2. Chemotherapy and Immunotherapy
● Chemotherapy and immunotherapy work to kill
cancerous tumors in different ways
● Chemotherapy and Immunotherapy do not
have accurate delivery systems
● Nanotechnology delivery systems can lead to
much improved drug delivery accuracy
● Goal: apoptotic or necrotic tumor cell death
http://www.frontiersin.org/files/Articles/104683/fonc-04-00188-
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3. Immunotherapy & The Immune Response
● Refers to treatment of tumors by inducing
an immune response to attack and
destroy tumor cells
● T Cells are vital to the process of
removing cancerous tumors
● T Cell response are triggered when tumor
cells release antigens
● Research suggests that when
chemotherapy and immunotherapy are
used together they may have synergetic
doi:10.1038/nrc1613
4. Drug Delivery - A Brief Introduction
Designing new drugs requires years of research and testing, very expensive
Instead, if we improve how efficiently our drugs work, we can make huge strides
in medicine by using things we’ve already invented
Drug delivery involves attaching the active ingredient to some kind of device or
molecule which will bring it to the area of interest
In the case of Nanotech Drug Delivery, this involves using a nanoparticle carrier
5. Nanoparticles.
● 1-100 nm in width
● Can have varied
properties
○ Physical
○ Biological
○ Chemical
● Often either a metal or
lipid
8. Drug Targeting
The main challenge this technology faces is improving the method of delivery.
An appropriate compound must be selected to which our nanoparticle will bind
to ensure it is absorbed into the cancerous cell via endocytosis.
Proposed Targeting Methods
Low density Lipoprotein (Cholesterol): Lipoproteins are proteins that move lipids around the body and
facilitate them being taken up by cells. Cancerous cells uptake 100 times more LDL than normal
cells, so binding the nanoparticles to LDL is a proposed drug carrier
Folic Acid: This compound participates in nucleotide synthesis, so rapidly dividing cells like cancerous
ones need a lot of it. Folate receptors are highly overexpressed in cancer cells, so binding the
nanoparticle to it is potentially a very good way to get the drug inside the cell.
Many many more...
9. Drug Release
- Can be regulated by a variety of factors via selective solubility:
- pH sensitive
- Electromagnetic Waves
- Glucose and and salt concentration
- With better drug delivery systems, treatment can be much more efficient
- Less undesirable side effects with more accurate drug testing
http://cen.acs.org/content/cen/articles/91/web/2013/02/Multiblock-Polymer-Nanoparticles-Attack-Tumors/_jcr_content/articlebody/subpar/articlemedia_0.img.jpg/1466565923108.jpg
11. Engineering Challenges
Limited research in the field
Professional collaboration
Precision of nanoparticles
As the technology improves so will
effectiveness of drug delivery
Drug mediation
12. Challenges
Adapting pre-existing methods
Expansion of old technology into new fields
Targeted delivery
Developing methods for the nanoparticles
to seek out tumors
Cornell dots could provide a solution
to several issues
Nanoparticles.
The Food and Drug Administration (FDA) defines a nanoparticle as any material with a dimensional range of approximately 1 to 100 nm or end products with a dimension up to 1 [micro]m that exhibit properties or biological phenomena (chemical, physical, and biological effects). Nanotechnology-based drug delivery systems have gained scientific notoriety due to variety of applications and many benefits; these systems may include polymeric and lipid-based nanoparticles.
Hydrogels
A hydrogel is a network of polymer chains that are hydrophilic and promote the drug release through the spaces formed in the network via dissolution or disintegration of the polymeric matrix. Hydrogels are classified as stimuli-sensitive swelling-controlled release systems because they can respond to various environmental conditions, such as pH, the surrounding fluid ionic strength, temperature, an applied electrical or magnetic field, or glucose level changes. These changes promote altered network structure, swelling, mechanical strength and permeability. Thus, hydrogels maybe used to improve drug delivery
Liposomes
Liposomes have attracted the attention of the scientific community due to their high versatility. Liposomes have greater therapeutic efficacy than conventional pharmaceutical system because they promote slow drug release at the target site. Furthermore, liposomes are less toxic, nonimmunogenic, and biocompatible with organic tissues. They can decrease systemic toxicity and improve drug efficacy, especially for antibiotics, antifungals, and anticancer drugs. Thus, using liposomes as a delivery system for chemotherapeutic agents.
The design of nanoparticles is crucial to their efficacy in fighting against cancer cells. Often times, the nanoparticles themselves are made up of a metal, such as gold or silver. These metals have been shown to have very little bacterial development within varying levels of pH within the body and minimal (if any) reactivity to the chemistry of the drug itself. However, other metals such as copper have been used in some experimental studies which do show some success but there are a few risks involved. The metal itself has concentrations of different cancer fighting drugs which diffuse across the cell membrane in order to fight the cells. The diffusion also occurs in circulatory cells which would result in the circulatory environment having the exposure to the drug. Therefore, additional cells in the environment that may be momentarily benign cancer cells would react to the drug. These processes can be done either by individual nanoparticles, or with a nano-scale system referred to as a nanodiamond.
The nanodiamond also serves as a drug delivery platform that specifically binds to cells, however different polyethlenimine polymers must be introduced in order for circulation to occur. The complex itself is positive due to amine groups of the polymer backbones for gene-specific treatment. The nanodiamond itself binds to different ligand sites in order for the treatment to occur, thus posing a more difficult task than diffusion via individual nanoparticles.
Imaging techniques have also been important in developing nanotechnology methods. Different nanoprobes have been used in order to label and mark different tumor cells in order to specifically target later on for drug-delivery mechanisms. The use of magnetic nanomaterials as imagining agents have helped for this since the process is done via MRI technology. Another technology method is the combination of fluorescent imaging with MRI. This is due to tracing of the manganese oxide and other folate-conjugated substances on the coating of nanoparticles which becomes indicated by both pieces of equipment. This results in a more accurate determination of location and display cancer cells locations/displacement in solid tumors.
Hydrogel technology works in a similar to nanoparticles, however the gel itself acts similar to the metal nanoparticle carrier. The gel acts to reduce the amount of anti-inflammatory agents around the surrounding tumor area. The inflammation results in immune system cells to the targeting area in order to combat the tumor with the use of the drug in it.
Cornell Dots-infused with organic dye which will light up with fluorescence. diagnostic tool to assist surgeons to identify the location of tumor cells
