Preclinical Drug Discovery in Colorectal Cancer: A Focus on Natural Compounds

Natural compounds as regulators of miRNAs: exploring a new avenue for treating colorectal cancer

Colorectal cancer (CRC) ranks as the second leading cause of cancer-related death globally, impacting both genders equally. The increasing global mortality rates from CRC are strongly linked to contemporary dietary habits, characterized by excessive meat consumption, alcohol intake, and insufficient physical activity. Thus, there is an unprecedented need to develop less hazardous and new therapies for CRC. CRC affects a substantial global population. The main treatments for CRC include chemotherapy and surgical intervention. Nonetheless, the advancement of innovative, safer, and more effective pharmaceuticals for CRC therapy is of paramount importance due to the widespread adverse effects and the dynamic nature of drug resistance. A growing amount of research suggests that natural chemicals may effectively battle CRC and, in certain cases, serve as alternatives to chemotherapeutics. Evidence suggests that miRNAs control important cancer features, including the maintenance of proliferative signals. These features also involve evasion of growth inhibition, resistance to cell death, and immortalization of replication. Additionally, miRNAs play a role in angiogenesis, invasion, and metastasis. Numerous compounds, including those exhibiting cytotoxic and apoptogenic properties against different malignancies, such as CRC, are sourced from diverse marine and medicinal plants. These chemicals stimulate several signaling pathways originating from different phytochemical families. This article evaluates the existing understanding of the anti-CRC capabilities of several phytochemical substances. Furthermore, their impact on several signaling pathways associated with cancer is examined. This article also highlights the potential of medicinal plants as a source of promising anti-CRC chemicals through modulating miRNA expression and the role of nanoparticle-based miRNA therapeutics in enhancing CRC treatment by improving tumor targeting and minimizing off-target effects.

PD15, a steroidal saponin, induces apoptosis of HCT116 colorectal cancer cells via suppressing the Akt/GSK3β pathway

OBJECTIVES

PD15, a novel natural steroidal saponin extracted from the rhizomes of Paris delavayi Franchet, has demonstrated a strong cytotoxic effect against HepG2 and U87MG cells. However, its therapeutic effects on colorectal cancer (CRC) and the underlying molecular mechanisms remain unclear.

METHODS

MTT assay, clonogenic assay, Hoechst 33258 staining, flow cytometry, molecular docking, and western blot were used to investigate the mechanism of PD15 in HCT116 cell lines. Additionally, the anti-CRC effects of PD15 were evaluated in vivo using HCT116 xenograft models.

KEY FINDINGS

PD15 significantly inhibited cell proliferation and induced G0/G1 phase arrest in HCT116 cells. Furthermore, PD15 upregulated cleaved Caspase 3 and 9, cleaved PARP, and Bax expression levels while downregulating Bcl-2, leading to apoptosis. Further experiments revealed that PD15 downregulated the protein expression of p-Akt and p-GSK3β, with LY294002 (a PI3K/Akt inhibitor) enhancing PD15-induced apoptosis and its effects on Akt/GSK3β-associated proteins. In addition, molecular docking demonstrated that PD15 exhibited strong binding affinity with Akt and GSK3β. Critically, PD15 inhibited CRC growth in vivo without causing apparent toxicity in mice.

CONCLUSIONS

These findings indicate that PD15 could trigger apoptosis by suppressing the Akt/GSK3β signaling pathway in HCT116 cells.

Conjugates of 3,5-Bis(arylidene)-4-piperidone and Sesquiterpene Lactones Have an Antitumor Effect via Resetting the Metabolic Phenotype of Cancer Cells

In recent years, researchers have often encountered the significance of the aberrant metabolism of tumor cells in the pathogenesis of malignant neoplasms. This phenomenon, known as the Warburg effect, provides a number of advantages in the survival of neoplastic cells, and its application is considered a potential strategy in the search for antitumor agents. With the aim of developing a promising platform for designing antitumor therapeutics, we synthesized a library of conjugates of 3,5-bis(arylidene)-4-piperidone and sesquiterpene lactones. To gain insight into the determinants of the biological activity of the prepared compounds, we showed that the conjugates of 3,5-bis(arylidene)-4-piperidone and sesquiterpene lactones, which are cytotoxic agents, demonstrate selective activity toward a number of tumor cell lines with glycolysis-inhibiting ability. Moreover, the results of molecular and in silico screening allowed us to identify these compounds as potential inhibitors of the pyruvate kinase M2 oncoprotein, which is the rate-determining enzyme of glycolysis. Thus, the results of our work indicate that the synthesized conjugates of 3,5-bis(arylidene)-4-piperidone and sesquiterpene lactones can be considered a promising platform for designing selective cytotoxic agents against the glycolysis process, which opens new possibilities for researchers involved in the search for antitumor therapeutics among compounds containing piperidone platforms.

A network pharmacology integrated serum pharmacochemistry strategy for uncovering efficacy of YXC on hepatocellular carcinoma

ETHNOPHARMACOLOGICAL RELEVANCE

The YangzhengXiaoji capsule (YXC) has a wide range of applications as effective traditional Chinese medicine (TCM) preparation for hepatocellular carcinoma (HCC) in China. However, the potential bioactive components and the mechanisms are yet unclear.

AIM OF THE STUDY

The treatment mechanism of YXC on HCC using a network pharmacology integrated serum pharmacochemistry strategy to investigate associated targets and pathways.

MATERIALS AND METHODS

We utilised HPLC-Q-TOF-MS/MS technology to identify components of the serum samples from both the model group and the YXC (H) group serum, which were collected from nude mice with orthotopic liver tumours. Following this, we conducted compound-target prediction and identified the overlap between the target genes in the YXC group and the oncogenes associated with HCC. The anticancer mechanisms of YXC were investigated by creating a compound-target-pathway network using the Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway and Gene Ontology (GO) analysis. The anticancer efficacy was evaluated in vitro and in vivo. Also, potential predictive targets and pathways associated with YXC in HCC treatment were assessed by western blotting.

RESULTS

The YXC (H) serum had 47 bioactive compounds compared to other models, and identified 173 specific target genes. Using the compound-target-disease network, 141 possible target genes were identified. The KEGG pathway analysis revealed vital enrichment of pathways associated with HCC, including regulating Oncology related pathways of inflammation, immunity, apoptosis, and necrosis biological processes. YXC significantly inhibited HCC cell growth in vitro and in vivo. After YXC treatment, western blotting detected alterations in the p53/Bcl-2/Bax/Caspase-3 and PI3K/Akt pathways.

CONCLUSIONS

YXC can inhibit HCC development and advancement by a variety of components, targets and pathways, especially apoptosis-induction.

Natural Products Treat Colorectal Cancer by Regulating miRNA

Diseases are evolving as living standards continue to improve. Cancer is the main cause of death and a major public health problem that seriously threatens human life. Colorectal cancer is one of the top ten most common malignant tumors in China, ranking second after gastric cancer among gastrointestinal malignant tumors, and its incidence rate is increasing dramatically each year due to changes in the dietary habits and lifestyle of the world's population. Although conventional therapies, such as surgery, chemotherapy, and radiotherapy, have profoundly impacted the treatment of colorectal cancer (CRC), drug resistance and toxicity remain substantial challenges. Natural products, such as dietary therapeutic agents, are considered the safest alternative for treating CRC. In addition, there is substantial evidence that natural products can induce apoptosis, inhibit cell cycle arrest, and reduce the invasion and migration of colon cancer cells by targeting and regulating the expression and function of miRNAs. Here, we summarize the recent research findings on the miRNA-regulation-based antitumor mechanisms of various active ingredients in natural products, highlighting how natural products target miRNA regulation in colon cancer prevention and treatment. The application of natural drug delivery systems and predictive disease biomarkers in cancer prevention and treatment is also discussed. Such approaches will contribute to the discovery of new regulatory mechanisms associated with disease pathways and provide a new theoretical basis for developing novel colon cancer drugs and compounds and identifying new therapeutic targets.

Antioxidant and Chemopreventive Activity of Protein Hydrolysates from Raw and Germinated Flour of Legumes with Commercial Interest in Colorectal Cancer

Legumes are a highly nutritious source of plant protein, fiber, minerals and vitamins. However, they also contain several bioactive compounds with significant potential benefits for human health. The objectives of this study were to evaluate the antioxidant, antitumor and chemopreventive activity of functional extracts from legumes using raw and germinated flours of six legume species of commercial interest. The methodology carried out consisted on the development of protein hydrolysates, assessment of their antioxidant capacity and in vitro tests on T84, HCT15 and SW480 colorectal cancer (CRC) cell lines. Our results showed a high antitumor activity of protein hydrolysate from M. sativa. Likewise, when combined with 5-Fluorouracile (5-Fu), there was a synergistic effect using extract concentrations from 50 to 175 µg/mL and 5-Fu concentrations from 1.5 to 5 µM. Similarly, the induction effect on detoxifying enzymes by the extracts of M. sativa, germinated V. faba Baraca × LVzt1 and V. narbonensis, which produced a higher induction rate than the positive control sulforaphane (10 µM), should be highlighted. Therefore, incorporating these enzymes into the diet could provide nutritional effects, as well as play an effective role in cancer chemoprevention and therapy.

Antioxidant and antiproliferative potential of ethanolic extracts from Moringa oleifera, Tropaeolum tuberosum and Annona cherimola in colorrectal cancer cells

Moringa oleifera, Tropaeolum tuberosum and Annona cherimola are medicinal plants traditionally used in Ecuador. However, their therapeutic properties are not completely known. We analyzed chromatographically ethanolic extracts of the seeds of M. oleifera, A. cherimola and the tubers of T. tuberosum; all presented a high content of polyphenols. The extract of A. cherimola showed the highest antioxidant activity and M. oleifera had the highest capacity to enhance the activity of detoxifying enzymes such as glutathione S-transferase and quinone oxidoreductase. The antitumor effect of these extracts was evaluated in vitro with colorectal cancer (CRC) cell lines T84, HCT-15, SW480 and HT-29, as well as with cancer stem cells (CSCs). A. cherimola and M. oleifera extracts presented the lowest IC₅₀ in T-84 and HCT-15 (resistant) cells, respectively, as well as the highest level of inhibition of proliferation in multicellular tumor spheroids of HCT-15 cells. The inhibitory effect on CSCs is noteworthy because in vivo, these cells are often responsible for cancer recurrences and resistance to chemotherapy. Moreover, all extracts showed a synergistic activity with 5-Fu. The antiproliferative mechanism of the extracts was related to overexpression of caspases 9, 8 and 3 and increased production of reactive oxygen species. In addition, we observed cell death by autophagy in M. oleifera and T. tuberosum extracts. Therefore, these ethanolic extracts are excellent candidates for future molecular analysis of the presence of bioactive compounds and in vivo studies which could improve colon cancer therapy.