INTRODUCTION:

Cancer is an abnormal growth of cells which has ability to involve adjacent tissues and even distant organs and eventual death of the affected patient if the tumour has progressed to the stage where it cannot be treated. Cancer may be regarded as a group of diseases characterised by an abnormal growth of cells, ability to invade adjacent tissues and even distant organs and the eventual death of the affected patient if the tumour has progressed beyond that stage where it can successfully removed.⁶

· There are main types of cancer are as follows:

1) Carcinomas - A carcinoma begins in the skin or the tissues that covers the surface of internal organs and glands. E.g. prostate cancer, breast cancer, lung cancer.

2) Sarcomas – A sarcoma begins in the tissues that support and connects the body. It develops in fat, muscles, nerves, joints, blood vessels, cartilage, lymph vessel or bone.

3) Leukemias – A Leukemia is a cancer of the blood. There are four main types of leukemia lymphocytic leukemia, chronic lymphocytic leukemia, acute myeloid leukemia and chronic myeloid leukemia.

4) Lymphomas – lymphoma is cancer that begins in the lymphatic system. there are two types of lymphomas: Hodgkin Lymphoma and Non Hodgkin Lymphoma.

● HERBAL DRUGS FOR TREATMENT OF CANCER:

Cancer is a complex and serious medical condition that typically requires conventional medical treatment such as surgery, chemotherapy, radiation therapy, immunotherapy or targeted therapy. This treatment are developed and tested rigorously through clinical trials.^7,8

A) ROLES OF HERBAL MEDICINE IN CANCER:

a) Primary prevention of cancer; this is important for those who have a strong family

b) Secondary presentation; prevention of recurrence of cancer is there for the objective for this group.

c) To enhance body immune system.

d) To reduce the side effects resulting from conventional therapies such as chemotherapy or radiation therapy.

e) In advanced stage of cancer, when conventional therapy have failed, many patients have no choice but resort to alternative treatment.

f) Herbal medicine used as a combination treatment with conventional cancer treatment.

Some herbs and plants compounds have been studied for their potential anti-cancer properties, but they are not considered standalone treatment for cancer. Examples of herbs and compounds that have shown some promise in laboratories studies includes:

1) Curcumin:

2) Astragalus

3) Wheat grass

4) Green tea

5) Garlic

6) Ashwagandha

7) Cinamon

8) Zinger etc.

B) NATURAL HERBS THAT ARE USED TO TREAT CANCER:

1) Curcumin- Curcumin is a natural herb which are obtained from turmeric belonging to family Zingiberaceae. It is used in cosmetic & as well as food colour. They may prevent cancer and slow the spread of cancer. They are potent anti-inflammatory agent that prevent tumour progression.¹¹

2) Astragalus- It is a herbs belongs to fabaceae family. They also known as astralagus onobrychis. They contain astragloside, triterpeneglycosides, polysaccharides. It is used to treat all type of cancer. It is also used as immune system booster.

3) Garlic- Garlic contains scientific name allium sativum which belongs to family Liliaceae. They contains allicin, phytonutrients, minerals, vitamins. They are mainly used to treat brain and colon cancer. It is also act as antioxidant, antimicrobial and immune system booster.¹¹

4) Cinamon- cinnamon having biological source Cinnamomum zeylanicum belonging to family lauraceae. Cinamon contains cinnamaldehyde, cinnamic acid, cinnamate. They mainly used to treat cervical stomach, colon, lungs and breast cancer. It also shows activity like antidiabetic, antifungal, antispasmodic, antibacterial and anti-inflammatory.¹¹

5) Zinger- zinger is a natural herb which named as zingiber officinale which belongs to family zingiberaceae. They mainly contains gingerol, shogaol, zingerone and terpenes. They are used to treat colon, prostate, ovarian cancer. It also shows anti-inflammatory, antioxidant, antidiabetic and antitumour activity.¹¹

6) Ashwagandha- Ashwagandha is derived from the root of withania somnifera which belongs to family Solanaceae. They contains withanolide A, B and D, cortisol, anaferine, withanoside V. Ashwagandha slows down growth of cancer cells. And also works as anti-inflammatory, antioxidant, antiulcer etc.¹¹

7) Green tea- green tea derived from camellia sinensis which belongs to family theaceae. They contains caffeine, catechin, gallic acid, theanine, zanthine, flavones etc. They are mainly used in treatment of colon, breast, prostate, and colorectal cancer. They also shows activity likes antioxidant, antibacterial and antidiabetics.

● COVENTIONAL TECHNIQUE USED TO TREAT CANCER:

The era of cancer chemotherapy began in the 1940s with the first use of nitrogen mustards and antifolate drugs. The practice of cancer medicine has changed dramatically allowing treatments for many previously fatal cancers. Furthermore, the adjuvant chemotherapy and hormonal therapy can extend life and prevent disease recurrence following surgical resection of different types of malignancies.

Conventional therapies. Surgery, radiation therapy, and chemotherapy alone or in combination are the most-common methods used to treat cancer. Specific treatment varies, depending on the kind of cancer, the extent of the disease, its rate of progression, the condition of the patient, and the response to therapy.

Homeopathy is not considered a conventional cancer treatment. While some people may seek complementary therapies like homeopathy for symptom management or emotional support during cancer treatment, it's essential to consult with medical professionals and follow evidence-based conventional treatments to effectively manage and treat cancer. Homeopathic remedies have not been scientifically proven to cure or treat cancer.^3,4,5

A) SURGERY:

a) Surgical removal of tumours or affected tissues is often the first step in treating cancer, if feasible. It is used for both diagnosis and therapy.

b) To obtain a sample for diagnosis surgery is usually required.

c) The removal of a suspected neoplasm or a portion of it for diagnostic purposes is termed "biopsy".

d) Surgical removal of cancer is the oldest and most classical method of treatment.

e) Curative surgery is performed on a primary neoplastic lesion, whether it is benign or malignant.

f) If metastatic lesion are present, surgery may be carried out to remove the tumours in order to reduce the amount of cancer in body, this if surgery is followed by other modification (radiotherapy and chemotherapy).

g) It is also carried out in order to remove the bulks of tumours that may obstruct or press on vital organs and passages.

B) RADIATION THERAPY:

a) High-energy radiation is used to target and destroy cancer cells or shrink tumours.

b) Radiation therapy works by damaging the DNA within cancer cells and destroying their ability to reproduce.

c) When the damaged cancer cells are destroyed by radiation, the body naturally eliminates them.

d) Normal cells can be affected by radiation, but they are able to repair themselves.

e) Sometimes radiation therapy is the only treatment a patient needs.

f) Other times, it is combined with other treatments, like surgery and chemotherapy.

C) CHEMOTHERAPY:

a) Drugs are administered orally or through intravenous infusion to kill or inhibit the growth of cancer cells throughout the body.

b) Once metastasis occurs, surgical and most probably radiation therapy are not curative.

c) Although complete cure is difficult in this stage, chemotherapy, is used for increasing the useful life-time of many patients.

• There are some cancers in advanced stages that respond well to chemotherapy

- eg, acute lymphocytic leukemia, Hodgkin's disease (a lymphoma), Burkitt's lymphoma, Ewing's sarcoma of bone, and Wilm's tumer of the kidney.

d) All these tumours are characterized by rapid growth.

e) Successive chemotherapy is related to the growth fraction of the tumour, that is, the percentage of cells undergoing cell division at any one time. Rapidly growing cancers have large growth fractions; therefore, the drugs affect greater proportion of the cell population.

f) The search for and development of new drugs is very difficult and takes a long time.

· A drug goes through several stages such as:

1. Selection of the compound

2. Screening its effectiveness in animals

3. Study how the body handles it, and

4. Finally trials on patients.

D) GENE THERAPY:

a) Gene therapy is the introduction of genes into existing cells to prevent or cure a wide range of diseases.

b) It is a technique for correcting defective genes responsible for disease development.

c) The first approved gene therapy experiment occurred on September 14, 1990 in US, when Ashanti DeSilva was treated for ADA-SCID.(9)

· TYPES OF GENE THERAPY:

1) SOMATIC GENE THERAPY – Therapeutic genes transferred into the somatic cells. Eg. Introduction of genes into bone marrow cells, blood cells, skin cells etc.

2) GERM LINE GENE THERAPY- Therapeutic genes transferred into the germ cells. Eg. Genes introduced into - eggs and sperms. It is heritable and passed on to later generations. For safety, ethical and technical reasons, it is not being attempted at present.

3) IN VIVO GENE THERAPY- • Direct delivery of therapeutic gene into target cell into patients body. Carried out by viral or non viral vector systems. It can be the only possible option in patients where individual cells cannot be cultured in vitro in sufficient numbers (e.g. brain cells). In vivo gene transfer is necessary when cultured cells cannot be re-implanted in patients effectively.

4) EX VIVO GENE THERAPY:

Isolate cells with genetic defect from a patient

Grow the cells in culture

Introduce the therapeutic genes.

Select genetically corrected cells and grow.

Transplant the modified cells to the patient.

E) TAREGETED DRUG THERAPY:

a. Drugs designed to specifically target the molecular changes in cancer cells are used to block their growth.

b. Identification and development of a therapy that promote cancer cell growth or survival.

c. Most targeted therapies are Small molecules and Monoclonal antibodies.

d. Small molecules are developed for targets that are located inside the cell.

e. Monoclonal antibodies are developed by injecting animals with purified target protiens.

· TYPES OF TARGET AGENTS:

1. Monoclonal antibodies

2. Small molecules inhibitors

3. Ablation cancer therapy

4. Thermal ablation

5. Cryoablation

6. RFA Therapy

G) STEM CELL THERAPY:

Stem cells are undifferentiated cells present in the bone mar row (BM) with an ability to differentiate into any type of Body cell. Stem cell therapeutic strategy is also one of the treatment options for cancer which are considered to be safe and effective Application of stem cell is yet in the experimental clinical trial; for example, their use in the regeneration of other damaged tissue is being explored. Mesenchymal stem cells (MSCs) are currently being used in trials that are delivered from the BM, fat tissues, and connective tissues

· TYPES OF STEM CELL THERAPY-

a) Pluripotent stem cells

b) Adult stem cells

c) Cancer stem cells

H) NATURAL ANTIOXIDANT:

The anatomy undergoes many exogenous insults, such as ultraviolet (UV) rays, pollution, and tobacco smoke, that end in the assembly of reactive species. Oxidative stress and radical oxygen species can significantly change the regulation of transcription factors by damaging the DNA and other bio-macromolecule.

● Antimetabolites:

Antimetabolites are chemotherapy drugs used to treat cancer. The antimetabolites can be divided according with the structure and function as folic acid analogs, purine analogs, pyrimidine analogs and cytidine analogs. These agents are natural metabolites which are essential for normal biochemical reactions in cells. The mechanism of action of antimetabolites includes: competition for binding sites of enzymes that participates in essential biosynthetics processes and incorporation into nucleic acids, which inhibits their normal functions figuring the apoptosis process.^1,2

The various types of antimetabolites are as follows –

1) Folic acid analogs

2) Purines analogs

3) Pyrimidine analogs etc.

● MODERN TECHNIQUES TO TREAT CANCER:

Modern techniques that are most advanced techniques than conventional method. Modern techniques are used to take immediate action on cancer cell. Modern techniques are have been significant advancements in cancer treatment techniques.⁶

· Some modern techniques to treat cancer:

1) Nanomedicine - Nanomedicine is a field that involves using nanotechnology for medical purposes. It explores the design and application of tiny particles and devices at the nanoscale (typically less than 100 nanometers) to diagnose, treat, and prevent diseases. Nanomedicine holds great potential for targeted drug delivery, imaging, and improving the precision of medical treatments, among other applications

2) Modern immunotherapy- Modern immunotherapy refers to a cutting-edge approach in the field of medicine that harnesses the body's immune system to combat diseases, particularly cancer.

· There are several types of modern immunotherapies:

A) Check point inhibitors – Checkpoint inhibitors are the type of immunotherapy. They are a treatment for cancers such as melanoma skin cancer and lung cancer. These drugs blocks different checkpoint proteins. E.g. CTLA-4 Inhibitors, PD-1 Inhibitors and PD-L1 Inhibitors.

· WORKING (mechanism of action) OF CHECKPOINT INHIBITORS:

-Anti – PD-1/ PD-L1 Response

Block binding of PD-1 to PD-L1

Allow T-Cell Activation

Increase T-cell Cytotoxic function

Tumour apoptosis (Death of tumour cell)⁶

CAR-T cell therapy:

CAR-T Cell stands for Chimeric Antigen Receptor T Cells. It is the new and modern techniques of immunotherapy and it is used to treat blood cancer. In these process patient use his own immune system against cancer.

WORKING OF CAR-T CELL THERAPY:

Doctors collects blood from patient to obtain T-cells

From obtained blood T-Cells are separated and removed

Remaining blood is given back to the patient

T-Cells contains Special receptors called Chimeric Antigen Receptors (CAR)

Millions of CAR-T cells are grown

Chemotherapy is given before CAR-T Cell therapy

New CAR-T Cells introduced into bloodstream⁶

Monoclonal Antibodies:

An antibody produced by a single clone of cells. Monoclonal antibody is therefore a single pure type of antibody. It is a protein used by the immune system to identify and neutralize foreign objects like bacteria and viruses.

● MECHANISM ACTION OF MONOCLONAL ANTIBODIES:

Monoclonal antibody binds to the proteins on the cancer cell and then monoclonal antibody blocked the protein. That’s the result inhibit protein synthesis and kill the cancer cell.

● ADVANTAGES OF MONOCLONAL ANTIBODIES:

1) With the use of monoclonal antibody reduces use of mice in antibody production.

2) Monoclonal antibody is the method of large scale production.

3) Decrease the need of laboratory personnel.

LIQUID BIOPSIES:

Liquid biopsies is a blood test that detect cancer cell or DNA that are circulating in the blood.

· ADVANTAGES:

1) Repeatable

2) Liquid biopsies is done by monitoring the patient.

3) It is used in detection of Anaplastic Lymphoma Kinase mutations.

4) Gene amplification assessment.

5) Non-invasive.⁶

GENE EDITING:

Entry of new genes into cancerous cells and slow the growth of cancer. CRISPR technology offers potential for modifying cancer genes. This treatment is very flexible and avoid range of genes.

These techniques represent a glimpse into the diverse and evolving landscape of cancer treatment. Always consult with healthcare professionals for the latest options and personalized recommendations.

CLINICAL TRIALS:

Clinical trials play a vital role in advancing cancer care by identifying new therapies and improving existing ones. Patients with cancer can participate in these trials, often through their oncologist or a specialized cancer center.¹⁰

· There are four phases of clinical trial in treatment of cancer:

Phase I: These trials assess the safety and dosage of a new treatment in a small group of patients to determine the maximum tolerated dose.	Phase II: These trials involve a larger group of patients and assess the treatment's effectiveness and side effects.
Phase III: These are large-scale trials that compare the new treatment to the current standard of care to determine which is more effective.	Phase IV: After a treatment is approved, these trials monitor its long-term safety and effectiveness in a larger patient population.

CONCLUSION:

6) We conclude that with the herbal medicine has been explored as a potential complementary approach in cancer treatment, it is crucial to emphasize that it should not replace conventional cancer therapies such as chemotherapy, radiation, or surgery.

7) We conclude that with the conventional methods to treat cancer, including surgery, chemotherapy, radiation therapy, and targeted therapies, have been crucial in managing and often curing various forms of cancer.

8) We conclude that with the modern techniques to treat cancer have made significant strides in recent years, offering patients more effectives in cancer treatment or complex diseases. Considering not only patients recovery but also caring for there well being during therapy.

REFERENCE:

1. JJ Gilman A and Phillips PS The Biological Actions and Therapeutic Applications of the B-Chloroethyl Amines and Sulfides. Scimce. 1946: 103(2675) 409-43

2. Hickell CM. Canor Treatment. Philadelphia Sminden 1990.

3. Sung H, Ferlay J, Siegel RL, et al. Global cancer statistics 2020: GLOBOCAN estimates of incidence and mortality worldwide for 36 cancers in 185 countries.

4. Ganesh K and Massagué J. Targeting metastatic cancer. Nat Med. 2021; 27: 34–44.

5. Merriel SWD, Ingle SM, May MT, et al. Retrospective cohort study evaluating clinical, biochemical and pharmacological prognostic factors for prostate cancer progression using primary care data. BMJ Open. 2021; 11: e044420.

6. www.google.com

7. Vorobiof DA, Abratt R. The cancer burden in Africa. South African Medicines Journal. 2007; 97: 937-9

8. Kuete V, Efferth T, pharmacogenomics of Cameroonian traditional herbal medicine for cancer therapy. Journal of Ethnopharmacology. 2011; 137:752-66.

9. Damaris Benny Daniel I Msc Zoology, slideshare, google.com

10. Research Journals: Look for reputable medical journals like "Cancer Research," "Nature Reviews Cancer," "Journal of Clinical Oncology," or "The Lancet Oncology."

11. Books of pharmacognosy (Nirali Prakashan) S.B.Gokhale, A.U.Tatiya, C.K.Kokate, M.G.Kalaskar.

Received on 12.10.2023 Modified on 13.04.2024

Asian J. Pharm. Res. 2024; 14(3):303-308.

DOI: 10.52711/2231-5691.2024.00047