A Circulating Panel of circRNA Biomarkers for the Noninvasive and Early Detection of Pancreatic Ductal Adenocarcinoma.

BACKGROUND & AIMS: Pancreatic ductal adenocarcinoma (PDAC) is one of the most fatal malignancies. Delayed manifestation of symptoms and lack of specific diagnostic markers lead patients being diagnosed with PDAC at advanced stages. This study aimed to develop a circular RNA (circRNA)-based biomarker panel to facilitate noninvasive and early detection of PDAC. METHODS: A systematic genome-wide discovery of circRNAs overexpressed in patients with PDAC was conducted. Subsequently, validation of the candidate markers in the primary tumors from patients with PDAC was performed, followed by their translation into a plasma-based liquid biopsy assay by analyzing 2 independent clinical cohorts of patients with PDAC and nondisease controls. The performance of the circRNA panel was assessed in conjunction with the plasma levels of cancer antigen 19-9 for the early detection of PDAC. RESULTS: Initially, a panel of 10 circRNA candidates was identified during the discovery phase. Subsequently, the panel was reduced to 5 circRNAs in the liquid biopsy-based assay, which robustly identified patients with PDAC and distinguished between early-stage (stage I/II) and late-stage (stage III/IV) disease. The areas under the curve of this diagnostic panel for the detection of early-stage PDAC were 0.83 and 0.81 in the training and validation cohorts, respectively. Moreover, when this panel was combined with cancer antigen 19-9 levels, the diagnostic performance for identifying patients with PDAC improved remarkably (area under the curve, 0.94) for patients in the validation cohort. Furthermore, the circRNA panel could also efficiently identify patients with PDAC (area under the curve, 0.85) who were otherwise deemed clinically cancer antigen 19-9-negative (<37 U/mL). CONCLUSIONS: A circRNA-based biomarker panel with a robust noninvasive diagnostic potential for identifying patients with early-stage PDAC was developed.

High-throughput drug screening using a library of antibiotics targeting cancer cell lines that are resistant and sensitive to gemcitabine.

Gemcitabine is a nucleoside analog widely used as an anticancer agent against several types of cancer. Although gemcitabine sometimes shows excellent effectiveness, cancer cells are often poorly responsive to or resistant to the drug. Recently, specific strains or dysbiosis of the human microbiome were correlated with drug reactivity and resistance acquisition. Therefore, we aimed to identify antibiotic compounds that can modulate the microbiome to enhance the responsiveness to gemcitabine. To achieve this, we confirmed the gemcitabine responsiveness based on public data and conducted drug screening on a set of 250 antibiotics compounds. Subsequently, we performed experiments to investigate whether the selected compounds could enhance the responsiveness to gemcitabine. First, we grouped a total of seven tumor cell lines into resistant and sensitive group based on the IC50 value (1 µM) of gemcitabine obtained from the public data. Second, we performed high-throughput screening with compound treatments, identifying seven compounds from the resistant group and five from the sensitive group based on dose dependency. Finally, the combination of the selected compound, puromycin dihydrochloride, with gemcitabine in gemcitabine-resistant cell lines resulted in extensive cell death and a significant increase in cytotoxic efficacy. Additionally, mRNA levels associated with cell viability and stemness were reduced. Through this study, we screened antibiotics to further improve the efficacy of existing anticancer drugs and overcome resistance. By combining existing anticancer agents and antibiotic substances, we hope to establish various drug combination therapies and ultimately improve cancer treatment efficacy.

Characterization of lymphocyte-rich hepatocellular carcinoma and the prognostic role of tertiary lymphoid structures.

BACKGROUND & AIMS: Lymphocyte-rich hepatocellular carcinoma (LR-HCC) is largely unknown and a rare subtype of HCC with immune-rich stroma. Tertiary lymphoid structures (TLS), frequently observed in LR-HCC, are known to be prognostically significant in various malignancies; however, their significance in HCC remains unevaluated. METHODS: Clinicopathologic data of 191 cases of surgically resected conventional HCC (C-HCC, n = 160) and LR-HCC (n = 31) were retrieved. Immunohistochemistry, multiplex immunofluorescence staining, RNA sequencing and proteomic analysis were conducted. Differences between the subtypes were statistically evaluated. RESULTS: LR-HCC was significantly correlated to larger tumour size, higher Edmondson-Steiner grade, presence of TLS and higher CD3-, CD8- and FOXP3-positive T cell, high PD-1 and PD-L1 expression (p < .001 for all) compared to C-HCC. Patients with LR-HCC exhibited significantly better overall survival (OS) (p = .044) and recurrence-free survival (RFS) (p = .025) than C-HCC. LR-HCC demonstrated TLS signatures with significantly higher proteomic-based immune scores in 14 of 17 types of tumour-infiltrating immune cells. Furthermore, C-HCC with secondary follicles, the most mature form of TLS, exhibited significantly better OS (p = .031) and RFS (p = .033) than those without. Across the global proteome, LR-HCC was well-differentiated from C-HCC and a map of protein-protein interactions between tumour-infiltrating lymphocytes and HCC in tumour microenvironment was completed. CONCLUSION: LR-HCC is clinicopathologically and molecularly distinct and shows better prognosis compared to C-HCC. Also, the presence of secondary follicle can be an important prognostic marker for better prognosis in both LR-HCC and C-HCC.

An Exosome-based Transcriptomic Signature for Noninvasive, Early Detection of Patients With Pancreatic Ductal Adenocarcinoma: A Multicenter Cohort Study.

BACKGROUND & AIMS: Pancreatic ductal adenocarcinoma (PDAC) incidence is rising worldwide, and most patients present with an unresectable disease at initial diagnosis. Measurement of carbohydrate antigen 19-9 (CA19-9) levels lacks adequate sensitivity and specificity for early detection; hence, there is an unmet need to develop alternate molecular diagnostic biomarkers for PDAC. Emerging evidence suggests that tumor-derived exosomal cargo, particularly micro RNAs (miRNAs), offer an attractive platform for the development of cancer-specific biomarkers. Herein, genomewide profiling in blood specimens was performed to develop an exosome-based transcriptomic signature for noninvasive and early detection of PDAC. METHODS: Small RNA sequencing was undertaken in a cohort of 44 patients with an early-stage PDAC and 57 nondisease controls. Using machine-learning algorithms, a panel of cell-free (cf) and exosomal (exo) miRNAs were prioritized that discriminated patients with PDAC from control subjects. Subsequently, the performance of the biomarkers was trained and validated in independent cohorts (n = 191) using quantitative reverse transcription polymerase chain reaction (qRT-PCR) assays. RESULTS: The sequencing analysis initially identified a panel of 30 overexpressed miRNAs in PDAC. Subsequently using qRT-PCR assays, the panel was reduced to 13 markers (5 cf- and 8 exo-miRNAs), which successfully identified patients with all stages of PDAC (area under the curve [AUC] = 0.98 training cohort; AUC = 0.93 validation cohort); but more importantly, was equally robust for the identification of early-stage PDAC (stages I and II; AUC = 0.93). Furthermore, this transcriptomic signature successfully identified CA19-9 negative cases (<37 U/mL; AUC = 0.96), when analyzed in combination with CA19-9 levels, significantly improved the overall diagnostic accuracy (AUC = 0.99 vs AUC = 0.86 for CA19-9 alone). CONCLUSIONS: In this study, an exosome-based liquid biopsy signature for the noninvasive and robust detection of patients with PDAC was developed.

Minimally invasive versus open pancreaticoduodenectomy for distal bile duct cancer: an inverse probability of treatment weighting analysis of outcomes.

BACKGROUND: Minimally invasive pancreaticoduodenectomy (MIPD) has been extended to periampullary cancers, but the oncologic outcome of MIPD for distal bile duct cancer (DBDC) has not been confirmed yet. METHODS: Patients who underwent pancreaticoduodenectomy (PD) for DBDC of stage I-IIb from 2015 to 2019 at a tertiary referral center were identified and divided into open PD (OPD) and MIPD groups, the latter including laparoscopic and robotic procedures. Survival was compared between the two groups after inverse probability of treatment weighting (IPTW) using predetermined factors, and exploratory mediation analysis was performed using surgery-derived outcomes. RESULTS: MIPD (n = 81) group had more female patients (46.9% vs 31.6%, p = 0.011) and longer operation time (366.2 min vs. 279.1 min, p < 0.001) than the OPD (n = 288) group before IPTW. Otherwise, intraoperative and immediate postoperative outcomes were comparable between the two groups. In oncologic outcomes, MIPD group showed comparable 3-year overall survival (78.2% vs 75.0%, p = 0.062) and recurrence-free survival (51.2% vs 53.4%, p = 0.871) rates with OPD group before IPTW, and MIPD was not related with survival (hazard ratio [HR] 0.61, 95% confidence interval [CI] 0.29-1.26, p = 0.18) and recurrence (HR 1.01, 95% CI 0.67-1.53, p = 0.949) after IPTW with consideration of potential mediators. Sensitivity analysis using propensity score matching also showed similar results for survival (HR 0.68, 95% CI 0.32-1.44, p = 0.312) and recurrence (HR 1.12, 95% CI 0.67-1.88, p = 0.653). CONCLUSION: MIPD and OPD groups showed similar postoperative and oncologic outcomes. MIPD could be a considerable treatment option without oncological compromise in high-volume centers.

Transcriptomic Profiling Identifies an Exosomal microRNA Signature for Predicting Recurrence Following Surgery in Patients With Pancreatic Ductal Adenocarcinoma.

OBJECTIVE: We performed genome-wide expression profiling to develop an exosomal miRNA panel for predicting recurrence following surgery in patients with PDAC. SUMMARY OF BACKGROUND DATA: Pretreatment risk stratification is essential for offering individualized treatments to patients with PDAC, but predicting recurrence following surgery remains clinically challenging. METHODS: We analyzed 210 plasma and serum specimens from 4 cohorts of PDAC patients. Using a discovery cohort (n = 25), we performed genome-wide sequencing to identify candidate exosomal miRNAs (exo-miRNAs). Subsequently, we trained and validated the predictive performance of the exo-miRNAs in two clinical cohorts (training cohort: n = 82, validation cohort: n = 57) without neoadjuvant therapy (NAT), followed by a post-NAT clinical cohort (n = 46) as additional validation. RESULTS: We performed exo-miRNA expression profiling in plasma specimens obtained before any treatment in a discovery cohort. Subsequently we optimized and trained a 6-exo-miRNA risk-prediction model, which robustly discriminated patients with recurrence [area under the curve (AUC): 0.81, 95% confidence interval (CI): 0.70-0.89] and relapse-free survival (RFS, P < 0.01) in the training cohort. The identified exo-miRNA panel was successfully validated in an independent validation cohort (AUC: 0.78, 95% CI: 0.65- 0.88, RFS: P < 0.01), where it exhibited comparable performance in the post-NAT cohort (AUC: 0.72, 95% CI: 0.57-0.85, RFS: P < 0.01) and emerged as an independent predictor for RFS (hazard ratio: 2.84, 95% CI: 1.30-6.20). CONCLUSIONS: We identified a novel, noninvasive exo-miRNA signature that robustly predicts recurrence following surgery in patients with PDAC; highlighting its potential clinical impact for optimized patient selection and improved individualized treatment strategies.

Predictive Performance of Current Nodal Staging Systems in Various Categories of Pancreatic Cancer.

BACKGROUND: Nodal staging systems (NSS) for pancreatic ductal adenocarcinoma (PDAC) classify patients on the basis of number of metastatic lymph nodes (MLN), metastatic/retrieved lymph node ratio (LNR), and log odds of positive LN (LODDS). The relative prognostic performance of these NSS, however, remains unclear. PATIENTS AND METHODS: We identified 2584 patients who underwent surgery for PDAC between 2010 and 2019. Subgroups of each staging system were classified using K-adaptive partitioning method and assessed by comparing time-dependent areas under the curve (AUC) 5 years after surgery. RESULTS: Patients were subgrouped by MLN (0, 1-3, ≥ 4), LNR (0, 0-0.23, > 0.23), and LODDS (< - 3.5, - 3.5 to - 0.970, > - 0.97). All three NSS were independent prognostic factors for overall survival (OS) and recurrence-free survival (RFS). The AUCs for OS were comparable for the MLN (0.622), LNR (0.609), and LODDS (0.596) systems. Subgroup evaluation based on 12 retrieved lymph nodes (RLN), R1 resection, and extent of resection showed that the AUCs of the MLN and LNR NSS were comparable for OS and RFS regardless of the number of RLNs, R1 resection, and extent of resection. By contrast, the AUCs of the LODDS NSS were lower. CONCLUSION: The NSS based on the number of MLN is the best prognostic indicator, with prognostic performance comparable to the other NSS and greater convenience for practical use. This NSS was applicable regardless of the numbers of RLN, R1 resection, and extent of resection.

Controversial benefit of 5-fluorouracil/leucovorin-based adjuvant chemotherapy for ampullary cancer: a propensity score-matched analysis.

BACKGROUND: Although surgery is the primary treatment for ampullary cancer (AC), the benefit of adjuvant chemotherapy (CTx) has not yet been confirmed. METHODS: AC patients who were administered 5-fluorouracil(FU)/leucovorin(LV)-based CTx after curative intent surgery between 2011 and 2019 were included. Prognosis was compared between the observation (OB) and CTx groups after propensity score matching (PSM) using perioperative variables to control differences in patient characteristics. RESULTS: Before PSM, of 475 patients, those in the CTx group (n = 281) had worse 5-year overall survival (OS) (82.1% vs. 78.5%, p = 0.017) and worse 5-year recurrence-free survival (RFS) (54.9% vs. 75.7%, p < 0.001) than those in the OB group (n = 194). In addition, the CTx group had a higher rate of poor prognostic factors such as a high T stage (p < 0.001), node metastasis (p < 0.001), and poor differentiation (p < 0.001). After PSM, perioperative outcomes were comparable. In addition, there were no significant differences in OS (hazard ratio [HR], 1.085; 95% confidence interval [CI], 0.688-1.710; p = 0.726) or RFS (HR, 0.883; 95% CI, 0.613 1.272; p = 0.505) between the CTx (n = 123) and OB (n = 123) groups even after stratification by TNM stage. Intestinal subtype showed better 5-year OS (83.7% vs 33.2%, p = 0.015) and RFS (46.5% vs 24.9%, p = 0.035) rate compared with pancreatobiliary/mixed subtype. CONCLUSION: Patients who received adjuvant chemotherapy based on 5-FU/LV showed comparable oncologic outcomes to patients in the OB group even after stratification by tumor stage. The patients with intestinal subtype showed oncologic benefit for adjuvant 5-FU/LV CTx compared with pancreatobiliary or mixed subtypes.

Metabolic activity by FDG-PET/CT after neoadjuvant chemotherapy in borderline resectable and locally advanced pancreatic cancer and association with survival.

BACKGROUND: The optimal prognostic markers for neoadjuvant chemotherapy in patients with borderline resectable or locally advanced pancreatic cancer are not yet established. METHOD: Patients who received neoadjuvant chemotherapy prior to surgery and underwent FDG-PET/CT between July 2012 and December 2017 were included. Metabolic parameters including standardized uptake value (SUV), metabolic tumour volume (MTV), and total lesion glycolysis (TLG) on PET/CT, and response evaluations using PERCIST criteria, were investigated for its impact on survival and recurrence. Cox proportional hazards model was performed. Differences in risk were expressed as hazard ratio (HR) with 95 per cent confidence interval. RESULTS: The patients with borderline resectable (N = 106) or locally advanced pancreatic cancer (N = 82) were identified. The median survival was 33.6 months. Decreased metabolic parameters of PET/CT after neoadjuvant chemotherapy were associated with positive impacts on survival and recurrence such as SUVmax (HR 1.16, 95 per cent c.i. 1.01 to 1.32, P = 0.025), SUVpeak (HR 1.26, 95 per cent c.i. 1.05 to 1.51, P = 0.011), and MTV (HR 1.15, 95 per cent c.i. 1.04 to 1.26, P = 0.005). Large delta values were related to a positive impact on recurrence such as SUVmax (HR 1.21, 95 per cent c.i. 1.06 to 1.38, P = 0.005). Post-neoadjuvant chemotherapy SUVmax ≥3 (HR 3.46, 95 per cent c.i. 1.21 to 9.91; P = 0.036) was an independent prognostic factor for negative impact on survival. Patients with post-neoadjuvant chemotherapy SUVmax <3 showed more chemotherapy cycles (8.7 versus 6.2, P = 0.001), more frequent complete metabolic response (25 versus 2.2 per cent, P = 0.002), smaller tumour size (2.1 versus 3.1 cm, P = 0.002), and less frequent lymphovascular invasion (23.7 versus 51.1 per cent, P = 0.020) than patients with SUVmax ≥3. CONCLUSION: Reduction in metabolic tumour parameters of FDG- PET/CT after neoadjuvant chemotherapy indicates improved overall survival and recurrence-free survival.

Enhanced insulin production and reprogramming efficiency of mesenchymal stem cells derived from porcine pancreas using suitable induction medium.

BACKGROUND: Genetic reprogramming is a powerful method for altering cell properties and inducing differentiation. However, even if the same gene is reprogrammed, the results vary among cells. Therefore, a better possible strategy involves treating cells with factors that further stimulate differentiation while using stem cells with the same tissue origin. This study aimed to increase induction efficiency and insulin production in reprogrammed cells using a combination of factors that promote cell differentiation. METHODS: Porcine pancreatic cells were cultured to obtain mesenchymal stem cells expressing pancreatic cell-specific markers through sequential passages. The characteristics of these cells were identified, and the M3 gene (Pdx1, Ngn3, MafA) was reprogrammed to induce differentiation into insulin-producing cells. Additionally, the differentiation efficiency of insulin-producing cells was compared by treating reprogrammed cells with a differentiation-promoting factor. RESULTS: Mesenchymal stem cells isolated from porcine pancreatic tissues expressed exocrine cell markers, including amylase and cytokeratin 18, and most cells continuously expressed the beta cell transcription factors Ngn3 and NeuroD. Reprogramming of the M3 gene resulted in differentiation into insulin-producing cells. Moreover, significantly increased insulin and glucagon expressions were observed in the suitable induction medium, and the characteristic beta cell transcription factors Pdx1, Ngn3, and MafA were expressed at levels as high as those in pancreatic islet cells. CONCLUSIONS: Differentiation into insulin-producing cells represents an alternative therapy for insufficient pancreatic islet cells when treating diabetes. Therefore, cells with the characteristics of the target cell should be used to improve differentiation efficiency by creating an environment that promotes reprogramming and differentiation.

Totally laparoscopic or robot-assisted pancreaticoduodenectomy versus open surgery for periampullary neoplasms: separate systematic reviews and meta-analyses.

OBJECTIVE: To compare perioperative and oncologic outcomes of pure (totally) laparoscopic pancreaticoduodenectomy (TLPD) or robot-assisted pancreaticoduodenectomy (RAPD) with those of conventional open pancreaticoduodenectomy (OPD). METHODS: A systematic literature search was performed using PubMed, EMBASE, and Cochrane library databases. Studies comparing TLPD with OPD and RAPD with OPD were included; only original studies reporting more than 10 cases for each technique were included. Studies were combined using a random-effects model to report heterogeneous data, or a fixed-effects model was applied. RESULTS: TLPD involved longer operative time (weighted mean difference [WMD]: 116.85 min; 95% confidence interval [CI] 54.53-179.17) and significantly shorter postoperative hospital stay (WMD: -3.68 days; 95% CI -4.65 to -2.71). Overall morbidity and postoperative pancreatic fistula were not significantly different between TLPD and OPD. RAPD was associated with a longer operative time, less intraoperative blood loss, and shorter hospital stay. Oncologic outcomes were not significantly different among the procedure types. CONCLUSIONS: Compared to OPD, TLPD and RAPD were feasible and oncologically safe procedures. However, there are no prospective studies, and the majority of the studies on TLPD and RAPD have remained in the early training phase. In addition to randomized controlled trials or prospective studies, new data from the late training phase of learning experiences should also be analyzed.

Designing Peptide Bunches on Nanocage for Bispecific or Superaffinity Targeting.

Ferritin cage nanoparticles are promising platforms for targeted delivery of imaging and therapeutic agents because their cage structure can accommodate small molecules and their surfaces can be decorated with multiple functionalities. However, selective targeting is still a challenge for translating ferritin-based nanomedicines into the clinic, especially for heterogeneous diseases such as cancer. Targeting peptides can be genetically fused onto the surface of a ferritin cage, forming peptide bunches on nanocages (PBNCs) that offer synergistic increases in binding avidity. Here, we utilized two sites of the ferritin monomer, the N-terminus and the loop between the fourth and fifth helices, which are exposed on the surface of the assembled 24-subunit ferritin cage, to ligate one or two types of peptides to achieve "super affinity" and bispecificity, respectively. PBNCs formed by ligation of the IL-4 receptor-targeting peptide, AP1, to both sites (48AP1-PBNCs) tethered IL-4R, expressing tumor cells with greater affinity than did PBNCs with AP1 ligated to a single site (24AP1-PBNCs). Moreover, bispecific PBNCs containing 24 RGD peptides and 24 AP1 peptides (24RGD/24AP1-PBNCs) were capable of independently targeting cells expressing the corresponding receptors. Bispecific and superaffinity PBNCs could be useful for efficient targeting of ferritin-based therapeutic/diagnostic agents in a clinical setting.

Proposed diagnostic and prognostic markers of primary malignant hepatic vascular neoplasms.

INTRODUCTION: Primary malignant hepatic vascular tumors with various malignant potentials include epithelioid hemangioendothelioma (EHE) and angiosarcoma (AS), which may overlap pathologically. This study aimed to compare the pathological findings of hepatic EHE with those of AS, in association with patient outcomes. METHODS: Fifty-nine histologically confirmed patients with 34 EHE and 25 AS were admitted to a tertiary hospital from 2003 to 2020. Their EHE and AS pathological features were compared. Immunohistochemistry for CD31, ERG, CAMTA-1, TFE3, P53, and Ki-67 labeling was performed on paraffin-embedded blocks. Markers, along with histological findings, were analyzed for the purposes of diagnostic and prognostic significance by multivariate analysis. RESULTS: CAMTA-1 was 91.2% positive in EHE, but negative in AS (p = < 0.001). AS was significantly correlated to an aberrant p53 expression, high Ki-67 labeling, and high mitotic activity, compared to EHE (all, p = < 0.001). EHE can be classified as low grade (LG) and high grade (HG) using the prognostic values of mitotic activity and ki-67 labeling (sensitivity = 1, specificity = 1). Low grade-EHE showed significantly better overall survival than high grade-EHE (p = 0.020). CONCLUSIONS: Immunohistochemistry for CAMTA-1, P53, and Ki-67 labeling may help distinguish EHE and AS in histologically ambiguous cases, especially small biopsied tissue. Moreover, the combination of mitotic activity and Ki-67 labeling can be a prognostic factor for EHE with various clinical features.

Clinical implication of the geometric location (fundal end versus cystic ductal end) of gallbladder cancer.

BACKGROUND: Management of early-stage gallbladder cancer is becoming more important as the rate of early detection is increasing. Although there have been many studies about the clinical implication of the invasion depth or peritoneal/hepatic location of gallbladder cancers, there is no study on the clinical implication of the geometric location of cancer along the longitudinal length of the gallbladder. METHODS: The location of gallbladder cancer was defined as the geometric center of the primary site of a tumour, which lies on the longitudinal diameter of the surgical specimens. We compared the oncologic outcomes following surgery between gallbladder cancers located on the fundal end and those located on the cystic ductal end. We also analysed patients with stage 1 gallbladder cancer who recurred after surgery. RESULTS: A total of 575 patients with gallbladder cancer were included in this study. Patients with gallbladder cancer on the cystic ductal end had significantly lower rates of recurrence-free survival (P = 0.016) and overall survival (P = 0.023) compared to those with gallbladder cancer on the fundal end. Among 90 patients with stage 1 gallbladder cancer, three patients had a recurrence, all of whom had cystic ductal end gallbladder cancer and showed cystic duct invasion or concomitant xanthogranulomatous cholecystitis in permanent pathology. CONCLUSIONS: Gallbladder cancers on the cystic ductal end had worse postoperative oncologic outcomes compared with those on the fundal end.

Prognostic model for resected borderline and locally advanced pancreatic cancer after neoadjuvant chemotherapy.

BACKGROUND: The current AJCC 8th has been reported to have a poor ability to predict the prognosis in patients with resected borderline resectable pancreatic cancer and locally advanced pancreatic cancer following neoadjuvant chemotherapy. This study was aimed to develop an improved prognostic model by incorporating pathology and parameters of biologic response (BR). MATERIALS METHODS: A retrospective cohort study was conducted including patients who underwent curative-intent surgery following chemotherapy. We developed a modified ypT staging system and incorporated the BR, involving normalization of carbohydrate antigen 19-9 and reduction in the maximum standardized uptake value simultaneously after chemotherapy. The prognostic performance of the current pathologic system, modified pathologic system, and newly developed system incorporating pathology and BR were compared. RESULTS: In this study, 171 patients underwent surgery following chemotherapy. The modified T stage, which unified ypT2 and ypT3, demonstrated improved prognostic performance than the current staging system (area under the curve: 0.706 vs. 0.661). Biologic unresponsiveness was an independent prognostic factor for worse survival (hazard ratio 2.31, 95% confidence interval 1.50-3.55, P<0.001). The modified pathology with BR system demonstrated the highest discriminative ability in predicting 5-year overall survival than the current pathologic system (area under the curve: 0.785 vs. 0.661, P=0.010) and modified pathologic staging system (area under the curve: 0.785 vs. 0.706, P=0.002). CONCLUSIONS: The prognostic model, incorporating modified ypT staging and elevated carbohydrate antigen 19-9 levels and maximum standardized uptake value simultaneously, demonstrated improved results in predicting oncologic outcomes for patients who underwent surgery following neoadjuvant chemotherapy.

Metabolic tumor burden as a prognostic indicator after neoadjuvant chemotherapy in pancreatic cancer.

BACKGROUND: There is no standardized assessment for evaluating response although neoadjuvant chemotherapy (NAT) is widely accepted for borderline resectable or locally advanced pancreatic cancer (BRPC or LAPC). This study was aimed to evaluate NAT response using positron emission tomography with 2-deoxy-2-[fluorine-18]fluoro-D-glucose ( 18 F-FDG-PET/CT) parameters alongside carbohydrate antigen (CA) 19-9 levels. METHODS: Patients who underwent surgery after NAT for BRPC and LAPC between 2017 and 2021 were identified. The study assessed the prognostic value of PET-derived parameters after NAT, determining cutoff values using the K-adaptive partitioning method. It created four groups based on the elevation or normalization of PET parameters and CA19-9 levels, comparing survival between these groups. RESULTS: Of 200 eligible patients, FOLFIRINOX and gemcitabine-based NAT were administered in 167 and 34 patients, respectively (mean NAT cycles, 8.3). In a multivariate analysis, metabolic tumor volume (MTV) demonstrated the most robust performance in assessing response (HR 3.11, 95% CI 1.73-5.58, P <0.001) based on cut-off value of 2.4. Patients with decreased MTV had significantly better survival than those with elevated MTV among individuals with CA19-9 levels <37 IU/L (median survival; 35.5 vs. 20.9 mo, P <0.001) and CA19-9 levels ≥37 IU/L (median survival; 34.3 vs. 17.8 mo, P =0.03). In patients suspected to be Lewis antigen negative, predictive performance of MTV was found to be limited ( P =0.84). CONCLUSION: Elevated MTV is an influential prognostic factor for worse survival, regardless of post-NAT CA19-9 levels. These results could be helpful in identifying patients with a poor prognosis despite normalization of CA19-9 levels after NAT.

Orthotopic model of pancreatic cancer using CD34+ humanized mice and generation of tumor organoids from humanized tumors.

In pancreatic cancer (PC) as intractable solid cancer, current research is focused mainly on targeted immunotherapies such as antibodies and immune cell modulators. To identify promising immune-oncological agents, animal models that recapitulate the essential features of human immune status are essential. To this end, we constructed an orthotopic xenograft model using CD34+ human hematopoietic stem cell-based humanized NOD scid gamma mouse (NSG) mice injected with luciferase-expressing PC cell lines AsPC1 and BxPC3. The growth of orthotopic tumors was monitored using noninvasive multimodal imaging, while the subtype profiles of human immune cells in blood and tumor tissues were determined by flow cytometry and immunohistopathology. In addition, the correlations of blood and tumor-infiltrating immune cell count with tumor extracellular matrix density were calculated using Spearman's test. Tumor-derived cell lines and tumor organoids with continuous passage capacity in vitro were isolated from orthotopic tumors. It was further confirmed that these tumor-derived cells and organoids have reduced PD-L1 expression and are suitable for testing the efficacy of specific targeted immunotherapeutic agents. These animal and culture models could facilitate the development and validation of immunotherapeutic agents for intractable solid cancers including PC.

Evaluation of postoperative outcomes of minimally invasive distal pancreatectomy for left-sided pancreatic tumors based on the modified frailty index: a retrospective cohort study.

BACKGROUND: This study compared the postoperative outcomes of minimally invasive distal pancreatectomy (MIDP) for left-sided pancreatic tumors based on the modified frailty index (mFI). MATERIALS AND METHODS: This retrospective study included 2212 patients who underwent MIDP for left-sided pancreatic tumors between 2005 and 2019. Postoperative outcomes, including complications (morbidity and mortality), were analyzed using mFI, and the participants were divided into two groups: frail ( n =79) and nonfrail ( n =2133). A subanalysis of 495 MIDPs for pancreatic ductal adenocarcinoma was conducted to compare oncological outcomes. RESULTS: Clinically relevant postoperative pancreatic fistula was significantly higher in the frail group than in the nonfrail group. A significant between-group difference was observed in overall complications with Clavien-Dindo classification grade ≥III. Furthermore, the proportion of all complications before readmission was higher in the frail group than in the nonfrail group. Among all readmitted patients, the frail group had a higher number of grade ≥IV patients requiring ICU treatment. The frail group's 90-day mortality was 1.3%; the difference was statistically significant (nonfrail: 0.3%, P =0.021). In the univariate and multivariate logistic regression analyses, mFI ≥0.27 (odds ratio 3.231, 95% CI: 1.889-5.523, P <0.001), extended pancreatectomy, BMI ≥30 kg/m 2 , male sex, and malignancy were risk factors for Clavien-Dindo classification grade ≥III. CONCLUSION: mFI is a potential preoperative tool for predicting severe postoperative complications, including mortality, in patients who have undergone MIDP for left-sided tumors.

Laparoscopic versus open pancreaticoduodenectomy with major vein resection for pancreatic head cancer.

BACKGROUND/PURPOSE: Laparoscopic pancreaticoduodenectomy (PD) with major vein resection is a challenging procedure. Herein, we evaluated the feasibility and safety of laparoscopic vein resection in pancreatic head cancer with portal vein/superior mesenteric vein (PV/SMV) invasion, and compared the survival rate following laparoscopic surgery with that following open surgery. METHODS: We retrospectively reviewed the electronic medical records of all patients with pancreatic head cancer who underwent surgery performed by a single surgeon from January 2015 to December 2017. Kaplan-Meier curves were plotted to compare the disease-free survival, while Cox-proportional hazard models were used to analyze prognostic factors for survival. RESULTS: Among 76 patients, 63 underwent open PD and 13 underwent laparoscopic PD with PV/SMV resection. There was no significant difference in the rate of complications, including portal vein stenosis and portal vein thrombus, recurrence of tumors, or pathological outcomes after surgery between the groups. There was also no significant difference in disease-free survival (p = .803) between the two groups. Additionally, the surgical method was not an independent prognostic factor for disease-free survival. CONCLUSIONS: Laparoscopic PD with major vein resection can be feasibly performed in select patients with abutment and focal narrowing of the PV/SMV in pancreatic head cancer.

Intercellular cross-talk through lineage-specific gap junction of cancer-associated fibroblasts related to stromal fibrosis and prognosis.

Stromal fibrosis in cancer is usually associated with poor prognosis and chemotherapy resistance. It is thought to be caused by fibroblasts; however, the exact mechanism is not yet well understood. The study aimed to identify lineage-specific cancer-associated fibroblast (CAF) subgroup and their associations with extracellular matrix remodeling and clinical significances in various tumor types using single-cell and bulk RNA sequencing data. Through unsupervised clustering, six subclusters of CAFs were identified, including a cluster with exclusively high gap junction protein beta-2 (GJB2) expression. This cluster was named GJB2-positive CAF. It was found to be a unique subgroup of terminally differentiated CAFs associated with collagen gene expression and extracellular matrix remodeling. GJB2-positive CAFs showed higher communication frequency with vascular endothelial cells and cancer cells than GJB2-negative CAFs. Moreover, GJB2 was poorly expressed in normal tissues, indicating that its expression is dependent on interaction with other cells, including vascular endothelial cells and cancer cells. Finally, the study investigated the clinical significance of GJB2 signature score for GJB2-positive CAFs in cancer and found a correlation with poor prognosis. These results suggest that GJB2-positive CAF is a unique fibroblast subtype involved in extracellular matrix remodeling, with significant clinical implications in cancer.