Why Some Cancers are Hard to Treat

In mass media, we are frequently informed about treatments to diseases like leukemia, lymphoma, and Crohn’s. But rarely do we hear: “We found a cure to cancer!” So, one may wonder: what makes curing cancer such a seemingly impossible task, and what distinguishes it from other diseases?

There is one fundamental reason why cancers are difficult to eradicate: these cells adapt and evolve in response to treatment (Fodale, Pierobon, Liotta & Petricoin, 2011). Thus, even if a treatment is initially effective, its impact starts to dwindle, since the biological components that it blocks eventually “re-wire” themselves to circumvent the treatment (2011).

Chemotherapy – a method of using drugs to attack malignant (harmful) cells – is performed on 67% of all cancer patients (“Chemotherapy,” 2014). Yet, these

Figure 1. According to the diagram, tumor blood vessels have a squiggly or nonlinear path, unlike normal blood vessels, which is evidence of their highly abnormal tumor vasculature. In addition, the lack of the orange patches at the edge of the vessel represents the lack of supporting cells, caused by its hyperpermeable structure (Wilson & Brown, 2004).

drugs can be resisted by cancer cells (“House call: What is metastasis?,” 2016). For example, studies conducted by a group of scientists at the MD Anderson Cancer Center, which participates in therapeutic clinical research exploring novel treatments for cancer, show that cancer cells can travel to different parts of the human body, known as metastasis (2016). This makes it especially difficult to track down cancer cells and prevent them from spreading (2016). However, scientists have found that cancer cells use a protein called PGC-1a, which helps form new mitochondria, used to harness energy (Tan etal., 2016). Using this energy, they metastasize to different parts of the body and find a new home to live in, making it hard for scientists to track them down (2016).

Tumor cell expansion is further proliferated by its uncontrolled growth (Eales, Hollinshead & Tennant, 2016). Scientists have found that the deformed tumor blood vessels cause regions of hypoxia or oxygen-deprived conditions (2016). Hypoxia – a condition in which the body is deprived of adequate oxygen supply – arises in tumors through the rapid proliferation of cancer cells, which causes the tumor to exhaust the nutrient and oxygen supply from the normal blood vessels (2016). However, the tumor-proliferating effects of hypoxia cannot be generalized because they can either have detrimental or beneficial effects depending on severity, duration, and context (2016).   

Yet there are even more ways that cancer cells can adapt: they manipulate an enzyme called PKM2 (Prescott, 2011). By keeping PKM2 levels low, the cancer cells channel incoming glucose to metabolic pathways that generate antioxidants, thereby surviving oxidative stress, the imbalance between the production of free radicals and the ability of the body to counteract their harmful effects (2011). Thus, it is hard for scientists to investigate PKM2 manipulation by cancer cells (2011).

Despite the adaptive nature of cancer, oncologists are continually learning more about cancer cells (Evan, 2014). For example, professor Gerard Evan, head of the Department of Biochemistry at the University of Cambridge, is studying the genes that drive the development and growth of cancer, called oncogenes (2014). To combat the disease, Evan uses genetically engineered mice, which enable him to toggle on and off tumor suppressor genes (2014). This allowed scientists to identify the most effective therapeutic targets and employ a range of molecular biology technologies to address roles played by key oncogene signaling pathways in the genesis and progression of cancers (2014). These technological advancements help develop effective treatments to combat the adaptive nature of cancer in the future.

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Expand your Scientific Research Skills at Tech!

If you’re the type of student who is interested in learning and writing about the breakthroughs in the world of science and technology, the Science Engineering Research Program (SERP) is right for you! This STEM-centered program aims to make the students of Staten Island Tech better researchers and writers with high-level essay skills.

Students from the program in 2017.

All underclassmen are encouraged to consider taking part in this program because while there isn’t an entrance exam for this rigorous program, dedication is required. Upperclassman can still join if they show that they are interested in research by taking initiative and starting their own research projects.

Throughout the years, SERP will assign you a set of research papers, or “tasks”, to complete with time constraints, which will be strictly graded on how accurately and coherently you present your research finds. Thus, this program will be fit into your schedule as an actual class and counted towards your GPA. However, if you find yourself under too much pressure or cannot cope with the heavy workload, you are allowed to opt out and continue on with your original schedule.

So, why would you join this program in the first place? Are all those long hours of studying and tedious research worth it?

The answer is, yes!

There are many skills that are heavily enforced by SERP that will aid you in the transition into college. Most professors lecture for a majority of class time, but will not fail to assign research papers to complete. The professors do this in order to make you think more critically about the information you’re given and not just fall for invalid claims. Thus, SERP is a great way to build this mindset and to prepare for the workload you’ll face in college. In addition, the fact that you participated in SERP for all four years in your high school career showcases your motivation and willingness to take on challenging courses. You get to do research papers on any topic of your choice, anywhere between biology, medicine, astronomy, engineering, and more.

Despite the hard work and tedious research required for this program, SERP can also be a very enjoyable experience because of the connections you have access to. If you’re having trouble with any of your research, upperclassmen can guide you through the process and help you out. For example, if you join SERP in your freshmen year, the juniors and seniors who have had previous experience with SERP will teach you specifics on how to write a research paper and how to sift through credible sources. The SERP community is just one factor that is desirable about the program. In addition to being a very enjoyable learning experience where are you are able hone necessary professional skills exponentially, SERP is a place to be surrounded by motivated, like-minded, and STEM-oriented leaders of the future.