1/ Now we covered the DNA repair genes that validate the integrity of the DNA, we can look at the growth pathway genes that move the cell through the growth cycle into mitosis.
2/ There are two sets of genes with the Tumor Suppressor Genes and the Proto Oncogenes. The tumor suppressors act like the breaks. They are there to prevent the cell from moving through the cycle until they get a signal to allow it to do so. 
3/ The tumor suppressor genes stop movement through the cycle. Some of the most important suppressor genes work along with the DNA repair genes to ensure the DNA is ready and safe to be duplicated.
4/ These are genes like p53, p21 and Rb. The p53 gene is called the guardian of the genome as it senses signals from the DNA repair pathways and prevents cell replication unless all things are good. Any issues with the DNA will activate p53 and block cell replication.
5/ p53 is a key regulator that sits between the DNA repair pathway and the cell cycle pathways. It can arrest the cell cycle and even initiate Apoptosis which is programmed cell death. The level of p53 activation depends on the level of damage.
6/ It is shown that over 50% of all cancers have a mutation in p53 that cause a loss of function. That is what we call mutations in Tumor suppressor genes like p53 or Rb. They lose their function when they no longer work.
7/ Loss of function mutations are often where most cancers start. We get two copies of each gene. One comes from mom and the other from dad. That means you get two of the p53 and two of the Rb genes. If even one of them is working, you still have function enough for it to work.
8/ This bring us to the concept of the Two Hit Hypothesis. This means you need to lose both copies of a tumor suppressor gene to lose their function. Mutations in these gene lead to them losing function.
9/ Next are the Proto Oncogenes. They are called proto oncogenes when they are healthy. They become oncogenes when they mutate and drive cancer. These are the genes that are activated to push the cell through the growth cycle. They act like the gas peddle.
10/ It only takes a mutation in one proto oncogene to drive cancer. Many of them will work independent of any signaling staying in an always on state. This drives uncontrolled cell growth.
11/ Many of these genes we hear about all the time like RAS. Its is estimated that RAS mutations are genetic drivers in over 30% of all cancers.
12/ There are two major growth pathways in all cells that drive them through the cell cycle. These are the MAPK pathway made up of RAS, RAF, MEK and ERK and the mTOR pathway made up of PI3K, AKT and mTOR.
13/ When it comes to beating cancer, and ounce of prevention is truly worth a pound of cure. We have seen this from the annual screening programs we use today for Breast and Prostate cancer.
14/ These programs don't not prevent the formation of new cancers, but they catch them early when they can be easily treated. Early screening has save more lives in breast and prostate cancer than any single drug.
15/ Screening in Colorectal Cancer is another place where screening can catch a deadly cancer early and save lives. This is great for these indications, but many indications still have no screening tests.
16/ The liver is one of those cancers where it often goes asymptomatic until it is way too late. Being able to screen can detect early cancers in all tissues would be a game changer. This will be the biggest way to impact the survival in cancer.
17/ This is where tests like liquid biopsies and testing companies that test and track this data could play a huge role in the future treatment of cancer. Every patient that can be screened annually and detected can be treated before the cancer goes to far.
18/ We may never be able to cure cancer as its genetic mutations. The level of mutation in each cell of a single tumor is vast. The level of genetic variation from patient to patient makes curing cancer next to impossible.
19/ It takes only 1 cell to survive and the whole tumor can regrow. We may never beat cancer with a cure, but we might someday get to the point where its a non life threating chronic disease. This can be done with strong early detection and annual screening programs.
20/ Cancer might not be beaten, but it might someday be manageable.
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