Reacción a "Reactions to study that identifies cells responsible for colon cancer relapse "

The study carried out by Dr. Eduard Batlle's team is of very high quality. From the generation of murine models [in mice] of colon cancer and tumoroids derived from these, and using very advanced molecular biology techniques and next-generation sequencing techniques, they identify a population of tumor cells that they call HRC and that would be responsible for the appearance of metastasis. In order to track these cells and eliminate them, they identify the EMP1 protein as a marker to follow. Thus, using colorectal cancer tumor models in mice, they demonstrate that the elimination of this population of HRC cells makes the generation of metastasis disappear in mice.  In addition, they show that micrometastases, which are enriched in CRH cells, have a greater infiltration of T lymphocytes, suggesting that the use of immunotherapy in early stages could significantly improve the evolution of colon cancer patients.  

This work provides evidence, based on preclinical models, of the potential role that immunotherapy could have in the most common colorectal tumors, which are tumors with microsatellite stability where, so far, the use of immune checkpoint inhibitors (ICIs) has not shown clinical benefit. It is now known that these drugs are effective in the treatment of colorectal cancer with microsatellite instability, both in metastatic disease and in localized disease, as has recently been reported in studies with ICIs in neoadjuvant therapy (before surgery on the primary tumor). Following this line, and after the observations made in this work, the authors propose as a new therapeutic strategy, to be validated in clinical trials, neoadjuvant treatment with ICIs in patients with localized colon cancer.  

These new therapeutic strategies would have to be validated in the corresponding clinical trials. These trials would have to provide answers to several unknowns: optimal treatment duration, treatment window, benefit in terms of the pathological response of the primary tumor, recurrence rates, survival... If effective, they would have a major therapeutic implication, since they would modify the current standard of treatment, based on surgery for resection of the primary tumor and subsequent adjuvant chemotherapy in patients at risk.  

This is, therefore, a basic biology work that identifies this HRC population of residual cells, a population that is also found in the tumors of patients, as the authors demonstrate, and which opens the door to testing new therapeutic strategies to improve the treatment of colorectal cancer patients. The major limitation is that we now have to take the step to the clinic by performing the corresponding clinical trials that will allow us to validate this approach.