PWP1 is overexpressed in hepatocellular carcinoma and facilitates liver cancer cell proliferation.

Identification of novel biomarkers for prediction of disease course and prognosis is needed to reduce morbidity of liver hepatocellular carcinoma (LIHC/HCC) patients. Although dysregulated Periodic tryptophan protein 1 homolog (PWP1/endonuclein) expression has been detected in several tumors, the potential regulatory effect of PWP1 on LIHC remains uncertain. Here we evaluated the expression of PWP1 using multiple online platforms, and demonstrated that PWP1 upregulation was consistently observed in LIHC relative to non-tumor liver tissues and correlated with unfavorable prognosis. Moreover, HCC prognosis was significantly influenced by the methylation status of various CpG sites in the PWP1 gene. Lastly, we provide direct evidence that PWP1 acts as a driver of HCC progression by showing that siRNA-mediated PWP1 silencing significantly suppressed HCC cell proliferation in vitro. These data strongly suggest that PWP1 silencing may be an effective therapeutic strategy to treat LIHC.

DDX20 is required for cell-cycle reentry of prospermatogonia and establishment of spermatogonial stem cell pool during testicular development in mice.

RNA-binding proteins (RBPs), as key regulators of mRNA fate, are abundantly expressed in the testis. However, RBPs associated with human male infertility remain largely unknown. Through bioinformatic analyses, we identified 62 such RBPs, including an evolutionarily conserved RBP, DEAD-box helicase 20 (DDX20). Male germ-cell-specific inactivation of Ddx20 at E15.5 caused T1-propsermatogonia (T1-ProSG) to fail to reenter cell cycle during the first week of testicular development in mice. Consequently, neither the foundational spermatogonial stem cell (SSC) pool nor progenitor spermatogonia were ever formed in the knockout testes. Mechanistically, DDX20 functions to control the translation of its target mRNAs, many of which encode cell-cycle-related regulators, by interacting with key components of the translational machinery in prospermatogonia. Our data demonstrate a previously unreported function of DDX20 as a translational regulator of critical cell-cycle-related genes, which is essential for cell-cycle reentry of T1-ProSG and formation of the SSC pool.

GRSF1 predicts an unfavorable prognosis and promotes tumorigenesis in lung adenocarcinoma based on bioinformatics analysis and in vitro validation.

Background: Effective biomarkers play a critical role in improving clinical approaches to treat lung adenocarcinoma (LUAD). However, many existing biomarkers have limitations due to a lot of factors, requiring the development of additional biomarkers to effectively predict the disease course and prognosis of LUAD. Guanine-rich RNA sequence binding factor 1 (GRSF1) participates in multiple biological processes, but its regulatory effect on LUAD remains unknown. The present study aimed to investigate the clinicopathological importance and biological role of GRSF1 in LUAD. Methods: The expression of GRSF1 was evaluated using multiple service portals. X-Tile software were used to determine the high and low GRSF1 groups and the relationships between GRSF1 expression and clinicopathological characteristics were then analyzed by R packages. Besides, prognostic significance was identified by the Gene Expression Profiling Interactive Analysis 2 (GEPIA2) and Kaplan-Meier (K-M) Plotter. Overall survival (OS) and disease-free survival (DFS) was the main outcome of prognosis analysis. The DNA copy number alterations (CNAs) and methylations were calculated using cBioPortal and R packages. The co-expressed genes of GRSF1 were obtained from LinkedOmics, and functional networks were then constructed by R clusterProfiler. Additionally, cell counting kit 8 (CCK-8) and colony formation assays were applied to verify the proliferation effects of GRSF1 on LUAD cells. Results: GRSF1 was significantly upregulated in the LUAD tissues compared to the non-tumor lung tissues (all P<0.05), and its expression was significantly correlated with gender (χ2=6.873, P=0.009) and T classification (χ2=13.62, P=0.003). Higher GRSF1 expression indicated worse OS [hazards ratio (HR) =1.6, P=0.0022] and DFS (HR =1.4, P=0.043), which suggested that GRSF1 was an independent prognostic factor for LUAD. DNA gain/amplification and hypomethylation may also contribute to GRSF1 upregulation. The functional annotation showed that GRSF1 regulates tumorigenesis through several signaling pathways. The knockdown of GRSF1 significantly suppressed lung cancer cell proliferation in vitro. Conclusions: The high expression of GRSF1 indicated an unfavorable prognosis and was closely related to LUAD tumor occurrence and development, which could be used as an effective prognostic biomarker for patients suffering from LUAD.

RING finger 138 deregulation distorts NF-кB signaling and facilities colitis switch to aggressive malignancy.

Prolonged activation of nuclear factor (NF)-кB signaling significantly contributes to the development of colorectal cancer (CRC). New therapeutic opportunities are emerging from targeting this distorted cell signaling transduction. Here, we discovered the critical role of RING finger 138 (RNF138) in CRC tumorigenesis through regulating the NF-кB signaling, which is independent of its Ubiquitin-E3 ligase activity involved in DNA damage response. RNF138-/- mice were hyper-susceptible to the switch from colitis to aggressive malignancy, which coincided with sustained aberrant NF-кB signaling in the colonic cells. Furthermore, RNF138 suppresses the activation of NF-кB signaling pathway through preventing the translocation of NIK and IKK-Beta Binding Protein (NIBP) to the cytoplasm, which requires the ubiquitin interaction motif (UIM) domain. More importantly, we uncovered a significant correlation between poor prognosis and the downregulation of RNF138 associated with reinforced NF-кB signaling in clinical settings, raising the possibility of RNF138 dysregulation as an indicator for the therapeutic intervention targeting NF-кB signaling. Using the xenograft models built upon either RNF138-dificient CRC cells or the cells derived from the RNF138-dysregulated CRC patients, we demonstrated that the inhibition of NF-кB signaling effectively hampered tumor growth. Overall, our work defined the pathogenic role of aberrant NF-кB signaling due to RNF138 downregulation in the cascade events from the colitis switch to colonic neoplastic transformation and progression, and also highlights the possibility of targeting the NF-кB signaling in treating specific subtypes of CRC indicated by RNF138-ablation.

PDCD6 cooperates with C-Raf to facilitate colorectal cancer progression via Raf/MEK/ERK activation.

BACKGROUND: Colorectal cancer (CRC) is one of the most common malignancies, and it's expected that the CRC burden will substantially increase in the next two decades. New biomarkers for targeted treatment and associated molecular mechanism of tumorigenesis remain to be explored. In this study, we investigated whether PDCD6 plays an oncogenic role in colorectal cancer and its underlying mechanism. METHODS: Programmed cell death protein 6 (PDCD6) expression in CRC samples were analyzed by immunohistochemistry and immunofluorescence. The prognosis between PDCD6 and clinical features were analyzed. The roles of PDCD6 in cellular proliferation and tumor growth were measured by using CCK8, colony formation, and tumor xenograft in nude mice. RNA-sequence (RNA-seq), Mass Spectrum (MS), Co-Immunoprecipitation (Co-IP) and Western blot were utilized to investigate the mechanism of tumor progression. Immunohistochemistry (IHC) and quantitative real-time PCR (qRT-PCR) were performed to determine the correlation of PDCD6 and MAPK pathway. RESULTS: Higher expression levels of PDCD6 in tumor tissues were associated with a poorer prognosis in patients with CRC. Furthermore, PDCD6 increased cell proliferation in vitro and tumor growth in vivo. Mechanistically, RNA-seq showed that PDCD6 could affect the activation of the MAPK signaling pathway. PDCD6 interacted with c-Raf, resulting in the activation of downstream c-Raf/MEK/ERK pathway and the upregulation of core cell proliferation genes such as MYC and JUN. CONCLUSIONS: These findings reveal the oncogenic effect of PDCD6 in CRC by activating c-Raf/MEK/ERK pathway and indicate that PDCD6 might be a potential prognostic indicator and therapeutic target for patients with colorectal cancer.

Facile synthesis of mesoporous organosilica nanobowls with bridged silsesquioxane framework by one-pot growth and dissolution mechanism.

Mesoporous organosilica materials with organo-bridged silsesquioxane and novel structures have attracted great attention due to combined or enhanced properties. Here, we achieved facile synthesis of uniform well-defined mesoporous organosilica nanobowls with ethane- or ethane&thioether-bridged silsesquioxane framework by one-pot reaction. The possible formation mechanism may be attributed to be a dynamic growth, dissolution and reassembly process, including a uniform coating of ethane-bridged organosilica on the surface of mesoporous silica nanoparticles (MSNs) or mesoporous organosilica nanoparticles (MONs), gradual dissolution of MSNs or MONs core for the collapse of hollow spheres, and regrowth and reassembly of a small portion of the dissolved species. The framework stability of MSNs can be regulated by adjusting the amount of introduction of thioether-bridged silsesquioxane in the framework from 0 to 100%, which determines the structures of finally obtained products (nanobowls or rough nanoparticle (NPs)). The interesting results shed light on fundamental mechanisms of growth and dissolution for design and synthesis of novel structured materials. The ethane&thioether-bridged nanobowls show good hemocompatibility and low cytotoxicity compared with ethane-bridged nanobowls and calcined MCM-41-typed MSNs. The unique nanobowl structure, worm-like mesochannels and silsesquioxane framework make it as potential candidates for nanobiomedical applications.