Kallergi G, Tsintari V, Sfakianakis S, et al. - Given the importance of circulating tumor cells (CTCs) in metastatic dissemination of cancer but the difficulty is faced in detecting and characterizing them because of their limited number in the bloodstream and their mesenchymal features, researchers looked for novel biomarkers to address these issues. A subgroup of 24 genes, potentially overexpressed in CTCs, was identified via bioinformatics functional enrichment analysis. Following prioritization based on the CXCR4 corresponding pathways, they further analyzed five molecules (JUNB, YWHAB, TYROBP, NFYA, and PRDX1) in biological samples. The expression pattern of all the examined molecules was determined by using the SKBR3, MDA-MB231, and MCF7 cell lines, as well as peripheral blood mononuclear cells from normal (n = 10) blood donors as controls. Consequently, they used the following combinations of antibodies: CK (cytokeratin)/CXCR4/JUNB, CK/NFYA/ΥWHΑΒ (14-3-3), and CK/TYROBP/PRDX1, to analyze 100 previously untreated metastatic breast cancer patients (n = 100). In CTCs, the overexpression of CXCR4, JUNB, and TYROBP was identified but the poor prognosis was observed only in relation to the expression of JUNB, affording a novel biomarker and a potential therapeutic target for the elimination of CTCs.