Analysis of the occurrence and distribution of primary and recurrent basal cell carcinoma of head and neck coupled to the assessment of tumor microenvironment and Sonic hedgehog signaling

Publisher Copyright: © 2020, Editura Academiei Romane. All rights reserved.Often, basal cell carcinoma (BCC) displays local aggressiveness, and when developed in the head and neck presents with deep tissue invasion and recurrence. Previous studies have pointed out the necessity of systematic assessment of primary and recurrent BCC based on a better understanding of the biology and function of its microenvironment. Although hedgehog-dependent tumor cells signaling to the underlying stroma, and vice versa, have been demonstrated to be implicated in the pathogenesis of BCC, little is known about peculiarities of the tumor microenvironment and the above-mentioned signaling in the head and neck. The occurrence and distribution of 79 primary and recurrent BCCs developed in the head and neck region were estimated. The data were coupled with the immunohistochemical assessment of type IV collagen, laminin, alpha-smooth muscle actin (α-SMA), and Sonic hedgehog (Shh). The frequency of the mixed BCCs and the predominance of the nose and cheek region affection by primary and recurrent tumors were demonstrated. Furthermore, the increase of peritumoral and entire stromal α-SMA immunoreactivity in the mixed recurrent BCC was confirmed using statistics. We found the increase of strong levels of Shh immunoexpression in the aggressive variants of BCC - infiltrative, mixed, and micronodular. Surprisingly, we confirmed the upregulation of Shh paralleled by the downregulation of α-SMA immunoexpression in the superficial subtype of the tumor. Our results suggest the necessity of further studies assessing the nature of the tumor along with the peculiarities of signaling in BCCs of head and neck.publishersversionPeer reviewe

Ultrastructural Characterization of the Frontal Lobe in the Case of Human Herpes Virus-6 Infection

The vast majority of the world’s population is exposed to beta-herpesviruses during early childhood. After the primary infection, human herpesvirus-6 (HHV-6) can establish a lifelong persistence. The role of HHV-6 in the development of neurodegenerative disorders is not completely clarified. Postmortem samples of brain tissue obtained from 24 elderly subjects with unspecified encephalopathy were used in the study. Nested (nPCR) and real-time polymerase chain reaction (RT PCR) were used for the qualitative and quantitative detection of viral genomic sequences in isolated DNA from frontal lobe samples. For ultrastructural examination, transmission electron microscopy (TEM), nPCR, and immunohistochemically confirmed HHV-6-positive tissue samples were used. Immunogold (IG) labeling using anti-HHV-6 (20) mouse monoclonal antibodies, raised against viral lysate (Santa Cruz Biotechnology, dilution 1:30), was performed. HHV-6 DNA was detected in 38% (9/24) of the frontal lobe tissue samples. The HHV-6 load in the nPCR-positive samples ranged from 10 to 3878.5 (copies/106 cells). A TEM examination of the frontal cortex revealed lipofuscin containing neurons, glial cells, unmyelinated and small myelinated axons, and symmetric synapses. Subcortical brain regions revealed glial cells interspersed by myelinated axons. The expression of viral proteins was found in the nuclei of neurons, demonstrating disarranged chromatin. HHV-6 positivity was detected between the adjacent cisternae of the rough endoplasmic reticulum of neurons displaying IG labeling. Furthermore, products of IG labeling were found in nuclei and cytoplasm of oligodendrocytes. The cytoplasm of astrocytes was IG labeled as well. IG labeling was used to determine the presence and intracellular localization of HHV-6 proteins in the human brain. HHV-6 possibly contributes to the demyelination process via entry into and affection of oligodendrocytes. Finally, neural susceptibility to HHV-6 may be linked to an invalid cellular immune response, followed by the development of a persistent viral infection

Synovitis in osteoarthritic patients : Morphological and virological evidence of its contribution to development of the disease

Funding Information: This study was supported by the National Research Programme Biomedicine for the Public Health (BIOMEDICINE), project 7.2 and the Latvian Council of Science, project [Interdisciplinary study of inflammatory joint disease-associated influence on neurocognitive function], project No. lzp-2018/1-0149. Finally, the authors would like to thank the Roche Academy for providing the study reagents. Publisher Copyright: © 2019 Mihails Tarasovs et al., published by Sciendo 2019. Copyright: Copyright 2019 Elsevier B.V., All rights reserved.The role of inflammation in the development of osteoarthritic joint degeneration is not completely understood. Recent data suggest that processes that cause and orchestrate inflamed synovial lesions may be implicated in the development of the disease. The morphological changes of the synovium in patients with osteoarthritis (OA), as well as the level of synovial inflammation cautiously graded, in association to the presence of human parvovirus B19 (B19V) infection markers, were evaluated. Qualitative and quantitative detection of B19V genomic sequence was performed in OA and rheumatoid arthritis (RA) groups. The expression of CD68, S100 (Ca2+ binding proteins soluble in 100% ammonium sulfate) and B19 VP1/VP2 capsid proteins found in the synovium were investigated by single and double immunolabeling, whereas fine features of synoviocytes - by electron microscopy. One-third of OA and RA patients demonstrated synovial expression of B19V antigen, which was confirmed in both types of synoviocytes. The overall expression of B19V in OA patients was weaker than that found in RA subjects. Positive correlation between B19V-positive vascular endothelial cells, sublining infiltrating lymphocytes, macrophages, and B19V-positive synoviocytes was established. No correlation between synovitis score indices as well as the expression of S100 and expression of B19V was found. The results suggest that the synovial membrane maintains local joint homeostasis, and that virus mediated synovitis is implicated in the development of OA.Peer reviewe

Immunological mechanisms of autoimmune thyroid diseases : A shift in the traditional TH1/TH2 paradigm

Funding Information: This work was supported by the Latvian Council of Science project No. lzp-2018/2-0059. Publisher Copyright: © 2019 Tatjana Zaķe et al., published by Sciendo 2019.Autoimmune thyroid diseases (AITD) mainly include Hashimoto's thyroiditis (HT) and Graves' disease (GD), which are characterised by the presence of circulating antibodies against various thyroid autoantigens and infiltration of the thyroid gland by autoreactive lymphocytes. Despite the significant advancement in the knowledge of AITD pathogenesis in the last decade, the specific immunological mechanisms responsible for development of the disease are not thoroughly understood. Classically, HT has long been considered as a T helper (Th)1-mediated disease, while a Th2-driven autoimmune response is dominant for GD development. However, this classification has changed due to the description of Th17 lymphocytes, which suggested participation of these cells in AITD, particularly HT pathogenesis. Moreover, a shift in the balance between Th17 and T regulatory (Treg) cells has been observed in thyroid autoimmunity. We have observed overexpression of IL-17, the prominent effector cytokine of Th17, within thyroid tissues from HT and GD patients in our studies. The present review will focus on recent data regarding the role of Treg and Th17 lymphocytes in AITD pathogenesis. In addition, the impact and proposed mechanisms of the predominant environmental factors triggering the autoimmune response to the thyroid will be discussed.publishersversionPeer reviewe

Heterogeneity of tissue IL-17 and tight junction proteins expression demonstrated in patients with autoimmune thyroid diseases

Funding Information: Funding/support: This study was supported in part by the Latvian National Research Program “BIOMEDICINE” No. 5.2.4. For the statistical analyses, the authors were assisted by the Department of Public Health and Epidemiology at Riga Stradins University. Publisher Copyright: Copyright © 2018 the Author(s). Published by Wolters Kluwer Health, Inc.Th17 cells together with their hallmark cytokine interleukin (IL)-17 were identified as crucial contributing factors in the pathogenesis of thyroid autoimmunity. The cytokine-regulated tight junction (Tj) disruption is thought to be essential in the initiation and/or development of several diseases. Still, the role of IL-17 maintaining Tj integrity in autoimmune thyroid diseases (AITDs) has not yet been evaluated. We aimed to investigate integrity of the thyroid follicle by studying immunoexpression of cellular Tj - zonula occludens (ZO)-1 and claudin-1 proteins coupled to IL-17A and CD68 detection in AITD patients compared with controls. Thirty-five adult patients undergoing thyroidectomy and presenting 18 cases of Hashimoto thyroiditis (HT), 7 of Graves' disease (GD) as well as 10 subjects of colloid goiter without autoimmune component served as controls were enrolled in this study. An immunohistochemical analysis including IL-17A, ZO-1, claudin-1, and CD68 detection was performed in each case. The correlation of IL-17A with Tj and CD68 in patients with AITD was also analyzed. Apart from inflammatory cells, we evidenced a stronger expression level of IL17A in the thyroid follicular cells in HT patients when compared with GD or colloid goiter. A significant reduction of ZO-1 immunoreactivity was observed in the thyrocytes in HT patients, whereas no significant differences were found in claudin-1 expression in HT and GD compared with colloid goiter patients. A significantly higher number of thyroid follicles with CD68-positive cells was found in HT patients than that in patients with GD or colloid goiter. In HT patients, the expression of IL-17A in the follicular cells was positively correlated with CD68 immunopositivity, whereas no association with claudin-1 or ZO-1 expression was found. GD patients did not reveal any significant correlation of IL-17A with Tj and CD68. Strong overexpression of IL-17A observed in the thyroid epithelial cells is associated with the presence of intrafollicular CD68-positive cells in HT patients. We evidenced the changes in molecules of thyrocyte junctional complexes highlighting impairment of the thyroid follicle integrity in HT, but no association with IL-17A was found.publishersversionPeer reviewe

Identification of High-Risk Human Papillomavirus DNA, p16, and E6/E7 Oncoproteins in Laryngeal and Hypopharyngeal Squamous Cell Carcinomas

Funding Information: The authors would like to thank the Riga Stradi?? University Department of Doctoral studies for reagents and publishing support. We would also like to thank Elza Rate, MD at the Department of Head and Neck Surgery, Oncology Centre of Latvia, for additional support with the collection of some tumor specimens. We are grateful to Simons Svirskis for his valuable help with statistical analysis. Publisher Copyright: © 2021 by the authors. Licensee MDPI, Basel, Switzerland.Human papillomavirus (HPV) was proven to play a significant role in cancer development in the oropharynx. However, its role in the development of laryngeal (LSCC) and hypopharyngeal squamous cell carcinoma (HPSCC) remains to be clarified. High-risk HPV (HR-HPV) viral proteins E6 and E7 are considered to be pertinent to HPV-related carcinogenesis. Hence, our aim was to estimate LSCC and HPSCC for HR-HPV DNA, p16, and E6/E7 oncoprotein status by using molecular virology and immunohistochemistry methods. The prevalence of HPV16 infection was 22/41 (53.7%) and 20/31 (64.5%) for LSCC and HPSCC, accordingly. The majority of HPV16+ tumor samples were stage III or IV. In most samples, the presence of either HPV16 E6 or HPV16 E7 viral protein in dysplastic or tumor cells was confirmed using immunohistochemistry. Our results suggest a high prevalence of HPV16 as a primary HR-HPV type in LSCC and HPSCC. The lack of HPV E6/E7 oncoproteins in some tumor samples may suggest either the absence of viral integration or the presence of other mechanisms of tumorigenesis. The utilization of p16 IHC as a surrogate marker of HR-HPV infection is impractical in LSCC and HPSCC.publishersversionPeer reviewe

The Role of the p16 and p53 Tumor Suppressor Proteins and Viral HPV16 E6 and E7 Oncoproteins in the Assessment of Survival in Patients with Head and Neck Cancers Associated with Human Papillomavirus Infections

Funding Information: This research was supported by the European Social Fund and the Latvian state budget within the frame of the project No. 8.2.2.0/20/l/004 “Support for involving doctoral students in scientific research and studies” at Riga Stradiņš University. The article processing charge was covered by Riga Stradinš University Department of Otorhinolaryngology. Publisher Copyright: © 2023 by the authors.The role of HPV in the survival prognosis of patients with head and neck squamous cell carcinoma, especially patients with laryngeal squamous cell carcinoma (LSCC) and hypopharyngeal squamous cell carcinoma (HPSCC), is still somewhat ambiguous. The present study aimed to explore the significance of tumor suppressor proteins and HPV16 E6 and E7 oncoproteins in the assessment of survival in patients with oropharyngeal squamous cell carcinoma (OPSCC), LSCC, and HPSCC associated with high-risk (HR-) and low-risk (LR-) HPV infections. By utilizing molecular and immunohistochemical investigations of HNSCC samples and patient data, univariate and multivariate survival analyses were conducted. The presence of HPV DNA (LR- and HR-HPV) was associated with a better 5-year OS and DSS for OPSCC and LSCC. The IHC overexpression of HPV16 E6 protein and p16 protein was associated with better survival in the univariate (for OPSCC) and multivariate (OPSCC and HPSCC) survival analyses. The overexpression of p53 was associated with better survival in OPSCC. HPV infection plays a significant role in the tumorigenesis of HNSCC, and the immunohistochemical assessment of HPV16 E6 protein expression should be interpreted as a useful prognostic marker for OPSCC and HPSCC.publishersversionPeer reviewe

Effect of Human Herpesviruses 6 and 7 Infection on the Clinical Course of Rheumatoid Arthritis

Publisher Copyright: © 2016 by Anda Kadiša. Copyright: Copyright 2018 Elsevier B.V., All rights reserved.Rheumatoid arthritis (RA) is a chronic systemic autoimmune inflammatory disease affecting joints and causing symmetrical chronic progressive aseptic synovitis and erosive-destructive changes. Viruses and viral infections are considered to be the main risk factors for autoimmune disease development (especially for individuals with genetic predisposition). The goal of this study was to evaluate the frequency of HHV-6 and HHV-7 persistent infection and its activity phase in RA and osteoarthritis (OA) patients, and healthy persons. We examined also the influence of HHV-6 and-7 infections on RA activity, aggressiveness, radiographical stage, and frequency of complications as well as the presence of HHV-6 infection markers in synovial fluid and synovial tissues of RA joints of affected patients. Despite the lack of significant correlation between frequency of persistent single HHV-6, single HHV-7, and concurrent HHV-6 and HHV-7 infection and RA clinical course, we found that both active and latent HHV-6 and/or HHV-7 infection increased RA activity and progression in several clinical and laboratory parameters. Regarding the severity of the course of RA, we observed also a high prevalence of RA complications in the patient group with active single HHV-6 infection and also a more severe radiographical stage in RA patients with active concurrent HHV-6 and HHV-7 infection. Moreover, viral infection markers were found in synovial fluid and synovial tissues of affected joints of RA patients. This suggests that HHV-6 and/or HHV-7 infection has effect on the disease clinical course, but virus reactivation may be a consequence of immunosuppressive treatment.Peer reviewe

Prevalence, Cell Tropism, and Clinical Impact of Human Parvovirus Persistence in Adenomatous, Cancerous, Inflamed, and Healthy Intestinal Mucosa

Parvoviruses are single-stranded DNA viruses, infecting many animals from insects to humans. Human parvovirus B19 (B19V) causes erythema infectiosum, arthropathy, anemia, and fetal death, and human bocavirus (HBoV) 1 causes respiratory tract infections, while HBoV2-4 are enteric. Parvoviral genomes can persist in diverse non-permissive tissues after acute infection, but the host-cell tropism and the impact of their tissue persistence are poorly studied. We searched for parvoviral DNA in a total of 427 intestinal biopsy specimens, as paired disease-affected and healthy mucosa, obtained from 130 patients with malignancy, ulcerative colitis (UC), or adenomas, and in similar intestinal segments from 55 healthy subjects. Only three (1.6%) individuals exhibited intestinal HBoV DNA (one each of HBoV1, 2, and 3). Conversely, B19V DNA persisted frequently in the intestine, with 50, 47, 31, and 27% detection rates in the patients with malignancy, UC, or adenomas, and in the healthy subjects, respectively. Intra-individually, B19V DNA persisted significantly more often in the healthy intestinal segments than in the inflamed colons of UC patients. The highest loads of B19V DNA were seen in the ileum and colon specimens of two healthy individuals. With dual-RNAscope in situ hybridization and immunohistochemistry assays, we located the B19V persistence sites of these intestines in mucosal B cells of lymphoid follicles and vascular endothelial cells. Viral messenger RNA transcription remained, however, undetected. RNA sequencing (RNA-seq) identified 272 differentially expressed cellular genes between B19V DNA-positive and -negative healthy ileum biopsy specimens. Pathway enrichment analysis revealed that B19V persistence activated the intestinal cell viability and inhibited apoptosis. Lifelong B19V DNA persistence thus modulates host gene expression, which may lead to clinical outcomes.Peer reviewe

Plexus brachialis strain and compression deformation in the costo-axillary-brachial region : A cadaveric study

Objective: The aim of this study was to clarify the role of different mechanisms in nerve injury during arm abduction positions. The tasks were to determine the strain deformation of the plexus brachialis during arm abduction, to measure the pressures in the neurovascular bundle in the cervico-costoclavicular-axillary area, and evaluate the histological changes of nerve after the stretch test. Material and Methods: During the cadaveric study on 7 specimens 7-20 h after death, strain deformation of plexus brachialis as well as compression deformation caused by the surrounding structures of the neurovascular bundle were investigated in the arm abduction position of 0°, 90°, 12°, 150°, and 180°. One nerve sample was studied histologically after 15% stretch on the bench. Results: The relative strain deformation of 3%-23% was documented during 0° to 180° abduction tests. The strain deformation from 0° to 90° was significant (P<0.001). The mean pressure change in the bundle was 13.6 mm Hg at 90°, 53.7 mm Hg at 120°, 73.4 mm Hg at 150°, and 89.0 mm Hg at 180° arm abduction. An increase in pressure was significant in the intervals: 0°-90° (P<0.001), 91°-120° (P<0.001), 121°-150° (P<0.001) and 151°-180° (P<0.05). Conclusions: Nerve traction and tissue compression arising during the arm abduction above 90° were found to be sufficient to induce lesions in neural bundles of the plexus brachialis.publishersversionPeer reviewe