Improvement of the therapeutic capacity of insulin-producing cells trans-differentiated from human liver cells using engineered cell sheet

BACKGROUND

Although pancreatic islet transplantation therapy is ideal for diabetes patients, several hurdles have prevented it from becoming a standard treatment, including donor shortage and low engraftment efficacy. In this study, we prepared insulin-producing cells trans-differentiated from adult human liver cells as a new islet source. Also, cell sheet formation could improve differentiation efficiency and graft survival.

METHODS

Liver cells were expanded in vitro and trans-differentiated to IPCs using adenovirus vectors carrying human genes for PDX1, NEUROD1, and MAFA. IPCs were seeded on temperature-responsive culture dishes to form cell sheets. Differentiation efficiency was confirmed by ß cell-specific gene expression, insulin production, and immunohistochemistry. IPC suspension was injected by portal vein (PV), and IPC sheet was transplanted on the liver surface of the diabetic nude mouse. The therapeutic effect of IPC sheet was evaluated by comparing blood glucose control, weight gain, histological evaluation, and hepatotoxicity with IPC injection group. Also, cell biodistribution was assessed by in vivo/ex vivo fluorescence image tagging.

RESULTS

Insulin gene expression and protein production were significantly increased on IPC sheets compared with those in IPCs cultured on conventional culture dishes. Transplanted IPC sheets displayed significantly higher engraftment efficiency and fewer transplanted cells in other organs than injected IPCs, and also lower liver toxicity, improved blood glucose levels, and weight gain. Immunohistochemical analyses of liver tissue revealed positive staining for PDX1 and insulin at 1, 2, and 4 weeks after IPC transplantation.

CONCLUSIONS

In conclusion, cell sheet formation enhanced the differentiation function and maturation of IPCs in vitro. Additionally, parameters for clinical application such as distribution, therapeutic efficacy, and toxicity were favorable. The cell sheet technique may be used with IPCs derived from various cell sources in clinical applications.

Risk Factors for Recurrence in Pancreatic Neuroendocrine Tumor and Size as a Surrogate in Determining the Treatment Strategy: A Korean Nationwide Study

INTRODUCTION

The prognostic factors of pancreatic neuroendocrine tumor (PNET) are unclear, and the treatment guidelines are insufficient. This study aimed to suggest a treatment algorithm for PNET based on risk factors for recurrence in a large cohort.

METHODS

Data of 918 patients who underwent curative intent surgery for PNET were collected from 14 tertiary centers. Risk factors for recurrence and survival analyses were performed.

RESULTS

The 5-year disease-free survival (DFS) rate was 86.5%. Risk factors for recurrence included margin status (R1, hazard ratio [HR] 2.438; R2, HR 3.721), 2010 WHO grade (G2, HR 3.864; G3, HR 7.352), and N category (N1, HR 2.273). A size of 2 cm was significant in the univariate analysis (HR 8.511) but not in the multivariate analysis (p = 0.407). Tumor size was not a risk factor for recurrence, but strongly reflected 2010 WHO grade and lymph node (LN) status. Tumors ≤2 cm had lower 2010 WHO grade, less LN metastasis (p < 0.001), and significantly longer 5-year DFS (77.9 vs. 98.2%, p < 0.001) than tumors >2 cm. The clinicopathologic features of tumors <1 and 1-2 cm were similar. However, the LN metastasis rate was 10.3% in 1-2-cm sized tumors and recurrence occurred in 3.0%. Tumors <1 cm in size did not have any LN metastasis or recurrence.

DISCUSSION/CONCLUSION

Radical surgery is needed in suspected LN metastasis or G3 PNET or tumors >2 cm. Surveillance for <1-cm PNETs should be sufficient. Tumors sized 1-2 cm require limited surgery with LN resection, but should be converted to radical surgery in cases of doubtful margins or LN metastasis.

Spheroid Fabrication Using Concave Microwells Enhances the Differentiation Efficacy and Function of Insulin-Producing Cells via Cytoskeletal Changes

Pancreatic islet transplantation is the fundamental treatment for insulin-dependent diabetes; however, donor shortage is a major hurdle in its use as a standard treatment. Accordingly, differentiated insulin-producing cells (DIPCs) are being developed as a new islet source. Differentiation efficiency could be enhanced if the spheroid structure of the natural islets could be recapitulated. Here, we fabricated DIPC spheroids using concave microwells, which enabled large-scale production of spheroids of the desired size. We prepared DIPCs from human liver cells by trans-differentiation using transcription factor gene transduction. Islet-related gene expression and insulin secretion levels were higher in spheroids compared to those in single-cell DIPCs, whereas actin–myosin interactions significantly decreased. We verified actin–myosin-dependent insulin expression in single-cell DIPCs by using actin–myosin interaction inhibitors. Upon transplanting cells into the kidney capsule of diabetic mouse, blood glucose levels decreased to 200 mg/dL in spheroid-transplanted mice but not in single cell-transplanted mice. Spheroid-transplanted mice showed high engraftment efficiency in in vivo fluorescence imaging. These results demonstrated that spheroids fabricated using concave microwells enhanced the engraftment and functions of DIPCs via actin–myosin-mediated cytoskeletal changes. Our strategy potentially extends the clinical application of DIPCs for improved differentiation, glycemic control, and transplantation efficiency of islets.

Predictors of early recurrence following a curative resection in patients with a carcinoma of the ampulla of Vater

Purpose

Ampulla of Vater (AoV) carcinoma has a relatively good prognosis. The 5-year recurrence rate for AoV is still around 40%–50% however, and most recurrences occur in the early period. The aim of this study was to identify predictors of an early recurrence in AoV patients following a curative resection.

Methods

The clinicopathological data for 501 consecutive patients that underwent a resection for AoV in our institute between January 2000 and December 2015 were retrospectively reviewed. The characteristics of any recurrences and early recurrence patients were analyzed accordingly. Early recurrence was defined as occurring within one year of resection.

Results

There were 170 diagnosed recurrences in our study population, 57.1% of whom were men, with a mean age of 60.1 years (range, 30–94 years). Almost all of the study patients underwent a pancreaticoduodenectomy, and 9% underwent minimally invasive surgery. Of the 170 recurrent cases, 107 were diagnosed with an early recurrence and had 1-, 3-, and 5-year overall survival rates of 77.7%, 18.4%, 10.5%, respectively. The factors that significantly influenced early recurrences, determined by multivariate analysis, lymphovascular invasion (LVI), lymph node ratio (LNR), and poor differentiation were found to be independent determinants of a recurrence within 1 year.

Conclusion

An early recurrence in AoV patients is ultimately lethal even though this cancer has a good prognosis. LVI, LNR, and poor differentiation are powerful predictors of an early recurrence in AoV. Hence, intensive surveillance and new therapeutic strategies should be considered for AoV patients with these predictors following a curative resection.

Adjuvant Chemotherapy for Resected Ampulla of Vater Carcinoma: Retrospective Analysis of 646 Patients

PURPOSE

This study evaluated the efficacy of adjuvant chemotherapy (AC) in patients with resected ampulla of Vater (AoV) carcinoma.

Materials and Methods

Data from 646 patients who underwent surgical resection at Asan Medical Center between 2000 and 2017 were retrospectively reviewed.

RESULTS

The median age of the patients was 62 years, and 54.2% were male. Patients were classified into AC group (n=165, 25.5%) and no AC group (n=481, 74.5%). With a median follow-up duration of 88 months, in patients with stage I, II, III, median recurrence-free survival (RFS) was not reached, 44 months, and 15 months, respectively, and the median overall survival (OS) were not reached, 88 months and 35 months, respectively. Despite no statistical significance, RFS and OS were better in stage II patients with AC than in those without AC (median RFS, 151 months vs. 38 months; p=0.156 and median OS, 153 months vs. 74 months; p=0.299). In multivariate analysis for RFS and OS, TNM stage, R1 resection status, presence of lymphovascular invasion, and perineural invasion remained significant factors, whereas AC (hazard ratio [HR], 0.74; 95% confidence interval [CI], 0.54 to 1.00; p=0.052) was marginally related with RFS. After propensity score matching in only stage II/III patients, RFS and OS with AC were numerically longer than those without AC (HR, 0.80; 95% CI, 0.60 to 1.06; p=0.116 and HR, 0.77; 95% CI, 0.56 to 1.06; p=0.111).

CONCLUSION

AC with fluoropyrimidine did not improve survival of patients with resected AoV carcinoma. However, multivariate analysis with prognostic factors showed a marginally significant survival benefit with AC.

A comparison of minimally invasive vs open distal pancreatectomy for resectable pancreatic ductal adenocarcinoma: Propensity score matching analysis

BACKGROUND

Owing to concerns regarding adequate oncological outcomes and perioperative complications, minimally invasive distal pancreatectomy (MIDP) for pancreatic ductal adenocarcinoma (PDAC) has limited generalizability. The aim of this study was to assess the perioperative and oncologic outcomes of MIDP compared with open distal pancreatectomy (ODP) for resectable PDAC after propensity score matching (PSM).

METHODS

The patients who underwent MIDP and ODP for PDAC between January 2010 and December 2017 were retrospectively reviewed. Demographics, perioperative outcomes, pathological outcomes, and overall and disease-free survival data were collected to compare MIDP and ODP. After PSM, perioperative and oncologic outcomes were analyzed.

RESULTS

A total of 156 MIDP patients were compared with 156 ODP patients for resectable PDAC after PSM. Tumor size, TNM stage, differentiation, harvested lymph nodes, and positive lymph nodes were not different except for R1 resection and lymphovascular invasion between the MIDP and ODP groups. Operation times, overall complications, POPF, and adjuvant treatment were also not different between the two groups. The MIDP group had shorter hospital stays (10.0 vs 13.4 days, P < 0.001) and shorter interval times from surgery to adjuvant treatment (37.6 days vs 46.0 days, P = 0.002) than the ODP group. The MIDP group had better overall survival (34.9 vs 24.5 months, P = 0.012) and disease-free survival (16.2 vs 10.3 months, P = 0.001).

CONCLUSION

Minimally invasive distal pancreatectomy has advantages with respect to postoperative hospital stay, interval between surgery, and adjuvant treatment. MIDP is associated with the possibility of improved survival rate for resectable PDAC.

Assessment of learning curve and oncologic feasibility of robotic pancreaticoduodenectomy: A propensity score-based comparison with open approach

BACKGROUND

Though robotic pancreaticoduodenectomy(R-PD) is gradually adopted, learning curve and its feasibility is still controversial. We analyzed our first 70 R-PD cases, comparing surgical outcomes and feasibility to those of open pancreaticoduodenectomy (O-PD).

METHODS

Medical records of 70 patients of R-PD and 269 patients of O-PD between 2015 and 2019 were retrospectively analyzed. Cumulative sum analysis was used to determine learning curve. Surgical outcomes were compared between early(1-35) and late cases(36-70). Additional analyses with O-PD using propensity score-matching were done.

RESULTS

Learning curve of R-PD completed after 30 cases. Shorter operative time, lower estimated blood loss, and shorter length of stay were noted in later cases. Complication rate tended to decrease over time. In comparison with O-PD after matching, R-PD showed longer operation time(414.5 minutes vs 244.7 minutes; P < .001), with no differences in estimated blood loss, or length of stay. While overall complication rate was higher in R-PD(45.5% vs 21.8%; P = .010), no statistically significant difference was observed in major complication rates(23.6% vs 10.9%; P = .084). R0 rate was equivalent.

CONCLUSION

Surgical performance of R-PD improved over time. Learning curve of R-PD completed after 30 cases. R-PD is a promising modality, based on comparison of perioperative and oncologic feasibilities to those of O-PD.

FOLFIRINOX in borderline resectable and locally advanced unresectable pancreatic adenocarcinoma

BACKGROUND

Despite the scarcity of data based on randomized trials, FOLFIRINOX is widely used in the management of borderline resectable pancreatic cancer (BRPC) and locally advanced unresectable pancreatic cancer (LAPC). We investigated the clinical outcomes of neoadjuvant FOLFIRINOX in patients with BRPC and LAPC.

METHODS

This single-center retrospective analysis included a total of 199 consecutive patients with BRPC or LAPC who received conventional or modified FOLFIRINOX between February 2013 and January 2017. An independent radiologist reviewed all baseline computed tomography or magnetic resonance imaging scans were reviewed for vascular invasion status.

RESULTS

With median follow-up duration of 40.3 months [95% confidence interval (CI), 36.7-43.8] in surviving patients, median progression-free survival (PFS) and overall survival (OS) were 10.6 (95% CI, 9.5-11.7) and 18.1 (95% CI, 16.0-20.3) months, respectively. The 1-year PFS rate was 66.0% (95% CI, 65.3-66.7%), and the 2-year OS rate was 37.2% (95% CI, 36.5-37.9%). PFS and OS did not differ between BRPC and LAPC groups [median PFS, 11.1 months (95% CI, 8.8-13.5) versus 10.1 months (95% CI, 8.4-11.8), p = 0.47; median OS, 18.4 months (95% CI, 16.1-20.8) versus 17.1 months (95% CI, 13.2-20.9), p = 0.50]. Curative-intent conversion surgery (R0/R1) was performed in 63 patients (31.7%). C•A 19-9 response, objective tumor response to FOLFIRINOX, and conversion surgery were independent prognostic factors for OS.

CONCLUSION

FOLFIRINOX was effective for management of BRPC and LAPC. Given the potential for cure, a significant proportion of patients can undergo conversion curative-intent surgery following FOLFIRINOX.

Arterial resection during pancreatectomy for pancreatic ductal adenocarcinoma with arterial invasion: A single-center experience with 109 patients

Pancreatectomy for pancreatic cancer with arterial invasion is controversial and performed infrequently. As its indication evolves and neoadjuvant chemotherapy also evolves, it is meaningful to identify short- and long-term outcomes of pancreatectomy with arterial resection (AR). This study aimed to retrospectively analyze the clinical outcomes of pancreatectomy with AR for pancreatic ductal adenocarcinoma.Patients with pancreatic ductal adenocarcinoma treated with pancreatectomy with AR at our institute between January 2000 and April 2017 were retrospectively reviewed. Operative outcome and survival were compared according to the presence of neoadjuvant chemotherapy.This study included 109 patients (38 underwent surgery after neoadjuvant chemotherapy, 71 underwent upfront surgery). The median hospital stay was 17 (interquartile range, 12-26.5) days. Clinically relevant postoperative pancreatic fistula (grade B or C) occurred in 14 patients (12.8%). The major morbidity (≥grade III) and mortality rates were 26.6% and 0.9%, respectively. R0 resection was achieved in 80 patients (73.4%). Microscopic actual tumor invasion into the arterial wall was identified in 25 patients (22.9%). The median overall survival (OS) of all patients was 18.4 months. The neoadjuvant chemotherapy group showed better OS than the upfront surgery group, without statistical significance (25.3 vs 16.2 months, P = .06). Progression-free survival was better in patients with neoadjuvant chemotherapy (13.2 vs 7.1 months, P = .01). Patients with partial response to neoadjuvant chemotherapy showed better OS than those with stable disease (33.7 vs 17.5 months, P = .04).Pancreatectomy with AR for advanced pancreatic cancer showed acceptable procedure-related morbidity and mortality. A survival benefit of neoadjuvant chemotherapy was identified, compared to upfront surgery.

A biocomposite-based rapid sampling assay for circulating cell-free DNA in liquid biopsy samples from human cancers

Cell-free nucleic acids (cfNAs) in liquid biopsy samples are emerging as important biomarkers for cancer diagnosis and monitoring, and for predicting treatment outcomes. Many cfNA isolation methods have been developed recently. However, most of these techniques are time-consuming, complex, require large equipment, and yield low-purity cfNAs because the genetic background of normal cells is amplified during cell lysis, which limits their clinical application. Here, we report a rapid and simple cfNA sampling platform that can overcome the limitations of conventional methods. We synthesised a biocomposite by combining amine-modified diatomaceous earth (DE) and cucurbituril (CB). The biocomposite platform showed high capture efficiency (86.78-90.26%) with genomic DNA and amplified DNA products (777, 525 and 150 bp). The biocomposite platform allowed the isolation of high purity and quantity cfDNAs from the plasma of 13 cancer patients (three colorectal cancer and ten pancreatic cancer samples) without requiring a lysis step or special equipment. The biocomposite platform may be useful to isolate cfNAs for the diagnosis and treatment of cancers in clinical applications.

Predictive Factors Associated with Complications after Laparoscopic Distal Pancreatectomy

Although laparoscopic distal pancreatectomy (LDP) has become more popular, the postoperative complication rate remains high. We sought to identify the risk factors for post-LDP complications. We examined 1227 patients who underwent LDP between March 2005 and December 2015 at a single large-volume center. We used logistic regression for the analysis. The overall (13.2%) and major (3.3%) complication rates were determined. Postoperative pancreatic fistula was the most frequent complication, and 58 patients (4.7%) had clinically significant (grade B) pancreatic fistulas. No 90-day mortality was recorded. Long operative time (≥200 min), large estimated blood loss (≥320 mL), LDP performed by an inexperienced surgeon (<50 cases), and concomitant splenectomy were identified as risk factors for overall complications using a logistic regression model. For major complications, male sex (p = 0.020), long operative time (p = 0.005), and LDP performed by an inexperienced surgeon (p = 0.026) were significant predictive factors. Using logistic regression analysis, surgery-related factors, including long operative time and LDP performed by an inexperienced surgeon, were correlated with overall and major complications of LDP. As LDP is a technically challenging procedure, surgery-related variables emerged as the main risk factors for postoperative complications. Appropriate patient selection and sufficient surgeon experience may be essential to reduce the complications of LDP.

CT-determined resectability of borderline resectable and unresectable pancreatic adenocarcinoma following FOLFIRINOX therapy

OBJECTIVES

We aimed to assess the ability of CT-determined resectability, as defined by a recent version of NCCN criteria, and associated CT findings to predict margin-negative (R0) resection in patients with PDAC after neoadjuvant FOLFIRINOX chemotherapy.

METHODS

Sixty-four patients (36 men and 28 women; mean age, 58.8 years) with borderline resectable or unresectable PDAC who received neoadjuvant FOLFIRINOX were evaluated retrospectively. CT findings were independently assessed by two abdominal radiologists according to NCCN criteria (version 3. 2019). Tumor resectability was classified as resectable, borderline resectable, or unresectable, and change in resectability was classified as regression, stability, or progression. The associations of R0 resection rate with CT-determined resectability and change in resectability categories were evaluated, as were the sensitivity and specificity of NCCN criteria for R0 resection. Factors associated with R0 resection were identified by logistic regression analysis.

RESULTS

R0 resection rate did not differ significantly among the resectable, borderline resectable, or unresectable PDAC (67-73%, p = 0.95) or among PDAC with regression, stability, or progression (56-77%, p = 0.39). The sensitivity and specificity for R0 resection were 67% and 37%, respectively, for resectability (resectable/borderline vs. unresectable) and 80% and 21%, respectively, for changes in resectability (regression/stable vs. progression). Low-contrast enhancement of soft tissue contacting artery (≤ 46.4 HU) was independently associated with R0 resection (p = 0.01).

CONCLUSION

CT-determined resectability after neoadjuvant FOLFIRINOX chemotherapy was relatively insensitive and non-specific for predicting R0 resection. Low-contrast enhancement of soft tissue contacting artery may increase the ability of CT to predict R0 resection.

KEY POINTS

• Margin-negative resection rate of pancreatic cancer following FOLFIRINOX therapy did not differ among each resectability (67-73%, p = 0.95) based on NCCN criteria or changes in resectability categories (56-77%, p = 0.39). • The sensitivity and specificity for margin-negative resection were 67% and 37% for resectability (resectable/borderline vs. unresectable) and 80% and 21% for changes in resectability (regression/stable vs. progression). • Low-contrast enhancement of soft tissue contacting artery (≤ 46.4 HU) was independently associated with margin-negative resection (p = 0.01).

Diversity in the Extracellular Vesicle-Derived Microbiome of Tissues According to Tumor Progression in Pancreatic Cancer

This study was conducted to identify the composition and diversity of the microbiome in tissues of pancreatic cancer and to determine its role. First, extracellular vesicles (EVs) were obtained from the paired tumor and normal tissues, and 16s rRNA gene sequencing was performed. We identified the microbiomes, compared the diversity between groups, and found that Tepidimonas was more abundant in tumors. Second, larger tumors resulted in lower levels of Leuconostoc and Sutterella, and increased lymph node metastasis resulted in higher levels of Comamonas and Turicibacter in tumor tissues. Moreover, in the case of tumor recurrence, the levels of Streptococcus and Akkermansia were decreased in tumor tissues. Finally, with the supernatant of Tepidimonasfonticaldi, proliferation and migration of cells increased, and epithelial-mesenchymal transition and the Tricarboxylic Acid (TCA) cycle-related metabolites were enhanced. The composition and diversity of EV-derived microbiomes are important for providing novel insights into theragnostic approaches in pancreatic cancer.

Prognostic implication of high grade biliary intraepithelial neoplasia in bile duct resection margins in patients with resected perihilar cholangiocarcinoma

BACKGROUND

In surgery for perihilar cholangiocarcinoma (PHCC), it is still controversial as to whether additional resection of the bile duct is needed on high grade (HG) biliary intraepithelial neoplasia (BilIN) margin.

METHODS

Patients who underwent surgery for PHCC with curative intent between 2001 and 2015 were stratified by resection margin, and were analyzed comparing the clinical outcomes.

RESULTS

Of the 306 study participants, 217 patients had negative margins (R0), 18 patients had HG BilIN, and 71 patients had positive margins (R1). The median overall survival was 36.0 months in the R0 group, 41.0 months in the HG BilIN group, and 25.0 months in the R1 group while overall survival rates at 5 years were 34.5% in the R0 group, 44.4% in the HG BilIN group, and 21.0% in the R1 group. The median disease-free survival was 15.0 months in the R0 group, 16.5 months in the HG BilIN group, and 12.0 months in the R1 group.

CONCLUSIONS

Although the HG BilIN group had neoplasia with malignant potential, survival and recurrence outcomes were comparable to those of the R0 group, which suggests that no additional resection is needed when the maximal bile duct margin in PHCC surgery contains HG BilIN.

Clinical features and outcomes of endovascular treatment of latent pseudoaneurysmal bleeding after pancreaticoduodenectomy

BACKGROUND

The endovascular treatment is the first-line therapy for late massive arterial haemorrhage after pancreaticoduodenectomy (PD). This study aimed to evaluate the clinical features and outcomes of patients who experienced pseudoaneurysm (PA) bleeding after PD and treated with transcatheter arterial embolization (TAE) and stent-graft placement (SGP).

METHODS

A total of 37 patients (TAE = 16, stent graft = 16, both = 5) had an endovascular treatment due to hepatic artery PA bleeding after PD at our institution from January 2008 to December 2018.

RESULTS

There were 35 men and two women with a mean age of 62 years (range 45-82 years). The latency of bleeding ranged from postoperative days 3 to 46 (median day 21). The most common site of bleeding was gastroduodenal artery stump (n = 22). In TAE group (n = 16), the technical success rate was 100% and the clinical success rate was 87.5%. In SGP group (n = 16), the technical and clinical success rates were 100% and 93.8%. Five patients underwent SGP and TAE simultaneously; TAE was performed to prevent endoleak. A total of three patients experienced hepatic ischaemia (TAE = 2, SGP = 1). However, there was no statistically significant difference of hepatic ischaemia occurrence between the two groups P = 0.55).

CONCLUSIONS

In patients with suspected PA, urgent angiography should be considered immediately for diagnosis and treatment. The SGP can be performed first if it is technically feasible. However, TAE is also a safe and effective treatment in patients with intact portal flow, as well as those with preserved collateral pathways after hepatobiliary surgery.

Obesity susceptible novel DNA methylation marker on regulatory region of inflammation gene: results from the Korea Epigenome Study (KES)

INTRODUCTION

Obesity is growing global health concern and highly associated with increased risk of metabolic diseases including type 2 diabetes. We aimed to discover new differential DNA methylation patterns predisposing obesity and prioritize surrogate epigenetic markers in Koreans.

RESEARCH DESIGN AND METHODS

We performed multistage epigenome-wide analyses to identify differentially expressed CpGs in obesity using the Illumina HumanMethylationEPIC array (EPIC). Forty-eight CpGs showed significant differences across three phases: 902 whole blood DNAs from two cohorts (phase 1: n=450, phase 2: n=377) and a hospital-based sample (phase 3: n=75). Samples from phase III participants were used to examine whether the 48 CpGs are significant in the fat tissue and influenced gene expression. Furthermore, we investigated the epigenetic effect of CpG loci in childhood obesity (n=94).

RESULTS

Seven of the 48 CpGs exhibited similar changes in the fat tissue along with gene expression changes. In particular, hypomethylated CpG (cg13424229) on the GATA1 transcription factor cluster of CPA3 promoter was related to its increased gene expression and showed consistent effect in childhood obesity. Interestingly, subsequent analysis using RNA sequencing data from 21 preadipocytes and 26 adipocytes suggested CPA3 as a potential obesity-related gene. Moreover, expression patterns from RNA sequencing and public Gene Expression Omnibus showed the correlation between CPA3 and type 2 diabetes (T2D) and asthma.

CONCLUSIONS

Our finding prioritizes influential genes in obesity and provides new evidence for the role of CPA3 linking obesity, T2D, and asthma.

Lymph node size and its association with nodal metastasis in ductal adenocarcinoma of the pancreas

Background

Although lymph node metastasis is a poor prognostic factor in patients with pancreatic ductal adenocarcinoma (PDAC), our understanding of lymph node size in association with PDAC is limited. Increased nodal size in preoperative imaging has been used to detect node metastasis. We evaluated whether lymph node size can be used as a surrogate preoperative marker of lymph node metastasis.

Methods

We assessed nodal size and compared it to the nodal metastatic status of 200 patients with surgically resected PDAC. The size of all lymph nodes and metastatic nodal foci were measured along the long and short axis, and the relationships between nodal size and metastatic status were compared at six cutoff points.

Results

A total of 4,525 lymph nodes were examined, 9.1% of which were metastatic. The mean size of the metastatic nodes (long axis, 6.9±5.0 mm; short axis, 4.3±3.1 mm) was significantly larger than that of the non-metastatic nodes (long axis, 5.0±4.0 mm; short axis, 3.0±2.0 mm; all p<.001). Using a 10 mm cutoff, the sensitivity, specificity, positive predictive value, overall accuracy, and area under curve was 24.8%, 88.0%, 17.1%, 82.3%, and 0.60 for the long axis and 7.0%, 99.0%, 40.3%, 90.6%, and 0.61 for the short axis, respectively.

Conclusions

The metastatic nodes are larger than the non-metastatic nodes in PDAC patients. However, the difference in nodal size was too small to be identified with preoperative imaging. The performance of preoperative radiologic imaging to predict lymph nodal metastasis was not good. Therefore, nodal size cannot be used a surrogate preoperative marker of lymph node metastasis.

The identification of candidate effective combination regimens for pancreatic cancer using the histoculture drug response assay

The prognosis for patients with pancreatic cancer is extremely poor, as they are resistant to first line chemotherapy. The long-term goal of this study was to identify effective combination chemotherapy for pancreatic cancer using pancreatic cancer surgical specimens in the histoculture drug response assay (HDRA) based on three-dimensional culture of tumour fragments, which maintains nature tumour histology in vitro. From 2015 to 2017, the HDRA was performed with tumour specimens from 52 pancreatic cancer patients from Asan Medical Hospital. First, combination drug regimens showed higher drug efficacy and less patient variation than single drugs. Initially, 5-Fluorouracil(5-FU)/Belotecan/Oxaliplatinum and Tegafur/Gimeracil (TS-1)/Oxaliplatinum/Irinotecan were found to be effective. Second, we were able to correlate the efficacy of some drugs with tumour stage. Third, when designing new combination regimens containing 5-FU or gemcitabine, we could identify more effective drug combinations. This is the first study to demonstrate usefulness of the HDRA for pancreatic cancer. Using this technique, we could identify novel candidate combination drug regimens that should be effective in treating pancreatic cancer.

Integrated Analysis of Tissue-Specific Promoter Methylation and Gene Expression Profile in Complex Diseases

This study investigated whether the promoter region of DNA methylation positively or negatively regulates tissue-specific genes (TSGs) and if it correlates with disease pathophysiology. We assessed tissue specificity metrics in five human tissues, using sequencing-based approaches, including 52 whole genome bisulfite sequencing (WGBS), 52 RNA-seq, and 144 chromatin immunoprecipitation sequencing (ChIP-seq) data. A correlation analysis was performed between the gene expression and DNA methylation levels of the TSG promoter region. The TSG enrichment analyses were conducted in the gene-disease association network (DisGeNET). The epigenomic association analyses of CpGs in enriched TSG promoters were performed using 1986 Infinium MethylationEPIC array data. A correlation analysis showed significant associations between the promoter methylation and 449 TSGs' expression. A disease enrichment analysis showed that diabetes- and obesity-related diseases were high-ranked. In an epigenomic association analysis based on obesity, 62 CpGs showed statistical significance. Among them, three obesity-related CpGs were newly identified and replicated with statistical significance in independent data. In particular, a CpG (cg17075888 of PDK4), considered as potential therapeutic targets, were associated with complex diseases, including obesity and type 2 diabetes. The methylation changes in a substantial number of the TSG promoters showed a significant association with metabolic diseases. Collectively, our findings provided strong evidence of the relationship between tissue-specific patterns of epigenetic changes and metabolic diseases.

Rationally designed redirection of natural killer cells anchoring a cytotoxic ligand for pancreatic cancer treatment

The emergence of T-cell engineering with chimeric antigen receptors (CARs) has led to attractive therapeutics; however, autologous CAR-T cells are associated with poor clinical outcomes in solid tumors because of low safety and efficacy. Therefore, the aim of our study was to develop a CAR therapy with enhanced cytotoxicity against solid cancer using allogeneic NK cells. In this study, we engineered "off-the-shelf" NK cells to redirect them towards pancreatic ductal adenocarcinoma (PDAC) by improving their target-specific cytotoxic potential. By integrated bioinformatic and clinicopathological analyses, folate receptor alpha (FRα) and death receptor 4 (DR4) were significantly highly expressed in patient-derived tumor cells. The combined expression of FRα and DR4/5 was associated with inferior clinical outcomes, therefore indicating their use as potential targets for biomolecular treatment. Thus, FRα and DR4 expression pattern can be a strong prognostic factor as promising therapeutic targets for the treatment of PDAC. For effective PDAC treatment, allogeneic CAR-NK cells were reprogrammed to carry an apoptosis-inducing ligand and to redirect them towards FRα and initiate DR4/5-mediated cancer-selective cell death in FRα- and DR4/5-positive tumors. As a result, the redirected cytotoxic ligand-loaded NK cells led to a significantly enhanced tumor-selective apoptosis. Accordingly, use of allogeneic CAR-NK cells that respond to FRα and DR4/5 double-positive cancers might improve clinical outcomes based on personal genome profiles. Thus, therapeutic modalities based on allogeneic NK cells can potentially be used to treat large numbers of patients with optimally selective cytotoxicity.

Estimating Recurrence after Upfront Surgery in Patients with Resectable Pancreatic Ductal Adenocarcinoma by Using Pancreatic CT: Development and Validation of a Risk Score

Background No preoperative model is available for predicting postsurgical prognosis of patients with resectable pancreatic ductal adenocarcinoma (PDAC). Purpose To develop and validate a preoperative risk scoring system using clinical and CT variables to predict recurrence-free survival (RFS) after upfront surgery in patients with resectable PDAC. Materials and Methods In this retrospective study, consecutive patients with resectable PDAC underwent upfront surgery from January 2014 to December 2015 (development set) and from January 2016 to January 2017 (test set). In the development set, multivariable Cox proportional hazard modeling with bootstrapping was used to select clinical and CT variables associated with RFS and to construct a risk scoring system. The discrimination capability of the risk score was assessed by using the Harrell C-index and compared with that of pathologic American Joint Committee on Cancer tumor stage. The risk score was validated in the test set. Results A total of 395 patients were evaluated, including 262 patients (mean age ± standard deviation, 64 years ± 10; 155 men) in the development set and 133 (mean age, 64 years ± 9; 79 men) in the test set. Five independent variables predicted risk of recurrence or death: tumor size (hazard ratio [HR], 1.23; 95% confidence interval [CI]: 1.05, 1.44; P = .009), hypodense tumor in the portal venous phase (HR, 1.66; 95% CI: 1.01, 2.73; P = .04), tumor necrosis (HR, 2.04; 95% CI: 1.38, 3.03; P < .001), peripancreatic tumor infiltration (HR, 1.50; 95% CI: 1.07, 2.11; P = .02), and suspicious metastatic lymph nodes (HR, 1.94; 95% CI: 1.38, 2.72; P < .001). In the test set, the risk score showed good discrimination capability (C-index of 0.68; 95% CI: 0.63, 0.74) and outperformed the pathologic tumor stage (C-index of 0.60; 95% CI: 0.55, 0.66; P = .03). Patients were categorized into favorable, intermediate, and poor prognosis groups with 1-year RFS of 0.87, 0.58, and 0.26, respectively. Conclusion The presented preoperative risk score can predict recurrence-free survival after upfront surgery in patients with resectable pancreatic ductal adenocarcinoma. © RSNA, 2020 Online supplemental material is available for this article. See also the editorial by Pandharipande and Anderson in this issue.

A Comparative Study of Laparoscopic versus Open Pancreaticoduodenectomy for Ampulla of Vater Carcinoma

Several studies have compared laparoscopic pancreaticoduodenectomy (LPD) and open pancreaticoduodenectomy (OPD) in patients with periampullary carcinoma; however, only a few studies have made such a comparison on patients with ampulla of Vater cancer (AVC). We compared the perioperative and oncologic outcomes between LPD and OPD in patients with AVC using propensity-score-matched analysis. A total of 359 patients underwent PD due to AVC during the study period (76 LPD, 283 OPD). After propensity score matching, the LPD group showed significantly longer operation time than did the OPD group (400.2 vs. 344.6 min, p < 0.001). Nevertheless, the LPD group had fewer painkiller administrations (8.3 vs. 11.1, p < 0.049), fewer Grade II or more severe postoperative complications (15.9% vs. 34.8%, p = 0.012), and shorter postoperative hospital stays (13.7 vs. 17.3 days, p = 0.048), compared with the OPD group. There was no significant difference in recurrence-free outcomes and overall survival between the two groups (p = 0.754 and 0.768, respectively). Compared with OPD, LPD for AVC had comparative oncologic outcomes with less pain, less postoperative morbidity, and shorter hospital stays. LPD may serve as a promising alternative to OPD in patients with AVC.

Propensity score-matched analysis of internal stent vs external stent for pancreatojejunostomy during pancreaticoduodenectomy: Japanese-Korean cooperative project

BACKGROUND

Several studies comparing internal and external stents have been conducted with the aim of reducing pancreatic fistula after PD. There is still no consensus, however, on the appropriate use of pancreatic stents for prevention of pancreatic fistula. This multicenter large cohort study aims to evaluate whether internal or external pancreatic stents are more effective in reduction of clinically relevant pancreatic fistula after pancreaticoduodenectomy (PD).

METHODS

We reviewed 3149 patients (internal stent n = 1,311, external stent n = 1838) who underwent PD at 20 institutions in Japan and Korea between 2007 and 2013. Propensity score matched analysis was used to minimize bias from nonrandomized treatment assignment. The primary endpoint was the incidence of clinically relevant pancreatic fistula. This study was registered on the UMIN Clinical Trials Registry (UMIN000032402).

RESULTS

After propensity score matched analysis, clinically relevant pancreatic fistula occurred in more patients in the external stents group (280 patients, 28.7%) than in patients in the internal stents group (126 patients, 12.9%) (OR 2.713 [95% CI, 2.139-3.455]; P < 0.001). In subset analysis of a high-risk group with soft pancreas and no dilatation of the pancreatic duct, clinically relevant pancreatic fistula occurred in 90 patients (18.8%) in internal stents group and 183 patients (35.4%) in external stents group. External stents were significantly associated with increased risk for clinically relevant pancreatic fistula (OR 2.366 [95% CI, 1.753-3.209]; P < 0.001).

CONCLUSION

Propensity score matched analysis showed that, regarding clinically relevant pancreatic fistula after PD, internal stents are safer than external stents for pancreaticojejunostomy.

Association between Metformin Use and Clinical Outcomes Following Pancreaticoduodenectomy in Patients with Type 2 Diabetes and Pancreatic Ductal Adenocarcinoma

Retrospective studies on the association between metformin and clinical outcomes have mainly been performed on patients with non-resectable pancreatic ductal adenocarcinoma and may have been affected by time-related bias. To avoid this bias, recent studies have used time-varying analysis; however, they have only considered the start date of metformin use and not the stop date. We studied 283 patients with type 2 diabetes and pancreatic ductal adenocarcinoma following pancreaticoduodenectomy, and performed analysis using a Cox model with time-varying covariates, while considering both start and stop dates of metformin use. When start and stop dates were not considered, the metformin group showed significantly better survival. Compared with previous studies, adjusted analysis based on Cox models with time-varying covariates only considering the start date of postoperative metformin use showed no significant differences in survival. However, although adjusted analysis considering both start and stop dates showed no significant difference in recurrence-free survival, the overall survival was significantly better in the metformin group (Hazard ratio (HR), 0.747; 95% confidence interval (CI), 0.562–0.993; p = 0.045). Time-varying analysis incorporating both start and stop dates thus revealed that metformin use is associated with a higher overall survival following pancreaticoduodenectomy in patients with type 2 diabetes and pancreatic ductal adenocarcinoma.

Long-term reversal of diabetes by subcutaneous transplantation of pancreatic islet cells and adipose-derived stem cell sheet using surface-immobilized heparin and engineered collagen scaffold

OBJECTIVE

Esterified collagen (EC) can be functionalized with heparin to enhance islet graft stability. Growth factors secreted by human adipose-derived stem cells (hADSCs) can bind efficiently to EC-heparin (EC-Hep), which enhances revascularization and cell protection. We investigated the therapeutic potential of a combined heparin-esterified collagen-hADSC (HCA)-islet sheet to enhance islet engraftment.

RESEARCH DESIGN AND METHODS

This study was designed to assess the efficiency of using EC-Hep as a scaffold for subcutaneous islet transplantation in diabetic athymic mice. After the hADSC-cocultured islets were seeded in the EC-Hep scaffold, islet function was measured by glucose-stimulated insulin secretion test and growth factors in the culture supernatants were detected by protein array. Islet transplantation was performed in mice, and graft function and survival were monitored by measuring the blood glucose levels. β-Cell mass and vascular densities were assessed by immunohistochemistry.

RESULTS

The EC-Hep composite allowed sustained release of growth factors. Secretion of growth factors and islet functionality in the HCA-islet sheet were significantly increased compared with the control groups of islets alone or combined with native collagen. In vivo, stable long-term glucose control by the graft was achieved after subcutaneous transplantation of HCA-islet sheet due to enhanced capillary network formation around the sheet.

CONCLUSIONS

The findings indicate the potential of the HCA-islet sheet to enhance islet revascularization and engraftment in a hADSC dose-dependent manner, following clinical islet transplantation for the treatment of diabetes mellitus.