcers with a visible vessel or adherent clot showed at follow up endoscopy were derived from ulcers with initial major stigmata. It is concluded that hypovolaemic shock, a non-bleeding visible vessel, and an adherent clot on an ulcer base are of independent significance in predicting rebleeding. Observation for 96 hours is sufficient to detect most rebleeding episodes after an initial bleed from peptic ulcer.

Expression patterns of erbB receptor family in normal urothelium and transitional cell carcinoma. An immunohistochemical study.

Abstract The class I tyrosine kinase growth-factor receptors include epidermal growth factor receptor (EGFR), ErbB2 (c-erbB-2, HER-2/neu), ErbB3 and ErbB4. To elucidate their role in the regulation of homeostasis and carcinogenesis, we examined the expression of the receptors in normal urothelium and in urothelial carcinoma by immunohistochemistry. EGFR was expressed in the basal cells of normal urothelium, while ErbB2, ErbB3 and ErbB4 were present mainly in the superficial layer. A distinct reciprocal distribution was observed between the EGFR and the remaining members of the subclass (P = 0.0001). Both BCL-2 protein and Ki-67 antigen (MIB-1) showed a strong positive association with EGFR (P = 0.002) and an inverse correlation with ErbB2, ErbB3 or ErbB4 (P = 0.0004, 0.0000, and 0.001, respectively). With regard to carcinoma, there was no important relationship between receptor overexpression and tumour grading (P > 0.1), while only EGFR overexpression was correlated with muscular invasion (P = 0.02). Coexpression of EGFR-ErbB3 and ErbB3-ErbB4 was more often detected in high-grade tumours and correlated with the extent of tumour invasion. Our data indicate that class I receptors are differentially expressed in normal urothelium in vivo, but an orchestrated expression pattern does not exist during tumorigenesis.

Genetic susceptibility to nasopharyngeal carcinoma within the HLA-A locus in Taiwanese

NPC is an epithelial tumor that is highly prevalent among the southern Chinese. Numerous studies have indicated that specific HLA haplotypes and genes within the HLA complex are associated with NPC. As a first effort to localize the gene responsible for susceptibility, the HLA‐A, ‐B, and ‐A2 subtypes were examined for their association to NPC. Consistent with previous reports, frequencies of HLA‐A2 [OR = 2.50, pc = 0.020 (study population); OR = 3.73, pc = 0.0030 (≥40 years old)] were significantly higher in patients with NPC than in healthy controls. Two‐locus analysis indicated that A2+B46+ individuals are at greater risk for NPC than A2−B46− individuals in both the population studied and the ≥40‐year‐old group. This, however, may be due to the close linkage of these 2 genes. Moreover, A2+B38+ individuals were at higher risk than A2−B38− individuals in both the population studied and the ≥40‐year‐old group; A2 and B38 are not genetically linked. These findings suggest that B38 or B46 alone cannot confer a high risk of NPC but that, in conjunction with A2, B38 or B46 positivity greatly increases risk. None of 5 A2 subtypes identified from studied populations was significantly associated with NPC. Microsatellite marker D6S211, located 97 kb telomeric to HLA‐A, was analyzed for its association with NPC. Allele 4 of D6S211 was significantly associated with NPC (OR = 3.97, pc = 0.0042). These results strongly support the hypothesis that genes associated with susceptibility to NPC in the HLA region are within the HLA‐A locus.

Nasopharyngeal carcinoma-susceptibility locus is localized to a 132 kb segment containing HLA-A using high-resolution microsatellite mapping.

Nasopharyngeal carcinoma (NPC) is an epithelial tumor uniquely prevalent in southern Chinese. HLA‐A2 is associated with NPC. In a previous study, we showed that the genes associated with susceptibility to NPC are primarily located within the HLA‐A locus in Taiwanese NPC patients. However, the pathogenic genes causing NPC susceptibility remain unknown. Here, 8 polymorphic microsatellite markers distributed over a 1 megabase region surrounding the HLA‐A locus were subjected to genetic analysis for the NPC‐susceptibility locus. Statistical studies of associated alleles detected on each microsatellite locus showed that the NPC‐ susceptibility genes are most likely located between the D6S510 and D6S211 markers within a 132 kb segment containing the HLA‐A locus. These results undoubtedly would facilitate the further positional cloning of the NPC‐susceptibility locus, which has been elusive for the past 30 years.

Clinical Presentation and Prognostic Factors in Sodium Monofluoroacetate Intoxication

BACKGROUND The diagnosis of sodium monofluoroacetate intoxication in humans is usually based on a history of ingestion and clinical findings. Although several previous reports have described the clinical course and outcome of patients who ingested this drug, prognostic indicators of short-term survival are not available. METHODS A retrospective study of 38 consecutive cases of sodium monofluoroacetate poisoning at the National Cheng Kung. University Hospital, 1988-1993, to analyze the clinical findings and to predict mortality. RESULTS Seven of 38 patients (18%) died. The most common symptom was nausea or vomiting (74%). The most frequent ECG finding was nonspecific ST-T and T wave abnormalities (72%). Hypocalcemia (42%) and hypokalemia (65%) were the common electrolyte abnormalities. The clinical and laboratory characteristics were compared for the survival and mortality groups. Significant differences in hypotension, respiratory rate, pulse rate, creatinine, potassium, elevated alanine aminotransferase, pH, PCO2, APACHE II score, and subjective respiratory distress were noted. Discriminant analysis identified hypotension, increased serum creatinine, and decreased pH as the most important predictors of mortality, with sensitivity of 86% and specificity of 96%. CONCLUSIONS Hypotension and the early onset of metabolic acidosis and increased serum creatinine are associated with poor short-term survival. These prognostic variables can be useful in the care of patients with suspected sodium monofluoroacetate intoxication. It is suggested that all such patients should be observed intensively for at least 48 h.

A clustered ground‐glass hepatocyte pattern represents a new prognostic marker for the recurrence of hepatocellular carcinoma after surgery

The recurrence of hepatocellular carcinoma (HCC) after hepatectomy is a serious event. It has been demonstrated that different ground‐glass hepatocyte (GGH) patterns harbor specific hepatitis B virus (HBV) pre‐S deletion mutants and represent preneoplastic lesions in chronic HBV infection. In the current study, the authors investigated whether a specific GGH pattern in nontumorous liver tissues was associated with the recurrence of HBV‐related HCC after surgery.

Evaluation of Etest for Direct Antifungal Susceptibility Testing of Yeasts in Positive Blood Cultures

ABSTRACT The performance of the Etest (AB BIODISK, Solna, Sweden) for direct antifungal susceptibility testing of yeasts in positive blood cultures was compared with that of the macrodilution method for determining the MICs of five antifungal agents. Culture broths with blood from bottles positive for yeasts were inoculated directly onto plates for susceptibility testing with the Etest, and the MICs were read after 24 and 48 h of incubation. A total of 141 positive blood cultures (72 cultures of Candida albicans, 31 of Candida tropicalis, 14 of Candida glabrata, 11 ofCandida parapsilosis, 3 of Candida krusei, and 3 of Cryptococcus neoformans, 4 miscellaneous yeast species, and 3 mixed cultures) were tested, and the rates of MIC agreement (±1 log2 dilution) between the direct Etest (at 24 and 48 h, respectively) and macrodilution methods were as follows: amphotericin B, 81.8 and 93.5%; flucytosine, 84.8 and 87.7%; fluconazole, 89.4 and 85.5%; itraconazole, 69.7 and 63.8%; ketoconazole, 87.9 and 79.0%. By a large-sample t test, the difference in log2 dilution between the direct Etest and the macrodilution method was found to be small (P< 0.05). The lone exceptions were ketoconazole at 48 h of incubation and itraconazole at both 24 and 48 h of incubation (P > 0.05). By Tukeys multiple comparisons, the difference between the direct Etest (48 h) and reference methods among different species was found to be less than 1 log2dilution. When the MICs were translated into interpretive susceptibility, the minor errors caused by the direct Etest (at 24 and 48 h, respectively) were as follows: flucytosine, 2.3 and 1.4%; fluconazole, 3.0 and 3.6%; itraconazole, 21.2 and 21.3%. Itraconazole also produced an additional 3.0 and 3.6% major errors as determined by the direct Etest at 24 and 48 h, respectively. It was concluded that, except for itraconazole, the Etest method was feasible for direct susceptibility testing of blood cultures positive for yeasts. The method is simple, and the results could be read between 24 and 48 h after direct inoculation, whenever the inhibition zones were discernible.

Lin28B Is an Oncofetal Circulating Cancer Stem Cell-Like Marker Associated with Recurrence of Hepatocellular Carcinoma

By using an expressed sequence tag bioinformatic algorithm, we identified that Lin28 homolog B (Lin28B) may have an oncofetal expression pattern which may facilitate detecting cancer cells in adults. It is also reported to be a potential marker for cancer stem cells. Therefore, we sought to verify oncofetal-stemness characters of Lin28B and test its potential as a circulating cancer stem cell-like marker in adult HCC patients. Lin28B mRNA was examined in a panel of fetal tissue, adult tissue and tumors. Lin28B was over-expressed or knocked down in HepG2 cells to evaluate its potential as a stem cell-like marker. RT-qPCR for Lin28B was performed in the peripheral blood mononuclear cells from patients with HCC receiving surgery (n=96) and non-HCC controls (n=60) and analyzed its clinical significance. Lin28B showed an oncofetal expression pattern. Its overexpression could upregulate stemness markers (OCT4, Nanog and SOX2) and enhance tumorsphere formation in vitro. Lin28B knockdown had opposite effects. Circulating Lin28B was detected in peripheral blood mononuclear cells in 3 cases (5%) of non-HCC controls and 32 cases (33.3%) of HCC patients. In HCC patients, circulating Lin28B was associated with high tumor grade (P=0.046), large size (P=0.005), high AJCC stage (P=0.044) and BCLC stage (P=0.017). Circulating Lin28B was significantly associated with decreased recurrence-free survival (P<0.001). Circulating Lin28B separated early stage HCC into 2 recurrence-free survival curves (P=0.003). In multivariate analysis, circulating Lin28B was an independent variable associated with early recurrence (P=0.045) and recurrence in early stage HCC (P=0.006). In conclusion, the oncofetal gene Lin28B is a potential oncofetal cancer-stem-cell-like circulating tumor cell marker that correlates with HCC recurrence after hepatectomy. Circulating Lin28B could refine early AJCC stages. Our finding supports the possible use of a TNMC (C for circulating tumor cells) staging system in HCC.