Impaired tumor immune response in metastatic tumors is a selective pressure for neutral evolution in CRC cases.

A Darwinian evolutionary shift occurs early in the neutral evolution of advanced colorectal carcinoma (CRC), and copy number aberrations (CNA) are essential in the transition from adenoma to carcinoma. In light of this primary evolution, we investigated the evolutionary principles of the genome that foster postoperative recurrence of CRC. CNA and neoantigens (NAG) were compared between early primary tumors with recurrence (CRCR) and early primary tumors without recurrence (precancerous and early; PCRC). We compared CNA, single nucleotide variance (SNV), RNA sequences, and T-cell receptor (TCR) repertoire between 9 primary and 10 metastatic sites from 10 CRCR cases. We found that NAG in primary sites were fewer in CRCR than in PCRC, while the arm level CNA were significantly higher in primary sites in CRCR than in PCRC. Further, a comparison of genomic aberrations of primary and metastatic conditions revealed no significant differences in CNA. The driver mutations in recurrence were the trunk of the evolutionary phylogenic tree from primary sites to recurrence sites. Notably, PD-1 and TIM3, T cell exhaustion-related molecules of the tumor immune response, were abundantly expressed in metastatic sites compared to primary sites along with the increased number of CD8 expressing cells. The postoperative recurrence-free survival period was only significantly associated with the NAG levels and TCR repertoire diversity in metastatic sites. Therefore, CNA with diminished NAG and diverse TCR repertoire in pre-metastatic sites may determine postoperative recurrence of CRC.

Convergent genomic diversity and novel BCAA metabolism in intrahepatic cholangiocarcinoma.

BACKGROUND: Driver alterations may represent novel candidates for driver gene-guided therapy; however, intrahepatic cholangiocarcinoma (ICC) with multiple genomic aberrations makes them intractable. Therefore, the pathogenesis and metabolic changes of ICC need to be understood to develop new treatment strategies. We aimed to unravel the evolution of ICC and identify ICC-specific metabolic characteristics to investigate the metabolic pathway associated with ICC development using multiregional sampling to encompass the intra- and inter-tumoral heterogeneity. METHODS: We performed the genomic, transcriptomic, proteomic and metabolomic analysis of 39-77 ICC tumour samples and eleven normal samples. Further, we analysed their cell proliferation and viability. RESULTS: We demonstrated that intra-tumoral heterogeneity of ICCs with distinct driver genes per case exhibited neutral evolution, regardless of their tumour stage. Upregulation of BCAT1 and BCAT2 indicated the involvement of 'Val Leu Ile degradation pathway'. ICCs exhibit the accumulation of ubiquitous metabolites, such as branched-chain amino acids including valine, leucine, and isoleucine, to negatively affect cancer prognosis. We revealed that this metabolic pathway was almost ubiquitously altered in all cases with genomic diversity and might play important roles in tumour progression and overall survival. CONCLUSIONS: We propose a novel ICC onco-metabolic pathway that could enable the development of new therapeutic interventions.

Effect of duration of adjuvant chemotherapy with S-1 (6 versus 12 months) for resected pancreatic cancer: the multicenter clinical randomized phase II postoperative adjuvant chemotherapy S-1 (PACS-1) trial.

BACKGROUND: Six-month adjuvant chemotherapy with S-1 is standard care for resected pancreatic cancer in Japan; however, the optimal duration has not been established. We aimed to evaluate the impact of duration of adjuvant chemotherapy with S-1. METHODS: We performed a multicenter, randomized, open-label, phase II study. Patients with histologically proven invasive pancreatic ductal carcinoma, pathological stage I-III, and no local residual or microscopic residual tumor were eligible. Patients were randomized 1:1 to receive 6- or 12-month adjuvant chemotherapy with S-1. The primary endpoint was 2-year overall survival (OS). Secondary endpoints were disease-free survival (DFS) and feasibility. RESULTS: A total of 170 patients were randomized (85 per group); the full analysis set was 82 in both groups. Completion rates were 64.7% (6-month group) and 44.0% (12-month group). Two-year OS was 71.5% (6-month group) and 65.4% (12-month group) (hazard ratio (HR): 1.143; 80% confidence interval CI 0.841-1.553; P = 0.5758). Two-year DFS was 46.4% (6-month group) and 44.9% (12-month group) (HR: 1.069; 95% CI 0.727-1.572; P = 0.6448). In patients who completed the regimen, 2-year DFS was 56.5% (6-month group) and 75.0% (12-month group) (HR: 0.586; 95% CI 0.310-1.105; P = 0.0944). Frequent (≥ 5%) grade ≥ 3 adverse events comprised anorexia (10.5% in the 6-month group) and diarrhea (5.3% vs. 5.1%; 6- vs. 12-month group, respectively). CONCLUSIONS: In patients with resected pancreatic cancer, 12-month adjuvant chemotherapy with S-1 was not superior to 6-month therapy regarding OS and DFS.

Cancer-associated fibroblast senescence and its relation with tumour-infiltrating lymphocytes and PD-L1 expressions in intrahepatic cholangiocarcinoma.

BACKGROUND: Caveolin-1 (CAV1) in cancer-associated fibroblasts (CAFs) has pro- or anti-tumourigenic effect depending on the cancer type. However, its effect in intrahepatic carcinoma (ICC) remains unknown. Therefore, this study aimed to investigate the relationship between CAV1 in CAFs and tumour-infiltrating lymphocyte (TIL) numbers or PD-L1 levels in ICC patients. METHODS: Consecutive ICC patients (n = 158) were enrolled in this study. The levels of CAV1 in CAFs, CD8 + TILs, Foxp3+ TILs and PD-L1 in cancer cells were analysed using immunohistochemistry. Their association with the clinicopathological factors and prognosis were evaluated. The correlation between these factors was evaluated. RESULTS: CAV1 upregulation in CAFs was associated with a poor overall survival (OS) (P < 0.001) and recurrence-free survival (P = 0.008). Clinicopathological factors were associated with high CA19-9 levels (P < 0.001), advanced tumour stage (P = 0.046) and lymph node metastasis (P = 0.004). CAV1 level was positively correlated with Foxp3+ TIL numbers (P = 0.01). There were no significant correlations between CAV1 levels and CD8 + TIL numbers (P = 0.80) and PD-L1 levels (P = 0.97). An increased CD8 + TIL number and decreased Foxp3+ TIL number were associated with an increased OS. In multivariate analysis, positive CAV1 expression in CAFs (P = 0.013) and decreased CD8 + TIL numbers (P = 0.021) were independent poor prognostic factors. CONCLUSION: Cellular senescence, represented by CAV1 levels, may be a marker of CAFs and a prognostic indicator of ICC through Foxp3+ TIL regulation. CAV1 expression in CAFs can be a therapeutic target for ICC.

Neoadjuvant S-1 With Concurrent Radiotherapy Followed by Surgery for Borderline Resectable Pancreatic Cancer: A Phase II Open-label Multicenter Prospective Trial (JASPAC05).

OBJECTIVE: This study assessed whether neoadjuvant chemoradiotherapy (CRT) with S-1 increases the R0 resection rate in BRPC. SUMMARY OF BACKGROUND DATA: Although a multidisciplinary approach that includes neoadjuvant treatment has been shown to be a better strategy for BRPC than upfront resection, a standard treatment for BRPC has not been established. METHODS: A multicenter, single-arm, phase II study was performed. Patients who fulfilled the criteria for BRPC received S-1 (40 mg/m 2 bid) and concurrent radiotherapy (50.4 Gy in 28 fractions) before surgery. The primary endpoint was the R0 resection rate. At least 40 patients were required, with a 1-sided α = 0.05 and ß = 0.05 and expected and threshold values for the primary endpoint of 30% and 10%, respectively. RESULTS: Fifty-two patients were eligible, and 41 were confirmed to have definitive BRPC by a central review. CRT was completed in 50 (96%) patients and was well tolerated. The rate of grade 3/4 toxicity with CRT was 43%. The R0 resection rate was 52% among the 52 eligible patients and 63% among the 41 patients who were centrally confirmed to have BRPC. Postoperative grade III/IV adverse events according to the Clavien-Dindo classification were observed in 7.5%. Among the 41 centrally confirmed BRPC patients, the 2-year overall survival rate and median overall survival duration were 58% and 30.8 months, respectively. CONCLUSIONS: S-1 and concurrent radiotherapy seem to be feasible and effective at increasing the R0 resection rate and improving survival in patients with BRPC. TRIAL REGISTRATION: UMIN000009172.

Indications for conversion hepatectomy for initially unresectable colorectal cancer with liver metastasis.

PURPOSE: Selected patients with initially unresectable colorectal cancer (CRC) and liver metastases undergo conversion surgery after appropriate chemotherapy. The prognosis of these patients is good, with some even cured of the disease. This retrospective, single-institution study analyzes the clinical importance of patient characteristics on the outcomes of conversion hepatectomy. METHODS: We evaluated 229 consecutive patients with initially unresectable CRC and liver metastasis, who underwent systemic chemotherapy. The patients were assigned to groups depending on conversion hepatectomy. RESULTS: Conversion hepatectomy was performed in 30 patients (13.1%). The proportion of patients with extrahepatic metastasis was significantly lower in the conversion group than in the unresectable group (30.0 vs. 66.8%; P < 0.01). The rate of left-sided primary colorectal tumors was significantly higher in the conversion group than in the unresectable group (96.7 vs. 65.8%; P < 0.01). Multivariate analyses identified that left-sided tumors, no extrahepatic metastasis, H1 or H2 grade CLM, and treatment with molecular-targeted agents were associated with conversion hepatectomy (odds ratios: 16.314, 4.216, 7.631, and 4.070; P < 0.01). Overall survival was significantly longer in the conversion group than in the unresectable group (MST: 50.0 versus 14.7 months; P < 0.01). CONCLUSION: Left-sided primary tumors, absence of extrahepatic metastases, H1 or H2 grade, and use of molecular-targeted agents were associated with successful conversion hepatectomy; thus, patients with these characteristics may be candidates for conversion therapy.

Health-related quality of life after esophagectomy in patients with esophageal cancer.

Esophageal cancer is one of the malignant tumors with the poorest prognosis. Esophagectomy, which is the mainstay of curative-intent treatments, imposes excessive surgical stress on the patients, and postoperative morbidity and mortality rates after esophagectomy remain high. On the other hand, the number of survivors after esophagectomy for esophageal cancer is increasing due to recent improvements in surgical techniques and multidisciplinary treatments for this cancer. However, esophagectomy still has a great influence on the fundamental aspect of patients' lives, that is, the health-related quality of life (HR-QOL), including their physical, emotional, and social functions in the short- and long-term postoperatively. HR-QOL is a multifactorial concept used to assess the symptoms and functional changes caused by the disease itself and treatments from the patients' perspectives. Therefore, assessing the HR-QOL of patients with esophageal cancer after esophagectomy is becoming increasingly important. However, the status of HR-QOL changes after esophagectomy has not been satisfactorily evaluated, and there is no worldwide consensus as to how the postoperative HR-QOL can be improved. This review aimed to raise awareness of healthcare providers, such as surgeons and nurses, on the importance of HR-QOL in patients with esophageal cancer after curative-intent esophagectomy by providing multifaceted information concerning the short- and long-term HR-QOLs, including the status of changes and the determinants of HR-QOL after esophagectomy, and furthermore, essential points for improvement of HR-QOL after esophagectomy.

Prognostic significance of preoperative PNI and CA19-9 for pancreatic ductal adenocarcinoma: A multi-institutional retrospective study.

BACKGROUND: The aim of this study was to investigate the clinical value of nutritional and immunological prognostic scores as predictors of outcomes and to identify the most promising scoring system for patients with pancreatic ductal adenocarcinoma (PDAC) in a multi-institutional study. METHODS: Data were retrospectively collected for 589 patients who underwent surgical resection for PDAC. Prognostic analyses were performed for overall (OS) and recurrence-free survival (RFS) using tumor and patient-related factors, namely neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, Prognostic Nutritional Index (PNI), Glasgow Prognostic Score (GPS), modified GPS, C-reactive protein-to-albumin ratio, Controlling Nutritional Status score, and the Geriatric Nutritional Risk Index. RESULTS: Compared with PDAC patients with high PNI values (≥46), low PNI (<46) patients showed significantly worse overall survival (OS) (multivariate hazard ratio (HR), 1.432; 95% CI, 1.069-1.918; p = 0.0161) and RFS (multivariate HR, 1.339; 95% CI, 1.032-1.736; p = 0.0277). High carbohydrate antigen 19-9 (CA19-9) values (≥450) were significantly correlated with shorter OS (multivariate HR, 1.520; 95% CI, 1.261-2.080; p = 0.0002) and RFS (multivariate HR, 1.533; 95% CI, 1.199-1.961; p = 0.0007). Stratification according to PNI and CA19-9 was also significantly associated with OS and RFS (log rank, P < 0.0001). CONCLUSIONS: Our large cohort study showed that PNI and CA19-9 were associated with poor clinical outcomes in PDAC patients following surgical resection. Additionally, combining PNI with CA19-9 enabled further classification of patients according to their clinical outcomes.

Impact of a 7.5-Fr Pancreatic Stent for Preventing Pancreatic Fistula after Pancreaticoduodenectomy.

INTRODUCTION: Pancreatic duct stents are widely used to reduce the incidence of postoperative pancreatic fistula (POPF) after pancreaticoduodenectomy (PD); however, small stents may cause adverse effects, such as occlusion. Recently, we have tried placing a 7.5-Fr pancreatic duct stent to achieve more effective exocrine output from the pancreas; however, the association between pancreatic duct stent size and POPF remains unknown. METHODS: Sixty-five patients with soft pancreatic texture who underwent PD were retrospectively analyzed. After dividing the pancreas, a pancreatic duct stent (stent size 4.0 in 29 patients, 5.0 in 18, and 7.5 Fr in 18) was placed in the main pancreatic duct. RESULTS: Twenty-five of 65 patients with soft pancreatic texture (38.5%) developed POPF. POPF became less frequent as the pancreatic duct stent size increased (p = 0.003). The factors associated with POPF development were a 7.5-Fr pancreatic duct stent (p = 0.005), 5.0-Fr pancreatic duct stent (p = 0.031), and male sex (p = 0.008). Pancreatic duct stent size and pancreatic duct diameter did not differ between the POPF and non-POPF groups. DISCUSSION/CONCLUSIONS: In patients with a soft pancreas, the placement of a 7.5-Fr pancreatic duct stent may reduce the incidence of POPF.

Feasibility of hepatic resection for liver metastasis of head-and-neck carcinoma or esophageal carcinoma: a multi-center experience.

PURPOSE: Patients with liver metastasis of head-and-neck carcinoma and esophageal carcinoma are generally not treated with hepatic resection, but there are no established standard treatment methods. We report 11 cases of hepatic resection for liver metastasis of head-and-neck carcinoma or esophageal carcinoma performed at 5 Japanese institutions. METHODS: The subjects of this retrospective analysis were 11 patients who underwent hepatic resection for metastatic liver tumors, originating from head-and-neck carcinoma in 5 and from esophageal cancer in 6, between January, 2010 and March, 2020 RESULTS: There were nine men and two women (median age, 64 years; range 40-72 years). The primary disease was esophageal carcinoma in six patients and pharyngeal carcinoma in five patients. All cancers were squamous cell carcinoma. The time from the initial treatment to the diagnosis of liver metastasis was 15.3 months and the 1-year and 3-year overall survival rates after hepatic resection were 72% and 32%, respectively. The overall and disease-free survival rates after hepatic resection were significantly higher for patients who underwent hepatic resection more than 12 months after the initial treatment than for those who underwent hepatic resection within 12 months after the initial treatment (p = 0.0172 and p = 0.0120, respectively). CONCLUSIONS: Liver resection may prolong the survival of patients with liver metastases controlled for more than 12 months after the initial treatment of head and neck or esophageal carcinoma.

GTF2IRD1 on chromosome 7 is a novel oncogene regulating the tumor-suppressor gene TGFßR2 in colorectal cancer.

Chromosome 7q (Ch.7q) is clonally amplified in colorectal cancer (CRC). We aimed to identify oncogenes on Ch.7q that are overexpressed through DNA copy number amplification and determine the biological and clinical significance of these oncogenes in CRC. We identified general transcription factor 2I repeat domain-containing protein 1 (GTF2IRD1) as a potential oncogene using a CRC dataset from The Cancer Genome Atlas with a bioinformatics approach. We measured the expression of GTF2IRD1 in 98 patients with CRC using immunohistochemistry and RT-quantitative PCR (RT-qPCR). The biological effects of GTF2IRD1 expression were explored by gene set enrichment analysis (GSEA). Next, we undertook in vitro cell proliferation and cell cycle assays using siGTF2IRD1-transfected CRC cells. We further investigated the oncogenic mechanisms through which GTF2IRD1 promoted CRC progression. Finally, we assessed the clinical significance of GTF2IRD1 expression by RT-qPCR. GTF2IRD1 was overexpressed in tumor cells and liver metastatic lesions. The GSEA revealed a positive correlation between GTF2IRD1 expression and cell cycle progression-related genes. GTF2IRD1 knockdown inhibited cell proliferation and induced cell cycle arrest in Smad4-mutated CRC. GTF2IRD1 downregulated the expression of the gene encoding transforming growth factor ß receptor 2 (TGFßR2), a tumor-suppressor gene in Smad4-mutated CRC. On multivariate analysis, high GTF2IRD1 expression was an independent poor prognostic factor. Clinicopathological analysis showed that GTF2IRD1 expression was positively correlated with liver metastasis. In conclusion, GTF2IRD1 promoted CRC progression by downregulating TGFßR2 and could be a prognostic biomarker on Ch.7q in CRC. GTF2IRD1 could also be a novel oncogene in CRC.

Relationship between surgical R0 resectability and findings of peripancreatic vascular invasion on CT imaging after neoadjuvant S-1 and concurrent radiotherapy in patients with borderline resectable pancreatic cancer.

BACKGROUND: Borderline resectable pancreatic cancer (BRPC) is frequently associated with positive surgical margins and a poor prognosis because the tumor is in contact with major vessels. This study evaluated the relationship between the margin-negative (R0) resection rate and findings indicating peripancreatic vascular invasion on multidetector computed tomography (MDCT) imaging after neoadjuvant chemoradiotherapy (NACRT) in patients with BRPC. METHODS: Twenty-nine BRPC patients who underwent laparotomy after neoadjuvant S-1 with concurrent radiotherapy were studied retrospectively. Peripancreatic major vessel invasion was evaluated based on the length of tumor-vessel contact on MDCT. The R0 resection rates were compared between the progression of vascular invasion (PVI) group and the non-progression of vascular invasion (NVI) group. RESULTS: There were 3 patients with partial responses (10%), 25 with stable disease (86%), and 1 with progressive disease (3%) according to the RECISTv1.1 criteria. Regarding vascular invasion, 9 patients (31%) were classified as having PVI, and 20 patients (69%) were classified as having NVI. Of the 29 patients, 27 (93%) received an R0 resection, and all the PVI patients received an R0 resection (9/9; R0 resection rate = 100%) while 90% (18/20) of the NVI patients underwent an R0 resection. The exact 95% confidence interval of risk difference between those R0 resection rates was - 10.0% [- 31.7-20.4%]. CONCLUSIONS: Patients with BRPC after NACRT achieved high R0 resection rates regardless of the vascular invasion status. BRPC patients can undergo R0 resections unless progressive disease is observed after NACRT. TRIAL REGISTRATION: UMIN-CTR, UMIN000009172 . Registered 23 October 2012.

Mitochondrial expression of the DNA repair enzyme OGG1 improves the prognosis of pancreatic ductal adenocarcinoma.

BACKGROUND/OBJECTIVES: 8-Hydroxydeoxyguanosine (8-OHdG) is an indicator of oxidative stress and causes transversion mutations and carcinogenesis. 8-OHdG is excision repaired by 8-OHdG DNA glycosylase 1 (OGG1), which is classified as nuclear and mitochondrial subtypes. We aimed to clarify the role of OGG1 in pancreatic ductal adenocarcinoma (PDAC). METHODS: Ninety-two patients with PDAC who had undergone surgical resection at multiple institutions were immunohistochemically analyzed. The OGG1 and 8-OHdG expression levels were scored using the Germann Immunoreactive Score. The cutoff values of OGG1, as well as that of 8-OHdG, were determined. RESULTS: The low nuclear OGG1 expression group (n = 41) showed significantly higher carbohydrate antigen (CA)19-9 (p = 0.026), and higher s-pancreas antigen (SPAN)-1 (p = 0.017) than the high expression group (n = 51). Nuclear OGG1 expression has no effect on the prognosis. The low mitochondrial OGG1 expression group (n = 40) showed higher CA19-9 (p = 0.041), higher SPAN-1 (p = 0.032), and more histological perineural invasion (p = 0.037) than the high expression group (n = 52). The low mitochondrial OGG1 expression group had a significantly shorter recurrence-free survival (p = 0.0080) and overall survival (p = 0.0073) rates. The Cox proportional hazards model revealed that low mitochondrial OGG1 expression is an independent risk factor of the PDAC prognosis. OGG1 expression was negatively correlated with 8-OHdG expression (p = 0.0004), and high 8-OHdG expression shortened the recurrence-free survival of patients with PDAC. CONCLUSIONS: Low mitochondrial OGG1 expression might aggravate the PDAC prognosis.

Treatment strategies for neuroendocrine carcinoma of the upper digestive tract.

BACKGROUND: Neuroendocrine carcinoma (NEC) of the esophagus and the stomach is aggressive. The purpose of this study was to determine the optimal therapeutic strategy. METHODS: Both clinicopathological factors and treatment results were examined in 34 patients with immunohistochemically diagnosed NEC of the upper gastrointestinal tract (esophagus 22; stomach 12). RESULTS: Twenty-nine tumors showed protruding and localized type, like submucosal tumor. Esophagectomy and gastrectomy were performed in six and eight patients, respectively. Among the six patients with esophageal NEC, three with node metastasis developed recurrence within seven months, while the other three (pT1bN0) had no recurrence. Regarding gastric NEC, three patients with pT3N1 or 2 tumor received adjuvant chemotherapy and achieved a 5-year survival. However, the other five experienced recurrence after gastrectomy. Systemic chemotherapy was performed as the main treatment for 18 patients with advanced NEC. The median survival was 10 months after initial chemotherapy. No marked differences in the response were recognized between the 14 cases with esophageal NEC and the 4 with gastric NEC. The median survival was 14.3 and 5.3 months for the 11 effective and 7 non-effective patients, respectively. CONCLUSIONS: A macroscopically unique appearance, like submucosal tumor, suggests the possibility of NEC. Esophagectomy is an effective treatment option for limited-stage NEC without node metastasis, while gastrectomy followed by adjuvant chemotherapy may be effective for NEC even with node metastasis when R0 resection can be achieved. Systemic chemotherapy is relatively effective for advanced NEC, although early progression frequently develops.

Correction: Integrated Multiregional Analysis Proposing a New Model of Colorectal Cancer Evolution.

[This corrects the article DOI: 10.1371/journal.pgen.1005778.].

Laparoscopic spleen-preserving distal pancreatectomy for a solid-cystic intraabdominal desmoid tumor at a gastro-pancreatic lesion: a case report.

BACKGROUND: We report a case of an intraabdominal desmoid tumor that occurred at a gastro-pancreatic lesion with spontaneous cystic features, and present the successful laparoscopic resection of the tumor. CASE PRESENTATION: A 20-mm retroperitoneal cystic mass with a solid component was found adjacent to the stomach and pancreatic body in a 52-year-old woman with no history of familial adenomatous polyposis. Laparoscopic spleen-preserving distal pancreatectomy with wedge resection of the stomach was performed, and complete resection was achieved without intraoperative and postoperative complications. Histopathological examination by immunohistochemistry enabled diagnosis of a desmoid tumor that had originated from the stomach and invaded the pancreatic parenchyma with a spontaneous cystic change. We herein report an extremely rare case of an intraabdominal desmoid tumor with a spontaneous cystic change. CONCLUSION: Regardless of its rarity, desmoid tumor should be included in the preoperative differential diagnosis of a cystic intraabdominal mass, and laparoscopic function-preserving surgery may be an optimal treatment option.

The evolution of surgical treatment for gastrointestinal cancers.

INTRODUCTION: According to the latest Japanese nationwide estimates, over a million Japanese people are newly diagnosed with cancer each year. Since gastrointestinal cancers account for more than 40% of all cancer-related deaths, it is imperative to formulate effective strategies to control them. MATERIALS AND METHODS, AND RESULTS: Basic drug discovery research Our research has revealed that the abnormal expression of regulators of chromosomal stability is a cause of cancers and identified an effective compound against cancers with chromosomal instability. We revealed the molecular mechanism of peritoneal dissemination of cancer cells via the CXCR4/CXCL12 axis to CAR-like cells and identified an MEK inhibitor effective against these tumors. Residual tumor cells after chemotherapy in colorectal cancer are LGR5-positive cancer stem cells and their ability to eliminate reactive oxygen species is elevated. The development of surgical procedures and devices In cases of gastric tube reconstruction for esophageal cancer, we determined the anastomotic line for evaluating the blood flow using ICG angiography and measuring the tissue O2 metabolism. We established a novel gastric reconstruction method (book-binding technique) for gastric cancer and a new rectal reconstruction method focusing on the intra-intestinal pressure resistance for rectal cancer. We established a novel tissue fusion method, which allows contact-free local heating and retains tissue viability with very little damage, and developed an understanding of the collagen-related processes that underpin laser-induced tissue fusion. Strategy to prevent carcinogenesis We succeeded in cleaving hepatitis B virus DNA integrated into the nucleus of hepatocytes using genome editing tools. The development of HCC from non-alcoholic steatohepatitis (NASH) may be prevented by metabolic surgery. CONCLUSION: We believe that these efforts will help to significantly improve the gastrointestinal cancer treatment and survival.

Significance of bile culture surveillance for postoperative management of pancreatoduodenectomy.

BACKGROUND: The management of infectious complications is important in pancreatoduodenectomy (PD). We sought to determine the significance of preoperative surveillance bile culture in perioperative management of PD. METHODS: This study enrolled 69 patients who underwent PD for malignant tumors at a single institute between 2014 and 2017. Surveillance bile culture was performed before or during surgery. Correlations between the incidence of infectious postoperative complications and clinicopathological parameters, including bile cultures, were evaluated. RESULTS: Preoperative positive bile culture was confirmed in 28 of 51 patients (55%). Bile culture was positive in 27 of 30 cases (90%) with preoperative biliary drainage, and 1 of 21 cases (5%) without drainage (p < 0.01). Preoperative isolated microorganisms in bile were consistent with those detected in surgical sites in 11 of 27 cases (41%). Cases with positive multi-drug-resistant bacteria in preoperative bile culture showed significantly higher incisional SSI after PD (p = 0.01). The risk factors for the incidence of organ/space SSI were soft pancreatic texture (p = 0.01) and smoking history (p = 0.02) by multivariate analysis. Preoperative positive bile culture was neither associated with organ/space SSI nor overall postoperative complications. CONCLUSIONS: Preoperative surveillance bile culture is useful for the management of wound infection, prediction of causative pathogens for infectious complications, and the selection of perioperative antibiotic prophylaxis.

Dysregulated YAP1/TAZ and TGF-ß signaling mediate hepatocarcinogenesis in Mob1a/1b-deficient mice.

Mps One Binder Kinase Activator (MOB)1A/1B are core components of the Hippo pathway that coactivate large tumor suppressor homolog (LATS) kinases. Mob1a/1b double deficiency in mouse liver (LMob1DKO) results in hyperplasia of oval cells and immature cholangiocytes accompanied by inflammatory cell infiltration and fibrosis. More than half of mutant mice die within 3 wk of birth. All survivors eventually develop liver cancers, particularly combined hepatocellular and cholangiocarcinomas (cHC-CCs) and intrahepatic cholangiocellular carcinomas (ICCs), and die by age 60 wk. Because this phenotype is the most severe among mutant mice lacking a Hippo signaling component, MOB1A/1B constitute the critical hub of Hippo signaling in mammalian liver. LMob1DKO liver cells show hyperproliferation, increased cell saturation density, hepatocyte dedifferentiation, enhanced epithelial-mesenchymal transition and cell migration, and elevated transforming growth factor beta(TGF-ß)2/3 production. These changes are strongly dependent on Yes-Associated Protein-1 (Yap1) and partially dependent on PDZ-binding motif (Taz) and Tgfbr2, but independent of connective tissue growth factor (Ctgf). In human liver cancers, YAP1 activation is frequent in cHC-CCs and ICCs and correlates with SMAD family member 2 activation. Drug screening revealed that antiparasitic macrocyclic lactones inhibit YAP1 activation in vitro and in vivo. Targeting YAP1/TAZ with these drugs in combination with inhibition of the TGF-ß pathway may be effective treatment for cHC-CCs and ICCs.

Integrated Multiregional Analysis Proposing a New Model of Colorectal Cancer Evolution.

Understanding intratumor heterogeneity is clinically important because it could cause therapeutic failure by fostering evolutionary adaptation. To this end, we profiled the genome and epigenome in multiple regions within each of nine colorectal tumors. Extensive intertumor heterogeneity is observed, from which we inferred the evolutionary history of the tumors. First, clonally shared alterations appeared, in which C>T transitions at CpG site and CpG island hypermethylation were relatively enriched. Correlation between mutation counts and patients' ages suggests that the early-acquired alterations resulted from aging. In the late phase, a parental clone was branched into numerous subclones. Known driver alterations were observed frequently in the early-acquired alterations, but rarely in the late-acquired alterations. Consistently, our computational simulation of the branching evolution suggests that extensive intratumor heterogeneity could be generated by neutral evolution. Collectively, we propose a new model of colorectal cancer evolution, which is useful for understanding and confronting this heterogeneous disease.