Docetaxel-loaded solid lipid nanoparticles as a basis for a targeted and dose-sparing personalized breast cancer treatment strategy.

Abstract

Dear editor The long-term survival rate of patients with breast cancer was improved by the application of systemic adjuvant chemotherapy,1 although the primary breast cancer treatment strategy consists of mastectomy with lymphadenectomy and radiotherapy followed by breast reconstruction.2–5 Unfortunately, most adjuvant chemotherapeutic agents trigger major side effects.1,6 Therefore, we have read with great interest an article in the International Journal of Nanomedicine on the design of docetaxel-loaded solid lipid nanoparticles (DSNs) aimed at reducing the systemic toxicity of standardized docetaxel treatment.7 Our congratulation to the authors7 for their clear demonstration of the reduced cytotoxicity of DSNs and significantly decreased myelosuppressive toxicity by recovering the proliferation and differentiation of bone marrow progenitor cells, while triggering more apoptosis in MCF-7 cells at a low dose compared with the commercial formula of docetaxel by an arrested cell cycle progression in the G2/M stage. The acute necessity for such state-of-the-art studies is linked to a high worldwide incidence of breast cancer; in the World Health Organization Fact sheet, its increased metastatic potency is listed as one of the most common causes of cancer death.8 The incidence of breast cancer is high in Western European countries, ie, about 89.7 per 100,000 women.8 The same high incidence applies to other developed countries. For our part, we have analyzed the statistical data concerning breast cancer in the Russian Federation.9 According to the statistical report by the Federal Research Institute for Health Organization and Informatics of the Ministry of Health of the Russian Federation between 2003 and 2012 (Table 1), the 10-year breast cancer incidence rates average 68.99 per 100,000 women (an average of 52,647 women annually), of which 95.1% cases were histologically verified. The average 5-year survival rate was 56.2% among women with breast cancer followed up in state and municipal cancer institutions. The average annual mortality of patients with verified breast cancer was 10.0% among individuals who were followed up in cancer institutes. Subsequently, between 2003 and 2012, about 25,697 women per year died of breast cancer in the Russian Federation. Table 1 Modified data from a statistical report for 2012 by the Federal Research Institute for Health Organization and Informatics of the Ministry of Health of the Russian Federation Our investigation, as proved by time series analysis (JMP7 software), revealed that the incidence of breast cancer had been rising continually, with increasing trends from 2003 to 2012 while at the same time the number of cancer deaths has been steadily decreasing (Table 1). Overall, the same trends exist for all cancer patients, in the same time. This phenomenon can be explained first by improvements in the Russian health care system. Government programs were set up applying new diagnostic technologies for early breast cancer screening, and preventive medical strategies were encouraged. Second, the rise in incidence of breast cancer might also be associated with gradual lifestyle changes. Many mothers in Russia decline breastfeeding and, in addition, worldwide environmental changes are reflected in an increased incidence of breast cancer, including in countries with a low prevalence of the disease. This brief analysis demonstrates that our modern community calls for new therapeutic approaches in the treatment of breast cancer. We believe that further studies could show the application of DSNs to be a basic compound for a targeted and dose-sparing personalized breast cancer treatment strategy.