Effects of a Chlorogenic Acid-Containing Herbal Medicine (LASNB) on Colon Cancer

Anticancer potential of hydroxycinnamic acids: mechanisms, bioavailability, and therapeutic applications

Hydroxycinnamic acids (HCAs) are plant compounds with anticancer potential due to their antioxidant, anti-inflammatory, apoptosis-inducing, and proliferation-inhibiting effects. This review aims to consolidate and analyze current knowledge on the anticancer effects of HCAs, exploring their mechanisms of action, bioavailability challenges, and potential therapeutic applications. A comprehensive literature search on PubMed/MedLine, Scopus, Web of Science, and Google Scholar focused on the anticancer properties, mechanisms, bioavailability, and safety profiles of HCAs. Studies have shown that HCAs, such as caffeic acid, ferulic acid, and sinapic acid, inhibit the growth of cancer cells in vitro and in vivo and sensitize cancer cells to chemotherapy and radiation therapy. These effects are mediated by mechanisms including the inhibition of cell survival pathways, modulation of gene expression, and induction of oxidative stress and DNA damage. Additionally, several studies have demonstrated that HCAs exhibit selective toxicity, with a higher propensity to induce cell death in cancerous cells compared to normal cells. However, the toxicity profile of HCAs can vary depending on the specific compound, dosage, and experimental conditions. The anticancer properties of HCAs suggest potential applications in cancer prevention and treatment. However, it is essential to distinguish between their use as dietary supplements and therapeutic agents, as the dosage and formulation suitable for dietary supplements may be insufficient for therapeutic purposes. The regulatory and practical implications of using HCAs in these different contexts require careful consideration. Further research is needed to determine appropriate dosages, formulations, long-term effects, and regulatory frameworks for HCAs as both dietary supplements and therapeutic agents.

Chlorogenic acid induces apoptosis and cell-cycle arrest in colorectal cancer cells

BACKGROUND

Apoptotic agents from natural products like phenolic compounds can be used effectively in the treatment of cancer. Chlorogenic acid (CGA) is one of the phenolic compounds in medicinal plants with anti-cancer properties. In this research, we aimed to explore the anti-cancer mode of action of CGA on colorectal cancer (CRC) cells in vitro conditions.

METHODS

HT-29 and HEK-293 cells were cultured after MTT assay for 24 h with CGA 100 µM, and without CGA. Then, flow cytometry assays and the expression of apoptosis-related genes including caspase 3 and 9, Bcl-2 and Bax, and cell cycle-related genes including P21, P53 and NF-κB at mRNA and protein levels were examined. Finally, we measured the amount of intracellular reactive oxygen species (ROS).

RESULTS

The cell viability of all two-cell lines decreased in a dose-dependent manner. Moreover, CGA induces cell cycle arrest in HT-29 cells by increasing the expression of P21 and P53. It also induces apoptosis in HT-29 cells by mitigating Bcl-2 and NF-κB expression and elevating caspase 3 and 9 expression and ROS levels.

CONCLUSIONS

Considering the cytotoxicity and cell cycle arrest and induction of apoptosis in the colon cancer cell line by CGA, it can be concluded that CGA is a suitable option for the treatment of colon cancer.

Stem Cell Models for Cancer Therapy

Metastatic progression of female breast and colon cancer represents a major cause of mortality in women. Spontaneous/acquired resistance to conventional and targeted chemo-endocrine therapy is associated with the emergence of drug-resistant tumor-initiating cancer stem cell populations. The cancer-initiating premalignant stem cells exhibit activation of select cancer cell signaling pathways and undergo epithelial-mesenchymal transition, leading to the evolution of a metastatic phenotype. The development of reliable cancer stem cell models provides valuable experimental approaches to identify novel testable therapeutic alternatives for therapy-resistant cancer. Drug-resistant stem cell models for molecular subtypes of clinical breast cancer and for genetically predisposed colon cancer are developed by selecting epithelial cells that survive in the presence of cytostatic concentrations of relevant therapeutic agents. These putative stem cells are characterized by the expression status of select cellular and molecular stem cell markers. The stem cell models are utilized as experimental approaches to examine the stem-cell-targeted growth inhibitory efficacy of naturally occurring dietary phytochemicals. The present review provides a systematic discussion on (i) conceptual and experimental aspects relevant to the chemo-endocrine therapy of breast and colon cancer, (ii) molecular/cellular aspects of cancer stem cells and (iii) potential stem-cell-targeting lead compounds as testable alternatives against the progression of therapy-resistant breast and colon cancer.

Drug-Resistant Stem Cells: Novel Approach for Colon Cancer Therapy

BACKGROUND

Next to breast cancer, advanced stage metastatic colon cancer represents a major cause for mortality in women. Germline or somatic mutations in tumor suppressor genes or in DNA mismatch repair genes represent risk factors for genetic predisposition of colon cancer that are also detectable in sporadic colon cancer. Conventional chemotherapy for colon cancer includes combination of 5-fluoro-uracil with oxaliplatin and irinotecan or targeted therapy with non-steroid anti-inflammatory drugs and selective cyclooxygenase-2 inhibitors. Major limitations of these therapeutic interventions are associated with systemic toxicity, acquired tumor resistance and the emergence of drug resistant stem cells that favor initiation, progression and metastasis of therapy-resistant disease. These limitations emphasize an unmet need to identify tumor stem cell selective testable alternatives. Drug-resistant stem cell models facilitate the identification of new testable alternatives from natural phytochemicals and herbal formulations. The goal of this review is to provide an overview relevant to the current status of conventional/targeted therapy, the role of cancer stem cells and the status of testable alternatives for therapy-resistant colon cancer. Experimental models: Hyper-proliferative and tumorigenic cell lines from genetically predisposed colonic tissues of female mice represent experimental models. Chemotherapeutic agents select drug-resistant phenotypes that exhibit upregulated expressions of cellular and molecular stem cell markers. Mechanistically distinct natural phytochemicals effectively inhibit stem cell growth and downregulate the expressions of stem cell markers.

CONCLUSIONS

The present review discusses the status of colon cancer therapy and inherent limitations, cancer stem cell biology, potential lead compounds and their advantages over chemotherapy. The present experimental approaches will facilitate the identification of pharmacological and naturally-occurring agents as lead compounds for stem cell targeted therapy of colon cancer.