Chondroitin Sulfate Proteoglycan CSPG4 as a Novel Hypoxia-Sensitive Marker in Pancreatic Tumors

(A) Systemic levels of sCSPG4 were determined by ELISA in sera (USCN/Cloud-Clone Corp. kit; n = 83) of healthy volunteers and patients with chronic pancreatitis (CP), serous cystadenoma (SCA), premalignant (dysplastic IPMN^dys and IPMN^tis), and malignant (IPMN with an associated invasive carcinoma, IPMN^inv) forms of intraductal papillary-mucinous neoplasm, as well as in ductal (PDAC), adenosquamous (AdSq) and anaplastic (Anapl) carcinomas. The data are summarized to show individual values, median level, and interquartile range (IQR). (B) The ROC analyses of the ELISA data showed the discriminatory power of sCSPG4 levels for patients with different pancreatic diseases. The dotted green line represents the median level of the particular cohort used to estimate the frequency of the sCSPG4 underexpressers in the panel (C), as detailed in Materials and Methods. (D–E) Validation of ELISA findings in an independent cohort (n = 221). Red-bordered areas indicate subgroups depicting IPMN and PDAC progression. The patients’ characteristics and results of statistical analyses are presented in the main text and Tables 1 and 2. (F) Validation of ELISA findings with a different ELISA kit (CUSABIO; n = 64).