Cancer is defined as an abnormal and pathological condition that affects a part or all of an individual. The disease is most caused by abnormalities in cell division and its cycle at various stages. The abnormal proliferation of the cells leads to cancer and is the one of the major cause that kills the patients across the world (COLIN, DM et al., 2001). Various approaches of the treatment are available for the treatment of disease that include conventional mode (MALCOLM, RA , 2001) and alternative (novel) approaches of drug delivery (RAYMOND & GERT, 2008). The conventional mode includes administration of anticancer drugs in the form of injections (chemotherapy), surgery, radio therapy or combination of both. The treatment is associated with adverse events that include hair loss, unwanted exposure to healthy cells, anaemia and proneness to infections. The side effects limit the treatment and reduce the patient compliance. Hence novel approaches (alternative) would be used in the treatment of cancer.
The present paper describes the alternative approaches for the treatment of cancer to enhance the health and decrease the incidence of cancer.
Drug loaded liposomes: Anticancer drug (Doxorubicin, Doxil®) used in the treatment of Kaposi’s sarcoma, ovarian cancer and multiple myeloma (LUDWIG et al., 2007). The drug loaded vesicular system after injection into blood; they enter the tumour site through leaky vasculature and release the drug in the neoplastic tissue.
Immunotherapy: The anticancer drug is loaded in a liposome or nanoparticles and they further tagged with an antibody. The antibody recognises the tumour site and binds with antigens. Eventually the drug is released and penetrated into the tumour. The nanocarriers may be coated with polyethylene glycol to circulate the delivery system quite long time.
Targeted therapeutics (Monoclonal antibodies, Mab): The Mabs obtained from single strain of antibodies such as rituximab (Rituxan/MabThera) and trastuzu Mab (Herceptin) recognizes the antigens that are over expressed on the surface of tumour.
Vaccines: The vaccination with an autologous cell based vaccine, Sipuleucel-T. The vaccine stimulates the patient’s immune system to produce T-cells against antigens. The vaccine serves as a first line treatment in the prostate cancer and is administered by intravenous infusion at weeks 0, 2 and 4 (LAWRENCE & BRUCE, 2012).
Gene-directed enzyme prodrug therapy (GDEPT) The tumor cells are transfected with a gene for an enzyme that is produced at the cancer site and activates a systemically delivered prodrug. Then the active drug is liberated and elicits its pharmacological action
Antibody-directed enzyme prodrug therapy (ADEPT): The anticancer prodrug, an enzyme and a Mab are linked together. The Mab directs the antigenic substances that are over expressed on tumour site and supports in binding. The enzyme converts the prodrug to active drug and it further shows the anticancer activity (NALAN, 2011).
- Doxil liposomes are effective against wide variety of cancers. Since the leaky vasculature present only in tumour, the drug release takes place in tumour rather than healthy cells.
- Mabs are effective and better cytotoxics compared to anticancer agents. They selectively and specifically bind with the tumour antigens and elicit the anticancer property. Hence the health cells are not affected and the individual would be benefitted from its selective action
- Vaccines stimulate the body to produce the T-Cells and they act against the antigenic substances. Hence no side effect would be anticipate to the healthy cells as the antigens are only present on cancerous tissue
- GDEPT and ADEPT are the promising technologies to deliver the drug selectively to the target tumour site. Hence adverse events can be minimized.
- Doxil formulation show toxicities such as hand and foot syndrome and the patient develops doxorubicin resistance
- Nanocarriers may release the drug in unwanted site i.e., healthy tissue due to the structural lysis.
- Mab are expensive and increases the cost of therapy.
- Vaccines are available for prostate cancer and not available for other types of cancers
- The technologies, GDEPT and ADEPT are at initial stages and have to be proved clinically for their efficacy and safety
The alternative approaches for targeting cancerous tissue were discussed along with the advantages and disadvantages. The approaches are associated with low incidence of adverse events compared to the conventional modes of treatment. The complimentary or alternative modes are desired to enhance the patient’s health.
COLIN, DM., CYNTHIA, B-P., ALAN, DL & CHRISTOPHER, JLM. (2001) Cancer incidence, mortality and survival by site for 14 regions of the world. World Health Organization page 1-47 Retrieved from https://www.who.int/healthinfo/paper13.pdf
LAWRENCE, D-C & BRUCE, T (2012) Prostate cancer overview. Part 2: metastatic prostate cancer British Journal of Nursing, 21(18) p S23-S28
LUDWIG, H., STRASSER-WEIPPL, K., SCHREDER, M & ZOJER, N (2007) Advances in the treatment of hematological malignancies: current treatment approaches in multiple myeloma. Ann. Oncol. 18, ix64-70.
MALCOLM, RA (2001) Cancer from Encyclopaedia of Life Sciences Retrieved from https://web.udl.es/usuaris/e4650869/docencia/segoncicle/genclin98/recursos_classe_(pdf)/revisionsPDF/Cancer.pdf
NALAN, U (2011) New approaches to treat cancer- what they can and cannot do Biotechnology Healthcare Winter, p. 25-27
RAYMOND, MS & GERT, S (2008) Liposomal nanomedicines as anticancer therapeutics: Beyond targeting tumor cells International Journal of Pharmaceutics 364, p 258-264