Description Module
The Description Module contains narrative descriptions of the clinical trial, including a brief summary and detailed description. These descriptions provide important information about the study's purpose, methodology, and key details in language accessible to both researchers and the general public.
Description Module path is as follows:
Study -> Protocol Section -> Description Module
Description Module
Ignite Creation Date:
2025-12-25 @ 1:34 AM
Ignite Modification Date:
2025-12-25 @ 1:34 AM
NCT ID:
NCT06452394
Brief Summary:
Despite modern surgical and medical treatments, breast cancer can re-occur and lead 20% of patients to death. During the last 20 years, pre-clinical studies have shown that treatment failures may be due to the presence of a sub-type of cancer cells, the cancer stem cells, which are resistant to chemotherapy and radiotherapy. By chance, doxycycline, an old, inexpensive and safe molecule seems to target effectively these cancer stem cells. This study proposes to check for the clinical efficacy of doxycycline to target the cancer stem cells and improve the response to neoadjuvant chemotherapy in ER+/HER2- breast cancers.
Detailed Description:
Patients with early stage ER+/HER2- breast cancer (BC) have a low pathologic complete response (pCR) rate of less than 15%. Over the past 20 years, studies have identified a subset of cancer cells with tumorigenic and stem-like properties, known as cancer stem cells (CSCs), that are involved in tumour initiation, metastasis, relapse and resistance to treatment. Cancer cells with stem-like properties are known to possess cellular plasticity that not only enables self-renewal capacity, but also exhibits high tumourigenic potential and resistance to oncological therapies such as chemotherapy and/or radiotherapy.
CSCs can arise from normal adult breast stem cells through mutations or directly from differentiated tumor cells. Tumour hypoxia has been shown to be one of the major factors promoting and maintaining the stemness phenotype. The metabolism of CSCs in hypoxia relies on a delicate balance between reduced energy requirements through reduced proliferation and an altered balance between mitochondrial oxidative phosphorylation ("OXPHOS") and cytosolic glycolysis, while maintaining mitochondrial redox homeostasis to control reactive oxygen species (ROS) levels. Any slight imbalance in mitochondrial redox homeostasis in CSCs, leading to transient effects on ROS, may promote their differentiation towards their non-stem tumour cell counterparts. Consequently, specific drugs targeting mitochondrial metabolism, leading to increased ROS levels, may destabilise CSCs.
This study proposes to check for the clinical efficacy of doxycycline to target the cancer stem cells and improve the response to neoadjuvant chemotherapy in ER+/HER2- breast cancers. The change in the stemness marker, ALDH1, assessed before and after treatment and the effect of doxycycline on the pathological response will be studied.
The translational work will be to better define these stem cells and to grow organoid cultures to study the effects of the different drugs in vitro. This study also aims to address a number of translational research questions using a tumor sample obtained from an additional core biopsy prior to treatment initiation and using a fresh tumor sample from the surgical specimen in the case of residual tumor after neoadjuvant treatment:
* Quantify and characterise the effects of doxycycline on tumors
* Identify factors that facilitate or prevent the effects of doxycycline
* Estimate the effect of doxycycline compared to other CSC-targeting drugs
Study:
NCT06452394
Study Brief:
Protocol Section:
NCT06452394