Colorectal cancer is the cancer of colon or rectum of the large intestine. It occurs when malignant growth is formed in the lining of the large intestine.
Mostly colorectal cancer arises from colorectal polyps (benign clump of cells formed in the lining of colon or rectum). Sometimes, these polyps may be pre-cancerous and turn into cancer.
The colorectal cancer is common among both men and women and is preventable and curable if detected early. Regular colonoscopy or sigmoidoscopy can detect any abnormal growth in the lower digestive system.
Most colorectal cancers show symptoms at very late stages. Symptoms may vary depending upon whether the cancer is in right or left colon.
However, a few symptoms should be checked for, such as a change in bowel habits, blood in stool, abdominal pain, diarrhea, cramps, bloating, weakness, fatigue, weight loss, anaemia etc.
The risk of this disease is high in people above 50 years of age. The family history of colorectal cancer, obesity, alcoholism, high intake of red meat in the diet, smoking and physical inactivity is other common risk factors associated with it.
Certain medical conditions also increase the risk of colorectal cancer. These include inflammatory bowel disease (IBD) like ulcerative colitis and Crohn’s disease and type 2 diabetes.
Surgery is the most commonly employed treatment for colorectal cancer. Chemotherapy, radiotherapy and targeted therapy are also used its treatment.
These treatment methods are frequently encountered with several side-effects. The side-effects are neuropathy, increased susceptibility to infections, nausea, upset stomach, hair loss, fatigue, skin problems and much more.
The side-effects posed by the treatment options available for the colorectal cancer is increasing driving toward the need for alternative medicines which have minimum side-effects and maximum overall benefits.
Such an alternative approach can be found in the natural phytochemicals like curcumin.
What is curcumin?
Curcumin or diferuloylmethane is the polyphenolic compound present abundantly in the roots of turmeric, i.e. Curcuma longa.
It is the component of the common household spice responsible for its yellow-orange colour.
Curcumin is also the most biologically active constituent of turmeric. It has the ability to interact with various molecular pathways of a living cell and modulate them to incur therapeutic benefits.
The common properties of curcumin that provide therapeutic benefits are antioxidant, anti-inflammatory, anti-microbial, anti-cancer, immune-modulatory, etc.
These properties have useful implications in innumerable diseases, from diabetes and infections to neurodegenerative diseases and cancer.
6 Proven Benefits of Curcumin in Colon Cancer
The extraordinary biological properties of curcumin have one of the greatest benefits in cancer. It can target various aspects of the disease to inhibit the development of the disease and aid in the treatment.
1. Curcumin destroys colon cancer cells
The origin of colon cancer lies in the abnormal division of cells of the inner lining of the colorectal region, which may eventually develop in malignancy.
The survival of the cancer cells depends upon the interplay of various survival proteins and dysfunction in apoptotic pathways.
Curcumin can target the pathways involved in the survival of the cancer cells and kill those cells.
It is known to induce apoptosis or cell death in the colorectal cancer cells by increasing Bax and p53 (proteins that are involved in cell death) expressions and reducing Bcl-2 and Survivin (proteins that support cell survival) expressions through mitochondria-mediated pathways.
Curcumin also downregulates the enzyme hexokinase II (involved in cancer growth) and disrupts the metabolism in the cancer cells and thus, induces apoptosis.
Dimethoxycurcumin, a curcuminoid has been found to reduce the expression of survivin (cell survival protein) and increases the expression of E-cadherin (involved in tumour suppression) and thus, induce apoptosis in colon cancer cells.
There is also a finding that curcumin increases reactive oxygen species (ROS) production in the colorectal cancer cells that result in the disruption of the mitochondrial membrane (mitochondria are powerhouse units of the cells), finally resulting in the cell death.
Relapse is a common phenomenon in colorectal cancer cases due to the presence of cancer stem cells (CSCs) in the tumour. Curcumin can target these stem cells and induce apoptosis in them by means of regulating many pathways.
What does it mean?
It means curcumin can be an effective measure for the treatment of colorectal cancer. It kills not only the colorectal cancer cells but also the cancer stem cells, providing a solution for cancer relapse as well.
2. Curcumin inhibits proliferation and metastasis in colon cancer
Tumour proliferation is innate to cancer and metastasis (formation of secondary tumours at a distance from the primary site) is also a very common phenomenon. These processes primarily are involved in making the disease deadly.
Curcumin takes care of these as well. It can inhibit the proliferation of cancer and prevent the cancer metastasis.
It is known to target the CDK2 protein (involved in the cell cycle). The inhibition of this protein by curcumin results in the cell cycle arrest and thus, the inhibition of the colorectal cancer cell growth.
Curcumin also shows antiproliferative activity by activating the apoptotic signaling in the colon cancer cells.
Curcumin suppresses the invasion or metastasis of the colorectal cancer cells as well. It inhibits the NF-kappa B pathway, uPA activator and MMP9 (involved in cancer progression) and thus, prevents invasion of cancer.
It is also known to inhibit the expression of miR-21 gene (expressed highly in tumours) and thus, suppress the invasion and metastasis of colorectal cancer.
What does it mean?
It means curcumin administration to colorectal cancer patients can inhibit the proliferation and suppress the metastasis.
3. Curcumin reduces inflammation
Inflammation is closely linked to colorectal cancer. The inflammatory mediators are known to promote tumour growth and invasion. People with inflammatory bowel disease (IBD) are, therefore, considered to be at a greater risk of developing colorectal cancer.
Curcumin has significant anti-inflammatory action and is known to have therapeutic effects in numerous inflammatory conditions including cancer.
It targets inflammatory pathways such as NF-kappa B and STAT3 to reduce the inflammation in different types of cancers including colorectal cancer.
In a study, curcumin was found to decrease the expression of pro-inflammatory molecules such as TNF-α, IL-1β, IL-6, etc. (involved in tumour formation). The reduction in inflammation was efficacious in targeting colorectal cancer development.
In a clinical trial, curcumin administration was able to reduce the inflammatory responses in the participants and prevent the development of colorectal cancer. It was a result of the inhibition the inflammatory pathway NF-kappa B by curcumin.
What does it mean?
It means curcumin supplementation can reduce inflammation and thus can target the inflammation-mediated colorectal cancer. A regular consumption of curcumin can prevent the development of tumours in the colon.
4. Curcumin overcomes drug resistance and assists in chemotherapy
One of the major hindrances faced during the treatment of colorectal cancer is the resistance of cancer cells to the chemotherapeutic drugs.
The resistance occurs due to mutations or interference of different pathways with each other, resulting in ineffectiveness of the chemotherapy.
Curcumin is able to overcome this problem too. It can reverse the drug resistance and enhance the effectiveness of the therapy by synergistically acting with the chemotherapeutic drugs.
In a study, curcumin was found to switch the multi-drug resistance in colon cancer cells to normal and significantly inhibited the growth of the tumour.
In 5-Fluorouracil resistant colon cancer cells, curcumin treatment could sensitize the cancer cells to the drug.
Curcumin is known to have synergistic activity with the chemotherapeutic drugs like 5-Fluorouracil, oxaliplatin, gemcitabine, etc.
The combination of Curcumin with the chemotherapeutic drug, oxaliplatin, has been found to increase the effectiveness of the drug by inducing apoptosis through suppressing the expression of the survival proteins in the colorectal cancer cells.
Diclofenac (a NSAID) is also used to reduce inflammation in the colorectal cancer patients. When combined with curcumin, its efficacy increases in the treatment through upregulation of tumour suppressor proteins resulting in induction of cell cycle arrest and apoptosis.
What does it mean?
It means combining curcumin with other drugs can help conquer drug resistance in colorectal cancer. It can also enhance the effectiveness of the chemotherapy by acting in a synergistic manner with the drugs.
5. Curcumin has chemopreventive activity
Since colorectal cancer is hard to detect at early stages and its treatment becomes difficult at the later stages, it is best to take measures that can prevent the occurrence of this disease.
One of the effective and easy measures is to include curcumin in the regular diet. Curcumin has a very high chemopreventive potential and can reduce the risk of cancer.
It inhibits not only the carcinogenic (cancer development) process but also deactivates carcinogens (cancer causing agents).
Curcumin’s action on the molecular pathways that are involved in inflammation and survival of the colorectal cancer cells induces cell cycle arrest and apoptosis, protecting the body from the development of this disease.
Curcumin is also known to protect from colorectal cancer by altering DNA methylation (a process that changes the activity of DNA) in the cancer cells.
It results in changes in the gene expression of various genes in the cancer cells, ultimately leading to the cell death.
What does it mean?
It means the inclusion of curcumin in regular diet can protect the body from colorectal cancer. Curcumin prevents the development of cancer through various mechanisms and also deactivates cancer-causing substances.
6. Curcumin protects from the side effects of the chemotherapy
One of the major drawbacks of chemotherapy is the side effects of the chemotherapeutic drugs. Different drugs result in different types of toxicities such as neuropathy, kidney damage, lungs damage, heart damage, gastrointestinal damage, etc.
5- Fluorouracil is commonly employed chemotherapeutic drug in the treatment of colorectal cancer. It is known to cause gastrointestinal damage, skin problems, mucositis, etc.
Curcumin has been found to protect the normal cells of the gastrointestinal region from the damages caused by 5-Fluorouracil.
Curcumin treatment could successfully reverse the drug-induced weight loss and structural damage to the inner lining of the intestine.
Oxaliplatin is another frequently used chemotherapeutic drug in the treatment of colorectal cancer.
It is known to cause side effects such as neurotoxicity (nerve damage), ocular toxicity (eye damage), hepatotoxicity (lung damage), etc.
Curcumin has been found to protect the nerves from oxaliplatin-induced neurotoxicity through its antioxidant and anti-inflammatory mechanisms.
It also has protective action against lung damage caused by platinum-based drugs, such as cisplatin and oxaliplatin.
What does it mean?
It means taking curcumin can protect the body from the various side effects caused by the chemotherapeutic drugs used in colorectal cancer treatment. It can help in better management of the side effects and thus, improve the treatment of the patients.
Dosage of Curcumin For Colon Cancer
There is no specific dose of curcumin outlined for colon cancer. However, the dose of curcumin ranging from 2g to 8g have safe and effective results in individuals with colon cancer.
Preferably, curcumin consumption should be initiated with small doses. The dose can be raised over weeks slowly. A dose plan should be followed by the colorectal cancer patients to achieve maximum benefits. (Read Turmeric/ Curcumin Dosage for Cancer: A Scientific Plan).
Curcumin supplements are normalized 95% Curcumin with Bioperine. The combination of curcumin with piperine and natural fats boosts its bioavailability in the body. (Read How to improve the bioavailability of curcumin?)
Various curcumin formulations have been developed to overcome the bioavailability problems. These formulations include nanocrystals, liposomes, polymer-based nano-formulations, Meriva, Theracumin, etc.
There are diverse other curcumin supplements that have an improved absorption in the body. (Read 8 Popular curcumin supplement types)
Preferably, curcumin intake should be started with small doses. The dose can be enhanced gradually over weeks.
Moreover, curcumin should be consumed is after meals. Also, a gap of 3-4 hours must be maintained between curcumin intake and medicines.
Safety of turmeric in the diet is renowned. Curcumin has also been established to be safe even in high doses in most of the studies.
A few precautions are necessary to take while using curcumin. (Read Side-effects & Precautions of Curcumin)
Curcumin may cause allergies in sensitive individuals. Please conduct a patch test before applying curcumin topically.
Curcumin may cause acid reflux in the prone individuals. Therefore, it should be consumed after a meal.
Large dose of curcumin can cause gastric discomfort like diarrhea, bloating, nausea etc. Therefore, it is advisable to start curcumin with low doses, and its intake should be avoided in case any severe gastric side-effects are observed.
Curcumin interferes in drug metabolism. Therefore, 3-4 hours gap must be maintained between taking curcumin and any medication. An expert’s opinion is best to take in this matter.
Curcumin may increase the risk of bleeding owing to its blood thinning activity. Therefore, people with bleeding disorders or on blood thinning medication should refrain from curcumin. (Read Is turmeric a blood thinner?)
Curcumin intake should be discontinued at least two weeks ahead of a surgery and after that as well.
Gallstone Patients should take curcumin supplements if advised by health practitioner.(Read Is turmeric safe in gallstones?)
Curcumin supplements must be devoid of contamination. Curcumin supplements can have contaminants such as heavy metals, harmful chemicals, fillers or additives. These contaminants may be a potent disease (such as cancer, ulcers, etc.) causing agents.
Curcumin supplements are excellent when combined with bioavailability boosters. Curcumin is poorly available to the body. Therefore, it is best to integrate curcumin with the agents like Bioperine which increase its absorption in the body.
A medical expert must be consulted before using curcumin supplements, especially in cancer therapy.
Curcumin is a boon for colorectal cancer patients.
It is a natural alternative that has a very wide applicability in this disease. It provides a solution to almost all the problems associated with colorectal cancer.
Curcumin kills the cancer cells, prevents invasion of the disease and metastasis. It acts against inflammation (an important aspect of this disease) and also overcomes the issue of drug-resistance and increases drug efficacy.
Moreover, its chemopreventive activity prevents the very development of the disease and its protective action in the various normal tissues of the body saves from the side effects of the chemotherapeutic drugs.
In conclusion, the benefits of curcumin are unmatched in this disease.