Establishment and characterization of ASPS-1 (AACR 2009)

[Olga]

David Vistica presented his new work on ASPS on the 2009 AACR Annual Meeting
April 18-22, 2009 Denver, CO in a Poster Session
Abstract Number: 4044
Session Title: Targets and Therapeutics in Pediatric Cancer 2
Presentation Title:
Establishment and characterization of ASPS-1, a novel cell line derived from metastatic alveolar soft part sarcoma

Author Block:
Susan Kenney, David T. Vistica, Luke Stockwin, Sandra Burkett, Melinda Hollingshead, Suzanne Borgel, David Schrump, Robert Shoemaker. NCI-Frederick, Frederick, MD, National Cancer Institute, Bethesda, MD

Investigation into the biology of Alveolar Soft Part Sarcoma (ASPS) and preclinical evaluation of potential ASPS therapeutics have been severely hampered by the lack of both in vitro and in vivo models of this soft tissue sarcoma. Recently we have described an in vivo xenograft model of ASPS in sex-matched NOD.SCID\NCr mice. This model, established from a lymph node metastasis from a female patient, has maintained characteristics consistent with those of the original ASPS tumor for over 3 years. Characteristics studied include: (1) tumor histology and staining with Periodic Acid Schiff/Diastase, (2) the presence of the ASPL-TFE3 type 1 fusion transcript, (3) nuclear staining with antibodies to the ASPL-TFE3 type 1 fusion protein, (4) maintenance of the t(X;17)(p11;q25) translocation characteristic of ASPS, (5) stable expression of signature ASPS gene transcripts and finally, the development and maintenance of a functional vascular network, a hallmark of ASPS. Utilizing this ASPS xenografted tumor we have successfully developed the first cell line of this rare pediatric sarcoma. Organoid nests consisting of 15-25 ASPS cells were isolated from ASPS xenograft tumors by capture on 70 um filters and plated in vitro. Following attachment to the substratum, these nests deposited small aggregates of ASPS cells. Over a period of 1.5 years, these cells were expanded and monitored for the following: ASPL-TFE3 type 1 fusion transcript, the t(X;17)(p11;q25) translocation and expression of up regulated ASPS transcripts involved in angiogenesis (ANGPTL2, HIF1 alpha, MDK, MET,VEGF, TIMP-2) , cell proliferation (PRL, PCSK1, IGFBP1), metastasis (ADAM9) as well as the transcription factor BHLHB3 and the muscle specific transcripts TRIM63 and ITGB1BP3. This ASPS cell line forms colonies in soft agar and retains the ability to produce highly vascularized ASPS tumors in NOD.SCID\NCr mice. Immunohistochemistry of selected ASPS markers on these tumors indicated similarity to those of the original patient tumor as well as to xenografted ASPS tumors. This ASPS cell line will facilitate investigation into the biology of ASPS and aid in the pre-clinical identification of new ASPS therapeutics.