FOXA2-initiated transcriptional activation of INHBA induced by methylmalonic acid promotes pancreatic neuroendocrine neoplasm progression.

Pancreatic neuroendocrine neoplasms (PanNENs) are a group of highly heterogeneous neoplasms originating from the endocrine islet cells of the pancreas with characteristic neuroendocrine differentiation, more than 60% of which represent metastases when diagnosis, causing major tumor-related death. Metabolic alterations have been recognized as one of the hallmarks of tumor metastasis, providing attractive therapeutic targets. However, little is known about the molecular mechanism of metabolic changes regulating PanNEN progression. In this study, we first identified methylmalonic acid (MMA) as an oncometabolite for PanNEN progression, based on serum metabolomics of metastatic PanNEN compared with non-metastatic PanNEN patients. One of the key findings was the potentially novel mechanism of epithelial-mesenchymal transition (EMT) triggered by MMA. Inhibin ßA (INHBA) was characterized as a key regulator of MMA-induced PanNEN progression according to transcriptomic analysis, which has been validated in vitro and in vivo. Mechanistically, INHBA was activated by FOXA2, a neuroendocrine (NE) specific transcription factor, which was initiated during MMA-induced progression. In addition, MMA-induced INHBA upregulation activated downstream MITF to regulate EMT-related genes in PanNEN cells. Collectively, these data suggest that activation of INHBA via FOXA2 promotes MITF-mediated EMT during MMA inducing PanNEN progression, which puts forward a novel therapeutic target for PanNENs.

Efficacy and safety of modified endoscopic submucosal tunnel dissection for superficial esophageal circumferential lesions.

To evaluate the efficacy and safety of intra-tunnel dissection using hemostatic forceps and needle-type device for patients with esophageal circumferential lesions (ECLs). Patients with ECLs were enrolled in the study and underwent endoscopic submucosal tunnel dissection (ESTD) or hemostatic forceps-based ESTD (ESFTD). All patients were divided into three subgroups according to longitudinal length of the lesions (LLLs): >8 cm, 4-8 cm and < 4 cm. The clinical data such as gender, age, length of lesions and operating time were collected. A total of 152 patients were included in this study and comprised 80 cases of ESFTD and 72 cases of ESTD. The procedure time was markedly shorter in the ESFTD group than in the ESTD group (P < 0.001). Moreover, ESFTD significantly increased the rate of complete resection and reduced specimen injury in LLLs >8 cm and 4-8 cm subgroup compared with ESTD (P < 0.001), but not in <4 cm subgroup (P > 0.05). The perforation and infection rate were similar in ESFTD and ESTD group (P > 0.05). However, ESFTD effectively decreased the muscular injury rate' the duration of chest pain and the time from endoscopic surgery to first occurrence of esophageal stenosis compared with ESTD group (P < 0.01). ESFTD has better efficacy and safety than ESTD in the treatment of ECLs, especially for large lesions. ESFTD could be recommended for patients with ECLs.