Search

Immunohistokemi (IHK) är en metod som används för att undersöka närvaron av specifika biomarkörer i vävnad. Metoden utnyttjar antikroppars affinitet till antigen och dess närvaro visualiseras. Caldesmon är ett protein associerat med cytoskelettet som förekommer i glatta muskelceller och i icke-muskelceller. Det används inom IHK som en glatt muskelmarkör men även som en markör för myoepiteliet. Syftet med studien var att utveckla ett nytt protokoll för caldesmon och att jämföra den med SMMS-1, även den en markör för glatt muskulatur och myoepiteliet. Jämförelsen utfördes på fibroadenom vävnad, en bröstcancerform som utvecklats ur epitelialvävnad och stroma, då den innehåller mycket myoepitelial celler. För att effektivisera processen användes tissue microarray tekniken, där vävnad från flera olika preparat (klotsar) stansades ut och sammanfördes till en ny klots. Instrumentet Ventana Benchmark Ultra användes för att utveckla ett nytt protokoll för caldesmon. Det nya protokollet användes sedan vid jämförelsen med SMMS-1. Resultatet visade att SMMS-1 gav en tydligare infärgning av det myoepiteliala lagret då det enbart färgade in det, medan caldesmon även färgade in stroma. Då fibroadenom vävnad innehöll mycket stroma var det svårare att urskilja det myoepiteliala lagret från dess omgivning med caldesmon infärgningen., Immunohistochemistry (IHC), is a method used for examining the presence of specific biomarkers in tissue. It uses antibodies affinity for antigens and their presence can then be visualized. Caldesmon is a protein that is associated with the cytoskeleton in smooth muscle and non-smooth muscle cells. It is used within IHC as a marker for smooth muscle but also as a marker for the myoepithelium. The intent of this study was to develop a new protocol for caldesmon and to compare it with SMMS-1, also a marker for smooth muscle and the myoepithelium. The comparison was performed on tissue from fibroadenoma, a type of breast cancer that evolved from epithelial tissue and stroma, due to its high content of myoepithelial cells. For optimal effectiveness, the tissue microarray technique was used, where tissue from several blocks are extracted and brought together into a single new block. A Ventana Benchmark Ultra was used to develop a new protocol for the new antibody, caldesmon. The new protocol was used in the comparison with SMMS-1 on fibroadenoma tissue. The results were that SMMS-1 had a clearer and sharper staining of the myoepithelial layer, due to the fact that it only stained the layer. While caldesmon also stained the stroma in the tissue. Because fibroadenom tissue contained so much stroma the staining done with caldesmon made it harder to separate the myoepithelial layer from its surroundings.

Tamoxifen therapy resistance constitutes a major cause of death in patients with recurrent estrogen receptor (ER) positive breast cancer. Through high resolution mass spectrometry (MS), we previously generated a 4-protein predictive signature for tamoxifen therapy outcome in recurrent breast cancer. ANXA1 and CALD1, which were not included in the classifier, were however the most differentially expressed proteins. We first evaluated the clinical relevance of these markers in our MS cohort, followed by immunohistochemical (IHC) staining on an independent set of tumors incorporated in a tissue microarray (TMA) and regression analysis in relation to time to progression (TTP), clinical benefit and objective response. In order to assess which mechanisms ANXA1 and CALD1 might been involved in, we performed Ingenuity pathway analysis (IPA) on ANXA1 and CALD1 correlated proteins in our MS cohort. ANXA1 (Hazard ratio [HR] = 1.83; 95% confidence interval [CI]: 1.22-2.75; P = 0.003) and CALD1 (HR = 1.57; 95% CI: 1.04-2.36; P = 0.039) based patient stratification showed significant association to TTP, while IHC staining on TMA showed that both ANXA1 (HR = 1.82; 95% CI: 1.12-3.00; P = 0.016) and CALD1 (HR = 2.29; 95% CI: 1.40-3.75; P = 0.001) expression was associated with shorter TTP independently of traditional predictive fac

Prostaglandin E(1) (PGE(1)) lowers dermal interstitial fluid pressure (IFP) in vivo and inhibits fibroblast-mediated collagen gel contraction in vitro. PDGF-BB, in contrast, stimulates contraction and normalizes IFP lowered as a result of anaphylaxis. Human diploid AG1518 fibroblasts expressed EP2, EP3 and IP prostaglandin receptors. The inhibitory effect of PGE(1) on contraction depended on cAMP. Short-term stimulation with PDGF-BB transiently induced formation of actin-containing membrane and circular ruffles and breakdown of stress fibers. PGE(1) had no effect on stress fibers nor did it modulate the effects of PDGF-BB. PGE(1) alone or in combination with PDGF-BB inhibited initial adhesion and spreading to collagen. PDGF-BB had no effect on adhesion but stimulated cell spreading. Two-dimensional gel electrophoresis and MALDI TOF analyses of SDS/Triton X-100-soluble proteins revealed changes in migration pattern of actin-binding proteins. Interestingly, PDGF-BB and PGE(1) affected both similar and different sets of actin-binding proteins. PDGF-BB and PGE(1) did not trans-modulate their respective effects on actin-binding proteins, cytoskeletal organization or initial adhesion. Our data show that PDGF-BB stimulates actin cytoskeleton dynamics, whereas PGE(1) inhibits processes dependent on cytoskeletal motor functions. We suggest that these different activities may partly explain the contrasting effects of PGE(1) and PDGF-BB on contraction and IFP.

The ability of a tumor cell to grow outside its local environment (metastasize) is a major problem in the development and therapeutic treatment of breast cancer. The loss of the requirement for cell-matrix interactions plays a critical role in the development of cancer. Normal epithelial cells require attachment to the extracellular matrix (ECM) not only for proliferation but also for survival, as disruption of cell-ECM interactions can result in reversible cell growth arrest and induction of apoptosis, a phenomenon termed 'anoikis'. Elucidating the mechanisms by which the interactions of cells with the ECM generate and regulate downstream signals that promote cell growth and survival is critical to understanding cancer. Activation of actomyosin contractility is an essential Step during adhesion-dependent signaling. We are studying the role of specific components of the actin cytoskeleton whose expression have been implicated in the transformed phenotype. These studies will provide important new information concerning the role of these actin filament-associated proteins in adhesion-dependent cell signaling and the potential of inhibiting signal transduction pathways dependent on actomyosin contractility as a therapeutic target and adjuvant for the treatment of breast cancer, as well as other cancers.