Colorectal Cancer Prevention and Treatment

Colorectal cancer (CRC) ranks as the third most common cancer globally, claiming over 690,000 lives annually. Mortality rates in developed nations like Canada, Australia, the United States, and Europe exceed those in developing regions such as Africa and Asia.

CRC typically arises from genetic mutations affecting tumor suppressor genes, oncogenes, and DNA repair mechanisms. Around 70% of cases develop sporadically from adenoma to carcinoma, while 5% are hereditary, including Lynch syndrome and familial adenomatous polyposis. Lifestyle factors like sedentary habits, obesity, diets low in fiber and high in red meat, smoking, and alcohol abuse, along with environmental influences and gut dysbiosis, significantly contribute to CRC risk. Family history and inflammatory bowel diseases like Crohn's and ulcerative colitis further elevate susceptibility.

Key Risk Factors for Colorectal Cancer

Ø  High consumption of red meat and low fiber intake.

Ø  Sedentary lifestyles.

Ø  Unique dietary habits like pickled and dried foods, excessive chili consumption, and eating food at high temperatures.

Ø  Westernisation of diet, with a shift from traditional foods rich in complex carbohydrates to simple carbohydrates, leading to increased obesity risk.

Ø  Prevalent tobacco use in various forms, including cigarette smoking, hookah, and snuff.

Current treatment

Early-stage colorectal cancer (CRC) can be detected using methods like fecal occult blood tests, barium enema X-rays, sigmoidoscopy, and colonoscopy (the gold standard). Biomarkers such as DNA, RNA, and proteins help identify mutations and classify tumor stages, aiding in predicting disease progression and therapy. Next-generation sequencing (NGS) is also being used for CRC detection, including DNA sequencing via the ColoSeq™ assay, miRNA sequencing, and gut microbiota analysis.

Treatment typically involves tumor resection, with chemotherapy regimens like FOLFIRI and FOLFOX, sometimes combined with other drugs, depending on the CRC stage and patient condition. However, about 50% of CRC patients experience recurrence, indicating current treatments' limitations. High drug resistance, affordability, and availability issues, especially in developing regions, complicate CRC treatment, highlighting the need for improved and accessible therapies. Additionally, existing cytotoxic drugs are often linked to adverse effects.

Phytochemicals

As the phrase says, 'Everything the plants have that you want,' nature offers a vast array of bioactive compounds with remarkable health benefits. Phytochemicals, found in fruits, vegetables, grains, herbs, and spices, are non-nutritive plant compounds known for their health-promoting and disease-preventive properties. Epidemiological and clinical research shows that consuming fruits and vegetables can significantly reduce the risk of various tumors, including colorectal cancer (CRC). With 70% to 90% of CRC cases linked to diet, optimizing dietary habits can prevent most occurrences.

Various research studies highlight a strong correlation between phytochemicals and CRC prevention. Scientists are focusing on discovering non-toxic phytochemicals that could be used in combination therapies to enhance the effectiveness of chemotherapy. These compounds are being evaluated for their ability to target specific molecular pathways involved in cancer progression, with promising results seen in both preclinical and clinical studies.

Promising Phytochemicals for Colon Cancer Treatment

Several phytochemicals have shown promising effects in treating colon cancer. Here are some of the most effective ones and their sources:

Curcumin: Curcumin is a polyphenol compound derived from the spice turmeric (Curcuma longa). It exhibits potent anti-inflammatory, antioxidant, and anti-cancer properties. Curcumin has been found to inhibit the growth of colon cancer cells, induce apoptosis, and modulate key signaling pathways involved in tumor progression.

Resveratrol: Resveratrol is a stilbene compound found in grapes, berries, and peanuts. It has been shown to suppress colon cancer cell proliferation, induce cell cycle arrest, and promote apoptosis. Resveratrol metabolites can also inhibit the progression of human metastatic colon cancer cells and enhance the effects of chemotherapeutic drugs.

Sulforaphane: Sulforaphane is an isothiocyanate compound derived from cruciferous vegetables like broccoli and cabbage. It has been found to inhibit colon cancer cell growth, induce apoptosis, and modulate epigenetic changes associated with cancer. Sulforaphane-rich broccoli sprout extracts have been evaluated in clinical trials for their potential in prostate cancer prevention.

Quercetin: Quercetin is a flavonoid compound found in various fruits and vegetables, such as onions, apples, and berries. It has been shown to suppress colon cancer cell growth by targeting the Wnt/β-catenin signaling pathway. Quercetin also exhibits antioxidant and anti-inflammatory properties that may contribute to its anti-cancer effects.

Ellagic acid: Ellagic acid is a polyphenol compound found in pomegranates, raspberries, and blackberries. It has been found to inhibit colon cancer cell proliferation, induce apoptosis, and modulate the expression of genes involved in cell cycle regulation and apoptosis.

Accessible Health Benefits for Everyday Life

These phytochemicals are readily available in various fruits, vegetables, and spices that are commonly consumed in our daily diet. Incorporating these foods into a balanced diet can provide a natural source of anti-cancer compounds and may contribute to the prevention and management of colon cancer.

Moreover, these phytochemicals are generally well-tolerated and have a low risk of side effects compared to conventional cancer treatments. By understanding the sources and potential benefits of these phytochemicals, individuals can make informed choices about their dietary habits and incorporate more plant-based foods into their daily lives to support overall health and potentially reduce the risk of colon cancer.

Bottomline

Phytochemicals present in plant-based foods offer a promising avenue for cancer prevention and treatment, particularly for colorectal cancer (CRC). These bioactive compounds, which include polyphenols, flavonoids, and isothiocyanates, have demonstrated significant anti-cancer properties through various mechanisms. The consumption of a diet rich in fruits, vegetables, whole grains, and legumes not only enhances the intake of these beneficial phytochemicals but also contributes to overall health and well-being. Given the rising incidence of CRC and the limitations of conventional therapies, incorporating phytochemicals into daily diets represents a proactive and accessible strategy for individuals seeking to reduce their cancer risk and support their health. Emphasizing a plant-based diet can empower individuals to take charge of their health while potentially mitigating the burden of cancer in society.

Author is a cancer researcher and peer reviewer for the Journal of Ethnopharmacology, Elsevier. Currently, engaged in a collaborative project focused on colorectal cancer (CRC) prevention and treatment, conducted at Lovely Professional University and the University of Kashmir