The loss of antigenicity in archival formalin-fixed paraffin-embedded (FFPE) tissue sections negatively affects both diagnostic histopathology and advanced molecular studies. The mechanisms underlying antigenicity loss in FFPE tissues remain unclear. The authors hypothesize that water is a crucial contributor to protein degradation and decrement of immunoreactivity in FFPE tissues. To test their hypothesis, they examined fixation time, processing time, and humidity of storage environment on protein integrity and antigenicity by immunohistochemistry, Western blotting, and protein extraction. This study revealed that inadequate tissue processing, resulting in retention of endogenous water in tissue sections, results in antigen degradation. Exposure to high humidity during storage results in significant protein degradation and reduced immunoreactivity, and the effects of storage humidity are temperature dependent. Slides stored under vacuum with desiccant do not protect against the effects of residual water from inadequate tissue processing. These results support that the presence of water, both endogenously and exogenously, plays a central role in antigenicity loss. Optimal tissue processing is essential. The parameters of optimal storage of unstained slides remain to be defined, as they are directly affected by preanalytic variables. Nevertheless, minimization of exposure to water is required for antigen preservation in FFPE tissue sections. This article contains online supplemental material at http://www.jhc.org . Please visit this article online to view these materials.
Integrins are considered the main cell-adhesion transmembrane receptors that play multifaceted roles as extracellular matrix (ECM)-cytoskeletal linkers and transducers in biochemical and mechanical signals between cells and their environment in a wide range of states in health and diseases. Integrin functions are dependable on a delicate balance between active and inactive status via multiple mechanisms, including protein-protein interactions, conformational changes, and trafficking. Due to their exposure on the cell surface and sensitivity to the molecular blockade, integrins have been investigated as pharmacological targets for nearly 40 years, but given the complexity of integrins and sometimes opposite characteristics, targeting integrin therapeutics has been a challenge. To date, only seven drugs targeting integrins have been successfully marketed, including abciximab, eptifibatide, tirofiban, natalizumab, vedolizumab, lifitegrast, and carotegrast. Currently, there are approximately 90 kinds of integrin-based therapeutic drugs or imaging agents in clinical studies, including small molecules, antibodies, synthetic mimic peptides, antibody–drug conjugates (ADCs), chimeric antigen receptor (CAR) T-cell therapy, imaging agents, etc. A serious lesson from past integrin drug discovery and research efforts is that successes rely on both a deep understanding of integrin-regulatory mechanisms and unmet clinical needs. Herein, we provide a systematic and complete review of all integrin family members and integrin-mediated downstream signal transduction to highlight ongoing efforts to develop new therapies/diagnoses from bench to clinic. In addition, we further discuss the trend of drug development, how to improve the success rate of clinical trials targeting integrin therapies, and the key points for clinical research, basic research, and translational research.
Expression of various S100 genes has been associated with clinically aggressive subtypes in a variety of different cancers. We hypothesized that S100A4 would be overexpressed in endometrial carcinoma compared to benign endometrium. Quantitative real-time RT-PCR (qRT-PCR) was used to quantify the mRNA level of S100A4 in benign endometrium (n ¼ 19), endometrioid adenocarcinoma (n ¼ 87), and non-endometrioid tumors (n ¼ 21). Immunohistochemistry was used to verify the results of qRT-PCR and to assess protein localization. Possible mechanisms of S100A4 gene regulation were also examined. S100A4 was overexpressed in the grade 3 endometrioid tumors, uterine papillary serous carcinoma, and uterine malignant mixed mü llerian tumor. Expression in grade 1 and grade 2 endometrioid tumors was comparable to that of normal endometrium, which was quite low. Expression was significantly higher in stage III and IV tumors compared with stage I. By immunohistochemistry, S100A4 was expressed in the tumor cell cytoplasm of poorly differentiated tumors, but was not detected in normal endometrial glandular epithelium. In benign endometrium, S100A4 expression was confined to stromal cells. S100A4 was not regulated by estrogen or progesterone, and its expression in tumors was not significantly correlated to estrogen receptor or progesterone receptor content. However, methylation of the S100A4 gene was detected in benign endometrium and grade 1 tumors with low S100A4 expression. In contrast, grade 3 endometrioid tumors with high S100A4 mRNA and protein expression showed no methylation of the gene. These methylation results were verified in endometrial cancer cell lines with differential baseline levels of S100A4 protein. These results suggest that hypomethylation is an important mechanism of regulating the expression of the S100A4 gene. These results support the emerging concept that hypomethylation may play a role in the upregulation of genes during later stages of tumorigenesis. Keywords: endometrial cancer; S100A gene family; S100A4; methylation Endometrial carcinoma is the most common malignant neoplasm of the female genital tract and the fourth most frequently diagnosed cancer in women, following cancers of the breast, lung, and colon. 1 On the basis of histological and clinical features, endometrial carcinoma has been classified into two types. 2-4 Type I tumors (approximately 80% of all endometrial carcinomas) are typically low-grade (grade 1 or grade 2) endometrioid adenocarcinoma, most of which are confined to the uterus and have a favorable prognosis. Type II tumors (approximately 20%) are comprised of uterine papillary serous carcinoma, malignant mixed mü llerian tumors, and clear cell carcinoma. The nature of high-grade (grade 3) endometrioid adenocarcinoma is more controversial, as a subset may behave more like the Type II tumors. Type II cancers are associated with extrauterine spread and carry a high mortality rate. Previous studies have documented interesting molecular differences between endometrioid and nonendometrioid ...
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
customersupport@researchsolutions.com
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
This site is protected by reCAPTCHA and the Google Privacy Policy and Terms of Service apply.
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.