RBBP4 promotes colon cancer malignant progression via regulating Wnt/β-catenin pathway

Interpreting the molecular mechanisms of RBBP4/7 and their roles in human diseases (Review)

Histone chaperones serve a pivotal role in maintaining human physiological processes. They interact with histones in a stable manner, ensuring the accurate and efficient execution of DNA replication, repair and transcription. Retinoblastoma binding protein (RBBP)4 and RBBP7 represent a crucial pair of histone chaperones, which not only govern the molecular behavior of histones H3 and H4, but also participate in the functions of several protein complexes, such as polycomb repressive complex 2 and nucleosome remodeling and deacetylase, thereby regulating the cell cycle, histone modifications, DNA damage and cell fate. A strong association has been indicated between RBBP4/7 and some major human diseases, such as cancer, age‑related memory loss and infectious diseases. The present review assesses the molecular mechanisms of RBBP4/7 in regulating cellular biological processes, and focuses on the variations in RBBP4/7 expression and their potential mechanisms in various human diseases, thus providing new insights for their diagnosis and treatment.

Aldehyde oxidase 1 promotes gallbladder carcinogenesis through ROS-mediated activation of the Wnt/β-catenin pathway

BACKGROUND

Aldehyde oxidase 1 (AOX1) is associated with various pathophysiological processes, including cancer. Specifically, AOX1 has been demonstrated to have a close relationship with the progression of certain cancers. However, the expression, function, and mechanisms of action of AOX1 in gallbladder cancer (GBC) remain unclear.

METHODS

Utilizing immunohistochemistry, the study quantified the prevalence of AOX1 within tissues of gallbladder carcinoma and those of the surrounding non-cancerous regions. In vitro assays using gallbladder carcinoma cell lines with modulated AOX1 expression levels were performed to assess the protein's role in cell proliferation, migration, and invasion. Furthermore, flow cytometry techniques were harnessed to determine the influence of AOX1 on the content of reactive oxygen species (ROS) in these cells. Additionally, the expression of epithelial-mesenchymal transition (EMT) markers and the Wnt/β-catenin signaling pathway markersin cells with varied AOX1 expression, detected through Western blot analyses. An in vivo xenograft model involving athymic mice was implemented to explore the influence of AOX1 on gallbladder tumor growth, with Western blot analysis applied to measure EMT marker expression in the resulting tumours.

RESULTS

Elevated AOX1 protein levels have been observed in gallbladder carcinoma tissues, with such upregulation linked to a negative prognostic outlook for patients. In vitro analyses demonstrate that enhanced AOX1 expression facilitates gallbladder carcinoma cell proliferation, migration, and invasion, while AOX1 suppression yields an inhibitory effect on these cellular behaviors. Western blot results reveal an inverse relationship between AOX1 and E-cadherin levels, yet was positively correlation with N-cadherin, Vimentin, and Snail within both gallbladder cancer cells and in vivo xenograft tumours. Further mechanistic investigation indicates that AOX1 elevation augments reactive oxygen species (ROS) production and initiates the Wnt/β-catenin signaling pathway in these cells. The application of N-acetylcysteine (NAC) and/or KY1797K attenuates the proliferative, migratory, and invasive enhancements imparted by AOX1 overexpression and reinforces these effects when AOX1 is silenced-achieved through ROS mitigation and the obstruction of the Wnt/β-catenin pathway. In vivo studies corroborate these findings, showing AOX1 overexpression to amplify xenograft tumor growth and mesenchymal marker expression, whereas AOX1 interference did the opposite.

CONCLUSIONS

The study indicates that AOX1 functions as a carcinogenic factor in gallbladder carcinoma, enhancing cell proliferation, migration, invasion, and the EMT. These effects are driven by the activation of the Wnt/β-catenin pathway mediated by reactive oxygen species (ROS). Therefore,AOX1 presents potential as a valuable prognostic and diagnostic marker as well as a target for therapeutic intervention in the gallbladder cancer.

Changes Induced by P2X7 Receptor Stimulation of Human Glioblastoma Stem Cells in the Proteome of Extracellular Vesicles Isolated from Their Secretome

Extracellular vesicles (EVs) are secreted from many tumors, including glioblastoma multiforme (GBM), the most common and lethal brain tumor in adults, which shows high resistance to current therapies and poor patient prognosis. Given the high relevance of the information provided by cancer cell secretome, we performed a proteomic analysis of microvesicles (MVs) and exosomes (EXOs) released from GBM-derived stem cells (GSCs). The latter, obtained from the brain of GBM patients, expressed P2X7 receptors (P2X7Rs), which positively correlate with GBM growth and invasiveness. P2X7R stimulation of GSCs caused significant changes in the EV content, mostly ex novo inducing or upregulating the expression of proteins related to cytoskeleton reorganization, cell motility/spreading, energy supply, protection against oxidative stress, chromatin remodeling, and transcriptional regulation. Most of the induced/upregulated proteins have already been identified as GBM diagnostic/prognostic factors, while others have only been reported in peripheral tumors. Our findings indicate that P2X7R stimulation enhances the transport and, therefore, possible intercellular exchange of GBM aggressiveness-increasing proteins by GSC-derived EVs. Thus, P2X7Rs could be considered a new druggable target of human GBM, although these data need to be confirmed in larger experimental sets.

Ropivacaine inhibits the malignant behavior of lung cancer cells by regulating retinoblastoma-binding protein 4

Background

Ropivacaine is a local anesthetic commonly used in regional nerve blocks to manage perioperative pain during lung cancer surgery. Recently, the antitumor potential of ropivacaine has received considerable attention. Our previous study showed that ropivacaine treatment inhibits the malignant behavior of lung cancer cells in vitro. However, the potential targets of ropivacaine in lung cancer cells have not yet been fully identified. This study aimed to explore the antitumor effects and mechanisms of action of ropivacaine in lung cancer.

Methods

Lung cancer A549 cells were treated with or without 1 mM ropivacaine for 48 h. Quantitative proteomics was performed to identify the differentially expressed proteins (DEPs) triggered by ropivacaine treatment. STRING and Cytoscape were used to construct protein-protein interaction (PPI) networks and analyze the most significant hub genes. Overexpression plasmids and small interfering RNA were used to modulate the expression of key DEPs in A549 and H1299 cells. MTS, transwell assays, and flow cytometry were performed to determine whether the key DEPs were closely related to the anticancer effect of ropivacaine on the malignant behavior of A549 and H1299 cells.

Results

Quantitative proteomic analysis identified 327 DEPs (185 upregulated and 142 downregulated proteins) following ropivacaine treatment. Retinoblastoma-binding protein 4 (RBBP4) was one of the downregulated DEPs and was selected as the hub protein. TCGA database showed that RBBP4 was significantly upregulated in lung cancer and was associated with poor patient prognosis. Inhibition of RBBP4 by siRNA resulted in a significant decrease in the proliferation and invasive capacity of lung cancer cells and the induction of cell cycle arrest. Additionally, the results indicated RBBP4 knockdown enhanced antitumor effect of ropivacaine on A549 and H1299 cells. Conversely, the overexpression of RBBP4 using plasmids reversed the inhibitory effects of ropivacaine.

Conclusion

Our data suggest that ropivacaine suppresses lung cancer cell malignancy by downregulating RBBP4 protein expression, which may help clarify the mechanisms underlying the antitumor effects of ropivacaine.

Unveiling the molecular structure and role of RBBP4/7: implications for epigenetic regulation and cancer research

Retinoblastoma-binding protein (RBBP) family is a class of proteins that can interact with tumor suppressor retinoblastoma protein (pRb). RBBP4 and RBBP7 are the only pair of homologous proteins in this family, serving as scaffold proteins whose main function is to offer a platform to indirectly connect two proteins. This characteristic allows them to extensively participate in the binding of various proteins and epigenetic complexes, indirectly influencing the function of effector proteins. As a result, they are often highlighted in organism activities involving active epigenetic modifications, such as embryonic development and cancer activation. In this review, we summarize the structural characteristics of RBBP4/7, the complexes they are involved in, their roles in embryonic development and cancer, as well as potential future research directions, which we hope to inspire the field of epigenetic research in the future.

Lead exposure induces neuronal apoptosis via NFκB p65/RBBP4/Survivin signaling pathway

Lead (Pb), as a heavy metal that is easily exposed in daily life, can cause damage to various systems of body. Apoptosis is an autonomous cell death process regulated by genes in order to maintain the stability of internal environment, which plays an important role in the development of nervous system. RB binding protein 4 (RBBP4) is one of the core histone binding subunits and is closely related to the apoptosis process of nervous system cells. However, it is not known whether RBBP4 can regulate neuronal apoptosis in lead-exposed environments. We exposed PC12 cells to 0 μM (control group), 1 μM, and 100 μM PbAc for 24 h to obtain cell samples. The female rats ingested drinking water containing 0, 0.5 g/L, and 2.0 g/L PbAc from the first day of pregnancy to three weeks after delivery to obtain hippocampal tissue samples from mammary rats. The results of TUNEL showed that lead exposure promoted the onset of apoptosis in cells and hippocampus. The mRNA and protein levels of the apoptosis-related protein Survivin were significantly reduced in the lead-exposed group compared to the control group. In addition, we found that lead exposure reduces the mRNA and protein levels of RBBP4 in PC12 cells and hippocampus, and increases the mRNA and protein levels of NFκB p65. Moreover, inhibiting NFκB p65 can reverse the decrease in RBBP4 expression in the lead exposure model. Overexpression of RBBP4 increased Survivin expression and reduced apoptosis induced by lead exposure. This suggests that lead exposure induces apoptosis through the NFκB p65/RBBP4/Survivin signaling pathway.

Two-Dimensional Polyacrylamide Gel Electrophoresis Coupled with Nanoliquid Chromatography-Tandem Mass Spectrometry-Based Identification of Differentially Expressed Proteins and Tumorigenic Pathways in the MCF7 Breast Cancer Cell Line Transfected for Jumping Translocation Breakpoint Protein Overexpression

The identification of new genes/proteins involved in breast cancer (BC) occurrence is widely used to discover novel biomarkers and understand the molecular mechanisms of BC initiation and progression. The jumping translocation breakpoint (JTB) gene may act both as a tumor suppressor or oncogene in various types of tumors, including BC. Thus, the JTB protein could have the potential to be used as a biomarker in BC, but its neoplastic mechanisms still remain unknown or controversial. We previously analyzed the interacting partners of JTBhigh protein extracted from transfected MCF7 BC cell line using SDS-PAGE complemented with in-solution digestion, respectively. The previous results suggested the JTB contributed to the development of a more aggressive phenotype and behavior for the MCF7 BC cell line through synergistic upregulation of epithelial-mesenchymal transition (EMT), mitotic spindle, and fatty acid metabolism-related pathways. In this work, we aim to complement the previously reported JTB proteomics-based experiments by investigating differentially expressed proteins (DEPs) and tumorigenic pathways associated with JTB overexpression using two-dimensional polyacrylamide gel electrophoresis (2D-PAGE). Statistically different gel spots were picked for protein digestion, followed by nanoliquid chromatography-tandem mass spectrometry (nLC-MS/MS) analysis. We identified six DEPs related to the JTBhigh condition vs. control that emphasize a pro-tumorigenic (PT) role. Twenty-one proteins, which are known to be usually overexpressed in cancer cells, emphasize an anti-tumorigenic (AT) role when low expression occurs. According to our previous results, proteins that have a PT role are mainly involved in the activation of the EMT process. Interestingly, JTB overexpression has been correlated here with a plethora of significant upregulated and downregulated proteins that sustain JTB tumor suppressive functions. Our present and previous results sustain the necessity of the complementary use of different proteomics-based methods (SDS-PAGE, 2D-PAGE, and in-solution digestion) followed by tandem mass spectrometry to avoid their limitations, with each method leading to the delineation of specific clusters of DEPs that may be merged for a better understanding of molecular pathways and neoplastic mechanisms related to the JTB's role in BC initiation and progression.

Expression and clinical significance of RBBP4 gene in lower-grade glioma: An integrative analysis

This study investigated the expression pattern of retinoblastoma binding protein 4 (RBBP4) gene in glioma and explored its associations with clinicopathologic characteristics and prognosis of patients. Data retrieved from the GEPIA, CGGA, HPA and TIMER databases were processed to analyze RBBP4 expression in glioma and investigate its relationship with clinicopathologic characteristics, tumor immune infiltration and prognosis in glioma patients. Immunohistochemistry was applied to determine the expression of RBBP4 protein in glioma tissue. Additionally, the Coexpedia database was visited to identify co-expressed genes for RBBP4 gene, while the Cytoscape software was run to visualize the enriched GO entries and KEGG pathways of these co-expressed genes. The expression levels of RBBP4 in lower-grade glioma (LGG) and glioblastoma (GBM) tissues were markedly elevated when compared to normal tissues (both p < 0.05). The up-regulation of RBBP4 expression was associated with an increase in WHO grade (II-IV), wild-type IDH, and 1p/19q non-codeletion (all p < 0.05). Multi-variate Cox regression analysis showed that both increased abundance of infiltrating macrophages and up-regulated RBBP4 expression independently predicted poor survival outcomes in LGG patients (both p < 0.05). Furthermore, RBBP4 expression exhibited significant positive correlations with the abundance of infiltrating B cell, CD8+ T cell, CD4+ T cell, macrophage, neutrophil, and dendritic cell in LGG (all p < 0.05). Functional enrichment analyses indicated that the co-expressed genes associated with RBBP4 were highly involved in pathways such as the p53 signaling pathway, cell cycle, DNA replication, glutathione metabolism, as well as biological processes including cell cycle process, DNA replication, and DNA repair. High levels of RBBP4 are predictive for the poor survival outcome of LGG patients. RBBP4 gene, therefore, is expected to be a potential biomarker for prognosis of LGG and a target for immunotherapy.

HIF-1-Induced hsa-miR-429: Understanding Its Direct Targets as the Key to Developing Cancer Diagnostics and Therapies

MicroRNAs (miRNAs) play a critical role in the regulation of mRNA stability and translation. In spite of our present knowledge on the mechanisms of mRNA regulation by miRNAs, the utilization and translation of these ncRNAs into clinical applications have been problematic. Using hsa-miR-429 as an example, we discuss the limitations encountered in the development of efficient miRNA-related therapies and diagnostic approaches. The miR-200 family members, which include hsa-miR-429, have been shown to be dysregulated in different types of cancer. Although these miR-200 family members have been shown to function in suppressing epithelial-to-mesenchymal transition, tumor metastasis, and chemoresistance, the experimental results have often been contradictory. These complications involve not only the complex networks involving these noncoding RNAs, but also the problem of identifying false positives. To overcome these limitations, a more comprehensive research strategy is needed to increase our understanding of the mechanisms underlying their biological role in mRNA regulation. Here, we provide a literature analysis of the verified hsa-miR-429 targets in various human research models. A meta-analysis of this work is presented to provide better insights into the role of hsa-miR-429 in cancer diagnosis and any potential therapeutic approach.

RBBP4 regulates the expression of the Mre11-Rad50-NBS1 (MRN) complex and promotes DNA double-strand break repair to mediate glioblastoma chemoradiotherapy resistance

For treatment of glioblastoma (GBM), temozolomide (TMZ) and radiotherapy (RT) exert antitumor effects by inducing DNA double-strand breaks (DSBs), mainly via futile DNA mismatch repair (MMR) and inducing apoptosis. Here, we provide evidence that RBBP4 modulates glioblastoma resistance to chemotherapy and radiotherapy by recruiting transcription factors and epigenetic regulators that bind to their promoters to regulate the expression of the Mre11-Rad50-NBS1(MRN) complex and the level of DNA-DSB repair, which are closely associated with recovery from TMZ- and radiotherapy-induced DNA damage in U87MG and LN229 glioblastoma cells, which have negative MGMT expression. Disruption of RBBP4 induced GBM cell DNA damage and apoptosis in response to TMZ and radiotherapy and enhanced radiotherapy and chemotherapy sensitivity by the independent pathway of MGMT. These results displayed a possible chemo-radioresistant mechanism in MGMT negative GBM. In addition, the RBBP4-MRN complex regulation axis may provide an interesting target for developing therapy-sensitizing strategies for GBM.

CircAGO2 promotes colorectal cancer progression by inhibiting heat shock protein family B (small) member 8 via miR-1-3p/retinoblastoma binding protein 4 axis

This paper was to uncover the mechanism of circular RNA Argonaute 2 (circAGO2) in colorectal cancer (CRC) progression. The expression of circAGO2 was detected in CRC cells and tissues, and the relationship between clinicopathological features of CRC and circAGO2 level was evaluated. The growth and invasion of CRC cells and subcutaneous xenograft of nude mice were measured to evaluate the effect of circAGO2 on CRC development. Bioinformatics databases were applied to analyze levels of retinoblastoma binding protein 4 (RBBP4) and heat shock protein family B 8 (HSPB8) in cancer tissues. The relevance of circAGO2 and RBBP4 expression and the relationship between RBBP4 and HSPB8 during histone acetylation were assessed. The targeting relationship between miR-1-3p and circAGO2 or RBBP4 was predicted and confirmed. The effects of miR-1-3p and RBBP4 on biological functions of CRC cells were also verified. CircAGO2 was upregulated in CRC. CircAGO2 promoted the growth and invasion of CRC cells. CircAGO2 competitively bound to miR-1-3p and regulated RBBP4 expression, thus inhibiting HSPB8 transcription by promoting histone deacetylation. Silencing circAGO2 enhanced miR-1-3p expression and reduced RBBP4 expression, while suppression of miR-1-3p downgraded levels of miR-1-3p, up-regulated RBBP4, and facilitated cell proliferation and invasion in the presence of silencing circAGO2. RBBP4 silencing decreased RBBP4 expression and reduced proliferation and invasion of cells where circAGO2 and miR-1-3p were silenced. CircAGO2 overexpression decoyed miR-1-3p to increase RBBP4 expression, which inhibited HSPB8 transcription via histone deacetylation in HSPB8 promoter region, promoting proliferation and invasion of CRC cells.

Integrated analysis of necroptosis-related genes for evaluating immune infiltration and colon cancer prognosis

Background

Colon cancer (CC) is the second most common gastrointestinal malignancy. About one in five patients have already developed distant metastases at the time of initial diagnosis, and up to half of patients develop distant metastases from initial local disease, which leads to a poor prognosis for CC patients. Necroptosis plays a key role in promoting tumor growth in different tumors. The purpose of this study was to construct a prognostic model composed of necroptosis-related genes (NRGs) in CC.

Methods

The Cancer Genome Atlas was used to obtain information on clinical features and gene expression. Gene expression differential analysis, weighted gene co-expression network analysis, univariate Cox regression analysis and the least absolute shrinkage and selection operator regression algorithm were utilized to identify prognostic NRGs. Thereafter, a risk scoring model was established based on the NRGs. Biological processes and pathways were identified by gene ontology and gene set enrichment analysis (GSEA). Further, protein-protein interaction and ceRNA networks were constructed based on mRNA-miRNA-lncRNA. Finally, the effect of necroptosis related risk score on different degrees of immune cell infiltration was evaluated.

Results

CALB1, CHST13, and SLC4A4 were identified as NRGs of prognostic significance and were used to establish a risk scoring model. The time-dependent receiver operating characteristic curve analysis revealed that the model could well predict the 1-, 3-, and 5-year overall survival (OS). Further, GSEA suggested that the NRGs may participate in biological processes, such as the WNT pathway and JAK-Stat pathway. Eight key hub genes were identified, and a ceRNA regulatory network, which comprised 1 lncRNA, 5 miRNAs and 3 mRNAs, was constructed. Immune infiltration analysis revealed that the low-risk group had significantly higher immune-related scores than the high-risk group. A nomogram of the model was constructed based on the risk score, necroptosis, and the clinicopathological features (age and TNM stage). The calibration curves implied that the model was effective at predicting the 1-, 3-, and 5-year OS of CC.

Conclusion

Our NRG-based prognostic model can assist in the evaluation of CC prognosis and the identification of therapeutic targets for CC.

Molecular Characterization and Clinical Relevance of N6-Methyladenosine Regulators in Metastatic Prostate Cancer

Prostate cancer is a leading malignancy in the male population globally. N6-methylation of adenosine (m6A) is the most prevalent mRNA modification and plays an essential role in various biological processes in vivo. However, the potential roles of m6A in metastatic prostate cancer are largely unknown. In this study, we evaluated and identified two m6A modification patterns based on 21 m6A regulators in four public metastatic prostate cancer datasets. Different modification patterns correlated with distinct molecular characteristics. According to m6A-associated genes, we constructed a prognostic model, called m6Ascore, to predict the outcomes of patients with metastatic prostate cancer. We found that high m6A score level was related to dismal prognosis and characterized by higher cell cycle, DNA repair and mismatch repair pathway score. In vitro experiments confirmed that upregulation of METTL14, an m6A writer, enhanced the invasion, metastasis, and sensitivity of prostate cancer cells to poly (ADP-ribose) polymerase inhibitor. Conversely, down-regulation of potential target genes of m6A had the opposite effect. Finally, we validated that a higher m6A score was associated with a worse prognosis and a higher Gleason score in The Cancer Genome Atlas Program (TCGA) cohort. This work illustrated the nonnegligible role of m6A modification in multiple biological processes of metastatic prostate cancer. Evaluating the m6A risk scores of individual tumours will guide more effective judgement of prognosis as well as treatments for metastatic prostate cancer in clinical practice.

RBBP4 plays a vital role in the malignant progression of triple-negative breast cancer by regulating epithelial-mesenchymal transition

BACKGROUND

Mounting findings have revealed the increasingly appreciated functional importance of Retinoblastoma binding protein (RBBP) family members in tumorigenesis. However, the biological function of RBBP4 in breast cancer, especially in the most malignant and aggressive subtype, i.e., triple-negative breast cancer (TNBC), remains to be elucidated.

OBJECTIVE

The present study was aimed at elucidating the role of RBBP4 in TNBC pathogenesis.

METHODS

The expression of RBBP4 in TNBC tissues and cell lines was examined and its oncogenic-related functions were verified by performing a series of in vitro and in vivo experiments.

RESULTS

At the cellular and tissue level, a marked increase in the RBBP4 expression was observed. Functionally, RBBP4 knockdown dramatically inhibited the proliferation, invasion, and migration of TNBC cells in vitro. Further, mechanistically, RBBP4 downregulation regulated the inactivation of epithelial-mesenchymal transition (EMT) of TNBC cells. In vivo xenograft model in nude mice also validated these results.

CONCLUSION

Collectively, our results showed that the inhibition of RBBP4 suppresses the malignant progression of TNBC cells by regulating EMT. Thus, RBBP4 could serve as a novel biomarker and target for TNBC diagnosis and treatment.

Photoaffinity labeling-based chemoproteomic strategy reveals RBBP4 as a cellular target of protopanaxadiol against colorectal cancer cells

ABSTRCT Protopanaxadiol (PPD), a main ginseng metabolite, exerts powerful anticancer effects against multiple types of cancer; however, its cellular targets remain elusive. Here, we synthesized a cell-permeable PPD probe via introducing a bifunctional alkyne-containing diazirine photo-crosslinker and performed a photoaffinity labeling-based chemoproteomic study. We identified retinoblastoma binding protein 4 (RBBP4), a chromatin remodeling factor, as an essential cellular target of PPD in HCT116 colorectal cancer cells. PPD significantly decreased RBBP4-dependent trimethylation at lysine 27 of histone H3 (H3K27me3), a crucial epigenetic marker that correlates with histologic signs of colorectal cancer aggressiveness, and PPD inhibition of proliferation and migration of HCT116 cells was antagonized by RBBP4 RNA silencing. Collectively, our study highlights a previously undisclosed anti-colorectal cancer cellular target of the ginseng metabolite and advances the fundamental understanding of RBBP4 functions via a chemical biology strategy.

β-catenin correlates with the progression of colon cancers and berberine inhibits the proliferation of colon cancer cells by regulating the β-catenin signaling pathway

INTRODUCTION

Berberine was one of the active components in Chinese herb and exerted tumor suppressive role in cancer progression, but the exact antitumor mechanism is still not clearly clarified. In the present study, bioinformatics analysis was performed on COAD patients from TCGA, HPA database, UALCAN and GEPIA 2 platform. We also explored the role of berberine on progression of human colon cancers in vitro and in vivo and clarified weather the antitumor effects of berberine was mediated by Wnt/beta-catenin pathway.

METHODS

Cell viability was determined by MTT assay. The protein levels were tested by western blotting and the distribution of β-catenin was observed by confocal microscope.

RESULTS

The results showed the levels of CTNNB1 mRNA was increased in colon cancer patients than normal controls. The diagnostic value of CTNNB1 was AUC = 0.882 (CI:0.854-0.911) with sensitivity of 1.000 and specificity of 0.777. The promoter methylation level of CTNNB1 in COAD patients was significantly decreased. Moreover, univariate analysis and multivariate analysis results showed the expression of CTNNB1 in COAD patients was associated with T stage (p = 0.010), pathological stage (p = 0.025) and perineural invasion (p = 0.025). Furthermore, the in vitro assay results showed β-catenin signaling was highly activated in human colon cancer cells and berberine inhibited the cell viability of colon cancer cells in vitro and in vivo in a dose-and time-dependent manner. Moreover, berberine induced the translocation of β-catenin to cytoplasm from nucleus.

CONCLUSION

The levels of CTNNB1 mRNA was increased in colon cancer patients than normal controls. Berberine inhibited the proliferation of colon cancer cells by regulating the beta-catenin signaling pathway.

Global Proteomic Analysis of Mesenchymal Stem Cells Derived from Human Embryonic Stem Cells via Connective Tissue Growth Factor Treatment under Chemically Defined Feeder-Free Culture Conditions

Stem cells can be applied usefully in basic research and clinical field due to their differentiation and self-renewal capacity. The aim of this study was to establish an effective novel therapeutic cellular source and create its molecular expression profile map to elucidate the possible therapeutic mechanism and signaling pathway. We successfully obtained a mesenchymal stem cell population from human embryonic stem cells (hESCs) cultured on chemically defined feeder-free conditions and treated with connective tissue growth factor (CTGF) and performed the expressive proteomic approach to elucidate the molecular basis. We further selected 12 differentially expressed proteins in CTGF-induced hESC-derived mesenchymal stem cells (C-hESC-MSCs), which were found to be involved in the metabolic process, immune response, cell signaling, and cell proliferation, as compared to bone marrow derived-MSCs(BM-MSCs). Moreover, these up-regulated proteins were potentially related to the Wnt/β-catenin pathway. These results suggest that C-hESC-MSCs are a highly proliferative cell population, which can interact with the Wnt/β-catenin signaling pathway; thus, due to the upregulated cell survival ability or downregulated apoptosis effects of C-hESC-MSCs, these can be used as an unlimited cellular source in the cell therapy field for a higher therapeutic potential. Overall, the study provided valuable insights into the molecular functioning of hESC derivatives as a valuable cellular source.

Challenging, Accurate and Feasible: CAF-1 as a Tumour Proliferation Marker of Diagnostic and Prognostic Value

Simple Summary

There is an emerging need for new weapons in the battle against cancer; therefore, the discovery of new biomarkers with diagnostic, prognostic, and therapeutic value is a priority of current cancer research. An important task is to identify how quickly a tumour proliferates. A tumour’s proliferation rate is critical for grading and clinical decision-making; hence, there is an imperative need for accurate proliferation markers. Here, we review evidence demonstrating that chromatin assembly factor 1 (CAF-1) is a proliferation marker of clinical value. CAF-1 is selectively expressed in proliferating cells and its expression can be evaluated by immunohistochemistry in cytology smears and biopsies. CAF-1 expression is increased in almost all cancers and correlates strongly with the expression of Ki-67, the current routine proliferation marker. Overexpression of CAF-1 is associated with poor clinical outcome (advanced cancer stage, recurrence, metastasis, and decreased survival). CAF-1 is a robust, reproducible, and feasible proliferation marker of prognostic importance and may represent an attractive alternative or complementary to Ki-67 for cancer stratification and clinical guidance.

Abstract

The discovery of novel biomarkers of diagnostic, prognostic, and therapeutic value is a major challenge of current cancer research. The assessment of tumour cell proliferative capacity is pivotal for grading and clinical decision-making, highlighting the importance of proliferation markers as diagnostic and prognostic tools. Currently, the immunohistochemical analysis of Ki-67 expression levels is routinely used in clinical settings to assess tumour proliferation. Inasmuch as the function of Ki-67 is not fully understood and its evaluation lacks standardization, there is interest in chromatin regulator proteins as alternative proliferation markers of clinical value. Here, we review recent evidence demonstrating that chromatin assembly factor 1 (CAF-1), a histone chaperone selectively expressed in cycling cells, is a proliferation marker of clinical value. CAF-1 expression, when evaluated by immunocytochemistry in breast cancer cytology smears and immunohistochemistry in cancer biopsies from several tissues, strongly correlates with the expression of Ki-67 and other proliferation markers. Notably, CAF-1 expression is upregulated in almost all cancers, and CAF-1 overexpression is significantly associated, in most cancer types, with high histological tumour grade, advanced stage, recurrence, metastasis, and decreased patient survival. These findings suggest that CAF-1 is a robust, reproducible, and feasible proliferation marker of prognostic importance. CAF-1 may represent an attractive alternative or complementary to Ki-67 for cancer stratification and clinical guidance.