The NF-YA splicing signature controls aggressiveness of colon cancer by regulating different modes of cell migration and cell metabolism.

NF-Y is a transcription factor composed of NF-YA and NF-YB/NF-YC subunits. The two NF-YA isoforms, NF-YAs and NF-YAl, differentially control cell proliferation and differentiation. TCGA data highlight increased NF-YA expression, specifically NF-YAs, in colorectal cancer (CRC), the second most deadly cancer worldwide. Despite this, patients with high NF-YAl mRNA levels have a lower overall survival probability. We demonstrate that NF-YAl overexpression can generate a hybrid epithelial-mesenchymal transition (EMT) state in CRC cells by direct transcriptional regulation of key EMT genes. Consistently, NF-YAl enhances cell migration, both in 2D and 3D culture conditions, as highlighted by live imaging investigations. While collective migration characterizes NF-YAs-cells, fast single-cell and amoeboid-like migration marks NF-YAl cells. In agreement with these results, NF-YAl overexpression promotes cell dissemination in zebrafish xenografts. Since metabolic reprogramming is a hallmark of cancer and metastasis, we also investigated the role of NF-YAl in the metabolism of CRC cells. The measure of mitochondrial fuel usage in live cells showed that NF-YAl overexpression enhances the dependency and capacity for glutamine pathway, one of the key metabolic pathways involved in EMT and cell dissemination. Specifically, we identified NF-YAl as direct transcriptional regulator of GLS1 glutaminase and GLUL glutamine synthetase. Our observations imply that the two NF-YA variants can be potentially novel markers for CRC patient stratification. Higher NF-YAl expression can be a hallmark of cancer cell dissemination by affecting cell metabolism and cell migratory abilities.