Positional advantages of supine MRI for diagnosis prior to breast­conserving surgery.

The present study aimed to evaluate the rate of positive surgical margins for magnetic resonance imaging (MRI) performed in the supine position prior to breast-conserving surgery (BCS). The rate of positive surgical margins and the clinicopathological factors were examined in consecutive patients with BCS who underwent preoperative MRI performed in the supine position at Sapporo Medical University Hospital (Sapporo, Japan) and related hospitals and clinics between January 2012 and December 2013. Of 1,175 eligible patients, 1,150 were included after excluding 25 patients with either bilateral breast cancer or stage IV disease. Positive margin was defined as no cancer seen on the resected margin. The primary endpoint was the rate of positive surgical margins when preoperative MRI was performed in the supine position and the secondary endpoint was identification of the factors that predict positive margins. Of the 1,150 female patients (median age, 55 years; range, 29-97 years) who underwent BCS for breast cancer following MRI performed in the supine position, 215 (18.8%) had positive margins, which is similar to the rate with MRI in the prone position, and 930 (81.2%) had negative margins. The rate of positive surgical margins in patients of the human epidermal growth factor receptor 2 (HER2) type was significantly higher than that in the non-HER2 type group (6.5 and 2.9%; χ2 P=0.0103). There was no increase in the rate of positive margins in breast cancers with a diameter of >T2. The rate of positive surgical margins following MRI performed in the supine position was 18.8%. Supine MRI appears to be suitable for informing on the extent of resection of breast cancer.

Synergistic antitumor effect of histone deacetylase class IIa inhibitor with lenvatinib in hepatocellular carcinoma.

BACKGROUND: Histone deacetylase (HDAC) class I and IIa are highly expressed in hepatocellular carcinoma (HCC) and associated with decreased survival. However, clinically used pan and class I inhibitors have serious adverse events. In this study, we assessed the antitumor effects and tolerability of class IIa HDAC inhibitor (HDACI) with lenvatinib, which is a standard therapy for HCC. METHODS AND RESULT: Combination therapy with class IIa HDACI and lenvatinib exerted synergistic antitumor effect in human HCC cell lines. In mouse models, this therapy showed significant antitumor effects, and few adverse events occurred. In immunoblotting, the expression of fibroblast growth factor receptor 4 (FGFR4) and fibroblast growth factor 19 (FGF19) was high in cell lines that showed a high antitumor effect. In addition, class IIa HDACI administration decreased the expression of FGFR4. In the small interfering RNA (siRNA) analysis, knockdown of HDAC9, which is an isoform of HDAC class IIa, reduced the expression of FGFR4 and induced apoptosis. Immunohistochemistry of human clinical specimens showed a positivity rate of 32% for FGFR4 and 84% for HDAC9 in HCC, and all FGFR4-positive patients were HDAC9 positive. CONCLUSION: Class IIa HDACI and lenvatinib combination therapy induces apoptosis by downregulating FGFR4 and blocking the FGFR signaling in FGFR4-positive HCC cell lines and has demonstrated synergistic antitumor effects and safety. This combination therapy overcomes the problems of conventional therapies and will be beneficial for FGFR4-positive HCC patients.

Recent evidence for subcutaneous drains to prevent surgical site infections after abdominal surgery: A systematic review and meta-analysis.

BACKGROUND: Surgical site infections (SSIs) increase mortality, hospital stays, additional medical treatment, and medical costs. Subcutaneous drains prevent SSIs in gynecological and breast surgeries; however, their clinical impact in abdominal surgery remains unclear. AIM: To investigate whether subcutaneous drains were beneficial in abdominal surgery using a systematic review and meta-analysis. METHODS: The database search used PubMed, MEDLINE, and the Cochrane Library. The following inclusion criteria were set for the systematic review: (1) Randomized controlled trial studies comparing SSIs after abdominal surgery with or without subcutaneous drains; and (2) Studies that described clinical outcomes, such as SSIs, seroma formation, the length of hospital stays, and mortality. RESULTS: Eight studies were included in this meta-analysis. The rate of total SSIs was significantly lower in the drained group (54/771, 7.0%) than in the control group (89/759, 11.7%), particularly in gastrointestinal surgery. Furthermore, the rate of superficial SSIs was slightly lower in the drained group (31/517, 6.0%) than in the control group (49/521, 9.4%). No significant differences were observed in seroma formation between the groups. Hospital stays were shorter in the drained group than in the control group. CONCLUSION: Subcutaneous drains after abdominal surgery prevented SSIs and reduced hospital stays but did not significantly affect seroma formation. The timing of drain removal needs to be reconsidered in future studies.

Association between Hepatic Oxidative Stress Related Factors and Activation of Wnt/ß-Catenin Signaling in NAFLD-Induced Hepatocellular Carcinoma.

We investigated the association between iron overload, oxidative stress (8-oxo-7,8-dihydroguanine: 8-oxo-dG scores), Wnt/ß-catenin pathway activation (expression of glutamine synthetase: GS), and tumor hyperintensity in the Gd-EOB-DTPA-enhanced MRI hepatobiliary phase (relative enhancement ratio: RER). This was a retrospective analysis of 94 hepatocellular carcinoma (HCC) patients who underwent surgical resection. In HBV-, HCV-, and alcohol-associated HCC, serum ferritin levels in the high and low RER groups were equivalent. In contrast, ferritin levels were elevated in the 'high RER' group of patients with nonalcoholic fatty liver disease (NAFLD)-HCC. As predictors of GS positivity, high RER had a sensitivity of 57.2% and a specificity of 100%. High serum ferritin had a sensitivity of 85.7% and a specificity of 85.7%. All cases with serum ferritin ≥275.5 ng/mL and high RER were 8-oxo-dG- and iron staining-positive. Additionally, GS positivity was seen in all cases with "serum ferritin levels above the upper limits or iron staining-positive" and '8-oxo-dG high' cases. Therefore, combining serum ferritin levels with RER may increase the accuracy with which activated Wnt/ß-catenin signaling is predicted in NAFLD-HCC. We suggest that 8-oxo-dG accumulates following increased oxidative stress due to hepatic tissue iron deposition; this may activate Wnt/ß-catenin signaling and trigger carcinogenesis.

An Optimal Timing for Removing a Drain After Breast Surgery: A Systematic Review and Meta-Analysis.

BACKGROUND: In clinical practice, drains had been routinely used for reducing seroma formation after breast surgery. However, an optimal timing to remove drains does not identify yet. METHODS: This study aimed to compare the clinical outcome, such as seroma formation, surgical site infection (SSI), and a length of hospital stay between early removal and late removal. A systematic review was performed using PubMed, MEDLINE, and the Cochrane Library. Breast cancer patients who received surgery using drains were eligible. Those parameters were compared between early vs late removal. RESULTS: Eleven studies included in this meta-analysis. Seroma formation in the early removal group was significantly higher than the one in the late removal group (RR = 1.58: 95%CI [1.25-2.01], P = 0.0001), meanwhile no significant difference was found among the groups for SSI (RR = 0.82: 95%CI [0.51-1.31], P= 0.40). A length of hospital stay in the early removal group was also significantly shorter than late removal (RR -3.31: 95%CI [-5.13-1.49], P = 0.0004). CONCLUSIONS: Seroma formation was significantly higher in patients who had early drain removal. Conversely, SSI incidence was low, and early removal did not increase SSI incidence. In conclusion, early drain removal has no proved clinical benefit in these settings besides reduction of hospital stays.

Extracellular vesicles containing miR-146a-5p secreted by bone marrow mesenchymal cells activate hepatocytic progenitors in regenerating rat livers.

BACKGROUND: Small hepatocyte-like progenitor cells (SHPCs) appear to form transient clusters in rat livers treated with retrorsine (Ret) and 70% partial hepatectomy (PH). We previously reported that the expansion of SHPCs was amplified in Ret/PH-treated rat livers transplanted with Thy1+ cells derived from D-galactosamine-treated injured livers. Extracellular vesicles (EVs) produced by hepatic Thy1+ donor cells activated SHPCs via interleukin (IL)-17 receptor B signaling. As bone marrow-derived mesenchymal cells (BM-MCs) also express Thy1, we aimed to determine whether BM-MCs could also promote the growth of SHPCs. METHODS: BM-MCs were isolated from dipeptidyl-peptidase IV (DPPIV)-positive rats. BM-MCs or BM-MC-derived EVs were administered to DPPIV-negative Ret/PH rat livers, and the growth and the characteristics of SHPC clusters were evaluated 14 days post-treatment. miRNA microarrays and cytokine arrays examined soluble factors within EVs. Small hepatocytes (SHs) isolated from an adult rat liver were used to identify factors enhancing hepatocytic progenitor cells growth. RESULTS: The recipient's livers were enlarged at 2 weeks post-BM-MC transplantation. The number and the size of SHPCs increased remarkably in livers transplanted with BM-MCs. BM-MC-derived EVs also stimulated SHPC growth. Comprehensive analyses revealed that BM-MC-derived EVs contained miR-146a-5p, interleukin-6, and stem cell factor, which could enhance SHs' proliferation. Administration of EVs derived from the miR-146a-5p-transfected BM-MCs to Ret/PH rat livers remarkably enhanced the expansion of SHPCs. CONCLUSIONS: miR-146a-5p involved in EVs produced by BM-MCs may play a major role in accelerating liver regeneration by activating the intrinsic hepatocytic progenitor cells.

The Japan Society for Surgical Infection: guidelines for the prevention, detection, and management of gastroenterological surgical site infection, 2018.

BACKGROUND: The guidelines for the prevention, detection, and management of gastroenterological surgical site infections (SSIs) were published in Japanese by the Japan Society for Surgical Infection in 2018. This is a summary of these guidelines for medical professionals worldwide. METHODS: We conducted a systematic review and comprehensive evaluation of the evidence for diagnosis and treatment of gastroenterological SSIs, based on the concepts of the Grading of Recommendations Assessment, Development and Evaluation (GRADE) system. The strength of recommendations was graded and voted using the Delphi method and the nominal group technique. Modifications were made to the guidelines in response to feedback from the general public and relevant medical societies. RESULTS: There were 44 questions prepared in seven subject areas, for which 51 recommendations were made. The seven subject areas were: definition and etiology, diagnosis, preoperative management, prophylactic antibiotics, intraoperative management, perioperative management, and wound management. According to the GRADE system, we evaluated the body of evidence for each clinical question. Based on the results of the meta-analysis, recommendations were graded using the Delphi method to generate useful information. The final version of the recommendations was published in 2018, in Japanese. CONCLUSIONS: The Japanese Guidelines for the prevention, detection, and management of gastroenterological SSI were published in 2018 to provide useful information for clinicians and improve the clinical outcome of patients.

Association between preoperative tumor necrosis factor alpha inhibitor and surgical site infection after surgery for inflammatory bowel disease: a systematic review and meta-analysis.

Tumor necrosis factor-alpha inhibitor (TNFi) treatment is effective for ulcerative colitis (UC) and Crohn's disease (CD). Although several meta-analyses have been performed to evaluate the association between TNFi treatment and surgical morbidity, the results are controversial. We conducted a systematic review and meta-analysis of the prevention of surgical site infection (SSI) after surgery for UC and CD in patients on TNFis, based on literature published between January 2000 and May 2019 (registered on PROSPERO, No. CRD42019134156). Overall, 2175 UC patients in 13 observational studies (OBSs) and 7084 CD patients in 16 OBSs were included. The incidences of incisional (INC) SSI and organ/space (O/S) SSI after surgery for UC were 179/1985 (9.0%) and 176/2175 (8.1%), respectively. TNFi use was not associated with the incidences of INC SSI (odds ratio (OR) 1.04, 95% confidence interval (CI) (0.47-2.32) or O/S SSI (OR 1.85, 95% CI (0.82-4.20)) after surgery for UC. The INC SSI and O/S SSI incidences after surgery for CD were 289/3089 (9.4%) and 526/7,084 (7.4%), respectively. Preoperative TNFi use was not associated with INC SSI (OR 0.98, 95% CI (0.52-1.83)) or O/S SSI incidence (OR 1.09, 95% CI (0.78-1.52)) after surgery for CD. We did not find a significant association between preoperative TNFi use and SSI in surgery for UC or CD.

Immunohistological analysis of pancreatic carcinoma after vaccination with survivin 2B peptide: Analysis of an autopsy series.

Immune checkpoint inhibitors (ICIs) have revolutionized the treatment of cancer by providing new options in addition to existing therapies. However, peptide vaccination therapies still represent an attractive approach, because of the antigen specificity. We identified survivin 2B peptide (SVN-2B), a 9-mer antigenic peptide encoded by survivin, and an SVN-2B peptide vaccine-based phase II randomized clinical trial targeting unresectable and refractory pancreatic carcinoma was undertaken. The SVN-2B peptide vaccine did not have any statistically significant clinical benefits in that study. Therefore, we undertook an autopsy study to analyze the immune status of the pancreatic cancer lesions at the histological level. Autopsies were carried out in 13 patients who had died of pancreatic cancer, including 7 who had received SVN-2B peptide vaccination and 6 who had not, as negative controls. The expression of immune-related molecules was analyzed by immunohistochemical staining. Cytotoxic T lymphocytes were analyzed by tetramer staining and enzyme-linked immunospot assay. Histological analysis revealed dense infiltration of CD8+ T cells in some lesions in patients who had received the SVN-2B peptide vaccine. A high rate of programmed cell death ligand 1 expression in cancer cells was observed in these cases, indicating that CTLs were induced by SVN-2B peptide vaccination and had infiltrated the lesions. The lack of a significant antitumor effect was most likely attributable to the expression of immune checkpoint molecules. These findings suggest that the combination of a tumor-specific peptide vaccine and an ICI might be a promising approach to the treatment of pancreatic carcinoma in the future.

Randomized phase II trial of survivin 2B peptide vaccination for patients with HLA-A24-positive pancreatic adenocarcinoma.

The prognosis of advanced pancreatic adenocarcinoma is still extremely poor. This study sought to determine the efficacy of, and immunological response to, peptide vaccination therapy in patients with this disease. In this multicenter randomized phase II study, patients with advanced pancreatic adenocarcinoma after gemcitabine and/or tegafur/gimeracil/oteracil were randomly assigned to 3 groups that each received a 2-step treatment course. In Step 1, the groups received treatments of: (i) survivin 2B peptide (SVN-2B) plus interferon-ß (IFNß); (ii) SVN-2B only; or (iii) placebo until the patients show progression. In Step 2, all patients who consented to participate received 4 treatments with SVN-2B plus IFNß. The primary endpoint was progression-free survival (PFS) after initiation of Step 1 treatment. Secondary endpoints included immunological effects assessed by analysis of PBMCs after Step 1. Eighty-three patients were randomly assigned to receive SVN-2B plus IFNß (n = 30), SVN-2B (n = 34), or placebo (n = 19). No significant improvement in PFS was observed. Survivin 2B-specific CTLs were found to be increased in the SVN-2B plus IFNß group by tetramer assay. Among patients who participated in Step 2, those who had received SVN-2B plus IFNß in Step 1 showed better overall survival compared with those who had received placebo in Step 1. Patients vaccinated with SVN-2B plus IFNß did not have improved PFS, but showed significant immunological reaction after vaccination. Subgroup analysis suggested that a longer SVN-2B plus IFNß vaccination protocol might confer survival benefit. (Clinical trial registration number: UMIN 000012146).

Quality assessment using EQ-5D-5L after lung surgery for non-small cell lung cancer (NSCLC) patients.

OBJECTIVES: Aim of this study was to elucidate an alteration of quality of life (QOL) score before and after video-assisted thoracoscopic surgery (VATS) for non-small cell lung cancer (NSCLC) patients using the 5-level EuroQol-5D questionnaire (EQ-5D-5L). We also investigated how the preoperative QOL scores affected the postoperative clinical outcome prospectively. METHODS: Between July 2018 and December 2018, 24 consecutive NSCLC patients who underwent VATS were recruited. The EQ-5D-5L for Japanese was used with face-to-face interviews to estimate the utility values of QOL. RESULTS: QOL scores were significantly declined after surgery (0.81 ± 0.19 vs. 0.74 ± 0.11: P = 0.049). The levels of EQ-5D-5L questionnaire were not significantly different before and after surgery except Q4 (pain control). The levels of Q4 were significantly worsened after surgery (1.33 ± 0.56 vs. 1.88 ± 0.61, P < 0.001). Operation time and bleeding in the preoperative low-QOL score group (N = 13) was longer (215.4 ± 52.3 min. vs. 173.5 ± 42.3 min., respectively: P = 0.045) and more (116.2 ± 152.7 ml vs. 22.7 ± 20.1 ml, respectively: P = 0.049) than those in the high-QOL score group (N = 11). CONCLUSIONS: QOL survey for lung cancer patients using EQ-5D-5L is simple and useful to identify the issue facing at the medical team. Preoperative low QOL score could be a predicting factor for the longer operation time and more bleeding.

Central pancreatectomy in portal annular pancreas for metastatic renal cell carcinoma: a case report.

BACKGROUND: Portal annular pancreas (PAP) is a rare congenital anatomical abnormality of the pancreas in which the portal vein is encircled by aberrant parenchyma, and special attention is needed for pancreatic resections. This is the first report of central pancreatectomy (CP) in a PAP for metastatic renal cell carcinoma (RCC). CASE PRESENTATION: A 76-year-old man who had a history of left nephrectomy for renal cancer not otherwise specified 36 years earlier and radical cystectomy for bladder cancer 4 years earlier was incidentally found to have a pancreatic tumor and a liver tumor. The pancreatic tumor was diagnosed as metastasis of clear cell RCC, and the liver tumor was diagnosed as moderately differentiated hepatocellular carcinoma (HCC) on preoperative histological evaluation. Preoperative computed tomography imaging showed a type 3A PAP, in which the main pancreatic duct (MPD) ran ventral to the portal vein (anteportal type), and the aberrant parenchyma was located cranial to the confluence of the portal vein and splenic vein (suprasplenic type). After adhesiotomy and partial liver resection, CP was performed. With intraoperative ultrasound guidance, the aberrant parenchyma of the PAP could be preserved, avoiding additional resection. Thus, two pancreatic transections were performed, creating a single-cut margin that contained the MPD in the distal pancreas. Oncologically safe margins were confirmed by intraoperative pathological diagnosis. The distal pancreas was reconstructed by pancreatojejunostomy in the routine procedures. The pathological diagnosis of the surgical specimens was identical to the preoperative diagnosis. A postoperative pancreatic fistula (POPF) developed from the proximal stump of the head of the pancreas, necessitating no specific treatment other than drainage. The patient showed no signs or symptoms of recurrent RCC or abnormal pancreatic function for 2 years after the operation, although a histologically proven new HCC lesion developed distant from the initial site 8 months after the operation. CONCLUSIONS: Precise preoperative evaluation of the tumor features and PAP allowed adequate surgical strategies to be planned. Intraoperative ultrasound was useful to minimize parenchymal resections of the PAP. CP is still a challenging procedure in terms of the development of POPF.

Current status of projects for developing cancer-related clinical practice guidelines in Japan and recommendations for the future.

BACKGROUND: The current status and adoption of cancer-related clinical practice guidelines in Japan has not been elucidated yet. The purpose of this study was to propose roles and suggestions to develop future cancer-related clinical guidelines. METHODS: A questionnaire consisting of four domains with a total of 17 questions was developed. We distributed the questionnaire to 28 specific academic organizations in Japan which have developed any cancer-related clinical practice guidelines and which were funded by the Ministry of Health, Labor, and Welfare. RESULTS: Most organizations have investigated nationwide dissemination and adoption of clinical practice guidelines. The rate of adoption in clinical practice was estimated at approximately ≥ 70%. However, organizations with smaller budgets reported surveying approximately 60% of the time, whereas the ones with larger budgets reported approximately 100% success in surveying about their guidelines. The presidents of the organizations agreed that a new organization operated directly by the national government was necessary. CONCLUSION: In Japan, to develop cancer-related clinical practice guidelines, a study of clinical validation is necessary. Sufficient funds must be available to support the project to maintain and revise the guidelines. Furthermore, legal and ethical issues should be solved before establishing any registry system.

Case report: Long-term survival of a pancreatic cancer patient immunized with an SVN-2B peptide vaccine.

A 62-year-old woman who underwent surgery to treat pancreatic cancer provided written, informed consent to undergo adjuvant therapy with gemcitabine, tegafur, and uracil. However, this was stopped after only 14 days due to Grade 4 neutropenia. She was then started on vaccine therapy with Survivin 2B peptide (SVN-2B) including IFA and INF-α. Although metastatic lung tumors were identified and resected at 82 months after surgery, the patient has remained free of new or relapsed disease for 12 years thereafter. Tetramer and ELISPOT assays revealed the continuous circulation of SVN-2B-restricted cytotoxic T-lymphocytes (CTLs) in her peripheral blood, and CTL clones had specific activity for SVN-2B at 12 years after surgery. The adverse effects of the peptide vaccination were tolerable and comprised low-grade headache, nausea, and fatigue. A prognosis beyond 10 years in the face of pancreatic cancer with distant metastasis is extremely rare. This experience might indicate the value of cancer vaccination therapy.

The Efficacy of Antimicrobial-Coated Sutures for Preventing Incisional Surgical Site Infections in Digestive Surgery: a Systematic Review and Meta-analysis.

BACKGROUND: Antimicrobial-coated sutures have recently become well known for preventing surgical site infections (SSIs). However, the evidence and recommendations from some organizations remain controversial. Therefore, we conducted a systematic review and meta-analysis to analyze the efficacy of antimicrobial-coated sutures for preventing SSIs in digestive surgery. METHODS: We performed a systematic review of literature published from 2000 to 2017 (registered on PROSPERO, No. CRD42017076780). We included studies defined as randomized controlled trials (RCTs) and observational studies (OBSs) for the prevention of SSIs and the reduction in hospital stay length associated with digestive surgery. RESULTS: In the 10 RCTs, the incidence rates of incisional SSIs were 160/1798 (8.9%) with coated sutures and 205/1690 (12.1%) with non-coated sutures. Overall, antimicrobial-coated sutures were superior for reducing the incidence of incisional SSI (risk ratio (RR) 0.67, 95% confidence intervals (CI) 0.48-0.94, p = 0.02) in RCTs for digestive surgery with the mixed wound class and surgeries limited to a clean-contaminated wound (RR 0.66, 95% CI 0.44-0.98, p = 0.04). A superior effect of antimicrobial-coated sutures was found in 9 RCTs that involved only colorectal surgeries (RR 0.69, 95% CI 0.49-0.98, p = 0.04). The mean hospital stay length was similar with coated or uncoated sutures in 5 RCTs involving colorectal surgery (mean difference (MD) - 5.00, 95% CI 16.68-6.69, p = 0.4). CONCLUSION: Antimicrobial-coated sutures are significantly more efficacious for preventing SSIs during digestive and colorectal surgery, even when restricted to clean-contaminated wounds. However, the hospital stay length was not affected.

Current status of the prognostic molecular biomarkers in breast cancer: A systematic review.

Biomarkers that facilitate the prediction of breast cancer prognosis can improve the quality of life in patients during the long period of illness and treatment. Particularly in recent years, with the advent of a more exhaustive analysis of genetic information and gene products, the molecular mechanisms at play during breast cancer have gradually become clearer. In the present study, a systematic review of the literature between 2009 and 2014 was conducted by searching for the keywords 'breast cancer', 'biomarkers', 'diagnosis', 'prognosis' and 'drug response' to clarify the present state of knowledge regarding biomarkers. In the final analysis, 16 studies on biomarkers for the breast cancer prognosis were retrieved. From these, 7 biomarkers in 9 studies were found to be strongly reliable predictors of prognosis and a further 7 biomarkers in 7 studies were poorly reliable. The use of these prognostic biomarkers should increase the options available for treatment algorithms.

Hepatocytic parental progenitor cells of rat small hepatocytes maintain self-renewal capability after long-term culture.

The liver has a variety of functions for maintaining homeostasis, and hepatocytes play a major role. In contrast with the high regenerative capacity of mature hepatocytes (MHs) in vivo, they have not been successfully expanded ex vivo. Here we demonstrate that CD44-positive cells sorted from small hepatocyte (SH) colonies derived from a healthy adult rat liver can proliferate on a Matrigel-coated dish in serum-free chemically defined medium; in addition, a subpopulation of the cells can divide more than 50 times in a period of 17 weeks every 4-week-passage. The passage cells retained the capability to recover highly differentiated functions, such as glycogen storage, CYP activity and bile secretion. When Matrigel-treated cells from the third passage were transplanted into retrorsine/partial hepatectomy-treated rat livers, the cells engrafted to differentiate into MHs and cholangiocytes. These results suggest that long-term cultured CD44+ SHs retain hepatocytic characteristics in vitro and the capability to differentiate into hepatocytes and cholangiocytes in vivo. Thus, a newly identified subpopulation of MHs possessing the attributes of hepatocytic stem/progenitor cells can be passaged several times without losing hepatocytic characteristics.

ST6GALNAC1 plays important roles in enhancing cancer stem phenotypes of colorectal cancer via the Akt pathway.

Colorectal cancer (CRC) is a mortal disease due to treatment resistance, recurrence and distant metastasis. Emerging evidence has revealed that a small sub-population of cancer cells termed cancer stem cells (CSCs)/ cancer-initiating cells (CICs) is endowed with high levels of tumor-initiating ability, self-renewal ability and differentiation ability and is responsible for treatment resistance, recurrence and distant metastasis. Eradication of CSCs/CICs is essential to improve current treatments. However, the molecular mechanisms by which CSCs/CICs are maintained are still elusive. In this study, we aimed to determine the molecular mechanisms by which colorectal (CR)-CSCs/CICs in are maintained human primary CRC cells. CR-CSCs/CICs were isolated by sphere-culture and the ALDEFLUOR assay, and transcriptome analysis revealed that the gene ST6 N-Acetylgalactosaminide Alpha-2,6-Sialyltransferase 1 (ST6GALNAC1) was expressed at high levels in CR-CSCs/CICs. Overexpression of ST6GALNAC1 enhanced the expression of sialyl-Tn (STn) antigen, which is carried by the CSC marker CD44, and increased the sphere-forming ability and resistance to a chemotherapeutic reagent. The opposite phenomena were observed by gene knockdown using siRNA. Furthermore, the Akt pathway was activated in ST6GANAC1-overexpressed cells, and activation of the pathway was cancelled by gene knockdown of galectin-3. The results indicate that ST6GALNAC1 has a role in the maintenance of CR-CSCs/CICs by activating the Akt pathway in cooperation with galectin-3 and that ST6GalNAC1 (or STn antigen) might be a reasonable molecule for CSC/CIC-targeting therapy.

Transplantation of Thy1+ Cells Accelerates Liver Regeneration by Enhancing the Growth of Small Hepatocyte-Like Progenitor Cells via IL17RB Signaling.

Small hepatocyte-like progenitor cells (SHPCs) transiently form clusters in rat livers treated with retrorsine (Ret)/70% partial hepatectomy (PH). When Thy1+ cells isolated from d-galactosamine-treated rat livers were transplanted into the livers of Ret/PH-treated rats, the mass of the recipient liver transiently increased during the first 30 days after transplantation, suggesting that liver regeneration was enhanced. Here we addressed how Thy1+ cell transplantation stimulates liver regeneration. We found that the number and size of SHPC clusters increased in the liver at 14 days after transplantation. GeneChip analysis revealed that interleukin 17 receptor b (IL17rb) expression significantly increased in SHPCs from livers transplanted with Thy1+ cells. We subsequently searched for ligand-expressing cells and found that sinusoidal endothelial cells (SECs) and Kupffer cells expressed Il17b and Il25, respectively. Moreover, extracellular vesicles (EVs) separated from the conditioned medium of Thy1+ cell culture induced IL17b and IL25 expression in SECs and Kupffer cells, respectively. Furthermore, EVs enhanced IL17rb expression in small hepatocytes (SHs), which are hepatocytic progenitor cells; in culture, IL17B stimulated the growth of SHs. These results suggest that Thy1-EVs coordinate IL17RB signaling to enhance liver regeneration by targeting SECs, Kupffer cells, and SHPCs. Indeed, the administration of Thy1-EVs increased the number and size of SHPC clusters in Ret/PH-treated rat livers. Sixty days post-transplantation, most expanded SHPCs entered cellular senescence, and the enlarged liver returned to its normal size. In conclusion, Thy1+ cell transplantation enhanced liver regeneration by promoting the proliferation of intrinsic hepatic progenitor cells via IL17RB signaling. Stem Cells 2017;35:920-931.

Outcomes after resection of occupational cholangiocarcinoma.

BACKGROUND: Cholangiocarcinoma caused by exposure to 1,2-dichloropropane and/or dichloromethane is recognized as occupational cholangiocarcinoma. The aim of this study was to investigate the outcomes after resection of occupational cholangiocarcinoma to establish a treatment strategy for this disease. METHODS: Clinicopathological findings and outcomes after surgical intervention in 20 patients with occupational cholangiocarcinoma were investigated. RESULTS: Of 20 the patients, curative resection was performed in 16 patients. Three patients underwent radiation at the stump of the bile ducts. Adjuvant chemotherapy was performed in 12 patients. Biliary intraepithelial neoplasia, intraductal papillary neoplasm of the bile duct, and/or chronic bile duct injury was detected in most subjects. Intraabdominal infection developed after surgery in nine patients. Cholangiocarcinoma recurred in 12 of the 20 patients. The recurrent tumors in five patients developed at a different part of the bile duct from the primary tumor and a second resection was performed in four of these five patients. CONCLUSIONS: The incidence of postoperative complications including intraabdominal infection was high in patients with occupational cholangiocarcinoma. Multicentric recurrence occurred not infrequently after surgery because the bile ducts had a high potential for the development of carcinoma. The aggressive treatment including second resection for the multicentric recurrence appeared to be effective.