The Mesenchymal Stem Cell biomarker study

Chemotherapy remains the backbone of treatment for the majority of patients
with disseminated cancers. However, response to chemotherapy is often
transient. It is becoming evident that the tumor microenvironment plays a
crucial role in the development of resistance. For example, tumors can modulate
their microenvironment by recruiting different types of cells and making use of
the functions of these cells. One of these cell types are the Mesenchymal Stem
Cells (MSCs). Previous research has brought to light that these MSCs can
produce 2 types of fatty acids (PIFAs), that can induce chemotherapy
resistance.

The release of endogenous PIFAs may thus contribute significantly to the
development of chemoresistance. To our knowledge, it is currently unknown if
this accounts for different tumor types equally. The aim of this study is
therefore to determine the correlation between primary tumor type and baseline
MSCs level. A better understanding of this correlation could help to develop
specific interventions to improve the therapeutic index of chemotherapy.

Analyse the correlation between baseline MSC level in peripheral blood from
cancer patients and their primary tumor type.

This study aims at retrieving 16 ml of peripheral blood from patients suffering
from either CRC, gastric cancer, prostate cancer or sarcoma. The blood
withdrawal will always be combined with a withdrawal performed in the course of
regular diagnostics, or if venous access allowing blood withdrawal is already
in place. Patients will not undergo extra venepuncture because of this study.

A single blood withdrawal either combined with a standard of care venepuncture,
either performed using an existing intrvenous access point only poses a minor
burden on patients.