Currently, five types of breast cancer (luminal A, luminal B, HER2 enriched, triple negative and claudin low) are diagnosed in the clinic on the basis of the expression of three classical biomarkers (Estrogen Receptor, Progesterone Receptor and the HER2 tyrosine kinase receptor) and the proliferation marker Ki67. However, it is widely acknowledged that some of these types, particularly the triple negative -which is defined on the basis of the lack of expression of the classical markers- are also heterogeneous and include different types of breast cancer (Foulkes et al,2010). In fact, a recent transcriptomic and genomic analysis of a large cohort of samples distinguished up ten types of breast cancer (Group et al., 2012). Furthermore, even the type of breast cancer considered more homogeneous, theHER2-positive, is likely composed of different subtypes, one of them characterized for the presence of constitutively active fragments of HER2 known as p95HER2 (Arribas, Baselga, Pedersen, & Parra-Palau, 2011).

While the treatment of triple negative breast cancers remains a challenge, targeted treatments for other breast cancers are available. For example, ER positive and HER2-positive breast cancers are treated with anti-hormone therapy of drugs targeting HER2. These targeted drugs have increased the survival of patients; however, frequently tumors show innate or acquired resistance. Another important issue in breast cancer is the local recurrence and/or the appearance of distant metastasis time after surgical removal of the primary tumors. Therefore, a current challenge is to unveil the mechanisms and factors behind drug resistance as well as tumor recurrence/metastasis and to design novel therapies or combinations to tackle them. On the other hand, the identification of high and low risk genes will improve Genetic Counseling and early diagnostic of this disease.

To tackle the above mentioned problems, i.e. better classification of breast cancers, development of novel therapies and identification of novel high and low risk genes, it is crucial to use high quality clinical samples with extensive clinical data on the corresponding tumors as well as appropriate experimental models. While sophisticated genetically modified mouse models have helped to unveil novel mechanisms and factors involved in cancer progression, they are genetically homogeneous and do not represent the genetic heterogeneity of human breast cancers. Patient derived xenografts have been shown to authentically reflect tumor pathology, growth, metastasis and disease outcome( DeRose et al., 2011). A proper combination of the above outlined experimental approaches would be considered in research activity program from the coordinated actions of the involved groups.

1. HER2-positive breast cancers.
   • Identification of mechanisms of resistance to anti-HER2 therapies.
   • Development of novel anti-HER2 therapies.
2. ER/PR positive breast cancers.
   • Identification of novel targets of hormonal response.
   • Development of novel therapies for resistant tumors.
3. Triple negative breast cancers.
   • Improvement of the classification of triple negative breast cancers.
   • Development of novel therapies.
4. Identification of novel breast cancer biomarkers.
5. Breast cancer stem cells and cellular plasticity.
   • Characterization of the cellular intratumoral heterogeneity.
   • Isolation and characterization of breast cancer stem cells.
6. Breast cancer metastasis and tumor microenvironment.
   • Identification of novel factors and mechanisms involved in the metastatic process.
   • Characterization of the contribution of the tumor microenvironment to breast cancer progression.
7. Identification of healthy individuals at risk of developing breast cancer.
   • Characterization of BRCA1 and BRCA2 rare genetic variant of uncertain clinical significance.
   • Identification and characterization of new breast cancer susceptibility genes in BRCAX families.
   • Develop a polygenic model of breast cancer susceptibility to estimate cancer risk in the general population.
8. Establishment of a repository of patient derived xenografts.

The groups that form part of the Breast Cancer Translational Research Program have a record of publications in the best journal of cancer research. In addition, the groups of the Program are funded with competitive national and international calls. Currently, there are several ongoing collaborations between the groups of the Program. It is expected that the implementation of this program will foster these collaborations and will generate new ones.

As it is evident from the description of the previous contributions of the groups that form the Breast Cancer Transational Research Program, innovation will be a crucial part of our future activities. The main goals of workpackages HER2-positive breast cancers, Hormone-dependent breast cancers, Triple negative tumors, Biomarkers and Breast Cancer Genetics and Genetic Counseling deal with a better diagnoses of breast cancer and with the development of better therapies, mostly by using combinations of currently already available therapies. Obviously, these objective have a profound innovative potential and all the groups of the program participate in at least one of the these workpackages. Thus, innovation is one of the main focuses of our program.

Several groups of the Program have previous experience in technology transfer. As specified in the corresponding section (FIVE PATENTS RELATED WITH THE PROGRAMME (YEARS 2009-2010-2011), two patent applications from our groups have been licensed and they are currently under exploitation (P 200801652 - ES 2342646 / US 12/479,035 – US 2009/0311262 by group of Joaquín Arribas; PCT/US2007/062936, by group of Atanasio Pandiella ).The institutions participating in the Breast Cancer Translational Research Program have the appropriate departments to secure a correct management of the intellectual properties generated by our groups.

The groups that form the Breast Cancer Translational Research Program have different areas of expertise representing all phases of translational research, from basic (biochemistry, genetics, molecular and cellular biology), to more translational (research performed mainly with breast cancer samples) to clinical (clinical trials in all phases) research.. It is worth mentioning that the Program is funded on solid grounds: the groups that form this program have a previous history of collaboration. Further, virtually all the groups currently collaborate in lines of research inc lose relationship with the workpackages of this program. Not only the accomplishment of the scientific objectives represents a great opportunity of consolidating and strengthening currently ongoing collaborations between our groups, it will also contribute to increase our knowledge on breast cancer, and reinforce the position of our country within the international breast cancer research community. It is expected that the strength of this program will serve to catapult different groups to participate in international consortiums, particularly within the European region.

The composition of the Program is very well balanced and each one of the phase of translational research has a sufficient critical mass. Although it could be considered that basic research in underrepresented with only two groups, it should be kept in mind that the main goal of the Program is the implementation of translational research (i.e. with an impact on breast cancer patients) and that we are less interested in the basic mechanisms of breast cancer progression.

The Breast Cancer Translational Research Program will be coordinated by Joaquín Arribas, who, in addition, will be a member of the executive board of the RTICC. The leaders of each WP will support the management assuring the internal organization of the different researchers involved in each WP from groups. The PIs of all participating groups will meet yearly to discuss the progress of the scientific activities. After this meeting all every WP leader will write a report that will be sent to the coordinator. The coordinator will consolidate the reports of all WP into a document describing the activities of the Program, which will be presented at the RTICC annual meeting. Added value of the research groups from the cooperative structure The scientific strategy of the Program will follow the following logic:

Inputs:

• Breast cancer cell lines
• Breast cancer samples from randomized clinical trials
• Mouse models of breast cancer
• Patient-Derived Breast Cancer Xenografts
• Genomic DNA and RNA from breast cancer patients and control samples
• Different areas of expertise that represent all the phases of translational research, from basic (biochemistry, genetics, molecular and cellular biology) to clinical (clinical trials in all phases) research

• Identification of factors and mechanisms responsible for resistances to anti-HER2 therapies.
• Characterization of novel genetically modified mouse breast cancer models.
• Characterization of the novel triple-negative subgroups.
• Identification of factors and mechanisms mediating breast cancer metastasis. Novel biomarkers of metastasis.
• Analysis of intra-tumor heterogeneity in breast cancer.
• Characterization of the relevance of breast cancer stem cells in breast cancer progression.
• Identification and characterization of new genetic variants conferring breast cancer risk.

• A catalogue of biomarkers arising from (1) oncogene amplifications, (2) tumour suppressor gene deletions and (3)fusion genes that can be readily translated into laboratory reagents (i.e., FISH probes).
• Novel therapies and combinations against different types of breast cancers.
• Novel biomarkers to predict metastatic risk/ metastatic colonization.
• Defining genetic alterations in breast tumors by NGS (next generation sequencing).
• Improved genetic counseling. Particular attention will be devoted to such outputs from the program since, in addition to their clinical value, they may offer economic returns.

One of the main strengths of this program is the solid translational background of most of the researchers. Clinical trials and various technical developments with impact in the clinic have been created in the past with contributions of our groups. An added value is the representation of the largest Spanish clinical research group on breast cancer (GEICAM) within the program. This will undoubtedly allow rapid translation of lab findings into the clinic, and will also offer a nucleus of high repute basic researchers which may help in solving clinical problems identified by oncologists.

One of the centers participating in this program (the Cancer Research Center in Salamanca) has established a core facility which is aimed at speeding up drug development. This Translational Oncopharmacology Unit was established in 2007 and gives support to various academia as well as pharma labs who wish to evaluate the action of novel drugs or drug combinations. The unit also offers the possibility to carry out specialized services on demand, and is expected to offer such possibility to groups belonging to the RTICC (not only those belonging to the breast cancer research program).

This project is aimed to improve:

• The treatment of HER2-positive breast cancer.
• Hormone-sensitive breast cancers.
• The classification and treatment of triple negative breast cancers.
• The knowledge on the mechanisms and factors that mediate breast cancer metastasis.
• To understand the role of intra-tumor heterogeneity and breast cancer stem-like cells in therapeutic responses in breast cancer.
• The selection of healthy women who can benefit from intensive screening programs, and/or prophylactic measures.
• Therefore, the outcome of this project is expected to have an impact on the, prevention, diagnosis and treatment of breast cancers.
• From the scientific outcome, it is expected the project will give rise to publications in the most relevant journals in the field. It will also increase the potential for technological transfer in patents as well as the collaborations between the different multidisciplinary groups.

Regarding technology transfer, as mentioned above, we have previous experience in tecnology transfer. Two patent applications from our groups have been licensed and they are currently under exploitation. The protection of the intellectual property generated as a result of the activity of the program will be handled by the institutions that form part of it.

As indicator for external evaluation, we suggest:

• Annual report on the activities of the program.
• Articles co-authored by components of two or more groups of the program. Evaluable articles should acknowledge specifically funding from the RTICC.
• Collaborative research proposals granted to two or groups of the program.
• Clinical trials with participation of components of two or more groups of the program.
• Patents co-invented by components of two or more groups of the program.

As for the time-frame, we suggest evaluation in the second and fourth years.