Abstract Library

#4158 Transcriptomic analysis of PanNET tumor progression from microtumor to metastasis in MEN1 patients

Introduction: Pancreatic Neuroendocrine Neoplasms (PanNENs) are a major component the Multiple Endocrine Neoplasia 1 Syndrome (MEN1). Although multiple pancreatic neuroendocrine microtumors (microadenomatosis) are a histomorphological hallmark of MEN1, their molecular status compared to PanNET as well as their metastasis remains unclear.

Conference:

Presenting Author:

Authors: Chouchane A, Kirchner P, Sylvain Maire R, Schiavo Lena M, Falconi M,

Keywords: Microtumor, MEN1, PanNETs, RNAseq, Transcriptomics, Progression,

#3997 FOXA2-initiated transcriptional activation of INHBA induced by methylmalonic acid promotes pancreatic neuroendocrine neoplasm progression

Introduction: More than 60% of pancreatic neuroendocrine neoplasms (PanNENs) represent metastases when diagnosed. Metabolic alterations have been recognized as one of the hallmarks of tumor metastasis. However, little is known about the molecular mechanism of metabolic changes regulating PanNEN progression.

Conference:

Presenting Author:

Authors: Hu C,

Keywords: metabolic alteration, tumor progression, pancreatic neuroendocrine neoplasm, FOXA2, INHBA, epithelial-mesenchymal transition,

#3989 Hypoxia upregulating ACSS2 enhances lipid metabolism reprogramming through HMGCS1 mediated PI3K/AKT/mTOR pathway to promote the progression of pancreatic neuroendocrine neoplasms

Introduction: Pancreatic neuroendocrine neoplasms (pNENs) are relatively rare. Hypoxia and lipid metabolism-related gene acetyl-CoA synthetase 2 (ACSS2) is involved in tumor progression, but its role in pNENs is not revealed.

Conference:

Presenting Author:

Authors: Gu D, Ye M, Zhu G, Bai J, Tang Q,

Keywords: hypoxia, ACSS2, lipid metabolism reprogramming, HMGCS1, PI3K/AKT/mTOR pathway, pancreatic neuroendocrine neoplasm,

#3974 Small extracellular vesicles miR-183-5p derived from highly invasive pancreatic neuroendocrine tumors reprogram macrophages towards SPP1+ macrophages

Introduction: Highly-metastatic (HM) pancreatic neuroendocrine tumors (pNETs) are characterized by an early occurrence of lymph node and liver metastases and a poor prognosis. Single-cell sequencing analysis showed that HM pNETs had remarkable infiltration of SPP1+ macrophages, which were involved in cell migration, angiogenesis and small extracellular vesicles (sEVs).

Conference:

Presenting Author:

Authors: Zhang W, Xu J, Lou X, Qin Y, Chen J,

Keywords: pancreatic neuroendocrine tumor, p53, small extracellular vesicles, macrophages, SPP1, biomarker,

#3842 Long response to 177-Lu DOTATATE of a long malignant metastatic pheochromocytoma survivor

Introduction: A 64-year-old man was admitted on November 2010 with a CT-scan showing a 9cm right adrenal mass and high 24-hour urine metanephrins and cathecolamins. The mass was resected in December 2010 confirming a pT3N1 pheochromocytoma (PHEO). In May 2013 he presented a local recurrence that was resected proving metastatic lymphatic tissue. On May 2014 biochemical progression preceded a CT scan showing retroperitoneal lymphadenophaties with MIBG uptake. He was then treated with 131I-MIBG (two cycles) until May 2015, having biochemical and radiological response. After lymphatic tumor progression in January 2018, he received two more cycles of 131I-MIBG therapy (cumulative dose 800mCi) with proven refractory disease. He continued follow-up until two new abdominal masses appeared in October 2020. A high uptake in the 99Tc octreotide scintigraphy showed somatostatin receptors expression. The patient refused to participate in a clinical trial, so he was treated off-label with 177Lu-DOTATATE (800mCi) four doses from February to July 2021 achieving a near-complete response.

Conference:

Presenting Author: Martin Fernandez de Soignie A

Authors: Martin Fernandez de Soignie A, Martinez Moreno E, Antón-Pascual B, Pantin Gonzalez C, Sanchez Baños N,

Keywords: pheochromocytoma, 177-Lutetium,