PROS1 and glioblastoma: Alterations of SGCG, HTR4, ITGB1, CPS1 and PROS1 were detected in 26.6% of samples (8 out of 30 patients) and were slightly increased in patients with anaplastic astrocytoma (37.5%) compared to GBM (22.7%), as well as in the samples with low level of total genomic instability (38.5% vs. 17.64% with high instability).