Early diagnostic of cancers is crucial for patients and the success of their therapies. Finding a diagnostic index with high sensitivity at the early stage of cancers is a major concern. Invasive biopsies may be already too late and are certainly painful. Thus, the challenge is to find biomarkers from simple blood samples. Circulating microRNA are the best leads for such research. Let’s see why with a recent publication.

This year again, we were pleased to attend the Annual meeting of the AACR (American Association for Cancer Research), which took place in Washington DC, USA at the beginning of April.

Nadia Normand Ph.D. (Business Development Manager, tebu-bio), presented a poster with results from collaborative work between the Centre for Molecular Biophysics of the CNRS (Orléans, France), tebu-bio Laboratories (Le Perray en Yvelines, France), Anaxomics Biotech (Barcelona, Spain) and the Institute of Immunology and Experimental Therapy (Wroclaw, Poland).

This poster “miRNome analyses reveal that activity of CAF expressed podoplanin in the tumor microenvironment is modulated by exosome miRNAs involved in the PTEN-PI3K-AKT-mTOR signaling” is now available for downloading – get your copy here.

We need to find biomarkers for prognostic, diagnostic and personalised treatment development. Notably to fight cancers that affect tissues. Since biopsies are invasive, it’s better to look for biomarkers in body fluids. Indeed, a simple blood sample becomes a kind of ‘liquid biopsy’ to reveal tissues affections. For 13 years, increasing interest has been shown for miRNA as biomarkers and it will last for sure. The 2 main reasons are that they are major regulators of cell processes and they are released from tissues into the blood. They are major biomarker candidates in serum and plasma. Thus, these circulating miRNA (cmiRNA) are the best hope for modern medicine. Still, a lot of research has to be done to determine the specific signature for each pathology, and also depending on the patient background. Obviously, cmiRNA profiling is a key step and requires sensitive and reproducible method. Sequencing, qRT-PCR, several kind of microarrays… Let’s explore together what the best approach could be.

Source: Kumar M. et al. (DOI: http://dx.doi.org/10.1016/j.chom.2015.01.007).

The outcome of the interaction between Mycobacterium tuberculosis (Mtb) and a macrophage depends on the interplay between host defense and bacterial immune subversion mechanisms. MicroRNAs (miRNAs) critically regulate several host defense pathways, but their role in the Mtb-macrophage interplay remains unclear.

Recently, Kumar et al. performed a miRNA profiling, and investigated the downregulation of miR-let-7f in a manner dependent on the Mtb secreted effector ESAT-6.