SOMAscan proteomic analysis identifies significantly elevated levels of IL-8 and MPIF-1 isoforms in the BM plasma and PB serum samples of patients with AML. (A) Boxplot shows the relative abundance of IL-8 displayed in relative fluorescence units (RFUs) in the BM plasma samples from patients with AML (n = 10) vs healthy control subjects (n = 10) obtained using the SOMAscan platform. ***P = .0001, vs control using unpaired Mann-Whitney U test. (B) Boxplots show the levels of CKβ8 (left panel) and CKβ8-1 (right panel) isoforms in the BM plasma samples from patients with AML (n = 10) vs healthy control subjects (n = 10) obtained using the SOMAscan platform. ****P < .0001; ***P = .0003, vs control using unpaired Mann-Whitney U test. (C) Boxplots show the relative abundance of CKβ8 (left panel) and CKβ8-1 (right panel) isoforms in the PB serum samples from patients with AML (n = 10) vs healthy control subjects (n = 10) analyzed by using the SOMAscan platform. ****P < .0001; *** P = .0007, vs control using unpaired Mann-Whitney U test. (D) CKβ8 protein levels in the PB serum samples from patients with MDS (n = 9) and patients with AML (n = 24) vs healthy control subjects (n = 20) were analyzed by using ELISA. *P = .0436 for MDS group; **P = .0095 for AML group, vs control using unpaired Mann-Whitney U test. (E) Effect of CKβ8 and CKβ8-1 isoforms on colony formation by CD34⁺ progenitor cells. Results are given as the mean of 2 technical replicates. Significant reduction in CFU-GM and CFU-GEMM was observed when treated with either isoform at 50 ng/mL concentration. P < .05, vs control using a 2-tailed Student unpaired t test.