Ovarian cancer G protein-coupled receptor 1 in-hibits A549 cells Migration through Casein kinase 2α intronless gene

We have previously reported that ovarian cancer G protein-coupled receptor 1 (OGR1) is a new metastasis suppressor gene. We have also reported for the first time that a new intronless gene for casein kinase 2 (CSNK2A3) is expressed in human cells. The promoter of the well-known casein kinase 2 (CSNK2A1) displays characteristics of housekeeping gene whereas CSNK2A3 has a characteristic of a regulated promoter with two TATA boxes and a CAAT box. In this study, we found that OGR1 up-regulates expression of CSNK2A3 by about 3 folds in A549 cells but not CSNK2A1. OGR1 also up-regulates expression of neutral endopeptidase (NEP). The OGR1 induced inhibition of A549 cell migration is completely abrogated by inhibition of casein kinase 2 activity, whereas partial abrogation (~ 30%) was observed in the presence of NEP inhibition. The results also revealed that OGR1 regulates CSNK2A3 via activation of Rac1/cdc42 and MAPKs pathways. CK2 is ubiquitously expressed and in contrast it is believed to be a constitutively active enzyme and its regulation appears to be independent of known second messengers. There is no previous report on how expression of CK2 in cancer cells is regulated although many studies have report of aberrant expression of the kinase in cancer. In the current study, we are reporting for the first time the regulation of intronless casein kinase 2 gene, CSNK2A3 in cancer cells. Our findings suggest that the aberrantly casein kinase 2 expression found in various cancer cells may the due to CSNK2A3 expression which is potentially regulated by several master regulators of the developmental pathways rather than well-known casein kinase 2 gene, CSNK2A1.