Follicular thyroid tumours: a study of laminin and type IV collagen in basement membrane and endothelium.

Abstract

SUMMARY Immunocytochemical stains for laminin and type IV collagen can be used as markers for basement membrane and vascular endothelium. Thirty four follicular thyroid lesions were examined using these techniques to investigate two aspects: firstly, the relation between the extent of invasion and the integrity of basement membrane; secondly, whether the techniques could enhance the detection of tumour vascular invasion. The results showed that although basement membrane was lost in widely invasive tumours, preservation was seen in most but not all encapsulated tumours. The potential for improved recognition of vascular invasion was also found.Well differentiated follicular thyroid tumours continue to pose diagnostic problems. The distinction between adenoma and follicular carcinoma can rest on subtle histological changes. For the patient the designation of benign or malignant tumour can have major implications. Treatment may range from lobectomy and reassurance to total thyroidectomy, thyroxine replacement, and the administration of radioactive iodine. Such difficulties have prompted investigation of many other possible discriminating features.Recently, attention has been focused on the role of basement membrane in the development of invasion. Loss of basement membrane was shown in invasive tumours in many sites.' 2 In the thyroid recent immunofluorescence investigations showed that loss of basement membrane may be found in follicular thyroid tumours.34 To investigate the diagnostic potential of this in more detail we examined a larger series of these tumours, using antisera to laminin and type IV collagen, both of which are components of the basement membrane.56 The use of these techniques to enhance the detection of tumour vascular invasion was also shown recently.7 As vascular invasion by follicular thyroid tumours is considered to be of particular diagnostic importance, and present additional methods for enhancing the detection of vascular invasion are unhelpful, this aspect was also examined.Accepted for publication 1 July 1985 Material and methods Thirty four follicular thyroid tumours were obtained from the files of the Leicester Royal Infirmary and the Leicester General .Hospital. After examination of sections stained with haematoxylin and eosin these were subdivided by degree of invasion. Twenty one cases showed no evidence of invasion, four showed early invasion of capsule or capsular vessels, and nine widespread invasion. Examples of normal and hyperplastic thyroid were also included. IMMUNOSTAININGThe tissues were routinely fixed in 10% formol saline for up to 48 hours and processed in paraffin.After dewaxing 5 ,um sections were treated for two hours with 0 4% pepsin in 0-01N hydrochloric acid (pH 2.0) at 37°C. The sections were then blocked for endogenous peroxidase activity using hydrogen peroxide in methanol. Immunostaining was performed with the peroxidase-antiperoxidase technique using laminin antiserum (1:50 dilution) followed by counterstaining with haematoxylin. The method was derived fro...

Galectin-3 and Laminin Expression in Neoplastic and Non-Neoplastic Thyroid Tissue

“…[42][43][44] To our knowledge, the consistent pericellular laminin deposition in anaplastic carcinomas which we observed in this study has not been previously reported. Although laminin is a natural ligand, we did not find a correlation between galectin-3 immunostaining and laminin expression.…”

Metalloproteinase-9 immunoexpression and angiogenesis in thyroid follicular neoplasms: Relation to clinical and histopathologic features

“…2 Recent oncologic literature has stressed the proteolytic action of some enzymes produced by neoplastic cells. 2 Recent oncologic literature has stressed the proteolytic action of some enzymes produced by neoplastic cells.…”

Higher Integrin Alpha 3 Beta1 Expression in Papillary Thyroid Cancer Is Associated with Worst Outcome

“…The α2β1 complex is the one with higher upregulation in thyroid carcinomas (up to 9-fold for ITGA2 vs. 2.5-fold for ITGA3 and ITGAV), although it is not the most abundant integrin expressed. This receptor, whose expression in benign and malignant thyroid tumors was previously detected by immunodetection, binds LM, COL, and heparan sulfate proteoglycan core protein, an integral component of the basement membrane [6,33]. Alpha 2β1 is over-expressed in a variety of cancer cells and experimental evidence suggest that its aberrant expression might contribute to invasion, metastasis, and drug resistance in non-small cell lung, ovarian, and breast cancer, pancreatic ductal adenocarcinoma, and hepatocellular carcinoma, being associated with poor survival in pancreatic ductal adenocarcinoma and potential therapeutic target for gastric cancer [35][36][37][38][39].…”

“…Invasive carcinomas generally show aberrant basement architecture and loss of LM around the epithelial structures [32]. Early thyroid immunohistochemical studies highlighted that adenomas and non-invasive FTC tend to preserve the basement membrane around the follicles while its partial or complete loss can be recognized in widely invasive FTC [33]. In contrast, PTC preserves basement membrane structure with abundant LM around the follicles [31].…”