Summary:

Obesity, and more specifically pancreatic adipose infiltration, is associated with the presence and number of PanIN precancerous lesions. We hypothesized that the composition and pathophysiological role of intralobular fat (ILF) and extralobular fat (ELF) may differ according to the presence and stage of pancreatic precancerous lesions (ADM, PanIN). We also wanted to explore the role played by adipose infiltration in the process of pancreatic oncogenesis.
To this end, we first explored the lipidomic profiles of pancreatic ILF and ELF by MALDI-MSI and looked for specific lipid peaks linked to BMI and PanIN in patients with malignant pancreatic tumors. The results obtained led us to carry out a comparative study between obese and non-obese patients (without malignant tumors) in order to (1) study the transcriptomic profiles of acinar tissue close to ILF (Ac/ILF+) versus acinar tissue without ILF infiltration (Ac/ILF-), (2) evaluate the transcriptomic profile of ELF from obese versus non-obese patients, and (3) characterize precancerous lesions in the context of obesity by morphological and immunohistochemical analyses.

Keywords: Obesity, Intra-lobular and extra-lobular fatty pancreatic infiltration, Pancreatic precancerous lesions, Lipidomic MALDI-TOF imaging mass spectrometry, Pancreatic oncogenesis