Research Scientist and Research Specialist at Nabio Consulting, Marian Jiya John, talks about the benefits of treating breast cancer with Nanomedicine.
Breast cancer is the most prevalent cancer among South African Women. According to the National Cancer Registry (2014), 1 in 27 women in South Africa are at a risk of developing breast cancer in their lifetime. Early detection is the key to an effective treatment and a positive prognosis.
Breast cancer / tumour are mostly stimulated by overexpression of the hormone receptors such as estrogen, progesterone and human epidermal growth factor-2 receptor. The most aggressive form of breast cancer is the triple negative breast cancer (TNBC), as it lacks a hormone receptor for targeted hormone therapy. TNBC has poor prognosis, low survival and high relapse rates.
New innovative breast cancer treatment
Generally, breast cancer treatment includes surgery, chemotherapy and radiotherapy. However, the major drawbacks of the drugs used in chemotherapy are non-specific targeting and suboptimal bioavailability of the drug in the tumour tissues. Nanomedicine has emerged as a promising alternative option to overcome these limitations, with fewer side effects and improve the quality of life for survivors.
Nanomedicine is a modern interdisciplinary science that applies nanotechnology to the field of medicine. Nanotechnology deals with the engineering of materials at a nanoscale level, which is usually between 1 – 100 nm. The following are examples of nanoparticles that are used as carriers of anti-cancer drugs; liposomes, micelles, gold nanoparticles, and many more. Due to particles size, nanoparticles can easily penetrate into the cell membranes and bypass many biological barriers such as Blood Brain Barrier (BBB) particularly for brain cancer.
Benefits of Nanomedicine in treating breast cancer
Advantages of using nanotechnology in combating cancer include early detection, rapid diagnosis and targeted drug delivery. Nanoparticles can be surface functionalised with different ligands such as proteins, monoclonal antibodies, folic acid, carbohydrates, fructose, receptors and many more. Functionalised nanoparticles with ligand facilitate target delivery of anticancer drugs to specific tissues or site of action, with minimum damage to healthy cells. In TNBC, gold nanoparticles conjugated with folic acid were able to enter the breast cancer cells membrane easily, which indicated that the presence of folic acid as ligand facilitated the uptake of nanoparticles by folate receptors. Another example, fructose-coated nanoparticles have shown high selectivity to breast cancer cells compared to normal cells.
A common characteristic of solid tumours like breast cancer is that it has leaky blood vessels. In this case, nanoparticles are able to enter through the leaky blood vessels due to its small size, accumulate and retain within the tissue, employing passive drug targeting called the enhanced permeability and retention (EPR) effect. EPR can increase the bioavailability and drug delivery specificity in breast cancer cells. Nanoparticles can also be used as contrast agents in MRI scanning for treatment monitoring purposes.
The following are some the examples of nanodrugs Food and Drug Administration (FDA)-approved for breast cancer treatment:
- Doxil is the first FDA approved nanodrug (1995). Doxil contains Doxorubicin in polyethylene glycol (PEG) – coated liposomes, which reduced the cardiotoxicity substantially, without compromising the anticancer effect of the drug.
- Abraxane (2005) is an albumin coated paclitaxel, which resolved the solubility issues and enhanced rapid, preferential delivery and accumulation of paclitaxel at the tumour site.
- Lipoplatin, a liposomal nanoparticle that carries cisplatin, is another nanodrug that has successfully completed phase I – III clinical trials. Lipoplatin has shown to substantially reduce the side effects of cisplatin such as renal toxicity, peripheral neuropathy, ototoxicity and myelotoxicity while retaining the efficacy of the drug.