Abstract 1328: Development of endoscopic ultrasound-guided fine-needle aspirate (EUS-FNA) derived pancreatic cancer cell lines from advanced stage cancers

Abstract Background: The investigation of primary cancer cells are becoming more critical in studying various solid cancers which are comprised of heterogeneous groups of cells including the tumor initiating or cancer stem cells. As only 10 to 15% of all pancreatic cancers are applicable for surgical intervention due to the advanced stage discovery, endoscopic ultrasound (EUS) provides as a unique tool to acquire tissue specimen for developing primary cell cultures. With our success from previous pilot study in culturing primary cells of PDAC from EUS-aspirates, we have investigated the feasibility of developing such cell lines from sequential group of PDAC patients, in particular unresectable cases of PDAC where the surgical specimen would not be commonly available. Methods: Under IRB approved protocol at UC Davis Medical Center, consecutive patients with suspected pancreatic mass lesions were included. After cytopathological diagnosis of adenocarcinoma, additional EUS fine-needle aspirate (FNA) specimens were obtained from each PDAC patient. Needle aspirates were processed as follows: the FNA specimen was immediately transferred into a microfuge tube containing fresh media with antibiotics/antimycotics and kept at refrigeration temperature for a few hours prior to further processing. Subsequently, the tube was centrifuged (1000 x g for 3 min) and treated with collagenase IV for 1 hr at 37oC then it was passed through 40 um mesh. Flow-through was then plated onto a treated tissue culture plate in a defined serum-free media and incubated at 37oC with 5% CO2. The media was exchanged at least every other day. Once the primary cells were grown, tumor formation was confirmed in mouse xenograft (NOD mice). Cell viability (XTT) assay was performed with gemcitabine treatment (1uM) against the cells comparing to commercially available PDAC cell lines (MiaPACA2, Panc-1, BxPC3). Results: We enrolled 40 patients with suspected pancreatic mass for the study. Thirty-six patients were subsequently diagnosed with PDAC. Of the 36 patients, preoperative unresectable stages (stage III and IV) included 11 patients. Microbial contamination precluded successful cell culture development in 7 cases including 3 in the unresectable stages. Development of cell culture was possible from 7 patients, where 5 cases were from the stages III and IV PDAC cases. Thus, we have successfully developed PDAC primary cell lines in 5 out of 8 advanced unresectable PDAC cases. The primary cells showed significantly more resistance to gemcitabine compared to commercial cell lines. Conclusion: As previously demonstrated, EUS-FNA derived primary cell culture development is possible. Further improvement in sampling and culturing technique would enhance the yield and expansion of the PDAC cell lineages for further investigation. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1328. doi:1538-7445.AM2012-1328