ABIRA KHAN TUMOR MARKERS & CANCER TREATMENT

TUMOR MARKERS Biological substances synthesized and released by cancer cells or produced by the host in response to the presence of tumor Detected in a solid tumor, in circulating tumor cells in peripheral blood, in lymph nodes, in bone marrow, or in other body fluid (urine, stool, ascites)

APPLICATIONS OF TUMOR MARKERS Population Screening Diagnosis Establishing prognosis, staging Postoperatory evaluation ： access the radicality of the surgery Monitor treatment response Surveillance for recurrence Targets for therapeutic intervention

TUMOR ANTIGENS Presented by MHC I or MHC II molecules on the surface of tumor cells TATA (Tumor Associated Transgenic Antigen) are of 2 types Tumor Antigen 1.Shared by many tumors 2.Viral Origin 3.Nuclear protein play a major role in maintaining cancerous state TSTA (Tumor Specific Transplantation Antigen) 1.Due to alteration of tumor genes or gene expressions

COMMON TUMOR MARKERS

CANCER TREATMENT Cancers account for 20-25% of deaths in clinical practices Depends on type, stage, overall condition, goal of treatment Types: 1.Surgery 2.Chemotherapy 3.Radiation therapy 4.Hormonal therapy 5.Targeted therapy A combination of these may be used

SURGERY To diagnose, Determine stage, Treat Most common type is biopsy The cancer and some adjacent tissue are removed Localized treatment Useful for predicting likelihood of recurrence

CANCER CHEMOTHERAPY Differing from the operation and radiotherapy that emphasize on the treatment of local tissues, the chemotherapy is concerned with that of the whole body Chemotherapy is the use of drugs to inhibit or kill proliferating cancer cells, while leaving host cells unharmed, or at least recoverable May consist of a single drug or a combination of drugs Intravenous, oral or other forms Systemic treatment

CLASSIFICATION OF ANTINEOPLASTIC DRUGS On the basis of antineoplastic action on the phase of proliferation cycle, drugs are classified as Cell cycle non-specific agents (phase nonspecific agents, CCNSA) (e.g. alkylating agents) 1.Act in all proliferating phases, even the G0 2.Effects are stronger Cell cycle specific agents (phase specific agents, CCSA). (e.g. Antimetabolites, vinca alkaloids) 1.Just act on specific phases of the cell cycle 2.Effects are comparatively weaker

CLASSIFICATION OF ANTINEOPLASTIC DRUGS On the basis of source and action mechanisms, the drugs are also classified as: Alkylating agents Antimetabolites Natural products Hormones and antagonists Miscellaneous agents

ACTIONS OF ANTINEOPLASTIC DRUGS Destruction of DNA or inhibition of DNA duplication- alkylating agents, mitomycin C Inhibition of nucleic acid (DNA and RNA) synthesis- 5- fluorouracil, 6-mercaptopurine, methotrexate, cytarabine, etc Interfering with the transcription to inhibit RNA synthesis- dactinomycin, dauoruicin, and doxorubicin Inhibition of protein synthesis- vinca alkaloids, epipodophylotoxins, and paclitaxel Interfering with hormone balance- adrenal corticosteroids, estrogens, tamoxifen etc Most antineoplastic drugs act on the proliferating cycle of cell

TOXICITY OF ANTINEOPLASTIC DRUGS Short-term toxicity Common side reactions usually appear earlier and many of them occur in rapidly proliferating tissues such as marrow, gastrointestinal tract, and hair follicle. Myelosuppression, Gastrointestinal tract symptom Alopecia Long-term toxicity The long-term toxicity mainly occurs in the patients who received chemotherapy many years ago Examples: carcinogenesis, teratogenesis and sterility

COMBINATION THERAPIES In order to enhance curative effect, to decrease the toxicity and to reduce the drug resistance, combination therapies are often used in the treatment Advantages of drug combinations: 1.They provide maximal cell kill within the range of tolerated toxicity 2.They are effective against a broader range of cell cycle phases 3.They may slow or prevent the development of resistance

PRINCIPLES OF COMBINATION THERAPIES Select drugs according to the cancer phase and characteristics and identify their spectrum Combinations of antineoplastic drugs with different action mechanism Combinations of antineoplastic drugs with other therapies Select drugs according to antineoplastic range (spectrum) Use right dose

RADIATION THERAPY High energy rays to kill cells Localized treatment Not useful for metastatic forms Externally/Internally delivered

TYPES OF RADIATION THERAPY External beam radiation therapy 1.3-D conformal radiation therapy 2.Intensity modulated radiation therapy 3.Image guided radiation therapy 4.Intraoperative radiation therapy Brachytherapy Stereotactic radiosurgery

HORMONAL THERAPY Natural substances regulating physiological processes Hormone overproduction can lead to cancer Drugs blocking hormones or removal of hormonal glands Systemic treatment

TARGETED THERAPY Designed to treat cancer cells only and mininize damage to normal cells Still under development Can you suggest some ideas???