Abstract 84P
Background
Neuroendocrine neoplasms (NENs) are a subgroup of poorly characterized rare tumors with challenging management. NENs are very heterogeneous and the identification of clinically useful biomarkers for patient stratification and treatment tailoring is urgently needed. This study proposes the use of near-patient models based on autologous extracellular matrix (aECM)-scaffolds and zebrafish (ZF) xenografts coupled with next generation sequencing techniques for the phenotype and genotype mapping of primary NEN cells. The aims are: to identify indolent versus aggressive behaviors, to define NEN sensitivity to drugs and to uncover the molecular signatures associated with these phenotypes.
Methods
Primary tumor cells isolated from surgical specimens of NEN patients were cultured in aECM scaffolds or injected into ZF embryos. In aECM scaffolds we evaluated cell morphology and neuroendocrine differentiation. In ZF we evaluated distant invasiveness and angiogenesis ability. For each primary culture, we performed transcriptome analysis of the tumor tissue compared to the healthy counterpart.
Results
Hitherto, we derived three primary cultures of neuroendocrine Merkel cell carcinoma (MCC) and one from grade 1 ileal NEN. The 3 MCC cultures into ZF embryos showed metastatic rates of 81%, 50% and 64%, indicative of tumor aggressiveness. For one MCC culture, angiogenic ability was also observed. The ileal cells were derived from both primary and metastatic lesions. Cells from the primary tumor showed a metastatic rate of 23%, while the ones from the metastasis of 79%. This result highlights the fidelity of ZF xenografting to the tumor behavior in the patient. RNA-seq was performed on Merkel's tumor specimens and bioinformatic analysis showed that ECM remodeling and regulation of apoptotic processes were the most enriched pathways.
Conclusions
We developed aECM scaffolds and ZF xenografts as personalized disease models integrated with multi-omics analysis. This study is expected to generate knowledge on NEN molecular signatures for disease aggressiveness and sensitivity to therapy. All identified markers will be correlated with clinical outcomes of enrolled patients, to validate their significance and clinical utility.
Clinical trial identification
IRSTB120.
Legal entity responsible for the study
IRCCS Istituto Romagnolo per lo Studio dei Tumori (IRST) \"Dino Amadori\", Meldola, Italy IRCCS Istituto Romagnolo per lo Studio dei Tumori (IRST) \"Dino Amadori\", Meldola, Italy.
Funding
Italian Ministry of Health.
Disclosure
All authors have declared no conflicts of interest.