Enhanced casein kinase II (CK II) activity in human lung tumours.

BACKGROUND

Casein kinase II (CK II) is expressed at a higher level in lung tumours when compared to the corresponding non-neoplastic lung tissue.

MATERIALS AND METHODS

The aim of the present study was to evaluate the activity of CK II both in neoplastic and non-neoplastic human lung tissue by using a synthetic peptide with Arg-Arg-Arg-Asp-Asp-Asp-Ser-Asp-Asp-Asp (RRRDDDSDDD) sequence. One unit of CK II activity is defined as the amount catalysing the transfer of 1 pmol 32P into the substrate within 1 minute at 37 degrees C.

RESULTS

The activities measured for the neoplastic and non-neoplastic tissues were 1250-1500 U/mg protein and 100-500 U/mg protein, respectively. According to these results, the maximum activity observed in the lung carcinomas was 2 to 3-fold higher than the lung tumour specimens when compared to the non-neoplastic lung tissue. The activity range of CK II was between 500-1500 U mg protein.

CONCLUSION

Our results suggest that CK II plays an important role in cellular proliferation and the mechanism of its activation.