Application of Nanotechnology in Cancer Treatment

What is a nanoparticle?

A nanoparticle is a small structure of variable shape and size in nanometer range made out of tiny molecules or atoms. Due to their interesting properties, nanoparticles are widely synthesized in different shapes and sizes and applied in various fields including drug delivery in cancer treatment.

Nanocomposites of suitable shape and size can be designed to carry a drug inside of it and that allows us to send that package to different places where we want that drug to go.

Nanotechnology, the science of building small is changing the way we look at cancer more importantly the way we look at diagnosis and treatment. Nanotechnology allows researchers to build new tools that are actually smaller than cells giving them the opportunity to attack cancer at the cellular and genetic level.

Nanotechnology not only enables health practitioners to detect cancer earlier but also holds the promise of stopping cancer before it even develops. This revolutionary approach is so precise that doctors will be able to design a unique treatment for an individual's own medical and genetic profile. Multiple lab tests can be done more rapidly and at a much lower cost using one nano device.

According to American Cancer Society, lung cancer is the most common cancer in male and breast cancer is the second most common cancer in the female.

Background of cancer treatments

The various current treatments for cancer include

Surgery

Surgery aims to physically cut out the tumor. In general it is used as a curative treatment but can also be used in certain circumstances as a palliative treatment in order to improve quality of life.

Radiation therapy

Radiation therapy uses targeted radiation to kill cancer cells. It involves the use of high energy rays like x-rays or electrons to kill cancer cells. It can be given externally by a machine to direct rays at cancerous tissue or internally by placing radioactive material in the body near cancerous cells.

Medical therapy

Medical therapy is a broad category that involves medications given to kill cancer cells. Most commonly this is in the form of what we call cytotoxic chemotherapy which simply put our drugs that kill fast dividing cells. Medical therapies however also include other medical treatments that don't necessarily involve cytotoxic drugs; examples include hormone therapies, antibody therapies and immunotherapies which are aimed at helping the immune system fight off the cancer.

Targeted therapy

Targeted therapies use small molecules that are designed to target and inhibit mutated proteins that are found in specific cancer cells.

How is nano technology improving the cancer treatment?

In case of traditional treatment all cancer cells as well as the healthy cells are killed as both the cells get the drugs. In chemotherapy, the anti-cancer drugs damage both the cancer cell as well as the normal cells therefore, we need a direct delivery strategy that can selectively kill only the cancer cells and protect the healthy cells.

In case of nanotechnology, nanoparticles specifically go and bind only to the cancer cells and it kills only the cancer cells. The healthy cells are unaffected so it is highly specific and targeted and it is protecting the healthy cells and it is killing only the cancer cells.

Nanotechnology may help in increasing their solubility and bioavailability of the drugs that means the most of the anti-cancer drugs are hydrophobic in nature so by using this nano carrier we can encapsulate this hydrophobic anticancer agent attracted to the nano carrier and it will also increase the bioavailability of the drugs due increase in the atom efficiency.

When compared to the traditional methods, we can attach more than one drug in the same nano carrier for delivery of multiple decks at the tumor site. Non drug therapies for example photo thermal or photo dynamic therapy is also possible by using nano materials.

The objective of targeted cancer therapy is to deliver chemotherapeutics directly to the cancer tissues while minimizing undesirable toxicity to the rest of the body.

Block co-polymer based polymeric nanoparticles are widely used as a platform for co-delivery of drugs associated with multiple functions. A block copolymer is a copolymer formed when the two monomers cluster join together and form 'blocks' of repeating units. A dye block copolymer is composed of two joined polymer chains – a hydrophilic or water-loving block shown and a hydrophobic or water fearing block. The hydrophobic blocks are surrounded and stabilized by the hydrophilic blocks. This polymeric coating can be subsequently modified with various counsel targeting ligands such as antibodies or small molecules. 

The nanocomposite to be used for cancer treatment can be modified into a form to allow for intravenous administration. The nanoparticles are quickly distributed throughout the body by the circulatory system with which they are also delivered to the site of the tumor one hundred times smaller than red blood cells. Nanoparticles possess the unique ability to permeate through the leaky walls of tumor vasculature. Through this passive targeting technique the nanoparticles can be concentrated within the tumor tissue on the cancer cell surface membrane.

The nanoparticles encounter the surface receptor molecules and microscopic markers expressed on cancer cells but not expressed by normal tissue, where the nanoparticles targeting ligands bind specifically to these receptors triggering a response also known as receptor mediated endocytosis which draws the nanoparticles into the cancer cell this process enables thousands of nanoparticles to enter into each of the targeted cancer cells.

Conclusion

So we're able to engineer nanotechnology for cancer application that can identify the differences between a normal cell and a cancer cell and specifically kill the cancer cell while leaving a healthy cell alone. These nanoparticles travel the same pathways in the body that a tumor cell takes the nanoparticles.