Emerging multimodal nanomedicines for breast cancer based on two novel drug encapsulation concepts: Mesoporous Organosilica Drugs and Drug Structure-Directing Agents

Abstract

Cancer causes millions of deaths worldwide each year. Last decades, great progress has been made in early cancer detection and therapeutic procedures, resulting in a mortality decrease. However, when the disease is in advanced stages and metastasis occurs, mortality is much higher. Moreover, cancer incidence increases every year and current therapies have serious limitations due to the appearance of drug resistance that limit the therapeutic efficacy, and to the associated serious adverse effects, which severely impair patients’ quality of life. Thus, improving current cancer treatments and developing new, more effective therapeutic strategies that minimise adverse effects is a priority for the scientific community. The research carried out in this thesis is directed towards this line, and specifically, it is framed within the field of nanomedicine. As for current cancer therapies, the removal of the tumour by surgery and radiotherapy are the usual treatments in the case of solid and localised tumours. However, when the cancer has spread to other parts of the body leading to metastasis, systemic treatment is necessary. Chemotherapy, the treatment of choice in these cases, presents toxicity problems leading to serious adverse effects that limit the dose that can be administered and, therefore, its therapeutic efficacy. Moreover, this severely compromises patients' quality of life. Another serious problem associated with chemotherapy is the emergence of drug resistance by cancer cells. Nanomedicine consists of the use of nanoparticles (NPs) of different types that act as nanovehicles that transport drug molecules to the organ or tissue where they perform their therapeutic action. Therefore, nanomedicine presents great potential as therapy for cancer treatment: the encapsulation of chemotherapeutic agents in NPs and their selective delivery to cancer cells can increase their therapeutic efficacy while avoiding adverse effects...