Multiplexed glycan immunofluorescence identification of pancreatic cancer cell subpopulations in both tumor and blood samples.

Pancreatic ductal adenocarcinoma (PDAC) tumor heterogeneity impedes the development of biomarker assays for early disease detection. We hypothesized that PDAC cell subpopulations could be identified by aberrant glycan signatures in both tumor tissue and blood samples. We used multiplexed glycan immunofluorescence to distinguish between PDAC and noncancer cell subpopulations within tumor tissue, and we developed hybrid glycan sandwich assays to determine whether the aberrant glycan signatures could be detected in blood samples.

A rigorous multi-laboratory study of known PDAC biomarkers identifies increased sensitivity and specificity over CA19-9 alone.

A blood test that enables surveillance for early-stage pancreatic ductal adenocarcinoma (PDAC) is an urgent need. Independent laboratories have reported PDAC biomarkers that could improve biomarker performance over CA19-9 alone, but the performance of the previously reported biomarkers in combination is not known. Therefore, we conducted a coordinated case/control study across multiple laboratories using common sets of blinded training and validation samples (132 and 295 plasma samples, respectively) from PDAC patients and non-PDAC control subjects representing conditions under which surveillance occurs.

Multiplexed Glycan Immunofluorescence Identification of Pancreatic Cancer Cell Subpopulations in Both Tumor and Blood Samples.

Pancreatic ductal adenocarcinoma (PDAC) tumor heterogeneity impedes the development of biomarker assays suitable for early disease detection that would improve patient outcomes. The CA19-9 glycan is currently used as a standalone biomarker for PDAC. Furthermore, previous studies have shown that cancer cells may display aberrant membrane-associated glycans.

A Rigorous Multi-Laboratory Study of Known PDAC Biomarkers Identifies Increased Sensitivity and Specificity Over CA19-9 Alone.

A blood test that enables surveillance for early-stage pancreatic ductal adenocarcinoma (PDAC) is an urgent need. Independent laboratories have reported PDAC biomarkers that could improve biomarker performance over CA19-9 alone, but the performance of the previously reported biomarkers in combination is not known. Therefore, we conducted a coordinated case/control study across multiple laboratories using common sets of blinded training and validation samples (132 and 295 plasma samples, respectively) from PDAC patients and non-PDAC control subjects representing conditions under which surveillance occurs.

The Framing Preference for Large and Increasing Components in Static and Dynamic Descriptions.

Describing sets in terms of a two-valued variable, either value can be chosen: exam results may be referred to by pass rates or fail rates. What determines such framing choices? Building on work by McKenzie and colleagues on reference points in the production and interpretation of framed information, we investigate two determinants of frame choice. One is that speakers tend to focus on the component that has increased vis-à-vis a previous state, the other is the tendency to choose the component larger than 50%.

Detection of Chemotherapy-resistant Pancreatic Cancer Using a Glycan Biomarker, sTRA.

Purpose: A subset of pancreatic ductal adenocarcinomas (PDACs) is highly resistant to systemic chemotherapy, but no markers are available in clinical settings to identify this subset. We hypothesized that a glycan biomarker for PDACs called sialylated tumor-related antigen (sTRA) could be used for this purpose.

Experimental Design: We tested for differences between PDACs classified by glycan expression in multiple systems: sets of cell lines, organoids, and isogenic cell lines; primary tumors; and blood plasma from human subjects.

Overexpression of HGF/MET axis along with p53 inhibition induces de novo glioma formation in mice.

Background: Aberrant MET receptor tyrosine kinase (RTK) activation leads to invasive tumor growth in different types of cancer. Overexpression of MET and its ligand hepatocyte growth factor (HGF) occurs more frequently in glioblastoma (GBM) than in low-grade gliomas. Although we have shown previously that HGF-autocrine activation predicts sensitivity to MET tyrosine kinase inhibitors (TKIs) in GBM, whether it initiates tumorigenesis remains elusive.

The sTRA Plasma Biomarker: Blinded Validation of Improved Accuracy Over CA19-9 in Pancreatic Cancer Diagnosis.

Purpose: The CA19-9 biomarker is elevated in a substantial group of patients with pancreatic ductal adenocarcinoma (PDAC), but not enough to be reliable for the detection or diagnosis of the disease. We hypothesized that a glycan called sTRA (sialylated tumor-related antigen) is a biomarker for PDAC that improves upon CA19-9.

Experimental Design: We examined sTRA and CA19-9 expression and secretion in panels of cell lines, patient-derived xenografts, and primary tumors.

Differential responses of MET activations to MET kinase inhibitor and neutralizing antibody.

Background: Aberrant MET tyrosine kinase signaling is known to cause cancer initiation and progression. While MET inhibitors are in clinical trials against several cancer types, the clinical efficacies are controversial and the molecular mechanisms toward sensitivity remain elusive.

Methods: With the goal to investigate the molecular basis of MET amplification (MET) and hepatocyte growth factor (HGF) autocrine-driven tumors in response to MET tyrosine kinase inhibitors (TKI) and neutralizing antibodies, we compared cancer cells harboring MET (MKN45 and MHCCH97H) or HGF-autocrine (JHH5 and U87) for their sensitivity and downstream biological responses to a MET-TKI (INC280) and an anti-MET monoclonal antibody (MetMab) in vitro, and for tumor inhibition in vivo.

Mining High-Complexity Motifs in Glycans: A New Language To Uncover the Fine Specificities of Lectins and Glycosidases.

Knowledge of lectin and glycosidase specificities is fundamental to the study of glycobiology. The primary specificities of such molecules can be uncovered using well-established tools, but the complex details of their specificities are difficult to determine and describe. Here we present a language and algorithm for the analysis and description of glycan motifs with high complexity.

Cartilage-specific deletion of Mig-6 results in osteoarthritis-like disorder with excessive articular chondrocyte proliferation.

A deficiency of mitogen-inducible gene-6 (Mig-6) in mice leads to the development of an early-onset, osteoarthritis (OA)-like disorder in multiple synovial joints, underlying its importance in maintaining joint homeostasis. Here we determined what joint tissues Mig-6 is expressed in and what role chondrocytes play in the Mig-6-deficient OA-like disorder. A Mig-6/lacZ reporter mouse strain expressing β-galactosidase under the control of the Mig-6 gene promoter was generated to determine Mig-6 expression in joint tissues.

Strengthening context-dependent anticancer effects on non-small cell lung carcinoma by inhibition of both MET and EGFR.

The MET and EGFR receptor tyrosine kinases (RTK) are often coexpressed and may cross-talk in driving the development and progression of non-small cell lung carcinoma (NSCLC). In addition, MET amplification is an alternative resistance mechanism for escaping EGFR-targeted therapy. To assess the benefits of combined targeting of MET and EGFR for treating NSCLCs, we investigated the activities of these two RTK pathways in NSCLC cell lines and evaluated their responses to SGX523 and erlotinib, the small-molecule kinase inhibitors of MET and EGFR, respectively.

Cancer-type regulation of MIG-6 expression by inhibitors of methylation and histone deacetylation.

Epigenetic silencing is one of the mechanisms leading to inactivation of a tumor suppressor gene, either by DNA methylation or histone modification in a promoter regulatory region. Mitogen inducible gene 6 (MIG-6), mainly known as a negative feedback inhibitor of the epidermal growth factor receptor (EGFR) family, is a tumor suppressor gene that is associated with many human cancers. To determine if MIG-6 is inactivated by epigenetic alteration, we identified a group of human lung cancer and melanoma cell lines in which its expression is either low or undetectable and studied the effects of methylation and of histone deacetylation on its expression.

MET kinase inhibitor SGX523 synergizes with epidermal growth factor receptor inhibitor erlotinib in a hepatocyte growth factor-dependent fashion to suppress carcinoma growth.

The hepatocyte growth factor (HGF)-MET pathway supports several hallmark cancer traits, and it is frequently activated in a broad spectrum of human cancers (http://www.vai.org/met/).