Download Ph.D. Student : Charlotte Aaberg-Jessen Enrolment : 1 june 2009

Ph.D. Student
Enrolment
Project Title
Supervisors
Institute
Research Unit
: Charlotte Aaberg-Jessen
: 1 june 2009
: TIMP-1 in gliomas: prognostic and therapeutic potential?
: Bjarne Winther Kristensen, Henrik Daa Schrøder and Nils Brünner
: Institute of Clinical Research
: Pathology
Abstract:
TIMP-1 and the TIMP-1 interacting cell surface protein CD63 in cultured astrocytoma derived
spheroids: expression and co-expression with stem cell markers
Charlotte Aaberg-Jessen, Stine Skov Jensen, Henrik Daa Schrøder, Claus Andersen, Nils Brünner,
Bjarne Winther Kristensen
In previous studies we have shown that the immunohistochemical expression of TIMP-1 (tissue
inhibitor of metalloproteinases-1) and CD63 increases with tumor grade in astrocytomas grade IIIV. Moreover, we demonstrated that a high TIMP-1 protein expression in glioblastomas was
associated with a shorter overall patient survival. Recent studies have suggested that TIMP-1 can
prevent chemo-induced apoptosis and in a study, using human breast epithelial cells (MCF10A), it
was demonstrated that the interaction of TIMP-1 and CD63 is necessary for the TIMP-1 antiapoptotic pathway. The aim of the present study was to investigate the expression of TIMP-1 and
CD63 in cultured organotypic multicellular spheroids (OMS) and cell line spheroids (CLS) derived
from astrocytomas in order to assess spheroid models for future studies involving TIMP-1, CD63
and chemo-resistance. By investigating the spheroids immunohistochemically, we wanted to
elucidate if TIMP-1 and CD63 are co-expressed within the spheroids and whether they are
expressed by tumor stem like-cells, since these cells are known to be more resistant to
chemotherapeutic treatment. In the present study OMS from nine astrocytomas and CLS from three
commercial astrocytoma cell lines were included as well as the glioblastoma tumor stem cell line
SJ-1 made in our laboratory. In general high levels of CD63 protein was detected in all the original
tumors, whereas TIMP-1 was moderately expressed. TIMP-1 and CD63 expression in OMS was
similar to the expression in the original tumors. TIMP-1 was expressed at low to moderate levels in
CLS, whereas CD63 was expressed by all tumor cells in all spheroids. TIMP-1/CD63 double
immunofluorescence staining was performed on selected OMS and CLS showing tumor cells
expressing both proteins. Furthermore, double staining was performed with TIMP-1 and the stem
cell markers CD133 and Sox2 demonstrating that a population of the tumor stem like-cells
expressed TIMP-1. In conclusion, this study shows that spheroid models can be used in future
studies investigating the role of TIMP-1 and CD63 in chemo-induced apoptosis. Furthermore, these
results indicate that a fraction of the tumor stem like-cells could be protected by TIMP-1/CD63
interaction.
Keywords: Neuroscience, Oncology and Haematology