Primary gastric non-Hodgkin lymphomas: Recent advances regarding disease pathogenesis and treatment

Metabolism-related ALDH1B1 acts as potential predictor and therapeutic target for primary gastrointestinal diffuse large B-cell lymphoma

Primary gastrointestinal diffuse large B-cell lymphoma (PGI-DLBCL) is the most common extra-nodal DLBCL. Metabolism-related factors have been associated with tumor progression, but the relationship between abnormal metabolism and prognosis of PGI-DLBCL remains unelucidated. In our study, consensus clustering based on metabolism-related genes classified PGI-DLBCL patients into two metabolic subtypes, and poor prognosis was associated with immunosuppressive microenvironment. A prognostic signature based on five metabolism-related genes (APOE, ALDH6 A1, PLOD2, IKBKB and ALDH1B1) was developed. Patients in high-risk group had a worse prognosis, with an immunosuppressive microenvironment. Moreover, 159 PGI-DLBCL patients were enrolled and divided into training cohort (n = 87) and validation cohort (n = 72). Univariate and multivariate Cox regression analysis showed metabolism-related factors were independent prognostic factors in PGI-DLBCL. A novel model (A-IPI score) combining APOA and NCCN-IPI was developed, and A-IPI score was better than NCCN-IPI score in predicting the prognosis of PGI-DLBCL patients. Furthermore, immunohistochemistry showed that ALDH1B1 was highly expressed in PGI-DLBCL and patients with high ALDH1B1 expression displayed worse prognosis. Moreover, cell proliferation assay revealed that the treatment with IGUANA-1, ALDH1B1 inhibitor, suppressed cell proliferation in DLBCL and IGUANA-1 exerted synergistic anti-tumor effects with PI3K inhibitor duvelisib. Additionally, we found that immune scores, ESTIMATE scores, and stromal scores were higher and the immune checkpoints (CTLA-4, PD-1, PD-L1) were down-regulated in patients with high ALDH1B1 expression. Collectively, our study constructed a novel metabolism-related prognostic model and highlighted the potential of metabolism-related gene ALDH1B1 as prognostic biomarker and drug target in PGI-DLBCL, providing new insights for the development of precision therapies in PGI-DLBCL patients.

Cystatin SN (CST1) Is a Poor Independent Prognostic Biomarker for Gastrointestinal Diffuse Large B-Cell Lymphoma

BACKGROUND Gastrointestinal diffuse large B-cell lymphoma (GI-DLBCL) is the most common histological subtype of extra-nodal DLBCL, but the risk factors, prognostic biomarkers, histopathological classifications, and treatment strategies have not had significant progress. Emerging evidence shows that cystatin SN (CST1) is involved in tumor progression in several cancer types, but its role in GI-DLBCL has not been revealed. MATERIAL AND METHODS We established a cohort consisting of 84 patients with GI-DLBCL who underwent surgical resection. The expression of CST1 in the cohort was investigated by immunohistochemistry, which divided the patients into subgroups with low or high expression of CST1. Moreover, the CST1 expression in GI-DLBCL tissues or adjacent GI tissues were compared with RT-qPCR. The correlation between CST1 expression and clinicopathological factors was analyzed with the chi-square test. The prognostic significance of CST1 was estimated by univariate and multivariate analysis, and statistical significance was analyzed with the log-rank test. RESULTS CST1 was aberrantly upregulated in GI-DLBCL tissues compared with in non-tumor GI tissues. High expression of CST1 indicated poor prognosis of GI-DLBCL (P=0.012), and CST1 can be regarded as an independent prognostic biomarker of GI-DLBCL (hazard ratio=3.07). In our study, serum lactate dehydrogenase (P=0.002), performance status (P=0.003), Lugano stage (P=0.002), and International Prognostic Index (P=0.001) were also prognostic factors of GI-DLBCL. CONCLUSIONS CST1 is an independent prognostic biomarker of GI-DLBCL, indicating unfavorable prognosis. Our results suggested that CST1 detection can be a promising method to stratify high-risk patients and guide individual treatment.

Upregulation of Actin-Related Protein 2 (ACTR2) Exacerbated the Malignancy of Diffuse Large B-Cell Lymphoma through Activating Wnt Signaling

This investigation mainly explores the roles of actin-related protein 2 (ACTR2) in diffuse large B-cell lymphoma (DLBCL). We first assessed the level of ACTR2 and its association with the overall survival (OS) of DLBCL. The results indicated that ACTR2 was upregulated in DLBCL and was associated with unfavorable prognosis of DLBCL. Next, the effect of ACTR2 knockdown or overexpression on DLBCL was evaluated in vitro. Our investigation revealed that ACTR2 depletion inhibited the malignant behaviors of DLBCL cells; whereas, ACTR2 abundance promoted those behaviors. Besides, ACTR2 activated the Wnt signaling in DLBCL and exerted its oncogenic influence on DLBCL through Wnt signaling in vitro and in vivo. To summarize, our study implicated that ACTR2 was a promising therapeutic target for DLBCL, which might become a novel direction to improve our understanding on DLBCL.

Ascites as First Atypical and Only Clinical Manifestation of De Novo Follicular Lymphoma

Follicular lymphoma is the most common indolent non-Hodgkin’s lymphoma and is usually initially detected in lymph nodes. Primary extranodal NHL is most commonly primarily localized in the gastrointestinal tract. We present one unusual case of ileum FL with ascites as the first clinical sign. The 73-year-old female patient was presented to the emergency department for evaluation of mild abdominal pain and abdominal swelling that had been going on for three days followed by bloating and occasional pain in the spine. The abdominal contrast-enhanced CT revealed the contrast stagnation in the distal part of the ileum. The ileum wall about 11 cm in length was thickened up to 2.9 cm and the tumor mass infiltrated all layers of ileum mesenteric lymphadenopathy up to 2 cm in diameter and significant ascites. On the upper ileum wall, the vegetative mass was described 3 cm in diameter. The patient had an emergent laparotomy with the ileocolic resection and latero-lateral ileocolic anastomosis. The microscopy finding of terminal ileum and the regional lymph nodes showed domination of cleaved cells with irregular nuclei which correspond to centrocytes. There were 0–15 large non-cleaved cells corresponding to centroblast in the microscopy high-power field. The final diagnosis was follicular lymphoma, the clinical stage 2E and histological grade by Berard and Mann criteria 1–2.

The epidemiology and prognosis of patients with primary gastric T-cell lymphoma in the SEER program

BACKGROUND

Primary gastric T-cell lymphoma (PG-TCL) is a rare hematological malignancy with few data reported. The objective of this study is to investigate the epidemiology, clinical characteristics, and survivals of PG-TCL.

METHODS

Totally, 164 patients with PG-TCL from 1975 to 2016 extracted from the Surveillance, Epidemiology, and End Results Program (SEER) database were analyzed. Kaplan-Meier method was applied to plot overall survival (OS) and cancer-specific survival (CSS). The prognostic factors of OS and CSS were explored by Cox proportional hazard regression. Nomograms were constructed to predict survival possibilities.

RESULTS

The age-adjusted incidence rate of PG-TCL was 0.0091 per 100,000 person-years and increased with age. The median age at onset was 65 years old with male predominance. The major histological type was peripheral T-cell lymphoma, NOS (63.4%). The 1-, 2-, and 5-year OS were 45.5%, 34.7%, and 23.5%, respectively while the 1-, 2-, and 5-year CSS were 47.4%, 37.3%, and 29.6%, respectively. Multivariate Cox analysis demonstrated that age at diagnosis, use of chemotherapy, and radiotherapy were the independent prognostic factors for OS. Chemotherapy combined with radiotherapy could significantly improve patients' OS compared with chemotherapy alone. Moreover, age at diagnosis and use of chemotherapy were also the independent prognostic factors for CSS. Nomograms for PG-TCL were developed to predict 1-, 2-, and 5-year OS possibilities. The predictability of nomograms was verified by high concordance index and good agreement with the predicted value in calibration plots.

CONCLUSION

PG-TCL is a rare neoplasm with low incidence. Patients with PG-TCL generally exhibited poor prognosis. Use of chemotherapy plus radiotherapy was associated with favorable OS.

Protein Loss Enteropathy as an Initial Presentation of Gastric Epstein–Barr Virus Lymphoma

Protein loss enteropathy (PLE) is a complex disease process that can result in potentially fatal protein losses. Gastrointestinal protein losses usually arise from damage to the gastrointestinal mucosa or from lymphatic obstruction. The goal of management is to identify and treat the underlying causes and maintain normal serum protein levels. Here, we present a patient with diarrhea and generalized edema, with decreased serum albumin and gamma-globulin levels, concerning for protein loss enteropathy. He was ultimately found to be positive for HIV infection, and his stool alpha-1 antitrypsin levels were diagnostic of protein loss enteropathy. His endoscopic and histologic evaluation revealed gastric Epstein–Barr virus-encoded small RNA- (EBER-) positive lymphoma. Though gastrointestinal lymphomas are known to cause PLE, this will be the first documented case of EBER-positive gastric lymphoma presenting with PLE. We hope to bring awareness to this unique presentation to aid in expedient diagnosis and treatment to avoid delays in treatment and potentially fatal outcomes.