The Extensive Regulation of MicroRNA in Immune Thrombocytopenia

miR-28-5p targeted Rap1b attenuates splenic inflammation infiltration in immune thrombocytopenia

Immune thrombocytopenia (ITP) is an autoimmune disease with isolated platelet count decrease. A subset of patients responds inferiorly to the first-line therapies including glucocorticoid and intravenous immunoglobulins (IVIG), of which the underlying mechanisms have not been fully elucidated. We first found that expression of miR-28-5p was obviously increased in complete responders, and decreased to substantially low levels in partial or non-responders. In the passive ITP model, upregulation of miR-28-5p by injecting agomir slightly improved thrombocytopenia, and obviously inhibited the Rap1b gene expression. Luciferase reporter assay demonstrated there was significant decrease of luciferase activity in 293T cells co-transfected with miR-28-5p mimics and plasmids with Rap1b wide-type sequence. Upregulation of miR-28-5p, and downregulation of Rap1b played a favorable role in reducing B cell infiltration in the marginal zone of spleen in mice. However, miR-28-5p exhibited no significant influence on megakaryocyte maturation in ITP both in vitro and in vivo studies. Finally, we confirmed that miR-28-5p upregulation was associated with superior early treatment response in ITP, and possibly functioned by targeting Rap1b gene to inhibit humoral immunity.

The ITP diagnostic challenge

Despite numerous advances, the diagnosis of immune thrombocytopenia (ITP) remains a diagnosis of exclusion. This commentary analyses and contextualizes the recent report from Garabet et al. that MicroRNA-199a-5p could be used as a diagnostic marker for ITP. Commentary on: Garabet et al. MicroRNA-199a-5p may be a diagnostic biomarker of primary ITP. Br J Haematol 2025 (Online ahead of print). doi: 10.1111/bjh.19987.

The role of eosinophil counts and megakaryocyte nuclei for distinction of acute and chronic immune thrombocytopenic purpura

OBJECTIVE

Immune thrombocytopenic purpura (ITP), the most common cause of thrombocytopenia, is clinically classified as acute and chronic. This study aimed to distinguish between acute/chronic ITP parameters examined at diagnosis via complete blood count (CBC), peripheral blood (PB) and bone marrow aspirate (BMA) smears. It would also contribute to early treatment options, cost-effective policies, and the life quality of patients.

METHODS

This study consisted of 304 ITP patients aged under 18 years diagnosed and followed up between 1982-2018. Differences between acute and chronic groups were compared by eosinophilia, megakaryocytes (MKs), and megakaryocyte nuclei. Diagnostic scales were created using simple parameters both to guide the distinction between acute and chronic ITP as well as for the prediction of the chronic progression of the patients at diagnosis.

RESULTS

Of the patients in this study, 71% had acute and 29% had chronic ITP. In CBC and PB smears, eosinophil and lymphocyte counts were higher in acute whereas neutrophil counts were higher in chronic ITP patients. Eosinophil counts in the BMA were also significantly higher in acute ITP patients. There was no significant difference in MK counts. However, the mean number of MK nuclei was higher in acute ITP patients.

CONCLUSION

Comparison analyses between acute/chronic ITP with the methods developed for the first time are low-cost and promising. Using only eosinophil percentages in the CBC and PB smear, we could identify acute cases by 100%. Further studies including the integration of our study and clinical risk scoring models would contribute to the diagnosis and treatment process of ITP.

Autoimmune effector mechanisms associated with a defective immunosuppressive axis in immune thrombocytopenia (ITP)

Immune thrombocytopenia (ITP) is an autoimmune disease characterized by an isolated thrombocytopenia and variable phenotype as some patients suffer no bleeding whilst others have bleeding from mild to severe, which may be fatal. This variability probably reflects the disease's complex pathophysiology; a dysregulated hyperreactive immune effector cell response involving the entire adaptive immune system (e.g. B and T cell subsets) that leads to platelet and megakaryocyte (MK) destruction. It appears that these effector responses are due to a breakdown in immune tolerance, and this is characterized by defects in several immunosuppressive cell types. These include defective T regulatory cells (Tregs), B regulatory cells (Bregs) and Myeloid-derived suppressor cells (MDSC), all of which are all intimately associated with antigen presenting cells (APC) such as dendritic cells (DC). The loss of this immunosuppressive axis allows for the activation of unchecked autoreactive T cells and B cells, leading to the development of autoantibodies and cytotoxic T cells (CTL), which can directly destroy platelets in the periphery and inhibit MK platelet production in the bone marrow (BM). This review will focus on the effector cell mechanisms in ITP and highlight the defective immunosuppressive axis that appears responsible for this platelet-specific immune hyperreactivity.

Unraveling the noncoding RNA landscape in glioblastoma: from pathogenesis to precision therapeutics

Glioblastoma (GBM) is an aggressive type IV brain tumor that originates from astrocytes and has a poor prognosis. Despite intensive research, survival rates have not significantly improved. Noncoding RNAs (ncRNAs) are emerging as critical regulators of carcinogenesis, progression, and increased treatment resistance in GBM cells. They influence angiogenesis, migration, epithelial-to-mesenchymal transition, and invasion in GBM cells. ncRNAs, such as long ncRNAs (lncRNAs), microRNAs (miRNAs), and circular RNAs (circRNAs), are commonly dysregulated in GBM. miRNAs, such as miR-21, miR-133a, and miR-27a-3p, are oncogenes that increase cell proliferation, metastasis, and migration by targeting TGFBR1 and BTG2. In contrast, lncRNAs, such as HOXD-AS2 and LINC00511, are oncogenes that increase the migration, invasion, and proliferation of cells. CircRNAs, such as circ0001730, circENTPD7, and circFOXO3, are oncogenes responsible for cell growth, angiogenesis, and viability. Developing novel therapeutic strategies targeting ncRNAs, cell migration, and angiogenesis is a promising approach for GBM. By targeting these dysregulated ncRNAs, we can potentially restore a healthy balance in gene expression and influence disease progression. ncRNAs abound within GBM, demonstrating significant roles in governing the growth and behavior of these tumors. They may also be useful as biomarkers or targets for therapy. The use of morpholino oligonucleotides (MOs) suppressing the oncogene expression of HOTAIR, BCYRN1, and cyrano, antisense oligonucleotides (ASOs) suppressing the expression of ncRNAs such as MALAT1 and miR-10b, locked nucleic acids (LNAs) suppressing miR-21, and peptide nucleic acids (PNAs) suppressing the expression of miR-155 inhibited the PI3K pathway, tumor growth, angiogenesis, proliferation, migration, and invasion. Targeting oncogenic ncRNAs with RNA-interfering strategies such as MOs, ASOs, LNAs, CRISPR-Cas9 gene editing, and PNA approaches may represent a promising therapeutic strategy for GBM. This review emphasizes the critical role of ncRNAs in GBM pathogenesis, as well as the potential for new therapeutic strategies targeting these pathways to improve the prognosis and quality of life for GBM patients.

The Many Faces of Immune Thrombocytopenia: Mechanisms, Therapies, and Clinical Challenges in Oncological Patients

The pathogenesis of immune thrombocytopenia (ITP) is complex and involves the dysregulation of immune cells, such as T and B lymphocytes, and several cytokines that promote the production of autoantibodies. In the context of cancer patients, ITP can occur in both primary and secondary forms related to anticancer therapies or the disease itself.

OBJECTIVE

In light of these data, we decided to prepare a literature review that will explain the classification and immunological determinants of the pathogenesis of ITP and present the clinical implications of this condition, especially in patients with cancer.

MATERIALS AND METHODS

We reviewed the literature on immunological mechanisms, therapies, and challenges in treating ITP, particularly on cancer patients.

RESULTS

The results of the literature review show that ITP in cancer patients can be both primary and secondary, with secondary ITP being more often associated with anticancer therapies such as chemotherapy and immunotherapy. Innovative therapies such as TPO-RA, rituximab, Bruton's kinase inhibitors, and FcRn receptor inhibitors have shown promising results in treating refractory ITP, especially in patients with chronic disease.

CONCLUSIONS

ITP is a significant clinical challenge, especially in the context of oncology patients, where both the disease and treatment can worsen thrombocytopenia and increase the risk of bleeding complications. Treatment of oncology patients with ITP requires an individualized approach, and new therapies offer effective tools for managing this condition. Future research into immunological mechanisms may bring further advances in treating ITP and improve outcomes in cancer patients.

Approaches based on miRNAs in Behçet's Disease: Unveiling pathogenic mechanisms, diagnostic strategies, and therapeutic applications

Behçet's Disease (BD) is an intricate medical puzzle, captivating researchers with its enigmatic pathogenesis. This complex ailment, distinguished by recurrent mouth and genital lesions, eye irritation, and skin injuries, presents a substantial obstacle to therapeutic research. This review explores the complex interaction of microRNAs (miRNAs) with BD, highlighting their crucial involvement in the disease's pathophysiology. miRNAs, recognized for regulatory influence in diverse biological processes, hold a pivotal position in the molecular mechanisms of autoimmune diseases, such as BD. The exploration begins with examining miRNA biogenic pathways and functions, establishing a foundational understanding of their regulatory mechanisms. Shifting to the molecular landscape governing BD, the review highlights miRNA-mediated impacts on critical signaling pathways like Notch, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), and protein kinase B (AKT)/mammalian target of rapamycin (mTOR), offering insights into intricate pathophysiological mechanisms. Dissecting the immunological landscape reveals the profound influence of miRNAs on BD, shedding light on the intricate modulation of immune responses and offering novel perspectives on disease etiology and progression. Beyond molecular intricacies, the review explores the clinical relevance of miRNAs in BD, emphasizing their potential as diagnostic and prognostic indicators. The discussion extends to the promising realm of miRNA-based therapeutic interventions, highlighting their potential in alleviating symptoms and altering disease progression. This comprehensive review, serving as a valuable resource for researchers, clinicians, and stakeholders, aims to decipher the intricate molecular tapestry of BD and explore the therapeutic potential of miRNAs.

Unlocking novel therapeutic avenues in glioblastoma: Harnessing 4-amino cyanine and miRNA synergy for next-gen treatment convergence

Glioblastoma (GBM) poses a formidable challenge in oncology due to its aggressive nature and dismal prognosis, with average survival rates around 15 months despite conventional treatments. This review proposes a novel therapeutic strategy for GBM by integrating microRNA (miRNA) therapy with 4-amino cyanine molecules possessing near-infrared (NIR) properties. miRNA holds promise in regulating gene expression, particularly in GBM, making it an attractive therapeutic target. 4-amino cyanine molecules, especially those with NIR properties, have shown efficacy in targeted tumor cell degradation. The combined approach addresses gene expression regulation and precise tumor cell degradation, offering a breakthrough in GBM treatment. Additionally, the review explores noncoding RNAs classification and characteristics, highlighting their role in GBM pathogenesis. Advanced technologies such as antisense oligonucleotides (ASOs), locked nucleic acids (LNAs), and peptide nucleic acids (PNAs) show potential in targeting noncoding RNAs therapeutically, paving the way for precision medicine in GBM. This synergistic combination presents an innovative approach with the potential to advance cancer therapy in the challenging landscape of GBM.

The miR-641-STIM1 and SATB1 axes play important roles in the regulation of the Th17/Treg balance in ITP

Immune thrombocytopenia (ITP) is an autoimmune disease caused by T-cell dysfunction. Recently, several studies have shown that a disturbed Th17/Treg balance contributes to the development of ITP. MicroRNAs (miRNAs) are small noncoding RNA moleculesthat posttranscriptionally regulate gene expression. Emerging evidences have demonstrated that miRNAs play an important role in regulating the Th17/Treg balance. In the present study, we found that miR-641 was upregulated in ITP patients. In primary T cells, overexpression of miR-641 could cause downregulation of its target genes STIM1 and SATB1, thus inducing a Th17 (upregulated)/Treg (downregulated) imbalance. Inhibition of miR-641 by a miR-641 sponge in primary T cells of ITP patients or by antagomiR-641 in an ITP murine model could cause upregulation of STIM1 and SATB1, thus restoring Th17/Treg homeostasis. These results suggested that the miR-641-STIM/SATB1 axis plays an important role in regulating the Th17/Treg balance in ITP.

The mechanisms of MicroRNA 21 in premature ovarian insufficiency mice with mesenchymal stem cells transplantation : The involved molecular and immunological mechanisms

Umbilical cord-derived mesenchymal stem cell (UCMSC) transplantation has been deeply explored for premature ovarian insufficiency (POI) disease. However, the associated mechanism remains to be researched. To explore whether and how the microRNA 21 (miR-21) functions in POI mice with UCMSCs transplantation, the autoimmune-induced POI mice model was built up, transplanted with or without UCMSCs transfect with the LV-hsa-miR-21-5p/LV-hsa-miR-21-5p-inhibition, with the transfection efficiency analyzed by QRT-PCR. Mice hormone secretion and the anti-Zona pellucida antibody (AZPAb) levels were analyzed, the ovarian morphological changes and folliculogenesis were observed, and the ovarian apoptosis cells were detected to evaluate ovarian function. The expression and localization of the PTEN/Akt/FOXO3a signal pathway-related cytokines were analyzed in mice ovaries.Additionally, the spleen levels of CD8 + CD28-T cells were tested and qualified with its significant secretory factor, interleukin 10 (IL-10). We found that with the LV-hsa-miR-21-5p-inhibition-UCMSCs transplantation, the mice ovarian function can be hardly recovered than mice with LV-NC-UCMSCs transplantation, and the PTEN/Akt/FOXO3a signal pathway was activated. The expression levels of the CD8 + CD28-T cells were decreased, with the decreased levels of the IL-10 expression. In contrast, in mice with the LV-hsa-miR-21-5p-UCMSCs transplantation, the injured ovarian function can be reversed, and the PTEN/AKT/FOXO3a signal pathway was detected activated, with the increased levels of the CD8 + CD28-T cells, and the increased serum levels of IL-10. In conclusion, miR-21 improves the ovarian function recovery of POI mice with UCMSCs transplantation, and the mechanisms may be through suppressing the PTEN/AKT/FOXO3a signal pathway and up-regulating the circulating of the CD8 + CD28-T cells.

MicroRNAs Regulate Function in Atherosclerosis and Clinical Implications

Background

Atherosclerosis is considered the most common cause of morbidity and mortality worldwide. Athermanous plaque formation is pathognomonic of atherosclerosis. The main feature of atherosclerosis is the formation of plaque, which is inseparable from endothelial cells, vascular smooth muscle cells, and macrophages. MicroRNAs, a small highly conserved noncoding ribonucleic acid (RNA) molecule, have multiple biological functions, such as regulating gene transcription, silencing target gene expression, and affecting protein translation. MicroRNAs also have various pharmacological activities, such as regulating cell proliferation, apoptosis, and metabolic processes. It is noteworthy that many studies in recent years have also proved that microRNAs play a role in atherosclerosis.

Methods

To summarize the functions of microRNAs in atherosclerosis, we reviewed all relevant articles published in the PubMed database before June 2022, with keywords "atherosclerosis," "microRNA," "endothelial cells," "vascular smooth muscle cells," "macrophages," and "cholesterol homeostasis," briefly summarized a series of research progress on the function of microRNAs in endothelial cells, vascular smooth muscle cells, and macrophages and atherosclerosis. Results and Conclusion. In general, the expression levels of some microRNAs changed significantly in different stages of atherosclerosis pathogenesis; therefore, MicroRNAs may become new diagnostic biomarkers for atherosclerosis. In addition, microRNAs are also involved in the regulation of core processes such as endothelial dysfunction, plaque formation and stabilization, and cholesterol metabolism, which also suggests the great potential of microRNAs as a therapeutic target.

Children with Chronic Immune Thrombocytopenia Exhibit High Expression of Human Endogenous Retroviruses TRIM28 and SETDB1

Chronic immune thrombocytopenia (CITP) is an autoimmune disease whose underlying biologic mechanisms remain elusive. Human endogenous retroviruses (HERVs) derive from ancestral infections and constitute about 8% of our genome. A wealth of clinical and experimental studies highlights their pivotal pathogenetic role in autoimmune diseases. Epigenetic mechanisms, such as those modulated by TRIM28 and SETDB1, are involved in HERV activation and regulation of immune response. We assessed, through a polymerase chain reaction real-time Taqman amplification assay, the transcription levels of pol genes of HERV-H, HERV-K, and HERV-W; env genes of Syncytin (SYN)1, SYN2, and HERV-W; as well as TRIM28 and SETDB1 in whole blood from 34 children with CITP and age-matched healthy controls (HC). The transcriptional levels of all HERV sequences, with the exception of HERV-W-env, were significantly enhanced in children with CITP as compared to HC. Patients on eltrombopag treatment exhibited lower expression of SYN1, SYN2, and HERV-W-env as compared to untreated patients. The mRNA concentrations of TRIM28 and SETDB1 were significantly higher and were positively correlated with those of HERVs in CITP patients. The over-expressions of HERVs and TRIM28/SETDB1 and their positive correlations in patients with CITP are suggestive clues of their contribution to the pathogenesis of the disease and support innovative interventions to inhibit HERV and TRIM28/SETDB1 expressions in patients unresponsive to standard therapies.

miR-4482 and miR-3912 aim for 3'UTR of ERG mRNA in prostate cancer

Ets-related gene (ERG) is overexpressed as a fusion protein in prostate cancer. During metastasis, the pathological role of ERG is associated with cell proliferation, invasion, and angiogenesis. Here, we hypothesized that miRNAs regulate ERG expression through its 3'UTR. Several bioinformatics tools were used to identify miRNAs and their binding sites on 3'UTR of ERG. The selected miRNAs expression was analyzed in prostate cancer samples by qPCR. The miRNAs overexpression was induced in prostate cancer cells (VCaP) to analyze ERG expression. Reporter gene assay was performed to evaluate the ERG activity in response to selected miRNAs. The expression of ERG downstream target genes was also investigated through qPCR after miRNAs overexpression. To observe the effects of selected miRNAs on cell proliferation and migration, scratch assay was performed to calculate the cell migration rate. miR-4482 and miR-3912 were selected from bioinformatics databases. miR-4482 and -3912 expression were decreased in prostate cancer samples, as compared to controls (p<0.05 and p<0.001), respectively. Overexpression of miR-4482 and miR-3912 significantly reduced ERG mRNA (p<0.001 and p<0.01), respectively) and protein (p<0.01) in prostate cancer cells. The transcriptional activity of ERG was significantly reduced (p<0.01) in response to miR-4482 and-3912. ERG angiogenic targets and cell migration rate was also reduced significantly (p<0.001) after miR-4482 and -3912 over-expression. This study indicates that miR-4482 and -3912 can suppress the ERG expression and its target genes, thereby, halt prostate cancer progression. These miRNAs may be employed as a potential therapeutic target for the miRNA-based therapy against prostate cancer.

Predictor Factors for Chronicity in Immune Thrombocytopenic Purpura in Children

(1) Background: Immune thrombocytopenia (ITP) is an acute autoimmune blood disorder that is the main cause of thrombocytopenia in children. It is characterized by a decrease in platelets below 100 × 10⁹/L, and limited evolution with severe complications such as intracranial hemorrhage. The chronic form is defined by the persistence of thrombocytopenia more than 12 months after diagnosis. (2) Methods: We performed a retrospective study over a period of 10 years (1 January 2011-31 December 2020) at the Emergency Clinical Hospital for Children "Sf. Maria", Iasi. The aim of the study was to describe the clinical characteristics and to determine the prognostic factors in immune thrombocytopenia in children. (3) Results: In this study we included 271 children with ITP, comprising 123 females (45.4%) and 148 males (54.6%). The remission rate was higher in males, being 68.9% compared to 56.1% in females. Children with ITP under 9 years of age had a higher remission rate. Children with a platelet count > 10 × 10⁹/L at diagnosis had a higher likelihood-of-remission rate compared to patients who presented initial platelet count below this value. (4) Conclusions: The risk factors highly suggestive for chronicity are: age at diagnosis, female sex, and the number of platelets at the onset of the disease.

Regulatory factors involved in Th17/Treg cell balance of immune thrombocytopenia

Immune thrombocytopenia is a common heterogeneous autoimmune disease that is characterized by decreasing peripheral blood platelet counts and increasing risk of bleeding. Studies have shown that an imbalance between T helper 17 (Th17) and Regulatory T (Treg) cells differentiated from CD4+T-cells is a key factor influencing the development and pathogenesis of immune thrombocytopenia. Th17 cells promote the development of chronic inflammatory disorders and induce autoimmune diseases, whereas Treg cells regulate immune homeostasis and prevent autoimmune diseases. Several regulators affecting the production and maintenance of these cells are also essential for proper regulation of Th17/Treg balance; these regulatory factors include cell surface proteins, miRNAs, and cytokine signaling. In this review, we focus on the function and role of balance between Th17 and Treg cells in immune thrombocytopenia, the regulatory factors, and therapeutic goals of this balance in immune thrombocytopenia.

Novel Biomarkers for Diagnosis and Monitoring of Immune Thrombocytopenia

Lower-than-normal platelet counts are a hallmark of the acquired autoimmune illness known as immune thrombocytopenia, which can affect both adults and children. Immune thrombocytopenia patients' care has evolved significantly in recent years, but the disease's diagnosis has not, and it is still only clinically achievable with the elimination of other causes of thrombocytopenia. The lack of a valid biomarker or gold-standard diagnostic test, despite ongoing efforts to find one, adds to the high rate of disease misdiagnosis. However, in recent years, several studies have helped to elucidate a number of features of the disease's etiology, highlighting how the platelet loss is not only caused by an increase in peripheral platelet destruction but also involves a number of humoral and cellular immune system effectors. This made it possible to identify the role of immune-activating substances such cytokines and chemokines, complement, non-coding genetic material, the microbiome, and gene mutations. Furthermore, platelet and megakaryocyte immaturity indices have been emphasized as new disease markers, and prognostic signs and responses to particular types of therapy have been suggested. Our review's goal was to compile information from the literature on novel immune thrombocytopenia biomarkers, markers that will help us improve the management of these patients.