YAP/BRD4-controlled ROR1 promotes tumor-initiating cells and hyperproliferation in pancreatic cancer.

Tumor-initiating cells are major drivers of chemoresistance and attractive targets for cancer therapy, however, their identity in human pancreatic ductal adenocarcinoma (PDAC) and the key molecules underlying their traits remain poorly understood. Here, we show that a cellular subpopulation with partial epithelial-mesenchymal transition (EMT)-like signature marked by high expression of receptor tyrosine kinase-like orphan receptor 1 (ROR1) is the origin of heterogeneous tumor cells in PDAC. We demonstrate that ROR1 depletion suppresses tumor growth, recurrence after chemotherapy, and metastasis. Mechanistically, ROR1 induces the expression of Aurora kinase B (AURKB) by activating E2F through c-Myc to enhance PDAC proliferation. Furthermore, epigenomic analyses reveal that ROR1 is transcriptionally dependent on YAP/BRD4 binding at the enhancer region, and targeting this pathway reduces ROR1 expression and prevents PDAC growth. Collectively, our findings reveal a critical role for ROR1high cells as tumor-initiating cells and the functional importance of ROR1 in PDAC progression, thereby highlighting its therapeutic targetability.

Retinoids rescue ceruloplasmin secretion and alleviate oxidative stress in Wilson's disease-specific hepatocytes.

Wilson's disease (WD) is a copper metabolic disorder caused by a defective ATP7B function. Conventional therapies cause severe side effects and significant variation in efficacy, according to cohort studies. Thus, exploring new therapeutic approaches to prevent progression to liver failure is urgent. To study the physiology and pathology of WD, immortalized cell lines and rodent WD models have been used conventionally; however, a large gap remains among different species as well as in genetic backgrounds among individuals. We generated induced pluripotent stem cells (iPSCs) from four WD patients carrying compound heterozygous mutations in the ATP7B gene. ATP7B loss- and gain-of-functions were further manifested with ATP7B-deficient iPSCs and heterozygously corrected R778L WD patient-derived iPSCs using CRISPR-Cas9-based gene editing. Although the expression of ATP7B protein varied among WD-specific hepatocytes differentiated from these iPSCs, the expression and secretion of ceruloplasmin (Cp), a downstream copper carrier in plasma, were consistently decreased in WD patient-derived and ATP7B-deficient hepatocytes. A transcriptome analysis detected abnormalities in the retinoid signaling pathway and lipid metabolism in WD-specific hepatocytes. Drug screening using WD patient-derived hepatocytes identified retinoids as promising candidates for rescuing Cp secretion. All-trans retinoic acid also alleviates reactive oxygen species production induced by lipid accumulation in WD-specific hepatocytes treated with oleic acid. These patient-derived iPSC-based hepatic models function as effective platforms for the development of potential therapeutics for hepatic steatosis in WD and other fatty liver diseases.

Preoperative risk factors for 90-day postoperative mortality outcome in patients with non-occlusive mesenteric ischemia.

PURPOSE: The mortality rate for non-occlusive mesenteric ischemia remains high even after patients survive the acute postoperative period with tremendous treatment efforts, including emergency surgery, which is challenging. The aim of this study was to explore the preoperative risk factors for 90-day postoperative mortality in patients with non-occlusive mesenteric ischemia. METHODS: This single-center, retrospective cohort study included patients diagnosed with non-occlusive mesenteric ischemia who underwent emergency surgery between August 2014 and January 2023. All patients were divided into survival-to-discharge and mortality outcome groups at the 90-day postoperative follow-up. Preoperative factors, including comorbidities, preoperative status of vital signs and consciousness, blood gas analysis, blood test results, and computed tomography, were compared between the two groups. RESULTS: Twenty patients were eligible, and 90-day mortality was observed in 10 patients (50%). The mortality outcome group had significantly lower HCO3- (20.9 vs. 14.6, p = 0.006) and higher lactate (4.4 vs. 9.4, p = 0.023) levels than did the survival outcome group. The median postoperative time to death was 19 [2-69] days, and five patients (50%) died after postoperative day 30, mainly because hemodialysis was discontinued because of hemodynamic instability in patients requiring hemodialysis. CONCLUSION: Low preoperative HCO3- and high lactate levels may be preoperative risk factors for 90-day postoperative mortality in patients with non-occlusive mesenteric ischemia. However, patients on hemodialysis die from discontinuing hemodialysis even after surviving the acute postoperative phase. Therefore, indications for emergency surgery in patients with risk factors for postoperative mortality should be carefully determined.

Comparison of proton-based definitive chemoradiotherapy and surgery-based therapy for esophageals cell carcinoma: a multi-center retrospective Japanese cohort study.

BACKGROUND: Proton-based, definitive chemoradiotherapy (P-CRT) for esophageal squamous cell carcinoma (ESCC) previously showed comparable survival outcomes with the surgery-based therapy, i.e., neoadjuvant chemotherapy followed by esophagectomy (NAC-S), in a single-institutional study. This study aimed to validate this message in a Japanese multicenter study. METHODS: Eleven Japanese esophageal cancer specialty hospitals have participated. A total of 518 cases with clinical Stage I-IVA ESCC between 2010 and 2019, including 168 P-CRT and 350 NAC-S patients, were enrolled and long-term outcomes were evaluated. Propensity-score weighting analyses with overlap weighting for confounding adjustment were used. RESULTS: The 3-year overall survival (OS) of the P-CRT group was equivalent to the NAC-S group (74.8% vs. 72.7%, hazard ratio [HR]: 0.87, 95% confidence interval [CI]: 0.61-1.25). Although, the 3-year P-CRT group progression-free survival (PFS) was inferior to the NAC-S group (51.4% vs. 59.6%, HR 1.39, 95% CI 1.04-1.85), the progression P-CRT group cases showed better survival than the NAC-S group (HR 0.58, 95% CI 0.38-0.88), largely because of salvage surgery or endoscopic submucosal dissection for local progression. The survival advantage of P-CRT over NAC-S was more pronounced in the cT1-2 (HR 0.61, 95% CI 0.29-1.26) and cStage I-II (HR 0.50, 95% CI 0.24-1.07) subgroups, although this trend was not evident in other populations, such as cT3-4 and cStage III-IVA. CONCLUSIONS: Proton-based CRT for ESCC showed equivalent OS to surgery-based therapy. Especially for patients with cT1-2 and cStage I-II disease, proton-based CRT has the potential to serve as a first-line treatment.

rBC2LCN-reactive SERPINA3 is a glycobiomarker candidate for pancreatic ductal adenocarcinoma.

Early detection is urgently needed to improve the patient's pancreatic ductal adenocarcinoma (PDAC) survival. Previously, we identified a novel tumor-associated glycan, H-type3, which is expressed on PDAC cells and is detected by rBC2LCN (recombinant N-terminal domain of BC2L-C identified from Burkholderia cenocepacia) lectin. Here, we identified that SERPINA3 is an rBC2LCN-reactive glycoprotein (BC2-S3) secreted from PDAC cells into the blood in patients with PDAC by liquid chromatography-tandem mass spectrometry analysis and lectin blotting. In immune staining, BC2-S3 was detected specifically in the tumor but not in normal tissues of PDAC. Lectin-ELISA was then developed to measure the serum level of BC2-S3 in healthy control (HC, n = 99) and patients with PDAC (n = 88). BC2-S3 exhibited higher in patients with PDAC than in those with HC. BC2-S3 showed similar diagnostic performance in all stages of PDAC (stages IA-IV, true positive rate = 76.1%, true negative rate = 81.8%) to CA19-9 (72.7%, 75.8%). Remarkably, BC2-S3 showed a significantly higher detection rate (89.7%) for early stage PDAC (IA-IIA) than CA19-9 (62.1%, P = 0.029). The combination of BC2-S3 and CA19-9 further improved the diagnostic ability for all stages of PDAC (81.8%, 87.9%). In conclusion, BC2-S3 is a glycobiomarker candidate for PDAC.

Lectin-based phototherapy targeting cell surface glycans for pancreatic cancer.

Pancreatic ductal adenocarcinoma (PDAC) is resistant to current treatments but lectin-based therapy targeting cell surface glycans could be a promising new horizon. Here, we report a novel lectin-based phototherapy (Lec-PT) that combines the PDAC targeting ability of rBC2LCN lectin to a photoabsorber, IRDye700DX (rBC2-IR700), resulting in a novel and highly specific near-infrared, light-activated, anti-PDAC therapy. Lec-PT cytotoxicity was first verified in vitro with a human PDAC cell line, Capan-1, indicating that rBC2-IR700 is only cytotoxic upon cellular binding and exposure to near-infrared light. The therapeutic efficacy of Lec-PT was subsequently verified in vivo using cell lines and patient-derived, subcutaneous xenografting into nude mice. Significant accumulation of rBC2-IR700 occurs as early as 2 hours postintravenous administration while cytotoxicity is only achieved upon exposure to near-infrared light. Repeated treatments further slowed tumor growth. Lec-PT was also assessed for off-target toxicity in the orthotopic xenograft model. Shielding of intraperitoneal organs from near-infrared light minimized off-target toxicity. Using readily available components, Lec-PT specifically targeted pancreatic cancer with high reproducibility and on-target, inducible toxicity. Rapid clinical development of this method is promising as a new modality for treatment of pancreatic cancer.

Novel positron emission tomography imaging targeting cell surface glycans for pancreatic cancer: 18 F-labeled rBC2LCN lectin.

Advancement in early detection modalities will greatly improve the overall prognoses of pancreatic ductal adenocarcinoma (PDAC). For this purpose, we report a novel class of tumor-specific probes for positron emission tomography (PET) based on targeting cell surface glycans. The PDAC-targeting ability of rBC2LCN lectin, combined with fluorine-18 (18 F) ([18 F]FB-rBC2LCN), resulted in reproducible, high-contrast PET imaging of tumors in a PDAC xenograft mouse model. [18 F]N-succinimidyl-4-fluorobenzoate ([18 F]SFB) was conjugated to rBC2LCN, and [18 F]FB-rBC2LCN was successfully prepared with a radiochemical purity >95%. Cell binding and uptake revealed that [18 F]FB-rBC2LCN binds to H-type-3-positive Capan-1 pancreatic cancer cells. As early as 60 min after [18 F]FB-rBC2LCN (0.34 ± 0.15 MBq) injection into the tail vein of nude mice subcutaneously bearing Capan-1 tumors, tumor uptake was high (6.6 ± 1.8 %ID/g), and the uptake increased over time (8.8 ± 1.9 %ID/g and 11 ± 3.2 %ID/g at 150 and 240 min after injection, respectively). Tumor-to-muscle ratios increased over time, up to 19 ± 1.8 at 360 min. High-contrast PET imaging of tumors relative to background muscle was also achieved as early as 60 min after injection of [18 F]FB-rBC2LCN (0.66 ± 0.12 MBq) and continued to increase up to 240 min. Our 18 F-labeled rBC2LCN lectin warrants further clinical development to improve the accuracy and sensitivity of early-stage pancreatic cancer detection.

Cloning, DNA sequence, and expression of flagellins from high and low virulence strains of Edwardsiella tarda and their macrophage-stimulating activities.

Edwardsiella tarda is a causative pathogen of edwardsiellosis in fish. Our previous studies on high (NUF251) and low (NUF194) virulent strains of E. tarda demonstrated that NUF251 strain induced significantly higher levels of NO and TNF-α from fish and mouse macrophages than NUF194 strain. Subsequent studies suggested that a flagellin-like protein secreted from E. tarda might be a responsible factor for the macrophage-stimulating activities. To evaluate the activities of flagellins of E. tarda, in this study, the flagellin genes of NUF251 and NUF194 strains were isolated by PCR and cloned into pQE-30 and pCold I expression vectors, and then the recombinant flagellins of two strains were overexpressed in E. coli JM109 and pG-Tf/BL21, respectively. The molecular weight of the purified recombinant flagellins of NUF251 and NUF194 strains were estimated to be 45 kDa and 37 kDa, respectively on SDS-PAGE analysis. Referring the three-dimensional structure of Salmonella flagellin, which has been reported to have 4 domains (D0, D1, D2, and D3), high sequence homology between two flagellins of E. tarda was observed at conservative domain (D0 and D1) regions, whereas the sequences equivalent to D2 and D3 domains were different, and even equivalent to 57 amino acids were deleted in NUF194. Both recombinant flagellins induced NO production, mRNA expression level of inducible NO synthase (iNOS), and intercellular ROS production in mouse macrophage cell line RAW264.7 cells. Also, the secretion of TNF-α and its mRNA expression level were increased by treatment of both recombinant flagellins. These results indicate that the recombinant flagellins from different virulent E. tarda strains can stimulate macrophages with nearly equal levels as judged by the parameters tested, even though they are differences in the structure and molecular weight, suggesting that conservative D0 and D1 domains are sufficient structural elements for the recombinant flagellins to induce a certain level of macrophage-stimulation in vitro. Further studies are necessary focusing on the role of D2 and D3 domain regions of the recombinant flagellins as macrophage-stimulating agent as well as their influence on host immune system in vivo.

Triple modal treatment comprising with proton beam radiation, hyperthermia, and gemcitabine/nab-paclitaxel for locally advanced pancreatic cancer: a phase I/II study protocol (TT-LAP trial).

BACKGROUND: Locally advanced pancreatic ductal adenocarcinoma (PDAC), accounting for about 30% of PDAC patients, is difficult to cure by radical resection or systemic chemotherapy alone. A multidisciplinary strategy is required and our TT-LAP trial aims to evaluate whether triple-modal treatment with proton beam therapy (PBT), hyperthermia, and gemcitabine plus nab-paclitaxel is a safe and synergistically effective treatment for patients with locally advanced PDAC. METHODS: This trial is an interventional, open-label, non-randomized, single-center, single-arm phase I/II clinical trial organized and sponsored by the University of Tsukuba. Eligible patients who are diagnosed with locally advanced pancreatic cancer, including both borderline resectable (BR) and unresectable locally advanced (UR-LA) patients, and selected according to the inclusion and exclusion criteria will receive triple-modal treatment consisting of chemotherapy, hyperthermia, and proton beam radiation. Treatment induction will include 2 cycles of chemotherapy (gemcitabine plus nab-paclitaxel), proton beam therapy, and 6 total sessions of hyperthermia therapy. The initial 5 patients will move to phase II after adverse events are verified by a monitoring committee and safety is ensured. The primary endpoint is 2-year survival rate while secondary endpoints include adverse event rate, treatment completion rate, response rate, progression-free survival, overall survival, resection rate, pathologic response rate, and R0 (no pathologic cancer remnants) rate. The target sample size is set at 30 cases. DISCUSSION: The TT-LAP trial is the first to evaluate the safety and effectiveness (phases1/2) of triple-modal treatment comprised of proton beam therapy, hyperthermia, and gemcitabine/nab-paclitaxel for locally advanced pancreatic cancer. ETHICS AND DISSEMINATION: This protocol was approved by the Tsukuba University Clinical Research Review Board (reference number TCRB22-007). Results will be analyzed after study recruitment and follow-up are completed. Results will be presented at international meetings of interest in pancreatic cancer plus gastrointestinal, hepatobiliary, and pancreatic surgeries and published in peer-reviewed journals. TRIAL REGISTRATION: Japan Registry of Clinical Trials, jRCTs031220160. Registered 24 th June 2022, https://jrct.niph.go.jp/en-latest-detail/jRCTs031220160 .

Total Superior Mesenteric Artery Nerve Plexus Preservation During Pancreaticoduodenectomy for Pancreatic Cancer.

BACKGROUND: Superior mesenteric artery (SMA) nerve plexus (PLsma) dissection has been performed to achieve R0 resection in pancreaticoduodenectomy (PD) for pancreatic ductal adenocarcinoma (PDAC) in high-volume centers. However, full-extent PLsma preservation in PD is employed in our institution. The feasibility of the PLsma preservation strategy was investigated. METHODS: Between January 2010 and December 2020, 156 patients underwent PLsma preservation PD for PDAC at our institution. Of these, 118 patients had resectable PDAC (R group) and 38 patients had borderline resectable artery (BR-A group). Clinical and oncological outcomes focusing on local recurrence, patient prognoses, and morbidities (including postoperative refractory diarrhea) were retrospectively analyzed and our postoperative outcomes were compared with those of other institutions. RESULTS: Pathological R0 resection by PLsma preservation PD was achieved in 96 R group patients (81.4%) and 27 BR-A group patients (71.1%). The median postoperative hospital stay was 15.0 days in both groups. Local site-only recurrence was observed in 10.2% (12/118) of R-group and 10.5% (4/38) of BR-A-group patients, whereas distant site-only recurrence occurred in 21.2% (25/118) of R-group and 28.9% (11/38) of BR-A-group patients. Median survival times were 64.3 months (R group) and 35.4 months (BR-A group, p = 0.07). Median disease-free survival (DFS) times were 31.0 months (R group) and 12.0 months (BR-A group). No diarrhea requiring opioids was observed in either group. These results were equal or superior to those of PLsma dissection PD in other institutions. CONCLUSIONS: PLsma preservation in PD was feasible compared to PLsma dissection in recurrence and overall survival.

A comparative study of stoma-related complications from diverting loop ileostomy or colostomy after colorectal surgery.

PURPOSE: Even though minor, stoma-related complications significantly impact quality of life, they are often excluded from clinical analyses that compare short-term postoperative outcomes of loop ileostomy and loop colostomy. This study compares stoma-related complications between loop ileostomy and loop colostomy after rectal resection, including minor complications, and discusses the characteristics of diverting stoma types. METHODS: A retrospective review was conducted in patients who underwent diverting stoma construction after rectal resection. Data on patient background and postoperative short-term outcomes, including stoma-related complications and morbidity after stoma closure, were collected and compared between loop ileostomy and loop colostomy groups. Morbidities of all severity grades were targeted for analysis. RESULTS: A total of 47 patients (27 loop ileostomy, 20 loop colostomy) underwent diverting stoma construction following rectal resection. Overall stoma-related complications, incidence of skin irritation, high-output stoma, and outlet obstruction were significantly higher in the loop ileostomy group but high-output stoma and outlet obstruction were absent in the loop colostomy group. Regarding morbidity after stoma closure, operation times and surgical site infections were significantly higher in the loop colostomy group while anastomotic leakage after diverting stoma closure occurred (2 cases; 15%) in the loop colostomy group but not the loop ileostomy group. CONCLUSION: Because stoma-related complications were significantly higher in the loop ileostomy group, and even these minor complications may impair QOL, early loop ileostomy closure is recommended. For loop colostomy, stoma-related morbidities are lower but post-closure leakage is a calculated risk.

Clinical advantage of transmediastinal esophagectomy in terms of postoperative respiratory complications.

BACKGROUND: Although the transmediastinal approach as a radical esophagectomy for esophageal carcinoma patients has attracted attention, its advantages over the transthoracic approach remain unclear. This study aimed to evaluate the efficacy of transmediastinal esophagectomy (TME) in terms of postoperative respiratory complications compared to that of open transthoracic esophagectomy (TTE). METHODS: We reviewed patients with thoracic and abdominal esophageal carcinoma who underwent TME or TTE between February 2014 and November 2021. We compared postoperative respiratory complications as the primary outcome. The secondary outcomes included perioperative operation time, blood loss, postoperative complications, and the number of harvested mediastinal lymph nodes. RESULTS: Overall, 60 and 54 patients underwent TME and TTE, respectively. The baseline characteristics were similar between the two groups, except for age and histological type. There were no intraoperative lethal complications in either group. The incidence of respiratory complications was significantly lower in the TME group than in the TTE group (6.7 vs. 22.2%, p = 0.03). The TME group had a shorter operation time (403 vs. 451 min, p < 0.01), less blood loss (107 vs. 253 mL, p < 0.01), and slightly higher anastomotic leakage (11.7 vs. 5.6%, p = 0.33). The number of harvested lymph nodes was similar in both groups (24 vs. 26, p = 0.10). Multivariate analysis revealed that TME is an independent factor in reducing respiratory complications (odds ratio = 0.27, p = 0.04). CONCLUSIONS: TME for esophageal carcinoma was performed safely. TME was superior to TTE in terms of postoperative respiratory complications; however, the relatively higher frequency of anastomotic leakage should be considered and requires further evaluation.

[A case of multiple duodenal gastrointestinal stromal tumors associated with neurofibromatosis type 1].

Gastrointestinal stromal tumors (GISTs) associated with von Recklinghausen's disease (neurofibromatosis type 1 [NF1]) have different pathogenesis and characteristics from common GISTs. Furthermore, no treatment strategy for this type of GIST has been established. This study presents the case of a 76-year-old man previously diagnosed with NF1 who was later diagnosed with GISTs. A resection of the horizontal leg of the duodenum was performed, and no recurrence was observed 18 months after the surgery.

Usefulness of Human Jejunal Spheroid-Derived Differentiated Intestinal Epithelial Cells for the Prediction of Intestinal Drug Absorption in Humans.

This study aimed to demonstrate the usefulness of human jejunal spheroid-derived differentiated intestinal epithelial cells as a novel in vitro model for clarifying the impact of intestinal drug-metabolizing enzymes and transporters on the intestinal absorption of substrate drugs in humans. Three-dimensional human intestinal spheroids were successfully established from surgical human jejunal specimens and expanded for a long period using L-WRN-conditioned medium, which contains Wnt3a, R-spondin 3, and noggin. The mRNA expression levels of intestinal pharmacokinetics-related genes in the human jejunal spheroid-derived differentiated intestinal epithelial cells were drastically increased over a 5-day period after seeding compared with those in human jejunal spheroids and were approximately the same as those in human jejunal tissue over a culture period of at least 13 days. Activities of typical drug-metabolizing enzymes [cytochrome P450 (CYP) 3A, CYP2C9, uridine 5'-diphospho-glucuronosyltransferase 1A, and carboxylesterase 2] and uptake/efflux transporters [peptide transporter 1/solute carrier 15A1], P-glycoprotein, and breast cancer resistance protein) in the differentiated cells were confirmed. Furthermore, intestinal availability (Fg) values estimated from the apical-to-basolateral permeation clearance across cell monolayer showed a good correlation with the in vivo Fg values in humans for five CYP3A substrate drugs (Fg range, 0.35-0.98). In conclusion, the functions of major intestinal drug-metabolizing enzymes and transporters could be maintained in human jejunal spheroid-derived differentiated intestinal epithelial cells. This model would be useful for the quantitative evaluation of the impact of intestinal drug-metabolizing enzymes and transporters on the intestinal absorption of substrate drugs in humans. SIGNIFICANCE STATEMENT: Limited information is available regarding the quantitative prediction of the impact of drug-metabolizing enzymes and transporters on the human intestinal absorption of substrates using in vitro assays with differentiated cells derived from human intestinal spheroids/organoids. This study confirmed the functions of typical drug-metabolizing enzymes and transporters in human jejunal spheroid-derived differentiated intestinal epithelial cells and demonstrated that intestinal availability (Fg) estimated from apical-to-basolateral permeation clearance across cell monolayers showed a good correlation with in vivo human Fg for CYP3A substrates.

Increased intrarenal post-glomerular blood flow is a key condition for the development of calcineurin inhibitor-induced renal tubular acidosis in kidney transplant recipients.

BACKGROUND: Hyperchloremic metabolic acidosis (HCMA) from renal tubular acidosis (RTA) is common in kidney transplant (KT) recipients. Calcineurin inhibitors (CNIs) are a potential cause of RTA, and whether HCMA is a determinant of poor graft prognosis is controversial. METHODS: The subjects were living-donor KT recipients (LDKTRs, n = 47) and matched donors (n = 43). All cases of rejection, extrarenal causes, and respiratory disorders were excluded. HCMA was defined as having a [Na+]-[Cl- ] value of ≤34 or starting alkalization. We determined the potential causes of HCMA in LDKTRs at 3 months (m) and 1 year (y) post-KT. We examined renal hemodynamic parameters in 26 LDKTRs at 1 y post-KT: namely, glomerular filtration rate (GFR), renal plasma flow (RPF), filtration fraction (FF; GFR/RPF) and pre-/post-glomerular vascular resistance (pre-/postVR). RESULTS: The HCMA incidence in the 3-m post-KT LDKTR group was higher than that of the donors (51.0% vs. 6.9%, p < 0.001, adjusted odds ratio: 6.7-15.7). Among adjusted factors, the most dominant HCMA contributor was low hemoglobin concentration (Hb ≤ 12 g/dl). Compared to non-HCMA cases, HCMA patients had low FF and low post-VR (p = 0.008, 0.003, respectively) suggesting increased intrarenal post-glomerular blood flow. The high pathological score of alternative arteriolar hyalinosis (aah) ≥2 was a significant HCMA risk. The tacrolimus trough level was not high in HCMA but was significantly high in HCMA in the low post-VR setting (p = 0.002). CONCLUSION: Among LDKTRs, low hemoglobin level is an important contributor to the manifestation of HCMA in the induction period, and increased intrarenal post-glomerular blood flow is a key condition for the development of CNI-induced RTA.

A Comparative Study of Patient-Derived Tumor Models of Pancreatic Ductal Adenocarcinoma Involving Orthotopic Implantation.

BACKGROUND: Pancreatic ductal adenocarcinoma (PDA) is associated with very poor prognoses. Therefore, new therapies and preclinical models are urgently needed. In the present study, we sought to develop more realistic experimental models for use in PDA research. METHODS: We developed patient-derived xenografts (PDXs), established PDX-derived cell lines (PDCLs), and generated cell line-derived xenografts (CDXs), which we integrated to create 13 matched "trios" - i.e., patient-derived tumor models of PDA. We then compared and contrasted histological and molecular alterations between these three model systems. RESULTS: Orthotopic implantation (OI) of the PDCLs resulted in tumorigenesis and metastases to the liver and peritoneum. Morphological comparisons of OI-CDXs and OI-PDXs with passaged tumors revealed that the histopathological features of the original tumor were maintained in both models. Molecular alterations in PDX tumors (including those to KRAS, TP53, SMAD4, and CDKN2A) were similar to those in the respective PDCLs and CDX tumors. When gene expression levels in the PDCLs, ectopic tumors, and OI tumors were compared, the distant metastasis-promoting gene CXCR4 was specifically upregulated in OI tumors, whose immunohistochemical profiles suggested epithelial-mesenchymal transition and adeno-squamous trans-differentiation. CONCLUSION: These patient-derived tumor models provide useful tools for monitoring responses to antineoplastic agents and for studying PDA biology.

Glycan expression profile of signet ring cell gastric cancer cells and potential applicability of rBC2LCN-targeted lectin drug conjugate therapy.

BACKGROUND: Signet ring cell carcinoma (SRC) is a distinct subtype of gastric cancer (GC); however, the specific characteristics of cancer cell surface glycans and glycosylation remain unclear. In this study, we investigated SRC-specific glycans using lectin microarray and evaluated the potential applicability of a glycan-targeting therapy. METHODS: SRC cell lines (NUGC-4 and KATO-III) and non-SRC (NSRC) cell lines (NCI-N87, SNU-1, and MKN-45) were subjected to lectin microarray analysis to identify the SRC-specific glycans. Additionally, we performed immunohistochemical lectin staining and evaluated the anti-tumor effects of lectin drug conjugates (LDCs) using high-affinity lectins for SRC. RESULTS: Among the 96 lectins tested, 11 high-affinity and 8 low-affinity lectins were identified for SRC. Glycan-binding motifs varied in the high-affinity lectins, but 5 (62.5%) low-affinity lectins bound the same glycan structure, α2-6-linked sialic acids. The ratio of signal intensity in SRC to NSRC (SRC/NSRC) was highest in the rBC2LCN lectin (1.930-fold), followed by the BPL lectin (1.786-fold). rBC2LCN lectin showed high affinity for both SRC cell lines and one of the three NSRC cell lines (NCI-N87). The therapeutic effects of the LDC, rBC2LCN-PE38 (rBC2LCN, and Pseudomonas exotoxin A), showed cytocidal effects in vitro and tumor regression in in vivo mouse xenograft models. CONCLUSION: We reported specific glycan profiles in SRC cells, showing reduced α2-6-linked sialic acids. Additionally, we found a targeted therapy using rBC2LCN lectin might be applicable as an alternative treatment option for patients with SRC.

Deep learning-based automatic surgical step recognition in intraoperative videos for transanal total mesorectal excision.

BACKGROUND: Dividing a surgical procedure into a sequence of identifiable and meaningful steps facilitates intraoperative video data acquisition and storage. These efforts are especially valuable for technically challenging procedures that require intraoperative video analysis, such as transanal total mesorectal excision (TaTME); however, manual video indexing is time-consuming. Thus, in this study, we constructed an annotated video dataset for TaTME with surgical step information and evaluated the performance of a deep learning model in recognizing the surgical steps in TaTME. METHODS: This was a single-institutional retrospective feasibility study. All TaTME intraoperative videos were divided into frames. Each frame was manually annotated as one of the following major steps: (1) purse-string closure; (2) full thickness transection of the rectal wall; (3) down-to-up dissection; (4) dissection after rendezvous; and (5) purse-string suture for stapled anastomosis. Steps 3 and 4 were each further classified into four sub-steps, specifically, for dissection of the anterior, posterior, right, and left planes. A convolutional neural network-based deep learning model, Xception, was utilized for the surgical step classification task. RESULTS: Our dataset containing 50 TaTME videos was randomly divided into two subsets for training and testing with 40 and 10 videos, respectively. The overall accuracy obtained for all classification steps was 93.2%. By contrast, when sub-step classification was included in the performance analysis, a mean accuracy (± standard deviation) of 78% (± 5%), with a maximum accuracy of 85%, was obtained. CONCLUSIONS: To the best of our knowledge, this is the first study based on automatic surgical step classification for TaTME. Our deep learning model self-learned and recognized the classification steps in TaTME videos with high accuracy after training. Thus, our model can be applied to a system for intraoperative guidance or for postoperative video indexing and analysis in TaTME procedures.

Preoperative CA19-9 is a prognostic factor in pT3N0 gastric cancer patients undergoing curative resection.

BACKGROUND: The standard treatment for pT3N0 gastric cancer (GC) in Japanese guidelines is radical surgery without adjuvant chemotherapy. However, certain percentages of these patients develop recurrences; therefore, detecting the high-risk subgroup of recurrence may contribute to improve patient's outcome by adjuvant chemotherapy. In this study, we aimed to identify a predictive indicator of poor prognosis in pT3N0 GC. METHODS: Eighty-one patients who were diagnosed as pT3N0 GC after curative surgical resection and had not received adjuvant chemotherapy were included. The clinicopathological factors and laboratory parameters were evaluated by univariate and multivariate analyses to identify prognostic factors of tumor recurrence. Survival analysis was performed by Kaplan-Meier method. RESULTS: Male (P = 0.027), a high body mass index (BMI) (P = 0.031), a high CA19-9 value (P = 0.025), and a lower number of retrieved lymph nodes (P = 0.018) were found to be significantly associated with a shorter recurrence free survival (RFS). In a multivariate analysis, high CA19-9 value (> 37 U/ml) [(hazard ratio (HR): 3.326; 95% confidence interval (CI): 1.044 to 10.596; P = 0.042] was found to be an independent predictor of RFS. CONCLUSION: The preoperative high CA19-9 value is considered a useful prognostic marker for predicting cancer recurrence after curative surgery in pT3N0 GC patients. For those patients, adjuvant chemotherapy might be considered to improve the survival outcome.

Prevalence of work-related musculoskeletal disorders among general surgeons in Japan.

PURPOSE: General surgeons are at high risk for work-related musculoskeletal disorders (WRMSDs), especially in their neck and back. The prevalence and risk factors for surgeons' WRMSDs in Japan have not been well surveyed. METHODS: A cross-sectional questionnaire survey on WRMSDs was conducted among general surgeons in Japan. Surgeons were asked about the presence and degree of neck, shoulder, and back disability in relation to open and laparoscopic surgery. RESULTS: The questionnaire was sent to 174 general surgeons in 21 hospitals and 106 (60.9%) responded. The prevalence of WRMSDs in the last month was 65.1%, and the prevalence at least once in a lifetime was 79.2%. The rate of WRMSDs of the neck and back was higher after open surgery (44.3%, 42.5%) than after laparoscopic surgery (28.2%, 31.1%), but there was no marked difference in shoulder pain. Age was the strongest risk factor for WRMSDs, and the pain scores, prevalence of chronic pain, and rate of WRMSD-related absence from work tended to increase with age. CONCLUSION: A questionnaire survey of surgeons in Japan showed that about 80% of surgeons suffer from WRMSDs. Countermeasures for WRMSDs among surgeons are urgently desired to ensure that limited numbers of surgeons work in the operating theatre throughout their career. CLINICAL TRIAL REGISTRATION: Registry name: a survey of surgeons' musculoskeletal pain associated with performing surgery. University of Tsukuba Institutional Review Board registration number: 1519.