4. Objectives
ī Definition of Cancer and Tumor
ī Classification of cancer and tumor
ī Properties of cancer cell
ī Cancer cell VS normal cell
ī Causes of cancer
ī Signs and symptoms of cancer
ī Cell death (Apoptosis and necrosis)
ī Cancer in different organs
ī Cancer treatments
6. CANCER
ī An uncontrolled division of abnormal cells in a part of
the body is called cancer.
ī When good cells go bed.
ī Loss of Cell-cycle Control.
ī Before a cell divides, the DNA is checked to make sure
it has replicated correctly. (If DNA does not copy itself
correctly, a gene mutation occurs.
7. TUMAR
ī Tumor is an abnormal mass of tissue resulting from
uncontrolled division (cancer).
ī Tumor is of two types;
(1) Malignant tumor (cancerous)
(2) Benign tumor (non-cancerous)
8. (1) Malignant Tumor
ī Invade or spread to other parts of the body.
ī High rate of division.
ī Spread by forming Metastasis.
ī Cells travel through circulation.
ī Very difficult to treat.
9. Cancer Metastasis
ī Metastasis is the spread of cancer to other location in
the body.
ī The new tumors are called metastatic tumors, while
the original site is called primary tumor.
ī Basal lamina of epithelium normally provides barrier.
ī Malignant tumor cells break, free of attachments to
adjoining cells.
ī Attach to basal lamina.
ī Secrete enzymes that digest extracellular proteins.
ī Migrate into circulatory system.
12. (2) Benign Tumor
ī Do not spread to other part of the body.
ī Generally localized and of small size
ī Slow rate of division.
ī Cells that closely resemble, and may function, like
normal cells.
ī Do not break out of originating organ.
ī Easily to removed by surgery.
13. Classification of Cancer
ī Cancers are classified by the type of cell.
(1) Carcinoma
(2) Sarcoma
(3) Lymphoma and Leukemia
(4) Germ Cell Tumor
(5) Blastoma
14. Classification (ContâĻ)
ī (1) Carcinoma:
Cancers derived from epithelial cells.
ī (2) Sarcoma:
Cancers arising from connective tissue (i.e. bone,
cartilage, blood etc).
ī (3) Lymphoma and Leukemia:
These two classes of cancer arise from hematopoietic
(blood forming) cells.
15. Classification (ContâĻ)
ī (4) Germ Cell Tumor:
Cancers derived from pluripotent cells, most often
presenting in the testicles and ovary (seminoma and
dysgerminoma respectively).
ī (5) Blastoma:
Cancers derived from immature âprecursorâ cells or
embryonic tissue.
16. Properties of Cancer Cells
ī Cancer cells show uncontrolled mitotic divisions causing unorganised
growth.
ī Due to uncontrolled growth and division of cells, a tumor (also called
Neoplasm is generally formed).
ī They are far less adhesive than the normal cells.
ī They exhibit a number of alterations on cell surface, in the cytoplasm
and in their genes.
ī They do not undergo differentiation.
ī They lose the ability to communicate with other cells through chemical
signals.
ī They also lose sensitivity to anti-growth signals from surrounding cells.
ī They lose the adhesion molecules that keep them bonded to
neighboring cells.
ī Cancer arises from a loss of normal growth control.
17. ContâĻ.
ī Cancer is a genetic disease:
âInherited cancer
âSporadic cancer
ī Cancer typically involves a change in gene expression/function:
âQualitative change
âQuantitative change
ī lack of contact inhibition
ī Loss of limitations on the number of cell divisions
ī Ability to grow in culture (medium) â normal cells do not grow well in
culture.
ī In laboratory cultures, normal cells divide only when attached to a
surface.
ī Angiogenesis â secrete substances that cause blood vessels to grow
towards tumor.
23. Normal Cell VS Cancer Cell
ī .
Cells anchor to dish surface and
divide (anchorage dependent).
When cells have formed a
complete single layer, they stop
dividing (density-dependent
inhibition).
If some cells are scraped away,
the remaining cells divide to fill
the dish with a single layer and
then stop (density-dependent
inhibition).
25. Normal Cell VS Cancer Cell
ī Cells in culture and in vivo exhibit
contact-inhibition
ī Cancer cells lack contact inhibition
feedback mechanisms. Clumps or
foci develop.
26. Causes of Cancer
ī The great majority of cancers 90-95% cases, are due to
environmental factors.
ī The remaining 5-10% are due to inherited genetics.
28. (2) Inherited Genetics
ī Cancer is fundamentally a disease of tissue growth
regulation failure.
ī In order for a normal cell to transform into a cancer
cell, the genes that regulate cell growth and
differentiation must be altered.
ī The affected genes are divided into two broad
categories;
(i) Oncogenes
(ii) Tumor Suppressor Genes
29. (ContâĻ)
ī (i) Oncogenes:
Oncogenes are genes that promote cell growth and
reproduction.
ī (ii) Tumor Suppressor Genes:
Tumor suppressor genes are genes that inhibit cell
division and survivals.
30.
31.
32. Signs and Symptoms
ī When cancer begins, it invariably produces no
symptoms.
ī Signs and symptoms only appear as the mass continues
to grow (tumor).
34. Cell Death
ī There are two types of cell death;
ī (1) Apoptosis
ī (2) Necrosis
35. Apoptosis (Programmed Cell Death)
ī Apoptosis is a tightly regulated form of cell death, also
called the programmed cell death. Morphologically, it is
characterized by chromatin condensation and cell
shrinkage in the early stage. Then the nucleus and
cytoplasm fragment, forming membrane-bound apoptotic
bodies which can be engulfed by phagocytes.
ī Initiated by signal transduction process.
ī Does not cause inflammation.
ī Ends with fragmentation of cell into smaller bodies.
36. Necrosis (Lethal Injury)
ī In contrast, cells undergo another form of cell death,
necrosis, swell and rupture. The released intracellular
contents can damage surrounding cells and often cause
inflammation.
ī Un-programmed cell death and living tissues. (opposite to
apoptosis).
ī Initiated by direct cell damage mostly physically.
ī Cause inflammation.
ī Ends with total cell lysis.
40. Lung Cancer
īŽIn 2013, 174,470 people died from lung cancer
īŽSince 1987, more women have died from lung
cancer that breast cancer
īŽSymptoms: persistent cough, blood-streaked sputum,
chest pain
42. Breast Cancer
īŽ1 out of 8 women will develop breast cancer
(lifetime risk)
īŽ1 in 227: birth to age 39
īŽ1 in 25: ages 40-59
īŽ1 in 15: ages 60-79
īŽDetection: mammograms, regular breast self-exams
īŽSymptoms: lump in the breast, thickening, dimpling,
skin irritation, distortion or tenderness
43. (ContâĻ)
īŽRisk factors: family history, hyperplasia, long menstrual
history, obesity after menopause, oral contraceptives
īŽTreatment: lumpectomy, radical mastectomy, radiation,
chemotherapy
īŽPrevention: exercise
44. Colon And Rectal Cancers
īŽThird most common cancer in men and women with over
148,610 new cases diagnosed in 2013
īŽRisk factors: over 50 years old, obese, family history of
colon or rectum cancer or polyps, diets high in fats, low in
fiber, smoking, high alcohol consumption, lack of exercise
īŽ90% of colorectal cancers are preventable
45. (ContâĻ)
īŽTreatment: radiation, surgery, and possible
chemotherapy
īŽPrevention: regular exercise, a diet heavy in fruits and
plant-origin foods, a health weight, and moderation in
alcohol consumption
46. Prostate Cancer
īŽ Most common cancer in American men, excluding skin
cancer
īŽ In 2013, 234,460 new cases diagnosed
īŽ 1 in 3 men will be diagnosed in their lifetime
īŽ Prostate is a muscular, walnut-sized gland the surrounds
part of the urethra. Its primary function is to produce
seminal fluid.
47. (ContâĻ)
īŽSymptoms: nonspecific, weak or interrupted urine flow,
difficulty starting or stopping urination
īŽRisk factors: age, race, nationality, family history, diet,
lifestyle, and vasectomy
īŽPrevention: diet high in lycopenes, vitamin E
48. Skin Cancer
īŽLong term effects of sun exposure can result in skin cancer
īŽMalignant melanoma, deadliest form of skin cancer
īŽSun give off 3 types of harmful rays:
īŽUVA
īŽUVB
īŽUVC
īŽPrevention: limit exposure to harmful UV rays, drink
more fluids than usual, apply cool compresses to skin,
moisturize skin
49. (ContâĻ)
īŽWhat to look for â The ABCD rule
īŽ Asymmetry â half of mole does not look like the other half
īŽ Border irregularity â the edges are uneven
īŽ Color â pigmentation is not uniform
īŽ Diameter â greater than 6mm
50. Testicular Cancer
īŽAffects nearly 8,250 young men in 2013
īŽMen between the ages 15-35 are at the greatest risk
īŽImportant to practice regular testicular self exams
īŽLance Armstrong Foundation âLiveStrongâ campaign
to raise awareness
51. Ovarian Cancer
īŽFifth leading cause of cancer death for women, 20,180 new
cases diagnosed reported in 2012
īŽMost common symptom is enlargement of the abdomen
īŽRisk factors include: family history, age, childbearing,
cancer history, fertility drugs, talc use in genital area,
genetic predisposition
52. ContâĻ.
ī Prevention: diet high in vegetables and low in fat,
exercise, sleep, stress management, and weight control
53. Cervical and Endometrial (Uterine)
Cancer
īŽ9,710 new cases of cervical cancer, 41,200 cases of
endometrial cancer in 2010
īŽPap test â cells are taken from the cervical region
īŽRisk factors:
īŽCervical cancer: early age at first intercourse, multiple
sex partners, cigarette smoking, and certain STIs
īŽEndometrial cancer: age, endometrial hyperplasia,
overweight, diabetes, and high blood pressure