A Multicenter, Randomized, Open-Label Study to Compare the Efficacy and Safety of Tacrolimus and Corticosteroids in Combination With or Without Mycophenolate Mofetil in Liver Transplantation Recipients Infected With Hepatitis B Virus.

BACKGROUND: Mycophenolate mofetil exhibits pharmacologic mechanisms different from calcineurin inhibitors. Therefore, the dose of calcineurin inhibitors can be reduced along with side effects for effective immunosuppression. We aimed to evaluate the efficacy and safety of tacrolimus and corticosteroid in combination with or without mycophenolate mofetil in living donor liver transplantation (LDLT) recipients infected with hepatitis B virus (HBV). METHODS: A randomized, open-label, comparative, multicenter, phase IV study was conducted with 119 patients from January 2014 to September 2017. In the full analysis set population, 58 and 59 patients were included in the study group (triple-drug regimen: TacroBell + My-rept + corticosteroid) and the control group (dual-drug regimen: TacroBell + corticosteroid), respectively. In the per protocol set population, 49 and 42 patients were included in the study and control groups, respectively. RESULTS: In the full analysis set population, the incidence of biopsy-proven acute cellular rejection (rejection activity index score ≥4) was 3.4% in the study group; however, this finding was not observed in the control group (P = .468). Hepatitis B virus recurrence was observed in one patient in the control group. No cases of biopsy-proven acute cellular rejection and HBV recurrence were observed in the per protocol set population. The incidences of serious adverse events were 25.9% and 18.0% in the study and control groups, respectively; however, the difference between the groups was not statistically significant (P = .376). CONCLUSION: Although the study involved a small number of patients, the triple-drug regimen can be considered safe and effective for immunosuppression after living donor liver transplantation in patients infected with HBV.

Effect of CYP3A5 on the Once-Daily Tacrolimus Conversion in Stable Liver Transplant Patients.

Cytochrome P450 (CYP) 3A5 polymorphism influences tacrolimus metabolism, but its effect on the drug pharmacokinetics in liver transplant recipients switched to once-daily extended-release formulation remains unknown. The aim of this study is to analyze the effect of CYP3A5 polymorphism on liver function after once-daily tacrolimus conversion in liver transplant patients. A prospective open-label study included 60 stable liver transplant recipients who underwent 1:1 conversion from twice-daily tacrolimus to once-daily tacrolimus. All participants were genotyped for CYP3A5 polymorphism. The study was registered at ClinicalTrials.gov (NCT02882113). Twenty-eight patients were enrolled in the CYP3A5 expressor group and 32 in the non-expressor group. Although there was no statistical difference, incidence of liver dysfunction was higher in the expressor group than in the non-expressor group when converted to once-daily extended-release tacrolimus (p = 0.088). No biopsy-proven acute rejection, graft failure, and mortality were observed in either group. The decrease in dose-adjusted trough level (-42.9% vs. -26.1%) and dose/kg-adjusted trough level of tacrolimus (-40.0% vs. -23.7%) was significantly greater in the expressor group than in the non-expressors after the conversion. A pharmacokinetic analysis was performed in 10 patients and tacrolimus absorption in the non-expressor group was slower than in the expressor group. In line with this observation, the area under the curve for once-daily tacrolimus correlated with trough level (Cmin) in the non-expressors and peak concentration (Cmax) in the expressors. CYP3A5 genotyping in liver transplant recipients leads to prediction of pharmacokinetics after switching from a twice-daily regimen to a once-daily dosage form, which makes it possible to establish an appropriate dose of tacrolimus.

A Randomized Phase II Study of Perioperative Chemotherapy Plus Bevacizumab Versus Postoperative Chemotherapy Plus Bevacizumab in Patients With Upfront Resectable Hepatic Colorectal Metastases.

INTRODUCTION: Whether patients with resectable colorectal liver metastases (CRLM) gain a survival benefit from perioperative chemotherapy remains controversial. The benefit of including bevacizumab in chemotherapy also remains unclear. MATERIAL AND METHODS: Seventy-six patients with CRLM were randomly assigned to either 6 cycles of FOLFOX (folinic acid, 5-fluorouracil, and oxaliplatin)/FOLFIRI (folinic acid, 5-fluorouracil, and irinotecan) with bevacizumab before and after surgery or 12 cycles after surgery. Progression-free survival (PFS) was estimated using the Kaplan-Meier method and compared by the log-rank test. RESULTS: The median PFS of all patients was 37.4 months at 5.4 years follow-up, and the median overall survival (OS) was not reached. The PFS between the perioperative group and the postoperative group did not reveal a statistical difference (P = .280). The OS was significantly better in the perioperative group (hazard ratio [HR], 0.60; 95% confidence interval [CI],) 0.35-1.02; P = .049). In subgroup patients with carcinoembryonic antigens (CEA) ≥ 5 ng/mL or those with over 2 liver metastases, perioperative group had longer OS than postoperative group (CEA: HR, 0.49; 95% CI, 0.25-0.93; P = .030; number of liver metastases: HR, 0.55; 95% CI, 0.30-0.99; P = .049). The largest liver metastases size, disease-free interval, and sidedness did not affect PFS or OS. There was no difference between the 2 groups in postoperative complications with bevacizumab or adverse events during chemotherapy. CONCLUSIONS: In patients with resectable CRLMs, perioperative chemotherapy had no effect on PFS, but improved OS. Patients with high CEA levels or over 2 liver metastases may benefit from perioperative chemotherapy.

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.

Diamond-shaped patch technique for right hepatic vein reconstruction in living-donor liver transplant: A simple method to prevent stenosis.

Patency of the right hepatic vein (RHV) of the liver graft is essential for successful living-donor liver transplant (LDLT). We developed a simple technique for RHV reconstruction that does not require the use of cadaveric veins or additional time to prevent stenosis.Of 159 patients who underwent LDLT at our institution between May 2010 and April 2016, we included 152 in this study. Conventional RHV reconstruction was performed in 100 patients, while the diamond-shaped patch (D-patch) technique was performed in 53. For the D-patch technique, the posterior aspect of the RHV needs to be dissected from the liver parenchyma during donor hepatectomy, which prevents stenosis due to liver rotation after graft regeneration. A D-patch obtained from the hepatic vein of the recipient liver was used on the anterior aspect of the RHV for reconstruction. The Student's t test and χ test were used for statistical analysis.Rates of intervention for RHV stenosis during the first month were significantly different between the conventional reconstruction and D-patch groups (19.2% vs 3.8%; P = .01). The time taken to perform the D-patch technique was similar to that for conventional reconstruction (anhepatic period, 104.9 ±â€Š47.3 minutes vs 106.7 ±â€Š42.0 minutes; P = .82).The D-patch technique for RHV reconstruction in LDLT is a simple, fast, and feasible surgical technique that can be performed without using cadaveric or saphenous veins.

Enhanced Photosensing and Photodynamic Treatment of Colon Cancer Cells Using Methoxy Poly(ethylene glycol)-Conjugated Chlorin e6.

Nanophotosensitizer composed of methoxy poly(ethylene glycol) (MePEG) and chlorin e6 (Ce6) (abbreviated as Pe6) was synthesized for efficient delivery of Ce6 to the colon cancer cells. Pe6 nanophotosensitizer has small diameter less than 100 nm with spherical shape and core-shell structure. They were activated in aqueous solution while Ce6 was quenched due to its poor aqueous solubility. They showed no intrinsic cytotoxicity against normal cells and colon cancer cells. Pe6 nanophotosensitizers showed enhanced cellular uptake, phototoxicity, and reactive oxygen species (ROS) generation at in vitro cell culture experiment. Furthermore, they showed improved tumor tissue penetration and accumulation in vivo animal studies. We suggested Pe6 nanophotosensitizers as an ideal candidate for PDT of colon cancer.

Predictors of postoperative infectious complications in liver transplant recipients: experience of 185 consecutive cases.

Background/Aims: Infections following liver transplant (LT) remain a major cause of mortality. This study was conducted to evaluate risk factors for infection and to review clinical characteristics. METHODS: Medical records of patients who underwent LT from 2010 to 2014 were retrospectively analyzed. Binary logistic regression analysis was used to investigate risk factors of infection. Kaplan-Meier analysis was used to predict prognosis of infected and non-infected groups. RESULTS: Of 185 recipients, 89 patients experienced infectious complications. The median follow-up period was 911 days (range, 9 to 2,031). The infected group had higher 1-year mortality (n = 22 [24.7%] vs. n = 8, [8.3%], p = 0.002), and longer postoperative admission days (mean: 53.7 ± 35.8 days vs. 28.3 ± 13.0 days, p < 0.001), compared to the non-infected group. High preoperative Model for End-Stage Liver Disease (MELD) score (odds ratio [OR], 1.057; 95% confidence interval [CI], 1.010 to 1.105; p = 0.016), deceased-donor type (OR, 5.475; 95% CI, 2.442 to 12.279; p < 0.001), and acute rejection (OR, 3.042; 95% CI, 1.241 to 7.454; p = 0.015) were independent risk factors associated with infection. Intra-abdominal infection (n = 35, 20.8%) was the major infectious complication. Among identified bacteria, Enterococcus species (28.4%) were major pathogens, followed by Escherichia coli and Klebsiella species. Conclusions: High preoperative MELD score, deceased-donor type, and acute rejection were risk factors associated with infection. To prevent infections following surgery, it is important to determine the appropriate time of operation before the recipient has a high MELD score.

Risk factors of early recurrence after curative hepatectomy in hepatocellular carcinoma.

Early recurrence is common after curative hepatectomy for hepatocellular carcinoma and is associated with poor prognosis. This study aimed to identify risk factors of early recurrence after curative hepatectomy in hepatocellular carcinoma. Overall, 63 patients who underwent curative hepatectomy for hepatocellular carcinoma were enrolled. Patients were divided into the early recurrence group, who developed recurrence within 12 months after hepatectomy (n = 10), and the non-early recurrence group (n = 53). Clinicopathological factors of early recurrence were retrospectively analyzed. Among the 63 patients, 10 (15.9%) patients experienced early recurrence. Univariate analysis showed tumor necrosis (p = 0.012), level of PIVKA-II (prothrombin induced by vitamin K absence or antagonist-II; p = 0.002), and microvascular invasion (p = 0.029) to be associated with early recurrence. By multivariate analysis, there were significant differences in high PIVKA-II (p < 0.001) and tumor necrosis (p = 0.012) in patients with early recurrence. The optimal cutoff values of PIVKA-II and tumor necrosis were 46 mAU/mL and 3% of total tumor volume, respectively. Patients with a high preoperative PIVKA-II level and extent of tumor necrosis, which are independent risk factors for early recurrence, should be actively treated and monitored closely after hepatectomy.

Clinical Impacts of Donor Types of Living vs. Deceased Donors: Predictors of One-Year Mortality in Patients with Liver Transplantation.

Transplantation studies about the clinical differences according to the type of donors are mostly conducted in western countries with rare reports from Asians. The aims of this study were to evaluate the clinical impacts of the type of donor, and the predictors of 1-year mortality in patients who underwent liver transplantation (LT). This study was performed for liver transplant recipients between May 2010 and December 2014 at the Pusan National University Yangsan Hospital. A total of 185 recipients who underwent LT were analyzed. Of the 185 recipients, 109 (58.9%) belonged to the living donor liver transplantation (LDLT) group. The median age was 52.4 years. LDLT recipients had lower model for end-stage liver disease (MELD) score compared with better liver function than deceased donor liver transplantation (DDLT) recipients (mean ± standard deviation [SD], 12.5 ± 8.3 vs. 24.9 ± 11.7, respectively; P < 0.001), and had more advanced hepatocellular carcinoma (HCC) (62.4% vs. 21.1%, respectively; P = 0.001). In complications and clinical outcomes, LDLT recipients showed shorter stay in intensive care unit (ICU) (mean ± SD, 10.8 ± 8.8 vs. 23.0 ± 13.8 days, respectively, P < 0.001), ventilator care days, and post-operative admission days, and lower 1-year mortality (11% vs. 27.6%, respectively, P = 0.004). Bleeding and infectious complications were less in LDLT recipients. Recipients with DDLT (P = 0.004) showed higher mortality in univariate analysis, and multi-logistic regression analysis found higher MELD score and higher pre-operative serum brain natriuretic peptide (BNP) were associated with 1-year mortality. This study may guide improved management before and after LT from donor selection to post-operation follow up.

Do hepatic-sided tumors require more extensive resection than peritoneal-sided tumors in patients with T2 gallbladder cancer? Results of a retrospective multicenter study.

BACKGROUND: Tumor location is a prognostic factor for survival in patients with T2 gallbladder cancer. However, the optimal extent of resection according to tumor location remains unclear. METHODS: We reviewed the records of 192 patients with T2 gallbladder cancer who underwent R0 or R1 resection at 6 institutions. Perioperative and oncologic outcomes were compared according to the extent of resection between hepatic-sided (n = 93) and peritoneal-sided (n = 99) tumors. RESULTS: After a median follow-up of 30 months, the 5-year overall survival (84.9% vs 71.8%, P = .048) and recurrence-free survival (74.6% vs 62.2%, P = .060) were greater in peritoneal-sided T2 patients than in hepatic-sided T2 patients. Among hepatic-sided T2 patients, the 5-year overall survival was greater in patients who underwent radical cholecystectomy including lymph node dissection with liver resection than in patients who underwent lymph node dissection without liver resection (80.3% vs 30.0%, P = .032), and the extent of liver resection was not associated with overall survival (P = .526). Lymph node dissection without liver resection was an independent prognostic factor for overall survival in hepatic-sided T2 gallbladder cancer (hazard ratio 5.009, 95% confidence interval 1.512-16.596, P = .008). In peritoneal-sided T2 patients, the 5-year overall survival was not significantly different between the lymph node dissection with liver resection and the lymph node dissection without liver resection subgroups (70.5% vs 54.8%, P = .111) and the extent of lymph node dissection was not associated with overall survival (P = .395). CONCLUSION: In peritoneal-sided T2 gallbladder cancer, radical cholecystectomy including lymph node dissection without liver resection is a reasonable operative option. Radical cholecystectomy including lymph node dissection with liver resection is suitable for hepatic-sided T2 gallbladder cancer.

Increasing use of therapeutic apheresis as a liver-saving modality.

INTRODUCTION: Therapeutic plasma exchange (TPE) is used for temporary support of liver function in patients presenting with early graft dysfunction after liver transplantation (LT) or liver surgery. We analyzed the effect of therapeutic apheresis on patients with liver disease. METHODS: Between January 2011 and August 2016, 93 apheresis procedures were performed for 26 patients at our institution. Anti-ABO isoagglutination immunoglobulin (Ig) M titer was checked using a type A and type B 3% red blood cell (RBC) suspension in saline with two-fold serial dilutions of patient serum. Anti-ABO isoagglutination IgG titer was checked by a type A and B 0.8% RBC suspension using a low-ionic strength/Coombs card. RESULTS: ABO-incompatible (ABOi) LT was the most common (n=10, 38.5%) indication for apheresis; early graft dysfunction after LT (n=8, 30.7%) was the second most common. Median initial IgM and IgG anti-ABO titers for ABOi LT recipients were 1:16 (range, 1:8-1:128) and 1:48 (range, 1:8-1:2048). We performed preoperative TPE in 10 recipients (median number of sessions, 1.5; range, 1-11). Among patients with early graft dysfunction, those who underwent living donor LT had better survival (4/4; 100%) than those who underwent nonliving donor LT (0/3; 0%). Patients who underwent living donor LT first and then additional LT also survived after three TPE sessions. CONCLUSION: Therapeutic apheresis is associated with a good survival rate and is essential for liver support in patients with early graft dysfunction after LT or posthepatectomy liver failure and during preparation for ABOi LT.

Donor safety in living donor liver transplantation: The Korean organ transplantation registry study.

Major concerns about donor safety cause controversy and limit the use of living donor liver transplantation to overcome organ shortages. The Korean Organ Transplantation Registry established a nationwide organ transplantation registration system in 2014. We reviewed the prospectively collected data of all 832 living liver donors who underwent procedures between April 2014 and December 2015. We allocated the donors to a left lobe group (n = 59) and a right lobe group (n = 773) and analyzed the relations between graft types and remaining liver volumes and complications (graded using the Clavien 5-tier grading system). The median follow-up was 19 months (range, 10-31 months). During the study period, 553 men and 279 women donated livers, and there were no deaths after living liver donation. The overall, biliary, and major complication (grade ≥ III) rates were 9.3%, 1.7%, and 1.9%, respectively. The graft types and remaining liver volume were associated with significantly different overall, biliary, and major complication rates. Of the 16 patients with major complications, 9 (56.3%) involved biliary complications (2 biliary strictures [12.5%] and 7 bile leakages [43.8%]). Among the 832 donors, the mean aspartate transaminase, alanine aminotransferase, and total bilirubin levels were 23.9 ± 8.1 IU/L, 20.9 ± 11.3 IU/L, and 0.8 ± 0.4 mg/dL, respectively, 6 months after liver donation. In conclusion, biliary complications were the most common types of major morbidity in living liver donors. Donor hepatectomy can be performed successfully with minimal and easily controlled complications. Our study shows that prospective, nationwide cohort data provide an important means of investigating the safety in living liver donation. Liver Transplantation 23 999-1006 2017 AASLD.

Clinical usefulness of controlled attenuation parameter to screen hepatic steatosis for potential donor of living donor liver transplant.

OBJECTIVE: Hepatic steatosis is associated with an increased risk of graft loss. Although the controlled attenuation parameter (CAP), a process based on transient elastography, has been suggested as a noninvasive method of assessing hepatic steatosis, to date, there is no study on the usefulness of CAP as a single screening tool for detecting hepatic steatosis in potential living donor liver. We evaluated the accuracy of CAP for detecting hepatic steatosis in potential liver donors. PATIENTS AND METHODS: All potential donors of living-donor liver transplantation who underwent a CAP assessment and ultrasonography-guided liver biopsy were enrolled. The steatosis grades were as follows: S0 less than 5%; S1, 5-33%; S2, 34-66%; and S3, more than 66%. RESULTS: According to the liver biopsies, 19 (34.5%) patients had S0, 30 (54.5%) patients had S1, and 6 (11.0%) patients had S2. The CAP value was correlated positively with BMI (r=0.242, P=0.01), waist circumference (r=0.268, P=0.006), hip circumference (r=0.334, P=0.001), Magnetic resonance fat signal fraction (r=0.465, P=0.001), and histologic steatosis grade (r=0.542, P=0.001). The area under the receiver operator characteristic curve for the diagnosis of steatosis (≥S2) by CAP was 0.88 (sensitivity 83.3% and specificity 81.6% at a cutoff value of 276 dB/m, P<0.0001). CONCLUSION: This study suggests that CAP, as a simple and noninvasive preoperative assessment for hepatic steatosis, may be sufficient for identifying and thus excluding significant hepatic steatosis (>33%) in potential liver donors.

Pancreas Transplant with Duodeno-Duodenostomy and Caval Drainage Using a Diamond Patch Graft: A Single-Center Experience.

BACKGROUND The surgical technique used in pancreas transplant is essential for patient safety and graft survival, and problems exist with conventional strategies. When enteric exocrine drainage is performed, there is no method of immunologic monitoring other than direct graft pancreas biopsy. The most common cause of early graft failure is graft thrombosis, and adequate preventive and treatment strategies are unclear. To overcome these disadvantages, we suggest a modified surgical technique. MATERIAL AND METHODS Eleven patients underwent pancreas transplant with our modified technique. The modified surgical techniques are as follows: 1) graft duodenum was anastomosed with recipient duodenum to enable endoscopic immunological monitoring, and 2) the inferior vena cava was chosen for vascular anastomosis and a diamond-shaped patch was applied to prevent graft thrombosis. RESULTS No patient mortality or graft failure occurred. One case of partial thrombosis of the graft portal vein occurred, which did not affect graft condition, and resolved after heparin treatment. All patients were cured from diabetes mellitus. There were no cases of pancreatic rejection, but 2 cases of graft duodenal rejection occurred, which were adequately treated with steroid therapy. CONCLUSIONS This modified surgical technique for pancreas transplant represents a feasible method for preventing thrombosis and allows for direct graft monitoring through endoscopy.

Efficacy and patency of primary stenting for hepatic venous outflow obstruction after living donor liver transplantation.

BACKGROUND: Hepatic venous outflow is important for graft survival in living donor liver transplantation (LDLT). If hepatic venous outflow obstruction occurs, hepatic vein stenting is considered to restore the patency. PURPOSE: To retrospectively evaluate the efficacy and patency of primary hepatic vein stenting for hepatic venous outflow obstruction (HVOO) after LDLT. MATERIAL AND METHODS: Percutaneous interventions, including hepatic vein stent placement with or without balloon angioplasty, were performed in 21 patients who had undergone LDLT and had HVOO confirmed through hepatic venography or manometry, including the patients who had a structural abnormality. Two stents each were inserted in four patients; therefore, the total number of treated anastomoses was 25. Technical success, patency rates, and pressure gradients between hepatic veins and the right atrium were evaluated in 19 patients each. RESULTS: Technical success was achieved in 25 of 26 vessels (96%). The mean interval between operation and stenting was 43 days. After the procedure, the follow-up period was a mean 530 days. The mean pressure gradient decreased from 8.5 mmHg to 2.1 mmHg after treatment (P < 0.01). The patency rates of the 25 vessels were 80% at 1, 2, and 3 years after stent placement. However, middle hepatic vein stenting revealed a low patency rate (all were 36%). Three of seven stents (43%) in the middle hepatic vein occluded during follow-up. CONCLUSION: Percutaneous primary hepatic vein stent replacement is an effective treatment for HVOO after LDLT.

Therapeutic efficacy and stent patency of transhepatic portal vein stenting after surgery.

AIM: To evaluate portal vein (PV) stenosis and stent patency after hepatobiliary and pancreatic surgery, using abdominal computed tomography (CT). METHODS: Percutaneous portal venous stenting was attempted in 22 patients with significant PV stenosis (> 50%) - after hepatobiliary or pancreatic surgery - diagnosed by abdominal CT. Stents were placed in various stenotic lesions after percutaneous transhepatic portography. Pressure gradient across the stenotic segment was measured in 14 patients. Stents were placed when the pressure gradient across the stenotic segment was > 5 mmHg or PV stenosis was > 50%, as observed on transhepatic portography. Patients underwent follow-up abdominal CT and technical and clinical success, complications, and stent patency were evaluated. RESULTS: Stent placement was successful in 21 patients (technical success rate: 95.5%). Stents were positioned through the main PV and superior mesenteric vein (n = 13), main PV (n = 2), right and main PV (n = 1), left and main PV (n = 4), or main PV and splenic vein (n = 1). Patients showed no complications after stent placement. The time between procedure and final follow-up CT was 41-761 d (mean: 374.5 d). Twenty stents remained patent during the entire follow-up. Stent obstruction - caused by invasion of the PV stent by a recurrent tumor - was observed in 1 patient in a follow-up CT performed after 155 d after the procedure. The cumulative stent patency rate was 95.7%. Small in-stent low-density areas were found in 11 (55%) patients; however, during successive follow-up CT, the extent of these areas had decreased. CONCLUSION: Percutaneous transhepatic stent placement can be safe and effective in cases of PV stenosis after hepatobiliary and pancreatic surgery. Stents show excellent patency in follow-up abdominal CT, despite development of small in-stent low-density areas.

Paclitaxel-incorporated nanoparticles using block copolymers composed of poly(ethylene glycol)/poly(3-hydroxyoctanoate).

Block copolymers composed of poly(3-hydroxyoctanoate) (PHO) and methoxy poly(ethylene glycol) (PEG) were synthesized to prepare paclitaxel-incorporated nanoparticle for antitumor drug delivery. In a (1)H-NMR study, chemical structures of PHO/PEG block copolymers were confirmed and their molecular weight (M.W.) was analyzed with gel permeation chromatography (GPC). Paclitaxel as a model anticancer drug was incorporated into the nanoparticles of PHO/PEG block copolymer. They have spherical shapes and their particle sizes were less than 100 nm. In a (1)H-NMR study in D2O, specific peaks of PEG solely appeared while peaks of PHO disappeared, indicating that nanoparticles have core-shell structures. The higher M.W. of PEG decreased loading efficiency and particle size. The higher drug feeding increased drug contents and average size of nanoparticles. In the drug release study, the higher M.W. of PEG block induced the acceleration of drug release rate. The increase in drug contents induced the slow release rate of drug. In an antitumor activity study in vitro, paclitaxel nanoparticles have practically similar anti-proliferation activity against HCT116 human colon carcinoma cells. In an in vivo animal study using HCT116 colon carcinoma cell-bearing mice, paclitaxel nanoparticles have enhanced antitumor activity compared to paclitaxel itself. Therefore, paclitaxel-incorporated nanoparticles of PHO/PEG block copolymer are a promising vehicle for antitumor drug delivery.

Self-assembled polymeric micelles based on hyaluronic acid-g-poly(D,L-lactide-co-glycolide) copolymer for tumor targeting.

Graft copolymer composed hyaluronic acid (HA) and poly(D,L-lactide-co-glycolide) (PLGA) (HAgLG) was synthesized for antitumor targeting via CD44 receptor of tumor cells. The carboxylic end of PLGA was conjugated with hexamethylenediamine (HMDA) to have amine end group in the end of chain (PLGA-amine). PLGA-amine was coupled with carboxylic acid of HA. Self-assembled polymeric micelles of HAgLG have spherical morphologies and their sizes were around 50-200 nm. Doxorubicin (DOX)-incorporated polymeric micelles were prepared by dialysis procedure. DOX was released over 4 days and its release rate was accelerated by the tumoric enzyme hyaluronidase. To assess targetability of polymeric micelles, CD44-positive HepG2 cells were employed treated with fluorescein isothiocyanate (FITC)-labeled polymeric micelles. HepG2 cells strongly expressed green fluorescence at the cell membrane and cytosol. However, internalization of polymeric micelles were significantly decreased when free HA was pretreated to block the CD44 receptor. Furthermore, the CD44-specific anticancer activity of HAgLG polymeric micelles was confirmed using CD44-negative CT26 cells and CD44-positive HepG2 cells. These results indicated that polymeric micelles of HaLG polymeric micelles have targetability against CD44 receptor of tumor cells. We suggest HAgLG polymeric micelles as a promising candidate for specific drug targeting.

Regular exercise training increases the number of endothelial progenitor cells and decreases homocysteine levels in healthy peripheral blood.

Endothelial progenitor cells (EPCs) are known to play an important role in the repair of damaged blood vessels. We used an endothelial progenitor cell colony-forming assay (EPC-CFA) to determine whether EPC numbers could be increased in healthy individuals through regular exercise training. The number of functional EPCs obtained from human peripheral blood-derived AC133 stem cells was measured after a 28-day regular exercise training program. The number of total endothelial progenitor cell colony-forming units (EPC-CFU) was significantly increased compared to that in the control group (p=0.02, n=5). In addition, we observed a significant decrease in homocysteine levels followed by an increase in the number of EPC-CFUs (p=0.04, n=5), indicating that the 28-day regular exercise training could increase the number of EPC colonies and decrease homocysteine levels. Moreover, an inverse correlation was observed between small-endothelial progenitor cell colony-forming units (small-EPC-CFUs) and plasma homocysteine levels in healthy men (r=-0.8125, p=0.047). We found that regular exercise training could increase the number of EPC-CFUs and decrease homocysteine levels, thus decreasing the cardiovascular disease risk in men.