By
Shimaa Abdallah Ahmed
Clinical haematology unit
2013
Introduction
 Cell cycle
 Definition of terms
 Commonly used cytotoxic drugs
(actions ,uses , toxicity
and resistance).


1.
2.
3.
4.
5.

6.

Alkylating agents
Antimetabolites
Anti-Mitotic Agents
Antibiotics
Enzymes
L-Asparaginase
Hydroxyurea




Chemotherapy is the treatment of cancer with
one or more cytotoxic anti-neoplastic drugs
("chemotherapeutic
agents")
as
part
of
a standardized regimen.
Chemotherapy may be given with a curative intent
or it may aim to prolong life or to palliate
symptoms.




Certain chemotherapeutic agents also have a role in
the
treatment
of
other
conditions,
including
ankylosing
spondylitis,
multiple
sclerosis,
Crohn's
disease, psoriasis, psoriatic arthritis, systemic lupus
erythematosus,
rheumatoid
arthritis, and scleroderma.
conditioning regimens in SCT
◦ Cyclophosphamide ,busalfan ,melphlan








Combined modality chemotherapy is the use of drugs
with other cancer treatments, such as radiation
therapy or surgery.
Induction chemotherapy is the first line treatment of
cancer with a chemotherapeutic drug. This type of
chemotherapy is used for curative intent.
Consolidation chemotherapy is the given after
remission in order to prolong the overall disease free
time and improve overall survival. The drug that is
administered is the same as the drug that achieved
remission.
Intensification chemotherapy is identical to
consolidation chemotherapy but a different drug than
the induction chemotherapy is used.






Combination chemotherapy involves treating a
patient with a number of different drugs simultaneously.
The drugs differ in their mechanism and side effects.
The biggest advantage is minimising the chances of
resistance developing to any one agent. Also, the drugs
can often be used at lower doses, reducing toxicity.
Neoadjuvant chemotherapy is given prior to a local
treatment such as surgery, and is designed to shrink the
primary tumor. It is also given to cancers with a high risk
of micrometastatic disease.
Adjuvant chemotherapy is given after a local
treatment (radiotherapy or surgery). It can be used
when there is little evidence of cancer present, but there
is risk of recurrence.






Maintenance chemotherapy is a repeated lowdose treatment to prolong remission.
Salvage chemotherapy is potentially curative high
dose ,compination regimens,given in patient with
failed or recurrent after many curative regimens .
palliative chemotherapy is given without curative
intent, but simply to decrease tumor load and
increase life expectancy.
since these drugs act by inhibiting cell division, the
most common side effects are those that occur in
areas of the body where cell replication occurs, such
as
A.
the GI mucosa (nausea, vomiting, diarrhœa),
B. the
bone marrow (myelosuppression causing
leukopænia and other blood dyscrasias), and
C.
hair follicles (alopecia).
D.
Most antineoplastics have less effects on those cells
that are non-dividing (kidney, heart) and effects on
these organs are often the result of damage to
portions of the cell other that DNA.










Originally derived from mustard gas used in the war, They are
so named because of their ability to alkylate many
molecules, including proteins, RNA and DNA.
This causes "mistakes" in the DNA that may result in
mispairing, substitutions, or excision.
This leads to a form of programmed cell death called
apoptosis.
Alkylating agents are non-cell-cycle specific
the higher the dose, the more damage to DNA
The subtypes of alkylating agents are
 Nitrogen mustards
include mechlorethamine, cyclophosphamide, melphalan
and chlorambucil.
 Alkylsulphonate Busulfan
 Nitrosoureas
include carmustine (BCNU), lomustine (CCNU)
 Tetrazines includes dacarbazine
 others
include
Cisplatin
and
derivatives
include cisplatin,carboplatin and oxaliplatin
 Non-classical alkylating agents include procarbazine .
Two DNA bases that are cross-linked by a nitrogen
mustard. Different nitrogen mustards will have different
chemical groups (R). The nitrogen mustards most
commonly alkylate the N7 nitrogen of guanine (as shown
here) but other atoms can be alkylated


Meclorethamine
◦ Uses -- (MOPP) for Hodgkin's disease and mycosis fungoids.
◦ Toxicity -- lacrimation, local damage (irritation, sloughing,
necrosis) if extravasation occurs (sodium thiosulphate)



Cyclophosphamide
◦ Uses -- Lymphoma, chronic leukæmia, numerous carcinomas,,
breast cancer, multiple myeloma, neuroblastoma and
retinoblastoma in children.
◦ Toxicity -- pulmonary fibrosis,cardiotoxicity. Other toxicities
include a syndrome of inappropriate ADH (SIADH), ridging of
nails, and hæmorrhagic cystitis. The hæmorrhagic cystitis may
be diminished by the administration of 2-mercaptoethane
sulphonate or MESNA, which donates sulphydryl groups to
inactive the drug.


Ifosfamide
◦ Uses -- Germ cell testicular cancer, sarcomas and salvage
therapy in lymphoma( ICE )
◦ Toxicity -- is nephrotoxicity and
neurotoxicity
deathNephrotoxicity may be diminished by 2-MESNA.

(coma,

Melphalan
◦ Uses -- Multiple myeloma, breast and ovarian cancers


Chlorambucil
◦ use-- Chronic lymphocytic leukemia, non-Hodkin's
lymphoma and macroglobulinæmia
◦ Toxicity -- Relatively side effect free, Pulmonary toxicity
is rare.



Alkylsulphonate(Busulfan)
◦ Use -- Chronic granulocytic leukæmia
◦ Toxicity -- pulmonary fibrosis and
syndrome .

Addison-like


Carmustine (BCNU)
chloronitrosourea

and Lomustine (CCNU)-- a

◦ Uses -- Hodkin's and non-Hodkin lymphoma, brain tumours,
multiple myeloma (mini –BEAM), malignant melanoma,mycosis
fungoides (LOCAL)
◦ Toxicity -- Pulmonary fibrosis, Liver and Renal Failure.


Triazene (Dacarbazine)
◦ Uses -- Malignant melanoma, Hodkin's lymphoma(ABVD), soft
tissue cancers, and sarcomas
Toxicity -- GI upset, mild to moderate BMS, flu-like syndrome
◦ Mechanism of Action -- These agents are bioactivated through
substitution of chloride ions for hydroxyl groups. The active
moiety then interacts with DNA, forming both inter- and intrastrand links (especially to the DNA base guanine)
◦ Uses – salvage therapy for lymphoma(DHAP,ESHAP),Ovarian,
testicular, bladder, head, neck, and endometrial cancers
◦ Toxicity -- Ototoxicity and Neurotoxicity nephrotoxicity (this
may be attenuated by hydration and diuresis), and electrolyte
disturbances (probably mediated by the liberated chloride ions).


Carboplatin
◦ Uses –salvage therapy for lymphoma(ICE) The same as cisplatin
Toxicity -- Fewer toxicities that cisplatin.





Mechanism of Action -- Procarbazine methylates
DNA, essentially acting in a manner similar to the
alkylating agents.
Additionally, free radical
formation may contribute to the action of
procarbazine. Both of these actions will decrease
DNA, RNA, and protein synthesis.
Use -- Hodkin's lymphoma(MOPP)
Toxicity -- neurotoxicity (including behavioural
changes), and a disulfiram-like reaction.
1.

Folate Antagonists -- Methotrexate

◦ Mechanism of Action -- Methotrexate inhibits dihydrofolate
reductase
◦ Methotrexate is primarily active during the S phase of the cell
cycle
◦ The toxic effects of methotrexate may be reversed by the
administration of leucovorin, which is a fully reduced folate cofactor. Leucovorin "rescue“
◦ Uses -- Acute lymphocytic leukæmia,aggressive lymphoma
(MACOP-B) choriocarcinoma, mycosis fungoides, osteogenic
sarcoma, and breast.
◦ Toxicity -- pneumonitis. Chronic side effects (seen with
methotrexate as a immunosuppressant in rheumatoid arthritis
or psoriasis) include hepatic fibrosis and cirrhosis.


5-Fluorouracil (5-FU) and Floxuridine -- these drugs are
analogues of uridine

◦ Mechanism of Action -- Both of these agents are metabolised in
vivo to F-UTP and F-dUTP which inhibit RNA and DNA
synthesis respectively
◦ Uses --Breast, GI, ovarian, cervical, bladder, prostate, and
pancreatic cancers and hepatoma.
 Cytarabine (cytosine arabinoside) -- a cytosine analogue
◦ Mechanism of Action -- activated to the nucleotide form to
substitute for CTP, inhibiting DNA chain elongation, as previously
described.
Uses -- Acute granulocytic and lymphocytic leukæmias.
◦ Toxicity -- DLT = Neurotoxicity (especially in older adults).




purine antagonists appear to substitute for
guanine or adenosine to decrease/inhibit metabolic
reactions that are necessary to form the guanine or
adenine that will be incorporated into DNA.
6-Mercaptopurine Uses -- Leukæmias
◦ Toxicity -- jaundice (33%), and hyperuricæmia and
hyperuricosuria



Azathioprine -- this drug is a 6-MP derivative that
is used for its immunosuppressive effects. The
mechanism of action is the same as 6-MP.


Fludaribine -- an adenine analogue

◦ Mechanism of Action -- Fludaribine inhibits DNA polymerase.
◦ Uses -- Chronic lymphocytic leukæmia
◦ Toxicity --chills, fever, neurotoxicity, and pulmonary toxicity.



Cladribine -- an adenine analogue

◦ Uses -- Cladribine is the drug of choice of hairy cell leukæmia



Pentostatin

◦ Mechanism of Action -- Pentostatin inhibits adenosine
deaminase to increase intracellular levels of adenosine and
deoxyadenosine nucleotides.
◦ Uses -- hairy cell leukæmia and chronic lymphocytic leukæmia
◦ Toxicity -- neurotoxicity, nephrotoxicity. Also, , rash, and
hepatotoxicity.




Mechanism of Action -- The vinca alkaloids block
cellular mitosis by directly binding to and inhibiting
tubulin formation, specifically during metaphase.
Vinblastine
◦ Uses -- metastatic testicular cancer and lymphoma(ABVD).
◦ Toxicity -- SIADH (rare), alopecia, and sloughing/necrosis
with extravasation.



Vincristine
◦ Uses -- Hodkin's and non-Hodkin lymphoma, pediatric
leukæmias, numerous solid tumours
◦ Toxicity -- Neurotoxicity









Paclitaxel (Taxol) and Docetaxel
◦ Uses -- Ovarian and breast cancers
◦ Toxicity -- These agents may also cause bradycardia (early) and
silent ventricular tachycardia (late).
Epipodophyllotoxins -Mechanism of Action -- The epipodophyllotoxins form a ternary
complex with DNA and topoisomerase II, causing double-strand
breakage. (Late S,G2 phase)
Etoposide
◦ Uses -- Testicular, breast, and small-cell lung cancers, salvage
therapy non-hodkin lymphoma (ICE,ESHAP,mini BEAM),
leukæmia, and Kaposi's sarcoma.
Teniposide
◦ Uses -- Primarily used for refractory acute lymphocytic leukæmia in
children



Anthracycline Antibiotics
Mechanism of Action –
 DNA intercalation,
 preventing DNA and RNA synthesis, single and double stranded
breaks (via topoisomerase II).
 form free radicals (ferrous ion and oxygen are necessary catalysts
for their formation) which may directly damage DNA, RNA, or
cellular components, accounting at least in part for the cytotoxic
effects of the drugs.
◦ anthracycline antibiotics form free radicals that responsible for the
cardiotoxicity associated with these drugs, through damage to the
contractile structures of the myocardium. by the administration of
an anti-oxidant (alpha-tocopherol) or an iron chelating agent
(dexrazoxane).


Daunorubicin (daunomycin, rubidomycin)



Doxorubicin (doxomycin)
Uses -- Broader spectrum of activity, used in several
solid tumours
Idarubicin
Mitoxantrone -- these are derivatives of the
anthracycline antibiotics






◦ Uses -- Primarily used for leukæmias
◦ Toxicity -- cardiotoxicity (manifest early as arrhythmia, late as
congestive failure.

◦ Mechanism of Action -- The anti-neoplastic effects of
mitoxantrone are due to DNA intercalation. It does not exhibit
the degree of free radical formation and therefore essentially
lacks the cardiotoxic effects of others in the class.




Actinomycin D (Dactinomycin)
◦ Mechanism of Action -- Dactinomycin intercalates with DNA to
prevent DNA transcription by RNA polymerase,Dactinomycin
causes strand breaks by decreasing topoisomerase II activity.
◦ Uses -- Rhabdomyosarcoma, Wilm's tumour, Choriocarcinoma,
testicular cancer, and Kaposi's sarcoma
Bleomycin
◦ Mechanism of Action -- Bleomycin binds to DNA and generate free
radicals. CCS DRUG (G2 PHASE)
◦ Uses -- Squamous cell carcinoma, œsophageal cancer, testicular
and ovarian cancer, and both Hodgkin's(ABVD) and non-Hodgkin
lymphoma(MACOP-B).
◦ Toxicity
-Pulmonary
fibrosis,
cutaneous
toxicity
(hyperpigmentation, hyperkeratosis, erythema, ulceration).


Mitomycin
◦ acts as an alkylating agent to decrease DNA
synthesis, increase cross-linking of DNA, and to cause
single-strand breakage.
◦ Uses -- cervical, colorectal, breast, bladder, and lung
cancers.
◦ Toxicity -- Hæmolytic/uremic syndrome (due to
endothelial damage of the red cells and renal
epithelium), pulmonary fibrosis and cardiotoxicity.








Mechanism of Action -- Most normal cells can synthesis
the amino acid asparagine. However, many neoplastic
cells lack this capability ,thereby depriving the
neoplastic cell of asparagine and thus inhibiting protein
synthesis, which leads to cell death by apoptosis.
Uses -- leukæmias.
Toxicity -- Hypersensitivity, However decreases in
protein synthesis may lead to insulin deficiency and
clotting factor deficiency.
Clinical Note -- methotrexate prior to L-asparaginase
increases the cytotoxic activity and side effect


Mechanism of Action -- Hydroxyurea inhibits the
enzyme ribonucleotide reductase, thereby inhibiting
the
conversion
of
ribonucleotide
to
deoxyribonucleotides. This inhibits DNA synthesis. Its
actions are specific for the G1 to S phase of the cell cycle.



Uses -- Leukæmias, polycythemia vera (overproduction
of erythrocytes), malignant melanoma. Hydroxyurea is
also used in the treatment of sickle cell anæmia to
decrease hæmolysis. This effect is mediated by an
increase in the synthesis of hæmoglobin F (probably by
a separate mechanism, possibly increased expression of
the Hgb F gene).
Acquired drug-resistant models possess multiple drugresistance mechanisms. These mechanisms include:
(a) decreased intracellular concentration of the drug
characteristic of overexpression of drug transporters;
(b) alterations in the drug target such as point mutations or
overexpression of the target;
(c) increased detoxification of the drug such as glutathione
conjucation;
(d) changes in the repair of DNA damage induced by the drug
(e) alterations in the cell cycle checkpoint such as p27or p21;
(F) changes in the ratio of pro and antiapoptotic BCL-2 family
members
Chemotherapy in hematological diseases
Chemotherapy in hematological diseases

Chemotherapy in hematological diseases

  • 2.
    By Shimaa Abdallah Ahmed Clinicalhaematology unit 2013
  • 3.
    Introduction  Cell cycle Definition of terms  Commonly used cytotoxic drugs (actions ,uses , toxicity and resistance).  1. 2. 3. 4. 5. 6. Alkylating agents Antimetabolites Anti-Mitotic Agents Antibiotics Enzymes L-Asparaginase Hydroxyurea
  • 4.
      Chemotherapy is thetreatment of cancer with one or more cytotoxic anti-neoplastic drugs ("chemotherapeutic agents") as part of a standardized regimen. Chemotherapy may be given with a curative intent or it may aim to prolong life or to palliate symptoms.
  • 5.
      Certain chemotherapeutic agentsalso have a role in the treatment of other conditions, including ankylosing spondylitis, multiple sclerosis, Crohn's disease, psoriasis, psoriatic arthritis, systemic lupus erythematosus, rheumatoid arthritis, and scleroderma. conditioning regimens in SCT ◦ Cyclophosphamide ,busalfan ,melphlan
  • 9.
        Combined modality chemotherapyis the use of drugs with other cancer treatments, such as radiation therapy or surgery. Induction chemotherapy is the first line treatment of cancer with a chemotherapeutic drug. This type of chemotherapy is used for curative intent. Consolidation chemotherapy is the given after remission in order to prolong the overall disease free time and improve overall survival. The drug that is administered is the same as the drug that achieved remission. Intensification chemotherapy is identical to consolidation chemotherapy but a different drug than the induction chemotherapy is used.
  • 10.
       Combination chemotherapy involvestreating a patient with a number of different drugs simultaneously. The drugs differ in their mechanism and side effects. The biggest advantage is minimising the chances of resistance developing to any one agent. Also, the drugs can often be used at lower doses, reducing toxicity. Neoadjuvant chemotherapy is given prior to a local treatment such as surgery, and is designed to shrink the primary tumor. It is also given to cancers with a high risk of micrometastatic disease. Adjuvant chemotherapy is given after a local treatment (radiotherapy or surgery). It can be used when there is little evidence of cancer present, but there is risk of recurrence.
  • 11.
       Maintenance chemotherapy isa repeated lowdose treatment to prolong remission. Salvage chemotherapy is potentially curative high dose ,compination regimens,given in patient with failed or recurrent after many curative regimens . palliative chemotherapy is given without curative intent, but simply to decrease tumor load and increase life expectancy.
  • 12.
    since these drugsact by inhibiting cell division, the most common side effects are those that occur in areas of the body where cell replication occurs, such as A. the GI mucosa (nausea, vomiting, diarrhœa), B. the bone marrow (myelosuppression causing leukopænia and other blood dyscrasias), and C. hair follicles (alopecia). D. Most antineoplastics have less effects on those cells that are non-dividing (kidney, heart) and effects on these organs are often the result of damage to portions of the cell other that DNA. 
  • 13.
         Originally derived frommustard gas used in the war, They are so named because of their ability to alkylate many molecules, including proteins, RNA and DNA. This causes "mistakes" in the DNA that may result in mispairing, substitutions, or excision. This leads to a form of programmed cell death called apoptosis. Alkylating agents are non-cell-cycle specific the higher the dose, the more damage to DNA
  • 14.
    The subtypes ofalkylating agents are  Nitrogen mustards include mechlorethamine, cyclophosphamide, melphalan and chlorambucil.  Alkylsulphonate Busulfan  Nitrosoureas include carmustine (BCNU), lomustine (CCNU)  Tetrazines includes dacarbazine  others include Cisplatin and derivatives include cisplatin,carboplatin and oxaliplatin  Non-classical alkylating agents include procarbazine .
  • 15.
    Two DNA basesthat are cross-linked by a nitrogen mustard. Different nitrogen mustards will have different chemical groups (R). The nitrogen mustards most commonly alkylate the N7 nitrogen of guanine (as shown here) but other atoms can be alkylated
  • 16.
     Meclorethamine ◦ Uses --(MOPP) for Hodgkin's disease and mycosis fungoids. ◦ Toxicity -- lacrimation, local damage (irritation, sloughing, necrosis) if extravasation occurs (sodium thiosulphate)  Cyclophosphamide ◦ Uses -- Lymphoma, chronic leukæmia, numerous carcinomas,, breast cancer, multiple myeloma, neuroblastoma and retinoblastoma in children. ◦ Toxicity -- pulmonary fibrosis,cardiotoxicity. Other toxicities include a syndrome of inappropriate ADH (SIADH), ridging of nails, and hæmorrhagic cystitis. The hæmorrhagic cystitis may be diminished by the administration of 2-mercaptoethane sulphonate or MESNA, which donates sulphydryl groups to inactive the drug.
  • 17.
     Ifosfamide ◦ Uses --Germ cell testicular cancer, sarcomas and salvage therapy in lymphoma( ICE ) ◦ Toxicity -- is nephrotoxicity and neurotoxicity deathNephrotoxicity may be diminished by 2-MESNA. (coma, Melphalan ◦ Uses -- Multiple myeloma, breast and ovarian cancers  Chlorambucil ◦ use-- Chronic lymphocytic leukemia, non-Hodkin's lymphoma and macroglobulinæmia ◦ Toxicity -- Relatively side effect free, Pulmonary toxicity is rare.  Alkylsulphonate(Busulfan) ◦ Use -- Chronic granulocytic leukæmia ◦ Toxicity -- pulmonary fibrosis and syndrome . Addison-like
  • 18.
     Carmustine (BCNU) chloronitrosourea and Lomustine(CCNU)-- a ◦ Uses -- Hodkin's and non-Hodkin lymphoma, brain tumours, multiple myeloma (mini –BEAM), malignant melanoma,mycosis fungoides (LOCAL) ◦ Toxicity -- Pulmonary fibrosis, Liver and Renal Failure.  Triazene (Dacarbazine) ◦ Uses -- Malignant melanoma, Hodkin's lymphoma(ABVD), soft tissue cancers, and sarcomas Toxicity -- GI upset, mild to moderate BMS, flu-like syndrome
  • 19.
    ◦ Mechanism ofAction -- These agents are bioactivated through substitution of chloride ions for hydroxyl groups. The active moiety then interacts with DNA, forming both inter- and intrastrand links (especially to the DNA base guanine) ◦ Uses – salvage therapy for lymphoma(DHAP,ESHAP),Ovarian, testicular, bladder, head, neck, and endometrial cancers ◦ Toxicity -- Ototoxicity and Neurotoxicity nephrotoxicity (this may be attenuated by hydration and diuresis), and electrolyte disturbances (probably mediated by the liberated chloride ions).  Carboplatin ◦ Uses –salvage therapy for lymphoma(ICE) The same as cisplatin Toxicity -- Fewer toxicities that cisplatin.
  • 20.
       Mechanism of Action-- Procarbazine methylates DNA, essentially acting in a manner similar to the alkylating agents. Additionally, free radical formation may contribute to the action of procarbazine. Both of these actions will decrease DNA, RNA, and protein synthesis. Use -- Hodkin's lymphoma(MOPP) Toxicity -- neurotoxicity (including behavioural changes), and a disulfiram-like reaction.
  • 22.
    1. Folate Antagonists --Methotrexate ◦ Mechanism of Action -- Methotrexate inhibits dihydrofolate reductase ◦ Methotrexate is primarily active during the S phase of the cell cycle ◦ The toxic effects of methotrexate may be reversed by the administration of leucovorin, which is a fully reduced folate cofactor. Leucovorin "rescue“ ◦ Uses -- Acute lymphocytic leukæmia,aggressive lymphoma (MACOP-B) choriocarcinoma, mycosis fungoides, osteogenic sarcoma, and breast. ◦ Toxicity -- pneumonitis. Chronic side effects (seen with methotrexate as a immunosuppressant in rheumatoid arthritis or psoriasis) include hepatic fibrosis and cirrhosis.
  • 24.
     5-Fluorouracil (5-FU) andFloxuridine -- these drugs are analogues of uridine ◦ Mechanism of Action -- Both of these agents are metabolised in vivo to F-UTP and F-dUTP which inhibit RNA and DNA synthesis respectively ◦ Uses --Breast, GI, ovarian, cervical, bladder, prostate, and pancreatic cancers and hepatoma.  Cytarabine (cytosine arabinoside) -- a cytosine analogue ◦ Mechanism of Action -- activated to the nucleotide form to substitute for CTP, inhibiting DNA chain elongation, as previously described. Uses -- Acute granulocytic and lymphocytic leukæmias. ◦ Toxicity -- DLT = Neurotoxicity (especially in older adults).
  • 25.
      purine antagonists appearto substitute for guanine or adenosine to decrease/inhibit metabolic reactions that are necessary to form the guanine or adenine that will be incorporated into DNA. 6-Mercaptopurine Uses -- Leukæmias ◦ Toxicity -- jaundice (33%), and hyperuricæmia and hyperuricosuria  Azathioprine -- this drug is a 6-MP derivative that is used for its immunosuppressive effects. The mechanism of action is the same as 6-MP.
  • 26.
     Fludaribine -- anadenine analogue ◦ Mechanism of Action -- Fludaribine inhibits DNA polymerase. ◦ Uses -- Chronic lymphocytic leukæmia ◦ Toxicity --chills, fever, neurotoxicity, and pulmonary toxicity.  Cladribine -- an adenine analogue ◦ Uses -- Cladribine is the drug of choice of hairy cell leukæmia  Pentostatin ◦ Mechanism of Action -- Pentostatin inhibits adenosine deaminase to increase intracellular levels of adenosine and deoxyadenosine nucleotides. ◦ Uses -- hairy cell leukæmia and chronic lymphocytic leukæmia ◦ Toxicity -- neurotoxicity, nephrotoxicity. Also, , rash, and hepatotoxicity.
  • 29.
      Mechanism of Action-- The vinca alkaloids block cellular mitosis by directly binding to and inhibiting tubulin formation, specifically during metaphase. Vinblastine ◦ Uses -- metastatic testicular cancer and lymphoma(ABVD). ◦ Toxicity -- SIADH (rare), alopecia, and sloughing/necrosis with extravasation.  Vincristine ◦ Uses -- Hodkin's and non-Hodkin lymphoma, pediatric leukæmias, numerous solid tumours ◦ Toxicity -- Neurotoxicity
  • 30.
         Paclitaxel (Taxol) andDocetaxel ◦ Uses -- Ovarian and breast cancers ◦ Toxicity -- These agents may also cause bradycardia (early) and silent ventricular tachycardia (late). Epipodophyllotoxins -Mechanism of Action -- The epipodophyllotoxins form a ternary complex with DNA and topoisomerase II, causing double-strand breakage. (Late S,G2 phase) Etoposide ◦ Uses -- Testicular, breast, and small-cell lung cancers, salvage therapy non-hodkin lymphoma (ICE,ESHAP,mini BEAM), leukæmia, and Kaposi's sarcoma. Teniposide ◦ Uses -- Primarily used for refractory acute lymphocytic leukæmia in children
  • 32.
      Anthracycline Antibiotics Mechanism ofAction –  DNA intercalation,  preventing DNA and RNA synthesis, single and double stranded breaks (via topoisomerase II).  form free radicals (ferrous ion and oxygen are necessary catalysts for their formation) which may directly damage DNA, RNA, or cellular components, accounting at least in part for the cytotoxic effects of the drugs. ◦ anthracycline antibiotics form free radicals that responsible for the cardiotoxicity associated with these drugs, through damage to the contractile structures of the myocardium. by the administration of an anti-oxidant (alpha-tocopherol) or an iron chelating agent (dexrazoxane).
  • 33.
     Daunorubicin (daunomycin, rubidomycin)  Doxorubicin(doxomycin) Uses -- Broader spectrum of activity, used in several solid tumours Idarubicin Mitoxantrone -- these are derivatives of the anthracycline antibiotics    ◦ Uses -- Primarily used for leukæmias ◦ Toxicity -- cardiotoxicity (manifest early as arrhythmia, late as congestive failure. ◦ Mechanism of Action -- The anti-neoplastic effects of mitoxantrone are due to DNA intercalation. It does not exhibit the degree of free radical formation and therefore essentially lacks the cardiotoxic effects of others in the class.
  • 34.
      Actinomycin D (Dactinomycin) ◦Mechanism of Action -- Dactinomycin intercalates with DNA to prevent DNA transcription by RNA polymerase,Dactinomycin causes strand breaks by decreasing topoisomerase II activity. ◦ Uses -- Rhabdomyosarcoma, Wilm's tumour, Choriocarcinoma, testicular cancer, and Kaposi's sarcoma Bleomycin ◦ Mechanism of Action -- Bleomycin binds to DNA and generate free radicals. CCS DRUG (G2 PHASE) ◦ Uses -- Squamous cell carcinoma, œsophageal cancer, testicular and ovarian cancer, and both Hodgkin's(ABVD) and non-Hodgkin lymphoma(MACOP-B). ◦ Toxicity -Pulmonary fibrosis, cutaneous toxicity (hyperpigmentation, hyperkeratosis, erythema, ulceration).
  • 35.
     Mitomycin ◦ acts asan alkylating agent to decrease DNA synthesis, increase cross-linking of DNA, and to cause single-strand breakage. ◦ Uses -- cervical, colorectal, breast, bladder, and lung cancers. ◦ Toxicity -- Hæmolytic/uremic syndrome (due to endothelial damage of the red cells and renal epithelium), pulmonary fibrosis and cardiotoxicity.
  • 36.
        Mechanism of Action-- Most normal cells can synthesis the amino acid asparagine. However, many neoplastic cells lack this capability ,thereby depriving the neoplastic cell of asparagine and thus inhibiting protein synthesis, which leads to cell death by apoptosis. Uses -- leukæmias. Toxicity -- Hypersensitivity, However decreases in protein synthesis may lead to insulin deficiency and clotting factor deficiency. Clinical Note -- methotrexate prior to L-asparaginase increases the cytotoxic activity and side effect
  • 37.
     Mechanism of Action-- Hydroxyurea inhibits the enzyme ribonucleotide reductase, thereby inhibiting the conversion of ribonucleotide to deoxyribonucleotides. This inhibits DNA synthesis. Its actions are specific for the G1 to S phase of the cell cycle.  Uses -- Leukæmias, polycythemia vera (overproduction of erythrocytes), malignant melanoma. Hydroxyurea is also used in the treatment of sickle cell anæmia to decrease hæmolysis. This effect is mediated by an increase in the synthesis of hæmoglobin F (probably by a separate mechanism, possibly increased expression of the Hgb F gene).
  • 41.
    Acquired drug-resistant modelspossess multiple drugresistance mechanisms. These mechanisms include: (a) decreased intracellular concentration of the drug characteristic of overexpression of drug transporters; (b) alterations in the drug target such as point mutations or overexpression of the target; (c) increased detoxification of the drug such as glutathione conjucation; (d) changes in the repair of DNA damage induced by the drug (e) alterations in the cell cycle checkpoint such as p27or p21; (F) changes in the ratio of pro and antiapoptotic BCL-2 family members