1. Leukemia is a cancer of the blood and bone marrow characterized by an abnormal proliferation of white blood cells. It was first discovered in 1845 by Rudolf Virchow who noticed a high number of white blood cells in a patient's bloodstream. 2. There are two main types of leukemia - acute and chronic. Acute leukemia progresses rapidly with less than 20% mature white blood cells while chronic leukemia progresses more slowly with more mature white blood cells. 3. The main types are acute myeloid leukemia, acute lymphoblastic leukemia, chronic myeloid leukemia, and chronic lymphocytic leukemia which are distinguished by the specific cells that are affected.

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2.  Name: Abdul Qader
 Medical lab Technologist
 Rehman college of Allied Health Science
 Email: qadarkhan260@gmail.com
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3. Topic:
Molecular biology of leukemia
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4. History
 Rudolf Virchow, a German biologist discovered leukemia in
1845. while performing an autopsy , he noticed a high number
of white blood cells in the dead body person’s bloodstream.
For this condition, Virchow suggested the Greek name
leukemia, which means “White blood”.
 The term “ Myeloid “ was invent by Franz Christian Neumann
in 1869
 1900- Otto Naegeli who divided the leukemia into myeloid
and lymphoid steps
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5. Words Abbreviation
N-ras gene Neuroblastoma RAS gene
RB1 gene Retinoblastoma 1 gene
Tal-1 T-cell acute lymphocytic leukemia 1
Ttg-2 Tissue transglutaminase 2
HOX-11 Homeobox-11
ABL Abelson
BCR breakpoint cluster region
Bcl-1 gene B-cell lymphoma gene
FISH Fluorescence in situ hybridization
CSF Cerebrospinal fluid
PCR Polymerase chain reaction
CBC Complete blood count
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6. Introduction
 Leukemia is characterized by hyperproliferation of
immature white blood cells
• Normally, the rate of new cell growth and old cell death are
kept in balance
• In leukemia, this balance is disturbed
1) Uncontrolled cell’s growth
2) Loss of cell’s ability to undergo apoptosis (cell death)
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7. • Normal person Leukemic patient
• Red
Blood
Cell
• White
Blood Cell Hyperproliferation of white
blood cell
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8. Type of Cell Affected
There are two main types of white blood cells:
o Lymphocytes
o Granulocytes
 Leukemia involving lymphocytes is called lymphocytic leukemia.
 Leukemia involving granulocytes is called myeloid or
myelogenous leukemia.
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10. Acute Leukemia :
 In Acute leukemia malignant transformation occurs in the
haemopoietic stem cell
 The presence of 20% of blast cells in the blood
 Less than 20% blasts cytogenetic or Molecular genetics
abnormalities are present
 Progress rapidly
 Common in younger age
 Short clinical course (weeks to months)
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11. Types of Acute leukemia
There are two types of acute leukemia
 Acute myeloid leukemia - (AML)
 Acute lymphoblastic leukemia - (ALL)
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12. Acute myeloid leukemia
 Acute myeloid leukemia (AML) is a malignant disease of the
bone marrow in which excessive production of immature
myeloblast cells.
 80% in adult
 In 30% cases have N-ras-gene mutation
 25% cases have RB1 gene
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13. Acute lymphoblastic leukemia-ALL
 Commonest form of malignancy in childhood
 Peak incidence at 4-5 years of age
 Acute onset with short history of duration
 85% are B cell , 15% are T cell
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14. Acute lymphoblastic leukemia-ALL
 10-25% cases have abnormalities of N-ras gene
 20-25 % have fusion of the tal-1 gene
 Less frequently involved tal-2, Ttg-2 , HOX-11 genes
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15. Chronic leukemia
 In chronic leukemia the leukemia cells are more mature cells, but they
are not completely normal. They generally do not fight infection as well
as normal WBCs
 Progress slowly
 Common in older age
 Longer clinical course (years)
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16. Types of chronic leukemia
There are two types of Chronic leukemia
 Chronic myeloid (or myelogenous) leukemia (CML)
 Chronic lymphocytic leukemia (CLL)
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17. Chronic myeloid leukemia (CML)
 Myeloid leukemia (myelogenous ) also known as granulocytic
leukemia is a cancer of the white blood cells.
 It is a clonal disorder of a stem cell
 Common in adults
 The pathogenesis of CML involving the fusion of the ABL-gene
on chromosome 9 and BCR-gene on chromosome 22
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18. Chronic lymphocytic leukemia (CLL)
 Chronic neoplastic disorder characterized by accumulation of
small mature –looking lymphocytes which are immunologically
immature in blood , bone marrow and lymph nodes.
 Occur in older patients (>50 year old)
 Abnormalities of p53 and bcl-1 gene
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20. Risk Factors:
 Smoking
 Genetic disorder
 Radiation
 Chemotherapy
 Chemicals
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21. Clinical feature :
 Bycytopenia :
• Hb- anemia
• Platelets
 Organ infiltration:
• Lymphadenopathy
• Splenomegaly more common with ALL than AML
• Hepatomegaly
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22. Diagnosis:
 CBC
 peripheral smear
 Bone marrow
 Cytogenetic
 FISH
 PCR
 Immunohistochemistry
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23. Treatment :
 Chemotherapy
 Radiotherapy
 Bone marrow transplant
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