This document discusses drug delivery systems for cancer treatment. It describes how drug delivery aims to selectively target drugs to cancer cells while limiting effects on healthy cells through carriers like liposomes and nanoparticles, as well as methods like active targeting using ligands. The document also explains how sustained release delivery systems work to maintain therapeutic drug levels over extended periods through encapsulated formulations. Key challenges for targeted and sustained delivery include overcoming the immune system and ensuring controlled release of drugs.

1. DRUG DELIVERY SYSTEM
IN
CANCER TREATMENT
-JENISHA CHRIS.S

2. CELL CYCLE AND PROGRAMMED CELL
DEATH
 Cells continuously divide and form daughter cells, which undergo differentiation
to perform specified functions.
 Cell cycle includes a interphase, S-phase and M-phase.
 In order to maintain a balance in cell growth ,some cells undergo (PCD)
programmed cell death.
 It eliminates unnecessary cells and worn out cells.
 Unchecked cell growth and multiplication produce a mass of cells ,a tumor.

3. NEOPLASIA
Neoplasia is the abnormal
proliferation of cells.
Proliferation of cells is due to
inactivation of tumor suppressor
genes and activation of oncogenes.
Malignant neoplasm is called
cancer.

4. CHARACTERISTICS OF CANCER CELL
 PROLIFERATION: insensitivity to antigrowth signals.
 HYPOXIA: inadequate oxygen supply due to consumption of oxygen by
proliferating tumor cells.
 METABOLISM: anaerobic glycolysis.
 pH: acidic due to lactic acid production.
 RESISTANCE TO IMMUNE RESPONSE: acidic ph reduces cytotoxic T lymphocytes
function.

5. TREATMENT FOR CANCER
OPERATIVE METHODS:
 Removal of the tumor lump or infected portion of the organs .
 Disadvantage: complete cure not possible.
RADIATION :
 Exposing the cancerous region to high dosage of x-rays. X-rays affect the DNA of
the cells.
 Disadvantage: kills both cancerous as well as normal cells.

6. STEM CELL THERAPY:
 Use of stem cells (pluripotent) to replace infected tissues and organs.
 Employed in cases of leukemia and lymphoma.
 Disadvantage: miss calculation in injection leads to unwanted growth of cells.
Side effects such as infection by microbial flora of the body and rejection in case
of donor stem cell usage may occur.
CHEMOTHERAPY:
 Injection of anticancer drugs which selectively kill cells dividing at an uncontrolled
rate.
 Disadvantage: inability to differentiate between normally dividing cells and cancer
cells.

7. ANTICANCER DRUGS
All anticancer drugs act on cancer cells and kill it by damaging the part of the
cell’s control center that makes it divide. It interrupts the chemical processes involved
in cell division.
Major types include :
alkylating agents
antimetabolites
antitumor antibiotics
mitotic inhibitors

8. WORKING OF ANTICANCER DRUGS
ALKYLATING AGENTS
mechlorethamine,
cyclophosphamide, busulfan
dacarbazine, altretamine
Damage the DNA of the cell
ANTIMETABOLITES
5-flurouracil, 6-mercaptopurine Cytarabine,
Gemcitabine Hydroxyurea, Methotrexate
S-phase of cell

9. WORKING OF ANTICANCER DRUGS
ANTITUMOR ANTIBIOTICS
Anthracyclins, actinomycin-D,
mitomycin-C, bleomycin.
Alter the DNA inside cancer cell.
MITOTIC INHIBITORS
Paclitaxel, vinblastine, ixabepilone.
M-phase of cell.

10. SIDE EFFECTS OF DRUGS
 These drugs affect all rapidly dividing cells which include those in bone marrow,
hair follicles and lining of digestive system.
 As the drugs attack the DNA of the cell, it may cause long term damage to the
host cells.
 Some drugs also cause permanent damage to heart.
 These challenges maybe over come by improving target specificity and dosage
control.

11. DRUG DELIVERY SYSTEM
Drug delivery refers to approaches, formulations, technologies, and systems for
transporting a pharmaceutical compound in the body as needed to safely achieve its
desired therapeutic effect.
Routes of drug delivery system: oral, inhalation ,absorption through skin and
intravenous injection.
Drug delivery system focusses on two main aspects:
Delivery of drug only to the target.
Sustained release of drug at controlled rate.

12. TARGETED DRUG DELIVERY
 Targeted drug delivery is a type of drug delivery system where the drug is
selectively targeted or delivered only to its site of action or absorption and to the
non-target organs, tissues or cells.
 Increase of concentration only at the target.
 Higher efficiency.
 Reduced side effects.
 Usage of desired concentration of drug.

13. CARRIERS
 Carriers are substances on which the drug is loaded and transported to the target.
 Characteristics: non-toxic, biocompatible, non-immunogenic, biodegradable, and
must avoid recognition by the host's defense mechanisms.
 Major carriers: liposomes, lipoprotein-based drug carriers, nanoparticle drug
carriers, dendrimers.

14. LIPOSOMES

15. NANOPARTICLES

16. DRUG TARGETING
Active
passive
dualphysical
Ligand
mediated

17. DRUG TARGETING
.
 ACTIVE TARGETING: carrier proteins and antibodies.
 LIGAND MEDIATED TARGETING: signal triggering molecules.
 PHYSICAL TARGETING: pH, temperature, light, electric field, ionic strength and stimuli.
 PASSIVE TARGETING: physiochemical properties.
 DUAL TARGETING: carrier act as drug.

18. SUSTAINED RELEASE OF DRUGS
 The drug delivery system that are designed to prolonged therapeutic effect by
continuously releasing medication over an extended period of time after
administration of a single dose.
 Reduced fluctuation in drug level in blood.
 Reduced dosing frequency.
 Maximum bioavailability in minimum dosage.
 Reduced hospitality time.

19. SUSTAINED FORMULATIONS
 BIOLOGICAL HALF LIFE: average
 DOSAGE: minimum
 SIDE EFFECTS: no
 SOLUBILITY: good
 STABILTY: high
 NATURE: weakly acidic
 ENCAPSULATION: waxes, shellac and zein, ethyl cellulose.
 LOCALIZATION: no

20. CHALLENGES OF DRUG DELIVERY
SYSTEMS
TARGETED DELIVERY:
 Host immune defense mechanism.
 Detection of stimulus or receptors of non target sites.
SUSTAINED DELIVERY:
 Change in formulation or release rate.
 Cannot be removed.
 Dose dumping.

21. THANK YOU