Hippo pathway: Regulation, deregulation and potential therapeutic targets in cancer

Babaodan overcomes cisplatin resistance in cholangiocarcinoma via inhibiting YAP1

CONTEXT

Cholangiocarcinoma with highly heterogeneous, aggressive, and multidrug resistance has a poor prognosis. Although babaodan (BBD) combined with cisplatin improved non-small cell lung cancer efficacy, its impact on overcoming resistance in cholangiocarcinoma remains unexplored.

OBJECTIVE

This study explored the role and mechanism of BBD on cisplatin resistance in cholangiocarcinoma cells (CCAs).

MATERIALS AND METHODS

Cisplatin-resistant CCAs were exposed to varying concentrations of cisplatin (25-400 μg/mL) or BBD (0.25-1.00 mg/mL) for 48 h. IC50 values, inhibition ratios, apoptosis levels, DNA damage, glutathione (GSH) levels, oxidized forms of GSH, total GSH content, and glutaminase relative activity were evaluated using the cell counting kit 8, flow cytometry, comet assay, and relevant assay kits.

RESULTS

BBD-reduced the cisplatin IC50 in CCAs from 118.8 to 61.83 μg/mL, leading to increased inhibition rate, apoptosis, and DNA damage, and decreased expression of B-cell lymphoma-2, p-Yes-associated protein 1/Yes-associated protein 1, solute carrier family 1 member 5, activating transcription factor 4, and ERCC excision repair 1 in a dose-dependent manner with maximum reductions of 78.97%, 51.98%, 54.03%, 56.59%, and 63.22%, respectively; bcl2-associated X and gamma histone levels were increased by 0.43-115.77% and 22.15-53.39%. The impact of YAP1 knockdown on cisplatin-resistant CCAs resembled BBD. GSH, oxidized GSH species, total GSH content, and glutaminase activity in cisplatin-resistant CCAs with BBD treatment also decreased, while YAP1 overexpression countered BBD's effects.

DISCUSSION AND CONCLUSION

This study provides a scientific basis for BBD clinical application and provides a new direction for BBD biological mechanism research.

Differential isocitrate dehydrogenase 1 and isocitrate dehydrogenase 2 mutation-related landscape in intrahepatic cholangiocarcinoma

BACKGROUND

Patients with intrahepatic cholangiocarcinoma (ICC) are prone to recurrence and poor survival. Targeted therapy related to isocitrate dehydrogenase (IDH) is an extremely important treatment. IDH1 and IDH2 mutations are generally thought to have similar effects on the tumor landscape. However, it is doubtful whether these 2 mutations have exactly the same effects on tumor cells and the tumor microenvironment.

METHODS

All collected tumor samples were subjected to simultaneous whole-exon sequencing and proteome sequencing.

RESULTS

IDH1 mutations accounted for 12.2%, and IDH2 mutations accounted for 5.5%, all missense mutations. Tumors with IDH mutations had lower proportions of KRAS and TP53 mutations. Mutated genes were obviously enriched in the kinase pathway in the tumors with IDH2 mutations. The signaling pathways were mainly enriched in the activation of cellular metabolic activities and an increase of inhibitory immune cells in the tumors with IDH mutations. Moreover, tumors had unique enrichment in DNA repair in IDH1 mutants and secretion of biological molecules in IDH2 mutants. Inhibitory immune cells might be more prominent in IDH2 mutants, and the expression of immune checkpoints PVR and HLA-DQB1 was more prominent in IDH1 mutants. IDH mutants were more related to metabolism-related and inflammation-immune response clusters, and some belonged to the DNA replication and repair cluster.

CONCLUSIONS

These results revealed the differential IDH1 and IDH2 mutation-related landscapes, and we have provided an important reference database to guide ICC treatment.

PAX8-AS1/microRNA-25-3p/LATS2 regulates malignant progression of ovarian cancer via Hippo signaling

BACKGROUND

Ovarian cancer (OC) is a frequent malignancy of the female reproductive system. Recently, the aberrant expression of numerous lncRNAs has been confirmed as a key factor for cancer development. The regulatory role of PAX8-AS1 in some cancers has been investigated, but its role in OC progression remains unclear. This study focuses on the role and molecular mechanism of PAX8-AS1 in the malignant progression of OC.

METHODS

Bioinformatics means were adopted to analyze the expression of PAX8-AS1, microRNA-25-3p, and LATS2 in OC tissues and the binding sites between the three. qRT-PCR was employed to determine the expression of these genes in OC cells. CCK-8, colony formation, scratch healing, and Transwell assays were used to see cell viability, proliferation, migration, and invasion, respectively. Fluorescence in situ Hybridization was performed to probe the subcellular localization of PAX8-AS1. Western blot was applied to evaluate the expression and phosphorylation levels of YAP and TAZ, and an immunofluorescence assay was used to detect the translocation of them. Dual luciferase assay was applied to validate the binding relationship between PAX8-AS1 and microRNA-25-3p, as well as between microRNA-25-3p and LATS2.

RESULTS

PAX8-AS1 and LATS2 were lowly expressed. MicroRNA-25-3p was highly expressed in OC. PAX8-AS1 was expressed in cytoplasm and regulated LATS2 expression by sponging microRNA-25-3p. Overexpressing PAX8-AS1 can suppress the malignant behaviors of OC cells, whereas treatment with microRNA-mimic can reverse these results. In addition, the phosphorylation levels of YAP and TAZ increased upon oe-LATS2 treatment, and oe-LATS2 could promote YAP and TAZ translocate from the nucleus to cytoplasm. Rescue experiments demonstrated that sh-PAX8-AS1 fostered malignant progression of OC, which was reversed by simultaneous oe-LATS2.

CONCLUSION

In summary, PAX8-AS1/microRNA-25-3p/LATS2 regulated the malignant progression of OC through Hippo signaling, which suggested that PAX8-AS1/microRNA-25-3p/LATS2 axis may be a novel target for OC treatment.

The Impact of Cancer Stem Cells in Colorectal Cancer

Despite incessant research, colorectal cancer (CRC) is still one of the most common causes of fatality in both men and women worldwide. Over time, advancements in medical treatments have notably enhanced the survival rates of patients with colorectal cancer. Managing metastatic CRC involves a complex tradeoff between the potential benefits and adverse effects of treatment, considering factors like disease progression, treatment toxicity, drug resistance, and the overall impact on the patient's quality of life. An increasing body of evidence highlights the significance of the cancer stem cell (CSC) concept, proposing that CSCs occupy a central role in triggering cancer. CSCs have been a focal point of extensive research in a variety of cancer types, including CRC. Colorectal cancer stem cells (CCSCs) play a crucial role in tumor initiation, metastasis, and therapy resistance, making them potential treatment targets. Various methods exist for isolating CCSCs, and understanding the mechanisms of drug resistance associated with them is crucial. This paper offers an overview of the current body of research pertaining to the comprehension of CSCs in colorectal cancer.

Transcriptional regulation of cancer stem cell: regulatory factors elucidation and cancer treatment strategies

Cancer stem cells (CSCs) were first discovered in the 1990s, revealing the mysteries of cancer origin, migration, recurrence and drug-resistance from a new perspective. The expression of pluripotent genes and complex signal regulatory networks are significant features of CSC, also act as core factors to affect the characteristics of CSC. Transcription is a necessary link to regulate the phenotype and potential of CSC, involving chromatin environment, nucleosome occupancy, histone modification, transcription factor (TF) availability and cis-regulatory elements, which suffer from ambient pressure. Especially, the expression and activity of pluripotent TFs are deeply affected by both internal and external factors, which is the foundation of CSC transcriptional regulation in the current research framework. Growing evidence indicates that regulating epigenetic modifications to alter cancer stemness is effective, and some special promoters and enhancers can serve as targets to influence the properties of CSC. Clarifying the factors that regulate CSC transcription will assist us directly target key stem genes and TFs, or hinder CSC transcription through environmental and other related factors, in order to achieve the goal of inhibiting CSC and tumors. This paper comprehensively reviews the traditional aspects of transcriptional regulation, and explores the progress and insights of the impact on CSC transcription and status through tumor microenvironment (TME), hypoxia, metabolism and new meaningful regulatory factors in conjunction with the latest research. Finally, we present opinions on omnidirectional targeting CSCs transcription to eliminate CSCs and address tumor resistance.

GALNT2 targeted by miR-139-5p promotes proliferation of clear cell renal cell carcinoma via inhibition of LATS2 activation

Polypeptide N-Acetylgalactosaminyltransferase (GALNTs) are critical enzymes that initiate mucin type-O glycosylation, and are closely associated with the occurrence and development of multiple cancers. However, the significance of GALNT2 in clear cell renal cell carcinoma (ccRCC) progression remains largely undetermined. Based on public multi-omics analysis, GALNT2 was strongly elevated in ccRCC versus adjoining nontumor tissues, and it displayed a relationship with poor overall survival (OS) of ccRCC patients. In addition, GALNT2 over-expression accelerated proliferation of renal cancer cell (RCC) lines. In contrast, GALNT2 knockdown using shRNAs suppressed cell proliferation, and this was rescued by LATS2 knockdown. Similarly, GALNT2 deficiency enhanced p-LATS2/LATS2 expression. LATS2 is activated by phosphorylation (p-LATS2) and, in turn, phosphorylate the downstream substrate protein YAP. Phosphorylated YAP (p-YAP) stimulated its degradation and cytoplasmic retention, as it was unable to translocate to the nucleus. This resulted in reduced cell proliferation. Subsequently, we explored the upstream miRNAs of GALNT2. Using dual luciferase reporter assay, we revealed that miR-139-5p interacted with the 3' UTR of GALNT2. Low miR-139-5p expression was associated with worse ccRCC patient outcome. Based on our experiments, miR-139-5p overexpression inhibited RCC proliferation, and this phenotype was rescued by GALNT2 overexpression. Given these evidences, the miR-139-5p-GALNT2-LATS2 axis is critical for RCC proliferation, and it is an excellent candidate for a new therapeutic target in ccRCC.

A novel EIF3C-related CD8+ T-cell signature in predicting prognosis and immunotherapy response of nasopharyngeal carcinoma

PURPOSE

At present, dysfunctional CD8+ T-cells in the nasopharyngeal carcinoma (NPC) tumor immune microenvironment (TIME) have caused unsatisfactory immunotherapeutic effects, such as a low response rate of anti-PD-L1 therapy. Therefore, there is an urgent need to identify reliable markers capable of accurately predicting immunotherapy efficacy.

METHODS

Utilizing various algorithms for immune-infiltration evaluation, we explored the role of EIF3C in the TIME. We next found the influence of EIF3C expression on NPC based on functional analyses and RNA sequencing. By performing correlation and univariate Cox analyses of CD8+ Tcell markers from scRNA-seq data, we identified four signatures, which were then used in conjunction with the lasso algorithm to determine corresponding coefficients in the resulting EIF3C-related CD8+ T-cell signature (ETS). We subsequently evaluated the prognostic value of ETS using univariate and multivariate Cox regression analyses, Kaplan-Meier curves, and the area under the receiver operating characteristic curve (AUROC).

RESULTS

Our results demonstrate a significant relationship between low expression of EIF3C and high levels of CD8+ T-cell infiltration in the TIME, as well as a correlation between EIF3C expression and progression of NPC. Based on the expression levels of four EIF3C-related CD8+ T-cell marker genes, we constructed the ETS predictive model for NPC prognosis, which demonstrated success in validation. Notably, our model can also serve as an accurate indicator for detecting immunotherapy response.

CONCLUSION

Our findings suggest that EIF3C plays a significant role in NPC progression and immune modulation, particularly in CD8+ T-cell infiltration. Furthermore, the ETS model holds promise as both a prognostic predictor for NPC patients and a tool for adjusting individualized immunotherapy strategies.

Vitamin D-mediated tsRNA-07804 triggers mitochondrial dysfunction and suppresses non-small cell lung cancer progression by targeting CRKL

OBJECTIVE

tRNA-derived small RNAs (tsRNAs) are novel non-coding RNAs with various functions in multiple cancers. Nevertheless, whether vitamin D executes its function in mitochondrial dysfunction and non-small cell lung cancer (NSCLC) progression through tsRNAs remains obscure.

METHODS

Differentially expressed tsRNAs between control and vitamin D-treated H1299 cells were acquired by small RNA sequencing. Cell and animal experiments were implemented to elucidate the impacts of vitamin D and tsRNA on mitochondrial dysfunction and NSCLC progression. Dual-luciferase reporter assay, quantitative real-time PCR, western blot and recovery experiments were applied to determine the mechanism of tsRNA in NSCLC.

RESULTS

We discovered that vitamin D receptor resulted in decreased mitochondrial-related functions and vitamin D caused mitochondrial dysfunction of NSCLC cells. tsRNA-07804 was remarkably upregulated in vitamin D-treated H1299 cells. Functional experiments indicated that vitamin D led to mitochondrial dysfunction, repressed the proliferation, migration, invasion, and promoted apoptosis of H1299 cells via regulating tsRNA-07804. Mechanistically, tsRNA-07804 induced mitochondrial dysfunction and inhibited the malignancy of H1299 cells by suppressing CRKL expression. In vivo experiments showed that vitamin D inhibited the tumor growth in NSCLC by increasing tsRNA-07804 expression. Moreover, clinical sample analysis unveiled that tsRNA-07804 had a negative correlation with CRKL.

CONCLUSIONS

In conclusion, our study proved that vitamin D induced mitochondrial dysfunction and suppressed the progression of NSCLC through the tsRNA-07804/CRKL axis. Overall, these results unveiled that tsRNA-07804 might act as a potential therapeutic target for NSCLC.

Vemurafenib induces senescence in acute myeloid leukemia and myelodysplastic syndrome by activating the HIPPO signaling pathway: implications for potential targeted therapy

BACKGROUND

The outcome of Acute myeloid leukemia (AML) and myelodysplastic syndrome (MDS) remain dismal despite the development of treatment. Targeted therapy is gaining more and more attention in improving prognosis.

METHODS

Expression of BRAF was analyzed by RT-qPCR in AML and MDS patients. Cells viability treated by drugs was measured by CCK-8 assay. Network pharmacology and RNA-sequence were used to analyze the mechanism of drugs and verified in vitro and xenograft tumor model.

RESULTS

Here we showed that BRAF was overexpressed in AML and MDS patients, and correlated with poor prognosis. The BRAF inhibitor-Vemurafenib (VEM) could significantly induce senescence, proliferation inhibition and apoptosis in AML cells, which can be enhanced by Bortezomib (BOR). This inhibitory effect was also verified in CD34 + cells derived from AML patients. Mechanistically, we showed that VEM combined with BOR could turn on HIPPO signaling pathway, thereby inducing cellular senescence in AML cells and xenograft mouse.

CONCLUSIONS

Taken together, our findings demonstrate a significant upregulation of BRAF expression in AML and MDS patients, which is associated with unfavorable clinical outcomes. We also discovered that the BRAF inhibitor Vemurafenib induces cellular senescence through activation of the HIPPO signaling pathway. Analysis of BRAF expression holds promise as a prognostic indicator and potential therapeutic target for individuals with AML and MDS.

VEPH1 suppresses the progression of gastric cancer by regulating the Hippo-YAP signalling pathway

BACKGROUND

Ventricular zone-expressed PH domain-containing protein homologue 1 (VEPH1) is a recently discovered intracellular adaptor protein that plays an important role in human development. It has been reported that VEPH1 is closely related to the process of cellular malignancy, but its role in gastric cancer has not been elucidated. This study investigated the expression and function of VEPH1 in human gastric cancer (GC).

METHODS

We performed qRT‒PCR, Western blotting, and immunostaining assays in GC tissue samples to evaluate VEPH1 expression. Functional experiments were used to measure the malignancy of GC cells. A subcutaneous tumorigenesis model and peritoneal graft tumour model were established in BALB/c mice to determine tumour growth and metastasis in vivo.

RESULTS

VEPH1 expression is decreased in GC and correlates with the overall survival rates of GC patients. VEPH1 inhibits GC cell proliferation, migration, and invasion in vitro and suppresses tumour growth and metastasis in vivo. VEPH1 regulates the function of GC cells by inhibiting the Hippo-YAP signalling pathway, and YAP/TAZ inhibitor-1 treatment reverses the VEPH1 knockdown-mediated increase in the proliferation, migration and invasion of GC cells in vitro. Loss of VEPH1 is associated with increased YAP activity and accelerated epithelial-mesenchymal transition (EMT) in GC.

CONCLUSION

VEPH1 inhibited GC cell proliferation, migration, and invasion in vitro and in vivo and exerted its antitumour effects by inhibiting the Hippo-YAP signalling pathway and EMT process in GC.

Regulatory mechanism of macrophage polarization based on Hippo pathway

Macrophages are found to infiltrate and migrate in a large number of Tumor-associated macrophages (TMEs) and other macrophages in the microenvironment of tumors and related diseases, and undergo phenotypic changes in response to a variety of cytokines, mainly including the primary phenotype M2 and the anti-tumor phenotype M1. The Hippo signaling pathway affects the development of cancer and other diseases through various biological processes, such as inhibition of cell growth. In this review, we focus on immune cells within the microenvironment of tumors and other diseases, and the role of the Hippo pathway in tumors on macrophage polarization in the tumor microenvironment (TME) and other diseases.

ADCY6 is a potential prognostic biomarker and suppresses OTSCC progression via Hippo signaling pathway

Oral tongue squamous cell carcinoma (OTSCC) is a malignant tumor. Recently, studies have found that adenylate cyclase 6 (ADCY6) plays a pivotal role in many lethal tumors formation processes. The role of ADCY6 in OTSCC remains unknown. The expression of ADCY6 in OTSCC tissue samples was detected. The clinical significance of ADCY6 in OTSCC was analyzed by statistical methods. OTSCC cell lines were selected to analyze the biological function of ADCY6. Meanwhile, the effect of ADCY6 on the growth of OTSCC in vivo was explored using subcutaneous tumorigenesis assay. WB assay was used to detect the underlying signaling pathway. Cell function recovery test used to investigate the mechanism of ADCY6-promoting OTSCC malignant biological behavior via Hippo signaling pathway. We report that ADCY6 was obviously downregulated in OTSCC tissue samples and cell lines. Importantly, lower expression of ADCY6 indicates a poorer prognosis in patients with OTSCC, and its expression is significantly correlated with TNM stage and tumor size. Functionally, forced expression of ADCY6 can significantly inhibit the proliferation, migration, invasion, and promote apoptosis of OTSCC cells. Mechanistically, we demonstrated that ADCY6 upregulation impaired Hippo signaling pathway to reduce the malignant biological behavior of OTSCC. Generally, our findings suggest that ADCY6 suppressed Hippo signaling pathway to regulate malignant biological behavior in OTSCC, which provide new cues for further exploring the mechanism of occurrence and development of OTSCC.

Ca2+ signaling and the Hippo pathway: Intersections in cellular regulation

The Hippo signaling pathway is a master regulator of organ size and tissue homeostasis. Hippo integrates a broad range of cellular signals to regulate numerous processes, such as cell proliferation, differentiation, migration and mechanosensation. Ca2+ is a fundamental second messenger that modulates signaling cascades involved in diverse cellular functions, some of which are also regulated by the Hippo pathway. Studies published over the last five years indicate that Ca2+ can influence core Hippo pathway components. Nevertheless, comprehensive understanding of the crosstalk between Ca2+ signaling and the Hippo pathway, and possible mechanisms through which Ca2+ regulates Hippo, remain to be elucidated. In this review, we summarize the multiple intersections between Ca2+ and the Hippo pathway and address the biological consequences.

FN1 mediated activation of aspartate metabolism promotes the progression of triple-negative and luminal a breast cancer

BACKGROUND

Breast cancer (BC) is regarded as one of the most common cancers diagnosed among the female population and has an extremely high mortality rate. It is known that Fibronectin 1 (FN1) drives the occurrence and development of a variety of cancers through metabolic reprogramming. Aspartic acid is considered to be an important substrate for nucleotide synthesis. However, the regulatory mechanism between FN1 and aspartate metabolism is currently unclear.

METHODS

We used RNA sequencing (RNA seq) and liquid chromatography-mass spectrometry to analyze the tumor tissues and paracancerous tissues of patients. MCF7 and MDA-MB-231 cells were used to explore the effects of FN1-regulated aspartic acid metabolism on cell survival, invasion, migration and tumor growth. We used PCR, Western blot, immunocytochemistry and immunofluorescence techniques to study it.

RESULTS

We found that FN1 was highly expressed in tumor tissues, especially in Lumina A and TNBC subtypes, and was associated with poor prognosis. In vivo and in vitro experiments showed that silencing FN1 inhibits the activation of the YAP1/Hippo pathway by enhancing YAP1 phosphorylation, down-regulates SLC1A3-mediated aspartate uptake and utilization by tumor cells, inhibits BC cell proliferation, invasion and migration, and promotes apoptosis. In addition, inhibition of FN1 combined with the YAP1 inhibitor or SLC1A3 inhibitor can effectively inhibit tumor growth, of which inhibition of FN1 combined with the YAP1 inhibitor is more effective.

CONCLUSION

Targeting the "FN1/YAP1/SLC1A3/Aspartate metabolism" regulatory axis provides a new target for BC diagnosis and treatment. This study also revealed that intratumoral metabolic heterogeneity plays an important role in the progression of different subtypes of breast cancer.

YAP nuclear translocation facilitates radiation resistance in nasopharyngeal carcinoma cells

OBJECTIVES

Investigate the role of the Hippo-YAP signaling pathway in radioresistant Nasopharyngeal Carcinoma (NPC).

METHODS

Establishment of radioresistant CNE-1 cells (CNE-1-RR) by gradually increasing ionizing radiation (IR) doses, and identifying the apoptosis of CNE-1-RR by flow cytometry. We employed immunoblot and immunofluorescence staining to detect the expression of YAP in both CNE-1-RR and control group cells. Moreover, we validated the role of YAP in CNE-1-RR by inhibiting its nuclear translocation.

RESULTS

In contrast to the control group, radioresistant NPC cells demonstrated significant YAP dephosphorylation and nuclear translocation. CNE-1-RR cells exhibited enhanced activation of γ-H2AX (Ser139) upon exposure to IR and greater recruitment of double-strand breaks (DSBs) repair-related proteins. Additionally, inhibiting YAP nuclear translocation in radioresistant CNE-1-RR cells significantly increased their sensitivity to radiotherapy.

CONCLUSIONS

The present investigation has unveiled the intricate mechanisms and physiological roles of YAP in CNE-1-RR cells exhibiting resistance to IR. Based on our findings, it can be inferred that a combinational therapeutic strategy involving radiotherapy and inhibitors that impede the nuclear translocation of YAP holds promising potential for treating radioresistant NPC.

YAP inhibitor verteporfin suppresses tumor angiogenesis and overcomes chemoresistance in esophageal squamous cell carcinoma

PURPOSE

Targeting angiogenesis is an attractive strategy for the effective treatment of cancer. This study aimed to investigate the anti-cancer activities of YAP inhibitor verteporfin (VP) in esophageal squamous cell carcinoma (ESCC) cells through its inhibitory effect on tumor angiogenesis.

METHODS

Cell proliferation, apoptosis, migration and invasion abilities were estimated by MTT, colony formation, DAPI staining, wound healing and transwell assays, respectively. Human umbilical vein endothelial cell (HUVEC) tube formation assay and chick embryo chorioallantoic membrane (CAM) model were used to observe angiogenesis in vitro and in vivo. The interactions between ESCC cells and HUVECs were assessed by cell chemotactic migration and adhesion assays. The expression levels of angiogenesis-related molecules were detected by Western blot.

RESULTS

We found that VP was potential to inhibit ESCC cell proliferation, migration, invasion and induce apoptosis in the dose-dependent fashion. VP also significantly suppressed proliferation, migration, and tube formation of HUVECs and promoted apoptosis of HUVECs, and reduced angiogenesis in CAM. Moreover, VP inhibited ESCC cell-induced angiogenesis in vitro by decreasing HUVEC chemotactic migration, adhesion and tube formation, and also reduced ESCC cell-induced neovascularization of the CAM in vivo. In addition, VP suppressed the expression of pro-angiogenic molecules such as VEGFA, MMP-2 and β-catenin in ESCC cells. Furtherly, VP increased the chemosensitivity of ESCC-resistant cells to paclitaxel (PTX). The combination of VP and PTX attenuated the resistant cell-mediated angiogenesis in vitro and in vivo.

CONCLUSION

These results reveal for the first time that VP potently inhibits malignant progression and overcomes chemoresistance of ESCC cells via inhibition of tumor angiogenesis. It provides insight into a new strategy for the treatment of ESCC that VP could be a potential drug candidate for targeting tumor angiogenesis.

Chaetocin exhibits anticancer effects in esophageal squamous cell carcinoma via activation of Hippo pathway

Dysfunction of the Hippo pathway is common in esophageal squamous carcinoma (ESCC). Chaetocin, a small molecular compound isolated from the marine fungus, exhibits potent anticancer effects. However, the anticancer effects of chaetocin on ESCC and its potential relationship to Hippo pathway remain unclear. Here, we demonstrated that chaetocin dramatically inhibited the proliferation in ESCC cells by causing cycle arrest in the M phase and activating the caspase-dependent apoptosis signaling pathway in vitro, and we also found that chaetocin induced the accumulation cellular reactive oxygen species (ROS). The RNA-seq analysis indicated that the Hippo pathway is one of the most enriched pathways after chaetocin treatment. We further revealed that chaetocin triggered the activation of Hippo pathway in ESCC cells, which is characterized by elevated phosphorylation levels of almost all core proteins in Hippo pathway, such as MST1 (Thr183), MST2 (Thr180), MOB1 (Thr35), LAST1 (Thr1079 and Ser909) and YAP (Ser127), ultimately leading to decreased nuclear translocation of YAP. Moreover, the MST1/2 inhibitor XMU-MP-1 not only partially rescued the inhibitory effect chaetocin-induced proliferation, but also rescued the chaetocin-induced apoptosis in ESCC cells. Furthermore, in vivo results confirmed the antitumor effect of chaetocin and its relationship with Hippo pathway. Taken together, our study demonstrates that chaetocin exhibits anticancer effects in ESCC via activation of Hippo pathway. These results provide an important basis for further research of chaetocin as a potential candidate for ESCC treatment.

Breast Cancer Therapeutics and Hippo Signaling Pathway: Novel MicroRNA-Gene-Protein Interaction Networks

The Hippo signaling pathway is a master regulator of development, cell proliferation, and apoptosis in particular, and it plays an important role in tissue regeneration, controlling organ size, and cancer suppression. Dysregulation of the Hippo signaling pathway has been implicated in breast cancer, a highly prevalent cancer affecting 1 out of every 15 women worldwide. While the Hippo signaling pathway inhibitors are available, they are suboptimal, for example, due to chemoresistance, mutation, and signal leakage. Inadequate knowledge about the Hippo pathway connections and their regulators limits our ability to uncover novel molecular targets for drug development. We report here novel microRNA (miRNA)-gene and protein-protein interaction networks in the Hippo signaling pathway. We employed the GSE miRNA dataset for the present study. The GSE57897 dataset was normalized and searched for differentially expressed miRNAs, and their targets were searched using the miRWalk2.0 tool. From the upregulated miRNAs, we observed that the hsa-miR-205-5p forms the biggest cluster and targets four genes involved in the Hippo signaling pathway. Interestingly, we found a novel connection between two Hippo signaling pathway proteins, angiomotin (AMOT) and mothers against decapentaplegic homolog 4 (SMAD4). From the downregulated miRNAs, hsa-miR-16-5p, hsa-miR-7g-5p, hsa-miR-141-3p, hsa-miR-103a-3p, hsa-miR-21-5p, and hsa-miR-200c-3p, target genes were present in the pathway. We found that PTEN, EP300, and BTRC were important cancer-inhibiting proteins, form hubs, and their genes interact with downregulating miRNAs. We suggest that targeting proteins from these newly unraveled networks in the Hippo signaling pathway and further research on the interaction of hub-forming cancer-inhibiting proteins can open up new avenues for next-generation breast cancer therapeutics.

FTO promotes cervical cancer cell proliferation, colony formation, migration and invasion via the regulation of the BMP4/Hippo/YAP1/TAZ pathway

Cervical cancer is the fourth most common malignancy tumor worldwide with high incidence and mortality. Accumulating evidence indicated that through an m6A-dependent or m6A-independent mechanism, fat mass and obesity associated gene (FTO) exhibits the tumor-promoting and suppressive roles of FTO involved in various cancers, including cervical cancer. This study aims to verify the biological function and potential mechanisms of FTO in cervical cancer cell proliferation, colony formation, migration, and invasion in vitro as well as tumor growth in vivo. Herein, we confirmed that knockdown of FTO inhibits cell proliferation, colony formation, migration, and invasion of cervical cancer cells in vitro via cell counting kit-8 (CCK8) assay, colony formation assay, and transwell migration and invasion assay. The demethylase activity of FTO is required for cell proliferation, colony formation, migration, and invasion of cervical cancer cells in vitro. RNA sequencing, online database analysis, and western blotting revealed that FTO regulated the BMP4/Hippo/YAP1/TAZ pathway. In addition, FTO upregulates the expression of BMP4 in an m6A-dependent manner and binds to the N-terminal of BMP4 to form a dimer at the C-terminal in cervical cancer cells through protein-protein interaction. We further discovered that BMP4 treatment promoted cell proliferation, colony formation, migration, and invasion of cervical cancer cells, and rescue experiments validated that BMP4 treatment reversed the inhibition of FTO knockdown on the Hippo/YAP1/TAZ pathway and the progression of cervical cancer cells in vitro. Notably, the knockdown of FTO significantly suppressed xenograft tumor growth and the protein level of BMP4 in vivo. Collectively, our results demonstrate that the FTO promotes cervical cancer progression in vitro and in vivo via the regulation of the BMP4/Hippo/YAP1/TAZ pathway, suggesting that FTO acts as an oncogenic molecule and the FTO/BMP4 Hippo/YAP1/TAZ axis may serve as valuable targets for cervical cancer treatment.

Activating the Hippo pathway by nevadensin overcomes Yap-drived resistance to sorafenib in hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is a highly malignant type of tumor that is insensitive to cytotoxic chemotherapy and often develops drug resistance. Nevadensin, a bioflavonoid, exhibits anti-cancer properties in some cancers. However, the precise underlying mechanism of nevadensin against liver cancer are poorly understood. We aim to evaluate the efficacy as well as the molecular mechanism of nevadensin in the treatment of liver cancer.

METHODS

Effects of nevadensin on HCC cell proliferation and apoptosis were detected using EdU labeling and flow cytometry assays. The molecular mechanism of nevadensin on HCC was determined using RNAseq. The effects of nevadensin on hippo-Yap signaling were verified using western blot and RT-PCR.

RESULTS

In this study, we show that nevadensin significantly inhibits growth of HCC cells via inducing cell cycle arrest and apoptosis. RNAseq analysis showed that nevadensin regulates multiple functional signaling pathways associated with cancer including Hippo signaling. Western Blot analysis revealed that nevadensin notably induces activation of the MST1/2- LATS1/2 kinase in HCC cells, further resulting in the primary effector molecule YAP phosphorylation and subsequent degradation. These results indicated that nevadensin might exert its anti-HCC activity through the Hippo-ON mechanism. Moreover, nevadensin could increase the sensitivity of HCC cells to sorafenib by down-regulating YAP and its downstream targets.

CONCLUSIONS

The present study indicates that nevadensin could be a potential effective approach to treating HCC, and overcoming sorafeni resistance via inducing activation of Hippo signaling.

The Molecular Biology of Prostate Cancer Stem Cells: From the Past to the Future

Prostate cancer (PCa) continues to rank as the second leading cause of cancer-related mortality in western countries, despite the golden treatment using androgen deprivation therapy (ADT) or anti-androgen therapy. With decades of research, scientists have gradually realized that the existence of prostate cancer stem cells (PCSCs) successfully explains tumor recurrence, metastasis and therapeutic failure of PCa. Theoretically, eradication of this small population may improve the efficacy of current therapeutic approaches and prolong PCa survival. However, several characteristics of PCSCs make their diminishment extremely challenging: inherent resistance to anti-androgen and chemotherapy treatment, over-activation of the survival pathway, adaptation to tumor micro-environments, escape from immune attack and being easier to metastasize. For this end, a better understanding of PCSC biology at the molecular level will definitely inspire us to develop PCSC targeted approaches. In this review, we comprehensively summarize signaling pathways responsible for homeostatic regulation of PCSCs and discuss how to eliminate these fractional cells in clinical practice. Overall, this study deeply pinpoints PCSC biology at the molecular level and provides us some research perspectives.

Long noncoding RNA SNHG15: A promising target in human cancers

As oncogenes or tumor suppressor genes, lncRNAs played an important role in tumorigenesis and the progression of human cancers. The lncRNA SNHG15 has recently been revealed to be dysregulated in malignant tumors, suggesting the aberrant expression of which contributes to clinical features and regulates various oncogenic processes. We have selected extensive literature focused on SNHG15 from electronic databases, including studies relevant to its clinical significance and the critical events in cancer-related processes such as cell proliferation, apoptosis, autophagy, metastasis, and drug resistance. This review summarized the current understanding of SNHG15 in cancer, mainly focusing on the pathological features, known biological functions, and underlying molecular mechanisms. Furthermore, SNHG15 has been well-documented to be an effective diagnostic and prognostic marker for tumors, offering novel therapeutic interventions in specific subsets of cancer cells.

Ferroptosis and tumor immunotherapy: A promising combination therapy for tumors

Low response rate and treatment resistance are frequent problems in the immunotherapy of tumors, resulting in the unsatisfactory therapeutic effects. Ferroptosis is a form of cell death characterized by the accumulation of lipid peroxides. In recent years, it has been found that ferroptosis may be related to the treatment of cancer. Various immune cells (including macrophages and CD8⁺ T cells) can induce ferroptosis of tumor cells, and synergistically enhance the anti-tumor immune effects. However, the mechanisms are different for each cell types. DAMP released in vitro by cancer cells undergoing ferroptosis lead to the maturation of dendritic cells, cross-induction of CD8⁺ T cells, IFN-γ production and M1 macrophage production. Thus, it activates the adaptability of the tumor microenvironment and forms positive feedback of the immune response. It suggests that induction of ferroptosis may contribute to reducing resistance of cancer immunotherapy and has great potential in cancer therapy. Further research into the link between ferroptosis and tumor immunotherapy may offer hope for those cancers that are difficult to treat. In this review, we focus on the role of ferroptosis in tumor immunotherapy, explore the role of ferroptosis in various immune cells, and discuss potential applications of ferroptosis in tumor immunotherapy.

The role of Hippo pathway in ferroptosis

The role of Hippo pathway in ferroptosis The Hippo pathway is mainly composed of mammalian serine/threonine (Ste20)like kinases 1/2 (MST1/2), large tumor suppressor 1/2 (LATS1/2), and transcriptional coactivator Yes-associated protein (YAP), and is closely related to cell growth, survival, proliferation, and migration; tissue and organ size control; and tumorigenesis and development. Ferroptosis is a regulated form of cell death characterized by the accumulation of iron-dependent reactive oxygen species (ROS) and the depletion of plasma membrane polyunsaturated fatty acids (PUFAs), which is caused by the imbalance of oxidation and the antioxidant system. This article elaborates the role of Hippo pathway in ferroptosis, providing ideas for the regulation of cell fate and the treatment of tumors.

Antitumor Effects of Poplar Propolis on DLBCL SU-DHL-2 Cells

Propolis is resinous natural product produced by Western honeybees using beeswax and plant and bud exudates, which has a wide range of biological activities, including antioxidation, antibacterial, anti-inflammation, immune regulation, antitumor, and so on. Diffuse large B-cell lymphoma (DLBCL) is an aggressive cancer, and accounts for about 30% of all lymphomas. The effect of poplar propolis on DLBCL has not been reported. The IC₅₀ of propolis on the proliferation of DLBCL SU-DHL-2 cell line and its proteins and gene expressions were detected by CCK-8 kit, label-free proteomic, and RT-PCR. The results showed that the IC₅₀ of propolis at the 5 × l05/mL cell for 24 h was 5.729 μg/mL. Label-free-based proteomics analysis showed that there were 115 differentially expressed proteins (61 up-regulated and 54 down-regulated proteins) between IC₅₀ dose-treated and solvent control groups. There were 32.47% differential proteins located in the nucleus, 20.78% in the cytoplasm, and 14.29% in mitochondria. The most significant different pathway (p = 0.0016) of protein enrichment was ferroptosis (including glutamate-cysteine ligase regulatory subunit, ferritin, and heme oxygenase). The relative expression trend of 17 of the total 22 genes selected according to proteomics results was in line with their encoded protein. The highest protein-protein interaction was serine/threonine-protein kinase PLK, which interacted with 16 differential proteins. In conclusion, poplar propolis inhibited SU-DHL-2 cells via ferroptosis pathway, accelerating cell death and down-regulated serine/threonine-protein kinase PLK1, affecting apoptosis of cell. This result provides a theoretical basis for the treatment of DLBCL using propolis.

Targeting cancer stem cell pathways for lung cancer therapy

PURPOSE OF REVIEW

The unique properties of cancer stem cells (CSCs) make lung cancer untargetable for quite an extended period. The functional mechanism of this cell type has been illustrated step by step. However, the outcomes of lung cancer patients are still lower than expected clinically. The attempts made by scientists to make challenge history against stemness maintenance of lung cancer cells and their druggable targets are worth elucidating.

RECENT FINDINGS

Many agents, including the Bispecific T-cell engager (BiTE) and AMG 119 targeting DLL3-positive cells, are a tremendous breakthrough in the preclinical and clinical treatment of SCLC. More studies focus on targeting CSCs to overcome TKI resistance in NSCLC. The combo targeting of CSC and the immune microenvironment can favor the treatment of lung cancer patients.

SUMMARY

The current review elucidates the characteristics and related regulating pathways of lung CSCs from essential to preclinical research. We retrospectively introduce an update on the clinical development of therapeutics targeting CSC-associated developmental signaling pathways and discuss the opportunities to target CSC-immune interactions in lung cancer.

Hippo dictates signaling for cellular homeostasis and immune defense in Crassostrea hongkongensis hemocytes

Introduction

The Hippo signaling pathway is an evolutionarily conserved signaling cascade that plays a crucial role in regulating cell proliferation, differentiation, and apoptosis. It has been shown to be a key regulator of cell fate and cellular homeostasis in various immune processes. Despite its well-established functions in vertebrate immunity, its roles in marine invertebrate immunity remain poorly understood. Therefore, our present work provides fresh mechanistic insights into how the Hippo pathway orchestrates hemocytic functions in Crassostrea hongkongensis, with implications for studies on its major forms and modifications in animal evolution.

Method

The complete set of Hippo pathway genes, including SAV1, MOB1, LATS, YAP/TAZ, TEAD, and MST, were identified from the C. hongkongensis genome. Quantitative PCR assays were conducted to examine the mRNA expression levels of these genes in different tissues and the levels of these genes in hemocytes before and after bacterial challenges. The study also examined the crosstalk between the Hippo pathway and other immune pathways, such as the AP-1 and p53-dependent p21 signaling cascades. RNA interference was used to knock down MST and TEAD, and MST is a core orchestrator of non-canonical Hippo signaling, to investigate its impact on phagocytosis and bacterial clearance in hemocytes.

Result

The results demonstrated that members of the Hippo pathway were highly expressed in hemocytes, with their expression levels significantly increasing following bacterial challenges. Crosstalk between the Hippo pathway and other immune pathways triggered hemocytic apoptosis, which functioned similarly to the canonical Mst-Lats-Yap signaling pathway in Drosophila and mammals. Knocking down MST resulted in increased phagocytosis and boosted the efficiency of bacterial clearance in hemocytes, presumably due to mobilized antioxidant transcription by Nrf for maintaining immune homeostasis.

Discussion

This study provides novel insights into the regulatory mechanisms underlying the Hippo pathway in immune responses of C. hongkongensis hemocytes. The study highlights the importance of the Hippo pathway in maintaining immune homeostasis and orchestrating hemocytic functions in oysters. Moreover, this study demonstrates the divergence of the Hippo pathway's roles in marine invertebrate immunity from mammalian observations, indicating the need for further comparative studies across species. These findings have significant implications for future research aimed at elucidating the evolutionary trajectory and functional diversity of the Hippo signaling pathway in animal evolution.

A positive feedback loop of the TAZ/β-catenin axis promotes Helicobacter pylori-associated gastric carcinogenesis

Background

Helicobacter pylori infection is the strongest known risk factor for gastric cancer. The Hippo signaling pathway controls organ size and maintains tissue homeostasis by coordinately regulating cell growth and proliferation. Here, we demonstrate the interactive role of TAZ, the transcriptional coactivator of the Hippo pathway, and beta-catenin in promoting the pathogenesis of H. pylori infection.

Methods

TAZ expression was evaluated in human gastric tissues and H. pylori-infected insulin-gastrin (INS-GAS) mice. Western blot, immunofluorescence, immunohistochemistry, and RT-PCR assays were performed. Coimmunoprecipitation was performed to examine the interaction between TAZ and β-catenin. TAZ and β-catenin were silenced using small interfering RNAs. HA-β-catenin and Flag-TAZ were constructed.

Results

Increased TAZ was noted in human gastric cancer tissues compared to chronic gastritis tissues and in H. pylori-positive gastritis tissues compared to H. pylori-negative gastritis tissues. In addition, H. pylori infection induced TAZ expression and nuclear accumulation in the gastric tissue of INS-GAS mice and cultured gastric epithelial cells, which was dependent on the virulence factor CagA. Moreover, TAZ or β-catenin knockdown significantly suppressed H. pylori infection-induced cell growth, survival, and invasion. Furthermore, the interactive regulation of TAZ and β-catenin activation was revealed. Finally, β-catenin was required for H. pylori-induced TAZ activation.

Conclusion

These findings suggest the existence of a positive feedback loop of activation between TAZ and β-catenin that could play an important role in CagA+ H. pylori infection-induced gastric carcinogenesis. TAZ inhibition represents a potential target for the prevention of H. pylori infection-associated gastric cancer.

FBXO22 Accelerates Pancreatic Cancer Growth by Deactivation of the Hippo Pathway via Destabilizing LATS2

BACKGROUND

Dysregulation of ubiquitin ligases plays a crucial role in the development and progression of various human tumors. F-box only protein 22 (FBXO22), an F-box E3 ubiquitin ligase, has been reported to participate in diverse aspects of cancer progression. However, the clinical significance and biological function of FBXO22 in pancreatic cancer remain poorly understood.

AIMS

This study aimed to investigate the role of FBXO22 in promoting pancreatic cancer growth.

METHODS

FBXO22 expression was detected in pancreatic cancer and adjacent normal tissues using qRT-PCR, western blotting, and immunohistochemistry. Ectopic expression and knockdown of FBXO22 were performed to measure the impact on pancreatic cancer cells growth by CCK-8, colony formation, and tumorigenicity assay. Bioinformatics analysis uncovered the potential correlation between FBXO22 and various signaling pathways. Western blotting and immunoprecipitation were performed to identify FBXO22-interacting proteins.

RESULTS

We observed that FBXO22 was upregulated in samples obtained from patients with pancreatic cancer compared with its levels in the adjacent normal tissues, and an elevated FBXO22 level was obviously associated with poor prognosis among patients with pancreatic cancer. FBXO22 knockdown impaired pancreatic cancer cell growth both in vitro and in vivo, whereas FBXO22 overexpression accelerated pancreatic cancer cell growth. Furthermore, we found that FBXO22 contributed to pancreatic cancer cell growth by deactivating the Hippo pathway. Mechanistically, FBXO22 directly interacts with and destabilizes the large tumor suppressor 2 (LATS2), which is a critical regulator of the Hippo pathway. Blocking LATS2 leads to the loss of FBXO22-mediated oncogenic effect in pancreatic cancer.

CONCLUSIONS

These findings provide new insights into the upstream regulation of the Hippo pathway inactivation in pancreatic cancer growth and identify FBXO22 as a potential therapeutic target for this lethal malignant tumor.

Expression of the Hippo Pathway Core Components in Endometrial Cancer and Its Association with Clinicopathologic Features

BACKGROUND

The Hippo signaling pathway has a key role in tumorigenesis. This study aimed to evaluate the relationship between the expression of core components of the Hippo signaling pathway and its association with clinicopathological features in endometrial cancer.

MATERIALS AND METHODS

We retrospectively collected endometrioid endometrial cancer specimens from 60 patients between January 2002 and December 2009 at Gyeongsang National University Hospital. Relevant clinicopathological data were obtained through electronic medical records of patients. The expression patterns of six core components (YAP, p-YAP, LATS1/2, MST1/2, KIBRA, and Merlin) were identified by immunohistochemistry on tissue microarray sections.

RESULTS

The positive expression ratio was 75.0% for YAP, 73.3% for p-YAP, 26.7% for MST1/2, 16.7% for KIBRA, 15.0% for Merlin, and 15.0% for LATS1/2. YAP expression was negatively correlated with MST 1/2 kinases (p = 0.045) and positively correlated with p-YAP (p = 0.012). Merlin, and MST 1/2 kinases (p = 0.043) showed a positive correlation. A subgroup of patients aged below 60 years (p = 0.004) and with myometrial invasion depth of less than 1/2 (p = 0.041) showed a positive association with YAP expression. p-YAP expression was negatively associated with a subset of patients with primary tumour size ≥4 cm (p = 0.03). Logistic regression analysis showed a significant association between age and YAP expression. The odds ratio of p-YAP expression was significantly lower in the group with tumour size ≥4 cm.

CONCLUSION

Two prognostic factors, age and tumour size, were significantly associated with the expression of YAP and p-YAP in endometrial cancer. Further research should focus on their expression as a marker for prediction of clinicopathological implications in endometrial cancer.

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.

LncRNA MNX1-AS1 sustains inactivation of Hippo pathway through a positive feedback loop with USP16/IGF2BP3 axis in gallbladder cancer

The long non-coding RNAs (lncRNAs) have been implicated in multiple human cancers, which may offer great potential as putative targets for cancer diagnosis and treatment. However, the roles of most lncRNAs in gallbladder cancer (GBC) remain poorly understood. The objective of this research involves investigating the clinical implications and underlying mechanism of lncRNA motor neuron and pancreas homeobo×1 antisense RNA 1 (MNX1-AS1) in GBC. This study shows that MNX1-AS1 expression is elevated in the tissues of GBC patients, and is strongly associated with reduced patient survival. Functionally, MNX1-AS1 significantly stimulates the proliferation and metastasis of GBC cells in vitro and in vivo. Mechanistically, MNX1-AS1 is transcriptionally activated by TEA domain family member 4 (TEAD4), and suppresses insulin-like growing factor 2 mRNA-binding protein 3 (IGF2BP3) degradation by recruiting ubiquitin specific peptidase 16 (USP16). Furthermore, MNX1-AS1/IGF2BP3 axis inhibits the Hippo signaling pathway and subsequently activates TEAD4, thereby forming a positive feedback loop. According to our results, MNX1-AS1 facilitates tumorigenesis, progression and metastasis of GBC through a MNX1-AS1/IGF2BP3/Hippo pathway positive feedback loop, which could be both diagnostically and therapeutically helpful in GBC.

Tandem mass tag-based proteomics analysis of protein changes in the freezing and thawing cycles of Trachurus murphyi

We investigated the proteome variations in Trachurus murphyi with different cycles of freezing and thawing (FT) under frozen storage. A total of 2,482 proteins were assessed quantitatively, of which 269 proteins were recognized as differential abundance proteins during the second FT cycle until the eighth FT cycle. Bioinformatics analysis on gene ontology (GO) functional annotation and Kyoto Encyclopedia of Genes and Genomes pathway analyses of Differential Analysis of Proteins (DAPs) indicated multiple DAPs engaged with the protein structure, metabolic enzymes, and protein turnover. In addition, some of the observed proteins were probably the underlying markers of protein oxidation (PO). The analysis of PO sites revealed the sites of PO, such as amino adipic semialdehydes, γ-glutamic semialdehydes, and Schiff bases. Bioinformatics analyses demonstrated the involvement of differentially expressed proteins in the Hippo signaling pathway (Ko04390), indicating strong protein degradation with greater numbers of FT cycles under frozen storage. It provides an insight into quality stability from a proteomics quality perspective at the molecular level. The results obtained have deepened our current understandings of the mechanisms that reveal variations in proteomes and quality, as well as help promote quality control of T. murphyi across the cold transportation chain. PRACTICAL APPLICATION: Temperature fluctuation is one of the core issues during frozen food storage and distribution faced by the frozen food industry. Fluctuation may result in microstructural changes, ice recrystallization, and protein change in frozen food products. Tandem mass tag-based methods were adopted to study proteome variations in Trachurus murphyi muscles under different cycles of freezing and thawing under frozen storage conditions in this paper. The results obtained have deepened our current understandings of the mechanisms that reveal variations in proteomes and quality, as well as help promote quality control of T. murphyi across the cold transportation chain.

Discovery of N-benzylarylamide derivatives as novel tubulin polymerization inhibitors capable of activating the Hippo pathway

Novel N-benzylarylamide saderivatives were designed and synthesized, and their antiproliferative activities were explored. Some of 51 target compounds exhibited potent inhibitory activities against MGC-803, HCT-116 and KYSE450 cells with IC₅₀ values in two-digit nanomolar. Compound I-33 (MY-875) displayed the most potent antiproliferative activities against MGC-803, HCT-116 and KYSE450 cells (IC₅₀ = 0.027, 0.055 and 0.067 μM, respectively) and possessed IC₅₀ values ranging from 0.025 to 0.094 μM against other 11 cancer cell lines. Further mechanism studies indicated that compound I-33 (MY-875) inhibited tubulin polymerization (IC₅₀ = 0.92 μM) by targeting the colchicine bingding site of tubulin. Compound I-33 (MY-875) disrupted the construction of the microtubule networks and affected the mitosis in MGC-803 and SGC-7901 cells. In addition, although it acted as a colchicine binding site inhibitor, compound I-33 (MY-875) also activated the Hippo pathway to promote the phosphorylation status of MST and LATS, resulting in the YAP degradation in MGC-803 and SGC-7901 cells. Due to the degradation of YAP, the expression levels of TAZ and Axl decreased. Because of the dual actions on colchicine binding site and Hippo pathway, compound I-33 (MY-875) dose-dependently inhibited cell colony formatting ability, arrested cells at the G2/M phase and induced cells apoptosis in MGC-803 and SGC-7901 cells. Moreover, compound I-33 (MY-875) could regulate the levels of cell cycle and apoptosis regulatory proteins in MGC-803 and SGC-7901 cells. Furthermore, molecular docking analysis suggested that the hydrogen bond and hydrophobic interactions made compound I-33 (MY-875) well bind into the colchicine binding site of tubulin. Collectively, compound I-33 (MY-875) is a novel anti-gastric cancer agent and deserves to be further investigated for cancer therapy by targeting the colchicine binding site of tubulin and activating the Hippo pathway.

Molecular Alterations in Malignant Pleural Mesothelioma: A Hope for Effective Treatment by Targeting YAP

Malignant pleural mesothelioma is a rare and aggressive neoplasm, which has primarily been attributed to the exposure to asbestos fibers (83% of cases); yet, despite a ban of using asbestos in many countries, the incidence of malignant pleural mesothelioma failed to decline worldwide. While little progress has been made in malignant pleural mesothelioma diagnosis, bevacizumab at first, then followed by double immunotherapy (nivolumab plus ipilumumab), were all shown to improve survival in large phase III randomized trials. The morphological analysis of the histological subtyping remains the primary indicator for therapeutic decision making at an advanced disease stage, while a platinum-based chemotherapy regimen combined with pemetrexed, either with or without bevacizumab, is still the main treatment option. Consequently, malignant pleural mesothelioma still represents a significant health concern owing to poor median survival (12-18 months). Given this context, both diagnosis and therapy improvements require better knowledge of the molecular mechanisms underlying malignant pleural mesothelioma's carcinogenesis and progression. Hence, the Hippo pathway in malignant pleural mesothelioma initiation and progression has recently received increasing attention, as the aberrant expression of its core components may be closely related to patient prognosis. The purpose of this review was to provide a critical analysis of our current knowledge on these topics, the main focus being on the available evidence concerning the role of each Hippo pathway's member as a promising biomarker, enabling detection of the disease at earlier stages and thus improving prognosis.

Role of IQ Motif-Containing GTPase-Activating Proteins in Hepatocellular Carcinoma

IQ motif-containing GTPase-activating proteins (IQGAPs) are a class of scaffolding proteins, including IQGAP1, IQGAP2, and IQGAP3, which govern multiple cellular activities by facilitating cytoskeletal remodeling and cellular signal transduction. The role of IQGAPs in cancer initiation and progression has received increasing attention in recent years, especially in hepatocellular carcinoma (HCC), where the aberrant expression of IQGAPs is closely related to patient prognosis. IQGAP1 and 3 are upregulated and are considered oncogenes in HCC, while IQGAP2 is downregulated and functions as a tumor suppressor. This review details the three IQGAP isoforms and their respective structures. The expression and role of each protein in different liver diseases and mainly in HCC, as well as the underlying mechanisms, are also presented. This review also provides a reference for further studies on IQGAPs in HCC.

A Four-Gene Prognostic Signature Based on the TEAD4 Differential Expression Predicts Overall Survival and Immune Microenvironment Estimation in Lung Adenocarcinoma

Background: TEA domain transcription factor 4 (TEAD4) is a member of the transcriptional enhancer factor (TEF) family of transcription factors, which is studied to be linked to the tumorigenesis and progression of various forms of cancers, including lung adenocarcinoma (LUAD). However, the specific function of this gene in the progression of LUAD remains to be explored.

Method: A total of 19 genes related to the Hippo pathway were analyzed to identify the significant genes involved in LUAD progression. The TCGA-LUAD data (n = 585) from public databases were mined, and the differentially expressed genes (DEGs) in patients with the differential level of TEAD4 were identified. The univariate Cox regression, zero LASSO regression coefficients, and multivariate Cox regression were performed to identify the independent prognostic signatures. The immune microenvironment estimation in the two subgroups, including immune cell infiltration, HLA family genes, and immune checkpoint genes, was assessed. The Gene Set Enrichment Analysis (GSEA) and GO were conducted to analyze the functional enrichment of DEGs between the two risk groups. The potential drugs for the high-risk subtypes were forecasted via the mode of action (moa) module of the connectivity map (CMap) database.

Results:TEAD4 was found to be significantly correlated with poor prognosis in LUAD-patients. A total of 102 DEGs in TEAD4-high vs. TEAD4-low groups were identified. Among these DEGs, four genes (CPS1, ANLN, RHOV, and KRT6A) were identified as the independent prognostic signature to conduct the Cox risk model. The immune microenvironment estimation indicated a strong relationship between the high TEAD4 expression and immunotherapeutic resistance. The GSEA and GO showed that pathways, including cell cycle regulation, were enriched in the high-risk group, while immune response-related and metabolism biological processes were enriched in the low-risk group. Several small molecular perturbagens targeting CFTR or PLA2G1B, by the mode of action (moa) modules of the glucocorticoid receptor agonist, cyclooxygenase inhibitor, and NFkB pathway inhibitor, were predicted to be suited for the high-risk subtypes based on the high TEAD4 expression.

Conclusion: The current study revealed TEAD4 is an immune regulation–related predictor of prognosis and a novel therapeutic target for LUAD.

Hippo: a new hub for atherosclerotic disease

Abstract:

Hippo,an evolutionarily conserved kinase cascade reaction in organisms,can respond to a set of signals,such as mechanical signals and cell metabolism,to maintain cell growth,differentiation,tissue/organ development and homeostasis.In the past ten years,HIPPO has controlled the development of tissues and organs by regulating the process of cell proliferation,especially in the field of cardiac regeneration after myocardial infarction.This suggests that HIPPO signaling is closely linked to cardiovascular disease.Atherosclerosis is the most common disease of the cardiovascular system. It is characterised by chronic inflammation of the vascular wall, mainly involving dysfunction of endothelial cells, smooth muscle cells and macrophages.Oxidized Low density lipoprotein (LDL) damages the barrier function of endothelial cells, which enter the middle membrane of the vascular wall, accelerates the formation of foam cells and promotes the occurrence and development of atherosclerosis.Autophagy is associated with the development of atherosclerosis.However, the mechanism of HIPPO regulation of atherosclerosis has not meant to clarified.In view of the pivotal role of this signaling pathway in maintaining cell growth,proliferation and differentiation,the imbalance of Hippo is related to atherosclerosis and related diseases.In this review,we emphasized Hippo as a hub for regulating atherosclerosis and discussed its potential targets in pathophysiology,human diseases,and related pharmacology.

Cinobufacini Injection Inhibits the Proliferation of Triple-Negative Breast Cancer Through the Pin1-TAZ Signaling Pathway

Triple-negative breast cancer (TNBC) is an aggressive subtype of breast cancer (BC), which is characterized by the total absence of human epidermal growth factor receptor 2 (HER2), progesterone receptor (PR), and estrogen receptor (ER) expression. Cinobufacini injection (CI) is the aqueous extract from the dry skin of Bufo gargarizans, which is broadly used for the treatment of malignant tumors. However, the potential mechanism of CI against TNBC has not been fully revealed. In this study, we found that CI inhibited the proliferation of MDA-MB-231 and 4T1 cells in a time- and dose-dependent manner. RNA-seq data showed that downregulated and upregulated genes were mainly enriched in biological processes related to tumor cell proliferation, including cell cycle arrest and regulation of apoptosis signaling pathways. Indeed, after CI treatment, the protein level of CDK1 and Bcl-2/Bax decreased, indicating that CI induced the cell cycle of MDA-MB-231 arrest in the G2/M phase and increased the rate of apoptosis. Meanwhile, CI significantly inhibited the growth of tumor in vivo, and RNA-seq data showed that the TAZ signaling pathway played a vital role after CI treatment. Both immunohistochemistry and Western blot analysis confirmed the downregulation of Pin1 and TAZ, caused by CI treatment. Furthermore, the bioinformatics analysis indicated that Pin1 and TAZ were indeed elevated in TNBC patients, with poor staging, classification, and patient survival rate. In conclusion, CI effectively inhibited the proliferation of TNBC in vitro and in vivo and induced their apoptosis and cycle arrest through the Pin1–TAZ pathway.

Potential neurotoxicity, immunotoxicity, and carcinogenicity induced by metribuzin and tebuconazole exposure in earthworms (Eisenia fetida) revealed by transcriptome analysis

Metribuzin and tebuconazole have been widely used in agriculture for several decades. Apart from endocrine disruption, little is known about their toxicological effects on organisms without thyroid organs, at the transcriptional level. To explore this toxicity, model earthworm species Eisenia fetida, hatched from the same cocoon and cultured under identical environmental conditions, were independently exposed to the two chemicals at non-lethal concentrations in OECD artificial soil for 48 h after exposure. RNA-seq technology was used to analyze and compare the gene expression profiles of earthworms exposed to metribuzin and tebuconazole. The functions of differentially expressed genes and their standard response patterns of upregulated and downregulated expression for both pesticides were verified. The findings demonstrated that metribuzin and tebuconazole are both potentially toxic to earthworms. Toxicological effects mainly involved the nervous system, immune system, and tumors, at the transcriptional level, as well as the induction of cytochrome P450-dependent detoxification and oxidative stress. In addition, the mitogen-activated protein kinase kinase kinase gene was identified as a biomarker, and the mitogen-activated protein kinase signaling pathway was verified to be a part of the adverse outcome pathway of metribuzin and tebuconazole and their structural analogs.

CHRNA5 Contributes to Hepatocellular Carcinoma Progression by Regulating YAP Activity

Hepatocellular carcinoma (HCC) is a major health concern worldwide. A better understanding of the mechanisms underlying the malignant phenotype is necessary for developing novel therapeutic strategies for HCC. Signaling pathways initiated by neurotransmitter receptors, such as α5-nicotinic acetylcholine receptor (CHRNA5), have been reported to be implicated in tumor progression. However, the functional mechanism of CHRNA5 in HCC remains unclear. In this study, we explored the role of CHRNA5 in HCC and found that CHRNA5 expression was increased in human HCC tissues and positively correlated with the T stage (p < 0.05) and AJCC phase (p < 0.05). The KM plotter database showed that the high expression level of CHRNA5 was strongly associated with worse survival in HCC patients. Both in vitro and in vivo assays showed that CHRNA5 regulates the proliferation ability of HCC by regulating YAP activity. In addition, CHRNA5 promotes the stemness of HCC by regulating stemness-associated genes, such as Nanog, Sox2 and OCT4. Cell migration and invasion assays demonstrated that CHRNA5 significantly enhanced the metastasis of HCC by regulating epithelial–mesenchymal transition (EMT)-associated genes. Furthermore, we found that CHRNA5 regulates the sensitivity of sorafenib in HCC. Our findings suggest that CHRNA5 plays a key role in the progression and drug resistance of HCC, and targeting CHRNA5 may be a strategy for the treatment of HCC.

CLDN6 Suppresses c-MYC-Mediated Aerobic Glycolysis to Inhibit Proliferation by TAZ in Breast Cancer

Claudin 6 (CLDN6) was found to be a breast cancer suppressor gene, which is lowly expressed in breast cancer and inhibits breast cancer cell proliferation upon overexpression. However, the mechanism by which CLDN6 inhibits breast cancer proliferation is unclear. Here, we investigated this issue and elucidated the molecular mechanisms by which CLDN6 inhibits breast cancer proliferation. First, we verified that CLDN6 was lowly expressed in breast cancer tissues and that patients with lower CLDN6 expression had a worse prognosis. Next, we confirmed that CLDN6 inhibited breast cancer proliferation through in vitro and in vivo experiments. As for the mechanism, we found that CLDN6 inhibited c-MYC-mediated aerobic glycolysis based on a metabolomic analysis of CLDN6 affecting cellular lactate levels. CLDN6 interacted with a transcriptional co-activator with PDZ-binding motif (TAZ) and reduced the level of TAZ, thereby suppressing c-MYC transcription, which led to a reduction in glucose uptake and lactate production. Considered together, our results suggested that CLDN6 suppressed c-MYC-mediated aerobic glycolysis to inhibit the proliferation of breast cancer by TAZ, which indicated that CLDN6 acted as a novel regulator of aerobic glycolysis and provided a theoretical basis for CLDN6 as a biomarker of progression in breast cancer.

The Role of MicroRNAs in Therapeutic Resistance of Malignant Primary Brain Tumors

Brain tumors in children and adults are challenging tumors to treat. Malignant primary brain tumors (MPBTs) such as glioblastoma have very poor outcomes, emphasizing the need to better understand their pathogenesis. Developing novel strategies to slow down or even stop the growth of brain tumors remains one of the major clinical challenges. Modern treatment strategies for MPBTs are based on open surgery, chemotherapy, and radiation therapy. However, none of these treatments, alone or in combination, are considered effective in controlling tumor progression. MicroRNAs (miRNAs) are 18-22 nucleotide long endogenous non-coding RNAs that regulate gene expression at the post-transcriptional level by interacting with 3'-untranslated regions (3'-UTR) of mRNA-targets. It has been proven that miRNAs play a significant role in various biological processes, including the cell cycle, apoptosis, proliferation, differentiation, etc. Over the last decade, there has been an emergence of a large number of studies devoted to the role of miRNAs in the oncogenesis of brain tumors and the development of resistance to radio- and chemotherapy. Wherein, among the variety of molecules secreted by tumor cells into the external environment, extracellular vesicles (EVs) (exosomes and microvesicles) play a special role. Various elements were found in the EVs, including miRNAs, which can be transported as part of these EVs both between neighboring cells and between remotely located cells of different tissues using biological fluids. Some of these miRNAs in EVs can contribute to the development of resistance to radio- and chemotherapy in MPBTs, including multidrug resistance (MDR). This comprehensive review examines the role of miRNAs in the resistance of MPBTs (e.g., high-grade meningiomas, medulloblastoma (MB), pituitary adenomas (PAs) with aggressive behavior, and glioblastoma) to chemoradiotherapy and pharmacological treatment. It is believed that miRNAs are future therapeutic targets in MPBTs and such the role of miRNAs needs to be critically evaluated to focus on solving the problems of resistance to therapy this kind of human tumors.

The regulatory networks of the Hippo signaling pathway in cancer development

The Hippo signaling pathway is a relatively young tumor-related signaling pathway. Although it was discovered lately, research on it developed rapidly. The Hippo signaling pathway is closely relevant to the occurrence and development of tumors and the maintenance of organ size and other biological processes. This manuscript focuses on YAP, the core molecule of the Hippo signaling pathway, and discussion the upstream and downstream regulatory networks of the Hippo signaling pathway during tumorigenesis and development. It also summarizes the relevant drugs involved in this signaling pathway, which may be helpful to the development of targeted drugs for cancer therapy.

Inhibition of fibronectin accumulation suppresses tumor growth

Understanding how the extracellular matrix affects cancer development constitutes an emerging research field. Fibronectin and collagen are two intriguing matrix components found in cancer. Large concentrations of fibronectin or collagen type I have been implicated in poor prognosis in patients. In a mouse model, we had shown that genetically decreasing circulating fibronectin resulted in smaller tumors. We therefore aimed to manipulate fibronectin pharmacologically and determine how cancer development is affected. Deletion of fibronectin in human breast cancer cells (MDA-MB-231) using shRNA (knockdown: Kd) improved survival and diminished tumor burden in a model of metastatic lesions and in a model of local growth. Based on these findings, it seemed reasonable to attempt to prevent fibronectin accumulation using a bacterial derived peptide called pUR4. Treatment with this peptide for 10 days in the breast cancer local growth model or for 5 days in a melanoma skin cancer model (B16) was associated with a significant suppression of cancer growth. Treatment aimed at inhibiting collagen type I accumulation without interfering with fibronectin could not affect any changes in vivo. In the absence of fibronectin, diminished cancer progression was due to inhibition of proliferation, even though changes in blood vessels were also detected. Decreased proliferation could be attributed to decreased ERK phosphorylation and diminished YAP expression. In summary, manipulating fibronectin diminishes cancer progression, mostly by suppressing cell proliferation. This suggests that matrix modulation could be used as an adjuvant to conventional therapy as long as a decrease in fibronectin is obtained.