Objective:To explore the coexisting gene mutations of FLT3-ITD mutation and its association with partial clinical parameters in acute myeloid leukemia (AML).Methods:The clinical data of 236 newly diagnosed AML outpatients and hospitalized patients of Changzhou No.2 People's Hospital and the Second People's Hospital of Wuxi between December 2012 and August 2019 were retrospectively analyzed. Genome DNA-polymerase chain reaction (PCR) combined with Sanger sequencing was used to detect FLT3-ITD mutations, and 51 tumor target gene mutations in patients with FLT3-ITD mutations were detected by using high-throughput DNA sequencing combined with Sanger sequencing.Results:Among 236 AML patients, FLT3-ITD mutations were found in 71 cases (30.1%). About 97.2% (69/71) patients with FLT3-ITD mutations were accompanied by additional mutations, of which 19 patients harbored double coexisting genes mutations, 24 patients harbored 3 coexisting genes mutations and 26 patients harbored ≥ 4 coexisting genes mutations. The most common coexisting genes mutations were NPM1 (55 cases, 77.5%), followed by DNMT3A (36 cases, 50.7%), TET2 (9 cases, 12.7%), CEBPA (5 cases, 7.0%), IDH1 (4 cases, 5.6%) and NRAS (4 cases, 5.6%). In FLT3-ITD mutation group, the hemoglobin level of patients with DNMT3A mutation type was lower than that of those with DNMT3A wild type ( t = -2.37, P = 0.020); the hemoglobin level of patients with NPM1 mutation type was higher than that of those with NPM1 wild type ( t = 2.04, P = 0.045). The platelet in patients with 3 mutations and ≥ 4 mutations was higher than that in those with double mutations ( χ2 = 7.72, P = 0.021). After chemotherapy in 71 patients, the curative effect of 66 cases was evaluable, and the white blood count of 18 patients who did not reach complete remission was higher than that of 48 patients who reached complete remission ( Z = -2.74, P = 0.006). Conclusions:Most FLT3-ITD mutated patients with AML commonly show coexisting gene mutations, and the mutation types of coexisting genes are correlated with the clinical features of patients.

OBJECTIVETo explore the mechanism of NK cell dysfunction in patients with multiple myeloma (MM).

METHODSThe expression of inhibitory receptors (CD158a and CD158b) and activating receptors NKG2D and NCRs (NKp30, NKp44 and NKp46) on CD3-CD56+NK cell of 13 MM patients and 30 healthy controls were analyzed by flow cytometry. The concentration of soluble NKG2D ligands (MICA, MICB, ULBP1, ULBP2 and ULBP3) in serum was detected by enzyme- linked immunosorbent assay (ELISA), and the cytotoxicity of NK cell against MM cell line by flow cytometry.

RESULTSThere are no significant differences of percentage and absolute number of NK cells, and the expression level of CD158a and CD158b between MM patients and healthy individuals (P>0.05). No NKp44 expression was detected on fresh isolated NK cells from both groups. There is no difference in inhibitor receptors expression between MM patients and healthy individuals but the expression of NKG2D, NKp30 and NKp46 on NK cells were higher in MM patients as compared with that in healthy individuals. The concentration of soluble NKG2D ligands in serum was higher in MM patients as compared with that in healthy individuals (P<0.05). Cultured healthy individual's NK cells with MM patient's serum could significantly decrease its cytotoxicity against MM cell line U266 cells [(38.5 ± 6.5) % vs (25.4 ± 5.9)%, P=0.044］.

CONCLUSIONThe higher level of soluble NKG2D ligands in serum may be the mechanism of NK cell dysfunction in MM patient.

Cells, Cultured ; Flow Cytometry ; Humans ; Killer Cells, Natural ; metabolism ; pathology ; Multiple Myeloma ; immunology ; metabolism ; NK Cell Lectin-Like Receptor Subfamily K ; metabolism ; Natural Cytotoxicity Triggering Receptor 1 ; metabolism ; Natural Cytotoxicity Triggering Receptor 2 ; metabolism ; Natural Cytotoxicity Triggering Receptor 3 ; metabolism ; Receptors, KIR2DL1 ; metabolism ; Receptors, KIR2DL3 ; metabolism