Download Laser Capture Microdissection to Isolate Primary and

Poster No. 34
Title:
Laser Capture Microdissection to Isolate Primary and Metastatic Thyroid Tumors from Formalin Fixed
Paraffin Embedded Tissue
Authors:
Caroline Kim and Sheue-yann Cheng
Presented by:
Caroline Kim
Departments:
Division of Endocrinology and Molecular Oncology Research Institute, Tufts Medical Center
Abstract:
Identifying the determinants of thyroid cancer metastasis is often limited by tissue availability. Studies utilizing
a mouse model of follicular thyroid cancer (TRßPV mouse) which spontaneously develops thyroid cancer that
recapitulates human follicular thyroid cancer behavior, including lung metastases, have identified candidate
genes central for thyroid cancer tumorigenesis. Previous microarray analysis on TRßPV mice has not included
lung metastatic tumors1. Using archived formalin fixed paraffin embedded tissue blocks, we are isolating wildtype, primary thyroid tumors, and metastatic thyroid cancer to lung for eventual microarray analysis.
Laser capture microdissection (LCM) of wild-type thyroids, primary thyroid tumors at sites of capsular or
vascular invasion, and lung metastases was performed. RNA integrity for each tissue block was assessed by
comparing the 3’/5’ ratio of the housekeeping gene, ß-actin prior to LCM. As proof-of-principle, quantitative
real-time PCR was performed examining the expression level of a known upregulated gene in the thyroids of
TRßPV mice, PTTG1. Similar to previous reports, PTTG mRNA isolated from laser captured thyroid cancer of
TRßPV mice was expressed ~5-fold higher compared to the mRNA from age-matched wild-type thyroids.
These findings suggest that LCM of these archived tissue blocks is a viable approach to obtain RNA for
microarray analysis. Future studies will compare and contrast the gene expression profiles of primary versus
metastatic thyroid tumors that may identify novel contributors to thyroid cancer metastasis.
(1) Ying H., Suzuki H., Furumoto H., Walker R., Meltzer P., Willingham MC., Cheng SY. 2003 Alterations in
genomic profiles during tumor progression in a mouse model of follicular thyroid carcinoma. Carcinogenesis 24
(9):1467-79.
36