Regulation of Hippo-YAP signaling by insulin-like growth factor-1 receptor in the tumorigenesis of diffuse large B-cell lymphoma

FAT1 inhibits the proliferation of DLBCL cells via increasing the m6A modification of YAP1 mRNA

Emerging evidence shows that FAT atypical cadherin 1 (FAT1) mutations occur in lymphoma and are associated with poorer overall survival. Considering that diffuse large B cell lymphoma (DLBCL) is the category of lymphoma with the highest incidence rate, this study aims to explore the role of FAT1 in DLBCL. The findings demonstrate that FAT1 inhibits the proliferation of DLBCL cell lines by downregulating the expression of YAP1 rather than by altering its cellular localization. Mechanistic analysis via meRIP-qPCR/luciferase reporter assays showed that FAT1 increases the m6A modification of YAP1 mRNA 3'UTR and the subsequent binding of heterogeneous nuclear ribonucleoprotein D (HNRNPD) to the m6A modified YAP1 mRNA, thus decreasing the stability of YAP1 mRNA. Furthermore, FAT1 increases YAP1 mRNA 3'UTR m6A modification by decreasing the activity of the TGFβ-Smad2/3 pathway and the subsequent expression of ALKBH5, which is regulated at the transcriptional level by Smad2/3. Collectively, these results reveal that FAT1 inhibits the proliferation of DLBCL cells by increasing the m6A modification of the YAP1 mRNA 3'UTR via the TGFβ-Smad2/3-ALKBH5 pathway. The findings of this study therefore indicate that FAT1 exerts anti-tumor effects in DLBCL and may represent a novel target in the treatment of this form of lymphoma.

Application and progress of CRISPR/Cas9 gene editing in B-cell lymphoma: a narrative review

Background and Objective

Clustered regularly interspaced short palindromic repeats (CRISPR)/CRISPR-associated 9 (Cas9) gene editing and CRISPR/Cas9 screening libraries are hot topics, and have high application values in the diagnosis and treatment of genetic diseases, and the improvement of prognosis. The major treatment of B-cell lymphoma is chemotherapy combined with biological therapy. Due to the individual specificity and the emergence of drug resistance, the therapeutic efficacy varies. The objective of this article is to explore potential targets to enhance therapeutic effects, optimize treatment plans, and improve the prognosis of patients with B-cell lymphoma.

Methods

We undertook a comprehensive, narrative review of the latest literature to define the current application and progress of CRISPR/Cas9 in B-cell lymphoma.

Key Content and Findings

The concepts of CRISPR/Cas9, the mechanism of gene editing, and the procedures of CRISPR/Cas9 screening libraries are investigated for candidate genes. We mainly focus on application and progress of CRISPR/Cas9 in B-cell lymphoma and screen out some genes, signaling pathways, and cytokines, which may become potential targets for clinical treatment.

Conclusions

CRISPR/Cas9 gene editing has great promise in the treatment of B-cell lymphoma. This article reviews some genes, signaling pathways, and cytokines related to the progression and prognosis of B-cell lymphoma to provide a strong theoretical basis.

NCAPD3 promotes diffuse large B-cell lymphoma progression through modulating SIRT1 expression in an H3K9 monomethylation-dependent manner

INTRODUCTION

Condensin, a family of structural maintenance of chromosome complexes, has been shown to regulate chromosome compaction and segregation during mitosis. NCAPD3, a HEAT-repeat subunit of condensin II, plays a dominant role in condensin-mediated chromosome dynamics but remains unexplored in lymphoma.

OBJECTIVES

The study aims to unravel the molecular function and mechanism of NCAPD3 in diffuse large B-cell lymphoma (DLBCL).

METHODS

The expression and clinical significance of NCAPD3 were assessed in public database and clinical specimens. Chromosome spreads, co-immunoprecipitation (co-IP), mass spectrometry (MS), and chromatin immunoprecipitation (ChIP) assays were conducted to untangle the role and mechanism of NCAPD3 in DLBCL.

RESULTS

NCAPD3 was highly expressed in DLBCL, correlated with poor prognosis. NCAPD3 deficiency impeded cell proliferation, induced apoptosis and increased the chemosensitivity. Instead, NCAPD3 overexpression facilitated cell proliferation. In vivo experiments further indicated targeting NCAPD3 suppressed tumor growth. Noteworthily, NCAPD3 deficiency disturbed the mitosis, triggering the formation of aneuploids. To reveal the function of NCAPD3 in DLBCL, chromosome spreads were conducted, presenting that chromosomes became compact upon NCAPD3 overexpression, instead, loose, twisted and lacking axial rigidity upon NCAPD3 absence. Meanwhile, the classical transcription-activated marker, H3K4 trimethylation, was found globally upregulated after NCAPD3 knockout, suggesting that NCAPD3 might participate in chromatin remodeling and transcription regulation. MS revealed NCAPD3 could interact with transcription factor, TFII I. Further co-IP and ChIP assays verified NCAPD3 could be anchored at the promoter of SIRT1 by TFII I and then supported the transcription of SIRT1 via recognizing H3K9 monomethylation (H3K9me1) on SIRT1 promoter. Function reversion assay verified the oncogenic role of NCAPD3 in DLBCL was partially mediated by SIRT1.

CONCLUSION

This study demonstrated that dysregulation of NCAPD3 could disturb chromosome compaction and segregation and regulate the transcription activity of SIRT1 in an H3K9me1-dependent manner, which provided novel insights into targeted strategy for DLBCL.

LATS1 Promotes B-ALL Tumorigenesis by Regulating YAP1 Phosphorylation and Subcellular Localization

OBJECTIVE

YAP1 plays a dual role as an oncogene and tumor suppressor gene in several tumors; differentiating between these roles may depend on the YAP1 phosphorylation pattern. The specific function of YAP1 in B cell acute lymphoblastic leukemia (B-ALL), however, is currently unclear. Thus, in the present study, the role of YAP1 in B-ALL was investigated using relevant cell lines and patient datasets.

METHODS

The effects of shRNA-mediated knockdown on YAP1 and LATS1 levels in the NALM6 and MOLT-4 cell lines were examined using Western blotting, quantitative real-time polymerase chain reaction, flow cytometry, immunostaining, and nude mouse subcutaneous tumorigenesis experiments. Gene expression levels of Hippo pathway-related molecules before and after verteporfin (VP) treatment were compared using RNA-Seq to identify significant Hippo pathway-related genes in NALM6 cells.

RESULTS

Patients with ALL showing high YAP1 expression and low YAP1-Ser127 phosphorylation levels had worse prognoses than those with low YAP1 protein expression and high YAP1-Ser127 phosphorylation levels. YAP1-Ser127 phosphorylation levels were lower in NALM6 cells than in MOLT-4 and control cells; YAP1 was distributed in the nuclei in NALM6 cells. Knockdown of YAP1 inhibited MOLT-4 and NALM6 cell proliferation and arrested the NALM6 cell cycle in the G0/G1 phase. Before and after VP treatment, the expression of the upstream gene LATS1 was upregulated; its overexpression promoted YAP1-Ser127 phosphorylation. Further, YAP1 was distributed in the plasma.

CONCLUSION

LATS1 may downregulate YAP1-Ser127 phosphorylation and maintain B-ALL cell function; thus, VP, which targets this axis, may serve as a new therapeutic method for improving the outcomes for B-ALL patients.

Ultra-Deep Sequencing Reveals the Mutational Landscape of Classical Hodgkin Lymphoma

The malignant Hodgkin and Reed Sternberg (HRS) cells of classical Hodgkin lymphoma (cHL) are scarce in affected lymph nodes, creating a challenge to detect driver somatic mutations. As an alternative to cell purification techniques, we hypothesized that ultra-deep exome sequencing would allow genomic study of HRS cells, thereby streamlining analysis and avoiding technical pitfalls. To test this, 31 cHL tumor/normal pairs were exome sequenced to approximately 1,000× median depth of coverage. An orthogonal error-corrected sequencing approach verified >95% of the discovered mutations. We identified mutations in genes novel to cHL including: CDH5 and PCDH7, novel stop gain mutations in IL4R, and a novel pattern of recurrent mutations in pathways regulating Hippo signaling. As a further application of our exome sequencing, we attempted to identify expressed somatic single-nucleotide variants (SNV) in single-nuclei RNA sequencing (snRNA-seq) data generated from a patient in our cohort. Our snRNA analysis identified a clear cluster of cells containing a somatic SNV identified in our deep exome data. This cluster has differentially expressed genes that are consistent with genes known to be dysregulated in HRS cells (e.g., PIM1 and PIM3). The cluster also contains cells with an expanded B-cell clonotype further supporting a malignant phenotype. This study provides proof-of-principle that ultra-deep exome sequencing can be utilized to identify recurrent mutations in HRS cells and demonstrates the feasibility of snRNA-seq in the context of cHL. These studies provide the foundation for the further analysis of genomic variants in large cohorts of patients with cHL.

SIGNIFICANCE

Our data demonstrate the utility of ultra-deep exome sequencing in uncovering somatic variants in Hodgkin lymphoma, creating new opportunities to define the genes that are recurrently mutated in this disease. We also show for the first time the successful application of snRNA-seq in Hodgkin lymphoma and describe the expression profile of a putative cluster of HRS cells in a single patient.

Identification of pyroptosis-related signature and development of a novel prognostic model in diffuse large B-cell lymphoma

PURPOSE

Emerging evidence suggests that pyroptosis plays an essential role in the development and progression of multiple cancers. However, the role of pyroptosis remains elusive in diffuse large B-cell lymphoma (DLBCL).

METHODS

The expression profile data of DLBCL and normal samples of pyroptosis-related genes (PRGs) were analyzed, and the clinical characteristics of DLBCL patients were further investigated. A prognostic model was established using LASSO-Cox regression analysis. The expression of these PRGs was validated by qRT-PCR in DLBCL cell lines. Cell proliferation assay and flow cytometry were utilized to explore the impact of pyroptosis inhibitor (disulfiram, DSF) combined with PD1/PD-L1 inhibitor (BMS1166) on DLBCL cell proliferation.

RESULTS

Most PRGs were dysregulated in DLBCL samples and associated with overall survival (OS). Six PRGs were selected to construct a prognostic risk score model. The qRT-PCR analysis revealed that CASP8, CASP9, NLRP1, NLRP6, and TIRAP are downregulated, while SCAF11 was significantly upregulated in DLBCL cell lines. This prognostic model divided DLBCL patients into low-risk and high-risk groups. Patients in the low-risk group exhibited lower mortality and longer OS than those in the high-risk group. The ROC curve and nomogram demonstrated this model's excellent predictive performance. GO and KEGG enrichment indicated that the differentially expressed genes (DEGs) between subgroups were associated with cellular protein modification processes and JAK-STAT signaling pathway regulation. Moreover, the risk score was correlated with the immune profile. Cell proliferation assay and flow cytometry further validated the synergistic anti-tumor effects of DSF and BMS1166 on DLBCL cells.

CONCLUSION

In summary, we developed a comprehensive prognostic model based on PRGs characteristics, which accurately predicted the prognosis of DLBCL patients. Pyroptosis-targeting coupled with immunotherapies would be a promising therapeutic strategy for DLBCL.

Targeting YTHDF2 inhibits tumorigenesis of diffuse large B-cell lymphoma through ACER2-mediated ceramide catabolism

INTRODUCTION

Epigenetic alterations play crucial roles in diffuse large B-cell lymphoma (DLBCL). Disturbances in lipid metabolism contribute to tumor progression. However, studies in epigenetics, especially its critical regulator YTH N6-methyladenosine RNA binding protein 2 (YTHDF2), on lipid metabolism regulation in DLBCL are unidentified.

OBJECTIVES

Elucidate the prognostic value and biological functions of YTHDF2 in DLBCL and illuminate the underlying epigenetic regulation mechanism of lipid metabolism by YTHDF2 in DLBCL development.

METHODS

The expression and clinical value of YTHDF2 in DLBCL were performed in public databases and clinical specimens. The biological functions of YTHDF2 in DLBCL were determined in vivo and in vitro through overexpression and CRISPR/Cas9-mediated knockout of YTHDF2. RNA sequencing, lipidomics, methylated RNA immunoprecipitation sequencing, RNA immunoprecipitation-qPCR, luciferase activity assay, and RNA stability experiments were used to explore the potential mechanism by which YTHDF2 contributed to DLBCL progression.

RESULTS

YTHDF2 was highly expressed in DLBCL, and related to poor prognosis. YTHDF2 overexpression exerted a tumor-promoting effect in DLBCL, and knockdown of YTHDF2 restricted DLBCL cell proliferation, arrested cell cycle in the G2/M phase, facilitated apoptosis, and enhanced drug sensitivity to ibrutinib and venetoclax. In addition, YTHDF2 knockout drastically suppressed tumor growth in xenograft DLBCL models. Furthermore, a regulatory role of YTHDF2 in ceramide metabolism was identified in DLBCL cells. Exogenous ceramide effectively inhibited the malignant phenotype of DLBCL cells in vitro. The binding of YTHDF2 to m6A sites on alkaline ceramidase 2 (ACER2) mRNA promoted its stability and expression. Enhanced ACER2 expression hydrolyzed ceramides, disrupting the balance between ceramide and sphingosine-1-phosphate (S1P), activating the ERK and PI3K/AKT pathways, and leading to DLBCL tumorigenesis.

CONCLUSION

This study demonstrated that YTHDF2 contributed to the progression of DLBCL by regulating ACER2-mediated ceramide metabolism in an m6A-dependent manner, providing novel insights into targeted therapies.

Histone regulator KAT2A acts as a potential biomarker related to tumor microenvironment and prognosis of diffuse large B cell lymphoma

BACKGROUND

Recent studies have indicated that epigenetic alterations contribute significantly to lymphoma pathogenesis. A type of epigenetic regulation known as histone acetylation plays a crucial role in transcriptional regulation in eukaryotic cells. Specifically, a significant effect of histone acetylation modifications on the abnormal progression and microenvironment of diffuse large B-cell lymphoma (DLBCL) has been observed.

METHODS

To provide insight into the significance of histone acetylation-related genes, we developed a HAscore model for analyzing histone acetylation patterns in DLBCL samples. Furthermore, KAT2A, a regulator of histone acetylation, was knocked down in DLBCL cell lines to investigate its role in proliferation, cell cycle, and apoptosis.

RESULTS

The HAscore model has been demonstrated to provide insight into the significance of these patterns, showing that patients with a low HAscore have distinct tumor immune microenvironments and poorer prognoses. Besides, KAT2A was identified as a potential biomarker related to immune infiltration and malignant pathways in DLBCL.

CONCLUSION

According to these findings, it is evident that the histone acetylation pattern score model is helpful in describing the immune status of DLBCL and that KAT2A may be used as a biomarker for its treatment.

Targeting HSP90 with picropodophyllin suppresses gastric cancer tumorigenesis by disrupting the association of HSP90 and AKT

Gastric cancer (GC) is one of the most common malignant tumors worldwide. Thus, the development of safe and effective therapeutic compounds for GC treatment is urgently required. Here, we aimed to examine the role of picropodophyllin (PPP), a compound extracted from the rhizome of Dysosma versipellis (Hance) M. Cheng ex Ying, on the proliferation of GC cells. Our study revealed that PPP inhibits the proliferation of GC cells in a dose-dependent manner by inducing apoptosis. Moreover, our study elucidated that PPP suppresses the growth of GC tumor xenografts with no side effects of observable toxicity. Mechanistically, PPP exerts its effects by blocking the AKT/mammalian target of rapamycin (mTOR) signaling pathway; these effects are markedly abrogated by the overexpression of constitutively active AKT. Furthermore, drug affinity responsive target stability (DARTS) and liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) revealed that heat shock protein 90 (HSP90) may be a potential target of PPP. Surface plasmon resonance and immunoprecipitation assay validated that PPP directly targets HSP90 and disrupts the binding of HSP90 to AKT, thereby suppressing GC cell proliferation. Thus, our study revealed that PPP may be a promising therapeutic compound for GC treatment.

Ferroptosis-related STEAP3 acts as predictor and regulator in diffuse large B cell lymphoma through immune infiltration

Diffuse large B cell lymphoma (DLBCL) is a usual-seen hematological malignant tumor possessing molecular and genetic heterogeneity. Ferroptosis induction has been increasingly acknowledged to be an advantageous therapeutic method in tumor treatment by triggering cell death of tumor cells. However, studies on the function of ferroptosis in DLBCL remain scarce, especially the interaction with the tumor immune microenvironment (TIME). The clinical and biological functions of ferroptosis-related genes in DLBCL were still warranted to be explored. A ferroptosis-related risk model was constructed, followed by functional enrichment analyses and evaluation of immune profile. Quantitative real-time PCR, western blotting, and immunohistochemistry were conducted to examine the RNA and protein levels. Dysregulated expression of the major ferroptosis-related genes was found in DLBCL. A prognostic risk model based on 10 ferroptosis-related genes was constructed. The risk score served as an independent prognostic indicator for DLBCL patients in univariate and multivariate Cox regression analysis. Patients with low-risk scores presented a more favorable prognosis. Functional enrichment analysis revealed that immune-related pathways were significantly enriched, and the high-risk group exhibited less immunocyte infiltration, lower immunoscore, and downregulated PD-L1 expression relative to the low-risk group. Two molecular subtypes were determined through consensus clustering of the expression of ferroptosis-related genes. Cluster 1 was relevant to favorable prognosis, higher immunoscore, and elevated PD-L1 expression. More importantly, STEAP3 was screened as a reliable biomarker for DLBCL, and its enhanced expression levels of mRNA and protein were verified in public databases and clinical specimens. Our study demonstrated the crucial role of ferroptosis-related genes including STEAP3 in the TIME of DLBCL and identified promising novel molecular targets for DLBCL treatment.

Targeting Hippo signaling in cancer: novel perspectives and therapeutic potential

As highly conserved among diverse species, Hippo signaling pathway regulates various biological processes, including development, cell proliferation, stem cell function, tissue regeneration, homeostasis, and organ size. Studies in the last two decades have provided a good framework for how these fundamental functions of Hippo signaling are tightly regulated by a network with numerous intracellular and extracellular factors. The Hippo signaling pathway, when dysregulated, may lead to a wide variety of diseases, especially cancer. There is growing evidence demonstrating that dysregulated Hippo signaling is closely associated with tumorigenesis, cancer cell invasion, and migration, as well as drug resistance. Therefore, the Hippo pathway is considered an appealing therapeutic target for the treatment of cancer. Promising novel agents targeting the Hippo signaling pathway for cancers have recently emerged. These novel agents have shown antitumor activity in multiple cancer models and demonstrated therapeutic potential for cancer treatment. However, the detailed molecular basis of the Hippo signaling-driven tumor biology remains undefined. Our review summarizes current advances in understanding the mechanisms by which Hippo signaling drives tumorigenesis and confers drug resistance. We also propose strategies for future preclinical and clinical development to target this pathway.

Activation of STING by SAMHD1 Deficiency Promotes PANoptosis and Enhances Efficacy of PD-L1 Blockade in Diffuse Large B-cell Lymphoma

Genomic instability is a significant driver of cancer. As the sensor of cytosolic DNA, the cyclic GMP-AMP synthase (cGAS)-stimulator of interferon genes (STING) pathway plays a critical role in regulating anti-tumor immunity and cell death. However, the role and regulatory mechanisms of STING in diffuse large B-cell lymphoma (DLBCL) are still undefined. In this study, we reported that sterile alpha motif and HD domain-containing protein 1 (SAMHD1) deficiency induced STING expression and inhibited tumor growth in DLBCL. High level of SAMHD1 was associated with poor prognosis in DLBCL patients. Down-regulation of SAMHD1 inhibited DLBCL cell proliferation both in vitro and in vivo. Moreover, we found that SAMHD1 deficiency induced DNA damage and promoted the expression of DNA damage adaptor STING. STING overexpression promoted the formation of Caspase 8/RIPK3/ASC, further leading to MLKL phosphorylation, Caspase 3 cleavage, and GSDME cleavage. Up-regulation of necroptotic, apoptotic, and pyroptotic effectors indicated STING-mediated PANoptosis. Finally, we demonstrated that the STING agonist, DMXAA, enhanced the efficacy of a PD-L1 inhibitor in DLBCL. Our findings highlight the important role of STING-mediated PANoptosis in restricting DLBCL progression and provide a potential strategy for enhancing the efficacy of immune checkpoint inhibitor agents in DLBCL.

Extracellular vesicle-circEHD2 promotes the progression of renal cell carcinoma by activating cancer-associated fibroblasts

BACKGROUND

The encapsulation of circular RNAs (circRNAs) into extracellular vesicles (EVs) enables their involvement in intercellular communication and exerts an influence on the malignant advancement of various tumors. However, the regulatory role of EVs-circRNA in renal cell carcinoma (RCC) remains elusive.

METHODS

The in vitro and in vivo functional experiments were implemented to measure the effects of circEHD2 on the phenotype of RCC. The functional role of EVs-circEHD2 on the activation of fibroblasts was assessed by collagen contraction assay, western blotting, and enzyme-linked immunosorbent assay (ELISA). The mechanism was investigated by RNA pull-down assay, RNA immunoprecipitation, chromatin isolation by RNA purification, luciferase assay, and co-immunoprecipitation assay.

RESULTS

We demonstrated that circEHD2 was upregulated in RCC tissues and serum EVs of RCC patients with metastasis. Silencing circEHD2 inhibited tumor growth in vitro and in vivo. Mechanistic studies indicated that FUS RNA -binding protein (FUS) accelerated the cyclization of circEHD2, then circEHD2 interacts with tyrosine 3-monooxygenase/tryptophan 5-monooxygenase activation protein eta (YWHAH), which acts as a bridge to recruit circEHD2 and Yes1-associated transcriptional regulator (YAP) to the promoter of SRY-box transcription factor 9 (SOX9); this results in the sustained activation of SOX9. Heterogeneous nuclear ribonucleoprotein A2/B1 (hnRNPA2B1) regulates the package of circEHD2 into EVs, then EVs-circEHD2 transmits to fibroblasts, converting fibroblasts to cancer-associated fibroblasts (CAFs). Activated CAFs promote the metastasis of RCC by secreting pro-inflammatory cytokines such as IL-6. Furthermore, antisense oligonucleotides (ASOs) targeting circEHD2 exhibited a strong inhibition of tumor growth in vivo.

CONCLUSIONS

The circEHD2/YWHAH/YAP/SOX9 signaling pathway accelerates the growth of RCC. EVs-circEHD2 facilitates the metastasis of RCC by converting fibroblasts to CAFs. Our results suggest that EVs-circEHD2 may be a useful biomarker and therapeutic target for RCC.

Reverse effect of Semaphorin-3F on rituximab resistance in diffuse large B-cell lymphoma via the Hippo pathway

BACKGROUND

Exploring the underlying mechanism of rituximab resistance is critical to improve the outcomes of patients with diffuse large B-cell lymphoma (DLBCL). Here, we tried to identify the effects of the axon guidance factor semaphorin-3F (SEMA3F) on rituximab resistance as well as its therapeutic value in DLBCL.

METHODS

The effects of SEMA3F on the treatment response to rituximab were investigated by gain- or loss-of-function experiments. The role of the Hippo pathway in SEMA3F-mediated activity was explored. A xenograft mouse model generated by SEMA3F knockdown in cells was used to evaluate rituximab sensitivity and combined therapeutic effects. The prognostic value of SEMA3F and TAZ (WW domain-containing transcription regulator protein 1) was examined in the Gene Expression Omnibus (GEO) database and human DLBCL specimens.

RESULTS

We found that loss of SEMA3F was related to a poor prognosis in patients who received rituximab-based immunochemotherapy instead of chemotherapy regimen. Knockdown of SEMA3F significantly repressed the expression of CD20 and reduced the proapoptotic activity and complement-dependent cytotoxicity (CDC) activity induced by rituximab. We further demonstrated that the Hippo pathway was involved in the SEMA3F-mediated regulation of CD20. Knockdown of SEMA3F expression induced the nuclear accumulation of TAZ and inhibited CD20 transcriptional levels via direct binding of the transcription factor TEAD2 and the CD20 promoter. Moreover, in patients with DLBCL, SEMA3F expression was negatively correlated with TAZ, and patients with SEMA3F low TAZ high had a limited benefit from a rituximab-based strategy. Specifically, treatment of DLBCL cells with rituximab and a YAP/TAZ inhibitor showed promising therapeutic effects in vitro and in vivo .

CONCLUSION

Our study thus defined a previously unknown mechanism of SEMA3F-mediated rituximab resistance through TAZ activation in DLBCL and identified potential therapeutic targets in patients.

The role of Hippo pathway in ovarian development

The follicle is the functional unit of the ovary, whereby ovarian development is largely dependent on the development of the follicles themselves. The activation, growth, and progression of follicles are modulated by a diverse range of factors, including reproductive endocrine system and multiple signaling pathways. The Hippo pathway exhibits a high degree of evolutionary conservation between both Drosophila and mammalian systems, and is recognized for its pivotal role in regulating cellular proliferation, control of organ size, and embryonic development. During the process of follicle development, the components of the Hippo pathway show temporal and spatial variations. Recent clinical studies have shown that ovarian fragmentation can activate follicles. The mechanism is that the mechanical signal of cutting triggers actin polymerization. This process leads to the disruption of the Hippo pathway and subsequently induces the upregulation of downstream CCN and apoptosis inhibitors, thereby promoting follicle development. Thus, the Hippo pathway plays a crucial role in both the activation and development of follicles. In this article, we focused on the development and atresia of follicles and the function of Hippo pathway in these processes. Additionally, the physiological effects of Hippo pathway in follicle activation are also explored.

Single-cell transcriptome analysis profiles the expression features of TMEM173 in BM cells of high-risk B-cell acute lymphoblastic leukemia

BACKGROUND

As an essential regulator of type I interferon (IFN) response, TMEM173 participates in immune regulation and cell death induction. In recent studies, activation of TMEM173 has been regarded as a promising strategy for cancer immunotherapy. However, transcriptomic features of TMEM173 in B-cell acute lymphoblastic leukemia (B-ALL) remain elusive.

METHODS

Quantitative real-time PCR (qRT-PCR) and western blotting (WB) were applied to determine the mRNA and protein levels of TMEM173 in peripheral blood mononuclear cells (PBMCs). TMEM173 mutation status was assessed by Sanger sequencing. Single-cell RNA sequencing (scRNA-seq) analysis was performed to explore the expression of TMEM173 in different types of bone marrow (BM) cells.

RESULTS

The mRNA and protein levels of TMEM173 were increased in PBMCs from B-ALL patients. Besides, frameshift mutation was presented in TMEM173 sequences of 2 B-ALL patients. ScRNA-seq analysis identified the specific transcriptome profiles of TMEM173 in the BM of high-risk B-ALL patients. Specifically, expression levels of TMEM173 in granulocytes, progenitor cells, mast cells, and plasmacytoid dendritic cells (pDCs) were higher than that in B cells, T cells, natural killer (NK) cells, and dendritic cells (DCs). Subset analysis further revealed that TMEM173 and pyroptosis effector gasdermin D (GSDMD) restrained in precursor-B (pre-B) cells with proliferative features, which expressed nuclear factor kappa-B (NF-κB), CD19, and Bruton's tyrosine kinase (BTK) during the progression of B-ALL. In addition, TMEM173 was associated with the functional activation of NK cells and DCs in B-ALL.

CONCLUSIONS

Our findings provide insights into the transcriptomic features of TMEM173 in the BM of high-risk B-ALL patients. Targeted activation of TMEM173 in specific cells might provide new therapeutic strategies for B-ALL patients.

The interplay between IGF-1R signaling and Hippo-YAP in breast cancer stem cells

BACKGROUND

Both IGF-1R/PI3K/AKT/mTOR and Hippo pathways are crucial for breast cancer stem cells (BCSCs). However, their interplay remains unclear.

METHODS

Four triple negative breast cancer cell lines derived from CSC of two patient-derived xenografts (PDXs), AS-B145, AS-B145-1R, AS-B244, and AS-B244-1R, were used to elucidate the role of YAP in BCSCs. YAP silenced BCSCs were analyzed by cell proliferation, aldehyde dehydrogenase (ALDH) activity, mammosphere formation, and tumorigenesis. The effects of modulating IGF-1R and IGF-1 on YAP expression and localization were evaluated. The clinical correlation of YAP and IGF-1R signaling with the overall survival (OS) of 7830 breast cancer patients was analyzed by KM plotter.

RESULTS

Knockdown of YAP abates the viability and stemness of BCSCs in vitro and tumorigenicity in vivo. Depletion of IGF-1R by shRNA or specific inhibitor decreases YAP expression. In contrast, IGF-1 addition upregulates YAP and enhances its nuclear localization. YAP overexpression increased the mRNA level of IGF-1, but not IGF-1R. Data mining of clinical breast cancer specimens revealed that basal-like breast cancer patients with higher level of IGF-1 and YAP exhibit significantly shorter OS.

CONCLUSIONS

YAP contributes to stemness features of breast cancer in vitro and in vivo. The expression and localization of YAP was regulated by IGF-1R and YAP expression in turns upregulates IGF-1, but not IGF-1R. Clinically, higher level of YAP and IGF-1 significantly correlated with shorter OS in basal-like breast cancer. Taken together, these findings suggest the clinical relevance of interplay between YAP and IGF-1/IGF-1R pathway in sustaining the properties of BCSCs. Video Abstract.

KIAA1429-mediated m6A modification of CHST11 promotes progression of diffuse large B-cell lymphoma by regulating Hippo-YAP pathway

BACKGROUND

N⁶-methyladenosine (m6A) has been shown to participate in various essential biological processes by regulating the level of target genes. However, the function of m6A modification mediated by KIAA1429 [alias virus-like m6A methyltransferase-associated protein (VIRMA)] during the progression of diffuse large B-cell lymphoma (DLBCL) remains undefined.

METHODS

The expression and clinical significance of KIAA1429 were verified by our clinical data. CRISPR/Cas9 mediated KIAA1429 deletion, and CRISPR/dCas9-VP64 for activating endogenous KIAA1429 was used to evaluate its biological function. RNA sequencing (RNA-seq), methylated RNA immunoprecipitation sequencing (MeRIP-seq), RNA immunoprecipitation (RIP) assays, luciferase activity assay, RNA stability experiments, and co-immunoprecipitation were performed to investigate the regulatory mechanism of KIAA1429 in DLBCL. Tumor xenograft models were established for in vivo experiments.

RESULTS

Dysregulated expression of m6A regulators was observed, and a novel predictive model based on m6A score was established in DLBCL. Additionally, elevated KIAA1429 expression was associated with poor prognosis of patients with DLBCL. Knockout of KIAA1429 repressed DLBCL cell proliferation, facilitated cell cycle arrest in the G2/M phase, induced apoptosis in vitro, and inhibited tumor growth in vivo. Furthermore, carbohydrate sulfotransferase 11 (CHST11) was identified as a downstream target of KIAA1429, which mediated m6A modification of CHST11 mRNA and then recruited YTHDF2 for reducing CHST11 stability and expression. Inhibition of CHST11 diminished MOB1B expression, resulting in inactivation of Hippo-YAP signaling, reprogramming the expression of Hippo target genes.

CONCLUSIONS

Our results revealed a new mechanism by which the Hippo-YAP pathway in DLBCL is inactivated by KIAA1429/YTHDF2-coupled epitranscriptional repression of CHST11, highlighting the potential of KIAA1429 as a novel predictive biomarker and therapeutic target for DLBCL progression.

Potential Pathogenic Impact of Cow’s Milk Consumption and Bovine Milk-Derived Exosomal MicroRNAs in Diffuse Large B-Cell Lymphoma

Epidemiological evidence supports an association between cow’s milk consumption and the risk of diffuse large B-cell lymphoma (DLBCL), the most common non-Hodgkin lymphoma worldwide. This narrative review intends to elucidate the potential impact of milk-related agents, predominantly milk-derived exosomes (MDEs) and their microRNAs (miRs) in lymphomagenesis. Upregulation of PI3K-AKT-mTORC1 signaling is a common feature of DLBCL. Increased expression of B cell lymphoma 6 (BCL6) and suppression of B lymphocyte-induced maturation protein 1 (BLIMP1)/PR domain-containing protein 1 (PRDM1) are crucial pathological deviations in DLBCL. Translational evidence indicates that during the breastfeeding period, human MDE miRs support B cell proliferation via epigenetic upregulation of BCL6 (via miR-148a-3p-mediated suppression of DNA methyltransferase 1 (DNMT1) and miR-155-5p/miR-29b-5p-mediated suppression of activation-induced cytidine deaminase (AICDA) and suppression of BLIMP1 (via MDE let-7-5p/miR-125b-5p-targeting of PRDM1). After weaning with the physiological termination of MDE miR signaling, the infant’s BCL6 expression and B cell proliferation declines, whereas BLIMP1-mediated B cell maturation for adequate own antibody production rises. Because human and bovine MDE miRs share identical nucleotide sequences, the consumption of pasteurized cow’s milk in adults with the continued transfer of bioactive bovine MDE miRs may de-differentiate B cells back to the neonatal “proliferation-dominated” B cell phenotype maintaining an increased BLC6/BLIMP1 ratio. Persistent milk-induced epigenetic dysregulation of BCL6 and BLIMP1 expression may thus represent a novel driving mechanism in B cell lymphomagenesis. Bovine MDEs and their miR cargo have to be considered potential pathogens that should be removed from the human food chain.

The circular RNA circHelz enhances cardiac fibrosis by facilitating the nuclear translocation of YAP1

Cardiac fibrosis is a common pathological change in the development of heart disease. Circular RNA (circRNA) has been shown to be related to the occurrence and development of various cardiovascular diseases. This study aimed to evaluate the effects and potential mechanisms of circHelz in cardiac fibrosis. Knockdown of circHelz alleviated cardiac fibrosis and myocardial fibroblast activation induced by myocardial infarction (MI) or angiotensin II (AngII) in vivo and transforming growth factor-β (TGF-β) in vitro. Overexpression of circHelz exacerbated cell proliferation and differentiation. Mechanistically, nuclear factor of activated T cells, cytoplasmic 2 (NFATc2) was found to act as a transcriptional activator to upregulate the expression of circHelz. The increased circHelz was demonstrated to bind to Yes-associated protein (YAP) and facilitate its localization in the nucleus to promote cell proliferation and growth. Moreover, silencing YAP1 reversed the detrimental effects caused by circHelz in vitro, as indicated by the observed decreases in cell viability, fibrotic marker expression levels, proliferation and migration. Collectively, the protective effect of circHelz knockdown against cardiac fibrosis injury is accomplished by inhibiting the nuclear translocation of YAP1. Thus, circHelz may be a novel target for the prevention and treatment of cardiovascular disease.

PGD2 displays distinct effects in diffuse large B-cell lymphoma depending on different concentrations

Prostaglandin D2 (PGD2), an arachidonic acid metabolite, has been implicated in allergic responses, parasitic infection and tumor development. The biological functions and molecular mechanisms of PGD2 in diffuse large B-cell lymphoma (DLBCL) are still undefined. In this study, we firstly found the high concentration of serum PGD2 and low expression of PGD2 receptor CRTH2 in DLBCL, which were associated with clinical features and prognosis of DLBCL patients. Interestingly, different concentration of PGD2 displayed divergent effects on DLBCL progression. Low-concentration PGD2 promoted cell growth through binding to CRTH2 while high-concentration PGD2 inhibited it via regulating cell proliferation, apoptosis, cell cycle, and invasion. Besides, high-concentration PGD2 could induce ROS-mediated DNA damage and enhance the cytotoxicity of adriamycin, bendamustine and venetoclax. Furthermore, HDAC inhibitors, vorinostat (SAHA) and panobinostat (LBH589) regulated CRTH2 expression and PGD2 production, and CRTH2 inhibitor AZD1981 and high-concentration PGD2 enhanced their anti-tumor effects in DLBCL. Altogether, our findings demonstrated PGD2 and CRTH2 as novel prognostic biomarkers and therapeutic targets in DLBCL, and highlighted the potency of high-concentration PGD2 as a promising therapeutic strategy for DLBCL patients.

Cancer-associated fibroblasts potentiate colorectal cancer progression by crosstalk of the IGF2-IGF1R and Hippo-YAP1 signaling pathways

Colorectal cancer (CRC) is one of the most common cancers worldwide. The tumor microenvironment exerts crucial effects in driving CRC progression. Cancer-associated fibroblasts (CAFs) serve as one of the most important tumor microenvironment components promoting CRC progression. This study aimed to elucidate the novel molecular mechanisms of CAF-secreted insulin-like growth factor (IGF) 2 in colorectal carcinogenesis. Our results indicated that IGF2 was a prominent factor upregulated in CAFs compared with normal fibroblasts. CAF-derived conditioned media (CM) promoted tumor growth, migration, and invasion of HCT 116 and DLD-1 cells. IGF1R expression is significantly increased in CRC, serving as a potent receptor in response to IGF2 stimulation and predicting unfavorable outcomes for CRC patients. Apart from the PI3K-AKT pathway, RNA-seq analysis revealed that the YAP1-target signature serves as a prominent downstream effector to mediate the oncogenic signaling of IGF2-IGF1R. By single-cell RNA sequencing (scRNA-seq) and immunohistochemical validation, IGF2 was found to be predominantly secreted by CAFs, whereas IGF1R was expressed mainly by cancer cells. IGF2 triggers the nuclear accumulation of YAP1 and upregulates YAP1 target signatures; however, these effects were abolished by either IGF1R knockdown or inhibition with picropodophyllin (PPP), an IGF1R inhibitor. Using CRC organoid and in vivo studies, we found that cotargeting IGF1R and YAP1 with PPP and verteporfin (VP), a YAP1 inhibitor, enhanced antitumor effects compared with PPP treatment alone. In conclusion, this study revealed a novel molecular mechanism by which CAFs promote CRC progression. The findings highlight the translational potential of the IGF2-IGF1R-YAP1 axis as a prognostic biomarker and therapeutic target for CRC. © 2022 The Pathological Society of Great Britain and Ireland.

The Hippo signalling pathway and its implications in human health and diseases

As an evolutionarily conserved signalling network, the Hippo pathway plays a crucial role in the regulation of numerous biological processes. Thus, substantial efforts have been made to understand the upstream signals that influence the activity of the Hippo pathway, as well as its physiological functions, such as cell proliferation and differentiation, organ growth, embryogenesis, and tissue regeneration/wound healing. However, dysregulation of the Hippo pathway can cause a variety of diseases, including cancer, eye diseases, cardiac diseases, pulmonary diseases, renal diseases, hepatic diseases, and immune dysfunction. Therefore, therapeutic strategies that target dysregulated Hippo components might be promising approaches for the treatment of a wide spectrum of diseases. Here, we review the key components and upstream signals of the Hippo pathway, as well as the critical physiological functions controlled by the Hippo pathway. Additionally, diseases associated with alterations in the Hippo pathway and potential therapies targeting Hippo components will be discussed.

Metabolic Reprogramming in Hematologic Malignancies: Advances and Clinical Perspectives

Metabolic reprogramming is a hallmark of cancer progression. Metabolic activity supports tumorigenesis and tumor progression, allowing cells to uptake essential nutrients from the environment and use the nutrients to maintain viability and support proliferation. The metabolic pathways of malignant cells are altered to accommodate increased demand for energy, reducing equivalents, and biosynthetic precursors. Activated oncogenes coordinate with altered metabolism to control cell-autonomous pathways, which can lead to tumorigenesis when abnormalities accumulate. Clinical and preclinical studies have shown that targeting metabolic features of hematologic malignancies is an appealing therapeutic approach. This review provides a comprehensive overview of the mechanisms of metabolic reprogramming in hematologic malignancies and potential therapeutic strategies to target cancer metabolism.

IGF-1R/YAP signaling pathway is involved in collagen V-induced insulin biosynthesis and secretion in rat islet INS-1 cells

PURPOSE

Type V collagen (collagen V) is one of the important components of extracellular matrix (ECM) in pancreas. We previously reported that pre-coating collagen V on the culture dishes enhanced insulin production in INS-1 rat pancreatic β cells. In this study, we investigate the underlying mechanism.

RESULTS

Insulin biosynthesis and secretion are both increased in INS-1 cells cultured on collagen V-coated dishes, accompanied by the reduced nuclear translocation of Yes-associated protein (YAP), a transcriptional co-activator. YAP, the downstream effector of Hippo signaling pathway, plays an important role in the development and function of pancreas. Inhibition of YAP activation by verteporfin further up-regulates insulin biosynthesis and secretion. Silencing large tumor suppressor (LATS), a core component of Hippo pathway which inhibits activity of YAP by phosphorylation, by siRNA transfection inhibits both insulin biosynthesis and secretion. In the present study, the protein level of insulin-like growth factor 1 receptor (IGF-1 R), detected as the upstream molecule of YAP, is reduced in the INS-1 cells cultured on the dishes coated with collagen V. The silencing of IGF-1 R by siRNA transfection further enhances insulin biosynthesis and secretion. IGF-1 treatment reduces collagen V-induced up-regulation of insulin biosynthesis and secretion, accompanying the increased nuclear YAP.

CONCLUSION

Inhibition of IGF-1 R/YAP signal pathway is involved in collagen V-induced insulin biosynthesis and secretion in INS-1 cells.

Genome editing and cancer: How far has research moved forward on CRISPR/Cas9?

Cancer accounted for almost ten million deaths worldwide in 2020. Metastasis, characterized by cancer cell invasion to other parts of the body, is the main cause of cancer morbidity and mortality. Therefore, understanding the molecular mechanisms of tumor formation and discovery of potential drug targets are of great importance. Gene editing techniques can be used to find novel drug targets and study molecular mechanisms. In this review, we describe how popular gene-editing methods such as CRISPR/Cas9, TALEN and ZFNs work, and, by comparing them, we demonstrate that CRISPR/Cas9 has superior efficiency and precision. We further provide an overview of the recent applications of CRISPR/Cas9 to cancer research, focusing on the most common cancers such as breast cancer, lung cancer, colorectal cancer, and prostate cancer. We describe how these applications will shape future research and treatment of cancer, and propose new ways to overcome current challenges.

Fusion protein-driven IGF-IR/PI3K/AKT signals deregulate Hippo pathway promoting oncogenic cooperation of YAP1 and FUS-DDIT3 in myxoid liposarcoma

Myxoid liposarcoma (MLS) represents a common subtype of liposarcoma molecularly characterized by a recurrent chromosomal translocation that generates a chimeric FUS-DDIT3 fusion gene. The FUS-DDIT3 oncoprotein has been shown to be crucial in MLS pathogenesis. Acting as a transcriptional dysregulator, FUS-DDIT3 stimulates proliferation and interferes with adipogenic differentiation. As the fusion protein represents a therapeutically challenging target, a profound understanding of MLS biology is elementary to uncover FUS-DDIT3-dependent molecular vulnerabilities. Recently, a specific reliance on the Hippo pathway effector and transcriptional co-regulator YAP1 was detected in MLS; however, details on the molecular mechanism of FUS-DDIT3-dependent YAP1 activation, and YAP1´s precise mode of action remain unclear. In elaborate in vitro studies, employing RNA interference-based approaches, small-molecule inhibitors, and stimulation experiments with IGF-II, we show that FUS-DDIT3-driven IGF-IR/PI3K/AKT signaling promotes stability and nuclear accumulation of YAP1 via deregulation of the Hippo pathway. Co-immunoprecipitation and proximity ligation assays revealed nuclear co-localization of FUS-DDIT3 and YAP1/TEAD in FUS-DDIT3-expressing mesenchymal stem cells and MLS cell lines. Transcriptome sequencing of MLS cells demonstrated that FUS-DDIT3 and YAP1 co-regulate oncogenic gene signatures related to proliferation, cell cycle progression, apoptosis, and adipogenesis. In adipogenic differentiation assays, we show that YAP1 critically contributes to FUS-DDIT3-mediated adipogenic differentiation arrest. Taken together, our study provides mechanistic insights into a complex FUS-DDIT3-driven network involving IGF-IR/PI3K/AKT signals acting on Hippo/YAP1, and uncovers substantial cooperative effects of YAP1 and FUS-DDIT3 in the pathogenesis of MLS.

m6A binding protein YTHDF2 in cancer

YT521-B homology domain family member 2 (YTHDF2) is an N⁶-methyladenosine (m⁶A)-binding protein that was originally found to regulate the stability of mRNA. Growing evidence has shown that YTHDF2 can participate in multifarious bioprocesses, including embryonic development, immune response, and tumor progression. Furthermore, YTHDF2 is closely associated with the proliferation, apoptosis, invasion, and migration of tumor cells, suggesting its significant role in cancers. YTHDF2 primarily relies on m⁶A modification to modulate signaling pathways in cancer cells. However, the expression and function of YTHDF2 in human malignancies remain controversial. Meanwhile, the underlying molecular mechanisms of YTHDF2 have not been elucidated. In this review, we principally summarized the biological functions and molecular mechanisms of YTHDF2 in tumors and discussed its prognostic and therapeutic values.

Targeting extracellular matrix stiffness and mechanotransducers to improve cancer therapy

Cancer microenvironment is critical for tumorigenesis and cancer progression. The extracellular matrix (ECM) interacts with tumor and stromal cells to promote cancer cells proliferation, migration, invasion, angiogenesis and immune evasion. Both ECM itself and ECM stiffening-induced mechanical stimuli may activate cell membrane receptors and mechanosensors such as integrin, Piezo1 and TRPV4, thereby modulating the malignant phenotype of tumor and stromal cells. A better understanding of how ECM stiffness regulates tumor progression will contribute to the development of new therapeutics. The rapidly expanding evidence in this research area suggests that the regulators and effectors of ECM stiffness represent potential therapeutic targets for cancer. This review summarizes recent work on the regulation of ECM stiffness in cancer, the effects of ECM stiffness on tumor progression, cancer immunity and drug resistance. We also discuss the potential targets that may be druggable to intervene ECM stiffness and tumor progression. Based on these advances, future efforts can be made to develop more effective and safe drugs to interrupt ECM stiffness-induced oncogenic signaling, cancer progression and drug resistance.

Glycoprotein PTGDS promotes tumorigenesis of diffuse large B-cell lymphoma by MYH9-mediated regulation of Wnt-β-catenin-STAT3 signaling

Glycoprotein prostaglandin D2 synthase (PTGDS) is a member of the lipocalin superfamily and plays dual roles in prostaglandins metabolism and lipid transport. PTGDS has been involved in various cellular processes including the tumorigenesis of solid tumors, yet its role in carcinogenesis is contradictory and the significance of PTGDS in hematological malignancies is ill-defined. Here, we aimed to explore the expression and function of PTGDS in diffuse large B-cell lymphoma (DLBCL), especially the potential role of PTGDS inhibitor, AT56, in lymphoma therapy. Remarkable high expression of PTGDS was found in DLBCL, which was significantly correlated with poor prognosis. PTGDS overexpression and rhPTGDS were found to promote cell proliferation. Besides, in vitro and in vivo studies indicated that PTGDS knockdown and AT56 treatment exerted an anti-tumor effect by regulating cell viability, proliferation, apoptosis, cell cycle, and invasion, and enhanced the drug sensitivity to adriamycin and bendamustine through promoting DNA damage. Moreover, the co-immunoprecipitation-based mass spectrum identified the interaction between PTGDS and MYH9, which was found to promote DLBCL progression. PTGDS inhibition led to reduced expression of MYH9, and then declined activation of the Wnt-β-catenin-STAT3 pathway through influencing the ubiquitination and degradation of GSK3-β in DLBCL. The rescue experiment demonstrated that PTGDS exerted an oncogenic role through regulating MYH9 and then the Wnt-β-catenin-STAT3 pathway. Based on point mutation of glycosylation sites, we confirmed the N-glycosylation of PTGDS in Asn51 and Asn78 and found that abnormal glycosylation of PTGDS resulted in its nuclear translocation, prolonged half-life, and enhanced cell proliferation. Collectively, our findings identified for the first time that glycoprotein PTGDS promoted tumorigenesis of DLBCL through MYH9-mediated regulation of Wnt-β-catenin-STAT3 signaling, and highlighted the potential role of AT56 as a novel therapeutic strategy for DLBCL treatment.

Prognostic Value of Sarcopenia in Patients With Diffuse Large B-Cell Lymphoma Treated With R-CHOP: A Systematic Review and Meta-Analysis

Objective

Several studies have reported conflicting results regarding the association between sarcopenia and outcomes in patients with diffuse large B-cell lymphoma (DLBCL). This meta-analysis aimed to evaluate the prognostic value of sarcopenia in patients with DLBCL.

Methods

PubMed, Embase, and Cochrane Library databases were searched to identify trials exploring the association between sarcopenia and prognosis in patients with DLBCL treated with chemotherapy. A meta-analysis of overall survival (OS), progression-free survival (PFS), treatment completion, and rate of complete response (CR) was performed.

Results

Twelve studies that involved 2,324 patients with DLBCL were included. Sarcopenia was associated with poor OS and PFS in patients with DLBCL, even after adjusting for confounders. Patients with sarcopenia had lower rates of CR and treatment completion than patients without sarcopenia.

Conclusions

Sarcopenia is a negative predictor of prognosis in patients with DLBCL. Additional and prospective studies investigating the diagnostic criteria for sarcopenia are warranted.

The ovarian reserve as target of insulin/IGF and ROS in metabolic disorder-dependent ovarian dysfunctions

It is known for a long time that metabolic disorders can cause ovarian dysfunctions and affect a woman’s fertility either by direct targeting follicular cells and/or the oocytes or by indirect interference with the pituitary-hypothalamic axis, resulting in dysfunctional oogenesis. Such disorders may also influence the efficiency of the embryo implantation and the quality of the embryo with permanent effects on the fertility and health of the offspring. Thanks to the expanding knowledge on the molecular mechanisms governing oogenesis and folliculogenesis in mammals, we are beginning to understand how such disorders can negatively affect this process and consequently fertility in women. In the present review, we point out and discuss how the disturbance of insulin/IGF-dependent signalling and increased reactive oxygen species (ROS) level in the ovary typically associated to metabolic disorders such as type II diabetes and obesity can dysregulate the dynamics of the ovarian reserve and/or impair the survival and competence of the oocytes.

Nucleolar and spindle associated protein 1 enhances chemoresistance through DNA damage repair pathway in chronic lymphocytic leukemia by binding with RAD51

Nucleolar and spindle-associated protein 1 (NUSAP1) is an essential regulator of mitotic progression, spindle assembly, and chromosome attachment. Although NUSAP1 acts as an oncogene involved in the progression of several cancers, the exact role of chronic lymphocytic leukemia (CLL) remains elusive. Herein, we first discovered obvious overexpression of NUSAP1 in CLL associated with poor prognosis. Next, the NUSAP1 level was modulated by transfecting CLL cells with lentivirus. Silencing NUSAP1 inhibited the cell proliferation, promoted cell apoptosis and G0/G1 phase arrest. Mechanistically, high expression of NUSAP1 strengthened DNA damage repairing with RAD51 engagement. Our results also indicated that NUSAP1 knockdown suppressed the growth CLL cells in vivo. We further confirmed that NUSAP1 reduction enhanced the sensitivity of CLL cells to fludarabine or ibrutinib. Overall, our research investigates the mechanism by which NUSAP1 enhances chemoresistance via DNA damage repair (DDR) signaling by stabilizing RAD51 in CLL cells. Hence, NUSAP1 may be expected to be a perspective target for the treatment of CLL with chemotherapy resistance.

Periodontal ligament fibroblast-derived exosomes induced by compressive force promote macrophage M1 polarization via Yes-associated protein

OBJECTIVES

This study aimed to investigate the biological roles and mechanisms of compressive force-stimulated periodontal ligament fibroblasts (PDLFs) on polarization of macrophages DESIGN: PDLFs were stimulated with or without static compressive force, and then conditioned medium, high-molecular weight proteins and low-molecular weight proteins were collected to treat THP-1 macrophages. RT-qPCR and flow cytometric analysis were used to evaluate the polarization of macrophages. Exosomes were isolated by ultracentrifugation method and identified via transmission electron microscopy, western-blot and nano-tracking analysis. The protein level of Yes-Associated Protein (YAP) contained in exosomes was detected by western blot. GW4869 and Verteporfin were used to inhibit exosome secretion and YAP- TEA domain transcription factor (TEAD) interaction respectively.

RESULTS

Exosomes were successfully purified from PDLFs and could be efficiently incorporated into THP-1 macrophages. conditioned medium, HMW proteins and exosomes derived from compressive force-treated PDLFs significantly induce M1 polarization of macrophages. While inhibiting exosomes secretion by GW4869 treatment eliminated the inductive effect. YAP target genes, connective tissue growth factor (CTGF) and cysteine-rich angiogenic inducer 61 (CYR61) were upregulated in macrophages when treated with exosomes derived from compressive force-treated PDLFs (F-Exo). YAP level was elevated in the F-Exo. When macrophages were treated with Verteporfin, expression of YAP target genes and M1 polarization were significantly downregulated.

CONCLUSION

These results suggested that exosomes derived from compressive force-treated PDLFs promoted the M1 polarization of the THP-1 macrophages. The elevated level of YAP in the exosomes may be a critical factor for this response.

IGF2BP2 promotes the progression of colorectal cancer through a YAP-dependent mechanism

To explore the effect of insulin-like growth factor 2 mRNA-binding protein 2 (IGF2BP2) on colorectal cancer (CRC) by recognizing the m6A modification of YAP mRNA thus activating ErbB2 expression. High expressions of IGF2BP2, YAP, and ErbB2 promoted the proliferation, migration and invasion of CRC cells and reduced their apoptosis. IGF2BP2 recognized the m6A on YAP mRNA and promoted the translation of mRNA. YAP regulated ErbB2 expression by promoting TEAD4 enrichment in ErbB2 promoter region. Therefore, IGF2BP2 promoted the expression of ErbB2 to enhance the proliferation, invasion and migration of CRC cells, to repress cell apoptosis, and to promote solid tumor formation in nude mice. IGF2BP2 activates the expression of ErbB2 by recognizing the m6A of YAP, thus affecting the cell cycle of CRC, inhibiting cell apoptosis, and promoting proliferation.

Unraveling the IGF System Interactome in Sarcomas Exploits Novel Therapeutic Options

Aberrant bioactivity of the insulin-like growth factor (IGF) system results in the development and progression of several pathologic conditions including cancer. Preclinical studies have shown promising anti-cancer therapeutic potentials for anti-IGF targeted therapies. However, a clear but limited clinical benefit was observed only in a minority of patients with sarcomas. The molecular complexity of the IGF system, which comprises multiple regulators and interactions with other cancer-related pathways, poses a major limitation in the use of anti-IGF agents and supports the need of combinatorial therapeutic strategies to better tackle this axis. In this review, we will initially highlight multiple mechanisms underlying IGF dysregulation in cancer and then focus on the impact of the IGF system and its complexity in sarcoma development and progression as well as response to anti-IGF therapies. We will also discuss the role of Ephrin receptors, Hippo pathway, BET proteins and CXCR4 signaling, as mediators of sarcoma malignancy and relevant interactors with the IGF system in tumor cells. A deeper understanding of these molecular interactions might provide the rationale for novel and more effective therapeutic combinations to treat sarcomas.

GPNMB promotes the progression of diffuse large B cell lymphoma via YAP1-mediated activation of the Wnt/β-catenin signaling pathway

Glycoprotein non-metastatic melanoma protein B (GPNMB) has been confirmed to be related to the pathogenesis of tumors. However, the potential impact of GPNMB on the progression of diffuse large B-cell lymphoma (DLBCL) is unclear. In this study, the expression levels of GPNMB and Yes-associated protein (YAP) were analyzed using qRT-PCT and Western blot assay. Cell counting kit-8, EdU, and flow cytometry assays were used to detect the proliferation and apoptosis of DLBCL cells. A nude mice xenograft model was established for in vivo research. Results showed that GPNMB and YAP1 were upregulated in DLBCL cell lines. Knockdown of GPNMB inhibited cell proliferation and promoted apoptosis in DLBCL cells. Additionally, the expression levels of YAP1 and the downstream effector of Hippo pathway (c-myc) were markedly decreased when GPNMB was knocked down. Moreover, knockdown of GPNMB inhibited the nuclear translocation of β-catenin protein, which could be abolished by YAP1 overexpression. Simultaneously, the anti-proliferative and pro-apoptotic effects of GPNMB knockdown could be reversed by YAP1 overexpression or LiCl (the activator of Wnt/β-catenin pathway). Furthermore, the mice xenograft model confirmed that inhibition of GPNMB restrained the tumorigenesis of DLBCL in vivo. In conclusion, GPNMB could partly activate the Wnt/β-catenin signaling pathway by targeting YAP1, so as to participate in tumorigenesis of DLBCL.

Derivation and validation of a lipid-covered prognostic model for mature T-cell lymphomas

Background

Mature T-cell lymphomas (MTCLs), a group of diseases with high aggressiveness and vulnerable prognosis, lack for the accurate prognostic stratification systems at present. Novel prognostic markers and models are urgently demanded. Aberrant lipid metabolism is closely related to the tumor progression but its prognostic significance in MTCLs remains unexplored. This study aims to investigate the relationship between dysregulated lipid metabolism and survival prognosis of MTCLs and establish a novel and well-performed prognostic scoring system for MTCL patients.

Methods

A total of 173 treatment-naive patients were enrolled in this study. Univariate and multivariate Cox regression analysis were performed to assess the prognostic significance of serum lipid profiles and screen out independent prognostic factors, which constituted a novel prognostic model for MTCLs. The performance of the novel model was assessed in the training and validation cohort, respectively, by examining its calibration, discrimination and clinical utility.

Results

Among the 173 included patients, 115 patients (01/2006–12/2016) constituted the training cohort and 58 patients (01/2017–06/2020) formed the validation cohort. Univariate analysis revealed declined total cholesterol (TC, P = 0.000), high-density lipoprotein cholesterol (HDL-C, P = 0.000) and increased triglycerides (TG, P = 0.000) correlated to inferior survival outcomes. Multivariate analysis revealed extranodal involved sites ≥ 2 (hazard ratio [HR]: 2.439; P = 0.036), β2-MG ≥ 3 mg/L (HR: 4.165; P = 0.003) and TC < 3.58 mmol/L (HR: 3.338; P = 0.000) were independent predictors. Subsequently, a novel prognostic model, EnBC score, was constructed with these three factors. Harrell’s C-index of the model in the training and validation cohort was 0.840 (95% CI 0.810–0.870) and 0.882 (95% CI 0.822–0.942), respectively, with well-fitted calibration curves. The model divided patients into four risk groups with distinct OS [median OS: not available (NA) vs. NA vs. 14.0 vs. 4.0 months, P < 0.0001] and PFS (median PFS: 84.0 vs. 19.0 vs. 8.0 vs. 1.5 months, P < 0.0001). Time-dependent receiver operating characteristic curve and decision curve analysis  further revealed that EnBC score provided higher diagnostic capacity and clinical benefit, compared with International Prognostic Index (IPI).

Conclusion

Firstly, abnormal serum lipid metabolism was demonstrated significantly related to the survival of MTCL patients. Furthermore, a lipid-covered prognostic scoring system was established and performed well in stratifying patients with MTCLs.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-02042-3.

Inhibition of Polo-like kinase 4 induces mitotic defects and DNA damage in diffuse large B-cell lymphoma

Polo-like kinase 4 (PLK4), a key regulator of centriole biogenesis, has recently been shown to play key roles in tumorigenesis. Blocking PLK4 expression by interference or targeted drugs exhibits attractive potential in improving the efficacy of chemotherapy. Nevertheless, the role of PLK4 in diffuse large B-cell lymphoma (DLBCL) is still undefined. In this study, we discover that PLK4 is a potential target for the treatment of DLBCL, and demonstrate the efficacy of a PLK4 inhibitor when used in combination with doxorubicin. Pharmaceutical inhibition of PLK4 with CFI-400945 inhibited DLBCL cell proliferation and induced apoptotic cell death. The anti-tumor effects were accompanied by mitotic defects, including polyploidy and cytokinesis failure. Activation of p53 and Hippo/YAP tumor suppressor signaling pathway was identified as the potential mechanisms driving CFI-400945 activity. Moreover, CFI-400945 treatment resulted in activation of DNA damage response. Combining CFI-400945 with doxorubicin markedly delayed tumor progression in DLBCL xenografts. Finally, PLK4 was increased in primary DLBCL tissues and cell lines. High levels of PLK4 expression were associated with poor survival in the patients receiving CHOP-based treatment, implicating PLK4 as a predictive biomarker of DLBCL chemosensitivity. These results provide the therapeutic potential of CFI-400945 both as monotherapy or in combination with doxorubicin for the treatment of DLBCL.

An Updated Understanding of the Role of YAP in Driving Oncogenic Responses

Simple Summary

In 2020, the global cancer database GLOBOCAN estimated 19.3 million new cancer cases worldwide. The discovery of targeted therapies may help prognosis and outcome of the patients affected, but the understanding of the plethora of highly interconnected pathways that modulate cell transformation, proliferation, invasion, migration and survival remains an ambitious goal. Here we propose an updated state of the art of YAP as the key protein driving oncogenic response via promoting all those steps at multiple levels. Of interest, the role of YAP in immunosuppression is a field of evolving research and growing interest and this summary about the current pharmacological therapies impacting YAP serves as starting point for future studies.

Abstract

Yes-associated protein (YAP) has emerged as a key component in cancer signaling and is considered a potent oncogene. As such, nuclear YAP participates in complex and only partially understood molecular cascades that are responsible for the oncogenic response by regulating multiple processes, including cell transformation, tumor growth, migration, and metastasis, and by acting as an important mediator of immune and cancer cell interactions. YAP is finely regulated at multiple levels, and its localization in cells in terms of cytoplasm–nucleus shuttling (and vice versa) sheds light on interesting novel anticancer treatment opportunities and putative unconventional functions of the protein when retained in the cytosol. This review aims to summarize and present the state of the art knowledge about the role of YAP in cancer signaling, first focusing on how YAP differs from WW domain-containing transcription regulator 1 (WWTR1, also named as TAZ) and which upstream factors regulate it; then, this review focuses on the role of YAP in different cancer stages and in the crosstalk between immune and cancer cells as well as growing translational strategies derived from its inhibitory and synergistic effects with existing chemo-, immuno- and radiotherapies.

Berberine exerts anti-tumor activity in diffuse large B-cell lymphoma by modulating c-myc/CD47 axis

Diffuse large B-cell lymphoma (DLBCL) is the most common subtype of non-Hodgkin lymphoma (NHL) with high clinical heterogeneity and poor prognosis. Immune escape mediated by CD47 overexpression contributes to the limited efficacy of rituximab, an anti-CD20 antibody, which indicates a target to improve the efficacy of DLBCL treatment. Here, we validated berberine, a natural compound, as a suppressor of CD47 and revealed the involved mechanism and biological function in DLBCL. Berberine downregulated the expression of CD47 in DLBCL at the transcriptional level by suppressing c-myc expression. Berberine-induced CD47 inhibition enhanced the phagocytosis of macrophages, thereby eliminating DLBCL cells in vitro and in vivo. Interestingly, berberine enhanced the efficiency of anti-CD47 antibody and rituximab-mediated phagocytosis. Moreover, a novel prognostic model based on the combination of CD47 and CD68, a biomarker of macrophages, was established in DLBCL. Our results highlighted for the first time that berberine could restore macrophage function in the tumor microenvironment, enhance rituximab-mediated phagocytosis and promote anti-CD47 antibody function via suppressing CD47 expression, which revealed a new anti-tumor mechanism of berberine and provided novel insights into the rituximab-based immunochemotherapy and CD47-targeted immunotherapy in DLBCL.

Circulating Exosomal MiR-107 Restrains Tumorigenesis in Diffuse Large B-Cell Lymphoma by Targeting 14-3-3η

Exosomes, nanometer-sized membranous vesicles in body fluids, have emerged as promising non-invasive biomarkers for cancer diagnosis. However, the function of exosomes in diffuse large B-cell lymphoma (DLBCL) remains elusive. This study aimed to investigate the role of exosomal miR-107 in lymphomagenesis and explore its clinical significance. In this study, decreased exosomal miR-107, miR-375-3p, and upregulated exosomal miR-485-3p were detected in the plasma of DLBCL patients and showed potential diagnostic value. Downregulated miR-107 expression was associated with advanced Ann Arbor stage, high IPI score, LDH, and β₂-MG level in DLBCL patients. Overexpression of miR-107 by miR-107 Agomir significantly abrogated cell proliferation, induced apoptosis, and inhibited cell invasion in vitro, and repressed tumor growth in vivo. Moreover, the downregulation of miR-107 went in the opposite direction. The target genes of miR-107 were mainly enriched in the PI3K-Akt, Hippo, and AMPK signaling pathways. Notably, upregulated 14-3-3η (YWHAH) was suppressed by miR-107 in DLBCL, suggesting that miR-107 may restrain tumorigenesis by targeting 14-3-3η. In summary, this study unveils the function of miR-107 in lymphomagenesis, highlighting its potential as a diagnostic and prognostic indicator and as a new therapeutic target in the management of DLBCL.

New Insights into YES-Associated Protein Signaling Pathways in Hematological Malignancies: Diagnostic and Therapeutic Challenges

Simple Summary

YES-associated protein (YAP) is a co-transcriptional activator that binds to transcriptional factors to increase the rate of transcription of a set of genes, and it can intervene in the onset and progression of different tumors. Most of the data in the literature refer to the effects of the YAP system in solid neoplasms. In this review, we analyze the possibility that YAP can also intervene in hematological neoplasms such as lymphomas, multiple myeloma, and acute and chronic leukemias, modifying the phenomena of cell proliferation and cell death. The possibilities of pharmacological intervention related to the YAP system in an attempt to use its modulation therapeutically are also discussed.

Abstract

The Hippo/YES-associated protein (YAP) signaling pathway is a cell survival and proliferation-control system with its main activity that of regulating cell growth and organ volume. YAP operates as a transcriptional coactivator in regulating the onset, progression, and treatment response in numerous human tumors. Moreover, there is evidence suggesting the involvement of YAP in the control of the hematopoietic system, in physiological conditions rather than in hematological diseases. Nevertheless, several reports have proposed that the effects of YAP in tumor cells are cell-dependent and cell-type-determined, even if YAP usually interrelates with extracellular signaling to stimulate the onset and progression of tumors. In the present review, we report the most recent findings in the literature on the relationship between the YAP system and hematological neoplasms. Moreover, we evaluate the possible therapeutic use of the modulation of the YAP system in the treatment of malignancies. Given the effects of the YAP system in immunosurveillance, tumorigenesis, and chemoresistance, further studies on interactions between the YAP system and hematological malignancies will offer very relevant information for the targeting of these diseases employing YAP modifiers alone or in combination with chemotherapy drugs.

The Interplay Between Non-coding RNAs and Insulin-Like Growth Factor Signaling in the Pathogenesis of Neoplasia

The insulin-like growth factors (IGFs) are polypeptides with similar sequences with insulin. These factors regulate cell growth, development, maturation, and aging via different processes including the interplay with MAPK, Akt, and PI3K. IGF signaling participates in the pathogenesis of neoplasia, insulin resistance, diabetes mellitus, polycystic ovarian syndrome, cerebral ischemic injury, fatty liver disease, and several other conditions. Recent investigations have demonstrated the interplay between non-coding RNAs and IGF signaling. This interplay has fundamental roles in the development of the mentioned disorders. We designed the current study to search the available data about the role of IGF-associated non-coding RNAs in the evolution of neoplasia and other conditions. As novel therapeutic strategies have been designed for modification of IGF signaling, identification of the impact of non-coding RNAs in this pathway is necessary for the prediction of response to these modalities.

Small extracellular vesicles with LncRNA H19 "overload": YAP Regulation as a Tendon Repair Therapeutic Tactic

Functional healing of tendon injuries remains a great challenge. Small extracellular vesicles (sEVs) have received attention as pro-regenerative agents. H19 overexpression could bring tendon regenerative ability, but the mechanism is still not fully elucidated, and reliable method for delivery of long non-coding RNAs (LncRNAs) was demanded. We identified the downstream mechanism of H19, the activation of yes-associated protein (YAP) via the H19-PP1-YAP axis. We established tendon stem/progenitor cells (TSPCs) stably overexpressing H19 with CRISPR-dCas9-based hnRNP A2/B1 activation (H19-CP-TSPCs). H19-OL-sEVs (H19 “overloading” sEVs) could be produced effectively from H19-CP-TSPCs. Only H19-OL-sEVs were able to significantly load large amounts of H19 rather than other competitors, and the potential of H19-OL-sEVs to promote tendon healing was far better than that of other competitors. Our study established a relatively reliable method for enrichment of LncRNAs into sEVs, providing new hints for modularized sEV-based therapies, and modularized sEVs represented a potential strategy for tendon regeneration.

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H19 overexpression enhances tendon regeneration

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H19 dephosphorylates and activates YAP

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hnRNP A2/B1 assists the enrichment of H19 into sEVs

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H19-OL-sEVs promote tendon regeneration

AMOT suppresses tumor progression via regulating DNA damage response signaling in diffuse large B-cell lymphoma

Angiomotin (AMOT) is a membrane protein that is aberrantly expressed in a variety of solid tumors. Accumulating evidence support that AMOT is involved in the pathological processes of tumor proliferation, apoptosis, and invasion. However, the potential role of AMOT in the pathogenesis of diffuse large B-cell lymphoma (DLBCL) remains elusive. In the present study, we investigated the expression level and biological function of AMOT in DLBCL. AMOT expression was significantly reduced in DLBCL biopsy section, and low AMOT expression was associated with poor clinical prognosis. Overexpression of AMOT by lentivirus in human DLBCL cells induced cell viability inhibition concomitant with an increased percentage of cells in G1 phase and decreased percentage in S phase. Moreover, AMOT upregulation increased the sensitivity of DLBCL cells to doxorubicin. Furthermore, overexpression of AMOT led to reduced activation of key kinases for the DNA damage response (DDR). The above results indicated that AMOT acts as a tumor suppressor via inhibition of the DDR, thus reducing the viability while increasing the chemosensitivity in DLBCL. In summary, AMOT may be a novel potential target for DLBCL therapeutic intervention.

The functions and clinical significance of circRNAs in hematological malignancies

With covalently closed circular structures, circular RNAs (circRNAs) were once misinterpreted as by-products of mRNA splicing. Being abundant, stable, highly conserved, and tissue-specific, circRNAs are recently identified as a type of regulatory RNAs. CircRNAs bind to certain miRNAs or proteins to participate in gene transcription and translation. Emerging evidence has indicated that the dysregulation of circRNAs is closely linked to the tumorigenesis and treatment response of hematological malignancies. CircRNAs play critical roles in various biological processes, including tumorigenesis, drug resistance, tumor metabolism, autophagy, pyroptosis, and ferroptosis. The N6-methyladenosine modification of circRNAs and discovery of fusion-circRNAs provide novel insights into the functions of circRNAs. Targeting circRNAs in hematological malignancies will be an attractive treatment strategy. In this review, we systematically summarize recent advances toward the novel functions and molecular mechanisms of circRNAs in hematological malignancies, and highlight the potential clinical applications of circRNAs as novel biomarkers and therapeutic targets for future exploration.