Transcriptional activity of the long control region in human papillomavirus type 33 intratype variants.

Background: High-risk human papillomaviruses (HPVs) are responsible for the development of cervical and other anogenital cancers. Intratype sequence variants of certain high-risk HPV types (e.g.

Coordinated action of human papillomavirus type 16 E6 and E7 oncoproteins on competitive endogenous RNA (ceRNA) network members in primary human keratinocytes.

Background: miRNAs and lncRNAs can regulate cellular biological processes both under physiological and pathological conditions including tumour initiation and progression. Interactions between differentially expressed diverse RNA species, as a part of a complex intracellular regulatory network (ceRNA network), may contribute also to the pathogenesis of HPV-associated cancer. The purpose of this study was to investigate the global expression changes of miRNAs, lncRNAs and mRNAs driven by the E6 and E7 oncoproteins of HPV16, and construct a corresponding ceRNA regulatory network of coding and non-coding genes to suggest a regulatory network associated with high-risk HPV16 infections.

Orientation-dependent toxic effect of human papillomavirus type 33 long control region DNA in Escherichia coli cells.

The functional analysis of human papillomavirus (HPV) sequence variation requires the molecular cloning of different genomic regions of virus variants. In this study, we report an unexpected difficulty experienced when trying to clone HPV33 long control region (LCR) variants in Escherichia coli. Standard cloning strategies proved to be inappropriate to clone HPV33 LCR variants in the forward orientation into a eukaryotic reporter vector (pGL2-Basic).

The PTPN14 Tumor Suppressor Is a Degradation Target of Human Papillomavirus E7.

Activation of signaling pathways ensuring cell growth is essential for the proliferative competence of human papillomavirus (HPV)-infected cells. Tyrosine kinases and phosphatases are key regulators of cellular growth control pathways. A recently identified potential cellular target of HPV E7 is the cytoplasmic protein tyrosine phosphatase PTPN14, which is a potential tumor suppressor and is linked to the control of the Hippo and Wnt/beta-catenin signaling pathways.

Phylogenetic and functional analysis of sequence variation of human papillomavirus type 31 E6 and E7 oncoproteins.

High-risk human papillomaviruses (HPV) are the causative agents of cervical and other anogenital cancers as well as a subset of head and neck cancers. The E6 and E7 oncoproteins of HPV contribute to oncogenesis by associating with the tumour suppressor protein p53 and pRb, respectively. For HPV types 16 and 18, intratypic sequence variation was shown to have biological and clinical significance.

CpG methylation in human papillomavirus (HPV) type 31 long control region (LCR) in cervical infections associated with cytological abnormalities.

The mechanisms that regulate papillomavirus gene expression include DNA methylation. The transcription of papillomavirus oncogenes E6 and E7 is controlled by certain regulatory elements in the LCR, which include binding sites for the E2 protein, a viral regulator of oncogene expression. In HPV-31-infected exfoliated cervical cells, the CpG methylation of the entire LCR was determined by next-generation sequencing after bisulfite modification.

The Human Papillomavirus E6 PDZ Binding Motif: From Life Cycle to Malignancy.

Cancer-causing HPV E6 oncoproteins are characterized by the presence of a PDZ binding motif (PBM) at their extreme carboxy terminus. It was long thought that this region of E6 had a sole function to confer interaction with a defined set of cellular substrates. However, more recent studies have shown that the E6 PBM has a complex pattern of regulation, whereby phosphorylation within the PBM can regulate interaction with two classes of cellular proteins: those containing PDZ domains and the members of the 14-3-3 family of proteins.

Transcriptional regulation of genes involved in keratinocyte differentiation by human papillomavirus 16 oncoproteins.

The life cycle of human papillomaviruses (HPVs) is strictly linked to the differentiation of their natural host cells. The HPV E6 and E7 oncoproteins can delay the normal differentiation program of keratinocytes; however, the exact mechanisms responsible for this have not yet been identified. The goal of this study was to investigate the effects of HPV16 oncoproteins on the expression of genes involved in keratinocyte differentiation.

Microbiological profile of adenoid hypertrophy correlates to clinical diagnosis in children.

Objective: Adenoid hypertrophy is a common condition in childhood, which may be associated with recurring acute otitis media (RAOM), otitis media with effusion (OME), and obstructive sleep apnea syndrome (OSAS). These different clinical characteristics have some clinical overlap; however, they might be explained by distinct immunologic and infectious profiles and result in various histopathologic findings of adenoid specimens.

Methods: A total of 59 children with adenoid hypertrophy undergoing adenoidectomy were studied.

Elevated tumor necrosis factor-alpha expression in periapical lesions infected by Epstein-Barr virus.

Introduction: In apical periodontitis, there is an intense inflammatory response to endodontopathogenic bacteria, an essential component of the pathogenic microbiota. The inflammation can be aggravated by herpesviruses acting as nonessential pathogens in periapical lesions. This study aimed to determine the levels of tumor necrosis factor-alpha (TNF-α) and transforming growth factor-beta (TGF-β) in periapical lesions in relation to local occurrence of Epstein-Barr virus (EBV), human cytomegalovirus (HCMV), human herpesvirus 6 (HHV-6), and human herpesvirus 8 (HHV-8).

Sequence variation of human papillomavirus type 31 long control region: phylogenetic and functional implications.

About one-third of human papillomavirus (HPV) types infect the anogenital tract. High-risk genital HPV types (such as HPV 16, 18, 31, 33, and 35) are linked causally to the development of cervical cancer. The long control region (LCR) of the HPV genome regulates the replication and transcription of the viral genome.

Activation of Src, Fyn and Yes non-receptor tyrosine kinases in keratinocytes expressing human papillomavirus (HPV) type 16 E7 oncoprotein.

Background: The Src family tyrosine kinases (SFK) are cellular regulatory proteins that influence cell adhesion, proliferation, invasion and survival during tumor development. Elevated activity of Src was associated with increased cell proliferation and invasivity in human papillomavirus (HPV)-associated malignancies; therefore, transduced human foreskin keratinocytes (HFK) were used to investigate whether SFK activation is a downstream effect of papillomaviral oncoproteins. Activation of ubiquitously expressed SFKs, namely Src, Yes and Fyn, was investigated in both proliferating and differentiating keratinocytes.

[The prevalance of herpesviruses in human apical periodontitis samples].

Apical periodontitis is primarily initiated by the endodonto-patogen bacteria spreading from the inflamed or necrotic pulp tissues to the periapical area. Nevertheless, findings within the past years have established a pathogenic role of human herpesviruses such as Epstein-Barr virus (EBV) and human cytomegalovirus (HCMV) in periapical inflammations. The authors analysed the prevalence, activity and disease association of EBV, HCMV and human herpesvirus 6 (HHV-6) in 40 apical periodontitis samples and 40 healthy pulp controls.

Effects of human papillomavirus (HPV) type 16 oncoproteins on the expression of involucrin in human keratinocytes.

Background: The human papillomavirus (HPV) life cycle is closely linked to keratinocyte differentiation. Oncogenic HPV infection has been shown to hamper the normal differentiation of keratinocytes; however, the underlying mechanisms responsible for this phenomenon are yet to be clarified. Here, we aimed to study the effects of HPV16 E6 and E7 oncogenes on the expression of involucrin (IVL), an established marker of keratinocyte differentiation, in human foreskin keratinocyte (HFK) cells.

Association of human herpesvirus 6 subtypes with symptomatic apical periodontitis.

Objective: The occurrence of human herpesvirus (HHV) 6 subtypes A and B in apical periodontitis was determined. The relationship of HHV-6 subtypes to other disease associated herpesviruses, i.e.

Osteoprotegerin expression and sensitivity in otosclerosis with different histological activity.

Otosclerosis is a complex bone dystrophy of the human otic capsule leading to conductive and sensorineural hearing loss. Since otosclerosis may, at least in part, be considered as an autoimmune-inflammatory disease, disturbed balance of TNF-alpha and osteoprotegerin (OPG) expression has been implicated in the pathological bone remodeling. It has been supposed that active otosclerosis is characterized by decreased or missing local OPG production with invariable OPG sensitivity of the otosclerotic foci.

Prevalence and activity of Epstein-Barr virus and human cytomegalovirus in symptomatic and asymptomatic apical periodontitis lesions.

Introduction: Apical periodontitis is a polymicrobial inflammation with a dominant flora of opportunistic Gram-negative bacteria; however, a pathogenic role of human herpesviruses such as Epstein-Barr virus (EBV) and human cytomegalovirus (HCMV) has been implicated recently. The aims of this study were to determine the prevalence, activity, and disease association of EBV and HCMV in apical periodontitis in an Eastern Hungarian population.

Methods: Forty samples with apical periodontitis (17 symptomatic and 23 asymptomatic) and 40 healthy pulp controls were collected.

Detection and identification of CD46 splicing isoforms by nested RT-PCR.

CD46 (Membrane Cofactor Protein, MCP) is a transmembrane glycoprotein, which is expressed by all nucleated human cells whose purpose is to protect against autologous complement attack. In addition, CD46 can serve as a receptor for several viruses and bacteria and as a potent regulator of the inflammatory response by affecting T cell differentiation. Multiple isoforms of CD46 exist due to alternative splicing and are coexpressed in human cells in various patterns and expression levels.

Restriction analysis of otosclerosis-associated CD46 splicing variants.

Otosclerosis is a primary bone remodeling disorder of the human otic capsule and is associated with persistent measles virus infection. The human cellular receptor of measles virus is the membrane cofactor protein (MCP, CD46), which has 14 well-described splicing variants. Unique CD46 expression pattern of the otic capsule and the stapes footplate may determine the susceptibility for persistent measles virus infection.

Epigenetic alterations in cervical carcinogenesis.

During cervical carcinogenesis, the major etiologic factor, the persistent oncogenic HPV infection itself is not sufficient to immortalize and transform the epithelial host cells. Together with further genetic and epigenetic alterations disrupting the cell cycle control, the host cell acquires immortal phenotype and progresses further to an overt malignant and invasive phenotype. Here, we discuss how cancer-associated epigenetic alterations can affect the expression of papillomaviral as well as host genes in relation to stages representing the multistep process of carcinogenesis.

Disease-associated novel CD46 splicing variants and pathologic bone remodeling in otosclerosis.

Objective/hypothesis: Otosclerotic bone is supposed to show unique CD46 expression pattern because otosclerosis is an organ-specific disease with viral etiology.

Study Design: Otosclerosis is a complex bone remodeling disorder of the human otic capsule, which is associated with persisting measles virus infection. The general cellular receptor of measles virus is the CD46, which has 14-known splicing isoforms.

Adaptive host-abandonment of ectoparasites before fledging? Within-brood distribution of nest mites in house sparrow broods.

We studied the within-brood distribution of a haematophagous mite Pellonyssus reedi living on nestling house sparrows (Passer domesticus) near the time of fledging. We measured the natural level of infestation of individual nestlings, and determined the feeding efficiency of mites, by scoring their feeding status. Within-brood distribution of mite loads was unrelated to nestling body mass, tarsus length, or immunocompetence.

Lineage-specific silencing of human IL-10 gene expression by promoter methylation in cervical cancer cells.

Epigenetic analysis was performed to demonstrate that the normal and neoplastic epithelial cells do not serve as the source of the locally elevated IL-10 production during cervical carcinogenesis. Bisulfite sequencing was used to correlate promoter CpG methylation with the transcription of the gene. Lack of IL-10 transcription in HeLa, SiHa, Caski, HT-3, C33-A, HaCaT cell lines and in primary human keratinocytes correlated consistently with the methylated state of the proximal CpG residues, particularly with the two most proximal CpGs at positions -185 and -110.

Detection of osteoprotegerin and TNF-alpha mRNA in ankylotic Stapes footplates in connection with measles virus positivity.

Hypothesis: Otosclerosis is a bone remodeling disorder of the otic capsule causing conductive and sensorineural hearing loss. Persistent measles virus infection of the temporal bone with increased tumor necrosis factor (TNF)-alpha and decreased osteoprotegerin mRNA expression is supposed to be the main etiologic factor in otosclerosis.

Background: Determinants of measles virus infection and reactive inflammation were studied in otosclerosis.