Dr Mirjana Efremova

MSc, PhD
Group Leader
www.efremovalab.org/ Twitter
Research Focus

We are interested in understanding the cellular and molecular mechanisms that promote cancer cell plasticity and adaptation of tumour cells in metastatic niches and under therapeutic pressure. By using dynamic analyses of the tumour microenvironment and metastatic niche in human samples and preclinical models, in conjunction with single-cell omics, imaging and computational analyses, we aim to achieve a systems-level understanding of the molecular circuits and cellular crosstalk driving metastasis and therapy resistance.

Key Publications

Single-Cell RNA Sequencing Reveals a Dynamic Stromal Niche That Supports Tumor Growth. Cell Reports (2020) 31(7):107628. PMID: 32433953

CellPhoneDB: Inferring cell-cell communication from combined expression of multi-subunit receptor-ligand complexes. Nature Protocols (2020) 15(4):1484-1506. PMID: 32103204

Computational methods for single-cell omics across modalities. Nature Methods (2020) 17(1):14-17. PMID: 31907463

Single-cell reconstruction of the early maternal-fetal interface in humans. Nature (2018) 563(7731):347-353. PMID: 30429548

Major Funding
  • 2020-2023 - Barts Charity, Dissecting the molecular circuits driving metastasis in melanoma

We employ a multidisciplinary approach that integrates computational and experimental strategies. Through collaborations with clinicians and researchers, we have access to patient samples and preclinical models, focusing on melanoma, pancreatic and colorectal cancer. By integrating single-cell multi-omics data, imaging and computational methods, our lab aims to dissect the cancer cell intrinsic traits and cell-cell communication networks that promote metastasis and therapy resistance.

The main areas of focus are:

Cancer Cell Plasticity

Cancer cells maintain an intrinsic plasticity that allows them to reversibly change their phenotype in response to microenvironmental signals and switch between cellular states. Single-cell studies have revealed extensive transcriptional heterogeneity along with lineage mixing and plasticity in several cancer types. In metastases, cells co-opt developmental programs and are reset to an even more primitive differentiation state, mimicking organ formation to reinitiate growth in a new location.

Using patient samples and multi-omics single-cell and bulk data, we are investigating the genetic vs non-genetic tumour heterogeneity and the regulatory networks underlying plasticity and invasiveness during metastasis.

Cell-cell communication

There is a growing understanding that the metastatic microenvironment is crucial in enabling the growth of disseminated cancer cells. In addition to the tumour cell intrinsic plasticity, local niche factors from stromal and immune cells influence tumour cell phenotypes and likewise, distinct cancer phenotypes shape the tumour microenvironment.

Our aim is to understand how cancer cells adapt to the metastatic niche and how in turn, immune and stromal cells support tumour cell plasticity and metastasis formation.

Therapy Resistance

Accumulating evidence implicates phenotypic plasticity as a key mechanism towards development of resistance to both targeted and immunotherapy. We aim to understand the molecular and cellular mechanisms driving phenotypic transitions in therapy resistance. By characterising the repertoire of phenotypes present both prior to and after therapy exposure, we are investigating the phenotypic states that promote resistance and their therapeutic vulnerabilities.

Our overarching goal is to identify key targets that drive metastasis formation and therapy resistance and find potential therapeutic strategies that disrupt crucial tumour-microenvironment interactions.

Visit my laboratory website here.

Major Funding
  • 2020-2023 - Barts Charity, Dissecting the molecular circuits driving metastasis in melanoma
Recent Publications

Developmental cell programs are co-opted in inflammatory skin disease Reynolds G, Vegh P, Fletcher J et al. Science (2021) 371(7)

Skin dendritic cells in melanoma are key for successful checkpoint blockade therapy Prokopi A, Tripp CH, Tummers B et al. Journal for ImmunoTherapy of Cancer (2021) 9(7)

Inference of Ligand-Receptor Pairs from Single-Cell Transcriptomics Data. Efremova M, Vento-Tormo R Methods Mol Biol (2021) 2346(2) 1-10

Mapping Rora expression in resting and activated CD4+ T cells. Haim-Vilmovsky L, Henriksson J, Walker JA et al. PLoS One (2021) 16(2) e0251233

Single-cell sequencing reveals clonal expansions of pro-inflammatory synovial CD8 T cells expressing tissue-homing receptors in psoriatic arthritis Penkava F, Velasco-Herrera MDC, Young MD et al. Nature Communications (2020) 11(7)

P03.31 Skin dendritic cells in melanoma are key for successful checkpoint blockade therapy Prokopi N, Tripp C, Tummers B et al. Journal for ImmunoTherapy of Cancer (2020) 8(10) a35.2-a3a36

Mosquito cellular immunity at single-cell resolution Raddi G, Barletta ABF, Efremova M et al. Science (2020) 369(7) 1128-1132

Single-Cell RNA Sequencing Reveals a Dynamic Stromal Niche That Supports Tumor Growth Davidson S, Efremova M, Riedel A et al. Cell Reports (2020) 31(7)

Immunology in the Era of Single-Cell Technologies Efremova M, Vento-Tormo R, Park JE et al. Annual Review of Immunology (2020) 38(1) 727-757

CellPhoneDB: inferring cell–cell communication from combined expression of multi-subunit ligand–receptor complexes Efremova M, Vento-Tormo M, Teichmann SA et al. Nature Protocols (2020) 15(7) 1484-1506

For additional publications, please click here
During my PhD in Computational Biology in the lab of Prof Trajanoski at the Medical University of Innsbruck, Austria, I investigated the process of clonal evolution of cancer under immunosurveillance and how the immune system shapes tumour progression. For my postdoctoral research, I joined the Teichmann Lab (Wellcome Sanger Institute) where I co-led the development of the first human atlas of the maternal-fetal interface in early pregnancy using single cell transcriptomics. I also developed a cell-cell communication statistical framework CellPhoneDB (www.cellphonedb.org) for predicting enriched receptor-ligand pairs between the different cell types and inference of cellular communication networks. This framework allowed me to dissect the complex interplay between stromal and immune cells in the dynamic tumour microenvironment of a mouse melanoma model. In May 2020 I started my own lab at Barts Cancer Institute, Queen Mary University of London (UK) within the Centre for Cancer Genomics and Computational Biology.