Inside Colon

Inside Colon 

Colorectal cancer (CRC) is one of the most common and lethal malignancies in Western countries. It is the third most frequently diagnosed cancer and the second cancer with the highest mortality rate in Europe. Importantly, an increase in CRC incidence in young adults (individuals below 50 years of age) has been observed in different parts of the world, such as the USA and Australia. CRC is one of the few cancers that can be prevented through regular screening. Screening is crucial because when found early, CRC is highly treatable. Therefore, building awareness is extremely important to increase screening rates and decrease mortality.

The colon is the home to trillions of bacteria and fungi, all making up your gut microbiome. These bacteria are essential for your everyday life, and we need many of them to survive. They contribute to digesting our food and harvesting nutrients, as well as fighting off infection and playing a role in our immune system. The gut microbiota has the ability to break down non-digestible substrates like dietary fibers. However, some microbes can have a detrimental effect as well, particularly if a tumor is present.

In the context of colon cancer prevention, the Molecular Disease Mechanisms Group (MDM) from the University of Luxembourg (UL) had organized the event “Discover the inside of your colon – Boosting cancer prevention (Inside Colon)”. This event gave the opportunity to the public to learn about the latest research on the principles of cancer development, as well as the potential role of the microbiome in tumor development.

"Inside Colon” has been supported by the Luxembourg National Research Fund (FNR) (PSP-Classic 16774070) and aimed to:

  • Share with the public the current knowledge on Colorectal cancer (CRC), focusing on the research “made in Luxembourg” and on the importance of the CRC sample collection. 
  • Engage in a dialogue about the importance of participating in screening programs, highlighting that in Luxembourg there is a national CRC screening program for men and women between 55 and 74 years old who are invited by mail to participate every two years. 
  • Discuss, in particular with high-school children, the risk factors, namely the importance of a healthy diet. Diet influences our gut microbiome, a key player in regulating many functions of the human body. 
  • Raising awareness on the prevention in CRC.

Click on the image below to watch and listen to an interview of Dr. Elisabeth Letellier on the topic.

Molecular Disease Mechanisms Research Projects

Here you will find a video about the main research activities of the MDM group.

  • Microbiome and CRC

It has been shown that dysbiosis, a state of pathological imbalance in the microbiome, is present in patients suffering from colorectal cancer (CRC). Accordingly, several microbiome studies identified specific bacteria being associated with CRC. Some of these bacteria were described to directly interact with cancer and immune cells of their host. Nevertheless, only a very low number of CRC-associated microbes have been studied for host-microbial interactions, thus the role of bacteria in the etiology of the disease remains unknown. In this project, we aim at studying CRC-associated bacteria and their role in colon cancer tumor initiation and progression. This approach should help addressing the question of whether microbes are cause or consequence of CRC and ultimately, might lead to the development of new therapeutic strategies for CRC treatment.

Supported by: FNR PRIDE MICROH Doctoral Training Unit project

PI: Elisabeth Letellier

  • Effects of environmental stress factors on colon cancer and its microenvironment

The tumor microenvironment (TME) has been shown to play an important role in tumor development, especially in cancer initiation and metastasis. Immune cells, the extracellular matrix, angiogenesis, hypoxia, all have been uncovered as vital determinants of tumor behavior and expansion. Amongst all these various microenvironmental players, cancer associated fibroblasts (CAFs) have been suggested to play a key role in tumor development. Within the present project, we would like to 1) understand the role CAFs in CRC, 2) identify and characterize different CAF subpopulations and 3) finally assess the importance of CAFs in therapy resistance. To address these questions, several analyses will be performed, amongst which single cell sequencing.

Supported by: FNR PRIDE Doctoral Training Unit project (CANBIO and CORE)

PI: Elisabeth Letellier and Serge Haan

  • Personalized drug treatments for colorectal cancer patients

Oncology research is currently moving towards a new era of precision medicine where therapeutic approaches are customized for the individual patient based on the individual genomic landscape as well as on environmental and lifestyle factors. Precision medicine has been fueled by the enormous progress in high-throughput sequencing methods, which enable clinicians to detect rapidly and by now affordably genetic aberrations. However, predicting successful anticancer therapy remains extremely challenging, mostly due to extensive inter- and intratumoral heterogeneity. In this context, several groups have recently demonstrated the importance to perform a drug screening approach directly on patient-derived cancer cells, which more precisely recapitulate the molecular properties of the disease. Over the past years, the MDM group has majorly focused on the development of 3D models, which are capable of restoring the architecture of solid tumors and are therefore more suitable for the development of effective therapeutic approaches. In the proposed project, we will leverage our 3D models and combine them with genetic analysis and personalized drug library screening, in order to set-up a pipeline which identifies efficient and novel drugs and drug combinations in a personalised way for CRC.

Supported by: FNR (MelColPFP) and Fondation Marie Jeanne & Edmond Schumacher

PI: Elisabeth Letellier

  • Biomarkers for CRC

Over the past years, our group has established, in collaboration with different hospitals within the country as well as with the Integrated Biobank of Luxembourg (IBBL) and the Laboratoire National de Santé (LNS), an ongoing collection of tumor tissue samples from CRC patients that accounts for over 150 high quality patient samples. This collection contains tumor tissue as well as normal counterparts and different other collection samples such as serum, plasma, hair, saliva and stool samples. For all patient samples, the clinical information as well as the molecular data belonging to them is accessible, and thus allows studying clinical parameters, ultimately leading to potential interesting translational findings.

There is an urgent need for novel diagnostic markers, as well as molecular determinants of clinical outcome, which allow for the targeted treatment of patients at risk of relapse. By using a variety of clinical resources including our CRC cohort, we have recently identified promising biomarkers. A patent now protects one of the identified gene signatures and we have obtained additional funding to translate the biomarker into the clinics. We continue using our generated datasets and tools to further identify biomarkers in CRC.

Supported by: FNR Proof of Concept Study (MyoRPROG)

PI: Elisabeth Letellier

Images from the Inside Colon event at Cactus Belle Etoile


Besides the main event the project is:

Promoting an Art and Science Competition for High-School Children

Art and Science intersect in multiple ways. Scientists regularly use art to share their knowledge with others and artists are often inspired by science. The scientific process like the art process is a creative one, furthermore artists like scientists question the world around them. We invited high-school students to participate in a Science and Art Competition during the 1st semester of the academic year 2022/23. Cancer and Diet are part of the high-school curricula, and we had an open competition where under one (or both) themes high-schoolers made an art piece (for example painting, sculpture, or video). A jury (that includes scientists and artists) had chosen the best artwork. The winner pieces had exhibited at the event “Inside Colon" in November at the Shopping Center “Belle Etoile” and had been awarded a prize.


First prize, «Jardinet aquatique», Laurène Zimmer, EIMLB

Second prize, Ganassin Ayoub & Lorenzo Amir, EIDE

Third prize, «Clothing collection», Giovanna Duarte, EIDE

Fourth prize, «Colon is in», Classe de 4GSO-3, Ecole Sainte-Anne

Fifth prize, «Defensive warriors», Andrii, Ieva, Liana, Mariia, Yelizieveta and Daniil, Lycée Michel Lucius


Sixty (60) artworks were submitted to the competition, the works were truly amazing. Below a sample of other of the participating works:

«The Link», Xavier Sousa Pacheco, EIDE

«FXCK CANCER», Leìo Mondloch, EIMLB

Anastasia Shramenko, EIMLB

Melissa Reis Cunha & Wiam El Hawly, EIDE

Developing communication materials 

Apart from the event, we have produced videos and a comic strip to communicate the research on CRC and raise awareness towards the prevention measures available.


Related links:




Inside Colon has the support of the FNR and is run in collaboration with:

-          Fondation Cancer

-          Ministry of Health

-          Belle Etoile Shopping Center


*** Support colon cancer research at the University of Luxembourg***

University of Luxembourg

IBAN: LU22 0019 2955 8077 5000


Major: Colon cancer research