In Vitro and In Silico Study on the Impact of Chlorogenic Acid in Colorectal Cancer Cells: Proliferation, Apoptosis, and Interaction with β-Catenin and LRP6

Targeting LRP6: A new strategy for cancer therapy

Targeting specific molecular drivers of tumor growth is a key approach in cancer therapy. Among these targets, the low-density lipoprotein receptor-related protein 6 (LRP6), a vital component of the Wnt signaling pathway, has emerged as an intriguing candidate. As a cell-surface receptor and vital co-receptor, LRP6 is frequently overexpressed in various cancer types, implicating its pivotal role in driving tumor progression. The pursuit of LRP6 as a target for cancer treatment has gained substantial traction, offering a promising avenue for therapeutic intervention. Here, this comprehensive review explores recent breakthroughs in our understanding of LRP6's functions and underlying molecular mechanisms, providing a profound discussion of its involvement in cancer pathogenesis and drug resistance. Importantly, we go beyond discussing LRP6's role in cancer by discussing diverse potential therapeutic approaches targeting this enigmatic protein. These approaches encompass a wide spectrum, including pharmacological agents, natural compounds, non-coding RNAs, epigenetic factors, proteins, and peptides that modulate LRP6 expression or disrupt its interactions. In addition, also discussed the challenges associated with developing LRP6 inhibitors and their advantages over Wnt inhibitors, as well as the drugs that have entered phase II clinical trials. By shedding light on these innovative strategies, we aim to underscore LRP6's significance as a valuable and multifaceted target for cancer treatment, igniting enthusiasm for further research and facilitating translation into clinical applications.

The Emerging Role of Natural Products in Cancer Treatment

The exploration of natural products as potential agents for cancer treatment has garnered significant attention in recent years. In this comprehensive review, we delve into the diverse array of natural compounds, including alkaloids, carbohydrates, flavonoids, lignans, polyketides, saponins, tannins, and terpenoids, highlighting their emerging roles in cancer therapy. These compounds, derived from various botanical sources, exhibit a wide range of mechanisms of action, targeting critical pathways involved in cancer progression such as cell proliferation, apoptosis, angiogenesis, and metastasis. Through a meticulous examination of preclinical and clinical studies, we provide insights into the therapeutic potential of these natural products across different cancer types. Furthermore, we discuss the advantages and challenges associated with their use in cancer treatment, emphasizing the need for further research to optimize their efficacy, pharmacokinetics, and delivery methods. Overall, this review underscores the importance of natural products in advancing cancer therapeutics and paves the way for future investigations into their clinical applications.

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.

Data on the cytotoxicity of chlorogenic acid in 3D cultures of HT-29 cells

Functional foods, beyond basic nutrition, offer health benefits to consumers thanks to the presence of bioactive compounds such as some phytochemicals [1,2]. Today, these foods are of particular interest in biomedical research due to their chemopreventive potential, as they have been shown to induce various biological effects on tumor cells, including the ability to inhibit cell proliferation, induce apoptosis, arrest cell cycle progression, and increase reactive oxygen species [3,4]. Multiple studies have confirmed the relationship between diet and the onset and progression of colorectal cancer (CRC), a malignant neoplasm that arises in the lining of the colon and/or rectum. Therefore, finding foods that can intervene in the carcinogenesis process is an important avenue of research [5,6]. Chlorogenic acid (CGA) is one of the most abundant phenolic compounds in coffee and is also found in fruits and vegetables. Scientific evidence suggests that CGA has chemopreventive potential on CRC cells [7], [8], [9]. For example, in previous studies conducted by our research group, green and roasted coffee extracts were characterized, and this compound was identified as the most abundant [7]. In addition, it was found to significantly decrease cell viability, reduce migration capacity, cause DNA fragmentation, and induce the production of reactive oxygen species in colorectal adenocarcinoma cells cultured in monolayer and treated with different doses of CGA. Furthermore, the mechanism underlying this biological activity has been related to CGA's ability to modulate the Wnt- /β-catenin pathway, which is implicated in the development and progression of CRC [7,10,11]. This paper presents data on the cytotoxic response of CGA treatments on HT-29 cells cultured in a 3D model. To this end, morphological changes in cell spheroids, propidium iodide and DiOC6 uptake, quantification of reactive oxygen species (ROS) production, phosphatidylserine exposure, and cell cycle progression were evaluated by flow cytometry.

New Insights of Biological Functions of Natural Polyphenols in Inflammatory Intestinal Diseases

The intestine is critically crucial for nutrient absorption and host defense against exogenous stimuli. Inflammation-related intestinal diseases, including enteritis, inflammatory bowel disease (IBD), and colorectal cancer (CRC), are heavy burdens for human beings due to their high incidence and devastating clinical symptoms. Current studies have confirmed that inflammatory responses, along with oxidative stress and dysbiosis as critical pathogenesis, are involved in most intestinal diseases. Polyphenols are secondary metabolites derived from plants, which possess convincible anti-oxidative and anti-inflammatory properties, as well as regulation of intestinal microbiome, indicating the potential applications in enterocolitis and CRC. Actually, accumulating studies based on the biological functions of polyphenols have been performed to investigate the functional roles and underlying mechanisms over the last few decades. Based on the mounting evidence of literature, the objective of this review is to outline the current research progress regarding the category, biological functions, and metabolism of polyphenols within the intestine, as well as applications for the prevention and treatment of intestinal diseases, which might provide ever-expanding new insights for the utilization of natural polyphenols.