Development of laboratory Development of laboratory models to study Breast Cancermodels to study Breast Cancer

Deborah Holliday

Breast Research GroupSection of Pathology & Tumour Biology

Section of Pathology and Tumour Biology

OutlineOutline

Introduction to the cells found in breast tissue

Changes in breast cells during breast cancer

Designing a model of breast cancermethods

Use of the model: A tool for looking at cancer progression

Cellular components of the normal breastCellular 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

Fibroblasts

Myoepithelialcells

Tumourcells

Luminal cells

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 tissueOrdered structure of the tissue is lost

Breast Cancer ProgressionBreast Cancer Progression

Pre-invasive breast cancer: Ductal Pre-invasive breast cancer: Ductal carcinoma in situcarcinoma in situ (DCIS)(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

Problems with treatment of DCISProblems 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

Important to define which DCIS cases Important to define which DCIS cases are likely to progressare likely to progressA better understanding of the biology A better understanding of the biology of tumour invasion may reveal new of tumour invasion may reveal new targets for therapiestargets for therapies

Designing a human model of breast cancerDesigning 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.

MethodsMethods

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.

Luminal cells

Fibroblasts

Collagen I

Culture media

Myoepithelialcells

Results

F

B

Day 1 Day 3 Day 5 Day 7

Blue: Tumour cells Red: Myoepithelial cells Green: Normal Fibroblasts

Green: Tumour Fibroblasts

Ductal carcinoma in situ (DCIS)

Invasive breast Carcinoma

Quantifying the modelQuantifying the model

0

1

2

3

4

5

6

7

8

9

10

lum/myo/Nfib mcf/myo/TAF

nu

mb

er o

f st

ruct

ure

s p

er f

ield

*

Normal Fibroblasts

Tumour Fibroblasts

Normal Fibroblasts

Tumour Fibroblasts

How we are using the model

• 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

• We have a model which we can use to study the biology of breast cancer

• This will help us understand how breast cancer progresses

Summary

Using 3D models to study radio-Using 3D models to study radio-resistance in Breast Cancerresistance in Breast Cancer

Laura Smith

Breast Research GroupSection of Pathology & Tumour Biology

Section of Pathology and Tumour Biology

Outline

Radiotherapy

Issues with radiotherapy

What would help overcome these issues?

The use of 3D models

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

Issues with Radiotherapy

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

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?

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?

Luminal cells

Treated Fibroblasts

Collagen I

Culture media

Myoepithelialcells

Use of 3D Models

Luminal cells

Untreated Fibroblasts

Collagen I

Culture media

Myoepithelialcells

Luminal cells Type II

Treated Fibroblasts

Collagen I

Culture media

Myoepithelialcells

Luminal cells Type I

Treated Fibroblasts

Collagen I

Culture media

Myoepithelialcells

Use of 3D Models

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