Development of laboratory models to study Breast Cancer

1. Section of Pathology and Tumour Biology Development of laboratory models to study Breast Cancer Deborah Holliday Breast Research Group Section of Pathology & Tumour Biology

2. Outline Introduction to the cells found in breast tissue Changes in breast cells during breast cancer Designing a model of breast cancer methods Use of the model: A tool for looking at cancer progression

3. Cellular components of the normal breast Luminal epithelial cells: Milk producing cells Hormone responsive ER-alpha positive cells Myoepithelial cells: Surround the luminal cells Contractile cells Luminal and Myoepithelial cells form the glandular unit of the breast Fibroblasts: Form the structural component of the surrounding breast tissue Produce proteins important for maintaining breast structure Other cell types Blood vessels, fat cells, inflammatory cells

4. ? Tumour cells Myoepithelial cells Luminal cells Fibroblasts Breast Cancer Progression • Normal breast tissue • Cells look ordered in appearance • Pre-invasive breast cancer • Tumour cells in the centre start to grow out of control • Invasive breast cancer • Tumour cells escape into the surrounding breast tissue • Ordered structure of the tissue is lost

5. Pre-invasive breast cancer: Ductal carcinoma in situ(DCIS) DCIS is characterised by confinement of tumour cells to the breast glandular unit DCIS accounts for 40% of screen detected breast carcinoma 25-30% of untreated DCIS will progress to invasive carcinoma

6. Important to define which DCIS cases are likely to progress A better understanding of the biology of tumour invasion may reveal new targets for therapies Problems with treatment of DCIS • Mastectomy • Patient is cured but ? Overtreatment ? • Conservative surgery • A proportion of tumours will recur • Some of those will progress to invasive carcinoma

7. Designing a human model of breast cancer • The model would need to include 3 major cell types involved in breast cancer: • Tumour cells. • Myoepithelial cells (protector cells). • Fibroblasts (tumour helper cells). • Cells would need to be grown in culture conditions which resemble those in the body: • Able to grow in 3 dimensions rather than on a plastic Petri dish. • Such a model would be a valuable tool: • To help us understand how breast cancer progresses. • To allow us to test new drugs for therapy. • To potentially identify new targets for future drug development.

8. Methods Myoepithelial cells Luminal cells Fibroblasts Collagen I Culture media • We isolated cells from normal breast tissue or from breast cancer tissue and grew then in a 3 dimensional matrix of collagen. • By labelling our cells with different colours we were able to identify the different cell types in our model. • We used the model to investigate whether fibroblasts are able to make pre-invasive lesions become invasive.

9. Day 1 • Day 3 • Day 5 • Day 7 Ductal carcinoma in situ (DCIS) Invasive breast Carcinoma Green: Tumour Fibroblasts Results B Blue: Tumour cells Red: Myoepithelial cells Green: Normal Fibroblasts F

10. Quantifying the model 10 9 8 7 6 5 number of structures per field 4 3 2 * 1 0 mcf/myo/TAF lum/myo/Nfib Normal Fibroblasts Normal Fibroblasts Tumour Fibroblasts Tumour Fibroblasts

11. Summary How we are using the model • We have a model which we can use to study the biology of breast cancer • This will help us understand how breast cancer progresses • Different tumour cells to represent different types of breast cancer • Different fibroblasts to understand why in some patients cancer progresses faster than in others • Include drugs into the model with tumour fibroblasts to see if we can prevent ‘invasion’ • Established drugs • New Drugs = pre-clinical drug screen

12. Section of Pathology and Tumour Biology Using 3D models to study radio-resistance in Breast Cancer Laura Smith Breast Research Group Section of Pathology & Tumour Biology

13. Outline • Radiotherapy • Issues with radiotherapy • What would help overcome these issues? • The use of 3D models

14. Radiotherapy • Reduces risk of the cancer coming back • Is given to many breast cancer patients • All patients having breast conserving surgery • Patients having a mastectomy but at high risk of the cancer coming back

15. Issues withRadiotherapy • Unpleasant side effects • Short term • Long term • Stressful regime • Daily hospital visits 5 days/ week for 3 weeks • Limited availability of treatment machines • Long waiting lists in some areas • Not all patients will benefit • Some patients cancer will come back anyway

16. Overcoming these issues • Better patient selection • Estrogen Receptor for Tamoxifen therapy • HER2 for Herceptin therapy • Nothing analogous to guide radiotherapy • Why do some cancers respond well to radiotherapy whilst others do not? • What factors are involved? • Radio-sensitizing drugs?

17. Our Study • It is not only cancer cells that are exposed to radiotherapy but also the fibroblasts • Do fibroblasts influence breast cancer cell response to radiotherapy? • Do fibroblasts differentially influence the response of different breast cancer types?

18. Myoepithelial Myoepithelial cells cells Luminal cells Luminal cells Treated Fibroblasts Untreated Fibroblasts Collagen I Collagen I Culture media Culture media Use of 3D Models

19. Myoepithelial cells Luminal cells Type II Myoepithelial cells Treated Fibroblasts Luminal cells Type I Collagen I Treated Fibroblasts Culture media Collagen I Culture media Use of 3D Models

20. Summary • Reduce side effects and improve quality of life for patients that will not benefit • Allow drs to select another type of treatment that will work for these patients • Reduce waiting times for those patients that will benefit thereby increasing survival