Membrane Hsp70 — a novel target for the isolation of circulating tumor cells after epithelial-to-mesenchymal transition

The presence of circulating tumor cells (CTCs) in the peripheral blood is a pre-requisite for progression, invasion, and metastatic spread of cancer. Consequently, the enumeration and molecular characterization of CTCs from the peripheral blood of patients with solid tumors before, during and after treatment serves as a valuable tool for categorizing disease, evaluating prognosis and for predicting and monitoring therapeutic responsiveness. Many of the techniques for isolating CTCs are based on the expression of epithelial cell surface adhesion molecule (EpCAM, CD326) on tumor cells. However, the transition of adherent epithelial cells to migratory mesenchymal cells (epithelial-to-mesenchymal transition, EMT)—an essential element of the metastatic process—is frequently associated with a loss of expression of epithelial cell markers, including EpCAM. A highly relevant proportion of mesenchymal CTCs cannot therefore be isolated using techniques that are based on the “capture” of cells expressing EpCAM. Herein, we provide evidence that a monoclonal antibody (mAb) directed against a membrane-bound form of Hsp70 (mHsp70)—cmHsp70.1—can be used for the isolation of viable CTCs from peripheral blood of tumor patients of different entities in a more quantitative manner. In contrast to EpCAM, the expression of mHsp70 remains stably upregulated on migratory, mesenchymal CTCs, metastases and cells that have been triggered to undergo EMT. Therefore, we propose that approaches for isolating CTCs based on the capture of cells that express mHsp70 using the cmHsp70.1 mAb are superior to those based on EpCAM expression

Inhibition of radiation induced migration of human head and neck squamous cell carcinoma cells by blocking of EGF receptor pathways

<p>Abstract</p> <p>Background</p> <p>Recently it has been shown that radiation induces migration of glioma cells and facilitates a further spread of tumor cells locally and systemically. The aim of this study was to evaluate whether radiotherapy induces migration in head and neck squamous cell carcinoma (HNSCC). A further aim was to investigate the effects of blocking the epidermal growth factor receptor (EGFR) and its downstream pathways (Raf/MEK/ERK, PI3K/Akt) on tumor cell migration in vitro.</p> <p>Methods</p> <p>Migration of tumor cells was assessed via a wound healing assay and proliferation by a MTT colorimeritric assay using 3 HNSCC cell lines (BHY, CAL-27, HN). The cells were treated with increasing doses of irradiation (2 Gy, 5 Gy, 8 Gy) in the presence or absence of EGF, EGFR-antagonist (AG1478) or inhibitors of the downstream pathways PI3K (LY294002), mTOR (rapamycin) and MEK1 (PD98059). Biochemical activation of EGFR and the downstream markers Akt and ERK were examined by Western blot analysis.</p> <p>Results</p> <p>In absence of stimulation or inhibition, increasing doses of irradiation induced a dose-dependent enhancement of migrating cells (p < 0.05 for the 3 HNSCC cell lines) and a decrease of cell proliferation (p < 0.05 for the 3 HNSCC cell lines). The inhibition of EGFR or the downstream pathways reduced cell migration significantly (almost all p < 0.05 for the 3 HNSCC cell lines). Stimulation of HNSCC cells with EGF caused a significant increase in migration (p < 0.05 for the 3 HNSCC cell lines). After irradiation alone a pronounced activation of EGFR was observed by Western blot analysis.</p> <p>Conclusion</p> <p>Our results demonstrate that the EGFR is involved in radiation induced migration of HNSCC cells. Therefore EGFR or the downstream pathways might be a target for the treatment of HNSCC to improve the efficacy of radiotherapy.</p

Sarkome der Schilddrüse - zwei klinische Beispiele einer sehr seltenen Entität

Einleitung: Während die Struma nodosa fast 30% der deutschen Bevölkerung betrifft, machen maligne Tumore der Schilddrüse nur 1% aller malignen Tumore aus. Sarkome der Schilddrüse sind innerhalb dieser Gruppe eine extrem seltene Entität mit ca. 1% und weltweit sind nur knapp 150 Patientenfälle in der Literatur beschrieben. Falldemonstration: Fall 1: Ein 80-jähriger männlicher Patient wurde 05/2016 vorstellig um seinen "bayerischen Kropf" abklären zu lassen, der in letzter Zeit gewachsen sei. Histologisch handelte es sich dabei dem um ein ausgedehntes, schlecht differenziertes Angiosarkom mit 5/21 positiven Lymphknoten, ECE +.Fall 2: Eine 82-jährige Patientin stellte sich 06/2016 mit einer rasch progredienten Raumforderung im Bereich der Schilddrüse vor, welche sonographisch und MRT-morphologisch lipomatös wirkte. Histologisch zeigte sich ein hochdifferenziertes Liposarkom mit MDM2-positiver Fish Analyse.Diskussion: Das 5-Jahres Überleben von Sarkomen des Kopf-Hals Bereiches ist in einer Fallserie mit 130 Patienten mit 50% angegeben und damit schlechter als bei Sarkomen der Extremitäten. Lokalrezidive sind häufig, je nach Entität auch eine Multiorganmetastasierung. Histologisch wie auch prognostisch sind Angiosarkome schwer von anaplastischen Schilddrüsenkarzinomen zu unterscheiden. Liposarkome zählen zu den Raritäten selbst unter den Schilddrüsensarkomen. In der englischsprachigen Literatur gibt es bisher nur 8 Fallbeispiele zu finden. Die Therapie der Wahl ist die komplette chirurgische Resektion mit adjuvanter oder neoadjuvanter Strahlentherapie ggfs. inklusive Chemotherapie.Der Erstautor gibt keinen Interessenkonflikt an