Layer Of Normal Epithelium Research Articles

Down-regulation of FA-BRCA Pathway in Cervical Carcinoma Gradually Reversed During the Development of Chemo-tolerance: Clinical Implications.

Cervical cancer is one of the leading causes of cancer death among females, worldwide. The contributory role of different cellular pathways in the process of carcinogenesis is still poorly understood. Our study was focused here to understand the functional evaluation of key regulatory genes of FA-BRCA pathway in the development of CACX and their role in chemo-tolerance of the disease by analyzing the molecular profile of the genes both in normal and tumour tissue of our sample pool, also validated in in silico datasets. Later on, prognostic importance of the genes was further evaluated in plasma DNA and cisplatin-treated in vitro system. We found that expression profile of FA-BRCA pathway genes was gradually reduced from undifferentiated basal-parabasal layers of normal tissue towards the progression of the disease. Further analysis revealed that frequent promoter methylation [32-55%] and deletion [34-52%] events were the plausible reasons for their reduced expression in CACX. Noticeably, invasion of promoter methylation of the genes [11-17%] in plasma CTCs of CACX patients was positively correlated [p < 0.001] with poor prognosis among patients. On the other hand, functional upregulation of these genes at higher concentrations [IC50-70] of cisplatin was a predictor for the development of drug tolerance, as evaluated in our in vitro study. This finding was supported further by low prevalence of γ-H2X foci formation and reduced expression of DNMT1 at higher concentrations of cisplatin. In totality, we discovered that the FA-BRCA pathway must be inactivated for cancer formation. In contrast, elevated gene expression played a substantial role in building of chemo-tolerance and might be associated with developing increased risk of disease recurrence among patients.

Abstract 6260: Identification of molecular imaging targets specific for head and neck squamous cell carcinoma by transcriptional adaptation to copy number alterations profiling: Digital data translated to protein expression

Abstract Objective: Head and neck squamous cell carcinoma (HNSCC) can intraoperatively be visualized by fluorescence molecular imaging (FMI) using fluorophores conjugated to HNSCC specific antibodies. Currently, the epidermal growth factor receptor (EGFR) is used as a target. Targets more specific for HNSCC would reduce background signal, resulting in a higher tumor to background ratio. We aimed to identify new potential targets for FMI in HNSCC. Methods: Publicly available transcriptomic data were collected. A biostatistical method known as Transcriptional Adaptation to Copy Number Alterations (TACNA) profiling was applied, which captures the downstream effects of copy number alterations (CNAs) on mRNA levels, which we used to predict the overexpression on the protein level. By comparing gene expression profiles of HNSCC and normal oral mucosa, genes overexpressed explicitly in HNSCC were identified. Potential targets were selected based on the degree of overexpression, plasma membrane expression, and cross expression in other tissues in the head and neck region. Next, the expression of potential targets of TACNA results on mRNA level were validated on the protein level and compared to EGFR expression using immunohistochemistry (IHC). Subsequently, paired biopsies of HNSCC, adjacent suspicious mucosa, and healthy mucosa of the same patients were stained. Receptor expression was evaluated using H-scores (i.e., percentage of positive cells combined with staining intensity). Results: TACNA profiling was applied on 111 samples of healthy oral mucosa and 410 HNSCC comparing expression levels of 19,635 genes. The newly identified membrane-bound targets were glucose transporter 1 (GLUT-1), placental cadherin (P-cadherin), and monocarboxylate transporter 1 (MCT-1). The three targets were evaluated by IHC in a total of 31 patients, of which 8 had oropharyngeal, 7 hypopharyngeal, and 16 laryngeal carcinomas. GLUT-1 had a median H-score of 175, P-cadherin 140, and MCT-1 40. GLUT-1 and P-cadherin were significantly higher compared to EGFR, with a median H-score of 90 (p &amp;lt; .001). GLUT-1 receptor expression was also seen on erythrocytes, while P-cadherin expression was seen in the basal layer of normal epithelium. This can complicate its use in FMI. Conclusion: TACNA profiling results were successfully validated in immunohistochemistry as a first step in the search for new specific FMI targets in HNSCC. GLUT-1 and P-cadherin show promising results with significantly higher receptor expression than EGFR. Citation Format: Jeroen E. van Schaik, Bert van der Vegt, Bernard F.A.M. van der Laan, Max J.H. Witjes, Sjoukje F. Oosting, Rudolf S. Fehrmann, Boudewijn E. Plaat. Identification of molecular imaging targets specific for head and neck squamous cell carcinoma by transcriptional adaptation to copy number alterations profiling: Digital data translated to protein expression [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 6260.

Endogenous lectins (galectins-1 and -3) as probes to detect differentiation-dependent alterations in human squamous cell carcinomas of the oropharynx and larynx.

Expression of glycan determinants for in situ binding is the prerequisite for a productive protein (lectin)-carbohydrate recognition. Labeled tissue lectins as tools are preferable to plant lectins to assess this parameter, because plant and animal lectins with identical saccharide specification can well differ in their profiles of oligosaccharide binding pattern. Due to their relevance in growth control and matrix adhesion the family of galectins (galactoside-binding metal ion independent animal lectins) is receiving increasing utilization in human biology. Employing biotinylated galectin-1 and galectin-3 we studied the expression of binding sites for these galectins in normal human squamous epithelium and human carcinomas from the oropharyngeal region and larynx in relation to the expression of LP-34+ cytokeratins by the procedure of double labeling. Tissue sites accessible for galectin-1 were located in all layers of normal epithelium and in tumor cells. In contrast, galectin-3 binding was suprabasal in the normal epithelium and in tumor cells exhibiting signs of keratinization. These results reveal differences in the localization of accessible sites for the two galectins. Relating to cell development galectin-3 appeared to display affinity to areas with increased extent of differentiation.

Antigen expression of epithelial markers, collagen IV and Ki67 in middle ear cholesteatoma. An immunohistochemical Study.

The expression of epithelial markers (cytokeratins, Filaggrin, BerEp4 and EMA), collagen IV and Ki67 was studied immunohistochemically in cholesteatoma and compared with that in epidermis of meatal skin, squamous epithelium of eardrum and simple epithelium of middle ear mucosa. MNF116 (cytokeratin 10, 17, 18) stained the full layer of normal epithelium and all cholesteatoma specimens. CK10 and Filaggrin were expressed in the upper layer of epidermis but more diffusely in cholesteatoma. BerEp4 was found in the basal layer of normal epithelium but was detected in most epithelial cells in cholesteatoma matrix. Variability was observed in EMA and CK14 immunostaining. Collagen IV was localized in the basement membrane of normal epithelium with a continuously staining pattern, an observation also made in the cholesteatomas studied. However, in one of these small areas the basement membrane was not stained with collagen IV. Ki67 was expressed in nuclei of the cells in the basal layer of normal epithelium but extended to epithelial cells in the upper layers of cholesteatoma matrix. The results of the present study indicate that the expression pattern of epithelial markers in cholesteatoma corresponds to that in normal epidermis. The increasing expression of BerEp4 and Ki67 confirms the hyperproliferative nature of cholesteatoma. Whether or not the lack of expression of collagen IV in one of the cholesteatomas reflects a true degradation of the basement membrane needs further investigation in extended materials.