Clinicopathologic analysis of intraductal papillary neoplasm of bile duct: Korean multicenter cohort study.

BACKGROUND: IPNB is very rare disease and most previous studies on IPNB were case series with a small number due to low incidence. The aim of this study is to validate previously known clinicopathologic features of intraductal papillary neoplasm of bile duct (IPNB) based on the first largest multicenter cohort. METHODS: Among 587 patients previously diagnosed with IPNB and similar diseases from each center in Korea, 387 were included in this study after central pathologic review. We also reviewed all preoperative image data. RESULTS: Of 387 patients, 176 (45.5%) had invasive carcinoma and 21 (6.0%) lymph node metastasis. The 5-year overall survival was 80.9% for all patients, 88.8% for IPNB with mucosal dysplasia, and 70.5% for IPNB with invasive carcinoma. According to the "Jang & Kim's modified anatomical classification," 265 (68.5%) were intrahepatic, 103 (26.6%) extrahepatic, and 16 (4.1%) diffuse type. Multivariate analysis revealed that tumor invasiveness was a unique predictor for survival analysis. (p = 0.047 [hazard ratio = 2.116, 95% confidence interval 1.010-4.433]). CONCLUSIONS: This is the first Korean multicenter study on IPNB through central pathologic and radiologic review process. Although IPNB showed good long-term prognosis, relatively aggressive features were also found in invasive carcinoma and extrahepatic/diffuse type.

Cytochrome P450 4A11 expression in tumor cells: A favorable prognostic factor for hepatocellular carcinoma patients.

BACKGROUND AND AIM: Elevated cytochrome p450 (CYP) 4A gene expression has been linked to the aggravation of various cancers and affects various regulated metabolites. In hepatocellular carcinoma (HCC), the clinicopathological value of CYP4A has not yet been explored, although CYP4A is expressed at high levels in the liver. The goal of this study was to evaluate the clinicopathological value of CYP4A11 expression in HCC. METHODS: We performed immunohistochemical analysis of CYP4A11 and correlated the results with clinicopathological features of HCC (n = 155). Western blotting and reverse transcription-polymerase chain reaction against CYP4A11 and CYP4A22 were also performed for 15 and 20 pairs of fresh-frozen primary HCC and non-neoplastic liver tissue, respectively. Moreover, we analyzed the underlying mechanism by comparing the high and low CYP4A11 mRNA expression groups using gene set enrichment analysis. RESULTS: CYP4A11 expression level was higher in non-neoplastic hepatocytes than those in HCC cells (P < 0.001), and CYP4A11 expression positively correlated with favorable prognostic factors, including tumor size, histological grade, and pathological tumor stage (P = 0.007, P = 0.005, and P = 0.007). Multivariate analysis revealed that CYP4A11 expression was an independent prognostic factor of overall and disease-free survival (P = 0.002 and P = 0.033). Based on gene set enrichment analysis, high CYP4A11 mRNA expression negatively correlated with the expression of cell cycle-related genes. CONCLUSION: These findings support the notion that CYP4A11 expression is a favorable prognostic factor of HCC and suggest potential predictive diagnostic and prognostic roles of CYP4A11 expression in HCC.

Surgical strategy for T1 gallbladder cancer: a nationwide multicenter survey in South Korea.

BACKGROUND: The aim of this study was to investigate the clinical features and clinical outcomes of T1 gallbladder (GB) cancer and to determine an appropriate surgical strategy for T1 GB cancer. METHODS: A nationwide multicenter study, in which 16 University Hospitals in Korea participated, was performed from 1995 to 2004. A total of 258 patients, 117 patients with T1a and 141 patients with T1b disease were enrolled. Clinicopathologic findings and long-term follow-up results were analyzed after a consensus meeting of the Korean Pancreas Surgery Club was held. RESULTS: Simple cholecystectomy was performed in 95 patients (81.2 %) with T1a tumor and in 89 patients (63.1 %) with T1b tumor (p < 0.01). Lymph node metastasis was observed in 2.9 % of T1a patients and in 9.9 % of T1b patients (p = 0.391). A significant difference in 5-year disease-specific survival (DSS) rates was observed between T1a and T1b patients (96.4 vs 84.8 %, respectively, p = 0.03). However, no significant 5-year DSS rate difference was observed between those who underwent simple cholecystectomy or extended cholecystectomy, regardless of whether lymph node dissection was performed or whether lymph node metastasis was present. There was no significant difference in recurrence-free survival between simple cholecystectomy and extended cholecystectomy. CONCLUSIONS: There was no superiority of extended cholecystectomy over simple cholecystectomy in the aspect of survival and recurrence especially in T1b gallbladder cancer. Furthermore, the effectiveness of regional lymphadenectomy for treatment purpose remains questionable. Therefore, simple cholecystectomy could be recommended as a surgical strategy of T1 gallbladder cancer.

Microwave transmission in graphene oxide.

We investigated the radio-frequency transmission properties of reduced graphene oxide (GO) sheets including contact effects with the metal electrodes. GO sheets were prepared by dielectrophoresis and their structural characteristics were analyzed by x-ray photoelectron spectroscopy and Raman spectroscopy. The contact resistance was much higher than the intrinsic resistance over the entire frequency range, thus the contact resistance was considered as a dominant component of impedance in the radio-frequency regime. In the radio-frequency regime, GO sheets showed a drastic decrease in impedance based on a consistent decrease in the intrinsic and contact resistance. These results support the potential of GO as a radio-frequency interconnector with a solution-based fabrication method.

An ent-kaurane diterpenoid from Croton tonkinensis induces apoptosis by regulating AMP-activated protein kinase in SK-HEP1 human hepatocellular carcinoma cells.

Hepatocellular carcinoma (HCC) is the most common type of liver cancer with high mortality worldwide. Traditional chemotherapy for HCC is not widely accepted by clinical practitioners because of its toxic side effects. Thus, there is a need to identify chemotherapeutic drugs against HCC. AMP-activated protein kinase (AMPK) is a biologic sensor for cellular energy status that acts a tumor suppressor and a potential cancer therapeutic target. The traditional Vietnamese medicinal plant Croton tonkinensis shows cytotoxicity in various cancer cells; however, its anticancer mechanism remains unclear. In this study, we determined whether the ent-kaurane diterpenoid ent-18-acetoxy-7ß-hydroxy kaur-15-oxo-16-ene (CrT1) isolated from this plant plays a role as a chemotherapeutic drug targeting AMPK. CrT1 blocked proliferation in dose- and time-dependent manners in human hepatocellular carcinoma SK-HEP1 cells. CrT1 induced sub-G(1) arrest and caspase-dependent apoptosis. CrT1 activated caspase-3, -7, -8, -9, and poly(ADP-ribose) polymerase, and its effect was inhibited by z-VAD-fmk suppressing caspase-3 cleavage. CrT1 induced increases in p53 and Bax levels but decreased Bcl(2) levels. In addition, CrT1 resulted in increased translocation of cytochrome c into the cytoplasm. We showed that CrT1-activated AMPK activation was followed by modulating the mammalian target of rapamycin/p70S6K pathway and was inactivated by treating cells with compound C. Treatment with CrT1 and aminoimidazole carboxamide ribonucleotide (AICAR) synergistically activated AMPK. CrT1-induced AMPK activation regulated cell viability and apoptosis. These results suggest that CrT1 is a novel AMPK activator and that AMPK activation in SK-HEP1 cells is responsible for CrT1-induced anticancer activity including apoptosis.

Fatty acid synthase inhibition by amentoflavone suppresses HER2/neu (erbB2) oncogene in SKBR3 human breast cancer cells.

Fatty acid synthase (FASN) is a potential therapeutic target for treatment of cancer and obesity, and is highly elevated in 30% of HER2-overexpressing breast cancers. Considerable interest has developed in searching for novel FASN inhibitors as therapeutic agents in treatment of HER2-overexpressing breast cancers. Amentoflavone was found to be effective in suppressing FASN expression in HER2-positive SKBR3 cells. Pharmacological inhibition of FASN by amentoflavone specifically down-regulated HER2 protein and mRNA, and caused an up-regulation of PEA3, a transcriptional repressor of HER2. In addition, pharmacological blockade of FASN by amentoflavone preferentially decreased cell viability and induced cell death in SKBR3 cells. Palmitate reduced the cytotoxic effect of amentoflavone, as the percentage of viable cells was increased after the addition of exogenous palmitate. Amentoflavone-induced FASN inhibition inhibited the translocation of SREBP-1 in SKBR3 cells. Amentoflavone inhibited phosphorylation of AKT, mTOR, and JNK. The use of pharmacological inhibitors revealed that the modulation of AKT, mTOR, and JNK phosphorylation required synergistic amentoflavone-induced FASN inhibition and HER2 activation in SKBR3 cells. These results suggest that amentoflavone modulated FASN expression by regulation of HER2-pathways, and induced cell death to enhance chemopreventive or chemotherapeutic activity in HER2-positive breast cancers.

Lower abdominal approach in laparoscopic cholecystectomy: A propensity score-matching analysis and prospective cohort study.

BACKGROUND: Classic laparoscopic cholecystectomy) using multiple ports is a widely used method with excellent surgical outcomes. However, the resulting wounds do not meet the cosmetic needs of patients. Therefore, this study aimed to find a new minimally invasive surgical method for invisible wounds while maintaining surgical safety through a new port site. METHODS: In this prospective cohort study, we used propensity score matching analysis to evaluate the perioperative outcomes of multiport laparoscopic cholecystectomy using articulating devices with the lower abdominal approach. We performed a propensity score matching analysis of prospectively maintained data from 228 patients who underwent classic laparoscopic cholecystectomy using straight instruments and laparoscopic cholecystectomy with a lower abdominal approach using articulating devices between January and October 2022. A single surgeon performed all operations included in the study. We evaluated several perioperative outcomes. RESULTS: No differences were found in potential confounding factors, such as sex, age, admission type, previous abdominal surgery, and medical comorbidities, between the 2 groups after propensity score matching. In the classic laparoscopic cholecystectomy group, the mean operation time was shorter (43.73 ± 23.71 vs 50.60 ± 9.75 min; P < .04). No significant difference was noted in the 2 groups' numerical rating scale scores for pain, body mass index, and incidence of postoperative complications. The mean length of hospital stay was longer for patients who underwent classic laparoscopic cholecystectomy (4.27 vs 2.07 days; P = .064). The lower abdominal laparoscopic cholecystectomy group had delayed defecation after surgery. CONCLUSION: Regarding surgical outcomes and minimal invasiveness, lower abdominal laparoscopic cholecystectomy is a feasible cholecystectomy method.

Magnolol-induced apoptosis in HCT-116 colon cancer cells is associated with the AMP-activated protein kinase signaling pathway.

Colon cancer is the third most common malignancy around the world. Surgery, chemotherapy, and radiotherapy are generally used to treat colon cancer, but no effective therapy for advanced colon carcinoma is available. Therefore, there is a need to identify other therapeutic agents against this disease. Magnolol, a hydroxylated biphenyl compound present in Magnolia officinalis, exerts anticancer potential and low toxicity. Emerging evidence has suggested that activation of AMP-activated protein kinase (AMPK), a potential cancer therapeutic target is involved in apoptosis in colon cancer cells. However, the effects of magnolol on human colon cancer through activation of AMPK remain unexplored. In this study, we explored whether magnolol exerts an antiproliferative effect, and induces apoptosis in HCT-116 human colon cancer cells. Magnolol displayed several apoptotic features, including propidium iodide labeling, DNA fragmentation, and caspase-3 and poly(ADP-ribose) polymerase cleavages. We showed that magnolol induced the phosphorylation of AMPK in dose- and time-dependent manners. The selective AMPK inhibitor compound C abrogated the effect of magnolol on AMPK activation, suppression of proliferation, and caspase-3 cleavage. Magnolol downregulated expression of the antiapoptotic protein Bcl2, upregulated expression of pro-apoptotic protein p53 and Bax, and caused the release of mitochondrial cytochrome c. Magnolol-induced p53 and Bcl2 expression was abolished in the presence of compound C. Magnolol inhibited migration and invasion of HCT-116 cells through AMPK activation. These findings demonstrate that AMPK mediates the anticancer effects of magnolol through apoptosis in HCT-116 cells.

Investigation on fabrication of nanoscale patterns using laser interference lithography.

Nanoscale patterns are fabricated by laser interference lithography (LIL) using Lloyd's mirror interferometer. LIL provides a patterning technology with simple, quick process over a large area without the usage of a mask. Effects of various key parameters for LIL, with 257 nm wavelength laser, are investigated, such as the exposure dosage, the half angle of two incident beams at the intersection, and the power of the light source for generating one or two dimensional (line and dot) nanoscale structures. The uniform dot patterns over an area of 20 mm x 20 mm with the half pitch sizes of around 190, 250, and 370 nm are achieved and by increasing the beam power up to 0.600 mW/cm2, the exposure process time was reduced down to 12/12 sec for the positive photoresist DHK-BF424 (DongJin) over a bare silicon substrate. In addition, bottom anti-reflective coating (DUV-30J, Brewer Science) is applied to confirm improvements for line structures. The advantages and limitations of LIL are highlighted for generating nanoscale patterns.

Determination of malignant and invasive predictors in branch duct type intraductal papillary mucinous neoplasms of the pancreas: a suggested scoring formula.

Prediction of malignancy or invasiveness of branch duct type intraductal papillary mucinous neoplasm (Br-IPMN) is difficult, and proper treatment strategy has not been well established. The authors investigated the characteristics of Br-IPMN and explored its malignancy or invasiveness predicting factors to suggest a scoring formula for predicting pathologic results. From 1994 to 2008, 237 patients who were diagnosed as Br-IPMN at 11 tertiary referral centers in Korea were retrospectively reviewed. The patients' mean age was 63.1 ± 9.2 yr. One hundred ninty-eight (83.5%) patients had nonmalignant IPMN (81 adenoma, 117 borderline atypia), and 39 (16.5%) had malignant IPMN (13 carcinoma in situ, 26 invasive carcinoma). Cyst size and mural nodule were malignancy determining factors by multivariate analysis. Elevated CEA, cyst size and mural nodule were factors determining invasiveness by multivariate analysis. Using the regression coefficient for significant predictors on multivariate analysis, we constructed a malignancy-predicting scoring formula: 22.4 (mural nodule [0 or 1]) + 0.5 (cyst size [mm]). In invasive IPMN, the formula was expressed as invasiveness-predicting score = 36.6 (mural nodule [0 or 1]) + 32.2 (elevated serum CEA [0 or 1]) + 0.6 (cyst size [mm]). Here we present a scoring formula for prediction of malignancy or invasiveness of Br-IPMN which can be used to determine a proper treatment strategy.

Chrysophanic acid blocks proliferation of colon cancer cells by inhibiting EGFR/mTOR pathway.

Inactivation of epidermal growth factor receptor (EGFR) is a prime method used in colon cancer therapy. Here it is shown that chrysophanic acid, a natural anthraquinone, has anticancer activity in EGFR-overexpressing SNU-C5 human colon cancer cells. Chrysophanic acid preferentially blocked proliferation in SNU-C5 cells but not in other cell lines (HT7, HT29, KM12C, SW480, HCT116 and SNU-C4) with low levels of EGFR expression. Chrysophanic acid treatment in SNU-C5 cells inhibited EGF-induced phosphorylation of EGFR and suppressed activation of downstream signaling molecules, such as AKT, extracellular signal-regulated kinase (ERK) and the mammalian target of rapamycin (mTOR)/ribosomal protein S6 kinase (p70S6K). Chrysophanic acid (80 and 120 µm) significantly blocked cell proliferation when combined with the mTOR inhibitor, rapamycin. These findings offer the first evidence of anticancer activity for chrysophanic acid via EGFR/mTOR mediated signaling transduction pathway.

Feasibility of using the homologous parietal peritoneum as a vascular substitute for venous reconstruction during abdominal surgery: An animal model.

BACKGROUND: The interest in vascular substitutes has recently increased. We evaluated the feasibility of using a homologous parietal peritoneum as a vascular substitute for venous reconstruction during abdominal surgery. METHODS: The inferior vena cava was replaced with a homologous parietal peritoneum after cross-linking with glutaraldehyde in 36 rabbits. At 7, 14, and 28 days, the patency rate, outer and inner graft diameters, histology, and immunohistochemistry were evaluated. RESULTS: Both the 7- and 14-day groups maintained vascular patency. Vascular patency was maintained in 3 rabbits in the 28-day group. The inner diameters of the anastomotic sites were 6.23 ± 0.18, 5.64 ± 0.16, and 2.34 ± 0.21 mm in the 7-day, 14-day, and 28-day groups, respectively. The midpoint inner diameters of the homologous parietal peritoneum grafts were 624 ± 0.46, 5.74 ± 0.26, and 2.14 ± 0.28 mm in each group, respectively. Endothelial cell proliferation on the homologous parietal peritoneum graft surfaces in all groups was based on the histological findings from the first group. Multiple neovascularizations of the homologous parietal peritoneum graft were found in the 14- and 28-day groups, indicating neo-media formation. Acute inflammation appeared to progress to the entire layer of the homologous parietal peritoneum graft without an intraluminal thrombus, but the graft was patent in the 14-day group. In the 28-day group, 6 rabbits showed near-total occlusion and a thrombus formed in the homologous parietal peritoneum graft at the anastomosis site with severe stricture; however, the rabbits were alive and had collateral vessel formation. CONCLUSION: Using homologous parietal peritoneum is feasible for venous reconstruction in abdominal surgery.

Activation of AMP-activated protein kinase on human gastric cancer cells by apoptosis induced by corosolic acid isolated from Weigela subsessilis.

Corosolic acid is one of the triterpenoids present in the leaves of Weigela subsessilis. The antidiabetic activity of corosolic acid has been reported previously, but to date, the anticancer effects on gastric cancer have been poorly studied. In this study, corosolic acid showed growth inhibition on SNU-601 human gastric cancer cells, with an IC50 value of 16.9 ± 2.9 µM. Corosolic acid also triggered the activation of caspase-3 and poly (ADP-ribose) polymerase, while it was recovered by Z-VAD-FMK. Moreover, the cell growth/apoptosis activities of corosolic acid were regulated by the AMP-activated protein kinase-mammalian target of rapamycin (AMPK-mTOR) signals. These results showed that corosolic acid-mediated AMPK activation leads to inhibition of mTOR, thus providing a possible mechanism of action of corosolic acid in the inhibition of cancer cell growth and the induction of apoptosis.

Long-term outcome of intraoperative radiofrequency ablation for hepatocellular carcinoma and its efficacy as a primary treatment.

BACKGROUNDS/AIMS: We conducted this study to identify long-term outcomes following intraoperative radiofrequency ablation (IO-RFA) for hepatocellular carcinoma (HCC) and to reveal independent prognostic factors for survival. METHODS: From December 1998 to February 2019, 183 patients underwent IO-RFA for HCC. These patients were divided into two groups according to whether RFA was done as a first-line (1-RFA group, n=106) or secondary-line (2-RFA group, n=77) treatment. Furthermore, we compared the survival outcomes between the 1-RFA and 2-RFA groups. RESULTS: There were no significant differences in type of surgical approaches between the two groups (p=0.079). The number of tumors and largest tumor size were not significantly different between the two groups. Overall recurrence rate was 53%, and the 2-RFA group showed a higher recurrence rate (46.2% in 1-RFA group versus 62.3% in 2-RFA group; p=0.031). The 5-year overall survival (OS) and disease-free survival (DFS) rates of all the patients were 75.2% and 27.9%, respectively. The OS and DFS rates were significantly higher in the 1-RFA group. The 5-year OS rates were 83.6% and 64.9% in the 1-RFA and 2-RFA groups, respectively (p=0.010), whereas the 5-year DFS rates were 32.2% and 21.6%, respectively (p=0.012). On multivariate analysis, HBV-LC, 2-RFA, recurrence, and postoperative complications were independent predictive factors for survival. CONCLUSIONS: Therapeutic outcomes of IO-RFA were comparable to those of surgical resection. Additionally, 1-RFA might be an alternative treatment for naïve HCC in patients with uncompensated liver function and severe comorbidities.

Protein kinase SGK1 enhances MEK/ERK complex formation through the phosphorylation of ERK2: implication for the positive regulatory role of SGK1 on the ERK function during liver regeneration.

BACKGROUND/AIMS: Based on the observation of biphasic induction of SGK1 expression in the regenerating liver, we investigated the role of SGK1 in the regulation of MEK/ERK signaling pathway which plays a crucial role in regulating growth and survival signaling. METHODS: To determine the role of SGK1 in the activation of MEK/ERK signaling cascade, we infected primary hepatocytes with recombinant adenoviral vector encoding SGK1, and assessed its effect on the MEK/ERK signaling pathway. RESULTS: Partial hepatectomy resulted in the biphasic transcriptional induction of SGK1 in regenerating liver tissues. Infection of primary hepatocytes with an adenoviral vector encoding SGK1 enhanced the ERK phosphorylation under serum-starved conditions and this was blocked by the expression of kinase-dead SGK1. SGK1 was found to physically interact with ERK1/2 as well as MEK1/2. Furthermore, SGK1 mediated the phosphorylation of ERK2 on Ser(29) in a serum-dependent manner. Replacement of Ser(29) to aspartic acid, which mimics the phosphorylation of Ser(29), enhanced the ERK2 activity as well as the MEK/ERK complexes formation. CONCLUSIONS: SGK1 expression during liver regeneration is a part of a signaling pathway that is necessary for enhancing ERK signaling activation through modulating the MEK/ERK complex formation.

The appropriate surgical strategy for T1b gallbladder cancer incidentally diagnosed after a simple cholecystectomy.

BACKGROUNDS/AIMS: The appropriate surgical treatment was investigated for T1b gallbladder (GB) cancer through a retrospective analysis of the clinical outcomes of patients with incidental T1 GB cancer. METHODS: Patients with T1 GB cancer who were incidentally diagnosed while undergoing a simple cholecystectomy at Chungnam University Hospital from January 2004 to December 2017 were enrolled. Overall, 39 patients with T1 GB cancer, 17 patients with T1a, and 22 patients with T1b were included. We retrospectively analyzed the patients' clinical and pathologic findings and follow-up results. RESULTS: Among the 6490 patients who underwent cholecystectomy during the study period, 165 patients were diagnosed with GB cancer (T1=42 [25.5%]). The risk factor associated with recurrence and cancer-related death in patients with T1 GB cancer was lymphovascular invasion (recurrence, p=0.028; death, p=0.004). In the T1b group, the 5-year disease-free survival (DFS) rate showed a statistical difference between patients with and without lymphovascular invasion (45.7% vs. 83.6%, p=0.048). There was no statistically significant difference in 5-year DFS and overall survival rate between simple cholecystectomy and extended cholecystectomy in T1b GB cancer with lymphovasular invasion (p=0.054 and p=0.091, respectively). CONCLUSIONS: In incidental T1b GB cancer, extended cholecystectomy was not superior to simple cholecystectomy in terms of the 5-year DFS rate and nor in overall survival rate or recurrence rate, even when lymphovascular invasion was identified after simple cholecystectomy. Therefore, simple cholecystectomy may be recommended as a primary surgical strategy for T1b GB cancer.

High nuclear NADPH oxidase 4 expression levels are correlated with cancer development and poor prognosis in hepatocellular carcinoma.

NADPH oxidase (NOX) is a key source of reactive oxygen species (ROS). This study aimed to verify NOX2 and NOX4 expression levels in hepatocellular carcinoma (HCC). A total of 134 matched pairs of HCC cells and non-tumour hepatocytes from 134 patients were examined by immunohistochemical staining, and the association of NOX2 and NOX4 expression with clinicopathological parameters was analysed. Western blotting in four HCC cell lines and reverse transcription digital droplet polymerase chain reaction (RT-ddPCR) in 20 pairs of HCC and non-tumour tissue samples were also performed to detect NOX4. Cytoplasmic NOX2 and nuclear NOX4 expression levels were shown by immunohistochemistry to be higher in HCC cells than in non-tumour hepatocytes (p<0.001 each). The western blotting results for NOX4 in four HCC cell lines were consistent with the immunohistochemical results. Increased cytoplasmic expression of NOX2 and NOX4 in HCC cells was significantly correlated with liver cirrhosis (p<0.001 and p<0.031, respectively). However, decreased cytoplasmic expression of NOX2 and NOX4 was significantly correlated with advanced pathological TNM stage (p<0.029 and p<0.007, respectively). Multivariate analysis with clinicopathological parameters showed that high nuclear and low cytoplasmic NOX4 expression levels are correlated with short overall survival (p=0 .021). Our findings imply that cytoplasmic NOX2 and nuclear NOX4 expression is upregulated during HCC development. In particular, NOX4 translocation into the nucleus may affect the development and progression of HCC. NOX2 and NOX4 could be diagnostic markers and have therapeutic implications in HCC.

APEX1 Expression as a Potential Diagnostic Biomarker of Clear Cell Renal Cell Carcinoma and Hepatobiliary Carcinomas.

Apurinic/apyrimidinic endonuclease 1/redox effector factor 1 (APEX1) has been known to play key roles in DNA repair, the regulation of diverse transcriptional activity, and cellular responses to redox activity. This study aimed to examine serum APEX1 (s-APEX1) expression as a possible screening biomarker for clear cell renal cell carcinoma (ccRCC), hepatocellular carcinoma (HCC), and proximal and distal cholangiocarcinoma (CC). A total of 216 frozen serum samples were collected from 39 healthy control cases, 32 patients with ≥58 copies/mL of hepatitis B viral DNA (HBV DNA (+)), 40 ccRCC cases, 59 HCC cases, and 46 CC cases. The serum samples were examined for s-APEX1 concentration by enzyme-linked immunosorbent assay. The association of APEX1 expression with clinicopathological characteristics was also studied by immunohistochemical staining in 106 ccRCC, 131 HCC, and 32 intrahepatic CC cases. The median s-APEX1 concentrations of the HCC, CC, ccRCC, healthy control, and HBV DNA (+) groups were 0.294, 0.710, 0.474, 0.038, and 2.384 ng/mL, respectively (p < 0.001). Univariate and multivariate analyses revealed that increased cytoplasmic APEX1 expression led to a shorter disease-free survival period in HCC and CC cases. We suggest that the s-APEX1 level could be a potential diagnostic biomarker of ccRCC, HCC, and CC. Additionally, cytoplasmic APEX1 expression in cancer cells could be used to predict relapses in patients with HCC or CC.

Expression of antihypertensive peptide, His-His-Leu, as tandem repeats in Escherichia coli.

His-His-Leu (HHL), a tripeptide derived from a Korean soybean paste, is an angiotensin-I-converting enzyme (ACE) inhibitor. We report here a method of producing this tripeptide efficiently by expressing tandem multimers of the codons encoding the peptide in E. coli and purifying the HHL after hydrolysis of the peptide multiners. The HHL gene, tandemly multimerized to a 40-mer, was ligated with ubiquitin as a fusion gene (UH40). UH40 was inserted into vector pET29b; the UH40 fusion protein was then produced in E. coli BL21. The recombinant UH40 protein was purified by cation-exchange chromatography with a yield of 17.3 mg/l and analyzed by matrix-assisted laser desorption ionization (MALDI) time-of-flight (TOF) mass spectrometry and protein N-terminal sequencing. Leucine aminopeptidase was used to cleave a 405-Da HHL monomer from the UH40 fusion protein and the peptide was purified using reverse-phase high-performance liquid chromatography (HPLC) on a C18 HPLC column, with a final yield of 6.2 mg/l. The resulting peptide was confirmed to be HHL with the aid of MALDI-TOF mass spectrometry, glutamine-TOF mass spectrometry, N-terminal sequencing, and measurement of ACE inhibiting activity. These results suggest that our production method is useful for obtaining a large quantity of recombinant HHL for functional antihypertensive peptide studies.

Non-invasive Assessment of Liver Fibrosis with ElastPQ: Comparison with Transient Elastography and Serologic Fibrosis Marker Tests, and Correlation with Liver Pathology Results.

We investigated the feasibility of using ultrasound shear wave elastography point quantification (ElastPQ) for liver fibrosis staging and compared it with other non-invasive tools with respect to efficacy in liver stiffness measurement. A total of 106 patients who underwent liver stiffness measurements, using ElastPQ and biochemical investigations, before parenchymal liver biopsy or surgery were included. Among these, 51 also underwent transient elastography (TE). Correlations of ElastPQ, TE and aspartate aminotransferase-to-platelet ratio index (APRI) with histopathological findings (as the reference standard) were determined using Spearman's correlation coefficient. The diagnostic performance of ElastPQ, TE and APRI was evaluated using receiver operating characteristic (ROC) curve analysis. ElastPQ had good diagnostic accuracy in identifying each liver fibrosis stage, with an area under the ROC curve (AUC) of 0.810 to 0.864. Stiffness values obtained using ElastPQ, TE and APRI were significantly positively correlated (r = 0.686, r = 0.732 and r = 0.454, respectively) with histologic fibrosis staging (p < 0.001). According to the AUC for the diagnosis of significant fibrosis (≥F2) and cirrhosis (=F4), ElastPQ had better diagnostic accuracy (AUC = 0.929 and 0.834, respectively) than APRI (AUC = 0.656 and 0.618, respectively) (p < 0.05), and was similar to TE (AUC = 0.915 and 0.879, respectively). ElastPQ is a promising ultrasound-based imaging technique for evaluation of liver fibrosis, with a diagnostic accuracy comparable to that of TE.