Biochemistry from Dr. Dhiraj J Trivedi SDM College of Medical Sciences and Hospital, Dharwad, India

1. Cancer
Neoplasia
Dr. Dhiraj J Trivedi

2. •Cance r
Cance l
•Mutation ?
•Mute action

3. What is tumor?
• Excessive,
• abnormal,
• unwanted,
• uncontrolled
• purposeless multiplication of cell
Benign
•Encapsulated
•No spread
Malignant
•Spreads
•Non capsulated

4. What is growth ?
• Cells are the building blocks of living
things.
• Normal cells multiply
• when the body needs them for growth.
• and die “apoptosis”
• when the body doesn't need them.

5. What is growth ?
• Cancer grows out of normal cells in the body.
• The growth of cells in the body is out of
control
• Cells divide too quickly.
• And when cells “forget” how to die.

6. What is Cancer ?
• Excessive , uncontrolled proliferation
and
• spread of cells due to loss of control
over cellular growth and cells “forget”
how to die.
Alternative Names :
Carcinoma; Malignant tumor, Neoplasia

7. Cancer ?
Epithelial cell
•Carcinoma
Connective tissue
•Sarcoma
Oncology = Science deals with
Study of cancer

8. What are the characteristics of
Cancer cells?
• Uncontrolled growth
• Invasion of local tissue
• Spread or metastasis to other parts of body
• Abnormal in structure
• Abnormal in metabolism
• Forget how to die “APOPTESIS”

9. Why to study
Biochemistry of cancer?
• Second most common cause of death
• All ages are susceptible
• Wide variety of organs involved.
• Economic burden to society

10. What are the causes?
• Physical -- Radiant energy (UV, X-ray, -ray)
• Chemical -- Organic or inorganic
• Biological -- Viruses

11. Physical Agents
• UV, X-ray, -ray are mutagenic
• They target DNA and damage it
• They cause free radicals formation in tissue
which can also cause DNA damage

12. Chemical carcinogens
• Responsible for 80% of the cancers
• They are mutagens
• But nothing is common to understand
Chemical Group Examples
Polycyclic aromatic
hydrocarbon
Benzopyrene
Diemthyl ben anthracene
Aromatic amines 2- Acetyl amino fluorene (2AAF)
Nitrosamine Dimethyl nitrosamine
Diethyl nitrosamine
Drugs Cyclo phosphamide
Diethyl stilbesterol
Inorganic compounds Arsenic, Asbestoes,
Cadmium, Chromium , Beryllium

13. Are We inviting cancer ? --
YES
80% of cancers are out comes of environmental
chemicals created by human
• Due to occupation –
• (benzene, vinyl chloride, asbestos, cement, organic dye,
tobacco industry)
• Diet --
• (aflatoxinsB1 produced by mold)
• Life style --
• (Smoking and eating tobacco, Alcohol )

14. How do these chemical become
carcinogens?
Pro-carcinogens
At least two Transformations
Potent Carcinogens

15. Carcinogens divided into 2
stages
Initiation
• Causes irreversible
modification of DNA
• Chemicals are called
initiating agents
Promotion
• Responsible for
Progression of
cancer
• Promoters
• promoting agents
• can not initiate
process

16. Main target is DNA
molecule
• Proto-Oncogenes :
• Normal gene present in the cell, only on
damage get converted to Oncogenes.
• Oncogenes :
• Transforms normal cell to tumor cell,
capable of causing cancer.

17. DNA and RNA viruses
DNA
Papova virus Polyoma virus SV40
Papilloma virus
Adeno virus Adeno virus 12, 18,,31
Herpes virus Epstein Barr,
Herpes simplex type 2
Pepadna virus Hepatitis B virus
RNA
Retro virus
type C
Murine sarcoma, Leukemia virus
, Avian sarcoma
Type B Mouse mammary tumor virus

18. What happens to the cell on
malignant transformation?
• Morphological
change
• Much rounder cells
• Loss of contact inhibition
of growth (forms
multilayer )
• Loss of anchor
dependence (grow
without attachment)
• Loss of contact
recognition (Spread )
• Altered permeability
• Altered surface charge
• Biochemical changes
• Increased synthesis of DNA
and RNA
• Increase rate of Glycolysis
• Decreased pyrimidine
catabolism
• Change in Glycoprotein and
Glycolipid molecule on surface
• Decreased requirement for GF
• Altered secretion of
proteases and isoenzymes
profile
• Loss of certain Antigenic
molecules

19. Is it possible to detect ?
-- YES
• Abnormal enzymes, proteins and
hormones produced by tumor cell can
be measured in plasma / serum.
• Biochemical indicators employed to
detect the presence of cancers are
called ---
“TUMOR MARKERS” or “BIO-
MARKERS”

20. Tumor markers associated with cancer
Marker Associated cancer
Carcinoembryonic
Antigen (CEA)
Colon , Lungs, breast,
pancrease
Alfa Feto Protein (AFP) Liver, germ cell
Human Chorionic
Gonadotrophins (hCG)
Trophoblast, Germ cell
Calcitonin (CT) Thyroid
Prostatic acid Phosphatase
(PAP)
Prostate
Prostate Specific Antigen
(PSA)
Prostate
Alkaline Phosphatase (ALP) Bone

21. A short out line for 5 marks
Thank you