Inhibition of p300 histone acetyltransferase activity in palate mesenchyme cells attenuates Wnt signaling via aberrant E-cadherin expression

Wnt/β-catenin signaling pathway in carcinogenesis and cancer therapy

The Wnt/β-catenin signaling pathway plays a crucial role in various physiological processes, encompassing development, tissue homeostasis, and cell proliferation. Under normal physiological conditions, the Wnt/β-catenin signaling pathway is meticulously regulated. However, aberrant activation of this pathway and downstream target genes can occur due to mutations in key components of the Wnt/β-catenin pathway, epigenetic modifications, and crosstalk with other signaling pathways. Consequently, these dysregulations contribute significantly to tumor initiation and progression. Therapies targeting the Wnt/β-catenin signaling transduction have exhibited promising prospects and potential for tumor treatment. An increasing number of medications targeting this pathway are continuously being developed and validated. This comprehensive review aims to summarize the latest advances in our understanding of the role played by the Wnt/β-catenin signaling pathway in carcinogenesis and targeted therapy, providing valuable insights into acknowledging current opportunities and challenges associated with targeting this signaling pathway in cancer research and treatment.

Osteogenic microenvironment affects palatal development through glycolysis

Palate development involves various events, including proliferation, osteogenic differentiation, and epithelial-mesenchymal transition. Disruption of these processes can result in the cleft palate (CP). Mouse embryonic palatal mesenchyme (MEPM) cells are commonly used to explore the mechanism of palatal development and CP. However, the role of the microenvironment in the biological properties of MEPM cells, which undergoes dynamic changes during palate development, is rarely reported. In this study, we investigated whether there were differences between the palatal shelf mesenchyme at different developmental stages. Our results found that the palatal shelves facilitate proliferation at the early palate stage at mouse embryonic day (E) 13.5 and the tendency towards osteogenesis at E15.5, the late palate development stage. And the osteogenic microenvironment, which was mimicked by osteogenic differentiation medium (OIM), affected the biological properties of MEPM cells when compared to the routine medium. Specifically, MEPM cells showed slower proliferation, shorter S phase, increased apoptosis, and less migration distance after osteogenesis. E15.5 MEPM cells were more sensitive than E13.5, showing an earlier change. Moreover, E13.5 MEPM cells had weaker osteogenic ability than E15.5, and both MEPM cells exhibited different Lactate dehydrogenase A (LDHA) and Cytochrome c (CytC) expressions in OIM compared to routine medium, suggesting that glycolysis might be associated with the influence of the osteogenic microenvironment on MEPM cells. By comparing the stemness of the two cells, we investigated that the stemness of E13.5 MEPM cells was stronger than that of E15.5 MEPM cells, and E15.5 MEPM cells were more like differentiated cells than stem cells, as their capacity to differentiate into multiple cell fates was reduced. E13.5 MEPM cells might be the precursor cells of E15.5 MEPM cells. Our results enriched the understanding of the effect of the microenvironment on the biological properties of E13.5 and E15.5 MEPM cells, which should be considered when using MEPM cells as a model for palatal studies in the future.

Rs28446116 in PTCH1 is associated with non-syndromic cleft lip with or without palate in the Ningxia population, China

OBJECTIVES

To investigate the association between PTCH1 single nucleotide polymorphism(SNP) and non-syndromic cleft lip with or without palate (NSCL/P) in the Ningxia Hui Autonomous region and predict the function of single nucleotide polymorphism through bioinformatics analysis.

DESIGN

A case-control analysis of 31 single nucleotide polymorphism locus alleles on PTCH1 gene (504 cases and 455 controls) was performed to explore the association between PTCH1 gene polymorphisms and non-syndromic cleft lip with or without palate in Ningxia region. Transcription factors, 3D single nucleotide polymorphism and other related information of single nucleotide polymorphism loci with statistical significance were screened by the case-control experiments, and then analyzed the corresponding transcription factors through the NCBI database.

RESULTS

The case-control study showed that 5 of the 31 single nucleotide polymorphism loci rs357564 (P = 0.0233), rs1805155 (P = 0.0371), rs28446116 (P = 0.0408), rs2282041 (P = 0.0439), rs56119276 (P = 0.0256) had statistically significant differences in allele frequencies between the case and control groups. Bioinformatics analysis revealed that EP300 and RUNX3, among the transcription factors associated with rs28446116, may be associated with the development of non-syndromic cleft lip with or without palate.

CONCLUSION

PTCH1 gene may be associated with the occurrence of non-syndromic cleft lip with or without palate in the Ningxia region, which may be related to the role of EP300 and RUNX3 in the development of cleft lip and palate.

Identification of histone malonylation in the human fetal brain and implications for diabetes-induced neural tube defects

BACKGROUND

Neural tube defects (NTDs) are severe congenital malformations. Diabetes during pregnancy is a risk factor for NTDs, but its mechanism remains elusive. Emerging evidence suggests that protein malonylation is involved in diabetes. Here, we report the correlation between histone lysine malonylation in diabetes-induced NTDs.

METHODS

Nano-HPLC/MS/MS was used to screen the histone malonylation profile in human embryonic brain tissue. Then, the histone malonylation level was compared between the brains of normal control mice and mice with diabetes-induced NTDs. Finally, the histone malonylation level was compared under high glucose exposure in an E9 neuroepithelial cell line (NE4C).

RESULTS

A total of 30 histone malonylation sites were identified in human embryonic brain tissue, including 18 novel sites. Furthermore, we found an increased histone malonylation level in brain tissues from mice with diabetes-induced NTDs. Finally, both the histone malonylation modified sites and the modified levels were proved to be increased in the NE4C treated with high glucose.

CONCLUSION

Our results present a comprehensive map of histone malonylation in the human fetal brain. Furthermore, we provide experimental evidence supporting a relationship between histone malonylation and NTDs caused by high glucose-induced diabetes. These findings offer new insights into the pathological role of histone modifications in human NTDs.

MIER3 suppresses the progression of non-small cell lung cancer by inhibiting Wnt/β-Catenin pathway and histone acetyltransferase activity

BACKGROUND

The mesoderm induction early response 1, family member 3 (MIER3) gene has been recognized as potentially being associated with cancer. However, in relation to the development of non-small cell lung cancer (NSCLC), the expression pattern and the role of MIER3 are yet to be reported. The aim of this research was to investigate the rate of expression of MIER3 in NSCLC cells and tissues and to investigate the role of MIER3 in NSCLC.

METHODS

Seventeen patients received NSCLC tissues and corresponding healthy tissues. MTT assay was used to determine cell proliferation. For detecting mRNA and protein expression, we used both quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot method. To measure cell apoptosis and cell cycle distribution, we applied the flow cytometry technique. We used a wound-healing assay and a Transwell invasion assay to study cell migration and invasion.

RESULTS

In comparison with adjacent normal tissues, the expression of MIER3 was down-regulated in NSCLC tissues. In addition, the level of MIER3 in NSCLC cell lines was also lower than in pulmonary epithelial cell BEAS-2B. Moreover, when MIER3 was overexpressed, cell proliferation, migration, and invasion were significantly inhibited, apoptosis increased, and cell cycle arrest was induced in A549 and H460 cells. MIER3 overexpression also suppressed tumor growth in NSCLC xenograft mouse models. Furthermore, our study demonstrated that MIER3 down-regulated the Wnt/β-catenin signaling pathway in NSCLC cells. More importantly, MIER3 decreased the activity of histone acetyltransferase (HAT) p300, which may have contributed to its regulation on β-catenin and tumorigenesis.

CONCLUSIONS

The data suggests MIER3 takes on the tumor-suppressor role in the progression of NSCLC and, therefore, could prove to be a valuable clinical marker in the prognosis of the disease.

PBX-WNT-P63-IRF6 pathway in nonsyndromic cleft lip and palate

Nonsyndromic cleft lip and palate (NSCLP) is one of the most common craniofacial anomalies in humans, affecting more than 135,000 newborns worldwide. NSCLP has a multifactorial etiology with more than 50 genes postulated to play an etiologic role. The genetic pathway comprised of Pbx-Wnt-p63-Irf6 genes was shown to control facial morphogenesis in mice and proposed as a regulatory pathway for NSCLP. Based on these findings, we investigated whether variation in PBX1, PBX2, and TP63, and their proposed interactions were associated with NSCLP. Fourteen single nucleotide variants (SNVs) in/nearby PBX1, PBX2, and TP63 were genotyped in 780 NSCLP families of nonHispanic white (NHW) and Hispanic ethnicities. Family-based association tests were performed for individual SNVs stratified by ethnicity and family history of NSCLP. Gene-gene interactions were also tested. A significant association was found for PBX2 rs3131300 and NSCLP in combined Hispanic families (p = .003) while nominal association was found for TP63 rs9332461 in multiplex Hispanic families (p = .005). Significant haplotype associations were observed for PBX2 in NHW (p = .0002) and Hispanic families (p = .003), and for TP63 in multiplex Hispanic families (.003). An independent case-control group was used to validate findings, and significant associations were found with PBX1 rs6426870 (p = .007) and TP63 rs9332461 (p = .03). Gene-gene interactions were detected between PBX1/PBX2/TP63 with IRF6 in NHW families, and between PBX1 with WNT9B in both NHW and Hispanic families (p < .0018). This study provides the first evidence for a role of PBX1 and PBX2, additional evidence for the role of TP63, and support for the proposed PBX-WNT-TP63-IRF6 regulatory pathway in the etiology of NSCLP.

Coenzyme A-aptamer-facilitated label-free electrochemical stripping strategy for sensitive detection of histone acetyltransferase activity

Abnormal histone acetyltransferases (HAT) activity gives rise to all kinds of cellular diseases. Herein, we first report a coenzyme A (CoA)-aptamer-facilitated label-free electrochemical stripping biosensor for sensitive detection of HAT activity via square wave voltammetry (SWV) technique. The presence of HAT can lead to the transfer of the acetyl group from acetyl coenzyme A (Ac-CoA) to lysine residues of substrate peptide, thus generating CoA molecule. Later, CoA, which acts as an initiator, can embrace its aptamer via the typical target-aptamer interaction, then arousing deoxynucleotide terminal transferase (TdT)-induced silver nanoclusters (AgNCs) as signal output. Under optimized conditions, the resultant aptasensor shows obvious electrochemical stripping signal and is employed for HAT p300 analysis in a wide concentration range from 0.01 to 100 nM with a very low detection limit of 0.0028 nM (3δ/slope). The good analytical performances of the biosensor depend on the strong interaction of CoA and its aptamer and abundant stripping resource rooted from AgNCs. Next, the proposed biosensor is used for screening HAT's inhibitors and the practical HAT detection with satisfactory results. Therefore, the new, simple and sensitive HAT biosensor presents a promising direction for HAT-targeted drug discovery and epigenetic research.

p300 mediates the histone acetylation of ORMDL3 to affect airway inflammation and remodeling in asthma

BACKGROUND

Bronchial asthma is affected by both environmental and genetic factors. The orosomucoid 1-like protein 3 (ORMDL3) gene is related to childhood asthma and is involved in airway inflammation and airway remodeling. The ORMDL3 promoter contains binding sites for the histone acetylase p300. Gene expression can be affected by epigenetic modifications. This study aimed to investigate whether the p300-mediated histone acetylation (HAT) of ORMDL3 gene affects airway inflammation and remodeling in asthma.

METHODS

16HBE14o- cells were transfected with various concentrations of a wild-type p300 plasmid or p300HAT-deletion plasmids. A dual luciferase reporter assay was used to examine the effect of p300-mediated HAT on the ORMDL3 promoter. Thirty BALB/c mice were randomly divided into a control group, an ovalbumin (OVA)-induced asthma group and an asthma + C646 (a selective inhibitor of p300) group. Noninvasive lung function tests were conducted to examine airway hyperreactivity (AHR) in the different groups. HE and Masson's trichrome staining was performed to examine airway remodeling and inflammation. Immunohistochemistry, western blotting and real-time PCR were used to analyze ORMDL3 expression in lung tissues. ELISA and western blotting were used to evaluate the HAT status in lung tissue. The ChIP assay was used to determine the relationship of the ORMDL3 promoter to p300 or acetylated histone H3 (aceH3).

RESULTS

p300 activated transcription from the ORMDL3 promoter, resulting in an increase in endogenous ORMDL3 mRNA levels. ORMDL3 promoter activity was reduced when the HAT activity of p300 was lost. ORMDL3 expression was elevated, and HAT activity was high in the lung tissues of asthmatic mice. p300 and aceH3 bound to the promoter region of ORMDL3. In the asthma group, the amounts of p300 and aceH3 recruited to the ORMDL3 promoter were increased. C646 inhibited p300 expression and reduced HAT activity and aceH3 levels in asthmatic mice, thereby reducing ORMDL3 expression and relieving AHR and airway remodeling.

CONCLUSION

p300-mediated HAT modulates the expression of the asthma susceptibility gene ORMDL3, thereby improving the process of airway inflammation and remodeling in asthma.

Decline of p300 contributes to cell senescence and growth inhibition of hUC-MSCs through p53/p21 signaling pathway

Human umbilical cord-derived mesenchymal stromal cells (hUC-MSCs) in vitro expansion for long term may undergo epigenetic and genetic alterations that subsequently induce cellular senescence and associated growth inhibition. Increasing evidence implicated that aberrant histone acetylation modulates gene expression responsible for MSCs aging. Whether the dysregulation of p300 and its KAT activity is involved in the aging process of MSCs was still unexplored. In this study, we found a significant decrease of p300 but elevated p53/p21 levels in senescent hUC-MSCs at late-passage. Then we used two different approaches: (i) downregulation of p300 by siRNA and (ii) inhibition of the acetyltransferase(KAT) activity by C646 to determine the role of p300 in regulating MSCs senescence. We showed that inhibition of p300 induce premature senescence and decrease proliferation potential in hUC-MSCs. Moreover, upregulations of p53 and p21 expressions were confirmed in p300 knockdown and C646-treated hUC-MSCs. Taken together, these results suggest that p300 plays an important role in aging process of MSCs associated with activation of p53/p21 signaling pathway.

Ultrasensitive mushroom-like electrochemical immunosensor for probing the activity of histone acetyltransferase

A novel mushroom-like electrochemical immunoassay for the ultrasensitive detection of histone acetyltransferase activity (HAT p300) has been established on account of the new composite graphene oxide (GO) nanolayer. The immunoassay involves immobilization of substrate peptide onto Au electrode, acetylation in lysine of substrate peptide, and the interaction between acetyl group of lysine and acetyl-antibody (Ab_Ac) of the GO nanolayer. The GO nanolayer comprises large amounts of methylene blue molecules (MB), giving rise to large signal amplification. Only in the presence of HAT p300, an obvious electrochemical signal appears and the peak linear current is proportion to the HAT p300 concentrations ranging from 0.01 to 150 nM with a detection limit of 0.0036 nM. The great enhancement on sensitivity of the proposed mushroom-like immunosensor derives from both the constructed Faraday cage and the extended outer Helmholtz plane (OHP). Further, the immunosensor with excellent sensitivity and selectivity can be applied for the HAT p300 activity detection in Hela cell lysates, serum and urine, hinting an improved and splendid analytical performance. Briefly, this stable, simple and ultrasensitive electrochemical immunoassay has considerable promise for further applications in the HATs-interrelated epigenetic studies and drug development.

Wnt signaling in orofacial clefts: crosstalk, pathogenesis and models

Diverse signaling cues and attendant proteins work together during organogenesis, including craniofacial development. Lip and palate formation starts as early as the fourth week of gestation in humans or embryonic day 9.5 in mice. Disruptions in these early events may cause serious consequences, such as orofacial clefts, mainly cleft lip and/or cleft palate. Morphogenetic Wnt signaling, along with other signaling pathways and transcription regulation mechanisms, plays crucial roles during embryonic development, yet the signaling mechanisms and interactions in lip and palate formation and fusion remain poorly understood. Various Wnt signaling and related genes have been associated with orofacial clefts. This Review discusses the role of Wnt signaling and its crosstalk with cell adhesion molecules, transcription factors, epigenetic regulators and other morphogenetic signaling pathways, including the Bmp, Fgf, Tgfβ, Shh and retinoic acid pathways, in orofacial clefts in humans and animal models, which may provide a better understanding of these disorders and could be applied towards prevention and treatments.

CBP/p300 inhibitor C646 prevents high glucose exposure induced neuroepithelial cell proliferation

BACKGROUND

Maternal diabetes related neural tube defects (NTDs) are a result of oxidative stress and apoptosis. However, the molecular mechanism behind the pathogenesis is not fully understood. Here, we report that high glucose exposure-induced epigenetic changes influence histone H4 acetylation and neuroepithelial cell proliferation. We also show that the acetyltransferase inhibitor C646 can prevent high glucose induced changes in histone H4 acetylation and neuroepithelial cell proliferation.

METHODS

By using LC-MS/MS as an unbiased approach, we screened the histone acetylation profile in an E9 neuroepithelial cell line (NE-4C) under high glucose exposure. We further explored the mechanism in cells in vitro and in maternal diabetes-induced mouse embryos in vivo.

RESULTS

We identified 35 core histone acetylation marks in normal E9 neuroepithelial cells, whereas high glucose exposure resulted in novel acetylation sites on H4K31 and H4K44. Acetylation levels of embryonic development associated H4K5/K8/K12/K16 increased in neuroepithelial cells exposed to high glucose in vitro and in brain tissue from maternal diabetes induced exencephalic embryos in vivo. Further, mRNA level of histone acetyltransferase CBP encoded gene Crebbp was significantly increased both in vitro and in vivo. The addition of C646, a selective inhibitor for CBP/p300, significantly rescued increase of H4K5/K8/K12/K16 acetylation levels and H3S10pi-labeled neuroepithelial cell proliferation induced by high glucose exposure.

CONCLUSION

Our data provide complementary insights for potential mechanisms of maternal diabetes induced NTDs.

Promoter methylation status of the tumor suppressor genes p16 and cadherin 1 in cervical intraepithelial neoplasia

Cervical cancer is the second most common female cancer worldwide. DNA methylation is one of a number of epigenetic regulation mechanisms leading to gene silencing in neoplastic cells. Aberrant methylation results in the silencing of tumor suppressor gene expression, and has been detected in a high percentage of human cancers. In the present study, the methylation status of three tumor suppressor genes, retinoic acid receptor β (RARβ), p16 and cadherin 1 (CDH1), and the inflammatory-associated cyclooxygenase-2 (COX-2) gene, was examined at distinct stages of cervical intraepithelial neoplasia (CIN). The results of the present study revealed that the COX-2 gene was unmethylated between CIN I and carcinoma specimens. The RARβ gene exhibited a minimal change in methylation frequency, whereas the CDH1 methylation level was increased <2-fold between CIN I and carcinoma. Notably, the methylation frequency of p16 was 13.2% in normal specimens; 18.2% in CIN I; 35.7% in CIN II; 31.6% in CIN III; and 15.4% in carcinoma. By contrast, the methylation frequency of p16 increased between CIN I and carcinoma in the absence of high-risk group papillomaviruses. The results of bisulfite sequencing indicated that the 10 CpG sites were all methylated in p16 gene methylation-positive individuals. The results of the present study demonstrate that the methylation frequency of p16 and CDH1 was progressively increased during the development of malignant stages in CIN, and may be an additional tool for current cytomorphology-based screening of cervical cell specimens.