Plant Medicines Used for Cancer
The mechanisms of action of plant-based medicines for cancer therapy and chemotherapy is quite similar. The ultimate aim of any chemotherapy is to destroy the cancer cells, either by direct killing or apoptosis, self programmed cell death of the abnormal cells.
There are few mechanisms that are taking place to achieve that:
• Impairing the cell division (mitosis) by binding to the microtubules of a cell structure essential for multiplication. ( eg:Vinca Alkaloids)
• Interfering the DNA synthesis of the cancer cells. _(eg:_Topoisomerase Inhibitors)
• Inhibiting the essential enzyme required for cell growth.
• Increasing the immune response towards the abnormal cells (antigen).
Drugs Made from Plant Extracts Used for Cancer Cures
Plant alkaloid chemotherapy originated from plants and is cell cycle specific. There are four categories of drugs made from plant extracts used for cancer cures.
Vinca Alkaloids: Derived from Madagascar periwinkle (Catharanthus roseus). Indications are Hodgkin’s and Non-Hodgkin’s Lymphoma (Oncovin/Vincristine, Vinblastine), Non Small Cell Lung Cancer, Metastatic Breast Cancer (Vinorelbine), Leukemia, Lymphoma, Melanoma, Breast Cancer (Vindesine).
Topoisomerase Inhibitors: Originated from the roots of May Apple plants, this agent acts by inhibiting the enzyme required for DNA transcription, replication and function to prevent DNA coiling (twisting). Amsacrine, etoposide and teniposide are some of the examples.
Taxanes: Paclitaxel, a common taxane used was first discovered in 1971 and was used in clinical in 1993. It is widely used in many cancers like breast, ovaries, lung, gastrointestinal, head and neck.
Epipodophyllotoxins: Naturally occurring in the roots of the American May Apple Plant (Podophyllum peltatum). Etoposide and Teniposide are commonly used derivatives which are effective in breaking strands of DNA.
When to Alert the Medical Oncology Team
Cancer treatment is given in cycles for different cancers. Much chemotherapy are done as day care procedure, no admission is required. Patients are allowed to spend more time at home in the presence of supportive family.
Thus, it is of paramount importance that the caretakers and patients know when to seek medical attention in between the chemo cycle:
• Fever with Chills (> 101° F / 38.3° C ) - URGENT!!
• Respiratory Problems: Usual coughing, sore throat, shortness of breath.
• Gastrointestinal Problems: Nausea, vomiting that leads to inability to take orally OR passing loose stool (diarrhea) for more than 24 hours OR no bowel movement (constipation) for more than 48 hours.
• Pain, burning sensation while passing urine.
• Unusual pain that is not relieved by current medicines.
• Unusual bruising or bleeding.
• Any new or unusual symptoms that are worrying.
Precautions in the Home After Chemotherapy Treatment
In view of the toxic nature of chemotherapy, special precaution must be taken to protect the patient and caregivers in the home. Within 48 hours after the treatment, the chemo medicine would be excreted from the body in the form of urine, stool, vomit and blood.
General precaution should be practiced for two to three days upon the treatment:
• Hazardous Waste Container: It must be marked “Hazardous Waste”, placed out of reach of children. All the used gloves, dressings, items containing body fluids are to be thrown there.
• Laundry: Handle laundry with gloves. Discard the gloves in the hazardous waste containers.
• Maintain Good Hygiene: Frequent hand washing with soap and water after contact with body fluid containing items.
• Skin Care: Seek medical attention if the skin develops irritation towards chemotherapy.
• Toilet Usage: Flush the toilet twice upon usage. Do wear gloves if handling commode, bedpan, urinal or a basin for vomiting.
• Sexual Activity: Avoidance for at least two days after treatment. Contraceptive methods should be discussed with the doctor since pregnancy is not advisable during the chemotherapy sessions.
More Helpful Resources for Cancer Patients
1. Principles of Oncologic Pharmacotherapy by Chris H. Takimoto, MD, PhD, and Emiliano Calvo, MD, PhD.
2. Alkaloids Cancer Treatment by Christy Brogan
3. Chemotherapy Precautions During and After Treatment by The Cleveland Clinic Foundation.
4. Mechanism of Inhibition of Cell Proliferation by Vinca Alkaloids by Mary Ann Jordan, Douglas T, and Leslie W