The use of nanotechnology in the treatment of cancer offers some exciting possibilities, including the possibility of destroying cancer tumors with minimal damage to healthy tissues and organs, as well as the detection and removal of cancer cells before they form tumors.
Most efforts to improve cancer treatment through nanotechnology are in the research or development stage. However the effort to make these treatments a reality is highly focused. For example, the Alliance for Cancer Nanotechnology, created by the US National Cancer Institute, is promoting innovation and collaboration among researchers to address some of the major challenges in the application of nanotechnology to cancer. In addition, there are many universities and companies around the world that work in this area. It is possible that these efforts will result in cancer being almost eliminated in a decade or so, just as vaccines almost eliminated smallpox in the last century.
The following section provides examples of ongoing research, some of the methods discussed have reached the preclinical or clinical trial stage.
Cancer therapies are currently limited to surgery, radiation, and chemotherapy. All three methods run the risk of damaging normal tissues or incomplete eradication of cancer. Nanotechnology offers the means to direct the therapies directly and selectively to the cancer cells.
Nano-carriers
Conventional chemotherapy employs drugs known to kill cancer cells effectively. But these cytotoxic drugs kill healthy cells in addition to tumor cells, leading to adverse side effects such as nausea, neuropathy, hair loss, fatigue and impaired immune function. Nanoparticles can be used as drug carriers for chemotherapy to deliver medication directly to the tumor while saving healthy tissue. Nanocarriers have several advantages over conventional chemotherapy. They can:
• Protect medications against body degradation before reaching your goal.
• Improve drug absorption in tumors and cancer cells themselves.
• allow better control over the timing and distribution of drugs in the tissue, facilitating oncologists the evaluation of their functioning.
• prevent drugs from interacting with normal cells, thus avoiding side effects.
Passive segmentation
There are now several nano-carrier based drugs on the market, which depend on passive targeting through a process known as "better permeability and retention". Due to their size and surface properties, certain nanoparticles can escape through the walls of the blood vessels into the tissues. In addition, tumors tend to have leaky blood vessels and defective lymphatic drainage, causing the nanoparticles to accumulate in them, thereby concentrating the cytotoxic drug attached where necessary, protecting healthy tissue and greatly reducing adverse side effects.
Active Orientation
On the horizon are nanoparticles that will actively target drugs to cancer cells, based on the molecules they express on their cell surface. Molecules that bind particular cell receptors can bind to a nanoparticle to actively target the cells expressing the receptor. Active targeting can even be used to introduce drugs into the cancer cell, inducing the cell to absorb the nanocarrier. Active targeting can be combined with passive targeting to further reduce the interaction of drugs transported with healthy tissue. Activated and passive targeting activated by nanotechnology may also increase the efficacy of a chemotherapeutic, achieving a greater tumor reduction with lower doses of the drug.
Destruction from within
By moving away from conventional chemotherapeutic agents that activate normal molecular mechanisms to induce cell death, researchers are exploring ways to physically destroy cancer cells from the inside. One of these technologies - nanhellas - is used in the laboratory to thermally destroy tumors from the inside. Nanoshells can be designed to absorb light from different frequencies, generating heat (hyperthermia). Once cancer cells take nanoscales (through active targeting), scientists apply the near-infrared light that is absorbed by nanocapsules, creating intense heat within the tumor that selectively kills tumor cells without disturbing healthy cells Neighbors.