miR-129 targets CDK1 and iASPP to modulate Burkitt lymphoma cell proliferation in a TAp63-dependent manner

CDK1 inhibitor RO-3306 enhances BTKi potency in diffuse large B-cell lymphoma by suppressing JAK2/STAT3 signaling

Diffuse large B-cell lymphoma (DLBCL) is the most common type of lymphoma in adults, which characterized by a high degree of heterogeneity in terms of clinical presentation, molecular phenotype, and genetic features. However, approximately 30 %-40 % of patients are refractory to standard chemotherapy, and their prognosis is poor. The emergence of small-molecule inhibitors, such as Bruton's tyrosine kinase inhibitors (BTKi), has greatly improved the treatment of DLBCL; however, drug resistance associated with small-molecule inhibitors has greatly limited their clinical application. In this study, we elucidated the principal genes influencing BTKi sensitivity in DLBCL and delineated the underlying mechanisms. This study identified cyclin-dependent kinase 1 (CDK1) as the central gene influencing BTKi sensitivity in DLBCL cells. The application of RO-3306 effectively promoted the growth and increased the apoptotic rate of DLBCL cells. Furthermore, RO-3306 increased the susceptibility of DLBCL cells to BTKis in both in vitro and xenograft experimental models. RNA-seq analyses suggested the potential modulation of the JAK2/STAT3 signaling cascade by RO-3306, a finding further confirmed by the diminished phosphorylation documented by western blotting. This study provides pivotal insights into the mechanisms governing BTKi sensitivity in DLBCL and potentially reveals new avenues for targeted therapeutic strategies.

Prognostic significance of CDK1 expression in diffuse large B-Cell lymphoma

BACKGROUND

Diffuse large B-cell lymphoma (DLBCL) is the most common lymphoma in adult, characterized by uncontrolled cell proliferation and strong aggressiveness. Previous studies have found that cyclin-dependent kinase 1(CDK1) are related to tumor growth and metastasis. However, the role of CDK1 in DLBCL is exclusive. This study investigated the clinical implications and expression of CDK1 in DLBCL.

METHODS

Gene expression data for healthy subjects were sourced from the Genotype-Tissue Expression repository. Clinical details and survival statistics of patients with DLBCL were obtained from the Gene Expression Omnibus archive (GSE10846). Patients were categorized based on CDK1 expression levels, and differences in clinical outcomes between the groups were examined. Univariate and multivariate Cox regression analyses were used to ascertain whether CDK1 expression independently predicted DLBCL prognosis. The protein expression of CDK1 was gauged by immunohistochemistry. Additionally, we investigated the effect of CDK1 inhibition on DLBCL cell growth and death using the Cell Counting Kit-8 and flow cytometry.

RESULTS

In the control group, CDK1 expression was predominantly observed in the hematopoietic and reproductive systems. CDK1 levels in patients with DLBCL were notably elevated compared with those in controls. Significant differences were noted in the lactate dehydrogenase ratio and overall survival based on CDK1 expression. Statistical analyses confirmed that CDK1 was an independent predictor of DLBCL outcomes. Elevated CDK1 protein levels were observed in a significant number of DLBCL samples, in contrast to normal lymph node samples from individuals without lymphoma. The inhibitor Ro-3306 curtails DLBCL cell growth and enhances cell death in vitro.

CONCLUSIONS

Elevated CDK1 levels are correlated with poor prognosis in patients with DLBCL.

A review on the role of cyclin dependent kinases in cancers

The Cyclin-dependent kinase (CDK) class of serine/threonine kinases has crucial roles in the regulation of cell cycle transition and is mainly involved in the pathogenesis of cancers. The expression of CDKs is controlled by a complex regulatory network comprised of genetic and epigenetic mechanisms, which are dysregulated during the progression of cancer. The abnormal activation of CDKs results in uncontrolled cancer cell proliferation and the induction of cancer stem cell characteristics. The levels of CDKs can be utilized to predict the prognosis and treatment response of cancer patients, and further understanding of the function and underlying mechanisms of CDKs in human tumors would pave the way for future cancer therapies that effectively target CDKs. Defects in the regulation of cell cycle and mutations in the genes coding cell-cycle regulatory proteins lead to unrestrained proliferation of cells leading to formation of tumors. A number of treatment modalities have been designed to combat dysregulation of cell cycle through affecting expression or activity of CDKs. However, effective application of these methods in the clinical settings requires recognition of the role of CDKs in the progression of each type of cancer, their partners, their interactions with signaling pathways and the effects of suppression of these kinases on malignant features. Thus, we designed this literature search to summarize these findings at cellular level, as well as in vivo and clinical levels.

ΔNp63α promotes Epstein-Barr virus latency in undifferentiated epithelial cells

Epstein-Barr virus (EBV) is a human herpesvirus that causes infectious mononucleosis and contributes to both B-cell and epithelial-cell malignancies. EBV-infected epithelial cell tumors, including nasopharyngeal carcinoma (NPC), are largely composed of latently infected cells, but the mechanism(s) maintaining viral latency are poorly understood. Expression of the EBV BZLF1 (Z) and BRLF1 (R) encoded immediate-early (IE) proteins induces lytic infection, and these IE proteins activate each other's promoters. ΔNp63α (a p53 family member) is required for proliferation and survival of basal epithelial cells and is over-expressed in NPC tumors. Here we show that ΔNp63α promotes EBV latency by inhibiting activation of the BZLF1 IE promoter (Zp). Furthermore, we find that another p63 gene splice variant, TAp63α, which is expressed in some Burkitt and diffuse large B cell lymphomas, also represses EBV lytic reactivation. We demonstrate that ΔNp63α inhibits the Z promoter indirectly by preventing the ability of other transcription factors, including the viral IE R protein and the cellular KLF4 protein, to activate Zp. Mechanistically, we show that ΔNp63α promotes viral latency in undifferentiated epithelial cells both by enhancing expression of a known Zp repressor protein, c-myc, and by decreasing cellular p38 kinase activity. Furthermore, we find that the ability of cis-platinum chemotherapy to degrade ΔNp63α contributes to the lytic-inducing effect of this agent in EBV-infected epithelial cells. Together these findings demonstrate that the loss of ΔNp63α expression, in conjunction with enhanced expression of differentiation-dependent transcription factors such as BLIMP1 and KLF4, induces lytic EBV reactivation during normal epithelial cell differentiation. Conversely, expression of ΔNp63α in undifferentiated nasopharyngeal carcinoma cells and TAp63α in Burkitt lymphoma promotes EBV latency in these malignancies.

Targeting ZEB2 By microRNA-129 In Non-Small Cell Lung Cancer Suppresses Cell Proliferation, Invasion And Migration Via Regulating Wnt/β-Catenin Signaling Pathway And Epithelial-Mesenchymal Transition

Introduction

Non-small cell lung cancer (NSCLC) is a common cause of deaths all over the world. Emerging evidence has indicated that microRNA (miR) play key roles in NSCLC progression. We aimed to determine the functions of miR-129 in NSCLC. miR-129 was dramatically downregulated in NSCLC tissue samples and cells. The decreased miR-129 was found to be associated with poorer prognosis and malefic phenotype of NSCLC patients. We demonstrated that miR-129 upregulation could inhibit NSCLC cell growth. Furthermore, we also sought the molecular mechanism by which miR-129 repressed NSCLC development.

Methods

QRT-PCR was applied to detect the expressions of miR-129 in 51 pairs of NSCLC tissue samples. We further performed the Kaplan–Meier analysis to determine the association between miR-129 expressions and the survival rate of NSCLC patients. We then measured the expression levels of miR-129 in NSCLC cell lines. After that, MTT assays were performed to determine the influence of miR-129 on A549 cell proliferation. Transwell assay was then conducted to explore the biological functions of miR-129 in invasion and migration of NSCLC cells.

Results

Results showed that ZEB2 was directly targeted by miR-129 in NSCLC cell lines. Moreover, miR-129 restoration could inhibit EMT and Wnt/β-catenin in NSCLC cell lines.

Conclusion

In short, all these results indicated that miR-129/ZEB2 axis maybe a useful diagnostic and prognostic biomarker for NSCLC treatment.