Involvement of elevated ASF1B in the poor prognosis and tumorigenesis in pancreatic cancer

Transcriptomic analysis identified novel biomarker in invasive placenta accreta spectrum

INTRODUCTION

Placenta accreta spectrum (PAS) disorders pose a grave threat to maternal life due to severe hemorrhage and the heightened risk of peripartum hysterectomy. Consequently, there's a pressing need for circulating biomarkers in clinical settings. MicroRNAs (miRNAs), being stable in peripheral circulation, hold promise as potential biomarkers for PAS.

METHODS

This study recruited singleton live pregnancies, including cases of invasive PAS, placenta previa (PP), and controls, across three phases. Initially, RNA-seq of peripheral blood identified 6 miRNAs in the screening phase. Subsequently, in the training and validation phases, miR-23a-5p, along with its target genes ASF1B and CHTF8, were validated using qRT-PCR. The diagnostic value of these markers for PAS and adverse outcomes was evaluated using Receiver Operating Characteristic (ROC) curves.

RESULTS

The results showed miR-23a-5p was down-regulated in PAS, whereas ASF1B and CHTF8 were up-regulated. miR-23a-5p had modest diagnostic efficiency for PAS and adverse outcomes, as the AUC were 0.689 and 0.711 respectively. However, when miR-23a-5p combined with CHTF8, the AUC can improve greatly to 0.869 in PAS diagnosis and 0.856 in prediction of adverse outcomes.

DISCUSSION

We propose the miR-23a-5p plays a role in PAS pathogenesis through regulating cell proliferation, migration, invasion, apoptosis by targeting various genes. This study confirmed its potential value of miR-23a-5p combined with target gene CHTF8 as novel biomarkers for PAS and adverse outcomes.

ASF1B is an essential prognostic indicator linked to the growth and resistance characteristics of bladder cancer

BACKGROUND

Anti-silencing function 1 (ASF1) is a conserved histone H3-H4 chaperone protein. ASF1B (Anti-Silencing Function 1B Histone Chaperone), a paralog of ASF1, is involved in tumor metabolism and growth. The regulatory network of ASF1B in cancer is intricate and remains inadequately explored. The objective of this study was to examine the biological role of ASF1B in bladder cancer (BC).

METHODS

The presence of ASF1B in BC was examined using The Cancer Genome Atlas (TCGA) and Cancer Cell Line Encyclopedia (CCLE) databases. In addition, a correlation analysis was performed to evaluate the association between the BC pathway scores and ASF1B. ASF1B expression in BC cells was detected using western blott and RT-PCR. Several investigations were conducted, both within and outside of a living organism, to confirm the involvement of ASF1B in the regulation of biological processes in BC cells.

RESULTS

Our examination of the database indicates that ASF1B exhibits significant expression levels in BC cells and is potentially strongly associated with the growth of BC cells and the repair of DNA. The expression of ASF1B in BC cells was found to be significantly elevated, as indicated by the results of western blot and RT-PCR. The findings of the cell plate cloning test, edu analysis, flow cytometry, and transwell experiments demonstrated that the inhibition of ASF1B greatly impeded the proliferation and migration of BC cells. After establishing drug-resistant BC cell lines in a lab, suppressing ASF1B gene expression led to a notable reduction in BC cells' resistance to cisplatin. Confirmation was achieved by flow cytometry and western blott assays. Our in vivo findings demonstrated that the suppression of ASF1B resulted in an amelioration of the pathological condition, a decrease in resistance to cisplatin, and an inhibition of the growth of BC in mice.

Investigation on the molecular mechanism of SPA interference with osteogenic differentiation of bone marrow mesenchymal stem cells

Binding of Staphylococcus aureus protein A (SPA) to osteoblasts induces apoptosis and inhibits bone formation. Bone marrow-derived mesenchymal stem cells (BMSCs) have the ability to differentiate into bone, fat and cartilage. Therefore, it was important to analyze the molecular mechanism of SPA on osteogenic differentiation. We introduced transcript sequence data to screen out differentially expressed genes (DEGs) related to SPA-interfered BMSC. Protein-protein interaction (PPI) network of DEGs was established to screen biomarkers associated with SPA-interfered BMSC. Receiver operating characteristic (ROC) curve was plotted to evaluate the ability of biomarkers to discriminate between two groups of samples. Finally, we performed GSEA and regulatory analysis based on biomarkers. We identified 321 DEGs. Subsequently, 6 biomarkers (Cenpf, Kntc1, Nek2, Asf1b, Troap and Kif14) were identified by hubba algorithm in PPI. ROC analysis showed that six biomarkers could clearly discriminate between normal differentiated and SPA-interfered BMSC. Moreover, we found that these biomarkers were mainly enriched in the pyrimidine metabolism pathway. We also constructed '71 circRNAs-14 miRNAs-5 mRNAs' and '10 lncRNAs-5 miRNAs-2 mRNAs' networks. Kntc1 and Asf1b genes were associated with rno-miR-3571. Nek2 and Asf1b genes were associated with rno-miR-497-5p. Finally, we found significantly lower expression of six biomarkers in the SPA-interfered group compared to the normal group by RT-qPCR. Overall, we obtained 6 biomarkers (Cenpf, Kntc1, Nek2, Asf1b, Troap, and Kif14) related to SPA-interfered BMSC, which provided a theoretical basis to explore the key factors of SPA affecting osteogenic differentiation.

Activation of the FOXM1/ASF1B/PRDX3 axis confers hyperproliferative and antioxidative stress reactivity to gastric cancer

Nucleosome assembly during DNA replication is dependent on histone chaperones. Recent studies suggest that dysregulated histone chaperones contribute to cancer progression, including gastric cancer (GC). Further studies are required to explore the prognostic and therapeutic implications of histone chaperones and their mechanisms of action in GC progression. Here we identified histone chaperone ASF1B as a potential biomarker for GC proliferation and prognosis. ASF1B was significantly upregulated in GC, which was associated with poor prognosis. In vitro and in vivo experiments demonstrated that the inhibition of ASF1B suppressed the malignant characteristics of GC, while overexpression of ASF1B had the opposite effect. Mechanistically, transcription factor FOXM1 directly bound to the ASF1B-promoter region, thereby regulating its transcription. Treatment with thiostrepton, a FOXM1 inhibitor, not only suppressed ASF1B expression, but also inhibited GC progression. Furthermore, ASF1B regulated the mitochondrial protein peroxiredoxin 3 (PRDX3) transcription in a FOXM1-dependent manner. The crucial role of ASF1B-regulated PRDX3 in GC cell proliferation and oxidative stress balance was also elucidated. In summary, our study suggests that the FOXM1-ASF1B-PRDX3 axis is a potential therapeutic target for treating GC.

Structure-activity relationships for the G-quadruplex-targeting experimental drug QN-302 and two analogues probed with comparative transcriptome profiling and molecular modeling

The tetrasubstituted naphthalene diimide compound QN-302 binds to G-quadruplex (G4) DNA structures. It shows high potency in pancreatic ductal adenocarcinoma (PDAC) cells and inhibits the transcription of cancer-related genes in these cells and in PDAC animal models. It is currently in Phase 1a clinical evaluation as an anticancer drug. A study of structure-activity relationships of QN-302 and two related analogues (CM03 and SOP1247) is reported here. These have been probed using comparisons of transcriptional profiles from whole-genome RNA-seq analyses, together with molecular modelling and molecular dynamics simulations. Compounds CM03 and SOP1247 differ by the presence of a methoxy substituent in the latter: these two compounds have closely similar transcriptional profiles. Whereas QN-302 (with an additional benzyl-pyrrolidine group), although also showing down-regulatory effects in the same cancer-related pathways, has effects on distinct genes, for example in the hedgehog pathway. This distinctive pattern of genes affected by QN-302 is hypothesized to contribute to its superior potency compared to CM03 and SOP1247. Its enhanced ability to stabilize G4 structures has been attributed to its benzyl-pyrrolidine substituent fitting into and filling most of the space in a G4 groove compared to the hydrogen atom in CM03 or the methoxy group substituent in SOP1247.

CIA-II is associated with lower-grade glioma survival and cell proliferation

BACKGROUND

The role of CIA-II has been clarified in several types of tumors; however, whether dysregulated CIA-II expression is also involved in the pathophysiology of lower-grade glioma (LGG) remains undisclosed.

METHODS

A comprehensive pan-cancer analysis of the expression patterns and prognostic significance of CIA-II in miscellaneous tumors was undertaken. Subsequently, a detailed bioinformatics analysis was executed to identify putative correlations between CIA-II expression and clinical features, prognosis, biological functions, immunological characteristics, genomic alterations, and chemotherapeutics in LGG. In vitro studies were implemented to examine the potential roles of CIA-II in LGG.

RESULTS

CIA-II expression was found to be abnormally elevated in a variety of tumors, including LGG. Additionally, patients with LGG with higher CIA-II expression owned worse prognosis. Importantly, the results declared that CIA-II expression was an independent prognostic indicator for LGG. Moreover, the expression of CIA-II was tightly interrelated with immune cell infiltration, gene mutations, and chemotherapeutics in LGG. In vitro studies revealed that CIA-II was increased and strongly related to the cell proliferation in LGG.

CONCLUSION

CIA-II may be an independent prognostic factor and a serviceable therapeutic target in LGG.

ASF1B acted as a prognostic biomarker for stomach adenocarcinoma

Stomach adenocarcinoma (STAD) has a high mortality rate due to the lack of highly sensitive biomarkers. Therefore, the search for potential tumor markers is of great value. ASF1B is a prognostic marker for a variety of tumors, while the prognostic value and immune microenvironment of ASF1B in STAD remain unclear, and to be determined. Kaplan-Meier analysis was performed to analyze the prognostic role of ASF1B in STAD. Functional enrichment of ASF1B was explored with GO and KEGG pathway analysis. We also explored the correlation between ASF1B expression and immune infiltration in STAD. ASF1B was significantly upregulated in STAD tissues and high expression of ASF1B indicated a poor overall survival, progression-free survival, and first progression rate in STAD. The functional enrichment analysis of ASF1B and related genes showed high enrichment in the cell cycle and DNA repair, and the ASF1B high expression group was also mainly enriched in pathways such as the cell cycle. Analysis of tumor immune infiltration showed that ASF1B expression was significantly associated with the majority of immune cell infiltration in STAD. Moreover, STAD patients with high ASF1B expression had a higher tumor mutation burden score, microsatellite instability score, PD-1 immunophenoscore, and immune checkpoint expression. Our results suggest that ASF1B was an independent prognostic factor for STAD as well as a potential target for immunotherapy.

Anti‑silencing function 1B promotes the progression of pancreatic cancer by activating c‑Myc

The present study aimed to explore the role of histone chaperone anti‑silencing function 1B (ASF1B) in pancreatic cancer and the underlying mechanism. The biological function of ASF1B was investigated in pancreatic cancer cell lines (PANC‑1 and SW1990) and a mouse xenograft model. Chromatin immunoprecipitation was used to detect the effect of ASF1B on the transcriptional activity of c‑Myc. ASF1B was highly expressed in pancreatic adenocarcinoma (PAAD) samples from The Cancer Genome Atlas. ASF1B expression was positively associated with poor survival rates in patients with PAAD. Silencing of ASF1B in PANC‑1 and SW1990 cells inhibited cell proliferation, migration and invasion, and induced apoptosis. Mechanistically, ASF1B increased H3K56 acetylation (H3K56ac) in a CREB‑binding protein (CBP)‑dependent manner. ASF1B promoted H3K56ac at the c‑Myc promoter and increased c‑Myc expression. In PANC‑1 and SW1990 cells, the CBP inhibitor curcumin and the c‑Myc inhibitor 10058‑F4 reversed the promoting effects of ASF1B on cell proliferation, migration and invasion. In the mouse xenograft model, ASF1B silencing inhibited tumor growth, and was associated with low H3K56ac and c‑Myc expression. ASF1B promoted pancreatic cancer progression by activating c‑Myc via CBP‑mediated H3K56ac.

Anti-silencing function 1B knockdown suppresses the malignant phenotype of colorectal cancer by inactivating the phosphatidylinositol 3-kinase/AKT pathway

BACKGROUND

Mounting studies have highlighted the pivotal influence of anti-silencing function 1B (ASF1B) on the malignancy of cancers.

AIM

To explore the influence and mechanism of ASF1B in colorectal cancer (CRC).

METHODS

Quantitative real-time polymerase chain reaction (qRT-PCR) was used to detect mRNA expression of ASF1B. Immunohistochemical staining was performed to detect protein expression of ASF1B and Ki67 in tumor tissues. Western blot analysis was used to determine levels of ASF1B and proliferation/epithelial mesenchymal transition (EMT)/stemness-related proteins. In addition, the proliferation of CRC cells was assessed using Cell Counting Kit-8 and 5-Ethynyl-2’-Deoxyuridine assays. The migration and invasion of CRC cells were evaluated using transwell assays. Stemness of CRC cells was tested using the sphere formation assay. To construct a xenograft tumor model, HCT116 cells were introduced into mouse flanks via subcutaneous injection.

RESULTS

ASF1B expression was markedly increased in CRC tissues and cells, and it was inversely correlated with overall survival of CRC patients and was positively associated with the tumor node metastasis (TNM) stage of CRC patients. Silencing of ASF1B suppressed proliferation, migration, invasion, stemness and EMT of CRC cells as well as tumorigenesis of xenograft mice. Furthermore, protein levels of P-phosphatidylinositol 3-kinase (p-PI3K) and p-AKT were decreased after silencing of ASF1B in CRC cells. The inhibitory effects of ASF1B knockdown on cell proliferation, stemness and EMT were partly abolished by PI3K activator in CRC cells.

CONCLUSION

Silencing of ASF1B inactivated the PI3K/AKT pathway to suppress CRC malignancy in vitro.

Histone Chaperones and Digestive Cancer: A Review of the Literature

BACKGROUND

The global burden of digestive cancer is expected to increase. Therefore, crucial for the prognosis of patients with these tumors is to identify early diagnostic markers or novel therapeutic targets. There is accumulating evidence connecting histone chaperones to the pathogenesis of digestive cancer. Histone chaperones are now broadly defined as a class of proteins that bind histones and regulate nucleosome assembly. Recent studies have demonstrated that multiple histone chaperones are aberrantly expressed and have distinct roles in digestive cancers.

OBJECTIVE

The purpose of this review is to present the current evidence regarding the role of histone chaperones in digestive cancer, particularly their mechanism in the development and progression of esophageal, gastric, liver, pancreatic, and colorectal cancers. In addition, the prognostic significance of particular histone chaperones in patients with digestive cancer is discussed.

METHODS

According to PRISMA guidelines, we searched the PubMed, Embase, and MEDLINE databases to identify studies on histone chaperones and digestive cancer from inception until June 2022.

RESULTS

A total of 104 studies involving 21 histone chaperones were retrieved.

CONCLUSIONS

This review confirms the roles and mechanisms of selected histone chaperones in digestive cancer and suggests their significance as potential prognostic biomarkers and therapeutic targets. However, due to their non-specificity, more research on histone chaperones should be conducted in the future to elucidate novel strategies of histone chaperones for prognosis and treatment of digestive cancer.