Po-Huang Lee

ELASTIC MODULUS MEASUREMENTS OF HUMAN LIVER AND CORRELATION WITH PATHOLOGY

Viral hepatitis causes fibrosis in the liver and may change mechanical properties of the liver. To evaluate the impact of fibrosis on elastic properties of human liver and to investigate potential benefits of ultrasonic elasticity imaging, 19 fresh human liver samples and 1 hepatic tumor (focal nodular hyperplasia) sample obtained during operations were studied. Simple 1-D estimates based on the cyclic compression-relaxation method were performed. Elastic modulus values were derived from the predetermined strain (controlled by a step motor system) and the stress values (measured by an electronic balance). Each specimen subsequently received histologic examination and a grade of liver fibrosis was scored from 0 to 5. Results show that the elastic modulus values were on the order of several hundreds to thousands of Pascals. The elastic modulus generally increased with the fibrosis grade, although some discrepancies existed at the middle grades of fibrosis (scores 1 to 3). The correlation between the fibrosis score and the elastic modulus was significant (p < 0.01) based on the statistical analysis using the Pearson correlation method. In addition, the relation between the elastic modulus and the fibrosis grade generally exhibited a quadratic trend. It was concluded that severity of fibrosis had a good correlation with stiffness of the liver. Results also indicated that the elasticity imaging of the liver may provide significant clinical values if the elastic modulus can be accurately measured.

Percutaneous Ethanol Injection Versus Surgical Resection for the Treatment of Small Hepatocellular Carcinoma: A Prospective Study

Objective:To compare disease recurrence and survival among patients with small hepatocellular carcinoma after surgical resection or percutaneous ethanol injection therapy, 2 treatments that have not been evaluated with a prospective study. Methods:A total of 76 patients were randomly assigned to 2 groups based on treatment; all had one or 2 tumors with diameter ≤3 cm, with hepatitis without cirrhosis or Child class A or B cirrhosis without evident ascites or bleeding tendency. Results:Follow-up ranged from 12 to 59 months. Among percutaneous injection patients, 18 had recurrence 1 to 37 months after treatment (true recurrence, 11; original safety margin inadequate, 3; limitation of imaging technology to detect tiny tumors, 4). Three injection therapy patients died of cancer 25, 37, and 57 months after treatment. For the surgical resection group, 15 had recurrence 2 to 54 months after treatment (true recurrence, 12; limitation of imaging, 2; neck metastasis, 1). Five resection patients died of cancer at 11, 20, 23, 26, and 52 months, respectively. By Cox regression model and Kaplan-Meier survival analysis, there is no statistical significance for recurrence and survival between treatment groups. However, tumor size larger than 2 cm and alpha-fetoprotein over 200 ng/mL correlated with higher recurrence rate, and Child class B liver cirrhosis correlated with shorter survival. Conclusions:Percutaneous ethanol injection therapy appears to be as safe and effective as resection, and both treatments can be considered first-line options for small hepatocellular carcinoma.

Hepatitis C and B viruses in hepatitis B Surface antigen-negative hepatocellular carcinoma

The relative role of hepatitis C virus and hepatitis B virus in hepatitis B surface antigen-negative hepatocellular carcinoma was evaluated by polymerase chain reaction in 31 patients from Taiwan. Twenty-one were positive for antibody to hepatitis C virus (group 1) and 10 were negative (group 2). Of the group 1 patients, hepatitis C viral RNA was detected in the serum by polymerase chain reaction in 16 and in the liver tissue in 17, whereas hepatitis B viral DNA was found in the liver tissue in only 4, and none were found in the serum. In group 2 patients, hepatitis C viral RNA was detected in the serum of 1 and in the liver tissue of another. In contrast, hepatitis B viral DNA was found in the serum of 4 patients and in the liver tissues of 5. It was concluded that hepatitis C virus plays an important role in hepatocarcinogenesis in hepatitis B surface antigen-negative patients in Taiwan, especially in those who had antibody to hepatitis C virus; in those without antibody to hepatitis C virus, hepatitis B virus might still be associated with the development of hepatocellular carcinoma in a significant proportion of such patients.

High-frequency microsatellite instability predicts better chemosensitivity to high-dose 5-fluorouracil plus leucovorin chemotherapy for stage IV sporadic colorectal cancer after palliative bowel resection.

The influence of MSI on treatment outcome of colorectal cancers remains unclear and deserves further investigation. We recruited 244 patients with stage IV sporadic colorectal cancers for our study, based on appropriate eligibility criteria. Patients were nonrandomly allocated to 2 treatment groups of either with or without high‐dose 5‐FU plus leucovorin chemotherapy (HDFL, 5‐FU 2,600 mg/m2 leucovorin 300 mg/m2 maximum 500 mg). Each treatment group was further divided into 2 subgroups according to high‐frequency MSI (MSI‐H) status. MSI‐H was defined as the appearance of MSI in at least 2 of the 5 examined chromosomal loci (BAT‐25, BAT‐26, D5S346, D2S123, D17S250). We compared clinicopathologic parameters, p53 overexpression and overall survival between the groups. In addition, 4 subgroups were identified as follows: MSI‐H+HDFL+, n = 35; MSI‐H−HDFL+, n = 134; MSI‐H+HDFL−, n = 17; MSI‐H−HDFL−, n = 58. There was no significant difference of background clinicopathologic data between the HDFL+ and HDFL− treatment groups (p > 0.05). Survival analyses indicated that the patients of subgroup MSI‐H+HDFL+ survived significantly longer than those of subgroup MSI‐H−HDFL+, with median survival times of 24 (95% CI 20.2–27.9) and 13 (95% CI 11.6–14.4) months, respectively (p = 0.0001, log‐rank test). In contrast, in patients without chemotherapy, the prognosis was poor irrespective of MSI status, with median survival times of 7.0 (95% CI 4.6–9.4) and 7.0 (95% CI 6.1–7.9) months in the MSI‐H+HDFL− and MSI‐H−HDFL− subgroups, respectively (p = 0.8205, log‐rank test). MSI‐H cancers responded significantly better to HDFL (p = 0.001), with a mean response rate of 65.71% (95% CI 49.98–81.44%) in subgroup MSI‐H+HDFL+ compared to 35.07% (95% CI 26.99–43.15%) in subgroup MSI‐H−HDFL+. There appeared to be no preferential metastatic site where response to HDFL can be predicted based on the MSI status of the primary tumor. Toxicity to HDFL was similarly minimal between MSI‐H+ and MSI‐H− patients (p > 0.05). Multivariate analysis of all patients further indicated that MSI‐H and chemotherapy were independent favorable prognostic parameters (p < 0.05). Thus, the better prognosis of stage IV sporadic colorectal cancers with MSI‐H may be associated with better chemosensitivity, rather than lower aggressiveness in biologic behavior.

Genome-wide DNA methylation profiles in hepatocellular carcinoma†‡

Alterations in DNA methylation frequently occur in hepatocellular cancer (HCC). We have previously demonstrated that hypermethylation in candidate genes can be detected in plasma DNA before HCC diagnosis. To identify, with a genome‐wide approach, additional genes hypermethylated in HCC that could be used for more accurate analysis of plasma DNA for early diagnosis, we analyzed tumor and adjacent nontumor tissues from 62 Taiwanese HCC cases using Illumina methylation arrays (Illumina, Inc., San Diego, CA) that screen 26,486 autosomal CpG sites. After Bonferroni adjustment, a total of 2,324 CpG sites significantly differed in methylation level, with 684 CpG sites significantly hypermethylated and 1,640 hypomethylated in tumor, compared to nontumor tissues. Array data were validated with pyrosequencing in a subset of five of these genes; correlation coefficients ranged from 0.92 to 0.97. Analysis of plasma DNA from 38 cases demonstrated that 37%‐63% of cases had detectable hypermethylated DNA (≥5% methylation) for these five genes individually. At least one of these genes was hypermethylated in 87% of the cases, suggesting that measurement of DNA methylation in plasma samples is feasible. Conclusion: The panel of methylated genes indentified in the current study will be further tested in a large cohort of prospectively collected samples to determine their utility as early biomarkers of HCC. (HEPATOLOGY 2012;55:1799–1810)

Stathmin overexpression cooperates with p53 mutation and osteopontin overexpression, and is associated with tumour progression, early recurrence, and poor prognosis in hepatocellular carcinoma.

Stathmin, a major microtubule‐depolymerizing protein, is involved in cell cycle progression and cell motility. This study aimed to elucidate its role in the progression, early tumour recurrence (ETR), and prognosis of hepatocellular carcinoma (HCC). Stathmin mRNA was overexpressed in 88/156 (56%) resected, unifocal, primary HCCs, while p53 mutation was present in 72 (46%) and osteopontin mRNA overexpression in 79 (51%). Stathmin mRNA expression exhibited high concordance (93%) with protein expression in 107 cases examined by immunohistochemistry. Stathmin overexpression correlated with high α‐fetoprotein (>200 ng/ml, p = 0.02), larger tumour size (>5 cm, p = 0.012), high tumour grade (p < 0.0002), high tumour stage (stage IIIA–IV) with vascular invasion and various degrees of intrahepatic metastasis (p < 1 × 10−8), ETR (p = 0.003), and lower 5‐year survival (p = 0.0007). Stathmin protein expression was often more intense in the peripheral regions of tumour trabeculae, tumour borders, and portal vein tumour thrombi. Stathmin overexpression correlated with p53 mutation (p = 0.017) and osteopontin overexpression (p = 1 × 10−8), both of which were associated with vascular invasion (both p < 0.0001) and poorer prognosis (p < 0.0004 and p = 0.0004, respectively). Regardless of the status of p53 mutation or osteopontin expression, stathmin overexpression was associated with higher vascular invasion (all p < 0.0001). Approximately 90% of HCCs harbouring stathmin overexpression with concomitant p53 mutation or osteopontin overexpression exhibited vascular invasion, and hence the lowest 5‐year survival, p = 0.00018 and p = 0.0009, respectively. However, we did not find that stathmin overexpression exerted prognostic impact independent of tumour stage. In conclusion, stathmin expression correlates with metastatic potential, is an important prognostic factor for HCC, and may serve as a useful marker to predict ETR. Copyright

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.

High frequency of promoter hypermethylation of RASSF1A and p16 and its relationship to aflatoxin B1-DNA adduct levels in human hepatocellular carcinoma.

Epigenetic changes in gene expression due to extensive CpG island methylation is now accepted as the main cause of inactivation of the p16 gene. More recently, it has been suggested that the human ras association domain family (RASSF) 1 gene, cloned from the lung tumor‐suppressor locus 3p21.3, also may be inactivated by methylation. It consists of two major alternative transcripts, RASSF1A and RASSF1C. Epigenetic inactivation of isoform A was observed in several carcinomas and tumor cell lines. In this study, promoter hypermethylation of RASSF1A and p16 was investigated in 83 hepatocellular carcinoma (HCC) tissue samples from Taiwan and in two HCC cell lines (Hep3B and HepG2). High frequencies (85% and 47%, respectively) of methylation of the CpG island promoters of RASSF1A and p16 were found in the HCC tissues. The methylation of RASSF1A also was detected in Hep3B cells but not in HepG2 cells; p16 was not methylated in either cell line. Methylation status was determined in 12 normal control liver tissues and 10 adjacent nontumor tissues. No methylation was found in normal liver control tissues for both RASSF1A and p16; methylation was detected in one of 10 and seven of 10 adjacent nontumor tissue sampless for p16 and RASSF1A, respectively, in subjects with positive tumors. These data indicate that aberrant methylation of the CpG island promoters of both genes is a frequent occurrence in hepatocarcinogenesis. The high frequency of RASSF1A methylation in adjacent tissues suggests that this may be an early event. The relationship between methylation status and clinical parameters and tumor markers, including DNA damage resulting from aflatoxin B1 (AFB1), an environmental carcinogen, and p53 status, also was analyzed. A statistically significant association was found between RASSF1A methylation status and the level of AFB1‐DNA adducts in tumor tissues. No association was found between methylation status and p53 status. These results suggest the hypothesis that exposure to environmental carcinogens may be involved in altered methylation of genes involved in cancer development.

Heparanase inhibitor PI-88 as adjuvant therapy for hepatocellular carcinoma after curative resection: A randomized phase II trial for safety and optimal dosage

BACKGROUND/AIMS Hepatocellular carcinoma recurrence after curative treatment adversely influences clinical outcome. It is important to explore adjuvant therapies. This phase II/stage 1 multi-center, randomized trial investigated the safety, optimal dosage and preliminary efficacy of PI-88, a novel heparanase inhibitor, in the setting of post-operative recurrence of HCC according to a Simons 2-stage design. METHODS Three groups were included: one untreated arm (Group A) and two PI-88 arms (Group B: 160 mg/day; Group C: 250 mg/day). Treatment groups received PI-88 over nine 4-week treatment cycles, followed by a 12-week treatment-free period. Safety and optimal dosage were assessed. RESULTS Overall, 172 patients were randomized and 168 were included in the intention-to-treat (ITT) population. Treatment-related adverse effects included cytopenia, injection site hemorrhage, PT prolongation, etc. Four serious adverse events were possibly related to PI-88 treatment. One (1.8%) group B patients and six (10.5%) group C had hepatotoxicity-related withdrawals. Among the ITT population, 29 patients (50%) in Group A, 35 (63%) in Group B, and 22 (41%) in Group C remained recurrence-free at completion. Calculated T(1) value suggested 160 mg/day treatment satisfied the criteria for the next stage of the trial. CONCLUSIONS PI-88 at 160 mg/day is optimal and safe, and shows preliminary efficacy as an adjunct therapy for post-operative HCC.

Gene Expression Profile Predicts Patient Survival of Gastric Cancer After Surgical Resection

PURPOSE This study was conducted to characterize gene expression profile of survival in patients with surgically curable gastric cancer by using an in-house membrane microarray and developing a survival prediction model. MATERIALS AND METHODS Data of cDNA microarrays were obtained from 18 pairs of cancerous and noncancerous gastric tissues. Nine patients who survived > 30 months were identified as good survival, and the other nine, who survived < 12 months, were identified as poor survival. Supervised analysis was performed to identify a gene expression profile by good and poor survival. Semiquantitative reverse transcriptase polymerase chain reaction (RT-PCR) was used to confirm the microarray data in 10 patients with sufficient RNA. Using these 10 patients and another 10 patients selected randomly from 40 newly enrolled patients as the training group, the RT-PCR status of the confirmed genes was used for predicting good versus poor survival. Finally, the prediction model was tested in the remaining 30 newly enrolled gastric cancer patients. RESULTS A survival prediction model consisting of three genes (CD36, SLAM, PIM-1) was developed. This model could correctly predict poor or good survival in 23 (76.7%) of 30 newly enrolled patients, and yielded a specificity of 80% and a sensitivity of 73.3%. The survival rate of the patients predicted to have good survival was significantly higher than that of those predicted to have poor survival in the test group as a whole (N = 30; P = .00531) and in stage III patients (n = 16; P = .04467). CONCLUSION The semiquantitative RT-PCR gene expression profiling of three genes extracted from microarray study can accurately predict surgery-related outcome in gastric cancer patients.