Nucleolar spindle associated protein 1 (NUSAP1) facilitates proliferation of hepatocellular carcinoma cells

The most fundamental characteristic of cancer cells is abnormal proliferation, which is partly due to deregulation of cell cycle. Nucleolar spindle associated protein 1 (NUSAP1) is originally identified as microtubule and chromosome binding protein and takes an important role in chromosome segregation fidelity. Recent studies have been documented that NUSAP1 is associated with the progression of several cancers. However, its expressions and functions are unclear in hepatocellular carcinoma (HCC).

qPCR and western blotting were used to examine NUSAP1 levels in fresh paired HCC tissues and corresponding adjacent normal liver tissues (ANT). MTT and colony formation assay were performed to evaluate whether NUSAP1 can influence the proliferation of HCC cells. Anchorage-independent growth assay was implemented to detect the effect of NUSAP1 on in vitro tumorigenicity capacity. Flow cytometry, qPCR and western blotting assay were used to clarify the detailed mechanisms that NUSAP1 accelerates the capability for cell proliferation and in vitro tumorigenicity.

Firstly, we analyzed the availably public dataset The Cancer Genome Atlas (TCGA), and discovered that NUSAP1 is dramatically upregulated in HCC tissues and closely correlated with poor prognosis of patients suffering HCC, which was confirmed in fresh HCC tissues and ANT. Subsequently, cell function assay illustrated that the upregulation of NUSAP1 facilitates proliferation and in vitro tumorigenicity capacity of HCC cells. Besides, molecular experiments suggested that NUSAP1 promotes cell cycle transition of HCC cells.

In summary, the above results inferred that NUSAP1 takes an indispensable role in cell cycle progression. And it might be served as a novel prognostic factor in HCC.