This document discusses cancer, including its causes, characteristics, types, detection, and treatment. Some key points: - Cancer is caused by uncontrolled cell growth and can be due to physical, chemical, or biological carcinogens. Common types include carcinomas, sarcomas, melanomas, lymphomas, and leukemias. - Cancer cells lose contact inhibition and cell adhesion, allow angiogenesis and metastasis. Oncogenes and tumor suppressor genes like p53 can contribute to uncontrolled growth. - Detection methods include biopsies, blood tests, imaging like CT/MRI, and monoclonal antibody tests. Molecular techniques can identify inherited cancer risks. - Common treatments are surgery to remove tumors, radiation therapy

1. NON-INFECTIOUS
DISEASE
‘Cancrum’ – Crab
An uncontrolled division or
proliferation of cells without
any differentiation.

2. CANCER
• Cancer is one of the most dreaded diseases of
human beings and is a major cause of death
all over the globe.
• More than a million Indians suffer from
cancer and a large number of them die from it
annually.
• The mechanisms that underlie development
of cancer or oncogenic transformation of
cells, its treatment and control have been
some of the most intense areas of research in
biology and medicine.

4. TYPES OF CANCER
1. Carcinoma – Epithelial tissue cancer (lung
carcinoma, breast carcinoma, colon
cancer, stomach cancer, oral cancer etc).
2. Sarcoma – Connective tissue cancer
(osteosarcoma).
3. Melanoma – Skin cancer
4. Lymphoma – Lymph gland cancer
(Burkitt’s lymphoma, Hodgkin disease).
5. Leukemia – Cancers of the W.B.C.

5. • Uncontrolled division - In our body, cell growth and
differentiation is highly controlled and regulated. In
cancer cells, there is breakdown of these regulatory
mechanisms.
• Loss of contact inhibition - Normal cells show a
property called contact inhibition by virtue of which
contact with other cells inhibits their uncontrolled
growth. Cancer cells appears to have lost this
property. As a result of this, cancerous cells just
continue to divide giving rise to masses of cells
called tumours or neoplasm.
Characteristics of cancer cell

6. • Loss of cell adhesion – Cancerous cells break out or
slough off from their source of origin or primary
tumour.
• Angiogenesis
New blood vessel
formation .
• Metastasis -
Characteristics of cancer cell

7. Property of cancer cell
Metastasis – The tumour cells grow very
rapidly, invading and damaging the
surrounding normal tissues. As these cells
actively divide and grow they also starve
the normal cells by competing for vital
nutrients. Cells sloughed from such tumours
reach distant sites through blood, and
wherever they get lodged in the body, they
start a new tumour there. This property
called metastasis is the most feared property
of malignant tumours.

9. Tissue can be organized in a continuous spectrum
from normal to cancer

10. TYPES OF TUMOUR
Tumours are of two types:
Benign and Malignant
• Benign tumours normally remain confined to
their original location and do not spread to
other parts of the body. They cause little
damage to the body.
• Malignant tumours are a mass of
proliferating cells called neoplastic or tumour
cells. These grow rapidly, invade and
damages the surrounding normal cells and
tissues.

11. CAUSES OF CANCER
Transformation of normal cells into cancerous
neoplastic cells may be induced by physical, chemical
or biological agents called CARCINOGENS
1. Physical agents –
 Ionising radiations like X-rays and gamma rays
 Non-ionizing radiations like UV cause DNA damage
leading to neoplastic transformation.
2. Chemical agents /carcinogens present in tobacco
smoke have been identified as a major cause of
lung cancer, benzene, fumes etc.
3. Biological agent - Viral oncogenes - Cancer causing
viruses called oncogenic viruses have genes called
viral oncogenes.

12. Oncogenes
• The generic name ‘oncogene’ is gene capable of causing
cancer. Oncogene comes from the Greek word Onkos =
mass or tumor.
• Oncogenes are mutant versions of normal genes
(sometimes called proto-oncogenes) that drive cell growth.
• Several genes called cellular oncogenes (c-onc) or proto
oncogenes have been identified in normal eukaryotic cells
that are thought to regulate normal cell growth and
development like -
† c – abl
† c – myc
† c – ras
• Oncogenes when activated under certain conditions, could
lead to oncogenic or malignant transformation of the cells.

13. Tumour Suppressor genes
• Rb gene - In humans, the protein is encoded by
the RB gene located on chromosome 13. It codes
for a protein that functions as a “master brake” in
the cell cycle.
• P 53 gene - The human p53 gene is located on the
chromosome 17. P53 has been described as
"the guardian of the genome", referring to its role
in conserving stability by preventing genome
mutation.
• BRCA1, BRCA2 gene – In human, it is located in
chromosome 17 & 13 respectively. Two
different genes have been found to impact a
person's chances of developing breast
cancer. Mutation leads to breast cancer.

14. Cancer Detection & Diagnosis
Early detection of cancers is essential as it allows
the disease to be treated successfully in many
cases by the following methods -
1. Blood and bone marrow test - Cancer detection
is based on blood and bone marrow tests for
increased cell counts in the case of leukemia.
2. Biopsy – of a piece of the suspected tissue is
done by cutting thin sections, then staining and
examining under microscope (histopathological
studies) by a pathologist.

15. Detection of Cancer
Techniques like radiography, CT and MRI are very
useful to detect cancers of the internal organs.
3. Radiography – by X rays to detect cancer.
4. Computed tomography (CT) uses X-rays to generate
a three-dimensional image of the internals of an
organs.
5. Magnetic resonance imaging (MRI) uses strong
magnetic fields and non-ionising radiations to
accurately detect pathological and physiological
changes in the living tissue.
6. Monoclonal antibodies against cancer specific
antigens are also used for the cancer detection.

16. Molecular Biology techniques in cancer
detection
• Such techniques can be applied to detect genes in
individuals with inherited susceptibility to certain
cancers.
• Identification of such genes, which predispose an
individual to certain cancers, may be helpful in
prevention of cancers.
• Such individuals may be advised to avoid exposure to
particular carcinogens to which they are susceptible
(e.g. tobacco smoke in case of lung cancer).
Detection of Cancer

17. Treatment of cancer
The common
approaches for
treatment of most
Cancers are -
1. Surgery
2. Radiation
therapy
3. Chemotherapy

18. Treatment of cancer
• Surgery – Tumour
cells are surgically
removed.
• Radiotherapy -
tumour cells are
irradiated lethally,
taking proper care of
the normal tissues
surrounding the
tumour mass.

19. • Chemotherapy -
Chemotherapeutic drugs
are used to kill cancerous
cells. Some of these are
specific for particular
tumours. Majority of
drugs have side effects
like hair loss, anaemia,
etc.
Treatment of cancer
Combination therapy – Most cancers are
treated by combination of surgery,
radiotherapy and chemotherapy.

20. • Immunotherapy - involves use of biological
response modifier like α-interferon which activates
immune system to detect the cancer cells & destroys
them.
Treatment of cancer