Differences between Normal Cells and Cancer Cells
Normal Cells will be divided in a
structured way in order to produce more cells only when the body needs them
where as with regards to cancer cells, more cells will be created continuously
without any control. Sometimes, a mass of the tissue will be created, which is
also called as tumor. Normal cells derive 20 percent of their energy from a
system called ‘Glycolysia’ and 70 percent of energy from a system called ‘Kerb
Cycle’. Cancer cells derive nearly 99.9 percent of energy from the system
called ‘Glycolysia. Oxygen is the main source of energy for normal cells where
as cancer cells will derive most of their energy without oxygen. Normal cells
will have a built-in blood vessel system where as cancer cells do not. Cancer
cells need amino acids to build blood vessel system. The growth of normal cells
is very normal and completely in control where as cancer cells will be hyper
active in their growth. Enzymes and hormones behave in a balanced manner in
normal cells where as enzymes and hormones behave either hyper active or under
active in cancer cells (Dingli and Nowak 2006).
Which type of cancer shows the most aggressive
growth? Explain.
Small Cell Lung Cancer (SCLC) shows most
aggressive growth when compared to other dangerous cancers. The survival time
for the patients who are suffering from the small cell lung cancer is nearly 3
to 4 months after diagnosis when untreated. Most of the small cell lung cancer
cases are due to smoking and it is not really common in people who do not
smoke. SCLC is more common in men than women and nearly 15 percent lung cancer
patients are suffering for small scale lung cancer. SCLC starts at the center
of the chest in the breathing tubes. Though, the cells are very small, they are
very dangerous and effective in reproduction and growth. If these small cells
crate a mass tissue, it will be immediately turned as a tumor. Small cell lung
cancer can spread across the body very quickly. The major target areas for this
kind of cancer are liver, brain and bone. Chemotherapy will be used to prolong
the life of the patient that suffers from SCLC. The combination of chemotherapy
and other methods can prolong the life of the patient up to 4 years. When
suffering from SCLC, the chances of living for more than 5 years after the
diagnosis are only 4 percent (Rosti, Bevilacqua
and Bidoli March 2006).
Which type of tissue would have a higher mitotic
index, normal tissue or cancerous tissue? Explain.
Mitotic index is used to calculate the
ratio between the number of normal cells or total number of cells or between
the number of cancer cells and total number of cells in the body. Mitotic index
purely depends on the reproduction capability of the cells. If the reproduction
capability of a particular cell is high, the mitotic index for that cell will
also be very high and vice-versa. The mitotic index for cancer cells is higher
than normal cells because cancer cells can reproduce their cells uncontrollably
with their hyper active growth nature. The main reason behind large
reproduction is high mutation of DNA in cancer cells. As per experts, the
percentage normal cells dividing in normal tissue is 5 percent whereas in a
cancerous lung tissue the percentage is around 25. Other reasons behind high
mitotic index in cancer cells is unstructured way of cell creation, hyper
active enzymes and hyper active hormones (Baak et al. (2008).
References
Baak, J. P. A.; Gudlaugsson,
E.; Skaland, I.; Guo, L. H. R.; Klos, J.; Lende, T. H.; Søiland, H. V.;
Janssen, E. A. M. et al. (2008). "Proliferation is the strongest
prognosticator in node-negative breast cancer: Significance, error sources,
alternatives and comparison with molecular prognostic
markers". Breast Cancer Research and Treatment 115 (2):
241–254.
Dingli D, Nowak MA (September
2006). "Infectious
Cancer Cells". Nature 443 (7107): 35–6.
Rosti, G; Bevilacqua G, Bidoli
P et al. (March 2006). "Small
cell lung cancer". Annals of
Oncology 17 (Suppl. 2): 5–10.
