FOXO3 polymorphisms influence the risk and prognosis of rhabdomyosarcoma in children.

Background: Rhabdomyosarcoma(RMS) is the most common soft tissue sarcoma in children and single nucleotide polymorphisms(SNPs) in certain genes influence risk of RMS. Although FOXO3 had been reported in multiple cancers including RMS, the role of FOXO3 polymorphisms in RMS remains unclear. In this case-control study, we evaluated the association of FOXO3 SNPs with RMS risk and prognosis in children. Methods: Four FOXO3 SNPs(rs17069665 A>G, rs4946936 T>C, rs4945816 C>T and rs9400241 C>A) were genotyped in 110 RMS cases and 359 controls. The associations between FOXO3 polymorphisms and RMS risk were determined by odds ratios(ORs) with 95% confidence intervals(CIs). The associations of rs17069665 and rs4946936 with overall survival in RMS children were estimated using the Kaplan-Meier method and log-rank test. Functional analysis in silico was performed to estimate the probability that rs17069665 and rs4946936 might influence the regulation of FOXO3. Results: We found that rs17069665 (GG vs. AA+AG, adjusted OR=2.96; 95%CI [1.10-3.32]; P=0.010) and rs4946936 (TC+CC vs. TT, adjusted OR=0.48; 95%CI [0.25-0.90]; P=0.023) were related to the increased and decreased RMS risk, respectively. Besides, rs17069665(P<0.001) and rs4946936(P<0.001) were associated with decreased and increased overall survival in RMS patients, respectively. Functional analysis showed that rs17069665 and rs4946936 might influence the transcription and expression of FOXO3 via altering the bindings to MYC, CTCF, and/or RELA. Conclusions: This study revealed that FOXO3 polymorphisms influence the RMS susceptibility and prognosis in children, and might altered the expression of FOXO3. FOXO3 polymorphism was suggested as a biomarker for RMS susceptibility and prognosis.

Gene polymorphisms of METTL5 and METTL16 are related to epithelial ovarian cancer risk in South China: A three-center case-control study.

Background: The potential relation of methyltransferase-like gene polymorphisms and epithelial ovarian cancer (EOC) remains unclear. Methods: Five SNPs (METTL5 rs3769767 A>G, METTL16 rs1056321 T>C, METTL5 rs10190853 G>A, METTL5 rs3769768 G>A and METTL16 rs11869256 A>G) of methyltransferase-like genes was selected trough NCBI dbSNP database. Two hundred and eighty-eight cases and 361 controls were enrolled from three hospitals in South China to conduct the case-control study. Genomic DNA was abstracted from peripheral blood and genotyped through a TapMan assay. Stratified analysis was conducted to explore the association of rs10190853, rs3769768, rs11869256 genotype and EOC susceptibility. The combination analysis was adopted to evaluate the relation between inferred haplotypes of the METTL5, METTL16 genes and EOC risk. Multifactor dimensionality reduction (MDR) analysis was performed to verify the interaction of SNPs. Results: Among the five analyzed SNPs, METTL5 rs3769768 AA exhibited a significant association with increased EOC risk, while METTL5 rs10190853 GA, METTL16 rs11869256 GA was certified to decrease the susceptibility of EOC. The stratified analysis further revealed the harmful effect of METTL5 rs3769768 AA in EOC patients. On the contrary, METTL16 rs11869256 AG/GG and METTL5 rs10190853 AA showed the reduced risk of EOC in patients of specific subgroups. Combination analysis identified that haplotypes AAA highly connected with reduced risk of EOC. MDR analysis revealed that these SNPs existed no specific interactions. Conclusion: METTL5 rs3769768 was related to increased risk of EOC. METTL5 rs10190853 and METTL16 rs11869256 decreased the susceptibility in EOC. METTL5 and METTL16 could be potential target of molecular therapy and prognosis markers.

METTL3-Mediated LINC00475 Alternative Splicing Promotes Glioma Progression by Inducing Mitochondrial Fission.

Mitochondrial fission promotes glioma progression. The function and regulation mechanisms of lncRNAs in glioma mitochondrial fission are unclear. The expression of LINC00475 and its correlation with clinical parameters in glioma were analyzed using bioinformatics. Then, in vitro and in vivo assays were performed to explore the function of spliced variant LINC00475 (LINC00475-S) in gliomas. To explore the mechanisms, RNA-seq, MeRIP, RIP, pulldown-IP, dCas9-ALKBH5 editing system, LC/MS, and Western blotting were utilized. LINC00475 was confirmed to be overexpressed and with higher frequencies of AS events in gliomas compared to normal brain tissue and was associated with worse prognosis. In vitro and animal tumor formation experiments demonstrated that the effect of LINC00475-S on proliferation, metastasis, autophagy, and mitochondrial fission of glioma cells was significantly stronger than that of LINC00475. Mechanistically, METTL3 induced the generation of LINC00475-S by splicing LINC00475 through m6A modification and subsequently promotes mitochondrial fission in glioma cells by inhibiting the expression of MIF. Pull-down combined LC/MS and RIP assays identified that the m6A recognition protein HNRNPH1 bound to LINC00475 within GYR and GY domains and promoted LINC00475 splicing. METTL3 facilitated HNRNPH1 binding to LINC00475 in an m6A-dependent manner, thereby inducing generation of LINC00475-S. METTL3 facilitated HNRNPH1-mediated AS of LINC00475, which promoted glioma progression by inducing mitochondrial fission. Targeting AS of LINC00475 and m6A editing could serve as a therapeutic strategy against gliomas.

IKZF3 polymorphisms contribute to the increased risk of acute lymphoblastic leukemia in children.

BACKGROUND: Acute lymphoblastic leukemia (ALL) is the most common cancer in children. IKZF3 (IKAROS family zinc finger 3) is a hematopoietic-specific transcription factor, and it has been validated that it is involved in leukemia. However, the role of IKZF3 single-nucleotide polymorphisms (SNPs) remains unclear. In this case-control study, the authors investigated the association of IKZF3 SNPs with ALL in children. METHODS: Six IKZF3 reference SNPs (rs9635726, rs2060941, rs907092, rs12946510, rs1453559, and rs62066988) were genotyped in 692 patients who had ALL (cases) and in 926 controls. The associations between IKZF3 polymorphisms and ALL risk were determined using odds ratios (ORs) and 95% confidence intervals (CIs). The associations of rs9635726 and rs2060941 with the risk of ALL were further estimated by using false-positive report probability (FPRP) analysis. Functional analysis in silico was performed to evaluate the probability that rs9635726 and rs2060941 might influence the regulation of IKZF3. RESULTS: The authors observed that rs9635726C>T (adjusted OR, 1.49; 95% CI, 1.06-2.11; p = .023) and rs2060941G>T (adjusted OR, 1.51; 95% CI, 1.24-1.84; p = .001) were related to and increased risk of ALL in the recessive and dominant models, respectively. Furthermore, the associations of both rs9635726 (FPRP = .177) and rs2060941 (FPRP < .001) with ALL were noteworthy in the FPRP analysis. Functional analysis indicated that rs9635726 and rs2060941 might repress the transcription of IKZF3 by disrupting its binding to MLLT1, TAF1, POLR2A, and/or RAD21. CONCLUSIONS: This study revealed that IKZF3 polymorphisms were associated with increased ALL susceptibility in children and might influence the expression of IKZF3 by disrupting its binding to MLLT1, TAF1, POLR2A, and/or RAD21. IKZF3 polymorphisms were suggested as a biomarker for childhood ALL.

PIWIL1 gene polymorphism and pediatric acute lymphoblastic leukemia relapse susceptibility among Chinese children: a five-center case-control study.

Objective: PIWIL1 polymorphisms' role in pediatric acute lymphoblastic leukemia (ALL) relapse susceptibility remains undiscovered. Methods: A case-control designed and multiple logistic regression model was performed to evaluate the overall risk of pediatric ALL and five single-nucleotide polymorphisms (SNPs) of PIWIL1 gene (rs35997018 C>T, rs1106042 A>G, rs7957349 C>G, rs10773771 C>T, and rs10848087 A>G) in 785 cases and 1,323 controls, which were genotyped by TaqMan assay. The odds ratio (OR) and its 95% confidence interval (CI) were used to estimate the relationship. Stratified analysis was used to investigate the correlation of rs1106042 and rs10773771 genotypes and pediatric ALL relapse susceptibility in terms of age, sex, number of white blood cells (WBC), immunophenotyping, gene fusion type, karyotype, primitive/naïve lymphocytes, and minimal residual disease (MRD) in bone marrow. Finally, the haplotype analysis was performed to appraise the relationship between inferred haplotypes of PIWIL1 and pediatric ALL risk. Results: Among the five analyzed SNPs, rs1106042 A>G was related to increased ALL risk, and rs10773771 C>T was related to decreased ALL risk. Compared to the GG genotype, the rs1106042 GA/AA had a deleterious effect on children of age <120 months, who were female and male, had high or average number of WBC, pro-B ALL, pre-B ALL, T-ALL, low- and middle-risk ALL, E2A-PBX fusion gene, non-gene fusion, abnormal diploid, high hyperdiploid, hypodiploid, and normal diploid. Moreover, rs1106042 A>G harmfully affected primitive/naïve lymphocytes and MRD on days 15-19, day 33, and week 12. On the contrary, rs10773771 TC/CC exhibited a protective effect on ALL children with the TEL-AML fusion gene. Haplotype analysis demonstrated that haplotypes CAGT, TACC, TACT, and TAGT were significantly associated with increased pediatric ALL relapse susceptibility. Conclusion: PIWIL1 rs1106042 A>G was related to increased ALL risk, and rs10773771 C>T was linked to decreased ALL risk in eastern Chinese children. Rs1106042 GA/AA may predict poor prognosis.

Diagnostic Values of METTL1-Related Genes and Immune Characteristics in Systemic Lupus Erythematosus.

Purpose: Methyltransferase like 1 (METTL1) regulates epitranscriptomes via the m7G modification in mammalian mRNA and microRNA. Systemic lupus erythematosus (SLE) is caused by abnormal immune reactivity and has diverse clinical manifestations. RNA methylation as a mechanism to regulate gene expression is widely implicated in immune regulation. However, the role of m7G in immune response of SLE has not been extensively studied. Patients and Methods: Expression of METTL1 was identified in the public dataset GSE122459 and validated in an independent cohort of SLE patients. We investigated the association between METTL1-expression and clinical manifestations of SLE. Subsequently, differentially expressed genes (DEG) that were correlated with METTL1-expression in GSE122459 were used for functional enrichment analysis. The correlation between infiltrating immune cells and METTL1, as well as candidate biomarkers identified to be correlated with either METTL1 or immune cell infiltration were assessed by single-sample GSEA. Potential mechanisms were explored with Gene ontology and KEGG pathway enrichment. Diagnostic performances of candidate biomarkers in SLE were analyzed. Results: The mRNA and protein expression of METTL1 in SLE patients were significantly decreased in both datasets. METTL1-coexpressed DEGs were enriched in several key immune-related pathways. Activated CD8 T cells, activated CD4 T cells, memory B cells and type 2 helper T cells were different between patients with high and low METTL1 expression. Further, activated CD8 T-cells, activated CD4 T-cells, memory B-cells were correlated with METTL1. The genes of LAMP3, CD83, PDCD1LG2, IGKVD3D-20, IGKV5-2, IGKV2D-30, IGLV3-19 and IGLV4-60 were identified as candidate targets that were correlated with immune cell proportion. Moreover, LAMP3, CD83, and PDCD1LG2 expression were of diagnostic value in SLE as indicated by ROC analysis. Conclusion: Our findings suggested that METTL1 and its candidate targets LAMP3, CD83, PDCD1LG2 may be used for diagnosing SLE and could be explored for developing targeted molecular therapy for SLE.

Genome-wide analysis revealed the dysregulation of RNA binding protein-correlated alternative splicing events in myocardial ischemia reperfusion injury.

BACKGROUND: Myocardial ischemia reperfusion injury (MIRI), the tissue damage which is caused by the returning of blood supply to tissue after a period of ischemia, greatly reduces the therapeutic effect of treatment of myocardial infarction. But the underlying functional mechanisms of MIRI are still unclear. METHODS: We constructed mouse models of MIRI, extracted injured and healthy myocardial tissues, and performed transcriptome sequencing experiments (RNA-seq) to systematically investigate the dysregulated transcriptome of MIRI, especially the alternative splicing (AS) regulation and RNA binding proteins (RBPs). Selected RBPs and MIRI-associated AS events were then validated by RT-qPCR experiments. RESULTS: The differentially expressed gene (DEG) analyses indicated that transcriptome profiles were changed by MIRI and that DEGs' enriched functions were consistent with MIRI's dysregulated pathways. Furthermore, the AS profile was synergistically regulated and showed clear differences between the mouse model and the healthy samples. The exon skipping events significantly increased in MIRI model samples, while the opposite cassette exon events significantly decreased. According to the functional analysis, regulated alternative splicing genes (RASGs) were enriched in protein transport, cell division /cell cycle, RNA splicing, and endocytosis pathways, which were associated with the development of MIRI. Meanwhile, 493 differentially expressed RBPs (DE RBPs) were detected, most of which were correlated with the changed ratios of AS events. In addition, nine DE RBP genes were validated, including Eif5, Pdia6, Tagln2, Vasp, Zfp36l2, Grsf1, Idh2, Ndrg2, and Uqcrc1. These nine DE RBPs were correlated with RASGs enriched in translation process, cell growth and division, and endocytosis pathways, highly consistent with the functions of all RASGs. Finally, we validated the AS ratio changes of five regulated alternative splicing events (RASEs) derived from important regulatory genes, including Mtmr3, Cdc42, Cd47, Fbln2, Vegfa, and Fhl2. CONCLUSION: Our study emphasized the critical roles of the dysregulated AS profiles in MIRI development, investigated the potential functions of MIRI-associated RASGs, and identified regulatory RBPs involved in AS regulation. We propose that the identified RASEs and RBPs could serve as important regulators and potential therapeutic targets in MIRI treatment in the future.

TFRC-RNA interactions show the regulation of gene expression and alternative splicing associated with IgAN in human renal tubule mesangial cells.

Introduction: IgA nephropathy (IgAN) is the most common primary glomerular disease (PGD) which could progress to renal failure and is characterized by aberrant IgA immune complex deposition. Transferrin receptor1 (TFRC), an IgA receptor, is a potential RNA binding protein (RBP) which regulates expression of genes positively associated with the cell cycle and proliferation and is involved in IgAN. Molecular mechanisms by which TFRC affects IgAN development remain unclear. Methods: In this study, TFRC was overexpressed in human renal tubular mesangial cells (HRMCs) and RNA-sequencing (RNA-seq) and improved RNA immunoprecipitation sequencing (iRIP-seq) were performed. The aim was to identify potential RNA targets of TFRC at transcriptional and alternative splicing (AS) levels. Results: TFRC-regulated AS genes were enriched in mRNA splicing and DNA repair, consistent with global changes due to TFRC overexpression (TFRC-OE). Expression of TFRC-regulated genes potentially associated with IgAN, including CENPH, FOXM1, KIFC1, TOP2A, FABP4, ID1, KIF20A, ATF3, H19, IRF7, and H1-2, and with AS, CYGB, MCM7 and HNRNPH1, were investigated by RT-qPCR and iRIP-seq data analyzed to identify TFRC-bound RNA targets. RCC1 and RPPH1 were found to be TFRC-bound RNA targets involved in cell proliferation. Discussion: In conclusion, molecular TFRC targets were identified in HRMCs and TFRC found to regulate gene transcription and AS. TFRC is considered to have potential as a clinical therapeutic target.

Establishing artificial gene connections through RNA displacement-assembly-controlled CRISPR/Cas9 function.

Construction of synthetic circuits that can reprogram genetic networks and signal pathways is a long-term goal for manipulation of biosystems. However, it is still highly challenging to build artificial genetic communications among endogenous RNA species due to their sequence independence and structural diversities. Here we report an RNA-based synthetic circuit that can establish regulatory linkages between expression of endogenous genes in both Escherichiacoli and mammalian cells. This design employs a displacement-assembly approach to modulate the activity of guide RNA for function control of CRISPR/Cas9. Our experiments demonstrate the great effectiveness of this RNA circuit for building artificial connections between expression of originally unrelated genes. Both exogenous and naturally occurring RNAs, including small/microRNAs and long mRNAs, are capable of controlling expression of another endogenous gene through this approach. Moreover, an artificial signal pathway inside mammalian cells is also successfully established to control cell apoptosis through our designed synthetic circuit. This study provides a general strategy for constructing synthetic RNA circuits, which can introduce artificial connections into the genetic networks of mammalian cells and alter the cellular phenotypes.

ADAR1 polymorphisms contribute to increased susceptibility in pediatric acute lymphoblastic leukemia.

Adenosine deaminase acting on RNA1 (ADAR1), catalyzing post-transcriptional adenosine-to-inosine RNA editing, promotes cancer progression and therapeutic resistance. However, very little is known about the association of ADAR1 variants with acute lymphoblastic leukemia (ALL). Here we first explored the potential association of three polymorphisms (rs9616, rs2229857, and rs1127313) of ADAR1 with susceptibility in Chinese children ALL, then functionally characterized ADAR1 in ALL. Our results demonstrated that rs9616 T and rs2229857 T were associated with increased expression of ADAR1 mRNA and higher risk to ALL. Of note, a stronger risk effect of rs2229857 T genotypes was found among relapse children. Furthermore, ADAR1 knockdown specifically inhibited proliferation and promoted apoptosis in ALL cells. These findings give insights into a mechanism by which the risk variant at rs9616 and rs2229857 modulate ADAR1 expression and confers a predisposition and relapse risk to ALL, and representing a potential novel biomarker for pediatric ALL.

New association between splicing factor-coding gene polymorphisms and the risk of acute lymphoblastic leukemia in southern Chinese children: A five-center case-control study.

BACKGROUND: The role of splicing factor-coding gene polymorphisms in pediatric acute lymphoblastic leukemia (ALL) susceptibility is still unclear. METHODS: A case-control designed model was used to estimate the overall risk of pediatric ALL and five single nucleotide polymorphisms (SNPs) of splicing factor-coding genes in 808 cases and 1,340 controls, which were genotyped using a TaqMan assay. Stratified analysis was performed to explore the association of rs2233911 genotype and pediatric ALL susceptibility. The influence of splicing factor arginine/serine-rich 1 (SFRS1) polymorphisms on the sensitivity to different chemotherapeutic regimens based on minimal residual disease (MRD) levels was analyzed. The haplotype analysis was adopted to evaluate the association between inferred haplotypes of the splicing factor-coding genes and pediatric ALL risk. RESULTS: Among the five analyzed SNPs, SFRS1 rs2233911 AG/GG exhibited a significant association with increased pediatric ALL risk. The stratified analysis further identified the harmful effect of SFRS1 rs2233911 AG/GG in specific subgroups. Moreover, rs2233911 AG/GG had a protective effect on MRD in marrow of ≥0.01%  12 weeks of Chinese Children Cancer Group chemotherapeutics, but provided a harmful effect on MRD in the marrow of ≥0.01% at days 15-19 of the South China Children Leukemia Group chemotherapeutics. Haplotype analysis of these five SNPs yielded haplotypes ACGCC and ACGTC significantly correlating with increased pediatric ALL susceptibility. On the contrary, haplotypes GCATG and GTACC were linked with remarkably decreased pediatric ALL risk. CONCLUSION: SFRS1 gene polymorphism was associated with increased pediatric ALL risk and indicated that rs2233911 AG/GG might be a potential biomarker for choosing chemotherapeutics.

[Expression of ROBO3 and Its Effect on Cell Proliferation and Apoptosis in Pediatric Patients with Acute Myeloid Leukemia].

OBJECTIVE: To investigate the expression of ROBO3 in pediatric AML patients and explore its function on cell proliferation and apoptosis. METHODS: The expression of ROBO3 in pediatric AML patients at different treatment stage was detected by real-time quantitative polymerase chain reaction (RT-qPCR). The relationship between the expression of ROBO3 and clinic pathological characteristics in newly diagnosed pediatric AML patients was analyzed. Moreover, the effects of ROBO3 on the proliferation and apoptosis of AML cell lines HL-60 and THP-1 were estimated by using CCK-8 and flow cytometry after transfection with ROBO3 siRNA. RESULTS: It was found that ROBO3 expression was significantly increased in most of newly diagnosed pediatric AML patients, especially in non-M3 subtype, younger patients (<10 years old), and high risk group, compared to corresponding controls. Furthermore, the expression level of ROBO3 was sharply decreased in patients who achieved complete remission. Targeting ROBO3 significantly inhibited AML cell proliferation, as well as increased apoptosis by ROBO3 siRNA transfection in vitro. CONCLUSION: ROBO3 is differentially expressed within distinct subtypes of the pediatric AML patients, which suggested that ROBO3 may be a potential biomarker and a new therapeutic target for pediatric AML.

Mesenchymal stromal cell treatment improves outcomes in children with pneumonia post-hematopoietic stem cell transplantation: a retrospective cohort study.

BACKGROUND: Hematopoietic stem cell transplantation (HSCT) is a standard therapy strategy for most malignant disorders in children. However, transplant-related pneumonia remains a major therapy challenge and mesenchymal stromal cells (MSCs) are rarely reported in HSCT-related pneumonia. The aim of our study was to assess the efficacy of MSC for HSCT-related pneumonia in children. METHODS: We retrospectively retrieved HSCT-related (severe and non-severe) pneumonia cases (aged < 18 years), which underwent MSC treatment (MSC group) or non-MSC treatment (non-MSC group) in Guangzhou Women and Children's Medical Center, from December 2017 to December 2019. We investigated outcomes of the two different treatments among severe cases and non-severe cases, respectively. The primary endpoints were differences in overall cure rate and time to cure between MSC and non-MSC groups. The secondary endpoints were 180-day overall survival and cumulative cure rate. RESULTS: Finally, 31 severe pneumonia cases (16 in MSC group, 15 in non-MSC group) and 76 non-severe cases (31 in MSC group, 45 in non-MSC group) were enrolled in this study. Among severe pneumonia cases, overall cure rate in MSC group was significant higher than that in non-MSC group (12[75.0%] vs. 5[33.3%]; OR = 6.00, 95% CI [1.26-28.5]; p = 0.020); the time (days) to cure in MSC group was dramatically reduced compared with that in non-MSC group (36 [19-52] vs. 62 [42-81]; OR = 0.32, 95% CI [0.12-0.88]; p = 0.009); the 180-day overall survival in MSC group was better than that in non-MSC group (74.5% [45.4-89.6] vs. 33.3% [12.2-56.4]; p = 0.013). Among non-severe pneumonia cases, the time (days) to cure in MSC group was notably decreased compared with that in non-MSC group (28 [24-31] vs. 33 [26-39]; OR = 0.31, 95% CI [0.18-0.56]; p = 0.003). Compared with non-MSC group, MSC-treated patients achieved significant improvements of cumulative cure rate not only in severe pneumonia cases (p = 0.027), but also in non-severe cases (p < 0.001). CONCLUSIONS: This study revealed that MSC treatment could contribute to improving outcomes in children with pneumonia post-HSCT, especially in severe cases. These findings suggest MSC treatment as a promising therapy for HSCT-related pneumonia in children.

Sevoflurane Induces Ferroptosis of Glioma Cells Through Activating the ATF4-CHAC1 Pathway.

Objective: To clarify the function and mechanisms of sevoflurane (Sev) on ferroptosis in glioma cells. Methods: Different concentrations of Sev were used to treat glioma cells U87 and U251. Ferroptosis inducer Erastin was used to incubate glioma cells combined with Sev and ATF4 siRNA transfection treatment. CCK-8 assay and colorimetric assay were performed to analyze cell viability and Fe+ concentration, respectively. The releases of reactive oxygen species (ROS) were determined by flow cytometry analysis. Transcriptional sequencing was used to screen the differential genes affected by Sev in U251 cells. The mRNA and protein expression of ferroptosis-associated genes was detected by qRT-PCR and Western blotting. Results: Sev could suppress cell viability, increase ROS levels and Fe+ concentration, downregulate the protein expression levels of GPX4, and upregulate transferrin, ferritin, and Beclin-1 in a dose-dependent manner in U87 and U251 cells. The expression of ferroptosis and mitophagy-related gene activating transcription factor 4 (ATF4) was identified to be enhanced by Sev analyzed by transcriptional sequencing. ChaC glutathione-specific gamma-glutamylcyclotransferase 1 (CHAC1), which is involved in ferroptosis, is a downstream gene of ATF4. Inhibition of ATF4 could interrupt the expression of CHAC1 induced by Sev in U87 and U251 cells. Ferroptosis inducer Erastin treatment obviously inhibited the cell viability, elevated the Fe2+ concentration, and promoted ROS generation in U87 and U251 cells. The protein level of ATF4 and CHAC1 was increased in Erastin-treated U87 and U251 cells. Moreover, the interruption of Sev-induced ferroptosis and CHAC1 activating induced by ATF4 suppression could be reversed by Erastin. Conclusions: In summary, this study suggested that Sev exposure-induced ferroptosis by the ATF4-CHAC1 pathway in glioma cells.

Genetic variants in m5C modification core genes are associated with the risk of Chinese pediatric acute lymphoblastic leukemia: A five-center case-control study.

Objective: To explore the functions of the polymorphisms in 5-methylcytosine (m5C) modification-related coding genes on the susceptibility of pediatric acute lymphoblastic leukemia (ALL). Methods: Case-control study and multinomial logistic regression analysis were performed to construct models to evaluate the susceptibility of pediatric ALL. The relationship between five functional SNPs in m5C modification-coding genes and pediatric ALL risk was analyzed. Genotyping of 808 cases and 1,340 healthy samples from South China was identified using a TaqMan assay; odds ratios (ORs) and 95% confidence intervals (CIs) were calculated to estimate the relationship between the five selected SNPs and pediatric ALL susceptibility. Results: Among the five analyzed SNPs, NOL1 rs3764909 and NSUN4 rs10252 variants significantly increased the susceptibility of pediatric ALL, while NSUN3 rs7653521, NSUN5 rs1880948, and NSUN6 rs3740102 variants were not associated with the risk of ALL. Stratification analyses demonstrated that NOL1 rs3764909 C>A exhibited a significant association with increased pediatric ALL risk in subgroups of common B ALL, pre-B ALL, T-cell ALL, low and middle risk, other gene fusion types, non-gene fusion, hypodiploid, normal diploid, primitive lymphocytes in marrow < 5% on week 12, and minimal residual disease (MRD) <0.01% on week 12 after induced therapy; NSUN4 rs10252 G>A was related to increased risk of ALL children in subgroups of age ≥ 120 months, normal white blood cell (WBC) number, middle risk, non-gene fusion, MRD ≥ 0.01 on days 15-19, and primitive lymphocytes in marrow < 5% on day 33 after induced therapy. Compared with the reference haplotype CAGTA, children who harbored haplotypes CCGTG and ACATA were remarkably related to increased ALL susceptibility. rs3764909 and rs10252 varieties of alleles were not associated with MRD levels after the selected chemotherapeutics. Conclusions: In conclusion, NOL1 rs3764909 and NSUN4 rs10252 variants were enhanced by pediatric ALL risk and were suggested to be potential biomarkers for pediatric ALL.

Genetic Variants in METTL14 are Associated with the Risk of Acute Lymphoblastic Leukemia in Southern Chinese Children: A Five-Center Case-Control Study.

BACKGROUND/AIM: Acute lymphoblastic leukemia (ALL) is the most common form of pediatric cancer. METTL14, an N6-methyladenosine (m6A) modification protein, plays several roles in cancer development and is involved in the pathogenesis of various types of cancers. However, the role of METTL14 gene single nucleotide polymorphisms (SNPs) in pediatric ALL susceptibility remains to be investigated. METHODS: A case-control design and multinomial logistic regression were used to develop models to estimate the overall risk for pediatric ALL and three METTL14 gene SNPs (rs298982 G/A, rs298981 A/G and rs1064034 T/A) in 808 cases and 1340 controls, which were genotyped using a TaqMan assay. The associations were estimated by odds ratios (ORs) with their 95% confidence intervals (CIs). Furthermore, stratified analysis was performed to explore associations of rs298982 and rs1064034 with pediatric ALL susceptibility in terms of age, sex, immunophenotype, minimal residual disease (MRD), and other clinical characteristics. RESULTS: Among the three analyzed SNPs, rs298982 G/A and rs1064034 T/A exhibited a significant association with decreased childhood ALL risk, while rs298981 A/G exhibited no difference. In stratified analysis, rs298982 GA/AA and rs1064034 TA/AA had a protective effect in children <120 months of age and males, common B ALL, TEL-AML, non gene fusion, normal diploid, and high WBC. However, the rs1064034 TA/AA genotype was associated with an increased risk of mixed immunophenotyping. Compared with the reference haplotype GAT, haplotypes CAA, CGT and CGA were significantly associated with elevated ALL risk, while haplotype GGT was significantly associated decreased ALL risk. Moreover, subjects carrying rs298982 A or rs1064034 A exhibited less minimal MRD after induced chemotherapy. Functional annotations revealed that METTL14 gene SNPs rs298982 G/A and rs1064034 T/A could be potential functional variants. CONCLUSION: In conclusion, METTL14 gene polymorphisms influence the risk of ALL in southern Chinese children and might be potential biomarkers for pediatric ALL susceptibility and chemotherapeutics.

CircRNF220, not its linear cognate gene RNF220, regulates cell growth and is associated with relapse in pediatric acute myeloid leukemia.

BACKGROUND: Circular RNAs (circRNAs) constitute a family of transcripts with unique structures and have been confirmed to be critical in tumorigenesis and to be potential biomarkers or therapeutic targets. However, only a few circRNAs have been functionally characterized in pediatric acute myeloid leukemia (AML). METHODS: Here, we investigated the expression pattern of circRNAs in pediatric AML using a circRNA microarray. The characteristics, potential diagnostic value, and prognostic significance of circRNF220 were evaluated. A series of functional experiments were performed to investigate the role of circRNF220 in primary pediatric AML cells. Then we investigated the aberrant transcriptional networks regulated by circRNF220 in primary AML cells by RNA-seq. Furthermore, biotin RNA pulldown assays were implemented to verify the relationship between circRNF220 and miR-30a. RESULTS: We identified a circRNA, circRNF220, which was specifically abundant in and accumulated in the peripheral blood and bone marrow of pediatric patients with AML. It could distinguish AML from ALL and other hematological malignancies with high sensitivity and specificity. Significantly, circRNF220 expression independently predicted prognosis, while high expression of circRNF220 was an unfavorable prognostic marker for relapse. Furthermore, we characterized the function of circRNF220 and found that circRNF220 knockdown specifically inhibited proliferation and promoted apoptosis in AML cell lines and primary cells. Mechanistically, circRNF220 may act as an endogenous sponge of miR-30a to sequester miR-30a and inhibit its activity, which increases the expression of its targets MYSM1 and IER2 and implicated in AML relapse. CONCLUSIONS: Collectively, these findings demonstrated that circRNF220 could be highly efficient and specific for the accurate diagnosis of pediatric AML, with implications for relapse prediction.

Novel Associations Between METTL3 Gene Polymorphisms and Pediatric Acute Lymphoblastic Leukemia: A Five-Center Case-Control Study.

OBJECTIVE: To reveal the contributing role of METTL3 gene SNPs in pediatric ALL risk. PATIENTS AND METHODS: A total of 808 pediatric ALL cases and 1,340 cancer-free controls from five hospitals in South China were recruited. A case-control study by genotyping three SNPs in the METTL3 gene was conducted. Genomic DNA was abstracted from peripheral blood. Three SNPs (rs1263801 C>G, rs1139130 A>G, and rs1061027 A>C) in the METTL3 gene were chosen to be detected by taqman real-time polymerase chain reaction assay. RESULTS: That rs1263801 C>G, rs1139130 A>G, and rs1061027 A>C polymorphisms were significantly associated with increased pediatric ALL risk was identified. In stratification analyses, it was discovered that rs1263801 CC, rs1061027 AA, and rs1139130 GG carriers were more likely to develop ALL in subgroups of common B-ALL, MLL gene fusion. Rs1263801 CC and rs10610257 AA carriers were more possible to increase the risk of ALL in subgroups of low hyperdiploid, and all of these three SNPs exhibited a trend toward the risk of ALL. All of these three polymorphisms were associated with the primitive/naïve lymphocytes and MRD in marrow after chemotherapy in ALL children. Rs1263801 CC and rs1139130 AA alleles provided a protective effect on MRD ≥0.01% among CCCG-treated children. As for rs1139130, AA alleles provided a protective effect on MRD in marrow ≥0.01% on 33 days and 12 weeks among CCCG-treated children, but provided a risk effect on MRD in the marrow ≥0.01% among SCCLG-treated children. As for rs1263801 CC and rs1139130 AA, these two alleles provided a protective effect on MRD in the marrow ≥0.01% among CCCG-treated children. CONCLUSION: In this study, we revealed that METTL3 gene polymorphisms were associated with increased pediatric ALL risk and indicated that METTL3 gene polymorphisms might be a potential biomarker for choosing ALL chemotherapeutics.

The dietary carcinogen PhIP activates p53-dependent DNA damage response in the colon of CYP1A-humanized mice.

Species differences in the metabolism of xenobiotics by cytochrome P450 are critical in evaluating the use of experimental animals in studying toxic compounds relevant to human diseases. 2-Amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP), which is produced by high-temperature cooking of fish and meat, is activated to become a carcinogen by cytochrome P4501A2 (CYP1A2) through N2 -hydroxylation in humans, but is detoxified by Cyp1a2 through 4'-hydroxylation in mice. CYP1A-humanized (hCYP1A) mice, in which mouse Cyp1a is replaced with human CYP1A, show constitutive human xenobiotic metabolism by hCYP1A, thereby serving as a suitable model for studying PhIP. Previous studies have demonstrated that oral administration of PhIP induces colon tumors in hCYP1A mice; however, these studies used a super-high dose, raising concerns regarding the relevance of the mechanism to human cancer. Herein, we systematically investigated PhIP-induced colon carcinogenesis in hCYP1A mice treated with lower doses. We found that a dose 2000 times lower than that used previously, which is comparable to human daily intake levels, could induce colon tumors, albeit at a lower incidence rate. We further investigated the transcriptome changes in the colon of hCYP1A mice treated with PhIP and identified that PhIP treatment increased the expression of Bax, Btg2, Ccng1, Cdkn1a, and Trp53inp1 and decreased the expression of Igf1 and Ccnd1. Since these genes are key components of the p53-dependent DNA damage response, the altered expression patterns indicated PhIP-induced DNA damage in hCYP1A mice. Together, these results prove that hCYP1A mice are suitable for studying PhIP-induced carcinogenesis and show that PhIP is an important colorectal cancer carcinogen in human diet.

Genetic variants in m6A modification core genes are associated with glioma risk in Chinese children.

Glioma is a highly heritable disease with a strong genetic component. The N6-methyladenosine (m6A) modification core genes play important roles in the context of cancer. However, the effects of polymorphisms in the m6A modification core genes on the risk of pediatric glioma remain undefined. Here, we intended to demonstrate the relationship between 24 functional single-nucleotide polymorphisms (SNPs) in eight m6A modification core genes and glioma risk. Case-control design and multinomial logistic regression were used to develop models to estimate the risk of glioma while accounting for the subtypes of glioma. A total of 171 glioma cases and 228 controls from South China were genotyped using a TaqMan assay. The WTAP rs7766006, YTHDF2 rs3738067, and FTO rs9939609 variants conferred a statistically significant increased risk of glioma, respectively. YTHDC1 rs2293595, YTHDC1 rs3813832, and FTO rs8047395 were associated with a significant inverse association with risk of glioma, respectively. The significant associations were more predominant in stratification analyses of certain subgroups. Functional annotations revealed that WTAP rs7766006 and YTHDF2 rs3738067 could be potential functional variants by increasing expression of WTAP and YTHDF2 mRNA, respectively. Overall, these findings implicate variants in the m6A modification core genes as playing a role in pediatric glioma etiology.