X-radiation inhibits histone deacetylase 1 and 2, upregulates Axin expression and induces apoptosis in non-small cell lung cancer

The scaffold protein AXIN1: gene ontology, signal network, and physiological function

AXIN1, has been initially identified as a prominent antagonist within the WNT/β-catenin signaling pathway, and subsequently unveiled its integral involvement across a diverse spectrum of signaling cascades. These encompass the WNT/β-catenin, Hippo, TGFβ, AMPK, mTOR, MAPK, and antioxidant signaling pathways. The versatile engagement of AXIN1 underscores its pivotal role in the modulation of developmental biological signaling, maintenance of metabolic homeostasis, and coordination of cellular stress responses. The multifaceted functionalities of AXIN1 render it as a compelling candidate for targeted intervention in the realms of degenerative pathologies, systemic metabolic disorders, cancer therapeutics, and anti-aging strategies. This review provides an intricate exploration of the mechanisms governing mammalian AXIN1 gene expression and protein turnover since its initial discovery, while also elucidating its significance in the regulation of signaling pathways, tissue development, and carcinogenesis. Furthermore, we have introduced the innovative concept of the AXIN1-Associated Phosphokinase Complex (AAPC), where the scaffold protein AXIN1 assumes a pivotal role in orchestrating site-specific phosphorylation modifications through interactions with various phosphokinases and their respective substrates.

Mechanism of METTL14-mediated m6A modification in non-small cell lung cancer cell resistance to cisplatin

Methyltransferase-like 14 (METTL14) mediates N⁶-methyladenosine (m⁶A) modification to influence cancer progression. This study aims to determine the mechanism of METTL14-mediated m⁶A in non-small cell lung cancer (NSCLC) cell resistance to cisplatin (DDP). METTL14, miR-19a-5p, RBM24, and AXIN1 expressions in NSCLC tissues/cells were determined. DDP-resistant cell line was obtained, followed by the interference of METTL14 expression. NSCLC cells were treated with DDP to establish a drug-resistant cell line, and METTL14 expression in cells was intervened. The IC50 of NSCLC cells to DDP was measured by CCK-8 assay. NSCLC cell proliferation and apoptosis were observed by clone formation assay and flow cytometry. The content of m⁶A in total RNA in tissues and cells of NSCLC patients was detected using m⁶A Methylation Quantification Kit. The expressions of DGCR8-bound pri-miR-19a and m⁶A-modified pri-miR-19a were detected. The binding relationships between miR-19a-5p and RBM24 and RBM24 and AXIN1 were validated using dual-luciferase assay and RNA immunoprecipitation. Finally, mouse xenograft tumor model was established to verify the role of METTL14 in vivo. METTL14 was highly expressed in NSCLC. METTL14 silencing diminished IC50 to DDP, repressed NSCLC cell proliferation, and enhanced apoptosis. METTL14-mediated m⁶A induced recognition and processing of pri-miR-19a by DGCR8, thus promoting the transition of pri-miR-19a to miR-19a-5p, repressing RBM24 expression, reducing the binding of RBM24 and AXIN1, and suppressing AXIN1 transcription. miR-19a-5p overexpression or RBM24/AXIN1 silencing abolished the effect of METTL14 silencing on NSCLC cell resistance to DDP. METTL14 silencing in vivo enhanced the suppressive role of DDP to tumor growth. Collectively, METTL14-mediated m⁶A modification facilitated NSCLC cell resistance to DDP via miR-19a-5p/RBM24/AXIN1 axis. KEY MESSAGES: • METTL14 is highly expressed NSCLC and further increased in DDP-resistant cells. • METTL14 silencing attenuates DDP resistance of NSCLC cells. • METTL14 promotes the nature of pri-miR-19a by upregulating pri-miR-19a m6A level. • miR-19a-5p targets RBM24, thus reducing the binding of RBM24 and AXIN1 and inhibiting AXIN1 transcription. • METTL14 silencing in vivo enhances the suppressive role of DDP to tumor growth.

Epigenetics alternation in lung fibrosis and lung cancer

Respiratory disease including interstitial lung diseases (ILDs) and lung cancer is a group of devastating diseases that linked with increased morbidity and healthcare burden. However, respiratory diseases cannot be fully explained by the alternation of genetic information. Genetic studies described that epigenetic mechanisms also participate to transmit genetic information. Recently, many studies demonstrated the role of altered epigenetic modification in the pathogenesis of lung cancer and pulmonary fibrosis. Due to lacking effective medication, the underlying pathophysiological processes and causal relationships of lung diseases with epigenetic mechanisms still need to be better understood. Our present review provided a systematic revision of current knowledge concerning diverse epigenetic aberrations in major lung diseases, with special emphasis on DNA methylation, histone modifications, lncRNAs profiles, telomere patterns, as well as chromatin-remodelling complexes. We believed that a new target therapy for lung disease based on findings of the involved epigenetic pathway is a promising future direction.

Extracellular Vesicles Derived from Bone Marrow in an Early Stage of Ionizing Radiation Damage Are Able to Induce Bystander Responses in the Bone Marrow

Ionizing radiation (IR)-induced bystander effects contribute to biological responses to radiation, and extracellular vesicles (EVs) play important roles in mediating these effects. In this study we investigated the role of bone marrow (BM)-derived EVs in the bystander transfer of radiation damage. Mice were irradiated with 0.1Gy, 0.25Gy and 2Gy, EVs were extracted from the BM supernatant 24 h or 3 months after irradiation and injected into bystander mice. Acute effects on directly irradiated or EV-treated mice were investigated after 4 and 24 h, while late effects were investigated 3 months after treatment. The acute effects of EVs on the hematopoietic stem and progenitor cell pools were similar to direct irradiation effects and persisted for up to 3 months, with the hematopoietic stem cells showing the strongest bystander responses. EVs isolated 3 months after irradiation elicited no bystander responses. The level of seven microRNAs (miR-33a-3p, miR-140-3p, miR-152-3p, miR-199a-5p, miR-200c-5p, miR-375-3p and miR-669o-5p) was altered in the EVs isolated 24 hour but not 3 months after irradiation. They regulated pathways highly relevant for the cellular response to IR, indicating their role in EV-mediated bystander responses. In conclusion, we showed that only EVs from an early stage of radiation damage could transmit IR-induced bystander effects.

Clinical Significance of Histone Deacetylase (HDAC)-1, -2, -4 and -6 Expression in Salivary Gland Tumors

Salivary gland tumors (SGTs) comprise a group of rare neoplasms. Locally aggressive, recurrent and/or metastatic SGTs are notorious for their resistance to systemic therapy, making the need for carefully designed, prospective and randomized trials with useful predictive markers mandatory to define new effective therapeutic protocols. Histone Deacetylases (HDACs), are thought to play a crucial role in carcinogenesis. They affect the DNA structure, being also able to regulate its transcription, repair, and replication. This study aimed to evaluate-to our knowledge for the first time-the HDAC-1, -2, -4 and -6 immunohistochemical expression in SGTs and their potential use as prognostic biomarkers. Medical records and archival histopathological material of 58 (36 benign and 22 malignant) SGT patients were included in this study. The H-score was statistically correlated with the clinicopathological characteristics for all cases and patients' survival rate in malignant SGTs. HDAC-2 positivity was significantly associated with more prolonged overall survival (OS) of patients with malignant SGTs (p = 0.028), while HDAC-2 positivity and no HDAC-6 expression were associated with prolonged OS of patients with HG malignant SGT (p = 0.003 and p = 0.043, respectively). Additionally, a high HDAC-2 H-score was significantly associated with longer OS for HG malignant SGT patients (p = 0.027). In our study, HDAC-2 expression is a marker for good prognosis, whereas HDAC-6 expression indicated poor prognosis; thus, an inhibitor of HDAC-6 may be used to improve patients' survival.

Clinical significance of HDAC1, -2 and -3 expression levels in esophageal squamous cell carcinoma

The present study analyzed the expression of the histone deacetylase (HDAC) 1, 2 and 3 in primary esophageal squamous cell carcinoma (ESCC) samples and how their levels correlate with clinicopathological parameters. ESCC patients (n=88) in the present study had received no previous treatment before undergoing surgical excision. The mRNA expression of HDAC1, -2 and -3 were detected by semi-quantified PCR in ESCC samples and distal normal samples. The relationship of HDAC1, -2 and -3 expression with clinicopathological parameters was analyzed by χ2 test. The correlation among these HDACs was analyzed by Pearson's correlation test. Compared with distal normal tissues, ESCC samples had higher expression of HDAC1, but not HDAC2 or HDAC3 (P<0.05). The expression of HDACs was different between Kazak and Han ethnicities. The expression of HDAC2 was correlated with invasion depth (P<0.05), but not with sex, age, metastasis, or the degree of tumor differentiation (P>0.05). There was no association between HDAC1 or HDAC3 and clinicopathological parameters (P>0.05). For the Kazak and Han ethnicities, HDAC1 expression was present in male patients, patients with well/moderate differentiated ESCC and T3 and T4 ESCC (P<0.01). HDAC1 in patients aged <60 was associated with ethnicity (P<0.05). HDAC2 expression was different in positive LN metastasis, well/moderate differentiation and T3 and T4 ESCC (P<0.01). HDAC3 expression in male patients, patients with negative LN metastasis and well/moderate differentiation ESCC was associated with ethnicity (P<0.05). Additionally, the expression levels of HDAC1, -2 and -3 did not correlate with each other. Thus, HDAC1 expression may be used as a risk factor for ESCC and HDAC2 levels may be used to predict invasion depth. The expression of HDAC1, -2 and -3 has ethnic differences.

Integrative data modeling from lung and lymphatic cancer predicts functional roles for miR-34a and miR-16 in cell fate regulation

MiR-34a and miR-16 coordinately control cell cycle checkpoint in non-small cell lung cancer (NSCLC) cells. In cutaneous T-cell lymphoma (CTCL) cells miR-16 regulates a switch between apoptosis and senescence, however the role of miR-34a in this process is unclear. Both miRNAs share many common targets and experimental evidences suggest that they synergistically control the cell-fate regulation of NSCLC. In this work we investigate whether the coordinate action between miR-34a and miR-16 can explain experimental results in multiple cell lines of NSCLC and CTCL. For that we propose a Boolean model of the G1/S checkpoint regulation contemplating the regulatory influences of both miRNAs. Model validation was performed by comparisons with experimental information from the following cell lines: A549, H460, H1299, MyLa and MJ presenting excellent agreement. The model integrates in a single logical framework the mechanisms responsible for cell fate decision in NSCLC and CTCL cells. From the model analysis we suggest that miR-34a is the main controller of miR-16 activity in these cells. The model also allows to investigate perturbations of single or more molecules with the purpose to intervene in cell fate mechanisms of NSCLC and CTCL cells.

Histone deacetylase HDAC1 expression correlates with the progression and prognosis of lung cancer: A meta-analysis

BACKGROUND

Histone deacetylase 1 (HDAC1) is an important epigenetic factor, and is thought to be associated with the progression and prognosis of some types of cancer. HDAC1 has been reported to be overexpressed in lung cancer, but the correlation between HDAC1 overexpression and the clinical features or prognosis of lung cancer is controversial. In this study, we investigated the potential association between HDAC1 and lung cancer.

MATERIALS AND METHODS

Embase, Web of Science, PubMed, and other sources were searched for relevant studies. Pooled odds ratios (ORs) or hazard ratios (HRs) with 95% confidence interval (CI) were calculated to evaluate the association of HDAC1 with lung cancer risk.

RESULTS

Eight eligible studies were included in the final meta-analysis. We found that HDAC1 mRNA or protein expression was closely associated with the differentiation grade of lung cancer (OR = 2.36, 95% CI = 1.14-4.87, P = .02). In addition, the protein expression level of HDAC1 in squamous cell carcinoma was higher than that in adenocarcinoma (OR = 1.81, 95% CI = 1.13-2.90, P = .01). Finally, HDAC1 mRNA or protein expression was negatively correlated with the overall survival rate of patients with lung cancer (HR = 2.40, 95% CI = 1.48-3.88, P = .0004).

CONCLUSION

In this meta-analysis, our results suggest that HDAC1 may serve as a good diagnostic and prognostic marker for lung cancer.

Distinct Patterns of Expression of Transcription Factors in Response to Interferonβ and Interferonλ1

After viral infection, type I and III interferons (IFNs) are coexpressed by respiratory epithelial cells (RECs) and activate the ISGF3 transcription factor (TF) complex to induce expression of a cell-specific set of interferon-stimulated genes (ISGs). Type I and III IFNs share a canonical signaling pathway, suggesting that they are redundant. Animal and in vitro models, however, have shown that they are not redundant. Because TFs dictate cellular phenotype and function, we hypothesized that focusing on TF-ISG will reveal critical combinatorial and nonredundant functions of type I or III IFN. We treated BEAS-2B human RECs with increasing doses of IFNβ or IFNλ1 and measured expression of TF-ISG. ISGs were expressed in a dose-dependent manner with a nonlinear jump at intermediate doses. At subsaturating combinations of IFNβ and IFNλ1, many ISGs were expressed in a pattern that we modeled with a cubic equation that mathematically defines this threshold effect. Uniquely, IFNβ alone induced early and transient IRF1 transcript and protein expression, while IFNλ1 alone induced IRF1 protein expression at low levels that were sustained through 24 h. In combination, saturating doses of these 2 IFNs together enhanced and sustained IRF1 expression. We conclude that the cubic model quantitates combinatorial effects of IFNβ and IFNλ1 and that IRF1 may mediate nonredundancy of type I or III IFN in RECs.

A correlation analysis between HDAC1 over-expression and clinical features of laryngeal squamous cell carcinoma

CONCLUSION

HDAC1 may be a prognostic biomarker for LSCC malignant potency and a potent factor resulting in decreased sensitivity of LSCC in radiotherapy.

OBJECTIVE

The aim of this study was to evaluate the correlation between histone deacetylase 1 (HDAC1) over-expression and clinical features in laryngeal squamous cell carcinoma (LSCC).

METHODS

This study assessed the HDAC1 expressions in 90 formalin-fixed paraffin-embedded LSCC samples, 30 adjacent non-neoplastic tissues, and 30 laryngeal polyp tissues by immunohistochemistry (IHC). In addition, another 40 LSCC samples were collected that were divided into two groups after 3-month radiotherapy: the high radio-sensitive group (HRS) and low radio-sensitive group (LRS). Overall survival curves of all the LSCC patients were constructed by Kaplan-Meier method and long-rank test.

RESULTS

All ninety samples were positively immunostained for HDAC1. The expression of HDAC1 was up-regulated and significantly associated with T classification, lymph node metastases, tumor location and clinical stage. HDAC1 was mainly labeled in the epithelial cells of laryngeal polyp tissues and adjacent non-neoplastic tissues. In addition, the expression of HDAC1 was significantly higher in LRS than that in HRS. The positive rates for stage III-IV tumor were significantly higher than those for stage II. LSCC patients with HDAC1 over-expression and LRS presented a shorter 5-year overall survival rate.

Histone deacetylase 2 controls p53 and is a critical factor in tumorigenesis

Histone deacetylase 2 (HDAC2) regulates biological processes by deacetylation of histones and non-histone proteins. HDAC2 is overexpressed in numerous cancer types, suggesting general cancer-relevant functions of HDAC2. In human tumors the TP53 gene encoding p53 is frequently mutated and wild-type p53 is often disarmed. Molecular pathways inactivating wild-type p53 often remain to be defined and understood. Remarkably, current data link HDAC2 to the regulation of the tumor suppressor p53 by deacetylation and to the maintenance of genomic stability. Here, we summarize recent findings on HDAC2 overexpression in solid and hematopoietic cancers with a focus on mechanisms connecting HDAC2 and p53 in vitro and in vivo. In addition, we present an evidence-based model that integrates molecular pathways and feedback loops by which p53 and further transcription factors govern the expression and the ubiquitin-dependent proteasomal degradation of HDAC2 and of p53 itself. Understanding the interactions between p53 and HDAC2 might aid in the development of new therapeutic approaches against cancer.

Effects of carbon-ion beam irradiation on the angiogenic response in lung adenocarcinoma A549 cells

Radiotherapy has been focused mainly on killing cancer cells, and little attention has been paid to the process supporting tumor growth and metastasis, including the process of angiogenesis. To investigate the effects of carbon-ion irradiation on angiogenesis in lung cancer cells, we examined the expression of vascular endothelial growth factor and basic fibroblast growth factor in the tumor conditioned medium (TCM) of A549 cells exposed to carbon-ion or X-ray irradiation, as well as endothelial cell growth, invasion, and tube formation induced by TCM. No changes in vascular endothelial growth factor secretion were detected in the TCM of A549 cells exposed to carbon-ion irradiation at 2 or 4 Gy, whereas 1 Gy of irradiation significantly decreased vascular endothelial growth factor and basic fibroblast growth factor levels. Carbon-ion irradiation at 1 Gy inhibited endothelial cell invasion and tube formation. The TCM from A549 cells irradiated with X-ray promoted angiogenesis, whereas the TCM of A549 cells exposed to carbon-ion irradiation at 2 or 4 Gy had no effect. These findings suggest that carbon-ion irradiation at 1 Gy significantly suppressed the process of angiogenesis in vitro by inhibiting endothelial cell invasion and tube formation, which are related to vascular endothelial growth factor and basic fibroblast growth factor production.

SNP rs10248565 in HDAC9 as a novel genomic aberration biomarker of lung adenocarcinoma in non-smoking women

BACKGROUND

Numerous efforts have been made to elucidate the etiology and improve the treatment of lung cancer, but the overall five-year survival rate is still only 15%. Although cigarette smoking is the primary risk factor for lung cancer, only 7% of female lung cancer patients in Taiwan have a history of smoking. Since cancer results from progressive accumulation of genetic aberrations, genomic rearrangements may be early events in carcinogenesis.

RESULTS

In order to identify biomarkers of early-stage adenocarcinoma, the genome-wide DNA aberrations of 60 pairs of lung adenocarcinoma and adjacent normal lung tissue in non-smoking women were examined using Affymetrix Genome-Wide Human SNP 6.0 arrays. Common copy number variation (CNV) regions were identified by ≥30% of patients with copy number beyond 2 ± 0.5 of copy numbers for each single nucleotide polymorphism (SNP) and at least 100 continuous SNP variant loci. SNPs associated with lung adenocarcinoma were identified by McNemar's test. Loss of heterozygosity (LOH) SNPs were identified in ≥18% of patients with LOH in the locus. Aberration of SNP rs10248565 at HDAC9 in chromosome 7p21.1 was identified from concurrent analyses of CNVs, SNPs, and LOH.

CONCLUSION

The results elucidate the genetic etiology of lung adenocarcinoma by demonstrating that SNP rs10248565 may be a potential biomarker of cancer susceptibility.

New insights into the regulation of Axin function in canonical Wnt signaling pathway

The Wnt signaling pathway plays crucial roles during embryonic development, whose aberration is implicated in a variety of human cancers. Axin, a key component of canonical Wnt pathway, plays dual roles in modulating Wnt signaling: on one hand, Axin scaffolds the “β-catenin destruction complex” to promote β-catenin degradation and therefore inhibits the Wnt signal transduction; on the other hand, Axin interacts with LRP5/6 and facilitates the recruitment of GSK3 to the plasma membrane to promote LRP5/6 phosphorylation and Wnt signaling. The differential assemblies of Axin with these two distinct complexes have to be tightly controlled for appropriate transduction of the “on” or “off” Wnt signal. So far, there are multiple mechanisms revealed in the regulation of Axin activity, such as post-transcriptional modulation, homo/hetero-polymerization and auto-inhibition. These mechanisms may work cooperatively to modulate the function of Axin, thereby playing an important role in controlling the canonical Wnt signaling. In this review, we will focus on the recent progresses regarding the regulation of Axin function in canonical Wnt signaling.

[Research advance on mechanism and application of HATs and HDACs in epithelial-mesenchymal transition of lung cancer]

肺癌是危害我国人民健康与生命的重大疾病之一, 肺癌的复发和死亡多源于肿瘤转移。上皮细胞的间质化过程(epithelial-mesenchymal transition, EMT)是肺癌转移中的一个关键步骤, 此过程涉及E-cadherin表达下调, 并受到EMT转录因子调控。组蛋白乙酰转移酶(histone acetyltransferases, HATs)和组蛋白去乙酰化酶(histone deacetyltransferases, HDACs)是催化组蛋白乙酰化和去乙酰化的蛋白家族, 不仅在肿瘤进程中发挥重要功能, 近年来发现它们同样参与肺癌EMT过程。HATs与HDACs和某些EMT转录因子有相互作用。而且, 这些EMT转录因子的功能受乙酰化调控, 并影响肺癌EMT进程。本文将分别介绍HATs和HDACs参与肺癌EMT的作用机理, 从分子机制方面对它们之间的相互作用进行探讨, 并讨论HDAC抑制剂在抑制EMT和肺癌治疗方面的潜在应用价值, 以期为相关基础研究和临床实践提供借鉴。

MicroRNA-449a enhances radiosensitivity in CL1-0 lung adenocarcinoma cells

Lung cancer is the leading cause of cancer-related mortality worldwide. Radiotherapy is often applied for treating lung cancer, but it often fails because of the relative non-susceptibility of lung cancer cells to radiation. MicroRNAs (miRNAs) have been reported to modulate the radiosensitivity of lung cancer cells and have the potential to improve the efficacy of radiotherapy. The purpose of this study was to identify a miRNA that can adjust radiosensitivity in lung adenocarcinoma cells. Two lung adenocarcinoma cell lines (CL1-0 and CL1-5) with different metastatic ability and radiosensitivity were used. In order to understand the regulatory mechanisms of differential radiosensitivity in these isogenic tumor cells, both CL1-0 and CL1-5 were treated with 10 Gy radiation, and were harvested respectively at 0, 1, 4, and 24 h after radiation exposure. The changes in expression of miRNA upon irradiation were examined using Illumina Human microRNA BeadChips. Twenty-six miRNAs were identified as having differential expression post-irradiation in CL1-0 or CL1-5 cells. Among these miRNAs, miR-449a, which was down-regulated in CL1-0 cells at 24 h after irradiation, was chosen for further investigation. Overexpression of miR-449a in CL1-0 cells effectively increased irradiation-induced DNA damage and apoptosis, altered the cell cycle distribution and eventually led to sensitization of CL1-0 to irradiation.