Cancer & Treatments

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Benign

Tumor that forms but the cells are staying in that location

Malignant

If cells begin to break off and move away from the tumor

Metastasis

The process of cancer cells migrating through the body is called 

• During Metastasis the cells typically spread via the circulatory or lymphatic system 

• Cancer cells will end up at another location (like the liver) and form a new tumor called a secondary tumor 

Formation and spread of cancer  

• typically requires multiple changes in the cell caused by multiple mutations 

• Growth rate, anti-cancer defenses, cell adherence, cell shape 

Oncogenes

• Dominant acting 

• Onco means cancer 

• Mutation in one copy will result in cancer 

• Usually involved in sending and receiving the signal to divide 

• Normal, unmutated version is called a proto-oncogenes 

Tumor-Suppressor Genes 

• Recessive acting 

• Mutation required in both copies to have an effect 

• Usually involved in regulating or controlling cell division 

• DNA repair and detection of incorrect cell cycle 

Viruses & Cancer

• Viral integration can cause mutation in gene if that is where the virus inserts its genome 

• Human Papilloma Virus is leading cause of several cancers 

• HPV produces a growth factor that causes cells to divide rapidly 

• Additional mutations needed for cancer to spread 

• Gardasil 9 protects against HPV strands that cause cancer 

Cancer Prevention by Vaccine 

• Gardasil vaccine protects against 9 most common strains of HPV that cause: cervical, oral, throat, and penile cancers 

• Vaccine has been shown to be effective and safe 

• Decreases HPV infection by 80% and HPV-associated cancer rates by 90% in recipients 

Targeted therapy 

• Newest wave of treatments 

• Examines specific molecular differences between tumor cells and healthy cells and targets tumor-specific molecules 

• Utilizes genomics, RNA, Microarray, and 2-D gels 

Immunotherapy 

Aids patient’s immune system in fighting cancer cells 

• Cell amplification 

• Monoclonal antibody treatment 

• Transfusion of Interleukins 

Radiation Therapy

• Often used in conjunction with surgery 

• Causes DNA damage in targeted cells 

• Relies on diminished DNA repair in many tumors 

• Bombardment puts healthy cells at risk 

• Can cause mutations in healthy cells 

New technology is better at targeting tumor more precisely: 

• Proton scalpel technology 

Chemotherapy

• Drugs target differences between cancerous calls and normal cells (Growth Rate, DNA Repair, Vascularization) 

Serious Side Effects 

• Window to target is sometimes narrow 

• Chemotherapeutics are essentially toxins 

• Precise dosage is essential 

• Normal but fast-replicating cells can be damaged (Hair Follicle Cells) 

Surgery 

• Most useful for benign tumors 

• If entire tumor is removed cancer could be cured 

• Limited by location of tumor 

• If tumor is malignant even removing primary tumor would not prevent spread of secondary tumors 

• Surgery is often coupled with other treatments 

Causes of Cancer: Mutation 

• Higher mutation rates mean higher likelihood of developing cancer 

• Most mutations occur as mistakes in replication (that are not corrected) 

• UV radiation: leading cause of skin cancer 

• Dose makes the poison 

Causes of Cancer: Age 

• Greater risk at age 45+ 

• Due to accumulated risk of a replication error or repetitive exposures to mutagenizing agents 

• Childhood cancers still occur but success rate of treatments is very good 

Causes of Cancer: Radiation 

• Naturally occurring radiation is most of the problem 

• UV radiation from the sun 

• Radon gas in soil 

• Cosmic rays and gamma rays from space  

Causes of Cancer: Chemical Agents

• Some chemicals can cause mutations by directly interacting with DNA (These are Dangerous) 

• Others can cause reactions that produce secondary molecules that can damage DNA 

• These are more common 

• Actual risk all about the relative risk and exposure levels