<p>Representative time plot of oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) measurements & migratory and AMPK phosphorylation response to CXCL12 of patient-derived pancreatic cancer cells ; Characterization of murine-derived pancreatic cancer cells ; CXCL12-induced AMPK activity is Gαi and CXCR4 dependent ; CXCL12-induced AMPK activity is calcium dependent ; Cytostatic CXCL12 stimulates MYPT1 phosphorylation at T853 .</p>
<p>Representative time plot of oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) measurements & migratory and AMPK phosphorylation response to CXCL12 of patient-derived pancreatic cancer cells ; Characterization of murine-derived pancreatic cancer cells ; CXCL12-induced AMPK activity is Gαi and CXCR4 dependent ; CXCL12-induced AMPK activity is calcium dependent ; Cytostatic CXCL12 stimulates MYPT1 phosphorylation at T853 .</p>
e23029 Background: Immune escape is a hallmark of cancer and emerging immunotherapies have shown great promise in promoting favorable patient outcomes. In this study, we hypothesized that immunosuppression would modify the humoral response to tumor-associated proteins (autoantigens) and have a profound impact on survival. With this, we aimed to identify and characterize the differences in serum autoantibody composition in stage IV NSCLC patient groups based on clinical outcomes. Methods: Whole cell lysates prepared from stage IV NSCLC tumors (n = 5) were fractionated via reversed-phase HPLC followed by two-dimensional gel electrophoresis. Proteins were immunoblotted in parallel against pooled serum from patient groups (n = 20 each) representing “Good” (progression free survival (PFS) ≥ 6 mo.) and “Poor” (PFS < 6 mo.) treatment outcomes. Proteins found to be differentially immunoreactive in association with these groups were selected using PDQuest v7.3 (BioRad) software package followed by protein identification using an LTQ XL ion trap mass spectrometer. Protein identities were determined using the MassMatrix software v2.0 package, searching both the human genome and a decoy database and employing a threshold sequence coverage of 30% and a Pro-score threshold of 100. Results: A total of12 discrete proteins with outcome-based immunoreactivity were cored and identified based on the findings from the immunoproteomic analysis using a minimum threshold of 2-fold difference in immunoreactivity and p ≤ 0.05. From these findings, autoantibodies against α-enolase, cathepsin D, and triose phosphate isomerase were found to be uniquely present in the cases where PFS was less than 6 months, whereas junction plakoglobulin, macrophage capping protein, and glyceraldehyde phosphate dehydrogenase were found to be uniquely associated with a “good” clinical outcome. Conclusions: We have identified a series of new candidate biomarkers that may have promise as an alternate means to select patients for therapies modulating immune checkpoint inhibition. Studies confirming the prognostic value of these candidate biomarkers in the Luminex platform are currently underway with a cohort of first-line NSCLC patients.
