Can you guess the versatile instrument Dr. Andre Geim and Dr. Konstantin Novoselov used to earn the Nobel Prize in 2010? You’re right if you guessed tape! (“The Nobel Prize in Physics 2010”, ). While adhesive tape, commonly used to wrap one’s Christmas presents, may seem ordinary to most in the scientific community, the discovery of graphene was nothing short of revolutionary. The two scientists were able to isolate one single layer of graphene from the graphite of a pencil; using tape, the researchers were able to stick one single layer of this incredible substance to the adhesive. The incorporation of graphene into research related to renewable energy, electronic circuits, and medicine has truly broadened the horizons of science across several fields.
|Figure 2. Structure of Graphene and Other Carbon Allotropes (Bella, Cauda, de Bortoli and Gnazzo 17)|
The first attempts to use graphene as a drug delivery mechanism were conducted by the Hongjie Dai group at Stanford University in 2008 which found an effective way to load anticancer drugs onto a graphene surface for intracellular drug delivery (Feng and Liu). Now, in early 2015, with more and more advances in research surrounding graphene, University of Manchester scientists have found that graphene oxide (GO) a form of graphene can be used itself to combat cancer metastasis (Fiorillo et al. 3554). Metastasis, the spread of cancerous tissues to other parts of the body accounts for 90% of cancer deaths. Thus, combatting cancer stem cells (CSCs) that give can give rise to tumor cells is incredibly important. Traditional cancer therapies such as chemotherapy and radiation only rid the body of ‘bulk’ cancer cells or non-stem cell cancer cells which makes this discovery all the more important (Brown). The team led by Professor Lisanti and Dr. Vijayaraghavan found that GO inhibits tumor-sphere formation across many cancer lines including breast, ovarian, prostate, lung and pancreatic cancers, as well as glioblastoma (Fiorillo et al. 3555) . Additionally, the group found that GO is non-toxic to fibroblasts implying that the use of GO would only target CSCs and not benign tissue (Fiorillo et al. 3557). Investigating the mechanisms behind GO’s success against CSCs, the team found that GO inhibits several key signal transduction pathways that promote cancer cell proliferation (Fiorillo et al. 3559).
The benefits of a targeted approach to cancer cell death are undeniable. Specifically, the use of GO, which is toxic to CSCs but not to non-cancerous tissue, provides a unique method of preventing metastasis without harming patient’s bodies as a whole. Applications of this study involve nanotherapy of GO given to the patient through intravenous liquids or through lavage in surgery (Brown). Since graphene is stable when mixed in water, therapies that deliver GO in an aqueous solution are possible. In particular, using GO as a lavage is beneficial in that the rinse would rid the body of CSCs preventing further tumor development after the surgical retraction of tumors (Brown).
Ultimately, the unique properties of graphene and GO are incredibly important in the future of cancer research. GO’s ability to enter cell membranes and target certain cell types make it an ideal drug. Currently, conventional cancer treatments only eliminate bulk cancer cells but fail to solve the root problem that stems from CSCs. The fact that GO can be used to prevent recurrence of cancer offers hope to many cancer survivors. While recurrence statistics regarding all cancer patients aren’t available, recurrence in different forms of bladder cancer can range from 50-90% proving it is imperative to treat remaining cancer stem cells in the body (“Cancer Treatment & Survivorship Facts & Figures” 18).
However, graphene’s unique properties also could cause GO to be hazardous not only to patients but also to researchers. For researchers using GO as well as technology users (essentially everyone in the modern era), inhalation of nanoscopic platelets of graphene has the potential to act in the body like other materials such as asbestos and silicon dust whose implications involve respiratory irritation as well as cancers such as malignant mesothelioma. The main problem of graphene as described by University of Edinburgh toxologist is that its particles are unable to be filtered by the body and are too big to be engulfed by white blood cells (Bradley 230). While such accounts of graphene toxicity are certainly concerning, graphene’s negative effects to date have only been seen if the graphene were aerosolized; the likelihood of the negative consequences is further reduced since if inhaled, graphene will most of the time be inhaled within liquid droplets according to Andrew Maynard, Director of the Risk Science Center at the University of Michigan (Bradley 230). Furthermore, when graphene is incorporated into a polymer for instance, the graphene would not be released into the air, consistent with most uses of graphene (Maynard). Thus, though certain uses of graphene could be toxic, most scenarios describe favorable effects of graphene. Instead of stopping research concerning graphene and its many forms, researchers ought to continue researching both the new applications of graphene whilst also examining potential side effects. Ultimately, a question we may ask ourselves is “have I ever scribbled with a pencil on a piece of paper?” Because if the answer is yes, you have dealt with one of the most interesting materials in research today, even in your day-to-day lives. Let us not forget that scientists Andre Geim and Konstantin Novoselov discovered graphene through this very act of scribbling using graphite pencil and picking up graphene with a humble piece of tape.