The Acute Effects of Electronic Cigarette Vaping and Tobacco Cigarette Smoking on Choroidal Thickness in Young, Healthy, Habitual, Dual Smokers.

The present study aims to evaluate and compare the acute effects of tobacco cigarettes (TC) smoking and electronic cigarette (EC) vaping on foveal and choroidal thickness (CT) in young, healthy, dual smokers. Participants underwent four trials: 5 min TC; 5 min EC; 30 min EC; and 60 min nothing (sham trial). Scans before and immediately after each trial were obtained using spectral domain optical coherence tomography with the enhanced depth imaging mode. Changes in central foveal thickness (CFT), subfoveal choroidal thickness (SFCT), and CT at fourother points, 500 µm and 1000 µm temporally and nasally to the fovea, were measured. Forty-seven participants (33 male, 14 female; mean age 24.85 ± 1.57 years) were included. They smoked 13.53 ± 5.27 TCs/day for 6 ± 2.3 years and vaped ECs for the past 2.4 ± 1.08 years. We did not observe any statistically significant change in SFCT, CFT, and CT of the other points after any of the fourtrials. The acute changes in CFT and CT after EC vaping or TC smoking did not differ significantly compared to the sham trial. Smoking and vaping does not seem to result in statistically significant acute alterations in foveal and CT in young, dual smokers.

Comparative p16IKN4A Expression in Laryngeal Carcinoma and Cervical Cancer Precursors: A Real-time Grid-based Immunocytochemistry Analysis.

BACKGROUND/AIM: p16 (gene locus: 9p21) tumor suppressor gene is considered an important biomarker for the progression and prognosis in a variety of malignancies and pre-cancerous lesions, including high-risk (HR-) human papilloma virus (HPV)-mediated squamous intraepithelial lesions (SILs), based on cytological and the corresponding cervical intraepithelial neoplasia (CIN) histopathological categorization. p16 acts as a cyclin-dependent kinase-4 inhibitor negatively regulating the cell cycle. In persistent HPV infection, E7 oncogenic protein binds retinoblastoma protein leading to its proteolytic transformation, also triggering E2F dissociation, which increases DNA transcription and progression to S phase. This mechanism promotes aberrant p16 over-expression. Our aim was to comparatively analyze p16 protein expression patterns in laryngeal squamous cell carcinomas (LSCC) and also in SILs. MATERIALS AND METHODS: Fifty (n=50) primary LSCCs tissues all non-HPV-dependent, and a set of 50 liquid-based SILs, were analyzed by immunohistochemistry and immunocytochemistry, respectively. Concerning the screening process in cytological slides, a novel real-time reference and calibration grid platform was implemented and employed. RESULTS: Decreased protein expression was observed in 34/50 (68%) tissues regarding LSCCs. Overall p16 expression was associated to smoking status of the patients (p=0.001), and also with the p-stage of the examined malignancies (p=0.033). A strong statistical significance was assessed correlating LSIL/HSIL cases with a progressive p16 over expression (p=0.001), also reflecting a higher CIN diagnosis (p=0.001). CONCLUSION: p16 down-regulation is a frequent genetic event in LSCCs, which is associated with advanced disease. In contrast to this, p16 over-expression triggered by a specific molecular mechanism shows a strong relationship with a progressively aggressive phenotype due to upgraded SIL/CIN cervical categorization. The first described application of the grid platform demonstrated a considerable improvement in the immunocytochemistry slide screening process enhancing the diagnostic reliability.

Numerical Imbalances of Chromosome 7 in Oral Squamous Cell Carcinoma.

BACKGROUND: Oral squamous cell carcinoma (OSCC) is an aggressive neoplasm. Many chromosomal and gene alterations have been identified in OSCC, including structural and numerical changes. In this study, we implemented a molecular assay of chromosome 7 (Chr7) in order to investigate the level of its numerical instability in OSCC. MATERIALS AND METHODS: Using tissue microarray technology, 30 primary OSCCs were cored and re-embedded into one recipient block. Chromogenic in situ hybridization assay was performed based on Chr7 centromeric probedetection. RESULTS: Chr 7 numerical analysis detected polysomy (trisomy/ tetrasomy) in 4/30 (13.3%) of the examined tissue OSCC cores. Statistical significance was assessed correlating Chr7 numerical aberrations with stage (p=0.015), especially detected in cases not related to human papillomavirus (HPV) (p=0.01). CONCLUSION: Although Chr7 polysomy is a relatively rare gross genetic event in OSSC, it affects their biological behavior leading toa progressively aggressive phenotype (advanced stage). Furthermore, Chr7 polysomy is observed more frequently in non-viral (HPV) cases.

Deregulation of PTEN Expression in Laryngeal Squamous Cell Carcinoma Based on Tissue Microarray Digital Analysis.

BACKGROUND/AIM: Phosphatase and tensin homolog (PTEN) (gene locus: 10q23.3) -a tumor suppressor gene- is deleted, mutated or epigenetically hyper-methylated in a variety of malignancies. PTEN acts as a negative regulator in PI3K/AKT/mTOR signaling transduction pathway. Our aim was to investigate PTEN protein expression patterns in laryngeal squamous cell carcinomas (LSCC). MATERIALS AND METHODS: Using tissue microarray technology, fifty (n=50) primary LSCCs were cored and re-embedded into one recipient block. Immunohistochemistry and digital image analysis were implemented for evaluating protein expression levels. RESULTS: Abnormal protein expression (low to negative staining intensity values) was observed in 28/50 (56%) tissue cores. Overall PTEN expression was associated with the anatomical region of the malignancies (p=0.039), whereas a borderline correlation with the differentiation grade was also assessed (p=0.05). CONCLUSION: Aberrant expression of PTEN tumor-suppressor gene in LSCCs seems to affect their biological behavior. Well-differentiated tumors express moderate to high protein levels, an evidence of normal gene function, whereas loss of its expression correlates with a progressive tumor dedifferentiation. Additionally, loss of its expression is detected more frequently in specific anatomical regions of the larynx (glottis, predominantly, and partially supraglottis).

mTOR deregulation in oral cavity squamous cell carcinoma.

Signal transduction pathways consist of a variety of inter- and intra-cellular molecules. They act as supporting mechanisms for cell survival and homeostasis. Among them, the phosphatidylinositol 3-kinase (PI3K)/tumor suppressor phosphatase and tensin homologue deleted on chromosome ten (PTEN)/protein kinase B (Akt)/mammalian target of rapamycin (mTOR) pathway plays a crucial role in regulating normal cell growth based on growth factor receptors (GFRs) interaction, including epidermal GFR (type II-HER2) and insulin GFR (IGF). mTOR protein acts as a serine-threonine kinase that belongs to the PI3K-related kinase family. It mediates protein and lipid synthesis, mitochondrial metabolism, biogenesis, proliferation and also negatively regulates autophagy. Two distinct multiprotein complexes have been mainly identified and cloned: mTOR complex 1 (mTORC1) and mTOR complex 2 (mTORC2). mTOR is deregulated predominantly due to mutations, deletions, loss of heterozygosity (LOH) or abnormal phosphorylation of the upstream molecules inside the current pathway. Pure mTOR mutations are very rare. Development of specific inhibitors at the basis of targeted therapeutic strategies such as rapamycin (rapalogs) is an evolution in handling patients with mTOR abnormal overactivity. In the current special article we explored the role of the gene deregulation leading to abnormal protein expression in oral cavity squamous cell carcinoma (SCC).

Topoisomerase I deregulation in laryngeal squamous cell carcinomas based on tissue microarray analysis.

PURPOSE: Topoisomerases (types: I/IIa-b/IIIa-b) represent a super-family of nucleic enzymes involved in the DNA replication, transcription, recombination, and also chromosome topological formation. Topoisomerase's I (Topo I- gene location: 20q12) aberrant expression is a frequent genetic event in a variety of solid malignancies. Topo I inhibition promotes cell death due to DNA damage and for this reason it is a target for specific targeted chemotherapy (camptothecin, topotecan, irinotecan). Our aim was to investigate the role of abnormal Topo I protein expression in laryngeal squamous cell carcinomas (LSCC) in which there are very limited data regarding the influence of the marker. METHODS: Using tissue microarray (TMA) technology, 50 formalin-fixed, paraffin-embedded primary laryngeal SCCs were cored and re-pembedded into one recipient block. Immunohistochemistry was performed using anti- Topo I antibody. Digital image analysis was also implemented for evaluating objectively the protein expression levels on the corresponding stained nuclei. RESULTS: Topo I protein overexpression (moderate to high staining intensity values) was observed in 32/50 (64%) tissue cores, whereas low expression rates were detected in 18/50 (36%) cases. Topo I overall expression was strongly associated with the differentiation grade of the examined tumors (p=0.021). No other statistical correlations were identified. CONCLUSIONS: Topo I overexpression is observed in a significant subset of LSCCs affecting the level of differentiation in them. Additional molecular studies focused on the mechanism of Topo I gene/protein deregulation (i.e. amplification, abnormal epigenetic promoter methylation, mRNA aberrant expression) are necessary discriminating the eligible patients for applying specific chemotherapeutic strategies based on anti-Topo I agents.

Novel molecular and metabolic aspects in osteosarcoma.

Osteosarcoma (OS) is the most frequent bone-forming malignancy in children and adolescents. Concerning its molecular landscape, there is no a direct relationship with a specific gene, but a combination of genetic events. A broad spectrum of activated oncogenes and downregulated suppressor genes has been already explored and considered crucial for its progressive pathogenesis. Mechanisms of gene deregulation include amplifications, point mutations, allelic losses and also epigenetic abnormalities such as aberrant promoter methylation. Although a significant progress in understanding the molecular nature of the OS has been achieved, its aggressive phenotype - characterized by high metastatic potential - remains unexplored. Novel targeted therapeutic strategies include monoclonal antibodies (mABs) and also tyrosine-kinase inhibitors (TKIs). Additionally, sophisticated and innovative diagnostic techniques, such as 18 fluorodeoxyglucose positron emission tomography plus CT (18F-FDG/PET/CT), provide critical data regarding its biological behavior. In the current paper, we present novel molecular and metabolic advances by analyzing OS genetic profile and biochemical microenvironment.