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Colon cancer is the third most common cancer in the world and the second most common cause of cancer-related mortality. Molecular biomarkers for colon cancer have undergone vigorous discovery and validation. Recent studies reported that overexpression of podocalyxin-like protein 1 (PODXL) is associated with distant metastasis and poor prognosis across several types of malignancies. Its role and underlying molecular mechanism, however, are not yet fully understood. In the present study, we revealed that the Hippo transducer, the transcriptional coactivator with PDZ-binding motif (TAZ), acts as a downstream mediator of PODXL in colon cancer. Inhibition of PODXL resulted in the suppression of TAZ signaling and the downregulation of Hippo downstream genes. Moreover, PODXL plays a critical role in cancer stemness, invasiveness, and sensitivity to chemotherapies in colon cancer HCT15 cells. Notably, expression of PODXL showed a positive correlation with stem-like and epithelial-mesenchymal transition (EMT) core signatures, and was associated with poor survival outcomes in patients with colon cancer. These findings provide novel insights into the molecular mechanism of PODXL-mediated tumorigenesis in colon cancer.

A simple but effective electrochemical route to functionalize graphene is demonstrated. Cyclic voltammetric sweeps (CV) are performed in a 0.5 M H 2 SO 4 aqueous solution on electrodes consisting of carbon cloth, graphene, and Nafion ionomer. Upon exposure to ambient oxygen, the formation of hydroxyl radicals from the oxygen reduction reaction during the CV cycles initiates the decomposition of the Nafion ionomer, which produces oxygenated functional groups on the graphene surface. Using contact angle measurements and X-ray photoelectron spectroscopy, various amounts of Nafion ionomer are explored to determine the optimum conditions for graphene functionalization. Afterwards, Pd 9 Ru nanoparticles with an average size of 3-4 nm are synthesized and impregnated on functionalized graphene (FGN). To prepare core-shell electrocatalysts, Pd 9 Ru/FGN is subjected to Cu underpotential deposition followed by a galvanic displacement reaction to deposit a Pt monolayer on the Pd 9 Ru surface (Pd 9 Ru@Pt). The assynthesized sample (Pd 9 Ru@Pt/FGN) exhibits enhanced performance in methanol electrooxidation, which includes a better activity and lower susceptibility to poisoning by intermediates. The electrochemically active surface area (ECSA) of Pd 9 Ru@Pt/FGN shows a value that is 1.5-fold larger than that of Pd 9 Ru@Pt on untreated graphene (Pd 9 Ru@Pt/GN). In the durability tests, Pd 9 Ru@Pt/FGN and Pd 9 Ru@Pt/GN demonstrate losses in the ECSA of 14.9% and 30.3%, respectively.