Jie Li

BACKGROUND: To determine the origin of the neoplastic cell in central nervous system (CNS) hemangioblastomas in von Hippel-Lindau disease (VHL) and its role in tumor formation and distribution, we characterized and differentiated neoplastic cells from hemangioblastomas removed from VHL patients. METHODS AND FINDINGS: A total of 31 CNS hemangioblastomas from 25 VHL patients were resected and analyzed. Tumor cells from the hemangioblastomas were characterized, grown, and differentiated into multiple lineages. Resected hemangioblastomas were located in the cerebellum (11 tumors), brainstem (five tumors), and spinal cord (15 tumors). Consistent with an embryologically derived hemangioblast, the neoplastic cells demonstrated coexpression of the mesodermal markers brachyury, Flk-1 (vascular endothelial growth factor-2), and stem cell leukemia (Scl). The neoplastic cells also expressed hematopoietic stem cell antigens and receptors including CD133, CD34, c-kit, Scl, erythropoietin, and erythropoietin receptor. Under specific microenvironments, neoplastic cells (hemangioblasts) were expanded and differentiated into erythrocytic, granulocytic, and endothelial progenitors. Deletion of the wild-type VHL allele in the hematopoietic and endothelial progeny confirmed their neoplastic origin. CONCLUSIONS: The neoplastic cell of origin for CNS hemangioblastomas in VHL patients is the mesoderm-derived, embryologically arrested hemangioblast. The hematopoietic and endothelial differentiation potential of these cells can be reactivated under suitable conditions. These findings may also explain the unique tissue distribution of tumor involvement.

Circulating tumor DNA (ctDNA) in peripheral blood is a "liquid biopsy" that contains representative tumor information including gene mutations. Additionally, repeated ctDNA samples can be easily obtained to monitor response to treatment and disease progression, which may be especially valuable to lung cancer patients with tumors that cannot be easily biopsied or removed. To investigate the changes in ctDNA after surgical tumor resection, tumor and blood samples obtained before and after surgery were collected prospectively from 41 non-small lung cancer (NSCLC) patients. Somatic driver mutations in tumor DNA (tDNA) and pre- and post-op plasma ctDNA sample pairs were identified by targeted sequencing in several genes including EGFR, KRAS, and TP53 with an overall study concordance of 78.1% and sensitivity and specificity of 69.2% and 93.3%, respectively. Importantly, the frequency of 91.7% of ctDNA mutations decreased after surgery and these changes were observed as little as 2 days post-op. Moreover, the presence of ctDNA had a higher positive predictive value than that of six tumor biomarkers in current clinical use. This study demonstrates the use of targeted sequencing to reliably identify ctDNA changes in response to treatment, indicating a potential utility of this approach in the clinical management of NSCLC.

2509 Background: As a promising approach for some cancers, chimeric antigen receptor T cell therapy has limited success in solid tumors. Claudin18.2 (CLDN 18.2) is a stomach-specific isoform of Claudin-18, and highly expressed in gastric and pancreatic adenocarcinoma, the advanced form of both of which have urgent unmet medical needs. We previously developed and demonstrated ability of CLDN 18.2-specific CAR (CAR-CLDN18.2) T cells to eradicate CLDN 18.2-positive gastric cancer xenografts without obvious on-target off-tumor toxicity (Huang J. JNCI 2018). Methods: In this single-arm, open-label, first-in-human phase I pilot study (NCT03159819) to investigate the safety and explore the efficacy of the autologous CAR-CLDN18.2 T cells, patients with confirmed CLDN 18.2 positive advanced gastric or pancreatic adenocarcinoma aged 18 to 70 years received 1 or more cycles of CAR-CLDN18.2 T cell infusion(s) after lymphodepletion pretreatment (fludarabine and cyclophosphamide, with or without nab-paclitaxel) until disease progression or presence of intolerable toxicity. Adverse Event (AE) grade categorization is according to CTCAE 4.0, and tumor response was assessed per RECIST 1.1. Results: As of November 30th, 2018, 12 subjects with metastatic adenocarcinoma (7 gastric and 5 pancreatic) were treated with 1–5 cycles (total of 0.5 - 55 X 10 8 ) of CAR-positive T cells infusions. There were no serious adverse events, treatment-related death or severe neurotoxicity occurred in the study. No grade 4 AEs except for decreased lymphocytes, neutrophils and white blood cells. All cytokine release syndromes observed were grade 1 or 2. Among the 11 evaluable subjects, 1 achieved a complete response (gastric adenocarcinoma), 3 had partial responses (2 gastric adenocarcinomas and 1 pancreatic adenocarcinoma), 5 had stable disease and 2 had progression of disease. The total objective response rate was 33.3%, with median PFS of 130 days estimated using Kaplan-Meier method [95% CI (38, 230)]. Conclusions: This clinical study indicated that CAR-CLDN18.2 T cell therapy were safe and well tolerated and may have promising therapeutic efficacy in patients with advanced gastric and pancreatic adenocarcinoma. Clinical trial information: NCT03159819.

// Xianjuan Kou 1,* , Xingran Liu 2,* , Xianbing Chen 3 , Jie Li 2 , Xiaoqi Yang 2 , Jingjing Fan 1 , Yi Yang 1 and Ning Chen 1 1 Hubei Key Laboratory of Sport Training and Monitoring, College of Health Science, Wuhan Sports University, Wuhan, China 2 Graduate School, Wuhan Sports University, Wuhan, China 3 College of Medicine, Hubei University for Nationalities, Enshi, China * These authors have contributed equally to this work Correspondence to: Ning Chen, email: // Keywords : ampelopsin, aging, autophagy, miR-34a, SIRT1-mTOR signal pathway, Gerotarget Received : July 15, 2016 Accepted : October 17, 2016 Published : October 21, 2016 Abstract The underlying molecular mechanisms for aging-related neurodegenerative diseases such as Alzheimer’s disease (AD) are not fully understood. Currently, growing evidences have revealed that microRNAs (miRNAs) are involved in aging and aging-related diseases. The up-regulation of miR-34a has been reported to be associated with aging-related diseases, and thus it should be a promising therapeutic target. Ampelopsin, also called dihydromyricetin (DHM), a natural flavonoid from Chinese herb Ampelopsis grossedentata , has been reported to possess multiple pharmacological functions including anti-inflammatory, anti-oxidative and anti-cancer functions. Meanwhile, it has also gained tremendous attention against neurodegenerative diseases as an anti-aging compound. In the present study, the model rats with D-gal-induced brain aging revealed an obvious expression of miR-34a; in contrast, it could be significantly suppressed upon DHM treatment. In addition, target genes associated with miR-34a in the presence of DHM treatment were also explored. DHM supplementation inhibited D-gal-induced apoptosis and rescued impaired autophagy of neurons in hippocampus tissue. Moreover, DHM activated autophagy through up-regulated SIRT1 and down-regulated mTOR signal pathways due to the down-regulated miR-34a. In conclusion, DHM can execute the prevention and treatment of D-gal-induced brain aging by miR-34a-mediated SIRT1-mTOR signal pathway.