microRNA 125a Regulates MHC-I Expression on Esophageal Adenocarcinoma Cells, Associated With Suppression of Antitumor Immune Response and Poor Outcomes of Patients.

BACKGROUND & AIMS: Immune checkpoint inhibition may affect growth or progression of highly aggressive cancers, such as esophageal adenocarcinoma (EAC). We investigated the regulation of expression of major histocompatibility complex, class 1 (MHC-I) proteins (encoded by HLA-A, HLA-B, and HLA-C) and the immune response to EACs in patient samples. METHODS: We performed quantitative polymerase chain reaction array analyses of OE33 cells and OE19 cells, which express different levels of the ATP binding cassette subfamily B member 1 (TAP1) and TAP2, required for antigen presentation by MHC-I, to identify microRNAs (miRNAs) that regulate their expression. We performed luciferase assays to validate interactions between miRNAs and potential targets. We overexpressed candidate miRNAs in OE33, FLO-1, and OACP4 C cell lines and performed quantitative polymerase chain reaction, immunoblot, and flow cytometry analyses to identify changes in messenger RNA (mRNA) and protein expression; we studied the effects of cytotoxic T cells. We performed miRNA in situ hybridization, RNA-sequencing, and immunohistochemical analyses of tumor tissues from 51 untreated patients with EAC in the Netherlands. Clinical and survival data were collected for patients, and EAC subtypes were determined. RESULTS: We found OE19 cells to have increased levels of 7 miRNAs. Of these, we found binding sites for miRNA 125a (MIR125a)-5p in the 3' untranslated region of the TAP2 mRNA and binding sites for MIR148a-3p in 3' untranslated regions of HLA-A, HLA-B, and HLA-C mRNAs. Overexpression of these miRNAs reduced expression of TAP2 in OE33, FLO-1, and OACP4 C cells, and reduced cell-surface levels of MHC-I. OE33 cells that expressed the viral peptide BZLF1 were killed by cytotoxic T cells, whereas OE33 that overexpressed MIR125a-5p or MIR 148a along with BZLF1 were not. In EAC and nontumor tissues, levels of MIR125a-5p correlated inversely with levels of TAP2 protein. High expression of TAP1 by EAC correlated with significantly shorter overall survival times of patients. EACs that expressed high levels of TAP1 and genes involved in antigen presentation also expressed high levels of genes that regulate the adaptive immune response, PD-L1, PD-L2, and IDO1; these EACs had a poor response to neoadjuvant chemoradiotherapy and associated with shorter overall survival times of patients. CONCLUSIONS: In studies of EAC cell lines and tumor tissues, we found increased levels of MIR125a-5p and MIR148a-3p to reduce levels of TAP2 and MHC-I, required for antigen presentation. High expression of MHC-I molecules by EAC correlated with markers of an adaptive immune response and significantly shorter overall survival times of patients.

Defining Benchmarks for Transthoracic Esophagectomy: A Multicenter Analysis of Total Minimally Invasive Esophagectomy in Low Risk Patients.

OBJECTIVE: To define "best possible" outcomes in total minimally invasive transthoracic esophagectomy (ttMIE). BACKGROUND: TtMIE, performed by experts in patients with low comorbidity, may serve as a benchmark procedure for esophagectomy. PATIENTS AND METHODS: From a cohort of 1057 ttMIE, performed over a 5-year period in 13 high-volume centers for esophageal surgery, we selected a study group of 334 patients (31.6%) that fulfilled criteria of low comorbidity (American Society of Anesthesiologists score ≤2, WHO/ECOG score ≤1, age ≤65 years, body mass index 19-29 kg/m). Endpoints included postoperative morbidity measured by the Clavien-Dindo classification and the comprehensive complication index. Benchmark values were defined as the 75th percentile of the median outcome parameters of the participating centers to represent best achievable results. RESULTS: Benchmark patients were predominantly male (82.9%) with a median age of 58 years (53-62). High intrathoracic (Ivor Lewis) and cervical esophagogastrostomy (McKeown) were performed in 188 (56.3%) and 146 (43.7%) patients, respectively. Median (IQR) ICU and hospital stay was 0 (0-2) and 12 (9-18) days, respectively. 56.0% of patients developed at least 1 complication, and 26.9% experienced major morbidity (≥grade III), mostly related to pulmonary complications (25.7%), anastomotic leakage (15.9%), and cardiac events (13.5%). Benchmark values at 30 days after hospital discharge were ≤55.7% and ≤30.8% for overall and major complications, ≤18.0% for readmission, ≤3.1% for positive resection margins, and ≥23 for lymph node yield. Benchmarks at 30 and 90 days were ≤1.0% and ≤4.6% for mortality, and ≤40.8 and ≤42.8 for the comprehensive complication index, respectively. CONCLUSION: This outcome analysis of patients with low comorbidity undergoing ttMIE may serve as a reference to evaluate surgical performance in major esophageal resection.

The dynamics of HER2 status in esophageal adenocarcinoma.

Trastuzumab, a monoclonal antibody against HER2, has become standard of care for metastatic HER2-overexpressing esophagogastric adenocarcinoma and is currently investigated as (neo)adjuvant treatment option in HER2-positive esophagogastric adenocarcinoma. The HER2 status is commonly determined on archived material of the primary tumor. However, this status may change over the course of treatment or disease progression. The aim of this study was to assess the dynamics of HER2 status in esophageal adenocarcinoma (EAC) in patients with resectable and recurrent disease, and to determine the associations of these changes with clinical outcome. Discordance, defined as any change in HER2 status between matched biopsy and post-neoadjuvant chemoradiation therapy resection specimen (N = 170), or between matched resection specimen and recurrence of patients not eligible for curative treatment (N = 61), was determined using the standardized HER2 status scoring system. Clinically relevant positive discordance was defined as a change to HER2 positive status, as this would imply eligibility for HER2-targeted therapy. A difference in HER2 status between biopsy and resection specimen and resection specimen and metachronous recurrence was observed in 2.1% (n = 3) and 3.3% (n = 2) of the paired cases, respectively. Clinically relevant discordance was detected in 1.4% (n = 2) of the resectable patients and 1.6% (n = 1) of the patients with recurrent disease. Patients with HER2-positive status tumors before start of neoadjuvant treatment showed better overall survival, but not statistically significant. No association between HER2 status discordance and survival was found. Clinically relevant HER2 status discordance was observed and in order to prevent under-treatment of patients, the assessment of HER2 status in the metastatic setting should preferably be performed on the most recently developed lesions if the previous HER2 assessment on archival material of the primary tumor was negative.