How Cancer Develops
Cancer is a
medical condition characterized by uncontrolled multiplication of a group of cells leading to formation of a
malignant tumor. At the genesis, the tumor remains
located and causes no symptoms. But without early detection and treatment, it will gradually invade the organ
in which it was born, altering its functioning, and possibly spreads to distant organ; this is
called metastatic cancer.
The Difference between Healthy
Cells and Cancer Cells
Healthy cells multiply in a controlled
manner. They divide at normal interval and are not programmed to reproduce a number of times over without
dying. When the division reaches its limit or
when the cells are too old and present alterations that cannot be repaired, they die to be replaced by new
healthy cells. This is a form of natural rejuvenation system that keeps living beings healthy.
Our body is equipped with
a natural system which enables healthy cells to detect DNA damage and repair it as soon as possible.
When an abnormality is found, cell
division is momentarily stopped to allow cellular repair. If the damaged cells cannot be repaired,
the cells trigger their own suicide, a biochemical event called
The normal functioning of
the body is impacted when DNA damages affect the system responsible to this process. That is, if mutations
occur in genes required for the detection of abnormalities or trigger the programmed cell suicide, the
diseased cells will continue to divide.
This is the first step in the
transformation of a healthy cell into a cancer cell.
Cancer arises from
healthy and functional tissues that have become abnormal due to damage in their cell DNA. These mutations cause a disruption or
malfunctioning, leading to inactivation of the systems that normally control cell
division. The cells then become malignant and
start proliferating uncontrollably (cancer). During the alterations, the patient feels nothing abnormal. The
body, the immune system, usually fights the pathogenic attacks to prevent the disease form developing. If,
unfortunately, it is too weak to overcome the cancer, it starts developing. This is why some researchers say
“cancer is a disease of the immune system”.
Cancer cells reproduce in an ‘out of control’ manner
without normally dying. With no proper treatment, these cells
can divide indefinitely, thus leading to fetal complications. They have, in addition, the ability to
induce the formation of blood vessels that will provide oxygen and nutrients necessary for their
multiplication. As the disease progresses, some cancer
cells will detach from their original site to migrate elsewhere in the body and lead to the formation of
secondary tumors. At this stage, the cancer is advanced and survival becomes more difficult.
How Damage to Cell DNA
A variety of factors can cause DNA
damage. For instance, exposure to mutagenic substances, natural or artificial, can lead to lesions in the DNA
of our cells. This may be of industrial chemicals or
else such as those found in foods (GMO), water (fluoride), tobacco smoke, alcohol, ionizing radiation
(radioactivity), viruses (HPV), or bacteria ( Helicobacter pylori). The list is
enormous; this is just a few.
Genetic Predisposition to
This is a very
controversial topic; some scientists believe in genetic predisposition to certain cancers, others believe the
reason some cancers run in family is because lifestyle tends to be transmitted from one generation to
another; therefore, genetic has nothing to do with cancer. Some people are born with one or more lesions
already present in their genetic heritage, often transmitted by their parents. These people have a higher risk than the
general population of developing cancer due to the fact the transformation of their cells has already begun
at birth; what it is called genetic predisposition to cancer.
In addition to
these cancers above, it is found that mutations in either BRCA1 or
BRCA2 can lead to hereditary breast–ovarian cancer syndromes (HBOC), which can cause the development of breast cancer and ovarian cancer. It is also believed that genetic
prediction can increase the risk of individual to have male breast cancer, kidney cancer, or colon cancer. But even when it is the case, “only about 5% to 10% of
all cancers result directly from gene defects (called mutations)
inherited from a parent.”
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