The long-term objective of this R21 proposal is to gain a better understanding of the deadly disease of metastatic renal cell carcinoma. Clear cell renal cell carcinoma (ccRCC) is the most common subtype of kidney cancer. Von Hippel Lindau (VHL) is a tumour suppressor that is lost in the majority of ccRCC cases. Loss of VHL stabilizes hypoxia-inducible factors (HIF-1?) protein and upregulates its functional activities. Using the CRISPR genome editing method, we deleted the VHL gene in the murine RENCA and human ACHN ccRCC line and generated novel metastatic ccRCC models. Intriguing findings from our models revealed that VHL gene deletion leads to epithelial mesenchymal transition (EMT) that showed dramatic changes in cell morphology, increased cell motility, and decreased in cell proliferation. Pure clones of VHL-null (VHL-KO) cells grew poorly in vivo. But renal tumors with admixture of VHL-KO and VHL-WT cells exhibited fulminant lung metastases. The outgrowth of lung metastases involves predominantly VHL-WT (non-EMT) cells, suggesting a cooperation between heterogeneous cells is needed for metastasis. This project will undertake major efforts to track down the cooperative interactions between VHL-KO and VHL-WT during in vivo tumor growth and metastasis in both the murine RENCA and human ACHN model. From our recent published study, we have identified HIF-1? and several of its downstream genes, such as periostin, to play key roles in RCC metastasis.
The second aim of this project will use the CRISPR genome editing to create compound deletion of VHL and HIF1? and VHL and periostin to verify their role in the metastatic process in cell culture and animal studies. In the third aim, we will examine the expression of VHL, HIF1? and periostin in primary and metastatic RCC clinical specimens to verify their role in RCC aggression and metastasis. Our goal is to gain insights into the molecular mechanism of metastasis which could lead to better treatments for this lethal disease.

Public Health Relevance

Metastatic disease is the lethal stage for many solid tumors but it remains poorly understood currently. The objective of this project is to gain further understanding of the metastatic process in RCC, which could clearly have a great impact for patients afflicted with RCC and other cancers. As our recent findings highlight a cooperation between heterogeneous tumor cells (EMT and non-EMT) are at play in metastasis, this project will undertake the tedious work to track down the molecular and cellular interactions in our metastatic RCC models in immunocompetent mice.

Agency
National Institute of Health (NIH)
Institute
National Cancer Institute (NCI)
Type
Exploratory/Developmental Grants (R21)
Project #
5R21CA216770-02
Application #
9604787
Study Section
Special Emphasis Panel (ZCA1)
Program Officer
Mckee, Tawnya C
Project Start
2017-12-01
Project End
2019-11-30
Budget Start
2018-12-01
Budget End
2019-11-30
Support Year
2
Fiscal Year
2019
Total Cost
Indirect Cost
Name
University of California Los Angeles
Department
Pharmacology
Type
Schools of Medicine
DUNS #
092530369
City
Los Angeles
State
CA
Country
United States
Zip Code
90095
Hu, Junhui; Schokrpur, Shiruyeh; Archang, Maani et al. (2018) A Non-integrating Lentiviral Approach Overcomes Cas9-Induced Immune Rejection to Establish an Immunocompetent Metastatic Renal Cancer Model. Mol Ther Methods Clin Dev 9:203-210