The Differences of Serum Thrombopoietin Levels Between Acquired Aplastic Anemia and Immune Thrombocytopenia in Pediatric Patients.

Thrombopoietin (TPO) is the critical regulator of platelet production. However, the role of TPO in pediatric patients with thrombocytopenic disorders has not been fully elucidated. In the present study, we attempted to investigate serum TPO levels in patients with acquired aplastic anemia (aAA) and immune thrombocytopenia (ITP). We analyzed the endogenous plasma concentration of TPO and platelet count at the time of TPO measurement in 166 patients with aAA and 280 patients with ITP retrospectively. We further observed a correlation between platelet counts and TPO. Serum TPO levels were significantly higher in aAA compared with ITP (1142 vs. 77.99 pg/mL, P<0.001). In patients with aAA, an elevation for TPO levels in very severe AA (VSAA) was seen when compared with non-severe AA (NSAA) (1360 vs. 984.4 pg/mL, P<0.05). In contrast, the circulating TPO levels with chronic ITP (CITP) showed a decrease than newly diagnosed ITP (NITP) and persistent ITP (PITP) (62.28 vs. 81.56 pg/mL, P<0.01, 62.28 vs. 87.82 pg/mL, P<0.05, respectively). There was a negative correlation between platelet counts and TPO levels in aAA (rs=-0.3325, P<0.001) as well as ITP (rs=-0.2570, P<0.001). Especially, TPO levels were inversely correlated with platelet counts in NSAA (rs=-0.3672, P<0.001) and NITP (rs=-0.3316, P<0.001). After grouping by age or sex, there were no statistical differences in aAA or ITP. Serum TPO levels were markedly elevated in pediatric patients with aAA compared with ITP. It was higher in VSAA and lower in CITP, suggesting that serum TPO level could play a role in classifying disease severity or clinical course in aAA and ITP.

HIF-1α induced by hypoxic condition regulates Treg/Th17 axis polarization in chronic immune thrombocytopenia.

Immune thrombocytopenia (ITP) is an acquired immune disorder characterized by increased platelet destruction and reduced platelet (Plt) production. Hypoxia-inducible factor-1α (HIF-1α) have regulatory effects on Treg/Th17 axis balance and may represent relevant factors in the pathogenesis of ITP. Treg/Th17 ratio, serum levels and gene expression were investigated in new diagnosed ITP (NITP) and chronic ITP (CITP). The Treg/Th17 ratio obviously decreased in CITP (P = 0.001). The ratio of Treg/Th17 was correlated with the level of HIF-1α level both in mRNA (r = 0.49, P < 0.0001) and serum level (r = 0.50, P < 0.0001). However, none statistical upregulation of HIF-1α was observed in CITP. In vitro, There was significant polarization difference of Treg/Th17 axis (P = 0.042) and Foxp3-MFI/IL17-MFI (P = 0.0003) in hypoxic condition between NITP and CITP. These findings suggest that HIF-1α induced by hypoxia plays a crucial role in the chronicity of ITP by mediating the imbalance of the Treg/Th17 axis.

Efficacy and safety of avatrombopag in Chinese children with persistent and chronic primary immune thrombocytopenia: A multicentre observational retrospective study in China.

Avatrombopag (AVA) is a novel thrombopoietin receptor agonist (TPO-RA) that has been recently approved as a second-line therapy for immune thrombocytopenia (ITP) in adults; however, its safety and efficacy data in children are lacking. Here, we demonstrated the efficacy and safety of AVA as second-line therapy in children with ITP. A multicentre, retrospective, observational study was conducted in children with persistent or chronic ITP who did not respond to or relapsed from previous treatment and were treated with AVA for at least 12 weeks between August 2020 and December 2022. The outcomes were the responses (defined as achieving a platelet count ≥30 × 109/L, twofold increase in platelet count from baseline and absence of bleeding), including rapid response within 4 weeks, sustained response at weeks 12 and 24, bleeding control and adverse events (AEs). Thirty-four (18 males) patients with a mean age of 6.3 (range: 1.9-15.3) years were enrolled. The median number of previous treatment types was four (range: 1-6), and 41.2% patients switched from other TPO-RAs. Within 4 weeks, overall response (OR) was achieved in 79.4% patients and complete response (CR, defined as a platelet count ≥100 × 109/L and the absence of bleeding) in 67.7% patients with a median response time of 7 (range: 1-27) days. At 12 weeks, OR was achieved in 88.2%, CR in 76.5% and sustained response in 44% of patients. At 24 weeks, 22/34 (64.7%) patients who achieved a response and were followed up for 24 weeks were evaluated; 12/22 (54.55%) achieved a sustained response. During AVA therapy, median platelet counts increased by week 1 and were maintained throughout the treatment period. The proportion of patients with grade 1-3 bleeding decreased from 52.95% at baseline to 2.94% at 12 weeks, while concomitant ITP medications decreased from 36.47% at baseline to 8.82% at 12 weeks, with only 9 (26.47%) patients receiving rescue therapy 23 times within 12 weeks. There were 61.8% patients with 59 AEs: 29.8% with Common Terminology Criteria for Adverse Events grade 1 and the rest with grade 2. These findings show that AVA could achieve a rapid and sustained response in children with persistent or chronic ITP as a second-line treatment, with good clinical bleeding control and reduction of concomitant ITP therapy, without significant AEs.

An integrated analysis of DNA promoter methylation, microRNA regulation, and gene expression in gastric adenocarcinoma.

BACKGROUND: Gastric adenocarcinoma (GAC), a common type of gastric cancer, poses a significant public health threat worldwide. This study aimed to determine the transcriptional regulatory mechanisms of GAC. METHODS: HTSeq-FPKM raw data were obtained from The Cancer Genome Atlas Stomach Adenocarcinoma data collection. Subsequently, the limma package in R was used to identify differentially expressed genes (DEGs). Differentially methylated genes (DMGs), DEGs, and differentially expressed microRNAs (miRNAs) in normal, and tumor tissues of the same patients were screened and compared using R software tools. A functional enrichment analysis was performed using Gene Ontology (GO) and the Kyoto Encyclopedia of Genes and Genomes (KEGG) for various DEGs, DMGs, promoter methylation, and miRNAs. DEG-specific methylation and transcription factors were analyzed using ENCODE ChIP-seq. RESULTS: DEGs were centrally modified by the histone trimethylation of lysine 27 on histone H3 (H3K27me3). Upstream transcription factors of DEGs were enriched in different ChIP-seq clusters, such as Forkhead Box M1, E2F Transcription Factor 4, and suppressor of zest 12. Integrated regulatory networks of DEGs, promoter methylation, and miRNAs were constructed. Two miRNAs (hsa-mir-1 and hsa-mir-133a) and four DEGs (A disintegrin and metalloproteinase domain 12, transcription factor AP-2 alpha, solute carrier family 5 member 7, and cadherin 19) separately played important roles in the integrated regulatory network. Therefore, these DEGs, DMGs, promoter methylation, and miRNAs may play an important role in GAC pathogenesis. CONCLUSIONS: In summary, the present study results provide insights into the oncogenesis and progression of GAC, thus accelerating the development of novel targeted GAC therapies.