Cancer Development and innate immune evasion
Tumor cells in order to thrive employ mechanisms that circumvent the immune response. This dynamic process is explained by the concept of cancer immunoediting, where some tumor cells variants have the capacity to escape the innate and adaptive immune system recognition, to then expand and hijack the host. However some tumor variants may protect less fit clones enabling immune evasion to then contribute to the whole tumor fitness, generating heterogeneous tumors with clones with different tumor traits. By combining live imaging, genetic and chemical tools we are studying the process of innate immune evasion and intra-tumoral clonal interactions using the zebrafish-larvae xenograft model. Understanding the process of innate immune rejection/ evasion may lead to new avenues of anti-cancer therapies based on modulating conserved innate immune mechanisms.

Zebrafish Avatars, towards personalised medicine
Despite advances in targeted cancer treatments, we still lack methods to predict how a specific cancer in a specific patient will respond to a given therapy. Consequently, patients go through rounds-of-trial-and-error approaches based on guidelines to find the best treatment, often subjected to unnecessary toxicity. We are developing zebrafish Patient Derived Xenografts (PDX) or “Avatars”, as sensors for cancer behavior and personalised therapy screening (Fior et al, PNAS 2017).

Zebrafish Avatars, towards personalised medicine

Despite advances in targeted cancer treatments, we still lack methods to predict how a specific cancer in a specific patient will respond to a given therapy. Consequently, patients go through rounds-of-trial-and-error approaches based on guidelines to find the best treatment, often subjected to unnecessary toxicity. We are developing zebrafish-larvae-xenografts as sensors for cancer behavior and personalized therapy screening. The test is based on the injection of tumor cells from patients into zebrafish larvae to then test which is the best therapy for that particular patient, within the available approved therapeutic options. Our data not only shows sufficient resolution to distinguish functional tumor behaviors in just 4-days, but also differential sensitivity to colorectal cancer therapies. As proof-of-principle experiments, in this study we provide evidence for a similar response to therapy in patients and their corresponding Zebrafish Avatars. Now we have recently expanded our assay to screen also Radiotherapy response (Costa et al, Ebiomedicine 2019).
Altogether, our results suggest zebrafish-larvae-xenografts as a promising in vivo screening platform for personalised medicine (Fior et al, PNAS 2017, Costa et al, Ebiomedicine 2019).

In collaboration with Champalimaud Clinical Centre and the Hospital Amadora Sintra, we have started 2 clinical studies: one in CRC and another in Breast cancer, to test the predictiveness of this assay by comparing the therapeutic response obtained in patients with its matching zebrafish PDX/ Avatars in many patients to further validate the model.

Colaborators: Champalimaud Clinical Centre (GI Unit, Breast Unit, Radiotherapy Unit, Urology Unit, GY Unit) and the Hospital Prof. Fernando Fonseca (Amadora Sintra)

Funding: FCT-PTDC/MEC-ONC/31627/2017 and Champalimaud Foundation

To escape or not to escape innate immunity

Immunotherapy is a revolutionary approach to cancer treatment. However, many patients do not respond and the potential for serious side effects exists. Therapy often fails because tumor cells are not recognized (they turn invisible) or because of other immune suppressive mechanisms in the tumor microenvironment (TME) that further block therapy. To generate more effective responses to checkpoint immunotherapy it is critical to select patients that will benefit from therapy (the right patients) but also discover new compounds that can help fully unleash the immune response i.e or take out the “invisibility cloak” or block the other suppressive mechanisms that avoid the “good cops” from acting. Fior recently developed zebrafish Patient Derived Xenografts (zPDX) “Avatars” to perform a quick in vivo screen for personalized chemotherapy. During this work Fior uncovered an intricate and intriguing communication between tumor cells and zebrafish innate. Some human tumors can induce a suppressive TME, that blocks tumor rejection allowing tumors to thrive and progress whereas other tumor cells get rejected by the zebrafish innate immune cells (neutrophils and macrophages). This rejection occurs in just 4 days and tumor cells are completely wiped-out from the host. By taking advantage of this unique model the Fior Lab is focusing on understanding the molecular players involved in this rejection/ suppression process and discover new therapies to be combined with adaptive immunotherapy. Finally, another goal is to test if zebrafish “Avatars” can be used to select patients for immunotherapy.

Funding: Terry-Fox Liga Portuguesa Contra o Cancro (LPCC) and Prémio Crioestaminal

Zebrafish Avatar for CLL Therapy Screening

Chronic lymphocytic leukemia (CLL) is the most common leukemia in western countries, typically occurs in elderly patients and has a variable clinical course. Leukemic transformation is initiated by specific genomic alterations that impair apoptosis. New drugs were approved for the treatment of CLL, such as specific inhibitors targeting pathways involved in cell survival (ibrutinib, idelalisib, and venetoclax). The international recommendations on CLL treatment in case of loss of the gene TP53, which gives the patient a very dismal prognosis, include these last options as match possibilities. No biomarkers were identified to guide the choice of treatment for each individual patient and treatments are selected based on the drugs’ toxicity profile and patients’ comorbidities rather than tumor sensitivity. Often the patient is treated with some of these expensive drugs in sequence, being exposed to unnecessary toxicity. By pre-testing tumor cells’ sensitivity to the available drugs, we believe that tailored therapy would avoid unnecessary toxicities and costs and would have a significant impact on the patients’ quality of life and healthcare systems. In this project, we will explore the zebrafish Avatar model to determine in vivo differential sensitivity of patient-derived CLL cells to novel drugs available. We will compare patient response to treatment to their matching zPDX. If this project proves successful we will have developed a new in vivo screening platform for CLL, possibly extensive to other lymphoproliferative diseases.

Colaborators: Cristina João – Myeloma Lymphoma Research Programme - Hemato-Oncologia

Funding: Kickstarter Grant -CF

Rita Fior, PhD
Research Associate
rita.fior@neuro.fchampalimaud.org

Biography

Ana Logrado

ana.logrado@neuro.fchampalimaud.org

Cátia Almeida
Research Technician
catia.almeida@research.fchampalimaud.org

Marta Estrada, PhD
Postdoctoral Researcher
marta.estrada@research.fchampalimaud.org

Mayra Martinez
External PhD Student
mayra.martinez@research.fchampalimaud.org

PhD Student

Vanda Póvoa
PhD Student
vanda.povoa@neuro.fchampalimaud.org

Costa B, Ferreira S, Póvoa V, Cardoso MJ, Vieira S, Stroom J, Fidalgo P, Rio-Tinto R, Figueiredo N, Parés O, Greco C, Ferreira MG and Fior R. (2019) Developments in zebrafish avatars as radiotherapy sensitivity reporters - towards personalized medicine.

R Fior (2019) Molecular and Cell Biology of Cancer: When Cells Break the Rules and Hijack Their Own Planet Springer

Povoa V, Fior R (2019) Cancer Immunoediting and Hijacking of the Immune System Springer

R Fior, R Zilhão (2019) Molecular and Cell Biology of Cancer: When Cells Break the Rules and Hijack Their Own Planet. Springer

Fior R* and Ferreira MG* (2018) Reply to Katsu and Baker: Using zebrafish PDX to screen drug sensitivity of endocrine-dependent cancers. Proc Natl Acad Sci U S A (doi:doi:10.1073/pnas.1802639115)

1. 2018 Fernandes S.F., Fior R., Pinto F., Gama-Carvalho M. and Saúde L. Fine-tuning of fgf8a expression through alternative polyadenylation has a selective impact on Fgf-associated developmental processes. BBA Gene Regulatory Mechanisms. Biochim Biophys (2018) Fine-tuning of fgf8a expression through alternative polyadenylation has a selective impact on Fgf-associated developmental processes. BBA Gene Regulatory Mechanisms. (doi: doi: 10.1016/j.bbagrm.2018.07.012. )

Fior R, Póvoa V, Mendes RV, Carvalho T, Gomes A, Figueiredo N, Ferreira MG. (2017) Single-cell functional and chemosensitive profiling of combinatorial colorectal therapy in zebrafish xenografts Proc Natl Acad Sci U S A PNAS 2017 September, 114 (39) , E8234-E8243 (doi: doi:10.1073/pnas.1618389114)

Lopes SS, Distel M, Linker C, Fior R, Monteiro R, Bianco IH, Portugues R, Strähle U, Saúde L. (2016) Report of the 4th European Zebrafish Principal Investigator Meeting. Zebrafish 2016 Dec;13 (6), 590-595 (doi:10.1089/zeb.2016.1364)

Fior R, Maxwell AA, Ma TP, Vezzaro A, Moens CB, Amacher SL, Lewis J, Saúde L. (2012) The differentiation and movement of presomitic mesoderm progenitor cells are controlled by Mesogenin 1 Development Dec;139(24): (139(24)), 4656-65 (doi:10.1242/dev.078923)

Cutty SJ, Fior R, Henriques PM, Saúde L, Wardle FC. (2012) Identification and expression analysis of two novel members of the Mesp family in zebrafish Int. J. Dev. Biol. 2012;56(4):285-94 (2012;56(4)), 285-94 (doi:10.1387/ijdb.113447sc.)

Fior R, Vilas-Boas F, Swedlow JR, Storey KG, Henrique D. (2011) A novel reporter of notch signalling indicates regulated and random Notch activation during vertebrate neurogenesis BMC Biol. Aug 31;9:58 (Aug 31;9:58), 9:58 (doi:10.1186/1741-7007-9-58)

Fior R, Henrique D. (2009) "Notch-Off": a perspective on the termination of Notch signalling. Int. J. Dev. Biol. 2009;53(8-10): (1379-84), 1379-84 (doi:10.1387/ijdb.072309rf)

Fior, R and Henrique D (2009) NOTCH-MATHICS American Mathematical Society & Real Sociedad Matemática Española

Fior R, Henrique D. (2005) A novel hes5/hes6 circuitry of negative regulation controls Notch activity during neurogenesis. Dev. Biol. 2005 May 15;281(2):318-33. (281(2):318-33.), 318-33. (doi:10.1016/j.ydbio.2005.03.017)