Presence of Fusobacterium nucleatum in relation to patient survival and an acidic environment in oesophagogastric junction and gastric cancers.

BACKGROUND: Fusobacterium nucleatum inhabits the oral cavity and affects the progression of gastrointestinal cancer. Our prior findings link F. nucleatum to poor prognosis in oesophageal squamous cell carcinoma via NF-κB pathway. However, its role in oesophagogastric junction and gastric adenocarcinoma remains unexplored. We investigated whether F. nucleatum influences these cancers, highlighting its potential impact. METHODS: Two cohorts of EGJ and gastric adenocarcinoma patients (438 from Japan, 380 from the USA) were studied. F. nucleatum presence was confirmed by qPCR, FISH, and staining. Patient overall survival (OS) was assessed based on F. nucleatum positivity. EGJ and gastric adenocarcinoma cell lines were exposed to F. nucleatum to study molecular and phenotypic effects, validated in xenograft mouse model. RESULTS: In both cohorts, F. nucleatum-positive EGJ or gastric adenocarcinoma patients had notably shorter OS. F. nucleatum positivity decreased in more acidic tumour environments. Cancer cell lines with F. nucleatum showed enhanced proliferation and NF-κB activation. The xenograft model indicated increased tumour growth and NF-κB activation in F. nucleatum-treated cells. Interestingly, co-occurrence of F. nucleatum and Helicobacter pylori, a known risk factor, was rare. CONCLUSIONS: F. nucleatum can induce the NF-κB pathway in EGJ and gastric adenocarcinomas, leading to tumour progression and poor prognosis.

Body Composition and Clinical Outcomes in Esophageal Cancer Patients Treated with Immune Checkpoint Inhibitors.

BACKGROUND: Obesity is associated with increased mortality in various cancers, but the relationship between obesity and clinical outcomes in unresectable or recurrent esophageal cancer who receive immune checkpoint inhibitors (ICIs) remains unknown. This study investigated the association between body composition and clinical outcomes in patients with unresectable or recurrent esophageal cancer who received ICIs. METHODS: Utilizing an unbiased database of 111 unresectable or recurrent esophageal cancers, we evaluated the relationships between body composition (body mass index, waist circumference, psoas major muscle volume, and subcutaneous and visceral fat areas) at the initiation of ICI treatment and clinical outcomes including the disease control rate and progression-free survival (PFS). RESULTS: Waist circumference was significantly associated with the disease control rate at the first assessment (P = 0.0008). A high waist circumference was significantly associated with favorable PFS in patients treated with nivolumab. In an univariable model, for 5-cm increase of waist circumference in the outcome category of PFS, univariable hazard ratio (HR) was 0.73 (95% confidence interval [CI], 0.61-0.87; P = 0.0002). A multivariable model controlling for potential confounders yielded a similar finding (multivariable HR, 0.56; 95% CI, 0.33-0.94; P = 0.027). We observed the similar finding in esophageal cancer patients treated with pembrolizumab+CDDP+5-FU (P = 0.048). In addition, waist circumference was significantly associated with the prognostic nutritional index (P = 0.0073). CONCLUSIONS: A high waist circumference was associated with favorable clinical outcomes in ICI-treated patients with unresectable or recurrent esophageal cancer, providing a platform for further investigations on the relationships among body composition, nutrition, and the immune status.

Intratumour Fusobacterium nucleatum and immune response to oesophageal cancer.

BACKGROUND: Experimental evidence suggests a role of intratumour Fusobacterium nucleatum in the aggressive behaviour of gastrointestinal cancer through downregulating anti-tumour immunity. We investigated the relationship between intratumour F. nucleatum and immune response to oesophageal cancer. METHODS: Utilising an unbiased database of 300 resected oesophageal cancers, we measured F. nucleatum DNA in tumour tissue using a quantitative polymerase chain reaction assay, and evaluated the relationship between the abundance of F. nucleatum and the densities of T cells (CD8 + , FOXP3 + and PDCD1 + ), as well as lymphocytic reaction patterns (follicle lymphocytic reaction, peritumoural lymphocytic reaction, stromal lymphocytic reaction and tumour-infiltrating lymphocytes) in oesophageal carcinoma tissue. RESULTS: F. nucleatum was significantly and inversely associated only with the peritumoural lymphocytic reaction (P = 0.0002). Compared with the F. nucleatum-absent group, the F. nucleatum-high group showed a much lower level of the peritumoural lymphocytic reaction (univariable odds ratio, 0.33; 95% confidence interval, 0.16-0.65; P = 0.0004). A multivariable model yielded a similar finding (multivariable odds ratio, 0.34; 95% confidence interval 0.16-0.69; P = 0.002). CONCLUSIONS: Intratumour F. nucleatum is associated with a diminished peritumoural lymphocytic reaction, providing a platform for further investigations on the potential interactive roles between intratumour F. nucleatum and host immunity.

Frailty Assessed by the Clinical Frailty Scale is Associated with Prognosis After Esophagectomy.

BACKGROUND: The Clinical Frailty Scale (CFS) is a simple and validated tool for assessing frailty, and higher CFS scores are correlated with worse perioperative outcomes after cardiovascular surgery. However, the relationship between the CFS scores and postoperative outcomes after esophagectomy remain unclear. METHODS: We retrospectively analyzed data from 561 patients with esophageal cancer (EC) who underwent resection from August 2010 to August 2020. We defined a CFS score of ≥4 as indicative of frailty; thus, patients were classified into frail patients (CFS scores of ≥4) and non-frail patients (CFS scores of ≤3). The Kaplan-Meier method was used to describe the overall survival (OS) distributions with the log-rank test. RESULTS: Of the 561 patients, 90 (16%) had frailty and 471 (84%) did not. Frail patients had a significantly older age, lower body mass index, higher American Society of Anesthesiologists physical status classification, and greater cancer progression than non-frail patients. The 5-year survival rate was 68% in non-frail patients and 52% in frail patients. OS was significantly shorter in frail than non-frail patients (p = 0.017 by log-rank test). In particular, OS was significantly shorter in frail patients with clinical stage I-II EC (p = 0.0024 by log-rank test) but was not correlated with frailty in patients with clinical stage III-IV EC (p = 0.87 by log-rank test). CONCLUSIONS: Preoperative frailty was associated with shorter OS after resection of EC. The CFS score may be a prognostic biomarker for patients with EC, especially early-stage EC.

C-Reactive Protein Levels After Esophagectomy are Associated with Increased Surgical Complications and Poor Prognosis in Esophageal Squamous Cell Carcinoma Patients.

BACKGROUND: C-reactive protein (CRP) levels are reported to predict complications and survival after surgery in various cancers. However, the relationship between postoperative CRP levels and short- and long-term outcomes of esophageal squamous cell carcinoma (ESCC) patients after esophagectomy is unclear. METHOD: We reviewed the records of 543 ESCC patients who underwent subtotal esophagectomy with gastric conduit reconstruction at Kumamoto University Hospital between August 2010 and July 2021. Blood tests for CRP were done on postoperative days (PODs) 1, 3, 5 or 6, and 7 or 8. RESULTS: The mean CRP levels on day 1, day 3, day 5/6, and day 7/8 were 6.68 ± 0.13 mg/dL, 11.49 ± 0.27 mg/dL, 7.48 ± 0.26 mg/dL, and 5.38 ± 0.22 mg/dL, respectively. Mean CRP levels were highest on day 3, and CRP levels after day 3 correlated with grade >2 complications based on the Clavien-Dindo classification. Receiver operating characteristic curve analysis established the optimal cut-off value for CRP day 3 levels to be 12.19 mg/dL. Multivariate logistic regression analyses found that high CRP day 3 levels significantly correlated with grade >2 complications (odds ratio [OR] 3.77, 95% confidence interval [CI] 2.56-5.35; p < 0.001). Moreover, high day 7/8 CRP levels (>3.52) correlated with postoperative survival, and based on multivariate logistic regression analyses, were significantly associated with poor prognosis (hazard ratio 1.67, 95% CI 1.14-2.43; p = 0.008). CONCLUSION: Our findings suggest CRP day 3 levels as a potential biomarker for predicting postoperative complications and that CRP day 7/8 levels have potential prognostic value for ESCC patients after esophagectomy.

Dynamic Alteration in HLA-E Expression and Soluble HLA-E via Interaction with Natural Killer Cells in Gastric Cancer.

BACKGROUND: Some reports showed the immune tolerance of soluble human leukocyte antigen E (HLA-E), but the role that soluble HLA-E plays in gastric cancer (GC) is unknown. We aimed to clarify the molecular mechanism and clinical significance of soluble HLA-E in GC. METHODS: We examined the expression of HLA-E on GC cells and soluble HLA-E under co-culture with natural killer (NK) cells in a time-dependent manner. Changes in NK cell activity were investigated using anti-NK group 2 member A (NKG2A) antibodies in the presence of soluble HLA-E. Expression of soluble HLA-E in the serum of GC patients was determined. RESULTS: Whereas HLA-E expression on GC cells peaked with interferon (IFN)-γ secretion by NK cells in a time-dependent manner, soluble HLA-E was upregulated in conditioned medium. Pre-incubation with anti-NKG2A antibodies increased the activation of NKG2A+ NK cells in the presence of soluble HLA-E. Expression of soluble HLA-E in the serum of GC patients correlated with disease progression. CONCLUSIONS: HLA-E expression dynamically changes on GC cells and in conditioned medium. Furthermore, soluble HLA-E can contribute to immune escape in GC cell lines, which may have significance in clinical practice. Moreover, soluble HLA-E may be a potential prognostic biomarker.

Localized Gastroesophageal Adenocarcinoma in the Elderly: Is Age a Factor Associated with Suboptimal Treatment?

INTRODUCTION: Gastroesophageal adenocarcinoma is relatively common in elderly patients as the incidence increases with age. However, the optimal treatment approach is not well established in this group of patients. The aim of this study is to review our experience for localized gastroesophageal adenocarcinoma in patients aged ≥80 years and to assess association between patient characteristics, clinical factors, and overall survival (OS) in order to optimize the therapeutic approaches for this population. METHODS: Patients ≥80 years old treated for localized gastroesophageal adenocarcinoma were retrospectively analyzed. Survival curves were estimated using the Kaplan-Meier method. Univariate and multivariate Cox proportional hazards regression models were applied to assess the association between patient characteristics and OS. Factors that were significant in the multivariate model were included in the final reduced model. RESULTS: 127 patients ≥80 years old, were included in this study with median age of 83 years. The median follow-up time was 3.2 years, and median OS was 2.5 years (95% CI: 2.0-3.1 years). Independent prognostic factors for OS were Eastern Cooperative Oncology Group (ECOG) performance status (PS) (p = 0.003), baseline clinical stage (p = 0.01), and surgery (p = 0.001). ECOG PS, tumor location, baseline stage, tumor grade, and surgery were included in the final reduced model. CONCLUSION: Surgical treatment can improve survival in elderly patients. Therapeutic decisions should be based on the patients' general condition rather that age alone.

Postoperative respiratory morbidity can adversely affect prognosis in thoracoscopic esophagectomy for esophageal cancer: a retrospective study.

BACKGROUND: Esophagectomy for esophageal cancer is associated with frequent respiratory morbidities, which may deteriorate postoperative survival outcomes. Thoracoscopic esophagectomy (TE) is less invasive and is associated with fewer respiratory morbidities than open esophagectomy. However, the relationship between post-TE respiratory morbidity and prognosis has not been well established. METHODS: This study included 378 patients who underwent TE for esophageal cancer between May 2011 and November 2020. Patients were divided into two groups based on the presence of respiratory morbidity. Short-term and long-term outcomes of the groups were retrospectively compared. RESULTS: Respiratory morbidity was significantly associated with heavy past smoking habits (Brinkman index, p = 0.0039), short duration of smoking cessation (p = 0.0012), worse American Society of Anesthesiologists physical status (p = 0.016), frequent cardiovascular comorbidities (p = 0.0085), and long hospital stay (p < 0.001). Respiratory morbidity significantly deteriorated overall survival (OS) (p = 0.011) and relapse-free survival (p = 0.062) and could be an independent prognostic factor for OS (hazard ratio = 1.90, 95% confidence interval = 1.093-3.311, p = 0.023) along with clinical stage. CONCLUSION: Respiratory morbidity can adversely affect prognosis after TE. Various prophylaxes for respiratory morbidity are required to improve the short-term and long-term outcomes of TE for esophageal cancer.

Evaluation of HLA-E Expression Combined with Natural Killer Cell Status as a Prognostic Factor for Advanced Gastric Cancer.

BACKGROUND: The NKG2A/HLA-E pathway functions as an immune checkpoint with potential for inhibition using therapeutic antibodies. Through this pathway, immune cells lose activity, which allows cancers to progress. We aimed to determine whether HLA-E expression combined with NK cell status serves as a prognostic biomarker for gastric cancer (GC). METHODS: We enrolled patients (n = 232) with advanced GC who underwent curative gastrectomy. Immunohistochemical analyses of global HLA-E expression, and the expression of CD56 and CD3 to identify NK cells were performed. Survival analysis was performed to evaluate the significance of HLA-E expression and NK status. RESULTS: Patients with HLA-E-positive was 104 (41.3%) and had significantly worse prognosis of relapse-free survival (RFS) compared with those with HLA-E-negative. Moreover, patients with NK Low status had worse prognoses for RFS compared with those with NK High status. Statistical analysis of RFS demonstrated that HLA-E expression was a significant independent factor for poor prognosis (HR 1.57, 95% CI 1.04-2.36, P = 0.031). Furthermore, HLA-E-positive patients with low NK low status experienced the shortest RFS, particularly those in the upper GC group. CONCLUSIONS: HLA-E served as a prognostic factor after curative resection of GC, and HLA-E expression combined with NK status served as a sensitive prognostic biomarker for advanced GC.

Clinical Significance of Pretreatment Red Blood Cell Distribution Width as a Predictive Marker for Postoperative Morbidity After Esophagectomy for Esophageal Cancer: A Retrospective Study.

BACKGROUND: Clinical significance of red blood cell distribution (RDW) as a predictive marker for the incidence of postoperative morbidity after esophagectomy for esophageal cancer has not been established. METHODS: This study included 634 consecutive patients who underwent three-incisional esophagectomy with lymphadenectomy for esophageal cancer between April 2005 and November 2020. Correlation between pretreatment RDW and patient background, cancer background, and short-term outcome after esophagectomy were retrospectively investigated. RESULTS: Eighty patients (12.6%) had a high pretreatment RDW (> 14.2), which correlated with malnutrition estimated by body mass index, hemoglobin, total lymphocyte count, albumin, and total cholesterol. High pretreatment RDW was an independent risk factor for postoperative severe morbidity of grade IIIb or higher based on the Clavien-Dindo classification (hazard ratio [HR] 3.90, 95% confidence interval [CI] 1.707-8.887; p = 0.0012) and reoperation (HR 4.39, 95% CI 1.552-12.390; p = 0.0053) after open esophagectomy (OE). However, RDW was not associated with postoperative morbidity incidence after minimally invasive esophagectomy (MIE). CONCLUSIONS: Pretreatment RDW may be a surrogate marker for nutritional status and could be a predictive marker for postoperative severe morbidity, reoperation, and possibly pneumonia after OE. On the contrary, the lower invasiveness of MIE may have reduced the effect of pretreatment malnutrition on morbidity incidence, which could explain the insignificant relationship between RDW and poor short-term outcomes in MIE.

Preoperative Smoking Cessation and Prognosis After Curative Esophagectomy for Esophageal Cancer: A Cross-Sectional Study.

BACKGROUND: Several cohort studies have reported that post-esophagectomy morbidities may worsen prognosis. Smoking cessation is an effective prophylactic measure for reducing post-esophagectomy morbidity; however, whether smoking cessation can contribute to the improvement of prognosis is unknown due to the absence of reliable databases covering the cessation period. This study aimed to elucidate whether sufficient preoperative smoking cessation can improve prognosis after esophageal cancer surgery by reducing post-esophagectomy morbidity. METHODS: This study included 544 consecutive patients who underwent curative McKeown and Ivor-Lewis esophagectomies for esophageal cancer between May 2011 and June 2021. Data on smoking status and cessation period were prospectively accumulated. Survival data were finally updated on 30 January 2022. Receiver operating characteristic curve analysis for the cut-off value of appropriate cessation period in reducing post-esophagectomy respiratory morbidity as well as analyses for the association of cessation period with short- and long-term outcomes were performed. RESULTS: Post-esophagectomy morbidity significantly diminished overall survival (OS) after esophagectomy (p = 0.0003). A short preoperative smoking cessation period of ≤ 2 months was associated with frequent post-esophagectomy morbidity of Clavien-Dindo classification ≥IIIb (p = 0.0059), pneumonia (p = 0.016), respiratory morbidity (p = 0.0057), and poor OS in clinical stages II and III (p = 0.0015). Moreover, it was an independent factor for poor OS (hazard ratio 1.85, 95% confidence interval 1.068-3.197; p = 0.028), along with body mass index <18.5 and R1 resection. CONCLUSIONS: Sufficient preoperative smoking cessation > 2 months may be effective in improving not only short-term outcomes but also prognosis after esophagectomy for locally advanced esophageal cancer.

Impact of Type of Gastrectomy on Death from Pneumonia in Elderly Patients with Gastric Cancer Over the Long Term.

BACKGROUND: Gastrectomy may induce significant postoperative disabilities and worsen the quality of life in elderly patients. Without a functioning esophagogastric junction (EGJ), swallowing is impaired because of the anatomical and physiological changes after surgery, which increases the risk of postoperative pneumonia. The aim of this study was to identify the impact of the type of surgical procedure on death from pneumonia in elderly patients with gastric cancer (GC) over the long term. METHODS: We analyzed the data of 343 patients with GC who underwent curative gastrectomy in our hospital. We divided the patients into elderly and non-elderly groups. Among them, 109 patients aged ≥ 75 years who underwent curative resection were analyzed, their clinicopathological factors and clinical outcomes were compared, and the impact of the type of surgical procedure on death from pneumonia over the long term was evaluated. The institutional scientific review board of Kumamoto University Hospital was approved for data collection and analysis (No. 1037). RESULTS: There were significantly higher levels of American Society of Anesthesiologists (ASA) and poor nutrition in the elderly group; however, gender, BMI and factors related to pneumonia did not differ significantly between groups. The median duration of follow-up time 1588 days. On the multivariate analysis, age and surgical procedure were selected as independent predictive factors for pneumonia-related survival. CONCLUSION: Preservation of the EGJ as much as possible while maintaining curability is useful for reducing postoperative death from pneumonia over the long term in elderly patients with gastric cancer.

A retrospective study of preoperative malnutrition based on the Controlling Nutritional Status score as an associated marker for short-term outcomes after open and minimally invasive esophagectomy for esophageal cancer.

PURPOSE: Preoperative malnutrition is a significant risk factor for post-esophagectomy morbidity. The Controlling Nutritional Status (CONUT) is an index used to assess nutritional status, and it has been suggested to predict post-esophagectomy morbidity. However, the difference in the predictive value of CONUT in estimating morbidities between open esophagectomy (OE) and minimally invasive esophagectomy (MIE) has not yet been elucidated. METHODS: This study included patients who underwent a three-incision esophagectomy for esophageal cancer between April 2005 and August 2021. The patients were further divided into two groups according to their preoperative CONUT scores: normal and light malnutrition and moderate and severe malnutrition. Short-term outcomes between these groups were retrospectively compared in the OE and MIE groups. RESULTS: A total of 674 patients who underwent OE (296) and MIE (378) were analyzed. Moreover, 32 patients of the OE group and 16 of the MIE group were classified as having moderate and severe malnutrition, respectively. Moderate and severe malnutrition was significantly associated with a low body mass index, poor performance status, poor American Society of Anesthesiologists physical status, advanced cancer stage, and frequent preoperative treatment. These patients also experienced significantly more frequent morbidities of grade ≥ IIIb according to the Clavien-Dindo classification (CDc), respiratory, and cardiovascular morbidities after OE. Moreover, moderate and severe malnutrition in CONUT was an independent risk factor for morbidity of CDc ≥ IIIb (odds ratio [OR] vs. normal and light malnutrition = 3.38; 95% confidence interval [CI], 1.225-9.332; p = 0.019), respiratory (OR = 3.00; 95% CI, 1.161-7.736; p = 0.023), and cardiovascular morbidities (OR = 3.66; 95% CI, 1.068-12.55; p = 0.039) after OE. Meanwhile, moderate and severe malnutrition in CONUT did not increase the incidence of postoperative morbidities after MIE. CONCLUSION: Preoperative malnutrition in CONUT reflects various disadvantageous clinical factors and could be a predictor of worse short-term outcomes after OE, but it has no value in MIE. The low invasiveness of MIE might reduce the effect of preoperative malnutrition on worse short-term outcomes.

Minimally invasive esophagectomy may contribute to low incidence of postoperative surgical site infection in patients with poor glycemic control.

PURPOSE: High preoperative hemoglobin A1c (HbA1c) levels have been suggested to increase complications after esophagectomy. Minimally invasive esophagectomy (MIE) is less invasive than open esophagectomy (OE) and may reduce postoperative complications. However, it has not been established whether MIE contributes to low morbidity in patients with high preoperative HbA1c levels. Thus, the current study aimed to elucidate the effect of preoperative HbA1c levels on the incidence of complications each after OE and MIE. METHODS: A total of 280 patients who underwent OE and 304 patients who underwent MIE for esophageal cancer between April 2005 and April 2020 were retrospectively analyzed. The OE and MIE groups were further divided into two groups according to their preoperative HbA1c levels (< 6.9%, ≥ 6.9%). RESULTS: Patients with high HbA1c levels had a significantly higher incidence of surgical site infections (SSIs) after OE (P = 0.0048). Multivariate analysis demonstrated that a high HbA1c level was an independent risk factor for frequent SSIs after OE (hazard ratio 2.52; 95% confidence interval, 1.101- 5.739; P = 0.029). On the contrary, a high HbA1c level did not affect the incidence of SSI after MIE (P = 1.00). A high HbA1c level was not associated with the incidence of morbidities other than SSI after OE and MIE. CONCLUSIONS: A high preoperative HbA1c level significantly increased SSI risk after OE but not after MIE. It was suggested that lower invasiveness of MIE could contribute to a low incidence of SSI, even in patients with poor preoperative glycemic control.

Preoperative transferrin level is a novel indicator of short- and long-term outcomes after esophageal cancer surgery.

BACKGROUND: This study aimed to examine whether preoperative serum transferrin, a rapid-turnover protein, correlates with short- and long-term outcomes after esophagectomy. METHODS: Preoperative transferrin levels, calculated by summing serum iron and unsaturated iron-binding capacity, were evaluated in 224 patients who underwent esophagectomy for stage I-III esophageal cancer without preoperative treatment. Transferrin levels are directly proportional to total iron-binding capacity (TIBC), and we defined TIBC < 250 µg/dL as low transferrin. We evaluated the relationship between preoperative transferrin levels and short- and long-term outcomes after esophagectomy using univariate and multivariate Cox proportional hazards analyses. RESULTS: Of all patients, 25 (11.2%) had low preoperative transferrin levels. Low preoperative transferrin levels were strongly correlated with worse preoperative performance status, advanced pathological T stage, and more open esophagectomy (p = 0.0078, 0.0001, and 0.013, respectively). Patients with low preoperative transferrin levels experienced significantly more frequent postoperative pneumonia in univariate and multivariate analysis [hazard ratio (HR) 3.30, 95% confidence interval (CI) 1.032-10.033, p = 0.0443]. Additionally, these patients were significantly correlated with worse overall survival (OS) in univariate and multivariate analyses (HR 2.75, 95% CI 1.018-7.426, p = 0.0460). Furthermore, we investigated the relationship between OS and postoperative pneumonia to elucidate why low preoperative transferrin, which is an independent risk factor for postoperative pneumonia, leads to poor prognosis. Patients with postoperative pneumonia were strongly associated with a shorter OS (p = 0.0099). CONCLUSION: Preoperative serum transferrin levels may be a novel indicator of postoperative pneumonia and OS after esophagectomy.

YAP1 mediates gastric adenocarcinoma peritoneal metastases that are attenuated by YAP1 inhibition.

OBJECTIVE: Peritoneal carcinomatosis (PC; malignant ascites or implants) occurs in approximately 45% of advanced gastric adenocarcinoma (GAC) patients and associated with a poor survival. The molecular events leading to PC are unknown. The yes-associated protein 1 (YAP1) oncogene has emerged in many tumour types, but its clinical significance in PC is unclear. Here, we investigated the role of YAP1 in PC and its potential as a therapeutic target. METHODS: Patient-derived PC cells, patient-derived xenograft (PDX) and patient-derived orthotopic (PDO) models were used to study the function of YAP1 in vitro and in vivo. Immunofluorescence and immunohistochemical staining, RNA sequencing (RNA-Seq) and single-cell RNA-Seq (sc-RNA-Seq) were used to elucidate the expression of YAP1 and PC cell heterogeneity. LentiCRISPR/Cas9 knockout of YAP1 and a YAP1 inhibitor were used to dissect its role in PC metastases. RESULTS: YAP1 was highly upregulated in PC tumour cells, conferred cancer stem cell (CSC) properties and appeared to be a metastatic driver. Dual staining of YAP1/EpCAM and sc-RNA-Seq revealed that PC tumour cells were highly heterogeneous, YAP1high PC cells had CSC-like properties and easily formed PDX/PDO tumours but also formed PC in mice, while genetic knockout YAP1 significantly slowed tumour growth and eliminated PC in PDO model. Additionally, pharmacologic inhibition of YAP1 specifically reduced CSC-like properties and suppressed tumour growth in YAP1high PC cells especially in combination with cytotoxics in vivo PDX model. CONCLUSIONS: YAP1 is essential for PC that is attenuated by YAP1 inhibition. Our data provide a strong rationale to target YAP1 in clinic for GAC patients with PC.

Integrated genomic profiling and modelling for risk stratification in patients with advanced oesophagogastric adenocarcinoma.

OBJECTIVE: Prognosis of patients with advanced oesophagogastric adenocarcinoma (mEGAC) is poor and molecular determinants of shorter or longer overall survivors are lacking. Our objective was to identify molecular features and develop a prognostic model by profiling the genomic features of patients with mEGAC with widely varying outcomes. DESIGN: We profiled 40 untreated mEGACs (20 shorter survivors <13 months and 20 longer survivors >36 months) with whole-exome sequencing (WES) and RNA sequencing and performed an integrated analysis of exome, transcriptome, immune profile and pathological phenotypes to identify the molecular determinants, developing an integrated model for prognosis and comparison with The Cancer Genome Atlas (TCGA) cohorts. RESULTS: KMT2C alterations were exclusively observed in shorter survivors together with high level of intratumour heterogeneity and complex clonal architectures, whereas the APOBEC mutational signatures were significantly enriched in longer survivors. Notably, the loss of heterozygosity in chromosome 4 (Chr4) was associated with shorter survival and 'cold' immune phenotype characterised by decreased B, CD8, natural killer cells and interferon-gamma responses. Unsupervised transcriptomic clustering revealed a shorter survivor subtype with distinct expression features (eg, upregulated druggable targets JAK2, MAP3K13 and MECOM). An integrated model was then built based on clinical variables and the identified molecular determinants, which significantly segregated shorter and longer survivors. All the above features and the integrated model have been validated independently in multiple TCGA cohorts. CONCLUSION: This study discovered novel molecular features prognosticating overall survival in patients with mEGAC and identified potential novel targets in shorter survivors.

Trastuzumab upregulates programmed death ligand-1 expression through interaction with NK cells in gastric cancer.

BACKGROUND: The predictive significance of programmed death ligand 1 (PD-L1) for programmed death 1 (PD-1) inhibitors remains unclear in gastric cancer (GC) due to the dynamic alteration by treatments. We aimed to elucidate the effects of trastuzumab (Tmab) on PD-L1 expression in GC. METHODS: PD-L1 expression was evaluated by multicolour flow cytometry analysis after co-culturing GG cell lines and immune cells with Tmab. IFN-γ in the co-culture experiments was quantified. Immunohistochemistry (IHC) for PD-L1 expression using clinical samples was also performed to confirm PD-L1 alteration by Tmab. RESULTS: PD-L1 expression was significantly upregulated by Tmab in HER2-amplified GC cell lines co-cultured with peripheral blood mononuclear cells (PBMCs). PD-L1 upregulation by Tmab was also observed in the GC cells co-cultured with NK cells in time-dependent manner, but not with monocytes. IFN-γ concentration in conditioned media from co-cultured PBMCs and NK cells with Tmab was significantly higher and anti-IFN-γ significantly suppress the Tmab-induced PD-L1 upregulation. IHC also suggested PD-L1 upregulation after Tmab treatment. CONCLUSIONS: Tmab can upregulate PD-L1 expression on GC cells through interaction with NK cells. These results suggest clinical implications in the assessment of the predictive significance of PD-L1 expression for PD-1 inhibitors.

Fusobacterium nucleatum confers chemoresistance by modulating autophagy in oesophageal squamous cell carcinoma.

BACKGROUND: Fusobacterium nucleatum (F. nucleatum) is a gut microbe implicated in gastrointestinal tumorigenesis. Predicting the chemotherapeutic response is critical to developing personalised therapeutic strategies for oesophageal cancer patients. The present study investigated the relationship between F. nucleatum and chemotherapeutic resistance in oesophageal squamous cell carcinoma (ESCC). METHODS: We examined the relationship between F. nucleatum and chemotherapy response in 120 ESCC resected specimens and 30 pre-treatment biopsy specimens. In vitro studies using ESCC cell lines and co-culture assays further uncovered the mechanism underlying chemotherapeutic resistance. RESULTS: ESCC patients with F. nucleatum infection displayed lesser chemotherapeutic response. The infiltration and subsistence of F. nucleatum in the ESCC cells were observed by transmission electron microscopy and laser scanning confocal microscopy. We also observed that F. nucleatum modulates the endogenous LC3 and ATG7 expression, as well as autophagosome formation to induce chemoresistance against 5-FU, CDDP, and Docetaxel. ATG7 knockdown resulted in reversal of F. nucleatum-induced chemoresistance. In addition, immunohistochemical studies confirmed the correlation between F. nucleatum infection and ATG7 expression in 284 ESCC specimens. CONCLUSIONS: F. nucleatum confers chemoresistance to ESCC cells by modulating autophagy. These findings suggest that targeting F. nucleatum, during chemotherapy, could result in variable therapeutic outcomes for ESCC patients.

Frequency and Implications of Paratracheal Lymph Node Metastases in Resectable Esophageal or Gastroesophageal Junction Adenocarcinoma.

OBJECTIVE: We aimed to evaluate the frequency of paratracheal lymph nodes (LN) metastases and their prognostic influence. SUMMARY BACKGROUND DATA: Paratracheal LNs are considered regional nodes in the esophageal cancer classification, but their metastatic rate and influence on survival remain unclear. METHODS: One thousand one hundred ninety-nine patients with resectable esophageal or gastroesophageal junction adenocarcinoma (EAC) (January 2002 and December 2016) in our Gastrointestinal Medical Oncology Database were analyzed. Paratracheal LNs were defined as1R, 1L, 2R, 2L, 4R, and 4L, according to the 8th American Joint Committee on Cancer classification. RESULTS: Of 1199 patients, 73 (6.1%) had positive paratracheal LNs at diagnosis. The median overall survival (OS) of 73 patients with initial paratracheal LN involvement was 2.10 years (range 0.01-10.1, 5-yrs OS 24.2%). Of 1071 patients who were eligible for recurrence evaluation, 70 patients (6.5%) developed paratracheal LN metastases as the first recurrence. The median time to recurrence was 1.28 years (range 0.28-5.96 yrs) and the median OS following recurrence was only 0.95 year (range 0.03-7.88). OS in 35 patients who had only paratracheal LN recurrence was significantly longer than in patients who had other recurrences (median OS 2.26 vs 0.51 yrs, 5-yrs OS; 26.8% vs 0%, P < 0.0001). Higher T stage (T3/T4) was an independently risk factor for paratracheal LN recurrence (odds ratio 5.10, 95% confidence interval 1.46-17.89). We segregated patients in 3 groups based on the distance of tumor's proximal edge to esophagogastric junction (low; ≤2 cm, medium; 2.0-7.0 cm, and high; >7.0 cm). Paratracheal LN metastases were more frequent with the proximal tumors (low, 4.2%; medium, 12.0%; high, 30.3%; Cochran-Armitage Trend test, P < 0.001). CONCLUSION: Paratracheal LN metastases were associated with a shorter survival in resectable EAC patients. Alternate approaches to prolong survival of this group of patients are warranted.