‫‪By :‬‬
‫سلمى المطيري ‪0877054‬‬
‫مها العمري ‪0874150‬‬
‫خلود الحيدري ‪0877180‬‬
‫ساره األسمري ‪0874064‬‬
‫‪0746355‬‬
‫سماح عالم‬
‫اشواق الفارسي ‪0873062‬‬
What is Cancer
Cancer is a disorder of Cells , a Class of in creases of a group of cells
display uncontrolled growth ( division beyond the normal limits ) .
Although it usually appears as a tumour ( a swelling ) made up of a mass
of cells , the visible tumour is the end result of whole series of changes
which tare many years , to develop .
The medical team is malignant neoplasm .
Invasion is intrusion on and distruction of adigacent tissues .
Metastasis is the spread of tumour to other locations in the body Via lymph or
blood and the new tumours that appears for from the original tumour .
Tumour is Called neoplasm described as abnormal proliferation of geneticaly
altered cells .
Oncology is the branch of medicine .
Concerned with the study , diagnosis , treatment an prevention of cancer.
Cancer is Classified according to the tissue it originated from .
It includes :Carcinoma : A malignant tumour of epithelial tissues represent most
Common Cancer such as Cancers of the breast , prostate , Lung
and Colon .
Sarcome : A malignant tumour of mesenchma and connective tissues .
Lymphome and leukmia are Cancer of hematopiotic blood forming
cells .
Lymphoma is a solid tumour of T and B lymphocytes e . g .
In the lymph nodes , thymus on spleen .
4 ) germ Cell tumour :
In adults Found in the testicals and ovaries . In fetus , babies and
young Children most Common in Children .
Benign tumour : Does not invade or metastasize .
it is a self limited tumour .
In Situ tumour : Develop in epithelial layer .
Malignant tumour Capable of invading
surrounding tissue and metastasizing .
Divide into four Main groups :
A ) The mesenchyma consists of connective tissue fibroblast
which makes collagen fibers and associated proteins , bones
, cartilage ,muscles , blood vessels and lymphatics .
b) The epithelial cells : Are the specific cells of the different
organs e.g. skin ,intestine , liver , glands et .
c) The reticleoendothilial system Consists of a wide group of
Cells mostly derived from precursor cells in the bone
marrow which give rise to all the red and white blood cells .
Some are distributed ( lymphocutes and macro phage )
through the body either as free cells or organs such as the
spleen and lymph nodes .
d ) The nervous system ( brain and spinal ) their coverings and
the peripheral nervous system leading from these central
structure .
Cancer Causes .
Environmental (see later )
Genetic change in DNA sequence .
Epigenetic .
Genetic of Cancer .
Oncogenes : protooncogenes present in all human
changes to Oncogenes Causing Cancer in some
people .
Tumour suppressor genes present in all humans ,
prevent tumour formation , they are silent in some
people .
Cancer Causes
Environmental :
Chemicals
Radiations
Pollutants
Genetic Factors
Genetics of Cancer
Oncogenes
Tumor Suppressor genes
Protooncogenes Present in all
Presesnt in all humans , prevent
Humans , get sweitched on in Some
tumor , but are Silenced in some
People Causing Cancer
People Causing Cancer .
Carcinogenesis is a Multistage process
Initiation and Promotion
Initiation starts when there is an application of
Cancer producing a gent ( carcinogen ) . Initiated
cells remain latent until acted Upon by promoting
agents . Transformed Cells may not grow at all or
grow very slowly .
Promoting a gent are not carciogenic in themselves
but they induce cells to divide and initiate tissue .
Many agent may induce cell division but only
promoters will induce tumour development .
Fig : Factors Influencing tumour development .
Second Step or Stage : Is the tumour promotion
produced by the carcinogen or other Substances (
Promoting agent ) which do not produce tumours .
Initation however is the primary and central step in
the process , very rapid but once the initial
Changes has taren Place the initiated cells may
Persist for a considerable time , perhaps the
lifespan of the individual the site for the primary
Event is in the Genelic Material ( DNA ) .
The carcinogen damage or destroy specific gene
i.e. The DNA OF CELLS FROM THE STEM CELL
POPULATION OF TISSUE INVOLVED .
Increase cell division .
Increase cell growth .
Cause mutations .
Affect cell Signaling .
Destroy error Correcting mechanisms .
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

lncreased cell division: Some Carcinogens Cause
increased cell division rates and lead to formation
of tumors .
Increased cell growth: Some carcinogens arrest the
cell cycle at the " growth Phase . leading to
increased cell growth –and ,abnormal ;cell cycles,
Mutations: Mutations are abnormalities in cells
due to various agents Mutated cells lose the ability
to function normaily and can turn into cancerous
cells .
Affecting cell signalling
All normal cells receive specific signals that trigger progrnmmed cell death
Some chemicals destroy these signals
As a result the cells do not receive the signals that start cell death Hence they
keep growing causing cancer
Destruction of error repair mechanisms :
Every normal cell has DNA repair genes .
These genes correct any defects that occur sometimes during DNA replication
and cell growth in normal cells.
UVR AND REP GENE .
These genes are calleduvr and rep gene
Some Carcinogens affect the repair genes .
As a result, these genes do not function and do not correct errors in the cell,
leading to abnormal growth, division and cancer .
Tumor cells display characteristic set of features that
distinguish them from normal cells.
These traits allow the individual cells to form a tumor
mass and eventually to metastasize to other parts
of the body .
A wide range of changes occur during the
transformation of a normal cell to a cell capable of
forming a cancerous growth.
All cancer cells acquire the ability to grow and divide
indefinitely.
There are also detectable changes in the physical
properties of the cells.
1-Cytoskeletal changes: The distribution and activity of the microfilaments and
microtubules may change. These alterations change the ways in which the cell
interacts with neighboring cells and alter the appearance of the cells. Changes in
the cytoskeleton also affect cell adhesion and movement (motility).
2-Cell adhesion / motility: The reduction of cell, cell adhesion allows large masses
of cells to form.
Cancer cells don't exhibit contact inhibition and are able to continue to grow even when
surrounded by other cells.
The alterations in cell adhesion also impact on the ability of the cells to move.
Cancer cells must be able to move and migrate in order to spread and cell adhesion
plays a major role in regulating cell movement.
3-Nuclear changes: The shape and organization of the nuclei of cancer cells may be
markedly different from that of nuclei of normal cells of the same origin.
This change in appearance may be useful in the diagnosis and staging of tumors.
4-Enzyme changes: Cancer cells often secrete enzymes that enable them to invade
neighboring tissues.
These enzymes digest away the barriers and spread of the tumor cells.
The growth of a tumor from a single genetically altered cell is a stepwise
progression.
The process described below is applicable for a solid tumor such as a carcinoma
or a sarcoma.
Blood cell tumors go through a similar process bit since the cells are freefloating they are not limited to one location in the body.
1-Hyperplasia: The altered cell divides in an uncontrolled manner leading to an
excess of cells in that region of the tissue. The cells have a normal
appearance but there are too many of them.
2-Dysplasia: Additional genetic changes in the hyperplastic cells lead to the
even more abnormal growth. The cells and are tissue no longer look normal.
The cells and the tissue may become disorganized.
3-Carcinoma in situ-: Additional changes make the cells and tissues appear
more even abnormal.
The cells are now spread over a larger area.
The cells often "regress" or become more primitive in their capabilities. An
example would be a liver cell that no longer makes liver-specific proteins.
Cells of this type are said to be de-differentiated or anaplastic.
A key facet of in situ growth is that the cells are contained within the initial
location and have not yet crossed the basal lamina to invade other tissues.
Cancer of this type are often totally curable by surgery since the abnormal cells
all in one location.
Tumors of this type have not yet invaded neighboring tissue.
1) Resemble their tissue of origin .
2) Every tissue components not involved .
3) Cells may or may not be in their normal
relationship .
4) Arise in most tissues .
5) Increase in size .
6) Do not invade
7) Separated from the surrounding tissue by a
capsule of connective tissue .
8) The tumour cells do not differ from normal
organ cells .
9) Bone or cartilage may produce nodules of bone
or cartilage indistinguishable from the normal
tissue .
10) Local benign tumours are made up of all
tissues component from groups of cells in
epithelial tissues .
11) The lining tissues of skin, intestinal, bladder,
etc. may form wart-like out growths containing
all the tissues components but closely packed
to form a solid nodule .
12) Local wart is a local out growth .
13) In other situation only one costituent will give
rise to a benign tumour .
14) Do not invade but may increase in size and
press on and damage the remaining normal
cells .
Benign Epithelial Tumour :
Arise in many other organs . Has different tubular
pattern . Lined by several different epithelial
cells and surrounded by connective tissues. i.e.
kidney, breast made up of tumours struct .
1 )cellular abnormalities (some times slight)
2) lnvasion of surrounding number.
3)local increase in cell number.
4)loss of the normal regular arrangement of cells.
5)variation in cell shape and size.
6) lncrease in nuclear size (increase in DNA)
7) lncrease in density of the staining (Reflect
increase of DNA)
8) lncrease of mitotic activity (cell division)
9)Abnormal mitosis and chromosomes.
1)tumours of Epithelium
Bening from squamous epith papilloma
malignant carcinoma from epithelium either
squamous cell carcinoma or basal cell
carcinoma of the glands adeocavcincma
2)tumour of mesenchyme
Benign fibrome fiber tissue
Osteoma bones
Angiomas blood vessels
Malignant tumor
Mesenchyma sarcoma osreosarcoma (bones)
Bening:multicentric origin
Malignant:leukamia from blood forming cells.
Lymphomas arising from fixed cells
4)Tumours of nervous system:
Most sre malignant tumours hardiy ever spread.
-Neuroblastoma from the neuron .
-Retinoblastomas from the retina.
5)Tumours from mixed tissues contain a whole range of different
tissues
They are rear.
May be benign but most are malignant.
Tetratomas arise from primitive cells of embryonic type (in the
testis
And ovaries).
T umour Metastasis major problem . Tumour
staging used to give an assessment of spread of
tumours.
The internatioal Union against cancer system or
TNM system.
T assessment of primary tumour.
N the regionl lymph nodes.
M the presence or adsence of metastasis.
Each is qualified by a number which indicates the
precise extent of involvement according to
clearly defined criteria.
Can be diagonsed if they produce some effects
Which can be easily examined(skin breast)
Tumour cell die and release enzyme which damage the
tissues non healing ulcer
May be formed. Blood vessels at the base of the ulcer are
damage causing bleeding
In the bowl may cause obstruction or bleeding tumour of the
brain causes headache due to pressure inside the skull
from the bite may cause jaundice may causes hormonal
effect particularly those which arise from hormone
producing organ either by continuing to produce an
excess of the hormones which the normal organ produce
or causing hormone deficiency by damaging the
remaining normal gland cells or may produce abnormal
hormones of hormones may be produced in tumours of
organ which do not normally produce these substances
S phase – Synthesis ;
The ensuing S phase starts when DNA synthesis commences; when it is
complete, all of the chromosomes have been replicated, i.e., each
chromosome has two (sister) chromatids.
Thus, during this phase, the amount of DNA in the cell has effectively doubled.
Rates of RNA transcription and protein synthesis are very low during-this
Phase .
G2 phase:
The cell then enters the G2 phase , which lasts until the cell enters mitosis.
Again, significnt protein synthesis occurs during this phase,mainly involving
the production of microtubles which are required during the process of
mitosis .
Inhibition of protein synthesis during G2 phase prevents the cell from
undergoing mitosis .
Mitosis ( M Phase )
The relatively brief M phase consists of nuclear division (karyokinesis) and
cytoplasmic division (cytokinesis).
The M Phase has been broken down into several distinct phases phases ,
sequentially known as prophase prometophase , metaphase , anaphase
and telophase leading to cytokinesis .
Mitosis is the process in which Eukaryotic Cell separates the chromosomes in
its cell nucleus into two identical sets in two daughter nuclei.
It is generally followed immediately by cytokinesis, which divides the
nuclei, cytoplasm, organelles and Cell membrane into two daughter Cells
containing roughly equal shares of these celluar components .
Mitosis and cytokinesis together define the mitotic (M) phase of the cell cycle
the division of the mother cell into two daughter cells, genetically identical
to each other and to their parent cell .
M
G2
G1
S
At the centre of ( cellular proliferation) is the cell division cycle, the
process by which a cell grows . replicates its DNA and then divides
to give two daughter cells .
This process is divided into four sequential phases :
It is often. Considered that the two most important of these are S phase
when DNA replication occurs and mitosis ( also Know as M phase),
when the cell undergoes division to give two daughter cells .
In facta key concept of the cell cycle is that S phase must always follow
M phase and that M phase must not start unril S phase has been
completed . In Other words ,
DNA replication must not commence until mitosis is Complete and
mitosis must not begin' until the previous round of DNA replication
has ended.
G2
Tumour Angiogenesis
IT IS THE FORMATION OF NEW BLOOD VESELS .
Tumour Angiogenesis is the proliferation of a network of blood vessels
that penetrates inside the cancerous growth to supply nutrients and
oxygen and to Remove the waste products .
Tumour Angiogenesis Actually Releasing to the surrounding Noraal host
cells .The signals usually Activates certain genes in the host tissues that in
turn synthesize proteins to encouragegrowth of new blood vessels .
F 3 : Tumour Angiogenesis .
ANGIOGENESIS OCCURS IN HUMAN, Body At Specific times in
development and growth .
In mother uterus developing the network and
capillaries that are Developed After wards in
human body . After wards angiogenesis changes
( REMODULE ) this network into the small new
blood vessels or capillaries that forms the
circulating system of the child . New blood
vessel Proliferation Also occur in adults but
relatively infrequent .
ANGIOGENESIS IS NECESSARY FOR :
Repair or Regeneration of tissues During wound healing .
In women it is Active few days Each month as new blood
vessels form in the uterus lining during the menstrual
cycle.
Angiogenesis is controlld by both Activators and inhibitors.
Inhibitors are usually Predominating , blocking
more growth .
Activators increase in number and inhibitors
decrease when a need for new blood vessels arises .
this promotes growth and division of vascular
endothelial cells and ultimately the formation of
blood vessels new.
Activators of Angiogenesis or Angiogenic :
There are more than twelve different proteins as
well as several smaller molecules
Angiogenic Means that they are relased by
tumours as signals for angiogenesis .
Growth Factors for Angiogenesis :
There are two growth factors :
-Vascular Growth Factor VEGA .
-Basic Fibroblast Growth Factor BFGF .
The Angiogenesis Signaling cascade:
a) First VEGE and BFGF are
synthesized inside tumor cells then
secreted into this surrounding
tissues.
b) VEGF and BFGF encountered
endothelial cells and bind to their
cell receptors found on the outer
surface of the cells .
c) This activates a series of
proteins which transmits a signal
into the nucleus of the
endothelial cells.
d) The nuclear signals to
synthesize products needed for
new endothelial cell growth.