The current treatment of leiomyosarcoma (LMS), the most common form of sarcoma, involves ineffective systemic therapy that is based on a trial and error approach and on the assumption that tumors called """"""""LMS"""""""" form a homogenous group. Recent advances in other forms of cancer therapy have relied on recognizing targetable pathways that are active in subsets of cases and the use of drugs on those cases only. Currently, no such appreciation exists for LMS, and we propose that an effective treatment for LMS should be based on a rational, molecular sub-classification of these tumors. In a continuation of previous work, we will focus efforts our efforts on the study of the molecular subtypes in LMS that we recently discovered. In the first Aim we will establish molecular signatures for large numbers of LMS cases with detailed clinical follow-up from surgical pathology archives. To this end, we will use a novel technique (3SEQ) that we developed to allow gene expression profiling on mRNA isolated from formalin-fixed paraffin-embedded tissue (FFPET) through next generation sequencing. Using this approach, we will confirm and extend our initial molecular characterization of LMS subtypes. Furthermore we will determine the prognostic significance of the molecular subtypes, and identify subtype-specific oncogenic pathways.
We aim at discovering predictors for the response to commonly used chemotherapeutic drugs, and will identify molecular prognosticators for the development of metastases. 3SEQ will also be used to analyze undifferentiated pleomorphic sarcoma (UPS, aka MFH) to determine to which extent the molecular subtypes now recognized in LMS can be identified in this tumor.
In Aim 2 we will identify the genetic events that are unique to each subtype and that could represent potential therapeutic targets and additional diagnostic markers. To achieve this, we will perform paired-end whole transcriptome sequencing (RNA-Seq) on a representative set of LMS cases to identify the single nucleotide variants and fusion transcripts that are unique to each LMS subtype. These studies will lead to a better understanding of the molecular events that drive LMS oncogenesis, and will improve the ability of clinicians to better diagnose LMS. As an ultimate goal, this work will prognosticate LMS behavior in individual patients and could lead to a more rational choice of treatment options for this disease.

Public Health Relevance

The majority of leiomyosarcomas do not respond to existing chemotherapy regimens. Any improvement of leiomyosarcoma treatment relies on the identification of molecular subsets within this tumor type that differ in clinical behavior and that may display a differential response to treatment. In this grant we will develop a clinically robust classifier of molecular subtypes of leiomyosarcoma, improve outcome prediction, and identify novel potential treatment options for LMS.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Research Project (R01)
Project #
5R01CA112270-10
Application #
8617808
Study Section
Cancer Biomarkers Study Section (CBSS)
Program Officer
Thurin, Magdalena
Project Start
2004-12-01
Project End
2015-02-28
Budget Start
2014-03-01
Budget End
2015-02-28
Support Year
10
Fiscal Year
2014
Total Cost
$304,863
Indirect Cost
$114,323
Name
Stanford University
Department
Pathology
Type
Schools of Medicine
DUNS #
009214214
City
Stanford
State
CA
Country
United States
Zip Code
94305
Demicco, Elizabeth G; Boland, Genevieve M; Brewer Savannah, Kari J et al. (2015) Progressive loss of myogenic differentiation in leiomyosarcoma has prognostic value. Histopathology 66:627-38
Guo, Xiangqian; Forgó, Erna; van de Rijn, Matt (2015) Molecular subtyping of leiomyosarcoma with 3' end RNA sequencing. Genom Data 5:366-367
Guo, Xiangqian; Jo, Vickie Y; Mills, Anne M et al. (2015) Clinically Relevant Molecular Subtypes in Leiomyosarcoma. Clin Cancer Res 21:3501-11
Keire, Paul A; Bressler, Steven L; Lemire, Joan M et al. (2014) A role for versican in the development of leiomyosarcoma. J Biol Chem 289:34089-103
Weiskopf, Kipp; Ring, Aaron M; Ho, Chia Chi M et al. (2013) Engineered SIRP? variants as immunotherapeutic adjuvants to anticancer antibodies. Science 341:88-91
Straessler, Krystal M; Jones, Kevin B; Hu, Hao et al. (2013) Modeling clear cell sarcomagenesis in the mouse: cell of origin differentiation state impacts tumor characteristics. Cancer Cell 23:215-27
Edris, Badreddin; Willingham, Stephen; Weiskopf, Kipp et al. (2013) Use of a KIT-specific monoclonal antibody to bypass imatinib resistance in gastrointestinal stromal tumors. Oncoimmunology 2:e24452
Weiskopf, Kipp; Ring, Aaron M; Schnorr, Peter J et al. (2013) Improving macrophage responses to therapeutic antibodies by molecular engineering of SIRP? variants. Oncoimmunology 2:e25773
Edris, Badreddin; Willingham, Stephen B; Weiskopf, Kipp et al. (2013) Anti-KIT monoclonal antibody inhibits imatinib-resistant gastrointestinal stromal tumor growth. Proc Natl Acad Sci U S A 110:3501-6
Kelly, Lorna; Bryan, Kenneth; Kim, Su Young et al. (2013) Post-transcriptional dysregulation by miRNAs is implicated in the pathogenesis of gastrointestinal stromal tumor [GIST]. PLoS One 8:e64102

Showing the most recent 10 out of 29 publications