A clinically feasible multiplex proteomic immunoassay as a novel functional diagnostic for pancreatic ductal adenocarcinoma

Abstract

To date, targeted therapy for pancreatic ductal adenocarcinoma (PDAC) remains largely unsuccessful in the clinic. Current genomics-based technologies are unable to reflect the quantitative, dynamic signaling changes in the tumor, and require larger tumor samples that are difficult to obtain in PDAC patients. Therefore, a highly sensitive functional tool that can reliably and comprehensively inform intra-tumoral signaling events is direly needed to guide treatment decision. We tested the utility of a highly sensitive proteomics-based functional diagnostic platform, Collaborative Enzyme Enhanced Reactive-immunoassay (CEERTM), on fine-needle aspiration (FNA) samples obtained from 102 patients with radiographically-evident pancreatic tumors. Two FNA passes were collected from each patient, hybridized to customized chips coated with an array of capture antibodies, and detected using two enzyme-conjugated antibodies which emit quantifiable signals. We demonstrate that this technique is highly sensitive in detecting total and phosphorylated forms of multiple signaling molecules in FNA specimens, with reasonable correlation of marker intensities between two different FNA passes. Notably, signals of several markers were significantly higher in PDAC compared to non-cancerous samples. In PDAC samples, we found high total c-Met signal to be associated with poor survival, and confirmed this finding using an independent PDAC tissue microarray.

Tumor–Stroma IL1β-IRAK4 Feedforward Circuitry Drives Tumor Fibrosis, Chemoresistance, and Poor Prognosis in Pancreatic Cancer

“…FFPE PDAC samples were retrieved from the Department of Pathology and Immunology at WUSTL under IRB approval (#201404143). WUSTL PDAC TMA with survival data was constructed by Dr. Dengfeng Cao at WUSTL, was IRB approved and published (25). Patient consent was waived for both set of samples under IRB approval.…”

TPL2 enforces RAS-induced inflammatory signaling and is activated by point mutations

“…The Washington University PDAC TMA was IRB approved (no. 201404143) and previously published (65). Patient consent was waived per IRB approval.…”

Phospho-Ser784-VCP Drives Resistance of Pancreatic Ductal Adenocarcinoma to Genotoxic Chemotherapies and Predicts the Chemo-Sensitizing Effect of VCP Inhibitor

“…The PDAC TMA consisting of totally 165 separate PDAC tumors (each with duplicate cores) has been previously described [28,33]. In this study, 24 samples that were either depleted or lacked sufficient number of tumor cells for accurate scoring were excluded.…”

“…To seek clinical evidence for the functional importance of pSer 784 -VCP for DNA repair and PDAC cell survival upon chemotherapy treatments, we examined the intratumoral levels of pSer 784 -VCP in patient tumor samples of a clinically annotated PDAC tissue microarray (TMA) by immunohistochemistry (IHC) [33,46]. Nearly all patients in this cohort received standard post-surgery chemotherapy treatments consisting of genotoxic agents such as gemcitabine, 5FU, and cisplatin.…”