Development and Validation Study of the Prognostic Impact of Deep Learning-Determined Myxoid Stroma After Neoadjuvant Chemotherapy in Patients with Esophageal Squamous Cell Carcinoma.

PURPOSE: This study was designed to investigate the prognostic significance of artificial intelligence (AI)-based quantification of myxoid stroma in patients undergoing esophageal squamous cell carcinoma (ESCC) surgery after neoadjuvant chemotherapy (NAC) and to verify its significance in an independent validation cohort from another hospital. METHODS: We evaluated two datasets of patients with pathological stage II or III ESCC who underwent surgery after NAC. Cohort 1 consisted of 85 patients who underwent R0 surgery for the primary tumor after NAC. Cohort 2, the validation cohort, consisted of 80 patients who received same treatments in another hospital. AI-based myxoid stroma was evaluated in resected specimens, and its area was categorized by using the receiver operating characteristic curve for overall survival (OS) of cohort 1. RESULTS: The F1 scores, which are the degree of agreement between the automatically detected myxoid stroma and manual annotations, were 0.83 and 0.79 for cohorts 1 and 2. The myxoid stroma-high group had a significantly poorer prognosis than the myxoid stroma-low group in terms of OS, disease-specific survival (DSS), and recurrence-free survival (RFS) in cohort 1. Comparable results were observed in cohort 2, where OS, DSS, and RFS were significantly affected by myxoid stroma. Multivariate analysis for RFS revealed that AI-determined myxoid stroma-high was one of the independent prognostic factors in cohort 1 (hazard ratio [HR] 1.97, p = 0.037) and cohort 2 (HR 4.45, p < 0.001). CONCLUSIONS: AI-determined myxoid stroma may be a novel and useful prognostic factor for patients with pathological stage II or III ESCC after NAC.

Immunogenic characteristics of microsatellite instability-low esophagogastric junction adenocarcinoma based on clinicopathological, molecular, immunological and survival analyses.

Microsatellite instability (MSI) is categorized by mutation frequency: high MSI (MSI-H), low MSI (MSI-L) and microsatellite stable (MSS). MSI-H tumors have a distinct immunogenic phenotype, with immunotherapies using checkpoint inhibitors already approved for the treatment of MSI-H gastroesophageal adenocarcinoma (GEA); this is not observed for MSI-L or MSS. Here, we tested the hypothesis that MSI-L tumors are also a distinct phenotype and potentially immunogenic. MSI-PCR assays (BAT25, BAT26, BAT40, D2S123, D5S346 and D17S250) were performed on 363 Epstein-Barr virus-negative, surgically resected esophagogastric junction (EGJ) adenocarcinoma samples. Tumors were characterized as MSI-H (≥2 markers), MSI-L (1 marker) or MSS (0 markers). CD8+ cell counts, PD-L1 and HER2 expression levels, TP53 mutations, epigenetic alterations and prognostic significance were also examined. All pathological and molecular experiments were conducted using serial, whole-tumor sections of chemo-naïve surgical specimens. MSI-H and MSI-L were assigned to 28 (7.7%) and 24 (6.6%) cases, respectively. Compared to MSS cases, MSI-L cases had significantly higher intratumoral CD8+ cell infiltration (P = .048) and favorable EGJ cancer-specific survival (multivariate hazard ratio = 0.35, 95% CI, 0.12-0.82; P = .012). MSI-L tumors were also significantly associated with TP53-truncating mutations as compared to MSI-H (P = .009) and MSS (P = .012) cases, and this trend was also observed in GEA data from The Cancer Genome Atlas (TCGA). Indel mutational burden among TCGA MSI-L tumors was significantly higher than that of MSS tumors (P = .016). These results suggest that MSI-L tumors may have a distinct tumor phenotype and be potentially immunogenic in EGJ adenocarcinoma.

Recent Incidence Trend of Surgically Resected Esophagogastric Junction Adenocarcinoma and Microsatellite Instability Status in Japanese Patients.

BACKGROUND: The incidence trend of esophagogastric junction (EGJ) adenocarcinoma in Japan has not been sufficiently investigated. Little is known about the microsatellite instability (MSI) status of this tumor. SUMMARY: Previously published studies analyzing the trend of EGJ adenocarcinoma in Japan were reviewed. And a trend of surgically resected cases (Siewert type I-III) utilizing a retrospective multicenter cohort of 379 patients from 4 academic institutions in Japan investigated. Although an increasing trend in the last 2 reports was considered controversial, our cohort demonstrated a growing number of EGJ adenocarcinoma cases between 2006 and 2013. This trend was evident, especially in Siewert type I cases. In the previous 16 studies that performed MSI testing, MSI-high tumors ranged 0-8.3%, though there were no fixed microsatellite markers on EGJ adenocarcinoma. In a recent comprehensive genetic analysis by The Cancer Genome Atlas, MSI testing using the following 7 markers, BAT25, BAT26, BAT40, D2S123, D5S346, D17S250 and TGFR-II showed a favorable correlation with hypermutated tumors. We performed MSI testing using 6 of those markers, except TGFR-II, on 206 cases from one institution, and detected 15 cases (7.3%) with MSI-high. The prevalence of MSI-high was 0% in Siewert type I, 7.6% in type II, and 16.7% in type III. Key message: The number of surgically resected EGJ adenocarcinoma cases gradually increased, and MSI-high was infrequent in Siewert type I-II tumors in our Japanese cohort. Considering MSI-high as a predictive biomarker for emerging immune checkpoint inhibitors, MSI status is becoming more beneficial in EGJ adenocarcinoma.

Innate immunomodulation with recombinant interferon-alpha enhances resistance of rainbow trout (Oncorhynchus mykiss) to infectious hematopoietic necrosis virus.

We examined the in vivo immunostimulatory effects of a recombinant Atlantic salmon (Salmo salar) interferon-alpha2 (rSasaIFN-alpha2). The mature rSasaIFN-alpha2, expressed and purified from Escherichia coli, was administered to rainbow trout (Oncorhynchus mykiss) via the oral, immersion, or intraperitoneal (IP) injection route. Injection of rSasaIFN-alpha2 at 0.1microg/g fish gave significantly greater protection than a phosphate buffered saline (PBS) injection against a lethal challenge of infectious hematopoietic necrosis virus (IHNV), with a relative percent survival of 39%. Relative percent survival (RPS) increased significantly to 92% when the fish were injected with rSasaIFN-alpha2 at 1microg/g fish. Antiviral protection was evident for up to 7 days post-injection of rSasaIFN-alpha2. Administration of rSasaIFN-alpha2 by the oral or immersion route was not protective, and the fish succumbed to virus infection. The level of systemic IFN-induced expression of the Mx1 gene was significantly greater (p<0.01) in the IFN-injected group than in the PBS-injected group, and this was correlated with the fish survival rates in the challenge study. We used relative quantitative real-time polymerase chain reactions to examine the systemic expression of several other IFN-induced genes (including genes for IFN1, IFN regulatory factors 1 and 2, MHC-I, STAT1, vig-1, and GBP) and found that their expression was significantly increased 1-day post-rSasaIFN-alpha2 injection. Expression of the IFN-gamma and interleukin-1beta genes was not significantly increased. Thus, a salmonid rIFN-alpha can modulate the innate immune response of rainbow trout and mediate early antiviral protection against IHNV.

Rapid detection of a fish iridovirus using loop-mediated isothermal amplification (LAMP).

A loop-mediated isothermal amplification (LAMP) procedure is described to detect the genomic DNA molecule of red seabream iridovirus (RSIV), a fish iridovirus belonging to the Iridoviridae family. The RSIV DNA was amplified using DNA extracts obtained from spleen of infected red seabream, Pagrus major and from various RSIV isolates. The method was at least 10 times more sensitive than conventional PCR in detecting for the presence of RSIV. A striking feature of the LAMP reaction is its ability to synthesize a large amount of DNA leading to the production of a white precipitate, magnesium pyrophosphate, as a by-product. The presence or absence of this white precipitate facilitates easy detection of the RSIV genomic DNA without the use of gel electrophoresis. A strong correlation exists between the amount of input viral DNA copy and the corresponding turbidity reading at the end of the reaction; hence, the LAMP reaction may be used potentially to quantify RSIV particles in the infected fish.