A p53-JAK-STAT connection involved in myeloproliferative neoplasm pathogenesis and progression to secondary acute myeloid leukemia

A comparative analysis of the clinical and genetic profiles of blast phase BCR::ABL1-negative myeloproliferative neoplasm and acute myeloid leukemia, myelodysplasia-related

INTRODUCTION

The classic Philadelphia chromosome-negative myeloproliferative neoplasms (Ph (-) MPNs), have variable potential for progression to the blast phase (MPN-BP) of the disease. Except initiated by distinct driver mutations, MPN-BP frequently carry similar genetic abnormalities defining acute myeloid leukemia myelodysplasia-related (AML-MR). Because of dissimilar initial pathogenesis, MPN-BP and AML-MR are retained under different disease categories. To determine if separately classifying these entities is justified, we compare MPN-BP with AML-MR patients based on mutational landscape and clinical parameters.

METHODS

104 MPN-BP patients and 145 AML-MR patients were identified with available clinical, cytogenetic, and genetic data.

RESULTS

AML-MR patients presented with a higher blast count (median, 51% vs. 30%) while MPN-BP patients had higher WBC counts, platelet counts and bone marrow cellularity (all p<0.0001). Patients with MPN-BP showed similar genetic mutations with similar mutation pattern (functional domain, hotspot and locus involved by the mutations) but a different mutation rate from AML-MR, with more frequent JAK2, CALR, MPL, ASXL1, IDH2, SETBP1 and SRSF2 mutations and less frequent TP53 and DNMT3A mutations. The overall survival (OS) of MPN-BP (OS post-BP-progression) is comparable to that of AML-MR (median OS, 9.5 months vs. 13.1 months, p=0.20). In addition, the subgroups of MPN-BP show similar OS as AML-MR. When harboring certain mutation such as TP53, ASXL1, DNMT3A, TET2, RUNX1, IDH1, IDH2, EZH2, U2AF1, BCOR and SRSF2, MPN-BP and AML-MR patients carrying the same somatic mutation show no difference in OS.

CONCLUSION

MPN-BP and AML-MR harbor similar somatic mutations and clinical outcomes, suggesting a unified clinical disease entity.

The ubiquitin-proteasome system in the regulation of tumor dormancy and recurrence

Tumor recurrence is a mechanism triggered in sparse populations of cancer cells that usually remain in a quiescent state after strict stress and/or therapeutic factors, which is affected by a variety of autocrine and microenvironmental cues. Despite thorough investigations, the biology of dormant and/or cancer stem cells is still not fully elucidated, as for the mechanisms of their reawakening, while only the major molecular patterns driving the relapse process have been identified to date. These molecular patterns profoundly interfere with the elements of cellular proteostasis systems that support the efficiency of the recurrence process. As a major proteostasis machinery, we review the role of the ubiquitin-proteasome system (UPS) in tumor cell dormancy and reawakening, devoting particular attention to the functions of its components, E3 ligases, deubiquitinating enzymes and proteasomes in cancer recurrence. We demonstrate how UPS components functionally or mechanistically interact with the pivotal proteins implicated in the recurrence program and reveal that modulators of the UPS hold promise to become an efficient adjuvant therapy for eradicating refractory tumor cells to impede tumor relapse.

The molecular mechanisms underlying the regeneration process in the earthworm, Perionyx excavatus exhibit indications of apoptosis-induced compensatory proliferation (AICP)

Regeneration is a multifaceted biological phenomenon that necessitates the intricate orchestration of apoptosis, stem cells, and immune responses, culminating in the regulation of apoptosis-induced compensatory proliferation (AICP). The AICP context of research is observed in many animal models like in Hydra, Xenopus, newt, Drosophila, and mouse but so far not reported in earthworm. The earthworm Perionyx excavatus is used in the present study to understand the relationship between AICP-related protein expression and regeneration success in different conditions (normal regeneration and abnormal multiple bud formation). Initially, the worms are amputated into five equal portions and it is revealed that regeneration in P. excavatus is clitellum independent and it gives more preference for anterior regeneration (regrowth of head portion) than for posterior regeneration (regrowth of tail portion). The posterior segments of the worm possess enormous regeneration ability but this is lacking in anterior segments. Alkaline phosphate, a stem cell marker, shows strong signals throughout all the posterior segments but it decreases in the initial 1st to 15th anterior segments which lack the regeneration ability. While regenerating normally, it was suggested that the worm follow AICP principles. This is because there was increased expression of apoptosis signals throughout the regeneration process along with constant expression of stem cell proliferation response together with cellular proliferation. In amputated posterior segments maintained in vitro, the apoptosis signals were extensively detected on the 1st day. However, on the 4th and 6th days, caspase-3 and H2AX expression are significantly suppressed, which may eventually alter the Wnt3a and histone H3 patterns that impair the AICP and result in multiple bud formation. Our results suggest that AICP-related protein expression pattern is crucial for initiating proper regeneration.

Myeloproliferative Neoplasms: Diseases Mediated by Chronic Activation of Signal Transducer and Activator of Transcription (STAT) Proteins

Myeloproliferative neoplasms (MPNs) are hematopoietic diseases characterized by the clonal expansion of single or multiple lineages of differentiated myeloid cells that accumulate in the blood and bone marrow. MPNs are grouped into distinct categories based on key clinical presentations and distinctive mutational hallmarks. These include chronic myeloid leukemia (CML), which is strongly associated with the signature BCR::ABL1 gene translocation, polycythemia vera (PV), essential thrombocythemia (ET), and primary (idiopathic) myelofibrosis (PMF), typically accompanied by molecular alterations in the JAK2, MPL, or CALR genes. There are also rarer forms such as chronic neutrophilic leukemia (CNL), which involves mutations in the CSF3R gene. However, rather than focusing on the differences between these alternate disease categories, this review aims to present a unifying molecular etiology in which these overlapping diseases are best understood as disruptions of normal hematopoietic signaling: specifically, the chronic activation of signaling pathways, particularly involving signal transducer and activator of transcription (STAT) transcription factors, most notably STAT5B, leading to the sustained stimulation of myelopoiesis, which underpins the various disease sequalae.

Impact of genetic patterns on sorafenib efficacy in patients with FLT3-ITD acute myeloid leukemia undergoing allogeneic hematopoietic stem cell transplantation: a multi-center, cohort study

Sorafenib therapy improves overall survival (OS) in patients with FLT3 internal tandem duplication (ITD) acute myeloid leukemia (AML) undergoing allogeneic hematopoietic stem cell transplantation. We explored the efficacy of sorafenib therapy in this population with different concomitant genetic patterns. In this multi-center, cohort study, we enrolled patients with FLT3-ITD AML undergoing allogenic hematopoietic cell transplantation. Patients with sorafenib maintenance post-transplantation for at least four weeks were allocated to the sorafenib group, and otherwise to the control group. Endpoints were OS, disease-free survival, and relapse for the whole cohort and OS for genetic pattern subgroups. Among 613 patients enrolled, 275 were in the sorafenib and 338 the control group. Median follow-up was 36.5 (interquartile range (IQR), 25.2-44.7) months post-transplantation. The 3-year OS post-transplantation was 79.6% (95% confidential interval (CI) 74.8%-84.6%) and 65.2% (95% CI 60.3%-70.6%) (Hazard ratio (HR) 0.50, 95% CI 0.37-0.69; P < 0.0001) in both groups. Sorafenib maintenance post-transplantation improved OS in the favorable (HR 0.33, 95% CI 0.14-0.77; P = 0.011) and adverse (HR 0.56, 95% CI 0.33-0.93; P = 0.026) ELN 2017 risk subgroups. Patients with mutated NPM1, DNMT3A, co-occurring NPM1/DNMT3A, "activated signaling" and "DNA methylation" genes benefited in OS from sorafenib maintenance, while those carrying CEBPA, "tumor suppressors" and "myeloid transcription factors" genes did not. Patients with FLT3-ITDhigh and FLT3-ITDlow AML both benefited in OS from sorafenib maintenance. Our results identify the response of genetic patterns to sorafenib maintenance, providing new viewpoints for the optimal use of sorafenib in FLT3-ITD AML in the transplantation setting.

A gene pathway enrichment method based on improved TF-IDF algorithm

Gene pathway enrichment analysis is a widely used method to analyze whether a gene set is statistically enriched on certain biological pathway network. Current gene pathway enrichment methods commonly consider local importance of genes in pathways without considering the interactions between genes. In this paper, we propose a gene pathway enrichment method (GIGSEA) based on improved TF-IDF algorithm. This method employs gene interaction data to calculate the influence of genes based on the local importance in a pathway as well as the global specificity. Computational experiment result shows that, compared with traditional gene set enrichment analysis method, our proposed method in this paper can find more specific enriched pathways related to phenotype with higher efficiency.

Biological drivers of clinical phenotype in myelofibrosis

Myelofibrosis (MF) is a myeloproliferative disorder that exhibits considerable biological and clinical heterogeneity. At the two ends of the disease spectrum are the myelodepletive or cytopenic phenotype and the myeloproliferative phenotype. The cytopenic phenotype has a high prevalence in primary MF (PMF) and is characterized by low blood counts. The myeloproliferative phenotype is typically associated with secondary MF (SMF), mild anemia, minimal need for transfusion support, and normal to mild thrombocytopenia. Differences in somatic driver mutations and allelic burden, as well as the acquisition of non-driver mutations further influences these phenotypic differences, prognosis, and response to therapies such as JAK2 inhibitors. The outcome of patients with the cytopenic phenotype are comparatively worse and frequently pose a challenge to treat given the inherent exacerbation of cytopenias. Recent data indicate that an innate immune deregulated state that hinges on the myddosome-IRAK-NFκB axis favors the cytopenic myelofibrosis phenotype and offers opportunity for novel treatment approaches. We will review the biological and clinical features of the MF disease spectrum and associated treatment considerations.

Involvement of caveolin-1 in skin diseases

The skin is the outermost layer and largest organ in the human body. Since the skin interfaces with the environment, it has a variety of roles, including providing a protective barrier against external factors, regulating body temperature, and retaining water in the body. It is also involved in the immune system, interacting with immune cells residing in the dermis. Caveolin-1 (CAV-1) is essential for caveolae formation and has multiple functions including endocytosis, lipid homeostasis, and signal transduction. CAV-1 is known to interact with a variety of signaling molecules and receptors and may influence cell proliferation and migration. Several skin-related disorders, especially those of the inflammatory or hyperproliferative type such as skin cancers, psoriasis, fibrosis, and wound healing, are reported to be associated with aberrant CAV-1 expression. In this review, we have explored CAV-1 involvement in skin physiology and skin diseases.

Long-term exposure to low levels of okadaic acid accelerates cell cycle progression in colonic epithelial cells via p53 and Jak/Stat3 signaling pathways

As a major component of diarrheic shellfish poisoning (DSP) toxins, okadaic acid (OA) is widely distributed worldwide, and causes a series of serious public health problems. In colon tissue, previous studies have shown that high doses of OA can affect various intracellular processes, including destroy intercellular communication at gap junctions, induce cell apoptosis and trigger cell cycle arrest. However, there is a scarcity of studies on the effect and mechanism of action of low doses of OA in colonic tissues. In this study, we observed that exposure to low levels of OA altered cell cycle progression in vitro and in vivo. Investigation of the underlying mechanism revealed that OA induced alterations in the cell cycle by inhibiting the p53 signaling pathway or inducing the Jak/Stat3 signaling pathway. In conclusion, this study provides novel insights into the effect and mechanism underlying long-term exposure to low levels of OA.

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Long-term exposure to low levels of OA accelerates cell cycles in vitro and in vivo

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OA induced changes in cell cycle by inhibiting the p53 signaling pathway

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OA induced changes in cell cycle by inducing the Jak/Stat3 signaling pathway

The possible involvement of circRNA DMNT1/p53/JAK/STAT in gestational diabetes mellitus and preeclampsia

Circular RNA (circRNA) plays an important role in biological processes of gestational diabetes mellitus (GDM) and preeclampsia (PE). However, the mechanisms for circRNA DMNT1 (circ-DMNT1) in GDM and PE remain unclarified. The expression levels of circ-DMNT1 and p53 in GDM and PE were quantified by quantitative real-time polymerase chain reaction (qRT-PCR) and western blot analysis. When the expression of circ-DMNT1 or p53 was abnormal, cell counting kit-8 (CCK-8) assay, bromodeoxyuridine (BrdU) staining, flow cytometry, cell scratch, and Transwell assays were used to assess cell viability, proliferation, cell cycle, apoptosis, migration, and invasion of trophoblast cells, respectively. Subsequently, the binding relationship between circ-DMNT1 and p53 was verified by RNA pull-down and RIP analysis, followed by the determination of JAK/STAT pathway-related protein expression levels using western blot analysis. Both circ-DMNT1 and p53 were highly expressed in GDM and PE. Upregulation of circ-DMNT1 or p53 inhibited trophoblast cell viability, proliferation, migration, and invasion, meanwhile promoting cell apoptosis but blocking cell cycle progression. However, downregulation of circ-DMNT1 or p53 induced trophoblast cell survival. In GDM and PE, circ-DMNT1 activated the JAK/STAT pathway by binding to p53, which resulted in increased expression levels of p-JAK and p-STAT. The results suggested that circ-DMNT1 was involved in the deterioration of GDM and PE, possibly through inducing p53 expression and activating the JAK/STAT signaling pathway.

The role of E2A in ATPR-induced cell differentiation and cycle arrest in acute myeloid leukaemia cells

Acute myeloid leukaemia (AML) is a biologically heterogeneous disease with an overall poor prognosis; thus, novel therapeutic approaches are needed. Our previous studies showed that 4-amino-2-trifluoromethyl-phenyl retinate (ATPR), a new derivative of all-trans retinoic acid (ATRA), could induce AML cell differentiation and cycle arrest. The current study aimed to determine the potential pharmacological mechanisms of ATPR therapies against AML. Our findings showed that E2A was overexpressed in AML specimens and cell lines, and mediate AML development by inactivating the P53 pathway. The findings indicated that E2A expression and activity decreased with ATPR treatment. Furthermore, we determined that E2A inhibition could enhance the effect of ATPR-induced AML cell differentiation and cycle arrest, whereas E2A overexpression could reverse this effect, suggesting that the E2A gene plays a crucial role in AML. We identified P53 and c-Myc were downstream pathways and targets for silencing E2A cells using RNA sequencing, which are involved in the progression of AML. Taken together, these results confirmed that ATPR inhibited the expression of E2A/c-Myc, which led to the activation of the P53 pathway, and induced cell differentiation and cycle arrest in AML.

TGF-beta signaling in cancer radiotherapy

Transforming growth factor beta (TGF-β) plays key roles in regulating cellular proliferation and maintaining tissue homeostasis. TGF-β exerts tumor-suppressive effects in the early stages of carcinogenesis, but it also plays tumor-promoting roles in established tumors. Additionally, it plays a critical role in cancer radiotherapy. TGF-β expression or activation increases in irradiated tissues, and studies have shown that TGF-β plays dual roles in cancer radiosensitivity and is involved in ionizing radiation-induced fibrosis in different tumor microenvironments (TMEs). Furthermore, TGF-β promotes radioresistance by inducing the epithelial-mesenchymal transition (EMT), cancer stem cells (CSCs) and cancer-associated fibroblasts (CAFs), suppresses the immune system and facilitates cancer resistance. In particular, the links between TGF-β and the Janus kinase (JAK)/signal transducer and activator of transcription (STAT) axis play a critical role in cancer therapeutic resistance. Growing evidence has shown that TGF-β acts as a radiation protection agent, leading to heightened interest in using TGF-β as a therapeutic target. The future of anti-TGF-β signaling therapy for numerous diseases appears bright, and the outlook for the use of TGF-β inhibitors in cancer radiotherapy as TME-targeting agents is promising.

Targets in MPNs and potential therapeutics

Philadelphia-negative classical Myeloproliferative Neoplasms (MPNs), including Polycythemia Vera (PV), Essential Thrombocythemia (ET) and Primary Myelofibrosis (PMF), are clonal hemopathies that emerge in the hematopoietic stem cell (HSC) compartment. MPN driver mutations are restricted to specific exons (14 and 12) of Janus kinase 2 (JAK2), thrombopoietin receptor (MPL/TPOR) and calreticulin (CALR) genes, are involved directly in clonal myeloproliferation and generate the MPN phenotype. As a result, an increased number of fully functional erythrocytes, platelets and leukocytes is observed in the peripheral blood. Nevertheless, the complexity and heterogeneity of MPN clinical phenotypes cannot be solely explained by the type of driver mutation. Other factors, such as additional somatic mutations affecting epigenetic regulators or spliceosomes components, mutant allele burdens and modifiers of signaling by driver mutants, clonal architecture and the order of mutation acquisition, signaling events that occur downstream of a driver mutation, the presence of specific germ-line variants, the interaction of the neoplastic clone with bone marrow microenvironment and chronic inflammation, all can modulate the disease phenotype, influence the MPN clinical course and therefore, might be useful therapeutic targets.

Impacts of LOC105371267 Variants on Breast Cancer Susceptibility in Northern Chinese Han Females: A Population-Based Case-Control Study

Background

LOC105371267, also known as PR-lncRNA1, was reported to be a p53-regulated long noncoding RNA (lncRNA), which played an essential role in the pathogenesis of breast cancer (BC). We aimed to observe the potential association between LOC105371267 polymorphisms and BC risk in Northern Chinese Han females.

Methods

Totally, 555 healthy individuals and 561 patients with BC were recruited. Five candidate SNPs (rs6499221, rs3931698, rs8044565, rs3852740, and rs111577197) of LOC105371267 were genotyped with the Agena MassARRAY system. Odds ratio (OR) and 95% confidence intervals (CIs) were applied to evaluate the relationship of LOC105371267 genetic polymorphisms with BC susceptibility. Additionally, stratification analysis based on clinical features and haplotype analysis were also conducted. Finally, multifactor dimensionality reduction (MDR) analysis was performed to assess the SNP-SNP interaction among LOC105371267 variants, and false-positive report probability (FPRP) analysis was used to validate the result of this study.

Results

In this study, rs3931698 was a protective factor of BC in total (GG homozygote: OR = 0.30, 95% CI: 0.11–0.82, p=0.018; recessive model: OR = 0.30, 95% CI: 0.11–0.84, p=0.021). In stratification analysis based on the average age of 52 years and clinical characteristics (PR status, III-IV TNM stage), rs3931698 was also demonstrated to be associated with BC susceptibility. In addition, rs6499221 and rs3852740 were also associated with BC susceptibility among patients at age <52 years and patients with BC in a positive status. Thus, the haplotype analysis had a negative result for the incidence of BC (p > 0.05), and haplotype consisting of rs8044565 and rs111577197 was nonsignificantly associated with the BC risk. Finally, MDR and FPRP analyses also validated the result of this study.

Conclusion

Polymorphisms rs3931698, rs6499221, and rs3852740 of LOC105371267 were found to be associated with the risk of BC in total, and stratification analysis in the Northern Chinese Han females suggested that LOC105371267 variants might be helpful to predict BC progression.

Janus Kinases in Leukemia

Janus kinases (JAKs) transduce signals from dozens of extracellular cytokines and function as critical regulators of cell growth, differentiation, gene expression, and immune responses. Deregulation of JAK/STAT signaling is a central component in several human diseases including various types of leukemia and other malignancies and autoimmune diseases. Different types of leukemia harbor genomic aberrations in all four JAKs (JAK1, JAK2, JAK3, and TYK2), most of which are activating somatic mutations and less frequently translocations resulting in constitutively active JAK fusion proteins. JAKs have become important therapeutic targets and currently, six JAK inhibitors have been approved by the FDA for the treatment of both autoimmune diseases and hematological malignancies. However, the efficacy of the current drugs is not optimal and the full potential of JAK modulators in leukemia is yet to be harnessed. This review discusses the deregulation of JAK-STAT signaling that underlie the pathogenesis of leukemia, i.e., mutations and other mechanisms causing hyperactive cytokine signaling, as well as JAK inhibitors used in clinic and under clinical development.