During chronic infection with Helicobacter pylori , Schlafen 4-expressing myeloid-derived suppressor cells (SLFN4 + MDSCs) create a microenvironment favoring intestinal metaplasia and neoplastic transformation. SLFN4 can be induced by IFN-α, which is mainly secreted from plasmacytoid dendritic cells (pDCs). This study tested the hypothesis that Helicobacter pylori infection promotes SLFN4 + MDSC differentiation by inducing pDCs to secrete IFN-α. C57BL/6 mice were gavaged with H. pylori and infection lasted 2, 4, or 6 months. The mouse pDCs were isolated from the bone marrow from wild type C57BL/6J mice. The results showed that H. pylori infection increased the number of SLFN4 + MDSCs by inducing IFN-α expression in mice. Further mechanistic experiments unraveled that IFN-α induced SLFN4 transcription by binding to the SLFN4 promoter. Furthermore, H. pylori infection stimulated pDCs to secrete IFN-α by activating the TLR9-MyD88-IRF7 pathway. Collectively, Helicobacter pylori infection promotes SLFN4 + MDSC differentiation by inducing secretion of IFN-α from pDCs.

Pancreatic acinar cell carcinoma (PACC) is a rare tumor of the exocrine pancreas. It accounts for only 1% of all pancreatic malignancies. A 39-year woman sought treatment for repeated abdominal pain and jaundice. The computed tomography (CT) and magnetic resonance imaging (MRI) suggested diffuse enlargement of the pancreas. 18 F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/CT showed diffuse enlargement of the pancreas and increased glucose uptake. The endoscopic ultrasound-guided fine-needle aspiration (EUS-FNA) biopsy of the pancreas was performed, and the case was finally diagnosed as PACC. After the sixth course of chemotherapy with gemcitabine and albumin paclitaxel, a CT scan showed significant shrinkage of the pancreas. PACC very rarely presents with diffuse enlargement of the pancreas. This case illustrates a rare presentation of PACC with diffuse pancreatic enlargement, which was effectively treated with gemcitabine and albumin paclitaxel chemotherapy.

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Introduction: Intraoral benign and malignant nerve sheath tumors (BNST and MNST) are rare tumors with non-specific clinical presentations and represent diagnostic and therapeutic challenges. Current knowledge regarding their demographic, clinicopathological features and treatments remains fragmented. Materials and Methods: The original data about patients diagnosed as intraoral BNST and MNST were retrieved from our disease registry (2005–2017). Comprehensive reviews of English and Chinese literature were performed to collect and analyze the epidemiological, clinicopathological data and treatment outcomes about those published cases. Results: Thirty-four intraoral BNSTs were found at our institution in the past 13 years. Literature reviews identified 354 intraoral BNSTs in 223 articles and 60 intraoral MNSTs in 50 articles. Most intraoral BNSTs and MNSTs were presented in the second to fifth decade of life. Males outnumbered females in MNSTs, while BNSTs displayed a slight female preponderance. The common sites for intraoral BNSTs were parapharyngeal space followed by tongue, whereas mandible was the most common site for MNSTs. Most intraoral BNSTs were presented as slow-growing, painless mass or swelling, while MNSTs usually appeared as painful and invasive mass with discomfort. Surgical excision was preferred for intraoral BNSTs with excellent prognosis. Complete resection was indicated for intraoral MNST with dismal prognosis as evidenced by much recurrence, metastasis, and death. Conclusion: Intraoral BNST and MNST are rare diseases which should not be ignored when intraoral painless or painful mass/swelling is found. Surgical excision is indicated for intraoral BNST with favorable outcomes. However, further investigations are warranted to optimize the treatment for intraoral MNST to improve its prognosis.