MO 04. HER 2 Status INFLUENCES SURVIVAL In the RAT MODEL OF BRAIN METASTASIS FROM BREAST CANCER M. A. Hunt,1 L. L. Muldoon,1 D. Palmieri,one P. S. Steeg,1 and E. A. Neuwelt1,2, 1Womens Cancers Part, Laboratory of Molecular Pharmacology, Center for Cancer Investigate, Nationwide Cancer Institute, Bethesda, MD, USA, 2Oregon Wellbeing Sciences University, Portland, OR, USA, and 3Portland VA Healthcare Center, Portland, OR, USA Brain metastasis develops in 20% to 40% of individuals with breast cancer. HER two good standing has been implicated in poorer prognosis from breast cancer and has also been connected with an increasing incidence of brain metastasis. The human MDA MB 231BR brain looking for breast carcinoma cell line was used in this experiment. Two subclones of this cell line have been previously made by transfection to express either low or large levels of HER 2 expression.
Eight nude rats had been sedated and underwent stereotactic implantation of both the native 231BR cell line, the large HER 2 expressing subclone, or the minimal HER two expressing cells. About 3. one 3 105 cells had been implanted into the basal ganglia. The rats had been followed for survival and have been provided more bonuses regimen examinations. When the rats became moribund, or demonstrated a significant neurologic deficit or severe excess weight loss, they have been sacrificed and their brains were collected for pathologic examination. Tumor volumes had been assessed after immuno histochemical staining with CAM5. two. The overall survival rate was assessed for statistical significance utilizing the Kruskal Wallis test. The suggest survival times for that native cell line, the minimal HER 2 expressing cell line, and the large HER 2 expressing cell line were 44 6 0 days, 36 six 0 days, and 19 6 1. 7 days, respectively. The distinctions in between all groups have been statistically vital.
Pathologic examination exposed sizeable, nicely cir cumscribed tumors during the parental 231BR cell line. The high GSK1838705A HER two tumors were smaller but had much more infiltrative margins. Our preliminary information sug gest that HER 2 standing correlates with decreased survival time inside a rat model of brain metastasis from breast cancer. More clones shall be examined. This model correlates with regarded clinical behavior of breast cancer and will permit evaluation of novel solutions for brain metastasis from breast cancer including combinations of trastuzumab with chemotherapy, and trastuzumab chemoimmunoconjugates. MO 05. GATA 6 Is a NOVEL ASTROCYTOMA TUMOR SUPPRESSOR GENE D. Kamnasaran,one C. Hawkins,one along with a. Guha1,two, 1Arthur Sonia Labatts Brain Tumor Centre, Hospital for Sick Children Investigate Institute, Toronto, 2Division of Neurosurgery, Western Hospital, University of Toronto, Canada Astrocytomas comprise in excess of 60% of all main human grownup central nervous technique neoplasms, and glioblastoma multiforme would be the most typical as well as the most malignant.