Genetic susceptibility in childhood acute lymphoblastic leukemia

Multi-step gene set analysis identified HTR3 family genes involving childhood acute lymphoblastic leukemia susceptibility

In our previous conventional genome-wide association study (GWAS), WWOX was a susceptibility gene associated with acute lymphoblastic leukemia (ALL) development. Nowadays, advancements in genetic association analyses promote an in-depth exploration of ALL genomics. We conducted a two-step enrichment analysis at both gene and pathway levels based on ALL GWAS data including 269 cases and 1039 controls of Chinese descent. The following functional prediction and experiments were used to evaluate the genetic biology of candidate variants and genes. The serotonin-activated cation-selective channel complex gene-set was a potential biological pathway involved in ALL occurrence. Of which, individuals carrying the T allele of rs33940208 exhibited a prominent reduced risk of ALL [odds ratio (OR) = 0.71, 95% confidence interval (CI) = 0.53 to 0.96, P = 2.81 × 10-2], whereas those with the A allele of rs6779545 demonstrated an increased risk (OR = 1.23, 95% CI = 1.01 to 1.51, P = 4.11 × 10-2). Notably, the two variants displayed a better prediction capability when combined, that the risk of developing childhood ALL increased by 131% in subjects with 2-4 risk alleles compared to those with 0-1 risk alleles (Ptrend = 2.05 × 10-3). In addition, the T allele of rs33940208 could reduce HTR3A mRNA level, while the A allele of rs6779545 increased HTR3D mRNA expression. In this study, we identified HTR3A rs33940208 and HTR3D rs6779545 as potential susceptibility loci for ALL in Chinese children. Future validation and functional research will elucidate the underlying molecular processes, refining preventive strategies for this disease.

Potency and efficacy of pharmacological PIP4K2 inhibitors in acute lymphoblastic leukemia

Acute lymphoblastic leukemia (ALL), a complex malignancy, displays varying expression profiles of PIP4K2-related genes in adult patients. While PIP4K2A expression is elevated in ALL bone marrow cells compared to healthy bone marrow cells, PIP4K2B is downregulated, and PIP4K2C remains relatively unchanged. Despite the correlation between increased PIP4K2A expression and increased percentage of peripheral blood blasts, clinical outcomes do not strongly correlate with the expression of these genes. Here we investigated the therapeutic potential of three PIP4K2 inhibitors (THZ-P1-2, a131, and CC260) in ALL cell models. THZ-P1-2 emerges as the most effective inhibitor, inducing cell death and mitochondrial damage while reducing cell viability and metabolism significantly. Comparative analyses highlight the superior efficacy of THZ-P1-2 over a131 and CC260. Notably, THZ-P1-2 uniquely disrupts autophagic flux and inhibits the PI3K/AKT/mTOR pathway, indicating a distinct molecular mechanism. In summary, our findings elucidate the differential expression of PIP4K2-related genes in ALL and underscore the potential role of PIP4K2A in disease pathogenesis. The therapeutic promise of THZ-P1-2 in ALL treatment, along with its distinct effects on cell death mechanisms and signaling pathways, enriches our understanding of PIP4K2's involvement in ALL development and offers targeted therapy prospects.

Polymorphisms of inflammation-related genes and susceptibility to childhood leukemia: evidence from a meta-analysis of 16 published studies

OBJECTIVE

This study was to comprehensively clarify the associations between single nucleotide polymorphisms (SNPs) in inflammatory genes and the susceptibility to childhood leukemia.

METHODS

Eligible articles were collected from the databases of PubMed, EMBASE, Cochrane Library, CNKI and Wan Fang. The pooled odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated to estimate the association strength by using the STATA 15.0 software.

RESULTS

Sixteen studies were enrolled. These studies mainly evaluated SNPs in 13 genes, including C-X-C motif chemokine ligand 12 (CXCL12), toll-like receptor (TLR)-4, TLR6, TLR9, CD14, interleukin (IL)-1β, NLR family pyrin domain containing 3, IL-4, interleukin 4 receptor, IL-10, IL-13, macrophage migration inhibitory factor (MIF) and tumor necrosis factor-α. The meta-analysis indicated that CXCL12 rs1801157 (AG vs GG: OR = 1.99; 95%CI = 1.20-3.30; p = 0.008; AA + AG vs GG: OR = 1.92; 95%CI = 1.18-3.12; p = 0.009), TLR6 rs5743810 (TC vs TT: OR = 0.58; 95%CI = 0.39-0.85; p = 0.005), IL-10 rs1800871 (TC vs CC: OR = 1.19; 95%CI = 1.01-1.41; p = 0.044), rs1800872 (AC vs AA: OR = 1.53; 95%CI = 1.22-1.92; p < 0.001) and MIF rs755622 (CG versus GG: OR = 1.33; 95%CI = 1.07-1.67; p = 0.012) polymorphisms were associated with the risk of childhood leukemia. No significant correlations were found between SNPs in other genes and the childhood leukemia risk. Subgroup analyses of rs1800871 and rs1800872 confirmed the conclusions obtained in their overall meta-analytical processes.

CONCLUSION

CXCL12 rs1801157, TLR6 rs5743810, IL-10 rs1800871, rs1800872 and MIF rs755622 polymorphisms may represent candidate biomarkers for the risk prediction of childhood leukemia.

Association of Genetic Polymorphisms of TERT with Telomere Length in Coke Oven Emissions-Exposed Workers

We explored the association between variations in the telomere maintenance genes and change in telomere length (TL) in workers. The TL of peripheral blood leukocytes from 544 coke oven workers and 238 controls were detected using the Real-time PCR method. Variations in four genes were then detected using the PCR based restriction fragment length polymorphism. The effects of environmental and genetic factors on TL were subsequently analyzed through covariance analysis and a generalized linear model .The TL of subjects with GG genotypes were longer than those with AG genotype in the TERT rs2736098 locus amongst the controls (P = .032). The combined effect of COEs exposure and AG+AA genotypes had a significant effect on TL (P < .001). The interaction between the COEs exposure factor and the rs2736098AG+AA genotypes had a significant effect on the TL (P < .05). The TL in coke oven workers is associated with the interactions between TERT rs2736098 AG+AA and COEs exposure.

Acute lymphoblastic leukemia in children and SALL4 and BMI-1 gene expression

BACKGROUND

Sal-like protein 4 transcription factor (SALL4) and B cell-specific Moloney murine leukemia virus integration site 1 (BMI-1) gene were reported to cause treatment failure and relapse in several malignancies. We aimed to evaluate the prognostic value of SALL4 and BMI-1 in children with acute lymphoblastic leukemia (ALL).

METHODS

This prospective cohort study was carried out on 60 children with ALL as the patient group and 60 age- and sex-matched children as the control group. We evaluated the expression pattern of both SALL4 and BMI-1 genes in the peripheral blood using real-time reverse transcriptase-polymerase chain reaction in children with ALL at initial diagnosis before chemotherapy. We followed up with the patient group for 2 years for relapse or death.

RESULTS

Both SALL4 and BMI-1 were overexpressed in ALL children compared to the control group. Moreover, the expression of SALL4 and BMI-1 in patients with relapse was significantly higher than those with complete remission. The best cut-off of SALL4 and BMI-1 to predict relapse were >2.21 and 0.55 yielding sensitivity of 92.3% and 84.6%, respectively. Patients with overexpression of SALL4 and BMI-1 had significantly shorter overall and disease-free survival.

CONCLUSIONS

SALL4 and BMI-1 could be useful prognostic markers in children with ALL to predict relapse.

Influence of Genetic Variations in miRNA and Genes Encoding Proteins in the miRNA Synthesis Complex on Toxicity of the Treatment of Pediatric B-Cell ALL in the Brazilian Amazon

Acute lymphoblastic leukemia (ALL) is the most common childhood cancer in the world. Single nucleotide variants (SNVs) in miRNA and genes encoding proteins of the miRNA synthesis complex (SC) may affect the processing of drugs used in the treatment of ALL, resulting in treatment-related toxicities (TRTs). We investigated the role of 25 SNVs in microRNA genes and genes encoding proteins of the miRNA SC, in 77 patients treated for ALL-B from the Brazilian Amazon. The 25 SNVs were investigated using the TaqMan^® OpenArray™ Genotyping System. SNVs rs2292832 (MIR149), rs2043556 (MIR605), and rs10505168 (MIR2053) were associated with an increased risk of developing Neurological Toxicity, while rs2505901 (MIR938) was associated with protection from this toxicity. MIR2053 (rs10505168) and MIR323B (rs56103835) were associated with protection from gastrointestinal toxicity, while DROSHA (rs639174) increased the risk of development. The rs2043556 (MIR605) variant was related to protection from infectious toxicity. SNVs rs12904 (MIR200C), rs3746444 (MIR499A), and rs10739971 (MIRLET7A1) were associated with a lower risk for severe hematologic toxicity during ALL treatment. These findings reveal the potential for the use of these genetic variants to understand the development of toxicities related to the treatment of ALL in patients from the Brazilian Amazon region.

Association of Ethnicity, Sex, and Age With Cancer Diagnoses and Health Care Utilization Among Children in Inner Mongolia, China

IMPORTANCE

China is experiencing a sustained increase in childhood cancer. However, whether differences exist in disease burden by ethnicity remains unclear.

OBJECTIVE

To compare differences in cancer diagnoses and health care utilization in Inner Mongolia among children subgrouped by ethnicity (Han vs Mongolian), sex, and age.

DESIGN, SETTING, AND PARTICIPANTS

This retrospective cohort study in Inner Mongolia, China, used data on children aged 0 to 14 years with cancer from the Inner Mongolia Regional Health Information Platform, which comprises the National Basic Medical Insurance database and the Inner Mongolia cause-of-death reporting system, from January 1, 2013, to December 31, 2019. Ethnicities analyzed included Han and Mongolian; patients of other ethnicities were not included in the analysis because of the small sample size. Cancer was broadly defined as a primary malignant tumor or hematologic cancer; benign central nervous system tumors were also included. A 2-year washout period was used to exclude prevalent cases. After diagnosis, the patients were followed up until the date of death or the end of the insured status, whichever came first.

EXPOSURES

Ethnicity (Han vs Mongolian), sex (male vs female), and age (0-4, 5-9, and 10-14 years).

MAIN OUTCOMES AND MEASURES

Crude incidence, 5-year prevalence, and survival rates at 1 year and 3 years after diagnosis; health care utilization, represented by medical costs during the first year and first 3 years after diagnosis; and hospital attendance with level (tertiary vs secondary and lower-level hospitals) and location of each unique visit.

RESULTS

From 2013 to 2019, 1 106 684 (2013), 1 330 242 (2014), 1 763 746 (2015), 2 400 343 (2016), 2 245 963 (2017), 2 901 088 (2018), and 2 996 580 (2019) children aged 0 to 14 years were registered in the NBMI database. Among the 2 996 580 children enrolled in 2019, the mean (SD) age was 6.8 (4.3) years, of whom 1 572 096 (52.5%) were male, 2 572 091 (85.8%) were Han, and 369 400 (12.3%) were Mongolian. A total of 1910 patients with cancer were identified (1048 were male [54.9%]; 1559 were Han [81.6%], and 300 were Mongolian [15.7%]). There were 764 hematologic cancers (40.0%) and 1146 solid tumors (60.0%). The overall crude incidence of cancer from 2015 to 2019 was 129.85 per million children (95% CI, 123.63-136.06), with a higher incidence among Mongolian than among Han children (155.12 [95% CI, 136.81-173.43] vs 134.39 [95% CI, 127.46-141.32]). The 5-year prevalence was 428.97 per million (95% CI, 405.52-452.42) in 2020, with a higher prevalence among Mongolian than among Han children (568.49 [95% CI, 91.62-645.36] vs 404.34 [95% CI, 379.77-428.91]). The combined 1-year (2015-2019) and 3-year (2015-2017) survival rates were 72.5% (95% CI, 67.5%-77.5%) and 66.8% (95% CI, 61.6%-71.9%), respectively. The 1-year (median [IQR], $1991 [$912-$10 181] vs $3991 [$1171-$15 425]) and 3-year (median [IQR], $2704 [$954-$13 909] vs $5375 [$1283-$22 466]) postdiagnosis costs were lower among Mongolian than among Han children. A higher proportion of Mongolian patients attended low-level hospitals (45.9% vs 17.4%).

CONCLUSIONS AND RELEVANCE

In this cohort study, Mongolian children had a higher incidence and prevalence of cancer but a lower demand for medical care, suggesting that further investigations are needed to identify mechanisms underlying ethnic disparities and ensure that care is equitable.

Association of IKZF1 and CDKN2A gene polymorphisms with childhood acute lymphoblastic leukemia: a high-resolution melting analysis

Background

Acute lymphoblastic leukemia is the most prevailing pediatric hematologic malignancy, and various factors such as environmental exposures and genetic variation affect ALL susceptibility and patients outcome. According to genome-wide association studies, several single nucleotide polymorphisms (SNPs) in IKZF1 (rs4132601) and CDKN2A (rs3731249 and rs3731217) genes are associated with ALL susceptibility. Hereupon, this study aimed to discover the association between these SNPs and the risk of childhood ALL among a sample of the Iranian population.

Methods

A total of fifty children with ALL were included in this case–control study, along with an additional fifty healthy children, matched for age and gender. High-resolution melting (HRM) analysis was employed to genotyping rs4132601, rs3731249, and rs3731217.

Results

In the patient group, the CT genotype and T allele frequency of rs3731249 were significantly greater than controls (p = 0.01 and p = 0.005, respectively). Moreover, the positive association of CT and dominant model (CT + TT) genotypes and T allele at rs3731249 with the risk of ALL was confirmed (OR = 9.56, OR = 10.76 and OR = 11.00, respectively). There was no significant relation between rs4132601 (IKZF1), rs3731217 (CDKN2A), and childhood ALL.

Conclusion

The present study indicates that CT genotype and T allele at rs3731249 (CDKN2A) can significantly increase the risk of ALL among children.

m6A methylation mediates LHPP acetylation as a tumour aerobic glycolysis suppressor to improve the prognosis of gastric cancer

LHPP, a histidine phosphatase, has been implicated in tumour progression. However, its role, underlying mechanisms, and prognostic significance in human gastric cancer (GC) are elusive. Here, we obtained GC tissues and corresponding normal tissues from 48 patients and identified LHPP as a downregulated gene via RNA-seq. qRT-PCR and western blotting were applied to examine LHPP levels in normal and GC tissues. The prognostic value of LHPP was elucidated using tissue microarray and IHC analyses in two independent GC cohorts. The functional roles and mechanistic insights of LHPP in GC growth and metastasis were evaluated in vitro and in vivo. The results showed that LHPP expression was significantly decreased in GC tissues at both the mRNA and protein levels. Multivariate Cox regression analysis revealed that LHPP was an independent prognostic factor and effective predictor in patients with GC. The low expression of LHPP was significantly related to the poor prognosis and chemotherapy sensitivity of gastric cancer patients. Moreover, elevated LHPP expression effectively suppressed GC growth and metastasis in vitro and in vivo. Mechanistically, the m6A modification of LHPP mRNA by METTL14 represses its expression; LHPP inhibits the phosphorylation of GSK3b through acetylation and mediates HIF1A to inhibit glycolysis, proliferation, invasion and metastasis of gastric cancer cells. Together, our findings suggest that LHPP is regulated by m6A methylation and regulates the metabolism of GC by changing the acetylation level. Thus, LHPP is a potential predictive biomarker and therapeutic target for GC.

microRNA-155-5p initiates childhood acute lymphoblastic leukemia by regulating the IRF4/CDK6/CBL axis

Acute lymphoblastic leukemia (ALL) is a common malignancy in children. In this study, we aimed to explore putative mechanisms of microRNA-155-5p (miR-155-5p) involvement in childhood ALL (cALL) via interactions with casitas B-lineage lymphoma (CBL), interferon regulatory factor 4 (IRF4), and cyclin-dependent kinase 6 (CDK6). Bioinformatic analysis was performed initially to identify differentially expressed genes in cALL. The expression levels of miR-155-5p, CBL, IRF4, and CDK6 in peripheral blood lymphocytes from clinical ALL samples were determined using RT-qPCR and Western blot assays. A dual-luciferase reporter gene assay was used to ascertain a possible targeting relationship between miR-155-5p and CBL, CCK-8 assay and flow cytometry were used to measure cell activity and apoptosis of ALL cells. Co-IP was performed to investigate the interaction between CBL and IRF4 and the ubiquitination level of IRF4. Furthermore, in vivo validation was performed inducing xenograft tumor models with ALL cells in nude mice. As indicated by bioinformatic analysis, miR-155-5p and CDK6 were upregulated and CBL was downregulated in ALL. miR-155-5p was found to target CBL to inhibit CBL expression. miR-155-5p promoted the proliferation of ALL cells and inhibited their apoptosis by inhibiting the expression of CBL, which otherwise degraded IRF4 protein through ubiquitination, leading to inhibited CDK6 expression. Collectively, the results show that miR-155-5p can promote the development of cALL via the regulation on CBL-mediated IRF4/CDK6 axis.

As a Novel Tumor Suppressor, LHPP Promotes Apoptosis by Inhibiting the PI3K/AKT Signaling Pathway in Oral Squamous Cell Carcinoma

Oral squamous cell carcinoma (OSCC) refers to the malignant tumor of the head and neck with a highest morbidity. It exhibits a poor prognosis and unsatisfactory treatment partially attributed to delayed diagnosis. As indicated from existing reports, the protein histidine phosphatase LHPP acts as a vital factor in tumorigenesis in liver, lung, bladder, breast and pancreatic tumor tissues. Thus far, the functional mechanism of LHPP in OSCC remains unclear. DGE analysis, OSCC cell lines and OSCC cases were found that LHPP was down-regulated in OSCC tissues and cells compared with that in normal oral mucosa tissues and cells, and was closely related to OSCC differentiation. Cell counting Kit 8 test, EdU proliferation test, scratches test, invasion test, monoclonal formation test, mouse xenograft tumor model, HE staining and immunohistochemistry showed that LHPP inhibited OSCC growth, proliferation and migration in vivo and in vitro. GO and KEGG enrichment analysis, LHPP transcription factor analysis and flow cytometry found that LHPP promotes the apoptosis of OSCC by decreasing the transcriptional activity of p-PI3K and p-Akt. Finally, our results suggested that LHPP inhibited the progression of OSCC through the PI3K/AKT signaling pathway, indicating that LHPP may be a new target for the treatment of OSCC.

Implications of ACMG guidelines to identify high-risk acute lymphoblastic leukemia patients with hereditary cancer susceptibility syndromes (HCSS) in a highly consanguineous population

BACKGROUND

Hereditary cancer susceptibility syndrome (HCSS) contributes to the cancer predisposition at an early age, therefore, identification of HCSS has found to be crucial for surveillance, managing therapeutic interventions and refer the patients and their families for genetic counselling. The study aimed to identify ALL patients who meet the American College of Medical Genetics (ACMG) criteria and refer them for the genetic testing for HCSS as hereditary leukemia and hematologic malignancy syndrome, and to elucidate the significance of high consanguinity with the prevalence of inherited leukemia in Pakistani population.

METHODS

A total of 300 acute lymphoblastic leukemia patients were recruited from the Children's Hospital, Lahore, Pakistan from December 2018 to September 2019. A structured self-reporting questionnaire based on family and medical history of the disease was utilized for the data collection.

RESULTS

In our cohort, 60.40% of ALL patients were identified to meet ACMG criteria. Among them, a large number of patients (40.65%) solely fulfil the criteria due to the presence of parental consanguinity. However, parental consanguinity showed protective impact on the onset at early age of disease [OD = 0.44 (0.25-0.77), p-value = 0.00] while, a family history of cancer increased the risk of cardiotoxicity [OD = 2.46 (1.15-5.24), p-value = 0.02]. Parental consanguinity shows no significant impact on the family history of cancer and the number of relatives with cancer.

CONCLUSIONS

More than 50% of the ALL patients were considered the strong candidates' for genetic testing of HCSS in the Pakistani population, and parental consanguinity was the leading criteria fulfilled by the individuals when assessed through ACMG guidelines. Our study suggests revisiting ACMG guidelines, especially for the criterion of parental consanguinity, and formulating the score based criteria based on; genetic research, the toxicology profile, physical features, personal and family history of cancer for the identification of patients for the genetic testing.

ARID5B rs10821936 and rs10994982 gene polymorphism and susceptibility to juvenile systemic lupus erythematosus and lupus nephritis

BACKGROUND

The prevalence of SLE and the spectrum of clinical manifestations vary widely in different races and geographical populations.

OBJECTIVE

To investigate the possible role of ARID5B rs10821936 and rs10994982 polymorphism as a risk factor for the development of SLE in children (jSLE) and to evaluate their role in relation to clinical manifestations especially lupus nephritis (LN).

METHODS

DNA extraction and Real-time PCR genotyping of ARID5B rs10821936 and rs10994982 were done for 104 jSLE and 282 healthy controls.

RESULTS

The C allele and C containing genotypes (CC, CT and CC+CT) of ARID5B rs10821936 were higher in children with SLE (p = 0.009, OR = 1.56, 0.037, OR = 2.35, 0.016, OR = 1.81 and 0.008 OR = 1.88 respectively). ARID5B rs10994982 alleles, genotypes and haplotypes are not associated with jSLE (p > 0.05). The ARID5B rs10821936 and rs10994982 genotypes showed non-significant associations with LN, proliferative versus non proliferative and biopsy grades (p > 0.05).

CONCLUSION

ARID5B rs10821936 SNP may be a susceptibility risk factor for juvenile SLE in the studied cohort of Egyptian children.

LHPP-Mediated Histidine Dephosphorylation Suppresses the Self-Renewal of Mouse Embryonic Stem Cells

Self-renewal of embryonic stem cells (ESCs) is orchestrated by a vast number of genes at the transcriptional and translational levels. However, the molecular mechanisms of post-translational regulatory factors in ESC self-renewal remain unclear. Histidine phosphorylation, also known as hidden phosphorylation, cannot be detected by conventional experimental methods. A recent study defined phospholysine phosphohistidine inorganic pyrophosphate phosphatase (LHPP) as a histidine phosphatase, which regulates various biological behaviors in cells via histidine dephosphorylation. In this study, the doxycycline (DOX)-induced hLHPP-overexpressing mouse ESCs and mouse LHPP silenced mESCs were constructed. Quantitative polymerase chain reaction (qPCR), western blotting analysis, immunofluorescence, Flow cytometry, colony formation assays, alkaline phosphatase (AP) and bromodeoxyuridine (Brdu) staining were performed. We found that the histidine phosphorylation level was strikingly reduced following LHPP overexpression. Besides, the expression of Oct4 and Lefty1, indispensable genes in the process of ESCs self-renewal, was significantly down-regulated, while markers related to the differentiation were markedly elevated. Moreover, LHPP-mediated histidine dephosphorylation induced G_0/G₁ phase arrest in mESCs, suggesting LHPP was implicated in cell proliferation and cell cycle. Conversely, silencing of Lhpp promoted the self-renewal of mESCs and reversed the RA induced increased expression of genes associated with differentiation. Mechanistically, our findings suggested that the enzymatic active site of LHPP was the cysteine residue at position 226, not 53. LHPP-mediated histidine dephosphorylation lowered the expression levels of β-catenin and the cell cycle-related genes CDK4 and CyclinD1, while it up-regulated the cell cycle suppressor genes P21 and P27. Taken together, our findings reveal that LHPP-mediated histidine dephosphorylation plays a role in the self-renewal of ESCs. LHPP-mediated histidine dephosphorylation inhibited the self-renewal of ESCs by negatively regulating the Wnt/β-catenin pathway and downstream cell cycle-related genes, providing a new perspective and regulatory target for ESCs self-renewal.

Novel germline TRAF3IP3 mutation in a dyad with familial acute B lymphoblastic leukemia

Background

Acute lymphoblastic leukemia (ALL) is the most common hematologic malignancy in children, representing 25% of all new cancer diagnoses. Advances in genomic sequencing have demonstrated that inherited genetic risk factors play a larger role in leukemia development than previously appreciated.

Aim

We identified a father–daughter dyad with childhood B‐cell ALL and aimed to investigate whether the pair shared a gene associated with leukemia predisposition.

Methods

We performed whole exome sequencing on their leukemia and germline samples and RNA‐seq on their leukemia samples.

Results

We discovered a novel germline chromosomal structural variant in chromosome 1q32.2 within the TRAF3IP3 gene. TRAF3IP3 regulates B‐cell lymphopoiesis, and this mutation likely resulted in a predisposition to leukemia by causing expansion of immature B‐cell precursors which are highly vulnerable to secondary somatic mutations. Based on the lack of concordance in the somatic mutational profiles between this dyad's leukemia samples, we suspect that the acquired somatic mutations rather than this germline mutation are what dictated their leukemia phenotypes, which we confirmed through RNA‐seq by comparing to sporadic cases of B‐cell ALL.

Conclusion

This research may have identified a novel gene involved in leukemogenesis which may also be involved in de novo cases of ALL. Additional studies are needed to further characterize this TRAF3IP3 structural variant, the co‐occurring somatic mutations within these leukemia samples and their combined role in leukemogenesis.

LHPP exerts a tumor-inhibiting role in glioblastoma via the downregulation of Akt and Wnt/β-catenin signaling

Phospholysine phosphohistidine inorganic pyrophosphate phosphatase (LHPP) has been recently identified as a novel inhibitor of multiple tumors; however, its role in glioblastoma (GBM) has not been investigated. This study aimed to evaluate whether LHPP exerts a potential tumor-inhibiting role in GBM. Compared with that in normal tissues, LHPP expression was lower in GBM tissues and various GBM cell lines. LHPP up-regulation in GBM cells markedly reduced their proliferation and invasion, and its knockdown had an oncogenic effect on these cells. Further studies revealed that overexpressed LHPP decreased the levels of Akt and glycogen synthase-3β phosphorylation and down-regulated Wnt/β-catenin signaling. By contrast, LHPP knockdown produced opposite effects. Akt suppression markedly abrogated the activation of Wnt/β-catenin signaling induced by LHPP knockdown. The reactivation of Wnt/β-catenin signaling partially reversed the inhibition of tumor growth in GBM mediated by LHPP overexpression. In addition, LHPP overexpression markedly retarded the tumorigenesis of GBM cells in vivo. These findings revealed that LHPP acts a potential inhibitor of tumor growth in GBM, and its overexpression represses GBM proliferation and invasion by down-regulating Akt and Wnt/β-catenin signaling. This work highlights the crucial role of LHPP in GBM progression and suggests its potential as an anticancer target for the treatment of this disease.

Indoor volatile organic compounds exposures and risk of childhood acute leukemia: a case-control study in shanghai

A case-control study was conducted to investigate the relationship between indoor air pollution and childhood acute leukemia (AL) in Shanghai. 97 cases and 148 gender-, age-, and residence-matched controls were included. Indoor air pollution was evaluated by questionnaires and quantitative measurement including 14 volatile organic compounds (VOCs) and nitrogen dioxide (NO₂) in the homes of the two groups. The levels of individual VOCs, VOC families, TVOC (sum of the concentrations of the individual VOCs) and NO₂ were compared between the two groups. Exposure to styrene and butyl alcohol were associated with an increased risk of childhood AL (styrene: odds ratio (OR)=2.33, 95% confidence interval (CI): 1.07-5.07; butyl alcohol: OR = 2.51, 95%CI: 1.19-5.28); 4th quartile of chlorinated hydrocarbons (OR = 2.52, 95%CI: 1.02-6.26) and 3rd quartile of TVOC (OR = 4.03, 95%CI: 1.06-6.81) had significant higher ORs for childhood AL compared with that in the lowest quartiles. Elevated levels of individual VOCs, VOC families and TVOC were also associated with self-reported risk factors. Our findings suggest that VOCs exposure was associated with an elevated risk of childhood AL, underscore that more attention should be paid to indoor air pollution as a risk factor of childhood AL.

Role of rs10406069 in miR-5196 in hyperdiploid childhood acute lymphoblastic leukemia

Aim: To determine the role of single nucleotide polymorphisms (SNPs) in noncoding RNAs in childhood acute lymphoblastic leukemia (ALL) subtypes. Materials & methods: We screened all SNPs in 130 pre-miRNA genes to assess their role in the susceptibility of the most common subtypes of ALL: hyperdiploid and ETV6-RUNX1. Results: In two independent cohorts, we found a significant association between rs10406069 in miR-5196 and the risk of developing hyperdiploid ALL. This observation could be explained by the impact of the SNP on miR-5196 expression and in turn, in its target genes. Indeed, rs10406069 was associated with expression changes in SMC1A, a gene involved in sister chromatin cohesion. Conclusion: rs10406069 in miR-5196 may have a relevant role in hyperdiploid ALL risk.

The expression and clinical significance of murine double minute 2, lysosome-associated membrane protein 1, and P-glycoprotein in pediatric acute lymphoblastic leukemia

BACKGROUND

To analyze the expression and clinical significance of murine double minute 2 (MDM2), lysosome-associated membrane protein (LAMP1) and P-glycoprotein (P-gp) in children with acute lymphoblastic leukemia (ALL).

METHODS

Thirty-three children with ALL who were admitted to our hospital between January 2017 and January 2018 were enrolled as the ALL group. The expression of MDM2, LAMP1 and P-gp was compared between the two groups, as well as between ALL patients with different clinical characteristics. Logistic regression was used to analyze the risk factors that affect the prognosis and survival of ALL patients. Kaplan-Meier survival curves were used to analyze the correlations of MDM2, LAMP1 and P-gp on the prognosis and survival of ALL patients.

RESULTS

The expression levels of MDM2, LAMP1 and P-gp in the ALL group were higher than those in the control group (P<0.05). The average survival time of the group with low expression of MDM2 was (34.92±0.56) months, the average survival time of the group with high expression of MDM2 was (31.32±0.42) months, and the difference was statistically significant (P<0.05). The average survival time of the group with low expression of LAMP1 was (36.71±0.55) months, the average survival time of the group with high expression of LAMP1 was (29.87±0.40) months, the difference was statistically significant (P<0.05). The average survival time of the group with low expression of P-gp was (36.29±0.41) months, the average survival time of the group with high expression of P-gp was (26.46±0.37) months, and the difference was statistically significant (P<0.05).

CONCLUSIONS

Abnormal expression levels of MDM2, LAMP1 and P-gp protein are related to the occurrence and development of ALL, and are closely related to patient prognosis and survival. Therefore, MDM2, LAMP1and P-gp can serve as molecular markers for predicting the prognosis of children with ALL.

Evaluation of Cytotoxic Potentials of Novel Cyclooxygenase-2 Inhibitor against ALL Lymphocytes and Normal Lymphocytes and Its Anticancer Effect through Mitochondrial Pathway

In the present study, we searched selective cytotoxicity and mitochondria mediated apoptosis of novel COX-2 inhibitor 2-(4-(Methylsulfonyl)phenyl)imidazo[1,2-a] pyridine-8-carboxylic acid on B-lymphocytes and their mitochondria isolated from normal subjects and acute lymphoblastic leukemia (ALL) patients' blood. Our results showed this compound can selectively induce cellular and mitochondrial toxicity on ALL B-lymphocytes and mitochondria without any toxic effects on normal B-lymphocytes and their mitochondria. Taken together, the results of this study suggest that cancerous mitochondria are a potential target for the ALL B-lymphocytes. Selective toxicity of COX-2 inhibitor in cancerous mitochondria could be an attractive therapeutic option for the effective clinical management of therapy-resistant ALL.

The Significance of Circular RNA DDX17 in Prostate Cancer

Circular RNA DDX17 (circDDX17) has been demonstrated as a tumor suppressor in colorectal cancer. However, mechanisms underlying circDDX17 effects in cases of prostate cancer (PCa) are not well understood. Thus, herein, we determined measures of circDDX17 expression by use of the TCGA database. Expression of circDDX17 in prostate cancer-afflicted tissue samples was determined by qRT-PCR. Functionally, circDDX17 induced remarkable inhibition of cell colonizing ability, invasion, and epithelial-mesenchymal transition (EMT) progression in vitro. Mechanistically, dual-luciferase reporter assays, RNA immunoprecipitation, and RNA pull-down experiments helped verify interactions between circDDX17 and miR-346. Low expression of circDDX17 occurred in TCGA PCa samples. Furthermore, circDDX17 expression was downregulated significantly in PCa. These results suggested that circDDX17 suppressed PC cell mobility, proliferation, and invasion. Mechanistic experiments indicated that circDDX17 might serve as a ceRNA of miR-346 to relieve repressive effects of miR-346 upon phospholysine phosphohistidine inorganic pyrophosphate phosphatase (LHPP). LHPP expression itself was downregulated in TCGA PCa samples. Overall, our findings indicated that the circDDX17/miR-346/LHPP pathway inhibited the progression of prostate cancer and that circDDX17 may be a new potential therapeutic or diagnostic target for treating and diagnosing prostate cancer. As our study also demonstrated for the first time that LHPP might act as an anticancer gene in prostate cancer, the findings could have wide-ranging implications for the treatment of this affliction.

miRNA deregulation in childhood acute lymphoblastic leukemia: a systematic review

Despite remarkable improvements in survival of childhood acute lymphoblastic leukemia (ALL), nonresponding or relapsing patients still represent one of the most frequent causes of death by disease in children. Accurate patient risk stratification based on genetic markers could increases survival rates. miRNAs can represent novel candidates with diagnostic, predictive and prognostic potential; however, many groups investigated their involvement with contradictory results. Aim: To clarify the role of miRNAs as biomarkers through a systematic review. Results: From a revision of 45 manuscripts, we found that miR-128 and miR-181 overexpression could represent markers for ALL diagnosis and underexpression of miR-708 and miR-99a could be markers for bad prognosis. Conclusion: These signatures could refine classification and risk stratification of patients and improve ALL outcome.

ARID5B rs10821936 and rs10994982 gene polymorphisms and acute lymphoblastic leukemia: relation to disease susceptibility and outcome

ARID5B rs10821936 and rs10994982 single nucleotide polymorphism (SNP) have been associated with the risk of acute lymphoblastic leukemia (ALL) in different ethnic populations. We investigated the association between the ARID5B rs10821936 C > T, rs10994982 A > G, and susceptibility to ALL in a cohort of Egyptian individuals and investigated their role in relation to disease outcome. Real-time PCR typing was done for ARID5B rs10821936 and rs10994982 SNPs for 128 pediatric ALL (pALL), 45 adult ALL (aALL), and 436 healthy controls. Significant risk associations were found between the C allele (p < 0.001, OR = 2.02), CC genotype (p < 0.001, OR = 2.72), CT genotype (p = 0.011, OR = 1.45) of ARID5B rs10821936 and pediatric ALL especially T-ALL and adult ALL (p < 0.05). The CA haplotype (C allele of rs10821936 + A allele of rs10994982) was associated with the risk of ALL either pediatric ALL or adult ALL (p < 0.001). In the studied Egyptian population, it can be concluded that the C allele, CC, and CT genotypes of ARID5B rs10821936 and the CA haplotype may be a susceptibility risk factor for pediatric and adult ALL. However, the SNPs of ARID5B rs10821936 and rs10994982 were not found to be strongly associated with ALL outcomes.

Genetic diversity, inbreeding and cancer

Genetic diversity is essential for adaptive capacities, providing organisms with the potential of successfully responding to intrinsic and extrinsic challenges. Although a clear reciprocal link between genetic diversity and resistance to parasites and pathogens has been established across taxa, the impact of loss of genetic diversity by inbreeding on the emergence and progression of non-communicable diseases, such as cancer, has been overlooked. Here we provide an overview of such associations and show that low genetic diversity and inbreeding associate with an increased risk of cancer in both humans and animals. Cancer being a multifaceted disease, loss of genetic diversity can directly (via accumulation of oncogenic homozygous mutations) and indirectly (via increased susceptibility to oncogenic pathogens) impact abnormal cell emergence and escape of immune surveillance. The observed link between reduced genetic diversity and cancer in wildlife may further imperil the long-term survival of numerous endangered species, highlighting the need to consider the impact of cancer in conservation biology. Finally, the somewhat incongruent data originating from human studies suggest that the association between genetic diversity and cancer development is multifactorial and may be tumour specific. Further studies are therefore crucial in order to elucidate the underpinnings of the interactions between genetic diversity, inbreeding and cancer.

A genetic variant in miR-100 is a protective factor of childhood acute lymphoblastic leukemia

BACKGROUND

In the past decade, miR-100, miR-146a, and miR-210 were reported to be dysregulated in childhood acute lymphoblastic leukemia (ALL). However, effects of genetic variants in these three microRNAs have not been investigated in Chinese population.

METHODS

In this study, we conducted a case-control study to evaluate the relationship between genetic variants in miR-100, miR-146a, and miR-210 and the risk of childhood ALL in Chinese population. Subsequently, plasma expression level of miR-100 was also detected.

RESULT

We found that subjects carrying mutant homozygous TT genotype of miR-100 rs543412 had a statistically significantly decreased risk of childhood ALL (adjusted odds ratio [OR] = 0.73, 95% confidence interval [CI] = 0.55-0.97, P = 0.029). This protective effect was also observed among subjects whose parents were ever drinkers (adjusted OR = 0.53, 95% CI = 0.29-0.94), or whose living house were ever painted (adjusted OR = 0.57, 95% CI = 0.34-0.94). Besides, rs543412 variant homozygous TT had a significantly protective role in patients with childhood B-ALL. Finally, we found that expression level of miR-100 in plasma of childhood ALL cases was significantly higher than that of noncancer controls.

CONCLUSION

Our study suggested that there was significant association between the polymorphisms in miR-100 (rs543412) and decreased susceptibility to childhood ALL.

IFNG +874 A/T is associated with acute lymphoblastic leukemia in Mexican Mestizos

Acute lymphoblastic leukemia (ALL), the most common type of cancer in children worldwide, has one of the highest incidence rates in Mexico. It is a multifactorial disease and different cytokine single nucleotide polymorphisms (SNP), have been associated with ALL expression. Few studies have been published analyzing IFNG +874 T/A and IL2 -330 G/T in this type of leukemia. These SNPs are involved in high or low expression, and are central to cellular immunity, influencing greatly tumor growth. The purpose of this work was to explore the association of IFNG +874 A/T (rs2430561) and IL2 -330 G/T (rs2069762) SNPs with ALL susceptibility and/or protection in 488 Mexican Mestizos patients, as compared to 950 Mexican Mestizo healthy controls. The results demonstrated that IFNG +874 T allele (pc = 0.00004, OR = 0.673) and the TT genotype (pc = 0.00015, OR = 0.349), protect against ALL expression with no specific gender association; however, the TT homozygote genotype (vs. TA+AA) seems more protective in males (pc = 0.00683). IL2 -330 G/T does not contribute to the development of ALL. In healthy Mexicans, the most common genotypes for IL2 and IFNG, are the low cytokine producers, suggesting that the genetic background in this ethnic group, may be partly responsible for the high incidence of ALL. These results show for the first time in Mexicans, the relevant role that IFNG SNP has in the genetic etiology of ALL. Thus, a large group of patients belonging to different ethnicities will be very helpful to study in order to demonstrate if these SNPs contribute to the genetic etiology of ALL, as shown here in Mexican Mestizos.

In utero gene expression in the Slc39a8(neo/neo) knockdown mouse

Slc39a8 encodes ZIP8, a divalent cation/bicarbonate symporter expressed in pluripotent mouse embryonic stem cells, and therefore ubiquitous in adult tissues; ZIP8 influxes Zn²⁺, Mn²⁺ and Fe²⁺. Slc39a8(neo/neo) knockdown mice exhibit 10-15% of wild-type ZIP8 mRNA and protein levels, and show pleiotropic phenotype of stunted growth, neonatal lethality, multi-organ dysmorphogenesis, and dysregulated hematopoiesis manifested as severe anemia. Herein we performed RNA-seq analysis of gestational day (GD)13.5 yolk sac and placenta, and GD16.5 liver, kidney, lung, heart and cerebellum, comparing Slc39a8(neo/neo) with Slc39a8(+/+) wild-type. Meta-data analysis of differentially-expressed genes revealed 29 unique genes from all tissues - having enriched GO categories associated with hematopoiesis and hypoxia and KEGG categories of complement, response to infection, and coagulation cascade - consistent with dysregulated hematopoietic stem cell fate. Based on transcription factor (TF) profiles in the JASPAR database, and searching for TF-binding sites enriched by Pscan, we identified numerous genes encoding zinc-finger and other TFs associated with hematopoietic stem cell functions. We conclude that, in this mouse model, deficient ZIP8-mediated divalent cation transport affects zinc-finger (e.g. GATA proteins) and other TFs interacting with GATA proteins (e.g. TAL1), predominantly in yolk sac. These data strongly support the phenotype of dysmorphogenesis and anemia seen in Slc39a8(neo/neo) mice in utero.

Involvement of SNPs in miR-3117 and miR-3689d2 in childhood acute lymphoblastic leukemia risk

Acute lymphoblastic leukemia (ALL) is the most common cancer in children. Numerous studies have shown that microRNAs (miRNAs) could play a role in this disease. Nowadays, more than 2500 miRNAs have been described, that regulate more than 50% of genes, including those involved in B-cell maturation, differentiation and proliferation. Genetic variants in miRNAs can alter their own levels or function, affecting their target gene expression, and then, may affect ALL risk. Therefore, the aim of this study was to determine the role of miRNA genetic variants in B-ALL susceptibility. We analyzed all variants in pre-miRNAs (MAF > 1%) in two independent cohorts from Spain and Slovenia and inferred their functional effect by in silico analysis. SNPs rs12402181 in miR-3117 and rs62571442 in miR-3689d2 were associated with ALL risk in both cohorts, possibly through their effect on MAPK signalling pathway. These SNPs could be novel markers for ALL susceptibility.