Down-regulation of Sphk2 suppresses bladder cancer progression

Abstract

Bladder cancer is the second most common urological malignancy around the world and is by far the most frequent urological malignancy in China. The abnormal expression of sphingosine kinase 2 (SphK2) is associated with tumor progression and a poor patient survival rate, however, the effect of SphK2 on the bladder cancer cells remains unclear. The aim of the paper was to study the expression of SphK2 in bladder cancer and the role of SphK2 on the cell proliferation, metastasis, and apoptosis in bladder cancer in vitro. Our results showed that SphK2 is up-regulated in bladder cancer tissues compared with the corresponding adjacent non-neoplastic tissues, and the expression level of SphK2 was significantly higher in human bladder cancer cells in comparison with normal bladder epithelial cells. Silencing of SphK2 could inhibit the proliferation ability of T24 cells in vitro. In addition, SphK2 knockdown could induce a significant increase in the number of apoptotic cells. Furthermore, the transwell assay also showed significant cell migration inhibition in SphK2 siRNA transfectant compared with cell lines transfected with NC. Thus, this study suggested that SphK2 inhibition may provide a promising treatment for bladder cancer patients.

MicroRNA-613 inhibits cell growth, migration and invasion of papillary thyroid carcinoma by regulating SphK2

“…Increasing evidence suggests that alterations in SphK2 expression contribute to the pathogenesis of many human cancers [29–31]. SphK2 overexpression in bladder cancer cells is closely implicated in tumor progression.…”

“…SphK2 overexpression in bladder cancer cells is closely implicated in tumor progression. Silencing of SphK2 might inhibit the proliferation and migration of bladder cancer cells [29]. Knockdown of SphK2 leads to decreased proliferation and enhanced chemosensitivity and apoptosis to gefitinib in non-small cell lung cancer [30].…”

“…Immunohistochemical (IHC) stainingwas performed as previously described using anti-SphK2((Santa Cruz Biotechnology, Santa Cruz, CA, USA) [29]. The degree of immunostaining of SphK1 proteins was scored by two observers blinded to clinical data.…”

Validation of commercially available sphingosine kinase 2 antibodies for use in immunoblotting, immunoprecipitation and immunofluorescence

“…Furthermore, the ECM Biosciences SK2 antibody produced many intense non-specific bands in all cell lines tested, demonstrating poor selectivity. This antibody has been used for IB analyses in multiple publications 12– 15 , suggesting that it may be more suitable with other cell/tissue systems or conditions not tested here. However, in agreement with our findings, the IB analysis performed by the manufacturer also showed various prominent non-specific bands in HeLa lysates.…”

“…We have examined a rabbit polyclonal SK2 antibody from Proteintech, which is raised against amino acids 266–618 of recombinant human SK2a, and a rabbit polyclonal SK2 antibody from ECM Biosciences, which is raised against a synthetic peptide corresponding to amino acids 36–52 of human SK2a. The Proteintech SK2 antibody has been previously utilized in one publication for IB 11 , and the ECM Biosciences SK2 antibody has been used in multiple publications for IB 12– 15 and for IF 16 .…”