Reduced Proteolipid Protein 2 promotes endoplasmic reticulum stress-related apoptosis and increases drug sensitivity in acute myeloid leukemia.

BACKGROUND: The Proteolipid Protein 2 (PLP2), a protein in the Endoplasmic Reticulum (ER) membrane, has been reported to be highly expressed in various tumors. Previous studies have demonstrated that the reduced PLP2 can induce apoptosis and autophagy through ER stress-related pathways, leading to a decreased proliferation and aggressiveness. However, there is no research literature on the role of PLP2 in Acute Myeloid Leukemia (AML). METHODS: PLP2 expression, clinical data, genetic mutations, and karyotype changes from GEO, TCGA, and timer2.0 databases were analyzed through the R packages. The possible functions and pathways of cells were explored through GO, KEGG, and GSEA enrichment analysis using the clusterProfiler R package. Immuno-infiltration analysis was conducted using the Cibersort algorithm and the Xcell R package. RT-PCR and western blot techniques were employed to identify the PLP2 expression, examine the knockdown effects in THP-1 cells, and assess the expression of genes associated with endoplasmic reticulum stress and apoptosis. Flow cytometry was utilized to determine the apoptosis and survival rates of different groups. RESULTS: PLP2 expression was observed in different subsets of AML and other cancers. Enrichment analyses revealed that PLP2 was involved in various tumor-related biological processes, primarily apoptosis and lysosomal functions. Additionally, PLP2 expression showed a strong association with immune cell infiltration, particularly monocytes. In vitro, the knockdown of PLP2 enhanced endoplasmic reticulum stress-related apoptosis and increased drug sensitivity in THP-1 cells. CONCLUSIONS: PLP2 could be a novel therapeutic target in AML, in addition, PLP2 is a potential endoplasmic reticulum stress regulatory gene in AML.

Allogeneic hematopoietic stem cell transplantation overcome the poor prognosis of patients with IKZF1plus CD20-a very high-risk subtype in B-cell acute lymphoblastic leukemia.

Genetic deletions of IKZF1 (IKZF1del) and IKZF1del plus other mutations (IKZF1plus) have been identified in B-cell acute lymphoblastic leukemia (B-ALL) with a poor prognosis. Herein, we investigated the combination of IKZF1del and CD20 immunotypes in adult patients with B-ALL in the PDT-ALL-2016 cohort. This study cohort consisted of 161 patients with B-ALL with detailed information on IKZF1del and CD20 expression. The independent cohort included 196 patients from the TARGET dataset. IKZF1del was detected in 36.0% of patients with 3-year event-free survival (EFS) of 37.1 ± 6.7% and overall survival (OS) of 51.5 ± 7.3%, compared to IKZF1 wild-type (IKZF1wt) with an EFS 55.3 ± 5.1% (P = 0.011) and OS 74.4 ± 4.5% (P = 0.013), respectively. CD20-positive (CD20+) was associated with inferior EFS compared to the CD20-negative (CD20-) group (P = 0.020). Furthermore, IKZF1del coupled with CD20+, IKZF1del/CD20+, comprised 12.4% of patients with a 3-year EFS of 25.0 ± 9.7%, compared with IKZF1wt/CD20- (P ≤ 0.001) and IKZF1del/CD20- (P = 0.047) groups. Multivariable analyses demonstrated the independence of IKZF1del/CD20+, with the highest predicted hazard ratio for EFS and OS. Furthermore, the prognostic panel of IKZF1del/CD20+ was confirmed in the TARGET cohort. Notably, neither the IKZF1del, CD20+, or IKZF1del/CD20+ groups were identified to have poor outcomes in the cohort of allogeneic hematopoietic stem cell transplantation (n = 81).Collectively, our data define IKZF1del/CD20+ as a very high-risk subtype in B-ALL, and allo-HSCT could abrogate the poor outcome of both IKZF1del and IKZF1del/CD20+ subsets.

Early T-Cell Precursor Leukemia Has a Higher Risk of Induction-Related Infection among T-Cell Acute Lymphoblastic Leukemia in Adult.

BACKGROUND: Infections are an important cause of morbidity and mortality for acute lymphoblastic leukemia (ALL). However, the reports regarding risk factors of induction-related infection are roughly unknown/limited in adult T-ALL during induction chemotherapy. METHODS: We performed a retrospective cohort study for the prevalence and risk predictors of induction-related infection among consecutive T-ALL patients (N = 97) enrolled in a PDT-ALL-LBL clinical trial. Of 97 patients with T-ALL enrolled in the trial, 46 were early T-cell precursor (ETP) ALL and 51 were non-ETP ALL. RESULTS: When compared with non-ETP, ETP ALL subtype was characterized with lower neutrophil count (1.35 × 109/L vs. 8.7 × 109/L, P < 0.001) and lower myeloid percentage in the bone marrow (13.35% vs. 35.31%, P = 0.007). Additionally, ETP ALL had longer neutropenia before diagnosis (P < 0.001), as well as during induction chemotherapy (P < 0.001). Notably, the ETP cohort experienced higher cumulative incidence of clinically documented infections (CDI; 33.33%, P = 0.001), microbiologically documented infections (MDI; 45.24%, P = 0.006), resistant infection (11.9%, P = 0.013), and mixed infection (21.43%, P = 0.003), respectively, than those of the non-ETP cohort. Furthermore, multivariable analysis revealed that T-ALL mixed infection was more likely related to chemotherapy response (OR, 0.025; 95% CI 0.127-0.64; P = 0.012) and identified myeloid percentage as a predictor associated with ETP-ALL mixed infection (OR, 0.915; 95% CI 0.843-0.993; P = 0.033), with ROC-defined cut-off value of 2.24% in ETP cohorts. CONCLUSIONS: Our data for the first time demonstrated that ETP-ALL characterized with impaired myelopoiesis were more susceptible to induction-related infection among T-ALL populations.