CANCER METASTASIS Leah Hogdal

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1 CANCER METASTASIS Leah Hogdal

2 Μετασταστασισ ( next placement ) Pancreatic cancer Metastatic pancreatic cancer of the lung/liver 90% of cancer deaths caused by metastasis (Mehlen & Puisieux, 2006)

3 Metastasis: a multitude of mutations. Fidler, 2003

4 Metastasis Organotropism Minn et al: Identify genes that are necessary for breast cancer metastasis to the lungs.

5 In vivo selection of breast cancer mets to the lung Minn et al. Nature (2005)

6 Lung-metastasis signature (LMS) Minn et al. Nature (2005)

7 Functional validation of LMS 49-fold increased expression in LM2 cell lines Knock-down associated with decreased metastasis Overexpressed in brain, pancreatic, ovarian and breast cancer

8 IL-13 signaling TH2?

9 IL-13Rα2 and cancer sirna of IL13Ra2 increases survival of mice with pancreatic cancer mirna KO of IL13Ra2 increases survival of mice with brain cancer KO of IL13ra2 decreases breast cancer metastasis Fujisawa et al Saka et al Minn et al The role of IL-13Ra2 expression and signalling in breast cancer metastasis is still unknown

10 Hypothesis: Signaling through IL-13Rα2 promotes the metastatic progression of breast cancer Aim1: To determine whether the overexpression of IL-13Ra2 is necessary for the metastatic breast cancer phenotype Aim 2: To determine if signaling through IL-13Rα2 promotes breast cancer cell invasion and protease activity Aim 3: To screen for and characterize novel factors involved in IL-13Ra2 signaling which mediate breast cancer metastasis

11 Aim 1: To determine whether the overexpression of IL-13Ra2 is necessary for the metastatic breast cancer phenotype Rationale: IL-13Ra2 is overexpressed in primary breast tumors, but it is known when and where overexpression occurs Models In vivo mouse model that overexpresses IL-13Ra2 Screen human patient samples for IL-13Ra2

12 BOM mouse model 1 wk 8 wk MDA-MB-231 are now metastatic Wang et. al 2009

13 Aim 1. Is IL-13Ra2 necessary for breast cancer metastasis Samples: 1. Implant human mammary tissue subcutaneously into 25 five week-old SCID mice. 2. Inject 5x10 6 GFP labeled MDA-MB-231 (5 mice) MDA-MB IL-13Ra2 (5 mice) LM (5 mice) LM shrna IL-13Ra2 (mice) Matrigel (5 mice) 3. Track tumor growth and metastasis with biolumenescence 4. Obtain tumor (primary and mets) and stain for IL-13Ra2 (IHC)

14 Mice with metastases Aim 1: Mouse model Potential results Matrigel MDA-231 MDA + IL13Ra2 LM2 LM2 + shrna Cells expressing IL-Ra2 will be highly metastic Cells not expressing the receptor will not metastasize

15 Aim 1. IL-13Ra2 necessary for breast cancer metastasis Human samples (with appropriate IRB credentials) 1. Obtain pre and post-metastatic primary site and metastatic site core biopsies 2. Embed biopsies in parafilm, section on slides 3. Stain sections with anti-il-13rα2 and counterstain 4. Quantify IHC intensities on periphery of epithelia

16 % of cells expressing IL-13Ra2 Aim 1: IL-13Ra2 necessary for breast cancer metastasis Potential results 120 Primary breast tumor samples Pre-met primary Post-met primary site Met site Identify localization

17 Aim 2: To determine if signaling through IL-13Rα2 promotes breast cancer cell invasion and protease activity RationaleIL-13 induces invasion activity in pancreatic cancer cells in a IL-13Ra2 dependent manner Methods Invasion assay and Protease assay Using cell lines: MCF-7 (Negative control) MDA-MB-231 MDA IL13Rα2 LM LM sh-il13rα2 MDA-MB-468 (positive control) Stimulate cells with IL-13 Westernblot for MMP expression Using cell lines above

18 Invasive cells per field Aim 2: IL-13Rα2 and cancer cell invasion Invasion assay 80 Unstimulated +IL MCF-7 MDA-MB-231 LM2 (4180) LM2 shil13- Ra2 Transfected IL-13Ra2 MDA-MB-468 Cells that express IL13-Ra2 will have more invasion/protease activity

19 Aim 3: To screen for and identify novel genes involved in IL- 13Rα2 induced breast cancer metastasis Rationale?

20 Aim 3: To screen for and characterize novel factors involved in IL-13Ra2 signaling which promote metastasis Methods: Co-IP IL-13Rα2 in LM2 and MDA-MB-231 cells Followed by mass-spec bands of interest Validate GOIs involvement in metastatic pathway by KO in IL-13Ra2 expressing cells Use IL-13Ra2 mutants to determine mode of signaling Mutants: ie. no cytoplasmic tail, multiple tails Determine if mutants can induce metastasis Expression analysis of of MDA-231 and MDA IL13-Rα2 Validate hits in pathway via RNAi

21 Questions/Comments?

22 Discussion Questions Why would cancer cells metastasize one organ preferably to another? Why is the process of metastasis so difficult to study? What models (both in vitro and in vivo) could facilitate better simulation of human metastasis?