Biological Importance:
Cancer Cells research has developed rapidly over the last century with people worldwide becoming more and more aware of the different forms of cancer, but the topic itself still includes unanswered questions about how cancer forms and the structure and function of them. Although scientific and medical research has advanced, people are still building an understanding on the topic. Hence, why cancer cell research is extremely important biologically, and advancements in the topic have made a significant difference in the world. The importance of understanding cancer cells as information grows and new developments are found in cures is becoming more evident. Thus, to continue to understand the vitality of the research, people in societies of the world must be educated on the preventatives of cancer cells and the research found so far. An example of this study could be what researchers at the Australian National University (ANU) discovered, that starving cancer cells of nutrients can reduce their growth by up to 96 percent (ABC News, 2016). Evidently, this shows the biological importance of cancer cells research and how the rapid development of information, new discoveries and breakthroughs in research over time allows for human growth and understanding of the imperative topic.
Comparative Insight into growth, function and structure:
Cancer is a disease of unrestrained growth and multiplying where cells have escaped the body’s normal growth control mechanisms and have gained the ability to divide indefinitely. It is a multi-step process that requires the build-up of many genetic changes over time (Cancer Council Australia, 2017). “In eukaryotes (fungi, plants, and animals), cells replicate by mitosis followed by cytokinesis (Evans, Ladiges and McKenzie, 2005).” Through cell division and replication, the process of mitosis occurs when genetic information within the nucleus is copied and passed on to what is known as the two ‘daughter’ cells. This process is what a normal somatic cell undergoes during systematic cell replication (Evans, Ladiges and McKenzie, 2005). By disrupting the processes controlling normal cell division, a cell experiences abnormalities and becomes more commonly known as a cancer cell (Figure 2a). Cancer cells have two evident features of which define this abnormality. Firstly, there is an abnormal number of chromosomes (aneuploidy) present when the process is disrupted and secondly, a large scale of rearrangements in the structure of chromosomes. These anomalies in chromosomes are caused by an instability in genomic cells essential to most cancers. Instabilities such as chromosomal instability (CIN) and chromosome structure instability (CSI) arise through the persistent loss or gain of whole chromosomes forcing consequences of improper repair of DNA damage in somatic cells replication (Thompson, Compton, 2017). Therefore, the abnormalities that occur are caused by structural instabilities and rearrangements of chromosomes and the effects of mutations that occur forming a tumour.
A cancer cell is created through normal cells developing irregular functions, often resulting from genetic abnormalities inherited or are influenced by environmental factors such as UV light, X-rays, chemicals, tobacco products or viruses (Learner.org, 2007). These environmental factors are known as carcinogens as they are not inherited. Carcinogens are substances and exposures that may lead to cancer, however, some lead to cancer in other ways as they do not affect DNA directly. This being said they do not always cause cancer, some substances have different ‘levels’ of causing cancer (Cancer.org, 2017). For example, tobacco has a direct link to causing lung cancer in cancer patients if it is constantly consumed however if a person was to be surrounded by tobacco in cigarettes and not smoke it individually the possibility of cancer would be of a different level. In 2016 according to Cancer Australia, the estimated number of new cases of lung cancer was 12,203 among men and women with 8,839 men and women dying from lung cancer the same year (Australian Government, 2017). A series of changes alter the normal properties of cells, disabling the control systems which prevent cell overgrowth and invasion of other tissues, allowing them to multiply and reproduce (Alberts et al., 2017). They then develop new characteristics changing the cell structure, decreasing the ability for cells to stick together and produce new enzymes. Enzymes such as polymerase in DNA which would normally carry in the nucleotides in ‘daughter cells’ to the nucleus in mitosis (Study.com, 2017). Therefore, cancer cells easily spread and divide due to the disabling of control systems when changes occur (Learner.org, 2007). A noticeable difference between cancer cells and normal somatic cells is that cancer cells do not ‘mature’ into cell types with distinct properties and purposes hence making them less specific and allowing them in many ways to out of controllably grow and become invasive tumours (National Cancer Institute, 2016). When they develop and continue to grow and multiply the difference between a normal somatic cell and cancer cell becomes evident. As shown in Figure 2a, a tumour is formed from malignant cancer cells grouping together. The cancer cells can break away from the tumour into the blood stream and travel to another part of the body to multiply and create more tumours. This process is called metastasis and is a constant replication of malignant cancer cells and with new research developments, metastasis is beginning to possibly be stopped before cancer becomes a terminal one.
Can metastasis be stopped?
Worldwide, people are constantly wondering whether cancer can, in fact, be stopped. But with new improvements in the research of cancer cells, scientists have narrowed it down to whether metastasis can be stopped before it becomes terminal cancer. By developing processes to stop malignant tumours from spreading, medical researchers can discover improved ways to treat primary cancer before metastasis occurs. When found, metastatic cancer is known through the name of ‘primary cancer’ (National Cancer Institute, 2017). Metastasis found in other organs away from the primary tumour is the most destructive phase of cancer and remains the principal cause of death of cancer patients (Khan, 2010). A team of Stanford Researchers in 2014 began to develop a possible process to stop the spread of tumours. For cancer to spread, two proteins Axl and Gas6 interact initiating the process. The Stanford team attempted to stop metastasis by preventing these two proteins from interacting and instead replacing the Axl with a harmless version which acts as a decoy. When two Gas6 proteins combine with two Axls, the signals that are created allow cancer cells to leave the primary tumour and undergo metastasis. The decoy attaching to the Gas6 protein in the bloodstream, prevents the original linking, faking the link on cancer cells (Stanford News, 2014). This experiment was conducted on mice with aggressive breast and ovarian cancer giving them intravenous treatments of the bioengineered decoy protein. Through the treatments of the decoy protein, the mice with breast cancer showed a 78% decrease in metastatic tumours formed over untreated mice and the mice with ovarian cancer showed a 90% reduction in metastasis (Abate, 2014). Although these results are promising some limitations are still present such as the inability to test on humans due to varying reactions. Where some people may have an excellent reaction whilst others nothing at all, and hence why this breakthrough allows for more insight into the topic to begin and the stronger possibility of finding a preventative treatment to possibly stop metastasis before it becomes stage IV or terminal.
Immunotherapy & Cancer:
With new insight into the immune system and its interactions with cancer, research teams have begun to question whether the human body could be trained to fight cancer. Immunotherapy is a treatment which connects the full likelihood of the body’s natural defences being able to fight cancer and kill it (Live Science, 2017). Emerging techniques train the immune system to recognise and attack cancer as the enemy. Immunotherapy has three different types of vaccines including monoclonal antibodies, non-specific immunotherapies and cancer vaccines and each can be given in different forms including tablets or liquids consumed through the mouth, injections into a vein, a cream that can be applied to the skin and through the bladder (Cancer Australia Government, 2017). Modified viruses that attack tumour cells and prevent return have been paired with studies in immunotherapy. Recent studies show auspicious results with these new advancements have provided hope that cancer can be eventually defeated (Live Science, 2017). The immune system is trained to produce blood proteins to counteract with a specific antigen (antibodies) which neutralise the foreign cell. However, cancer cells can also produce antigens, but these antibodies don’t bind to their antigens and thus allow them to continue to grow instead of destroying them. Antibodies are normally produced by the body when harm is detected through viruses, bacteria and other substances that may cause disease. Monoclonal antibodies (mAbs) are created in a laboratory to be usually given intravenously. They are designed for many purposes including slowing growth, giving warnings to the immune system to detect and attack cancer cells and may also help transport medicines such as chemotherapy. Immunotherapies can give instruction to the immune system to produce antibodies which can attach to the antigens formed on cancer cells and prevent the function which promotes the growth of these cells or help them to recognise to destroy them through immune cells. Non-specific immunotherapies refer to the use of white blood cells which control immune responses (Cytokines) to help destroy cancer cells altogether. They are usually given whilst other treatments are occurring such as chemotherapy or radiation therapy. Types of Cytokines made include interferons, interleukins and hematopoietic each slow growth and increase production of white blood cells. Finally, there are two types of cancer vaccines preventative and treatment vaccines the difference being that preventatives fight cancer caused by disease whereas treatments prompt the immune system to fight existing cancers (Cancer Australia, 2017). The future of immunotherapies development is very important and could lead to new understandings of cancer cells. This being said, there are limitations and side effects to immunotherapy including skin reactions, fevers, low blood pressure, headaches, nausea etc. (Cancer Australia, 2017). Therefore, the human body could be trained to fight cancer through new developments in the future of immunotherapy.
In conclusion, cancer cells research has developed rapidly over time with new experiments and preventatives/ treatments being created along with possible breakthroughs in immunotherapy and stopping metastasis. The importance however of understanding the structure, function and growth and development of cancer cells is evidently important overall as well and the future of cancer which depends on a building of understanding throughout societies in the world is as well.