Nuclear matrix protein SMAR1 represses c-Fos-mediated HPV18 E6 transcription through alteration of chromatin histone deacetylation

Advances in cervical cancer: current insights and future directions

In alignment with the World Health Organization's strategy to eliminate cervical cancer, substantial progress has been made in the treatment of this malignancy. Cervical cancer, largely driven by human papillomavirus (HPV) infection, is considered preventable and manageable because of its well-established etiology. Advancements in precision screening technologies, such as DNA methylation triage, HPV integration detection, liquid biopsies, and artificial intelligence-assisted diagnostics, have augmented traditional screening methods such as HPV nucleic acid testing and cytology. Therapeutic strategies aimed at eradicating HPV and reversing precancerous lesions have been refined as pivotal measures for disease prevention. The controversy surrounding surgery for early-stage cervical cancer revolves around identifying optimal candidates for minimally invasive and conservative procedures without compromising oncological outcomes. Recent clinical trials have yielded promising results for the development of systemic therapies for advanced cervical cancer. Immunotherapies, such as immune checkpoint inhibitors (ICIs), antibody-drug conjugates (ADCs), and targeted therapy have demonstrated significant effectiveness, marking a substantial advancement in cervical cancer management. Various combination therapies have been validated, and ongoing trials aim to enhance outcomes through the development of novel drugs and optimized combination regimens. The prospect of eradicating cervical cancer as the first malignancy to be eliminated is now within reach. In this review, we provide a comprehensive overview of the latest scientific insights, with a particular focus on precision managements for various stages of cervical disease, and explore future research directions in cervical cancer.

Non-Hormonal Therapy for Endometriosis Based on Angiogenesis, Oxidative Stress and Inflammation

Endometriosis is a common gynecological disease that occurs in between 6 and 10% of women who are at reproductive maturity. The presence of endometrial tissue outside the uterine cavity is the defining characteristic of this disease. Although the etiology of endometriosis remains controversial, there is a general consensus that multiple biological processes such as angiogenesis and vasculogenesis, oxidative stress, and inflammation contribute to its complex pathophysiology. Patients' expectations and priorities influence the treatment plan that is selected. For instance, therapy with hormone medications is inappropriate for endometriosis patients who wish to become pregnant since these medications interfere with ovulation. On the other hand, considering that the current endometriosis treatments are associated with recurrence of pain and disease despite the treatment of the disease and have many side effects, the design and application of non-hormonal drugs in this field is very necessary. Therefore, in this article, we tried to have an overview on non-hormonal treatments by considering angiogenesis, oxidative stress, and inflammation as important biological processes involved in endometriosis.

The research progress on radiation resistance of cervical cancer

Cervical carcinoma is the most prevalent gynecology malignant tumor and ranks as the fourth most common cancer worldwide, thus posing a significant threat to the lives and health of women. Advanced and early-stage cervical carcinoma patients with high-risk factors require adjuvant treatment following surgery, with radiotherapy being the primary approach. However, the tolerance of cervical cancer to radiotherapy has become a major obstacle in its treatment. Recent studies have demonstrated that radiation resistance in cervical cancer is closely associated with DNA damage repair pathways, the tumor microenvironment, tumor stem cells, hypoxia, cell cycle arrest, and epigenetic mechanisms, among other factors. The development of tumor radiation resistance involves complex interactions between multiple genes, pathways, and mechanisms, wherein each factor interacts through one or more signaling pathways. This paper provides an overview of research progress on an understanding of the mechanism underlying radiation resistance in cervical cancer.

Structural insights into DNA recognition by the BEN domain of the transcription factor BANP

The BEN domain-containing transcription factors regulate transcription by recruiting chromatin-modifying factors to specific chromatin regions via their DNA-binding BEN domains. The BEN domain of BANP has been shown to bind to a CGCG DNA sequence or an AAA-containing MARs (matrix attachment regions) DNA sequence. Consistent with these in vivo observations, we identified an optimal DNA binding sequence of AAATCTCG by PBM (protein binding microarray), which was also confirmed by our ITC (Isothermal Titration Calorimetry) and mutagenesis results to uncover additional mechanistic details about DNA binding by the BEN domain of BANP. We then determined crystal structures of the BANP BEN domain in apo form and in complex with a CGCG-containing DNA, respectively, which revealed that the BANP BEN domain mainly used the electrostatic interactions to bind DNA with some base-specific interactions with the TC motifs. Our ITC results also showed that BANP bound to unmethylated and methylated DNAs with comparable binding affinities. Our complex structure of BANP-mCGCG revealed that the BANP BEN domain bound to the unmethylated and methylated DNAs in a similar mode and cytosine methylation did not get involved in binding, which is also consistent with our observations from the complex structures of the BEND6 BEN domain with the CGCG or CGmCG DNAs. Taken together, our results further elucidate the elements important for DNA recognition and transcriptional regulation by the BANP BEN domain-containing transcription factor.

The Emerging Role of Histone Deacetylase Inhibitors in Cervical Cancer Therapy

Cervical carcinoma is one of the most common cancers among women globally. Histone deacetylase inhibitors (HDACIs) constitute anticancer drugs that, by increasing the histone acetylation level in various cell types, induce differentiation, cell cycle arrest, and apoptosis. The aim of the current review is to study the role of HDACIs in the treatment of cervical cancer. A literature review was conducted using the MEDLINE and LIVIVO databases with a view to identifying relevant studies. By employing the search terms "histone deacetylase" and "cervical cancer", we managed to identify 95 studies published between 2001 and 2023. The present work embodies the most up-to-date, comprehensive review of the literature centering on the particular role of HDACIs as treatment agents for cervical cancer. Both well-established and novel HDACIs seem to represent modern, efficacious anticancer drugs, which, alone or in combination with other treatments, may successfully inhibit cervical cancer cell growth, induce cell cycle arrest, and provoke apoptosis. In summary, histone deacetylases seem to represent promising future treatment targets in cervical cancer.

Advances in epigenetic modifications and cervical cancer research

Cervical cancer (CC) is an important public health problem for women, and perspectives and information regarding its prevention and treatment are quickly evolving. Human papilloma virus (HPV) has been recognized as a major contributor to CC development; however, HPV infection is not the only cause of CC. Epigenetics refers to changes in gene expression levels caused by non-gene sequence changes. Growing evidence suggests that the disruption of gene expression patterns which were governed by epigenetic modifications can result in cancer, autoimmune diseases, and various other maladies. This article mainly reviews the current research status of epigenetic modifications in CC based on four aspects, respectively DNA methylation, histone modification, noncoding RNA regulation and chromatin regulation, and we also discuss their functions and molecular mechanisms in the occurrence and progression of CC. This review provides new ideas for early screening, risk assessment, molecular targeted therapy and prognostic prediction of CC.

Dietary supplements for treatment of endometriosis: A review

As search for optimal therapy continues for endometriosis, aid of dietary supplements is gaining attention. Supplements can be used for their anti-inflammatory, anti-oxidant, anti-proliferative and immune modulatory charactheristics. We reviewed the literature, evaluated and synthesized effects of vitamin D, zinc, magnesium, omega 3, propolis, quercetin, curcumin, N-acetylcysteine, probiotics, resveratrol, alpha lipoic acid, vitamin C, vitamin E, selenium and epigallocatechin-3-gallate. Based on results of in vitro, animal and human studies, it might be safe to say that dietary supplements can be used as a complementary treatment for endometriosis.

Pathogen-Induced Epigenetic Modifications in Cancers: Implications for Prevention, Detection and Treatment of Cancers in Africa

Cancer is a major public health burden worldwide. Tumor formation is caused by multiple intrinsic and extrinsic factors. Many reports have demonstrated a positive correlation between the burden of infectious pathogens and the occurrence of cancers. However, the mechanistic link between pathogens and cancer development remains largely unclear and is subject to active investigations. Apart from somatic mutations that have been widely linked with various cancers, an appreciable body of knowledge points to alterations of host epigenetic patterns as key triggers for cancer development. Several studies have associated various infectious pathogens with epigenetic modifications. It is therefore plausible to assume that pathogens induce carcinogenesis via alteration of normal host epigenetic patterns. Thus, Africa with its disproportionate burden of infectious pathogens is threatened by a dramatic increase in pathogen-mediated cancers. To curb the potential upsurge of such cancers, a better understanding of the role of tropical pathogens in cancer epigenetics could substantially provide resources to improve cancer management among Africans. Therefore, this review discusses cancer epigenetic studies in Africa and the link between tropical pathogens and cancer burden. In addition, we discuss the potential mechanisms by which pathogens induce cancers and the opportunities and challenges of tropical pathogen-induced epigenetic changes for cancer prevention, detection and management.

Curcumin induced the cell death of immortalized human keratinocytes (HaCaT) through caspase-independent and caspase-dependent pathways

Curcumin is a diketone compound found in turmeric. It is used as food additives and spices, and has anti-proliferation and anti-cancer properties. However, the effect of curcumin on human keratinocytes (KCs) is still unclear. In this study, curcumin dramatically inhibited the cell growth of immortalized human KCs (HaCaT) and arrested the cells at the G2/M phase, with an apoptosis rate of 33.95% after 24 μM curcumin treatment. HaCaT cells showed changes in typical apoptotic morphology and the configuration of nuclear matrix-intermediate filaments (NM-IFs) after treatment with curcumin. We identified 16 differentially expressed nuclear matrix (NM) proteins, including apoptosis inducing factor (AIF) and caspase 3, by 2-DE and MALDI-TOF/TOF mass spectrometry. The expression of AIF decreased in the mitochondria and increased in the nucleus. Immunofluorescence assays showed that AIF was released from the mitochondria to the nucleus. AIF silencing and caspase inhibitor (z-vad-fmk) both lead to HaCaT cells being insensitive to apoptosis induced by curcumin. Meanwhile, after curcumin treatment, mitochondrial membrane depolarization led to cytochrome c release from the mitochondria to the cytoplasm, and the ratio of Bax to Bcl-2 in HaCaT cells was also increased, which subsequently initiated the activation of caspase-3. These results suggest that curcumin-induced apoptosis of HaCaT cells occurs not only through the caspase-dependent pathway but also through the caspase-independent pathway. This discovery enhances the development and utilization of curcumin and provides possible evidence for the treatment of proliferative skin diseases, including skin cancer.

Molecular pathways in the development of HPV-induced cervical cancer

Recently, human papillomavirus (HPV) has gained considerable attention in cervical cancer research studies. It is one of the most important sexually transmitted diseases that can affect 160 to 289 out of 10000 persons every year. Due to the infectious nature of this virus, HPV can be considered a serious threat. The knowledge of viral structure, especially for viral oncoproteins like E6, E7, and their role in causing cancer is very important. This virus has different paths (PI3K/Akt, Wnt/β-catenin, ERK/MAPK, and JAK/STAT) that are involved in the transmission of signaling paths through active molecules like MEK (pMEK), ERK (pERK), and Akt (pAkt). It's eventually through these paths that cancer is developed. Precise knowledge of these paths and their signals give us the prognosis to adopt appropriate goals for prevention and control of these series of cancer.

SMAR1 repression by pluripotency factors and consequent chemoresistance in breast cancer stem-like cells is reversed by aspirin

The high abundance of drug efflux pumps in cancer stem cells (CSCs) contributes to chemotherapy resistance. The transcriptional regulator SMAR1 suppresses CSC expansion in colorectal cancer, and increased abundance of SMAR1 is associated with better prognosis. Here, we found in breast tumors that the expression of SMAR1 was decreased in CSCs through the cooperative interaction of the pluripotency factors Oct4 and Sox2 with the histone deacetylase HDAC1. Overexpressing SMAR1 sensitized CSCs to chemotherapy through SMAR1-dependent recruitment of HDAC2 to the promoter of the gene encoding the drug efflux pump ABCG2. Treating cultured CSCs or 4T1 tumor-bearing mice with the nonsteroidal anti-inflammatory drug aspirin restored SMAR1 expression and ABCG2 repression and enhanced tumor sensitivity to doxorubicin. Our findings reveal transcriptional mechanisms regulating SMAR1 that also regulate cancer stemness and chemoresistance and suggest that, by restoring SMAR1 expression, aspirin might enhance chemotherapeutic efficacy in patients with stem-like tumors.

Pyridoxine enhances chemo-responsiveness of breast cancer stem cells via redox reconditioning

A plethora of molecular strategies are employed by breast cancer stem cells (bCSCs) to evade chemotherapy-induced death signals, redox modulation being a crucial factor among those. Here, we observed that bCSCs are resistant to DNA damage and generate low ROS upon doxorubicin (Dox) treatment. Further exploration revealed inherently high NEIL2, a base excision repair (BER) enzyme that plays a key regulatory role in repairing DNA damage, in bCSCs. However, its role in modulating the redox status of bCSCs remains unexplored. In addition, Dox not only upregulates NEIL2 in bCSCs at both transcriptional and translational levels but also declines p300-induced acetylation thus activating NEIL2 and providing a protective effect against the stress inflicted by the genotoxic drug. However, when the redox status of bCSCs is altered by inducing high ROS, apoptosis of the resistant population is accomplished. Subsequently, when NEIL2 is suppressed in bCSCs, chemo-sensitization of the resistant population is enabled by redox reconditioning via impaired DNA repair. This signifies a possibility of therapeutically disrupting the redox balance in bCSCs to enhance their chemo-responsiveness. Our search for an inhibitor of NEIL2 revealed that vitamin B6, i.e., pyridoxine (PN), hinders NEIL2-mediated transcription-coupled repair process by not only decreasing NEIL2 expression but also inhibiting its association with RNA Pol II, thus stimulating DNA damage and triggering ROS. As a consequence of altered redox regulation, bCSCs become susceptible towards Dox, which then induces apoptosis via caspase cascade. These findings signify that PN enhances chemo-responsiveness of bCSCs via redox reconditioning.

The AP-1 pathway; A key regulator of cellular transformation modulated by oncogenic viruses

Cancer progression is critically associated with modulation of host cell signaling pathways. Activator protein-1 (AP-1) signaling is one such pathway whose deregulation renders the host more susceptible to cancer development. Oncogenic viruses, including hepatitis B virus, hepatitis C virus, human papilloma virus, Epstein-Barr virus, human T-cell lymphotropic virus type 1, and Kaposi's sarcoma-associated herpes virus, are common causes of cancer. This review discusses how these oncoviruses by acting through various aspects of the host cell signaling machinery such as the AP-1 pathway might affect oncoviral tumorigenesis, replication, and pathogenesis. The review also briefly considers how the pathway might be targeted during infections with these oncogenic viruses.

Histone deacetylases in virus-associated cancers

Oncogenic viruses are one of the most important causes of cancer worldwide. The pathogens contribute to the establishment of human malignancies by affecting various cellular events. Epigenetic mechanisms, such as histone modification methylation/demethylation, are one of the most critical events manipulated by oncogenic viruses to drive tumorigenesis. Histone modifications are mediated by histone acetylation and deacetylation, regulated by histone acetyltransferases (HATs) and histone deacetylases (HDACs), respectively. Dysregulation of HDACs activity affects viral tumorigenesis in several ways, such as manipulating tumor suppressor and viral gene expression. The present review aims to describe the vital interactions between both cancer-caused/associated viruses and the HDAC machinery, particularly by focusing on those viruses involved in gastrointestinal tumors, as some of the most common viral-mediated cancers.

Aspirin enhances cisplatin sensitivity of resistant non-small cell lung carcinoma stem-like cells by targeting mTOR-Akt axis to repress migration

Conventional chemotherapeutic regimens are unable to prevent metastasis of non-small cell lung carcinoma (NSCLC) thereby leaving cancer incurable. Cancer stem cells (CSCs) are considered to be the origin of this therapeutic limitation. In the present study we report that the migration potential of NSCLCs is linked to its CSC content. While cisplatin alone fails to inhibit the migration of CSC-enriched NSCLC spheroids, in a combination with non-steroidal anti inflammatory drug (NSAID) aspirin retards the same. A search for the underlying mechanism revealed that aspirin pre-treatment abrogates p300 binding both at TATA-box and initiator (INR) regions of mTOR promoter of CSCs, thereby impeding RNA polymerase II binding at those sites and repressing mTOR gene transcription. As a consequence of mTOR down-regulation, Akt is deactivated via dephosphorylation at Ser⁴⁷³ residue thereby activating Gsk3β that in turn causes destabilization of Snail and β-catenin, thus reverting epithelial to mesenchymal transition (EMT). However, alone aspirin fails to hinder migration since it does not inhibit the Integrin/Fak pathway, which is highly activated in NSCLC stem cells. On the other hand, in aspirin pre-treated CSCs, cisplatin stalls migration by hindering the integrin pathway. These results signify the efficacy of aspirin in sensitizing NSCLC stem cells towards the anti-migration effect of cisplatin. Cumulatively, our findings raise the possibility that aspirin might emerge as a promising drug in combinatorial therapy with the existing chemotherapeutic agents that fail to impede migration of NSCLC stem cells otherwise. This may consequently lead to the advancement of remedial outcome for the metastatic NSCLCs.

A novel isothiocyanate derivative inhibits HIV-1 gene expression and replication by modulating the nuclear matrix associated protein SMAR1

The essential role of SMAR1 in HIV-1 transcription and LTR driven gene expression suggests SMAR1 as an HIV dependency factor (HDF) and a potential anti-HIV therapeutic target. Here, we report for the first time, anti-HIV activity of 8 novel isothiocyanate (ITC) derivatives that differentially stabilise SMAR1. Out of 8 novel ITC derivatives, SCS-OCL-381 was observed to inhibit HIV-1 replication most significantly at the noncytotoxic concentration in reporter T-cell line, CEM-GFP. Further, the highly conserved anti-HIV activity of SCS-OCL-381 is a cell type, virus isolate and viral load independent phenomena and is approximately 3 fold more effective than the representative ITC, Sulforaphane (SFN). Further, SCS-OCL-381 does not hamper the activity of viral enzymes reverse transcriptase, integrase and protease. Mechanistically, SCS-OCL-381 stabilises SMAR1 which, otherwise undergoes proteasomal degradation upon HIV-1 infection in T-cells. This stabilisation results in the recruitment of repressor complex on HIV-1 LTR resulting in repression of LTR mediated transcription and gene expression. These inhibitory consequences were further confirmed by reporter based LTR activity assays in different cell lines. Taken together, these findings highlight the anti-HIV potential of novel ITC derivatives by the stabilisation of SMAR1 and strongly support further in vivo characterisation and potential translational applications of SCS-OCL-381.

Apoptosis of mouse myeloma cells induced by curcumin via the Notch3-p53 signaling axis

Resistance to apoptosis is a characteristic of cancer. Curcumin has become a potential anticancer drug for its pro-apoptotic effects, but the underlying mechanisms remain unclear. Furthermore, the Notch3-p53 signaling axis serves an important role in cell fate. The present study was designed to investigate the antitumor effect of curcumin by the Notch3-p53 axis in mouse myeloma P3X63Ag8 cells. The effects of curcumin on the viability of P3X63Ag8 cells were evaluated using an MTT assay. Quantitative expression of the Notch3-p53 signaling axis-associated genes was measured by reverse transcription-quantitative polymerase chain reaction, and western blot analysis was used to investigate the expression of proteins. Additionally, flow cytometry was used to measure the ratio of apoptosis. The results demonstrated that curcumin could significantly inhibit cell viability. No significant pro-apoptotic effect was observed when the concentration of curcumin was <30 µM. At 30 µM, curcumin-treated cells exhibited an apoptotic phenomenon, and the ratio of late apoptosis increased with the concentration of curcumin, and reached 28.4 and 51.8% in the medium- and high-dose groups, respectively. Curcumin inhibited the expression of Notch3, while the middle- and high-dose groups promoted p53. The expression of Notch3-responsive genes Hes family BHLH transcription factor 1 and Hes-related family transcription factor with YRPW motif 1 were notably promoted. Curcumin treatment significantly downregulated B-cell lymphoma-2 (Bcl-2) at the mRNA and protein levels, but upregulated Bcl-2-associated X. These data indicated that curcumin exhibited antitumor effects in mouse myeloma cells with induction of apoptosis by affecting the Notch3-p53 signaling axis.

Vorinostat, a pan-HDAC inhibitor, abrogates productive HPV-18 DNA amplification

Human papillomaviruses (HPVs) cause epithelial proliferative diseases. Persistent infection of the mucosal epithelia by the high-risk genotypes can progress to high-grade dysplasia and cancers. Viral transcription and protein activities are intimately linked to regulation by histone acetyltransferases and histone deacetylases (HDACs) that remodel chromatin and regulate gene expression. HDACs are also essential to remodel and repair replicating chromatin to enable the progression of replication forks. As such, Vorinostat (suberoylanilide hydroximic acid), and other pan-HDAC inhibitors, are used to treat lymphomas. Here, we investigated the effects of Vorinostat on productive infection of the high-risk HPV-18 in organotypic cultures of primary human keratinocytes. HPV DNA amplifies in the postmitotic, differentiated cells of squamous epithelia, in which the viral oncoproteins E7 and E6 establish a permissive milieu by destabilizing major tumor suppressors, the pRB family proteins and p53, respectively. We showed that Vorinostat significantly reduced these E6 and E7 activities, abrogated viral DNA amplification, and inhibited host DNA replication. The E7-induced DNA damage response, which is critical for both events, was also compromised. Consequently, Vorinostat exposure led to DNA damage and triggered apoptosis in HPV-infected, differentiated cells, whereas uninfected tissues were spared. Apoptosis was attributed to highly elevated proapoptotic Bim isoforms that are known to be repressed by EZH2 in a repressor complex containing HDACs. Two other HDAC inhibitors, Belinostat and Panobinostat, also inhibited viral DNA amplification and cause apoptosis. We suggest that HDAC inhibitors are promising therapeutic agents to treat benign HPV infections, abrogate progeny virus production, and hence interrupt transmission.

Morphoproteomics, E6/E7 in-situ hybridization, and biomedical analytics define the etiopathogenesis of HPV-associated oropharyngeal carcinoma and provide targeted therapeutic options

BACKGROUND

Human papillomavirus (HPV) has been identified as an etiopathogenetic factor in oropharyngeal squamous cell carcinoma. The HPV E6 and E7 oncogenes are instrumental in promoting proliferation and blocking differentiation leading to tumorigenesis. Although surgical intervention can remove such tumors, the potential for an etiologic field effect with recurrent disease is real. A downstream effector of E7 oncoprotein, enhancer of zeste homolog 2 (EZH2), is known to promote proliferation and to pose a block in differentiation and in turn, could lead to HPV-induced malignant transformation. However, the EZH2 pathway is amenable to low toxicity therapies designed to promote differentiation to a more benign state and prevent recurrent disease by inhibiting the incorporation of HPV into the genome. This is the first study using clinical specimens to demonstrate EZH2 protein expression in oropharyngeal carcinoma (OPC).

METHODS

The study included eight patients with oropharyngeal carcinoma, confirmed p16INK4a- positive by immunohistochemistry (IHC). The tissue expression of E6/E7 messenger RNA (mRNA) was measured by RNAscope® in-situ hybridization technology. Expression of EZH2, Ki-67, and mitotic indices were assessed by morphoproteomic analysis. Biomedical analytics expanded the results with data from Ingenuity Pathway Analysis (IPA) and KEGG databases to construct a molecular network pathway for further insights.

RESULTS

Expression of E6 and E7 oncogenes in p16INK4a- positive oropharyngeal carcinoma was confirmed. EZH2 and its correlates, including elevated proliferation index (Ki-67) and mitotic progression were also present. Biomedical analytics validated the relationship between HPV- E6 and E7 and the expression of the EZH2 pathway.

CONCLUSION

There is morphoproteomic and mRNA evidence of the association of p16INK4a-HPV infection with the E6 and E7 oncogenes and the expression of EZH2, Ki-67 and mitotic progression in oropharyngeal carcinoma. The molecular network biology was confirmed by biomedical analytics as consistent with published literature. This is significant because the biology lends itself to targeted therapeutic options using metformin, curcumin, celecoxib and sulforaphane as therapeutic strategies to prevent progression or recurrence of disease.

Genome-wide association study of copy number variation with lung function identifies a novel signal of association near BANP for forced vital capacity

BACKGROUND

Genome-wide association studies of Single Nucleotide Polymorphisms (SNPs) have identified 55 SNPs associated with lung function. However, little is known about the effect of copy number variants (CNVs) on lung function, although CNVs represent a significant proportion of human genetic polymorphism. To assess the effect of CNVs on lung function quantitative traits, we measured copy number at 2788 previously characterised, common copy number variable regions in 6 independent cohorts (n = 24,237) using intensity data from SNP genotyping experiments. We developed a pipeline for genome-wide association analysis and meta-analysis of CNV genotypes measured across multiple studies using SNP genotype array intensity data from different platform technologies. We then undertook cohort-level genome-wide association studies of CNV with lung function in a subset of 4 cohorts (n < =12,403) with lung function measurements and meta-analysed the results. Follow-up was undertaken for CNVs which were well tagged by SNPs, in up to 146,871 individuals.

RESULTS

We generated robust copy number calls for 1962 out of 2788 (70 %) known CNV regions genome-wide, with 1103 measured with compatible class frequencies in at least 2 cohorts. We report a novel CNV association (discovery P = 0.0007) with Forced Vital Capacity (FVC) downstream of BANP on chromosome 16 that shows evidence of replication by a tag SNP in two independent studies (replication P = 0.004). In addition, we provide suggestive evidence (discovery P = 0.0002) for a role of complex copy number variation at a previously reported lung function locus, containing the rootletin gene CROCC, that is not tagged by SNPs.

CONCLUSIONS

We demonstrate how common CNV regions can be reliably and consistently called across cohorts, using an existing calling algorithm and rigorous quality control steps, using SNP genotyping array intensity data. Although many common biallelic CNV regions were well-tagged by common SNPs, we also identified associations with untagged mulitallelic CNV regions thereby illustrating the potential of our approach to identify some of the missing heritability of complex traits.

A model for the control of DNA integrity by the sperm nuclear matrix

The highly condensed chromatin of mammalian spermatozoa is usually considered to be biologically inert before fertilization. However, we have demonstrated that even in this compacted state, sperm chromatin is subject to degradation at open configurations associated with the nuclear matrix through a process we have termed sperm chromatin fragmentation (SCF). This suggests that a mechanism exists to monitor the health of spermatozoa during transit through the male reproductive tract and to destroy the genome of defective sperm cells. The site of DNA damage in SCF, the matrix attachment sites, are the same that we hypothesize initiate DNA synthesis in the zygote. When sperm that have damaged DNA are injected into the oocyte, the newly created zygote responds by delaying DNA synthesis in the male pronucleus and, if the damage is severe enough, arresting the embryo's development. Here we present a model for paternal DNA regulation by the nuclear matrix that begins during sperm maturation and continues through early embryonic development.

Aspirin inhibits epithelial-to-mesenchymal transition and migration of oncogenic K-ras-expressing non-small cell lung carcinoma cells by down-regulating E-cadherin repressor Slug

Background

Cancer metastasis is one of the most common causes of treatment failure and death in cancer patients. It has been acknowledged that aberrant activation of epithelial-to-mesenchymal transition (EMT) program, endows cancer cells with metastatic competence for which E-cadherin switch is a well-established hallmark. Suppression of E-cadherin by its transcriptional repressor Slug is thus a determining factor for EMT. Here, we aimed at discerning (i) the molecular mechanisms that regulate Slug/E-cadherin axis in oncogenic K-ras-expressing non-small cell lung carcinoma (NSCLC) cells, and (ii) the effect of aspirin in modulating the same.

Methods

The migratory behaviour of NSCLC cell line A549 were deciphered by wound healing assay. Further assessment of the molecular mechanisms was done by western blotting, RT-PCR, confocal microscopy, chromatin immunoprecipitation and small interfering RNA (siRNA)-mediated gene silencing.

Results

Here we report that in oncogenic K-ras-expressing A549 cells, Ras/ERK downstream Elk-1 forms p-Elk-1-p300 complex that being directly recruited to SLUG promoter acetylates the same to ensure p65NFκB binding for transcriptional up-regulation of Slug, a transcriptional repressor of E-cadherin. Aspirin inhibits EMT and decelerates the migratory potential of A549 cells by down-regulating Slug and thereby up-regulating E-cadherin. Aspirin impedes activation and nuclear translocation of p65NFκB, essential for this transcription factor being available for SLUG promoter binding. As a consequence, Slug transcription is down-regulated relieving A549 cells from Slug-mediated repression of E-cadherin transcription, thereby diminishing the metastatic potential of these oncogenic Ras-expressing NSCLC cells.

Conclusions

Cumulatively, these results signify a crucial role of the anti-inflammatory agent aspirin as a novel negative regulator of epithelial-to-mesenchymal transition thereby suggesting its candidature as a promising tool for deterring metastasis of highly invasive K-ras-expressing NSCLC cells.

Electronic supplementary material

The online version of this article (doi:10.1186/s12885-016-2078-7) contains supplementary material, which is available to authorized users.

Novel naproxen-peptide-conjugated amphiphilic dendrimer self-assembly micelles for targeting drug delivery to osteosarcoma cells

The aim of the current study was to synthesize and prepare novel self-assembly micelles loaded with curcumin (Cur) based on naproxen (Nap)-conjugated amphiphilic peptide dendrimers.

Tumor Restrictive Suicide Gene Therapy for Glioma Controlled by the FOS Promoter

Effective suicide gene delivery and expression are crucial to achieving successful effects in gene therapy. An ideal tumor-specific promoter expresses therapeutic genes in tumor cells with minimal normal tissue expression. We compared the activity of the FOS (FBJ murine osteosarcoma viral oncogene homolog) promoter with five alternative tumor-specific promoters in glioma cells and non-malignant astrocytes. The FOS promoter caused significantly higher transcriptional activity in glioma cell lines than all alternative promoters with the exception of CMV. The FOS promoter showed 13.9%, 32.4%, and 70.8% of the transcriptional activity of CMV in three glioma cell lines (U87, U251, and U373). Importantly, however, the FOS promoter showed only 1.6% of the transcriptional activity of CMV in normal astrocytes. We also tested the biologic activity of recombinant adenovirus containing the suicide gene herpes simplex virus thymidine kinase (HSV-tk) driven by the FOS promoter, including selective killing efficacy in vitro and tumor inhibition rate in vivo. Adenoviral-mediated delivery of the HSV-tk gene controlled by the FOS promoter conferred a cytotoxic effect on human glioma cells in vitro and in vivo. This study suggests that use of the FOS-tk adenovirus system is a promising strategy for glioma-specific gene therapy but still much left for improvement.

Mithramycin A sensitizes therapy-resistant breast cancer stem cells toward genotoxic drug doxorubicin

Chemotherapy resistance is a major clinical challenge for the management of locally advanced breast cancer. Accumulating evidence suggests a major role of cancer stem cells (CSCs) in chemoresistance evoking the requirement of drugs that selectively target CSCs in combination with chemotherapy. Here, we report that mithramycin A, a known specificity protein (Sp)1 inhibitor, sensitizes breast CSCs (bCSCs) by perturbing the expression of drug efflux transporters, ATP-binding cassette sub-family G, member 2 (ABCG2) and ATP-binding cassette sub-family C, member 1 (ABCC1), survival factors, B-cell lymphoma 2 (Bcl-2) and X-linked inhibitor of apoptosis (XIAP), and, stemness regulators, octamer-binding transcription factor 4 (Oct4) and Nanog, which are inherently upregulated in these cells compared with the rest of the tumor population. In-depth analysis revealed that aberrant overexpression of Sp1 in bCSCs transcriptionally upregulates (1) resistance-promoting genes to protect these cells from genotoxic therapy, and (2) stemness regulators to sustain self-renewal potential of these cells. However, mithramycin A causes transcriptional suppression of these chemoresistant and self-renewal genes by inhibiting Sp1 recruitment to their promoters. Under such antisurvival microenvironment, chemotherapeutic agent doxorubicin induces apoptosis in bCSCs via DNA damage-induced reactive oxygen species generation. Cumulatively, our findings raise the possibility that mithramycin A might emerge as a promising drug in combinatorial therapy with the existing chemotherapeutic agents that fail to eliminate CSCs. This will consequently lead to the improvement of therapeutic outcome for the treatment-resistant breast carcinomas.

Pathogenesis of human papillomavirus-associated mucosal disease

Human papillomaviruses (HPVs) are a necessary cause of carcinoma of the cervix and other mucosal epithelia. Key events in high-risk HPV (HRHPV)-associated neoplastic progression include persistent infection, deregulated expression of virus early genes in basal epithelial cells and genomic instability causing secondary host genomic imbalances. There are multiple mechanisms by which deregulated virus early gene expression may be achieved. Integration of virus DNA into host chromosomes is observed in the majority of cervical squamous cell carcinomas (SCCs), although in ∼15% of cases the virus remains extrachromosomal (episomal). Interestingly, not all integration events provide a growth advantage to basal cervical epithelial cells or lead to increased levels of the virus oncogenes E6 and E7, when compared with episome-containing basal cells. The factors that provide a competitive advantage to some integrants, but not others, are complex and include virus and host contributions. Gene expression from integrated and episomal HRHPV is regulated through host epigenetic mechanisms affecting the virus long control region (LCR), which appear to be of functional importance. New approaches to treating HRHPV-associated mucosal neoplasia include knockout of integrated HRHPV DNA, depletion of virus transcripts and inhibition of virus early gene transcription through targeting or use of epigenetic modifiers. Copyright © 2014 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.