RACO-1 modulates Hippo signalling in oesophageal squamous cell carcinoma

Molecular Mechanism of WWOX Inhibiting the Development of Esophageal Cancer by Inhibiting Hippo Signaling Pathway

With the emergence of combined surgical treatments, complemented by radiotherapy and chemotherapy, survival rates for esophageal cancer patients have improved, but the overall 5-year survival rate remains low. Therefore, there is an urgent need for further research into the pathogenesis of esophageal cancer and the development of effective prevention, diagnosis, and treatment methods. We initially utilized the GeneCards and DisGeNET databases to identify the esophageal cancer-associated gene WWOX (WW domain containing oxidoreductase). Subsequently, we employed RT-qPCR (Reverse transcription-quantitative PCR) and WB (western blot) to investigate the differential expression of WWOX in HEEC (human esophageal endotheliocytes) and various ESCC (esophageal squamous cell carcinoma) cell lines. We further evaluated alterations in cell proliferation, migration and apoptosis via CCK8 (cell counting kit-8) and clonal formation, Transwell assays and flow cytometry. Additionally, we investigated changes in protein expressions related to the Hippo signaling pathway (YAP/TEAD) through RT-qPCR and WB. Lastly, to further elucidate the regulatory mechanism of WWOX in ESCC, we performed exogenous YAP rescue experiments in ESCC cells with WWOX overexpression to investigate the alterations in apoptosis and proliferation. Results indicated that the expression of WWOX in ESCC was significantly downregulated. Subsequently, upon overexpression of WWOX, ESCC cell proliferation and migration decreased, while apoptosis increased. Additionally, the expression of YAP and TEAD were reduced. However, the sustained overexpression of YAP attenuated the inhibitory effects of WWOX on ESCC cell malignancy. In conclusion, WWOX exerts inhibitory effects on the proliferation and migration of ESCC and promotes apoptosis by suppressing the Hippo signaling pathway. These findings highlight the potential of WWOX as a novel target for the diagnosis and treatment of esophageal cancer.

Role of Hippo pathway dysregulation from gastrointestinal premalignant lesions to cancer

BACKGROUND

First identified in Drosophila melanogaster, the Hippo pathway is considered a major regulatory cascade controlling tissue homeostasis and organ development. Hippo signaling components include kinases whose activity regulates YAP and TAZ final effectors. In response to upstream stimuli, YAP and TAZ control transcriptional programs involved in cell proliferation, cytoskeletal reorganization and stemness.

MAIN TEXT

While fine tuning of Hippo cascade components is essential for maintaining the balance between proliferative and non-proliferative signals, pathway signaling is frequently dysregulated in gastrointestinal cancers. Also, YAP/TAZ aberrant activation has been described in conditions characterized by chronic inflammation that precede cancer development, suggesting a role of Hippo effectors in triggering carcinogenesis. In this review, we summarize the architecture of the Hippo pathway and discuss the involvement of signaling cascade unbalances in premalignant lesions of the gastrointestinal tract, providing a focus on the underlying molecular mechanisms.

CONCLUSIONS

The biology of premalignant Hippo signaling dysregulation needs further investigation in order to elucidate the evolutionary trajectories triggering cancer inititation and develop effective early therapeutic strategies targeting the Hippo/YAP pathway.

E3 ubiquitin ligase RNF187 promotes growth of spermatogonia via lysine 48-linked polyubiquitination-mediated degradation of KRT36/KRT84

Ubiquitination is the most common post-translational modification and is essential for various cellular regulatory processes. RNF187, which is known as RING domain AP1 coactivator-1, is a member of the RING finger family. RNF187 can promote the proliferation and migration of various tumor cells. However, whether it has a similar role in regulating spermatogonia is not clear. This study explored the role and molecular mechanism of RNF187 in a mouse spermatogonia cell line (GC-1). We found that RNF187 knockdown reduced the proliferation and migration of GC-1 cells and promoted their apoptosis. RNF187 overexpression significantly increased the proliferation and migration of GC-1 cells. In addition, we identified Keratin36/Keratin84 (KRT36/KRT84) as interactors with RNF187 by co-immunoprecipitation and mass spectrometry analyses. RNF187 promoted GC-1 cell growth by degrading KRT36/KRT84 via lysine 48-linked polyubiquitination. Subsequently, we found that KRT36 or KRT84 overexpression significantly attenuated proliferation and migration of RNF187-overexpressing GC-1 cells. In summary, our study explored the involvement of RNF187 in regulating the growth of spermatogonia via lysine 48-linked polyubiquitination-mediated degradation of KRT36/KRT84. This may provide a promising new strategy for treating infertility caused by abnormal spermatogonia development.

Roles of oncogenes in esophageal squamous cell carcinoma and their therapeutic potentials

Esophageal squamous cell carcinoma (ESCC) is the most common type of esophageal cancer (EC) in Asia. It is a malignant digestive tract tumor with abundant gene mutations. Due to the lack of specific diagnostic markers and early cancer screening markers, most patients are diagnosed at an advanced stage. Genetic and epigenetic changes are closely related to the occurrence and development of ESCC. Here, We review the activation of proto-oncogenes into oncogenes through gene mutation and gene amplification in ESCC from a genetic and epigenetic genome perspective, We also discuss the specific regulatory mechanisms through which these oncogenes mainly affect the biological function and occurrence and development of ESCC through specific regulatory mechanisms. In addition, we summarize the clinical application value of these oncogenes is summarized, and it provides a feasible direction for clinical use as potential therapeutic and diagnostic markers.

C12orf59 Promotes Esophageal Squamous Cell Carcinoma Progression via YAP-Mediated Epithelial-Mesenchymal Transition

C12orf59 is a novel gene widely expressed in diverse normal human tissues. Aberrant expression of C12orf59, which is involved in tumor progression, has been reported in a few types of cancer. However, its expression and biological function in esophageal squamous cell carcinoma (ESCC) remain largely unclear. Here, we found that the mRNA and protein levels of C12orf59 were prominently higher in both tumor tissues and most ESCC cell lines. Functionally, C12orf59 overexpression promoted ESCC cell proliferation, migration and invasion, whereas C12orf59 depletion worked oppositely. Mechanistically, C12orf59 exerted its oncogenic function through the induction of epithelial-mesenchymal transition (EMT) of ESCC cells, which relied on Yes-associated protein (YAP) dephosphorylation and nuclear translocation. Constitutively active YAP further facilitated cell migration, invasion and EMT induced by enforced C12orf59 overexpression. On the contrary, increased cell motility and EMT caused by enforced C12orf59 overexpression were dramatically repressed upon YAP inactivation by verteporfin. Thus, we conclude that YAP activation driven by C12orf59 contributes to the malignancy of ESCC through EMT and that targeting drugs for C12orf59 combined with YAP inhibitor may be a potential therapeutic strategy for ESCC.

HJURP regulates cell proliferation and chemo-resistance via YAP1/NDRG1 transcriptional axis in triple-negative breast cancer

Triple-negative breast cancer is still a difficult point in clinical treatment at present, and a deep study of its pathogenesis has great clinical value. Therefore, our research mainly focuses on exploring the progression of triple-negative breast cancer and determines the important role of the HJURP/YAP1/NDRG1 transcriptional regulation axis in triple-negative breast cancer. We observed significantly increased HJURP expression levels in triple-negative breast cancer compared to other subtypes. HJURP could affect the level of ubiquitination modification of YAP1 protein and then regulate its downstream transcriptional activity. Mechanistically, we found that YAP1 positively regulates NDRG1 transcription by binding the promoter region of the NDRG1 gene. And HJURP/YAP1/NDRG1 axis could affect cell proliferation and chemotherapy sensitivity in triple-negative breast cancer. Taken together, these findings provide insights into the transcriptional regulation axis of HJURP/YAP1/NDRG1 in triple-negative breast cancer progression and therapeutic response.

Dysregulation of miR-144-5p/RNF187 axis contributes to the progression of colorectal cancer

Background and Objectives

RING finger protein 187 (RNF187) belongs to RING domain-containing E3 ligases family, which was recently reported to be involved in oncogenesis and development of several cancers. This research aims to clarify the role of RNF187 in colorectal cancer (CRC) development.

Methods

The expression of RNF187 and miR-144-4p were determined by quantitative real-time polymerase chain reaction (qRT-PCR). The levels of RNF187 protein were assessed by western blot analysis. Cell Counting Kit-8 (CCK8) assay, clonogenic assay, cell scratch test and transwell assay were used to determine the proliferation, migration and invasion of CRC cells in vitro. The binding of miR-144-5p and RNF197 mRNA was validated by luciferase reporter assays. Tumor-bearing nude mice were used to determine CRC cells growth in vivo.

Results

RNF187 expression significantly increased in CRC specimens and cell lines compared to normal colon tissues and normal colonic mucosa cell line, respectively. Upregulation of RNF187 expression was inversely correlated to poor prognosis in CRC patients. In addition, knockdown of RNF187 expression inhibited the proliferation, migration, and invasion but promoted the apoptosis of CRC lines Caco-2 and SW480 cells. Further studies validated that RNF187 was the direct target of miR-144-5p. The expression of miR-144-5p was downregulated in CRC tissues, which was negatively correlated to the expression of RNF187. Restoration of miR-144-5p significantly inhibited the progression of CRC cells and its anti-tumor effects could be abrogated by overexpression of RNF187.

Conclusion

Our findings demonstrate the deregulation of miR-144-5p/ RNF187 axis in CRC, as well as its role in regulation of the tumor progression, thus providing a novel therapeutic strategy for CRC treatment.

RACO-1 modulates Hippo signalling in oesophageal squamous cell carcinoma

Oesophageal cancer is one of the most lethal malignancies worldwide, whereas the 5-year survival is less than 20%. Although the detailed carcinogenic mechanisms are not totally clear, recent genomic sequencing data showed dysregulation of Hippo signalling could be a critical factor for oesophageal squamous cell carcinoma (ESCC) progression. Therefore, understanding of the molecular mechanisms that control Hippo signalling activity is of great importance to improve ESCC diagnostics and therapeutics. Our current study revealed RACO-1 as an inhibitory protein for YAP/TEAD axis. Depletion of RACO-1 increases the protein level of YAP and expression of YAP/TEAD target gene. Besides, RACO-1 silencing could promote ESCC cell invasion and migration, which effect could be rescued by YAP depletion in ESCC cells. Immunoprecipitation showed that RACO-1 associated with YAP and promote ubiquitination and degradation of YAP at k48 poly-ubiquitination site. Our research discovered a new regulator of Hippo signalling via modulating YAP stability. RACO-1 could be a promising factor, which serves cancer diagnostics and therapeutics in ESCC patients.