Paip1 overexpression is involved in the progression of gastric cancer and predicts shorter survival of diagnosed patients

Knockdown of PAIP1 Inhibits Breast Cancer Cell Proliferation by Regulating Cyclin E2 mRNA Stability

Polyadenylate-binding protein-interacting protein 1 (PAIP1) is a protein that modulates translation initiation in eukaryotic cells. Studies have shown that PAIP1 was overexpressed in various type of cancers, and drives cancer progression by promoting cancer cell proliferation, invasion, and migration. In our previous study, we identified that PAIP1 was overexpressed in breast cancer, and the expression was correlated with poor prognosis. However, the biological function of PAIP1 in breast cancer has not been clearly understood. In this study, we constructed PAIP1 specifically silenced breast cancer cells. Then, cell proliferation, cell cycle distribution, and apoptosis were detected in PAIP1 knockdown cells. RNA-seq analysis was performed to predict the downstream target of PAIP1, and the molecular mechanism was explored. As a results, we found that knockdown of PAIP1 repressed cell proliferation, induced cell cycle arrest, and triggers apoptosis. Xenograft mouse model showed that knockdown of PAIP1 inhibits cell growth in vivo. RNA-seq predicted that CCNE2 mRNA was one of the downstream targets of PAIP1. In addition, we identified that knockdown of PAIP1-inhibited cell proliferation through modulating cyclin E2 expression. Mechanically, knockdown of PAIP1 reduces the expression of cyclin E2 by regulating the mRNA stability of cyclin E2. Moreover, in breast cancer tissues, we found that the expression of PAIP1 was positively correlated with cyclin E2. Taken together, our findings establish the role and mechanism of PAIP1 in breast cancer progression, indicating that PAIP1 would be a new therapeutic target for breast cancer treatment.

Unveiling the role of microRNAs in metabolic dysregulation of Gestational Diabetes Mellitus

Gestational Diabetes Mellitus (GDM) presents a significant health concern globally, necessitating a comprehensive understanding of its metabolic intricacies for effective management. MicroRNAs (miRNAs) have emerged as pivotal regulators in GDM pathogenesis, influencing glucose metabolism, insulin signaling, and lipid homeostasis during pregnancy. Dysregulated miRNA expression, both upregulated and downregulated, contributes to GDM-associated metabolic abnormalities. Ethnic and temporal variations in miRNA expression underscore the multifaceted nature of GDM susceptibility. This review examines the dysregulation of miRNAs in GDM and their regulatory functions in metabolic disorders. We discuss the involvement of specific miRNAs in modulating key pathways implicated in GDM pathogenesis, such as glucose metabolism, insulin signaling, and lipid homeostasis. Furthermore, we explore the potential diagnostic and therapeutic implications of miRNAs in GDM management, highlighting the promise of miRNA-based interventions for mitigating the adverse consequences of GDM on maternal and offspring health.

Loss of Paip1 causes translation reduction and induces apoptotic cell death through ISR activation and Xrp1

Regulation of protein translation initiation is tightly associated with cell growth and survival. Here, we identify Paip1, the Drosophila homolog of the translation initiation factor PAIP1, and analyze its role during development. Through genetic analysis, we find that loss of Paip1 causes reduced protein translation and pupal lethality. Furthermore, tissue specific knockdown of Paip1 results in apoptotic cell death in the wing imaginal disc. Paip1 depletion leads to increased proteotoxic stress and activation of the integrated stress response (ISR) pathway. Mechanistically, we show that loss of Paip1 promotes phosphorylation of eIF2α via the kinase PERK, leading to apoptotic cell death. Moreover, Paip1 depletion upregulates the transcription factor gene Xrp1, which contributes to apoptotic cell death and eIF2α phosphorylation. We further show that loss of Paip1 leads to an increase in Xrp1 translation mediated by its 5'UTR. These findings uncover a novel mechanism that links translation impairment to tissue homeostasis and establish a role of ISR activation and Xrp1 in promoting cell death.

PAIP1 regulates expression of immune and inflammatory response associated genes at transcript level in liver cancer cell

Poly(A) binding protein interacting protein 1 (PAIP1) is a translation regulator and also regulate the decay of mRNA. PAIP1 has also been reported to be a marker of increased invasive potential of liver cancer. However, the roles and underlying molecular mechanism of PAIP1 in liver cancer is still unclear. Here, cell viability and the gene expression profile of liver cancer line HepG2 transfected with PAIP1 siRNA was compared with cells transfected with non-targeting control siRNA. The results showed that PAIP1 knockdown inhibited cell viability, and extensively affects expression of 893 genes at transcriptional level in HepG2 cells. Gene function analysis showed that a large number of PAIP1 up-regulated genes were enriched in term of DNA-dependent transcription and the down-regulated genes were enriched in some pathways including immune response and inflammatory response. qPCR confirmed that PAIP1 knockdown positively regulated the expression of selected immune and inflammatory factor genes in HepG2 cells. Expression analysis of TCGA revealed that PAIP1 had positive correlations with two immune associated genes IL1R2 and PTAFR in liver tumor tissue. Taken together, our results demonstrated that PAIP1 was not only a translation regulator, but also a transcription regulator in liver cancer. Moreover, PAIP1 could function as a regulatory factor of immune and inflammatory genes in liver cancer. Thus, our study provides important cues for further study on the regulatory mechanism of PAIP1 in liver cancer.

Human Proteome Microarray identifies autoantibodies to tumor-associated antigens as serological biomarkers for the diagnosis of hepatocellular carcinoma

The identification of the high-efficiency and non-invasive biomarkers for hepatocellular carcinoma (HCC) detection is urgently needed. This study aims to screen out potential autoantibodies to tumor-associated antigens (TAAbs) and to assess their diagnostic value for HCC. Fifteen potential TAAbs were screened out from the Human Proteome Microarray by 30 HCC sera and 22 normal control sera, of which eight passed multiple-stage validations by ELISA with a total of 1625 human serum samples from normal controls (NCs) and patients with HCC, liver cirrhosis, chronic hepatitis B, gastric cancer, esophageal cancer, and colorectal cancer. Finally, an immunodiagnostic model including six TAAbs (RAD23A, CAST, RUNX1T1, PAIP1, SARS, PRKCZ) was constructed by logistic regression, and yielded the area under curve (AUC) of 0.835 and 0.788 in training and validation sets, respectively. The serial serum samples from HCC model mice were tested to explore the change in TAAbs during HCC formation, and an increasing level of autoantibodies was observed. In conclusion, the panel of six TAAbs can provide potential value for HCC detection, and the strategy to identify novel serological biomarkers can also provide new clues in understanding immunodiagnostic biomarkers.

Circ_0005576 Exerts an Oncogenic Role in Cervical Cancer via miR-1305-Dependent Regulation of PAIP1

Cervical cancer (CC) is a leading cause of high morbidity and mortality in women worldwide. Circular RNAs (circRNAs) are considered to be essential regulators of various cancers, including CC. The purpose of this study was to investigate the role and mechanism of circ_0005576 in CC progression. The levels of circ_0005576, miR-1305, and poly(A)-binding protein-interacting protein 1 (PAIP1) were detected by quantitative real-time PCR (qRT-PCR) or western blot assay. The stability and location of circ_0005576 were determined by ribonuclease R (RNase R) assay and subcellular fractionation distribution assay, respectively. Cell proliferation was evaluated by CCK-8 assay, EDU incorporation assay, and colony formation assay. Cell migration and invasion were assessed by transwell assay. The interactions between miR-1305 and circ_0005576 or PAIP1 were validated by dual-luciferase reporter assay. The protein expression of cyclin D1, vimentin, and matrix metallopeptidase 9 (MMP9) was tested by western blot. Moreover, mice xenograft models were constructed to analyze tumor growth in vivo. Circ_0005576 and PAIP1 were upregulated, while miR-1305 was downregulated in CC tissues and cells. Circ_0005576 was a stable circRNA that was mainly distributed in the cytoplasm of cells. Knockdown of circ_0005576 suppressed the proliferation, migration, and invasion of CC cells, while the silence of miR-1305 facilitated the development of CC cells. Meanwhile, circ_0005576 could sponge miR-1305 to promote PAIP1 expression. Furthermore, PAIP1 overexpression relieved the influence of circ_0005576 silence on the growth of CC cells. Additionally, circ_0005576 silence hindered CC tumor growth in vivo. Circ_0005576 depletion suppressed tumor development in CC by regulating the miR-1305/PAIP1 axis, suggesting that circ_0005576 might be a potential biomarker for CC treatment.

Effect of PAIP1 on the metastatic potential and prognostic significance in oral squamous cell carcinoma

Poly Adenylate Binding Protein Interacting protein 1 (PAIP1) plays a critical role in translation initiation and is associated with the several cancer types. However, its function and clinical significance have not yet been described in oral squamous cell carcinoma (OSCC) and its associated features like lymph node metastasis (LNM). Here, we used the data available from Gene Expression Omnibus (GEO), The Cancer Genome Atlas (TCGA), and Clinical Proteomic Tumor Analysis Consortium (CPTAC) to analyze PAIP1 expression in oral cancer. The publicly available data suggests that PAIP1 mRNA and protein levels were increased in OSCC. The high PAIP1 expression was more evident in samples with advanced stage, LNM, and worse pattern of invasion. Moreover, the in vitro experiments revealed that PAIP1 knockdown attenuated colony forming, the aggressiveness of OSCC cell lines, decreasing MMP9 activity and SRC phosphorylation. Importantly, we found a correlation between PAIP1 and pSRC through the analysis of the IHC scores and CPTAC data in patient samples. Our findings suggest that PAIP1 could be an independent prognostic factor in OSCC with LNM and a suitable therapeutic target to improve OSCC patient outcomes.

Integration of gene co-expression analysis and multi-class SVM specifies the functional players involved in determining the fate of HTLV-1 infection toward the development of cancer (ATLL) or neurological disorder (HAM/TSP)

Human T-cell Leukemia Virus type-1 (HTLV-1) is an oncovirus that may cause two main life-threatening diseases including a cancer type named Adult T-cell Leukemia/Lymphoma (ATLL) and a neurological and immune disturbance known as HTLV-1 Associated Myelopathy/Tropical Spastic Paraparesis (HAM/TSP). However, a large number of the infected subjects remain as asymptomatic carriers (ACs). There is no comprehensive study that determines which dysregulated genes differentiate the pathogenesis routes toward ATLL or HAM/TSP. Therefore, two main algorithms including weighted gene co-expression analysis (WGCNA) and multi-class support vector machines (SVM) were utilized to find major gene players in each condition. WGCNA was used to find the highly co-regulated genes and multi-class SVM was employed to identify the most important classifier genes. The identified modules from WGCNA were validated in the external datasets. Furthermore, to find specific modules for ATLL and HAM/TSP, the non-preserved modules in another condition were found. In the next step, a model was constructed by multi-class SVM. The results revealed 467, 3249, and 716 classifiers for ACs, ATLL, and HAM/TSP, respectively. Eventually, the common genes between the WGCNA results and classifier genes resulted from multi-class SVM that also determined as differentially expressed genes, were identified. Through these step-wise analyses, PAIP1, BCAS2, COPS2, CTNNB1, FASLG, GTPBP1, HNRNPA1, RBBP6, TOP1, SLC9A1, JMY, PABPC3, and PBX1 were found as the possible critical genes involved in the progression of ATLL. Moreover, FBXO9, ZNF526, ERCC8, WDR5, and XRCC3 were identified as the conceivable major involved genes in the development of HAM/TSP. These genes can be proposed as specific biomarker candidates and therapeutic targets for each disease.

mRNPs: Structure and role in development

In eukaryotic cells, mRNA molecules are coated with numerous RNA-binding proteins and so exist in ribonucleoproteins (mRNPs). The proteins associated with the mRNA regulate the fate of mRNA, including its localization, translation and decay. Before activation of translation, the mRNA does not display any template functions-it is masked. The coordinated activity of certain RNA-binding proteins determines the future fate of each mRNA individually. In embryo development, the temporal and spatial regulation of translation can cause a situation when the mRNA and the encoded protein are localized in different compartments and so the differentiation of the cells can be determined. The fundamentals of regulation of the mRNAs fate and functioning in nerves are similar to those already described for oo- and embryogenesis. Disorders in the mRNA masking and demasking result in the emergence of various diseases, in particular cancers and neuro-degenerative diseases.

High Paip1 Expression as a Potential Prognostic Marker in Hepatocellular Carcinoma

BACKGROUND/AIM

Translation plays an important role in the carcinogenesis of various human tumors. Paip1 and eIF4A1 are translation-associated proteins that mediate the function of eukaryotic initiation factor 4F complex. This study aimed to analyse the relationship between the expression status of Paip1 and eIF4A1 and clinicopathologic features in hepatocellular carcinoma (HCC).

MATERIALS AND METHODS

Immunohistochemical analysis was used to evaluate the expression status of Paip1 and eIF4A1. Two pathologists independently interpreted the immunostained slides. The prognostic value of Paip1 and eIF4A1 was evaluated by the Kaplan-Meier plotter.

RESULTS

Among 173 HCC patients, 28 (16.1%) and 46 (26.6%) belonged in the Paip1 and eIF4A1 high-expression groups. High expression of Paip1 and eIF4A1 was associated with advanced TNM stage and more frequent vascular tumor invasion. Univariate analysis indicated that high Paip1 expression was associated with worse five-year overall survival (OS). Public dataset analysis by Kaplan-Meier plotter revealed that high mRNA expression of Paip1, and not of eIF4A1, was significantly associated with worse five-year OS and disease-free survival.

CONCLUSION

Paip1 expression has a potential prognostic value in human HCC.

Upregulation of PAIP1 promotes the gallbladder tumorigenesis through regulating PLK1 level

Background

Increasing evidence suggests that elevated expression of polyA-binding protein-interacting protein 1 (PAIP1) is associated with cancer development and progression. However, how PAIP1 promotes gallbladder cancer (GBC) is still unclear.

Methods

Two GBC tissue-derived cell lines, NOZ and GBC-SD cells, were used in this study. Assays of cell proliferation, colony formation, apoptosis, and xenograft tumor model were performed to examine the tumorigenic effects of PAIP1. Immunohistochemical (IHC) staining was used to examine the expression level of PAIP1 in both patient GBC tissues and mouse tumors. Microarray and bioinformatics analysis were used to explore the targets of PAIP1. Quantitative polymerase chain reaction (qPCR) and western blot analysis were used to validate PAIP1-mediated targets.

Results

We found that upregulated PAIP1 expression was correlated with GBC. Knockdown of PAIP1 in gallbladder cells alleviated cell proliferation, promoted apoptosis, and inhibited xenograft tumor growth. Gene microarray analysis showed that stable silencing of PAIP1 altered various gene expressions. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis suggested that PAIP1 regulates cell cycle progression. Finally, we found that the PLK1 kinase, a key regulator of cell cycle, was regulated by PAIP1 at the transcriptional and protein levels. PLK1 level was positively correlated with PAIP1 level in both mouse tumors and GBC tissues. PAIP1 interacted with PLK1, and rescue of PAIP1 could recover PLK1 protein level and inhibit apoptosis.

Conclusions

Our data suggest that PAIP1 contributes to GBC progression likely through regulating PLK1 level. Since upregulated PAIP1 expression is positively associated with GBC, PAIP1 may act as a clinical prognostic biomarker of GBC.

MiRNAs in Gestational Diabetes Mellitus: Potential Mechanisms and Clinical Applications

Gestational diabetes mellitus (GDM) is a common pregnancy complication which is normally diagnosed in the second trimester of gestation. With an increasing incidence, GDM poses a significant threat to maternal and offspring health. Therefore, we need a deeper understanding of GDM pathophysiology and novel investigation on the diagnosis and treatment for GDM. MicroRNAs (miRNAs), a class of endogenic small noncoding RNAs with a length of approximately 19-24 nucleotides, have been reported to exert their function in gene expression by binding to proteins or being enclosed in membranous vesicles, such as exosomes. Studies have investigated the roles of miRNAs in the pathophysiological mechanism of GDM and their potential as noninvasive biological candidates for the management of GDM, including diagnosis and treatment. This review is aimed at summarizing the pathophysiological significance of miRNAs in GDM development and their potential function in GDM clinical diagnosis and therapeutic approach. In this review, we summarized an integrated expressional profile and the pathophysiological significance of placental exosomes and associated miRNAs, as well as other plasma miRNAs such as exo-AT. Furthermore, we also discussed the practical application of exosomes in GDM postpartum outcomes and the potential function of several miRNAs as therapeutic target in the GDM pathological pathway, thus providing a novel clinical insight of these biological signatures into GDM therapeutic approach.

Non-Coding RNA: Role in Gestational Diabetes Pathophysiology and Complications

Gestational Diabetes Mellitus (GDM) is defined as glucose intolerance that develops in the second or third trimester of pregnancy. GDM can lead to short-term and long-term complications both in the mother and in the offspring. Diagnosing and treating this condition is therefore of great importance to avoid poor pregnancy outcomes. There is increasing interest in finding new markers with potential diagnostic, prognostic and therapeutic utility in GDM. Non-coding RNAs (ncRNAs), including microRNAs, long non-coding RNAs and circular RNAs, are critically involved in metabolic processes and their dysregulated expression has been reported in several pathological contexts. The aberrant expression of several circulating or placenta-related ncRNAs has been linked to insulin resistance and β-cell dysfunction, the key pathophysiological features of GDM. Furthermore, significant associations between altered ncRNA profiles and GDM-related complications, such as macrosomia or trophoblast dysfunction, have been observed. Remarkably, the deregulation of ncRNAs, which might be linked to a detrimental intrauterine environment, can lead to changes in the expression of target genes in the offspring, possibly contributing to the development of long-term GDM-related complications, such as metabolic and cardiovascular diseases. In this review, all the recent findings on ncRNAs and GDM are summarized, particularly focusing on the molecular aspects and the pathophysiological implications of this complex relationship.