STAT5: From Pathogenesis Mechanism to Therapeutic Approach in Acute Leukemia

Cognitive performance and brain volume among survivors of pediatric hematological malignancies: a case-control study

BACKGROUND

Cognitive dysfunction may be one of the hazardous late effects among survivors of pediatric hematological malignancies. Our study aimed to explore cognitive performance and assess the global and regional brain volume changes in survivors of hematological malignancies.

METHODS

This case-control study was conducted on 68 survivors of hematological malignancies, with a median follow-up period of 2 years (ranging from 1 to 6.2 years). Stanford-Binet Test was used for cognitive assessment. A quantitative volumetric assessment of the brain was done using the NeuroQuant Brain Magnetic Resonance. Age and sex-matched 68 children were selected as a comparison group.

RESULTS

Cancer survivors showed significantly lower levels of IQ and their subtests than the control group. Global brain atrophy was observed in the majority of the survivors. Many risk factors significantly affected different IQ subtests, such as radiotherapy (RTH), high cumulative doses of methotrexate (MTX), and prednisone. At the same time, low white matter volume (WMV) was observed with higher cumulative doses of MTX and anthracyclines.

CONCLUSIONS

Hematological malignancies have a negative impact on cognition. Neurocognitive impairment and related brain changes were evident in those who received RTH, HDMTX, or high cumulative doses of steroids.

The association between primary Sjogren's syndrome and non-Hodgkin's lymphoma: a systematic review and meta-analysis of cohort studies

Primary Sjögren's syndrome (pSS), a chronic autoimmune condition, has been associated with an increased risk of several cancers. This study aims to delve into the relationship between pSS and the potential development of non-Hodgkin's lymphoma (NHL) utilizing an in-depth systematic review and meta-analysis approach. To thoroughly explore the topic, we conducted a thorough examination of the literature, drawing from reputable databases such as ProQuest, PubMed, Web of Science, Cochrane, and Google Scholar. Our data collection spanned until February 8, 2024, with no time limitation. Data were analyzed with Stata 14 software at a significance threshold of p < 0.05. We examined 15 cohort studies encompassing a total of 50,308 individuals from 1997 to 2023. The findings revealed a substantial link between pSS and the risk of NHL, evident across all demographics. Specifically, the standardized incidence ratio (SIR) was generally 8.78 (95% CI 5.51, 13.99), with similar trends observed in both men (SIR, 6.29; 95% CI 1.93, 20.51) and women (SIR, 9.60; 95% CI 5.89, 15.63). Additionally, the SIR (10.50 (95% CI 7, 15.75)), HR (2.82 (95% CI 1.28, 6.18)), and OR (10.50 (95% CI 3.04, 36.28)) indices further supported this association. Furthermore, the risk of non-NHL associated with pSS was noticeable across different age groups of 40-49 years (SIR, 30.13; 95% CI 14.62, 62.08), 50-59 years (SIR, 9.12; 95% CI 5.13, 16.19), and 60-69 years (SIR, 9; 95% CI 4.68, 17.32). pSS substantively augments the likelihood of NHL manifestation. It notably impacts females and those in earlier stages of adulthood with more acuity than males and older cohorts.

Interplay between signal transducers and activators of transcription (STAT) proteins and cancer: involvement, therapeutic and prognostic perspective

Signal transducers and activators of transcription or STAT are proteins that consist of various transcription factors that are responsible for activating genes regarding cell proliferation, differentiation, and apoptosis. They commonly activate several cytokine, growth, or hormone factors via the JAK-STAT signaling pathway by tyrosine phosphorylation which are responsible for giving rise to numerous immune responses. Mutations within the Janus-Kinases (JAKs) or the STATs can set off the commencement of various malfunctions of the immune system of the body; carcinogenesis being an inevitable outcome. STATs are known to act as both oncogenes and tumor suppressor genes which makes it a hot topic of investigation. Various STATs related mechanisms are currently being investigated to analyze its potential of serving as a therapeutic base for numerous immune diseases and cancer; a deeper understanding of the molecular mechanisms involved in the signaling pathways can contribute to the same. This review will throw light upon each STAT member in causing cancer malignancies by affecting subsequent signaling pathways and its genetic and epigenetic associations as well as various inhibitors that could be used to target these pathways thereby devising new treatment options. The review will also focus upon the therapeutic advances made in cancers that most commonly affect people and discuss how STAT genes are identified as prognostic markers.

Micheliolide exerts effects in myeloproliferative neoplasms through inhibiting STAT3/5 phosphorylation via covalent binding to STAT3/5 proteins

Ruxolitinib is a cornerstone of management for some subsets of myeloproliferative neoplasms (MPNs); however, a considerable number of patients respond suboptimally. Here, we evaluated the efficacy of micheliolide (MCL), a natural guaianolide sesquiterpene lactone, alone or in combination with ruxolitinib in samples from patients with MPNs, JAK2V617F-mutated MPN cell lines, and a Jak2V617F knock-in mouse model. MCL effectively suppressed colony formation of hematopoietic progenitors in samples from patients with MPNs and inhibited cell growth and survival of MPN cell lines in vitro. Co-treatment with MCL and ruxolitinib resulted in greater inhibitory effects compared with treatment with ruxolitinib alone. Moreover, dimethylaminomicheliolide (DMAMCL), an orally available derivative of MCL, significantly increased the efficacy of ruxolitinib in reducing splenomegaly and cytokine production in Jak2V617F knock-in mice without evident effects on normal hematopoiesis. Importantly, MCL could target the Jak2V617F clone and reduce mutant allele burden in vivo. Mechanistically, MCL can form a stable covalent bond with cysteine residues of STAT3/5 to suppress their phosphorylation, thus inhibiting JAK/STAT signaling. Overall, these findings suggest that MCL is a promising drug in combination with ruxolitinib in the setting of suboptimal response to ruxolitinib.

Transforming Growth Factor-Beta (TGF-β) Signaling in Cancer-A Betrayal Within

A ubiquitously expressed cytokine, transforming growth factor-beta (TGF-β) plays a significant role in various ongoing cellular mechanisms. The gain or loss-of-function of TGF-β and its downstream mediators could lead to a plethora of diseases includes tumorigenesis. Specifically, at the early onset of malignancy TGF-β act as tumour suppressor and plays a key role in clearing malignant cells by reducing the cellular proliferation and differentiation thus triggers the process of apoptosis. Subsequently, TGF-β at an advanced stage of malignancy promotes tumorigenesis by augmenting cellular transformation, epithelial-mesenchymal-transition invasion, and metastasis. Besides playing the dual roles, depending upon the stage of malignancy, TGF-β also regulates cell fate through immune and stroma components. This oscillatory role of TGF-β to fight against cancer or act as a traitor to collaborate and crosstalk with other tumorigenic signaling pathways and its betrayal within the cell depends upon the cellular context. Therefore, the current review highlights and understands the dual role of TGF-β under different cellular conditions and its crosstalk with other signaling pathways in modulating cell fate.

Genetic factors in treatment-related cardiovascular complications in survivors of childhood acute lymphoblastic leukemia

Aim: Cardiovascular disease represents one of the main causes of secondary morbidity and mortality in patients with childhood cancer. Patients & methods: To further address this issue, we analyzed cardiovascular complications in relation to common and rare genetic variants derived through whole-exome sequencing from childhood acute lymphoblastic leukemia survivors (PETALE cohort). Results: Significant associations were detected among common variants in the TTN gene, left ventricular ejection fraction (p ≤ 0.0005), and fractional shortening (p ≤ 0.001). Rare variants enrichment in the NOS1, ABCG2 and NOD2 was observed in relation to left ventricular ejection fraction, and in NOD2 and ZNF267 genes in relation to fractional shortening. Following stratification according to risk groups, the modulatory effect of rare variants was additionally found in the CBR1, ABCC5 and AKR1C3 genes. None of the associations was replicated in St-Jude Lifetime Cohort Study. Conclusion: Further studies are needed to confirm whether the described genetic markers may be useful in identifying patients at increased risk of these complications.

Mechanism of Human Telomerase Reverse Transcriptase (hTERT) Regulation and Clinical Impacts in Leukemia

The proliferative capacity and continuous survival of cells are highly dependent on telomerase expression and the maintenance of telomere length. For this reason, elevated expression of telomerase has been identified in virtually all cancers, including leukemias; however, it should be noted that expression of telomerase is sometimes observed later in malignant development. This time point of activation is highly dependent on the type of leukemia and its causative factors. Many recent studies in this field have contributed to the elucidation of the mechanisms by which the various forms of leukemias increase telomerase activity. These include the dysregulation of telomerase reverse transcriptase (TERT) at various levels which include transcriptional, post-transcriptional, and post-translational stages. The pathways and biological molecules involved in these processes are also being deciphered with the advent of enabling technologies such as next-generation sequencing (NGS), ribonucleic acid sequencing (RNA-Seq), liquid chromatography-mass spectrometry (LCMS/MS), and many others. It has also been established that TERT possess diagnostic value as most adult cells do not express high levels of telomerase. Indeed, studies have shown that prognosis is not favorable in patients who have leukemias expressing high levels of telomerase. Recent research has indicated that targeting of this gene is able to control the survival of malignant cells and therefore offers a potential treatment for TERT-dependent leukemias. Here we review the mechanisms of hTERT regulation and deliberate their association in malignant states of leukemic cells. Further, we also cover the clinical implications of this gene including its use in diagnostic, prognostic, and therapeutic discoveries.

Evaluation of microRNA-223 and microRNA-125a expression association with STAT3 and Bcl2 genes in blood leukocytes of CLL patients: a case-control study

OBJECTIVE

In chronic lymphocytic leukemia (CLL), lack of expression or dysregulation of some special miRs disrupts apoptosis of malignant cells; thereby miR expression can enhance cell proliferation, disease progression and decrease patient survival.

RESULTS

30 CLL patients and 20 healthy individuals participated in the study. RNA was extracted to evaluate the expression of miR-125, miR-223, BCL-2 and signal transducer and transcription 3 activator (STAT3) genes; quantitative Real Time- PCR (Q-RT-PCR) was performed. MiR-125a and miR-223 expression decreased in the patients compared to the control group (P-Value:0.001). BCL-2 and STAT3 which are the target genes of these two miRs, showed increased expression, in the patients compared to the control subjects (P-Value: 0.001 and P-Value: 0.64 respectively). A significant reverse relationship was found between miR-125a and BCl-2 expression and WBC count. Significantly, miR-223 expression was associated with smoking in patients (P-Value: 0.007). Also, these miRs may have regulatory effects by controlling white blood cell (WBC) production based on the inverse correlation with WBC count and hemoglobin (Hb) concentration. Finally, miR-223 can be used as a prognostic factor in CLL patients; miR-125a may be useful for evaluating the therapeutic approaches based on the inverse link with BCl-2.