Objective:To analyze the clinical features and prognosis of acute B lymphoblastic leukemia (B-ALL) children carrying a TCF3: : PBX1 fusion gene and to evaluate the prognostic value of this gene.Methods:Retrospective cohort study.A total of 2 164 B-ALL children aged 0-18 years diagnosed and treated at 19 pediatric centers from October 2016 to June 2022 were enrolled.They were divided into the positive group and the negative group according to whether they carried a TCF3: : PBX1 fusion gene.The clinical characteristics, treatment response, adverse reactions, and prognosis of the 2 groups of patients were analyzed.The rank sum and Kruskal-Wallis tests were used to compare two and more than two groups of numerical variables, respectively.Fisher′s exact test was used to compare categorical variables.Results:Among the 2 164 patients, 116 (5.4%) were TCF3: : PBX1 positive, of which 70 patients were female, accounting for 60.3%.There were 840 female patients in the TCF3: : PBX1-negative group, accounting for 41.0%.There was a significant difference in the ratio of females between the TCF3: : PBX1-positive and TCF3: : PBX1-negative groups ( P<0.001).No significant difference was observed in age of onset between the two groups( P>0.05).The proportion of bone marrow naive cells [54.00 (14.00, 76.50)% vs.29.00 (3.00, 68.00)%], white blood cell counts [25.30 (10.46, 60.94)×10 9/L vs.9.03 (4.38, 30.73)×10 9/L] and hemoglobin counts [82.00(63.00, 101.00) g/L vs.74.00(60.00, 90.00) g/L] in the TCF3: : PBX1-positive group were significantly higher than those in the negative group at the onset (all P<0.05).In terms of treatment response, the proportion of peripheral blood naive cells on Day 8 in the TCF3: : PBX1-positive group was significantly higher than that in the negative group [2.00 (0, 9.00)% vs.0 (0, 2.00)%, P<0.001].The proportion of minimal residual disease <0.1% on Day 15 in the TCF3: : PBX1-positive group was significantly higher than that in the negative group ( P=0.038).There were no significant differences in cumulative recurrence rate, treatment-related mortality (TRM), and overall survival (OS) between the TCF3: : PBX1-positive group and TCF3: : PBX1-negative group (all P>0.05).The cumulative recurrence risk of TCF3: : PBX1-positive patients was 9.646 times higher than that of ETV6: : RUNX1-positive patients with better prognosis( HR=9.646, 95% CI: 1.026-90.700, P=0.047).There were no significant differences in TRM and OS between TCF3: : PBX1-positive and ETV6: : RUNX1-positive patients (all P>0.05).A significant enrichment of PAX5 mutations was detected in TCF3: : PBX1-positive patients.Among the 7 high-risk TCF3: : PBX1-positive patients in a single center, 4 patients had PAX5 mutations, and this proportion was significantly higher than that in other patients ( P<0.001). Conclusions:B-ALL children carrying a TCF3: : PBX1 fusion gene have a high remission rate and good long-term prognosis after intensive chemotherapy.It is suggesting that TCF3: : PBX1-positive B-ALL patients should be rated at intermediate risk to receive intensive chemotherapy.

Objective:To analyze the clinical features and prognosis of acute B lymphoblastic leukemia (B-ALL) children carrying a TCF3: : PBX1 fusion gene and to evaluate the prognostic value of this gene.Methods:Retrospective cohort study.A total of 2 164 B-ALL children aged 0-18 years diagnosed and treated at 19 pediatric centers from October 2016 to June 2022 were enrolled.They were divided into the positive group and the negative group according to whether they carried a TCF3: : PBX1 fusion gene.The clinical characteristics, treatment response, adverse reactions, and prognosis of the 2 groups of patients were analyzed.The rank sum and Kruskal-Wallis tests were used to compare two and more than two groups of numerical variables, respectively.Fisher′s exact test was used to compare categorical variables.Results:Among the 2 164 patients, 116 (5.4%) were TCF3: : PBX1 positive, of which 70 patients were female, accounting for 60.3%.There were 840 female patients in the TCF3: : PBX1-negative group, accounting for 41.0%.There was a significant difference in the ratio of females between the TCF3: : PBX1-positive and TCF3: : PBX1-negative groups ( P<0.001).No significant difference was observed in age of onset between the two groups( P>0.05).The proportion of bone marrow naive cells [54.00 (14.00, 76.50)% vs.29.00 (3.00, 68.00)%], white blood cell counts [25.30 (10.46, 60.94)×10 9/L vs.9.03 (4.38, 30.73)×10 9/L] and hemoglobin counts [82.00(63.00, 101.00) g/L vs.74.00(60.00, 90.00) g/L] in the TCF3: : PBX1-positive group were significantly higher than those in the negative group at the onset (all P<0.05).In terms of treatment response, the proportion of peripheral blood naive cells on Day 8 in the TCF3: : PBX1-positive group was significantly higher than that in the negative group [2.00 (0, 9.00)% vs.0 (0, 2.00)%, P<0.001].The proportion of minimal residual disease <0.1% on Day 15 in the TCF3: : PBX1-positive group was significantly higher than that in the negative group ( P=0.038).There were no significant differences in cumulative recurrence rate, treatment-related mortality (TRM), and overall survival (OS) between the TCF3: : PBX1-positive group and TCF3: : PBX1-negative group (all P>0.05).The cumulative recurrence risk of TCF3: : PBX1-positive patients was 9.646 times higher than that of ETV6: : RUNX1-positive patients with better prognosis( HR=9.646, 95% CI: 1.026-90.700, P=0.047).There were no significant differences in TRM and OS between TCF3: : PBX1-positive and ETV6: : RUNX1-positive patients (all P>0.05).A significant enrichment of PAX5 mutations was detected in TCF3: : PBX1-positive patients.Among the 7 high-risk TCF3: : PBX1-positive patients in a single center, 4 patients had PAX5 mutations, and this proportion was significantly higher than that in other patients ( P<0.001). Conclusions:B-ALL children carrying a TCF3: : PBX1 fusion gene have a high remission rate and good long-term prognosis after intensive chemotherapy.It is suggesting that TCF3: : PBX1-positive B-ALL patients should be rated at intermediate risk to receive intensive chemotherapy.

Objective:Endoplasmic reticulum stress(ERS)was used as the research emphasis to further investigate the mechanisms of apoptosis of FLT3-ITD-mutated leukemia cells and decreased expression of FLT3-ITD mutated protein induced by all-trans retinoic acid(ATRA).Methods:FLT3-ITD-mutated leukemia cell lines(MV4-11 and MOLM13)were treated with ATRA. Flow cytometry was conducted to assess cell apoptosis. Real-time fluorescent quantitative PCR(RT-qPCR)and Western blot were used to detect the expression of ERS-related and autophagy-related genes and protein, respectively.Results:A low-dose ATRA further increased FLT3-ITD cells and ERS levels. ATRA acted on the ERS-related PERK/eif2ɑ signaling pathway and continued to increase the ERS of FLT3-ITD cells, resulting in an upregulation of apoptotic gene CHOP expression. After the treatment with ATRA, FLT3-ITD protein in FLT3-ITD cells was decreased. Of the two main ERS-related protein degradation pathways, ER-associated degradation(ERAD)and ER-activated autophagy(ERAA), the expression of ERAD-related protein ATF6 in FLT3-ITD cells was not significantly changed on ATRA, whereas the expression of ERAA-related proteins Atg7 and Atg5 were significantly increased.Conclusions:ATRA further raises the ERS level of FLT3-ITD cells continuously by activating the ERS-related PERK/eif2ɑ signal pathway and induces FLT3-ITD protein autophagy degradation through ERAA pathway, which induces apoptosis of FLT3-ITD-mutated leukemia cells. These results provide preliminary evidence on the use of ATRA in the treatment of refractory leukemia with FLT3-ITD.

Objective To explore the effect of Flavokawain B on the proliferation and apoptosis of acute T lymphoblastic leukemia(T -ALL)cells and its preliminary mechanism.Methods After the T -ALL cell lines CEM-C7(sensitive to glucocorticoids)and MOLT -4(resistant to glucocorticoids)cells were treated with different concentrations of Flavokawain B,the influence of Flavokawain B on the growth rate and doubling time of CEM-C7 and MOLT -4 cells was observed by 3 -(4,5 -dimethylthiazol -2 -yl)-5 -(3 -carboxymethoxyphenyl)-2 -(4 -sulfophenyl)-2H -tetrazolium(MTS)assay,and apoptosis was analyzed by using flow cytometry.Furthermore,Wes-tern blot assay was used to detect the expressions of Bim,Bcl -2 and cleaved Caspase -9.At last,the expressions of Bim and Bcl -2 in clinical T -ALL patient samples were also detected by using Western blot assay.Results MTS as-say showed that Flavokawain B significantly inhibited the cellular proliferation of T -ALL cell lines in a dose and time dependent manner(P <0.01 ).Flow cytometry findings revealed that Flavokawain B significantly induced the apoptosis of T -ALL cells in a dose -dependent manner(P <0.001 ).Western blot results indicated that Flavokawain B in-creased the expression of Bim and cleaved Caspase -9,and decreased the expression of Bcl -2 in T -ALL cell lines, which increased Bim and decreased Bcl -2 in clinical T -ALL patients samples,both in a dose -dependent manner. Conclusions Flavokawain B can inhibit the proliferation and induce the apoptosis of T -ALL cells by up -regulating the expression of Bim and down -regulating the expression of Bcl -2 and activating Caspase -9,whether resistant to glu-cocorticoids or not.