Oxyresveratrol inhibits human colon cancer cell migration through regulating epithelial-mesenchymal transition and microRNA

Resveratrol as sensitizer in colorectal cancer plasticity

Despite tremendous medical treatment successes, colorectal cancer (CRC) remains a leading cause of cancer deaths worldwide. Chemotherapy as monotherapy can lead to significant side effects and chemoresistance that can be linked to several resistance-activating biological processes, including an increase in inflammation, cellular plasticity, multidrug resistance (MDR), inhibition of the sentinel gene p53, and apoptosis. As a consequence, tumor cells can escape the effectiveness of chemotherapeutic agents. This underscores the need for cross-target therapeutic approaches that are not only pharmacologically safe but also modulate multiple potent signaling pathways and sensitize cancer cells to overcome resistance to standard drugs. In recent years, scientists have been searching for natural compounds that can be used as chemosensitizers in addition to conventional medications for the synergistic treatment of CRC. Resveratrol, a natural polyphenolic phytoalexin found in various fruits and vegetables such as peanuts, berries, and red grapes, is one of the most effective natural chemopreventive agents. Abundant in vitro and in vivo studies have shown that resveratrol, in interaction with standard drugs, is an effective chemosensitizer for CRC cells to chemotherapeutic agents and thus prevents drug resistance by modulating multiple pathways, including transcription factors, epithelial-to-mesenchymal transition-plasticity, proliferation, metastasis, angiogenesis, cell cycle, and apoptosis. The ability of resveratrol to modify multiple subcellular pathways that may suppress cancer cell plasticity and reversal of chemoresistance are critical parameters for understanding its anti-cancer effects. In this review, we focus on the chemosensitizing properties of resveratrol in CRC and, thus, its potential importance as an additive to ongoing treatments.

Anti-Cancer Potential of Phytochemicals: The Regulation of the Epithelial-Mesenchymal Transition

A biological process called epithelial-mesenchymal transition (EMT) allows epithelial cells to change into mesenchymal cells and acquire some cancer stem cell properties. EMT contributes significantly to the metastasis, invasion, and development of treatment resistance in cancer cells. Current research has demonstrated that phytochemicals are emerging as a potential source of safe and efficient anti-cancer medications. Phytochemicals could disrupt signaling pathways related to malignant cell metastasis and drug resistance by suppressing or reversing the EMT process. In this review, we briefly describe the pathophysiological properties and the molecular mechanisms of EMT in the progression of cancers, then summarize phytochemicals with diverse structures that could block the EMT process in different types of cancer. Hopefully, these will provide some guidance for future research on phytochemicals targeting EMT.

Inhibition of Ribosomal RNA Processing 15 Homolog (RRP15) Suppressed Tumor Growth, Invasion and Epithelial to Mesenchymal Transition (EMT) of Colon Cancer

Although ribosomal RNA processing 15 Homolog (RRP15) has been implicated in the occurrence of various cancers and is considered a potential target for cancer treatment, its significance in colon cancer (CC) is unclear. Thus, this present study aims to determine RRP15 expression and biological function in CC. The results demonstrated a strong expression of RRP15 in CC compared to normal colon specimens, which was correlated with poorer overall survival (OS) and disease-free survival (DFS) of the patients. Among the nine investigated CC cell lines, RRP15 demonstrated the highest and lowest expression in HCT15 and HCT116 cells, respectively. In vitro assays demonstrated that the knockdown of RRP15 inhibited the growth, colony-forming ability and invasive ability of the CC cells whereas its overexpression enhanced the above oncogenic function. Moreover, subcutaneous tumors in nude mice showed that RRP15 knockdown inhibited the CC growth while its overexpression enhanced their growth. Additionally, the knockdown of RRP15 inhibited the epithelial-mesenchymal transition (EMT), whereas overexpression of RRP15 promoted the EMT process in CC. Collectively, inhibition of RRP15 suppressed tumor growth, invasion and EMT of CC, and might be considered a promising therapeutic target for treating CC.

Larotrectinib induces autophagic cell death through AMPK/mTOR signalling in colon cancer

Larotrectinib (Lar) is a highly selective and potent small-molecule inhibitor used in patients with tropomyosin receptor kinase (TRK) fusion-positive cancers, including colon cancer. However, the underlying molecular mechanisms specifically in patients with colon cancer have not yet been explored. Our data showed that Lar significantly suppressed proliferation and migration of colon cancer cells. In addition, Lar suppressed the epithelial-mesenchymal transition (EMT) process, as evidenced by elevation in E-cadherin (E-cad), and downregulation of vimentin and matrix metalloproteinase (MMP) 2/9 expression. Furthermore, Lar was found to activate autophagic flux, in which Lar increased the ratio between LC3II/LC3I and decreased the expression of p62 in colon cancer cells. More importantly, Lar also increased AMPK phosphorylation and suppressed mTOR phosphorylation in colon cancer cells. However, when we silenced AMPK in colon cancer cells, Lar-induced accumulation of autolysomes as well as Lar-induced suppression of the EMT process were significantly diminished. An in vivo assay also confirmed that tumour volume and weight decreased in Lar-treated mice than in control mice. Taken together, this study suggests that Lar significantly suppresses colon cancer proliferation and migration by activating AMPK/mTOR-mediated autophagic cell death.

Overcoming therapeutic resistance to platinum-based drugs by targeting Epithelial–Mesenchymal transition

Platinum-based drugs (PBDs), including cisplatin, carboplatin, and oxaliplatin, have been widely used in clinical practice as mainstay treatments for various types of cancer. Although there is firm evidence of notable achievements with PBDs in the management of cancers, the acquisition of resistance to these agents is still a major challenge to efforts at cure. The introduction of the epithelial-mesenchymal transition (EMT) concept, a critical process during embryonic morphogenesis and carcinoma progression, has offered a mechanistic explanation for the phenotypic switch of cancer cells upon PBD exposure. Accumulating evidence has suggested that carcinoma cells can enter a resistant state via induction of the EMT. In this review, we discussed the underlying mechanism of PBD-induced EMT and the current understanding of its role in cancer drug resistance, with emphasis on how this novel knowledge can be exploited to overcome PBD resistance via EMT-targeted compounds, especially those under clinical trials.

Inhibition and potential treatment of colorectal cancer by natural compounds via various signaling pathways

Colorectal cancer (CRC) is a common type of malignant digestive tract tumor with a high incidence rate worldwide. Currently, the clinical treatment of CRC predominantly include surgical resection, postoperative chemotherapy, and radiotherapy. However, these treatments contain severe limitations such as drug side effects, the risk of recurrence and drug resistance. Some natural compounds found in plants, fungi, marine animals, and bacteria have been shown to inhibit the occurrence and development of CRC. Although the explicit molecular mechanisms underlying the therapeutic effects of these compounds on CRC are not clear, classical signaling transduction pathways such as NF-kB and Wnt/β-catenin are extensively regulated. In this review, we have summarized the specific mechanisms regulating the inhibition and development of CRC by various types of natural compounds through nine signaling pathways, and explored the potential therapeutic values of these natural compounds in the clinical treatment of CRC.

Using ncRNAs as Tools in Cancer Diagnosis and Treatment-The Way towards Personalized Medicine to Improve Patients' Health

Although the first discovery of a non-coding RNA (ncRNA) dates back to 1958, only in recent years has the complexity of the transcriptome started to be elucidated. However, its components are still under investigation and their identification is one of the challenges that scientists are presently facing. In addition, their function is still far from being fully understood. The non-coding portion of the genome is indeed the largest, both quantitatively and qualitatively. A large fraction of these ncRNAs have a regulatory role either in coding mRNAs or in other ncRNAs, creating an intracellular network of crossed interactions (competing endogenous RNA networks, or ceRNET) that fine-tune the gene expression in both health and disease. The alteration of the equilibrium among such interactions can be enough to cause a transition from health to disease, but the opposite is equally true, leading to the possibility of intervening based on these mechanisms to cure human conditions. In this review, we summarize the present knowledge on these mechanisms, illustrating how they can be used for disease treatment, the current challenges and pitfalls, and the roles of environmental and lifestyle-related contributing factors, in addition to the ethical, legal, and social issues arising from their (improper) use.

PPARGC1A affects inflammatory responses in photodynamic therapy (PDT)-treated inflammatory bowel disease (IBD)

BACKGROUND

Chronic inflammation of the gastrointestinal tract is a feature of inflammatory bowel disease (IBD), including Crohn's disease (CD) and ulcerative colitis (UC). Targeting inflammatory signaling represents promising strategy for IBD treatment regimens.

METHODS

Dextran sulfate sodium (DSS)-induced colitis model was established in mice. Histopathological examinations were conducted by H&E staining and IHC staining. IL-1β, IL-10, and TNF-α were tested by ELISA kits. TargetScan was used to predict miRNAs that target PPARGC1A and luciferase activity assay was performed to validate the predicted binding.

RESULTS

DSS-induced acute colitis model was successfully established in mice; photodynamic therapy (PDT) treatment partially improved DSS-induced colonic damages and cell inflammation. Microarray assays and integrative bioinformatics analysis identified PPARG coactivator 1 alpha (PPARGC1A) as a significantly differentially-expressed gene in PDT-treated IBD compared with non-treated IBD. PPARGC1A expression was downregulated in IBD clinical samples, DSS-induced colitis mice colons, and DSS-stimulated colonic epithelial cells, whereas partially upregulated by PDT treatment in DSS-stimulated cells. Single DSS stimulation significantly promoted cellular inflammation; PDT partially attenuated, whereas sh-PPARGC1A transduction further enhanced DSS effects on cancer cell inflammation. In colitis mice, DSS decreased PPRA-α and PPRA-γ proteins in mice colons; the in vivo effects of DSS were partially attenuated by PDT treatment, whereas amplified by sh-PPARGC1A transduction. Upstream miR-301a-3p targeted and inhibited PPARGC1A expression.

CONCLUSIONS

Collectively, PPARGC1A, which is downregulated in DSS-induced acute colitis and DSS-stimulated colonic epithelial cells, could be upregulated by PDT treatment. PPARGC1A knockdown could attenuate PDT therapeutic effects on DSS-induced acute colitis and DSS-stimulated colonic epithelial cells.

Utility of Indian fruits in cancer prevention and treatment: Time to undertake translational and bedside studies

The World Health Organization predicts a 70% increase in cancer incidents in developing nations over the next decade, and it will be the second leading cause of death worldwide. Traditional plant-based medicine systems play an important role against various diseases and provide health care to a large section of the population in developing countries. Indigenous fruits and their bioactive compounds with beneficial effects like antioxidant, antiproliferative, and immunomodulatory are shown to be useful in preventing the incidence of cancer. India is one of the biodiversity regions and is native to numerous flora and fauna in the world. Of the many fruiting trees indigenous to India, Mango (Mangifera indica), Black plum (Eugenia jambolana or Syzygium jambolana), Indian gooseberry (Emblica officinalis or Phyllanthus emblica), kokum (Garcinia indica or Brindonia indica), stone apple or bael (Aegle marmelos), Jackfruit (Artocarpus heterophyllus), Karaunda (Carissa carandas) and Phalsa (Grewia asiatica), Monkey Jackfruit (Artocarpus lakoocha) and Elephant apple (Dillenia indica) have been shown to be beneficial in preventing cancer and in the treatment of cancer in validated preclinical models of study. In this review, efforts are also made to collate the fruits' anticancer effects and the important phytochemicals. Efforts are also made at emphasizing the underlying mechanism/s responsible for the beneficial effects in cancer prevention and treatment. These fruits have been a part of the diet, are non-toxic, and easily acceptable for human application. The plants and some of their phytochemicals possess diverse medicinal properties. The authors propose that future studies should be directed at detailed studies with various preclinical models of study with both composite fruit extract/juice and the individual phytochemicals. Additionally, translational studies should be planned with the highly beneficial, well-investigated and pharmacologically multifactorial amla to understand its usefulness as a cancer preventive in the high-risk population and as a supportive agent in cancer survivors. The outcome of both preclinical and clinical studies will be useful for patients, the healthcare fraternity, pharmaceutical, and agro-based sectors.

Bioactive food components for colorectal cancer prevention and treatment: A good match

Colorectal cancer (CRC) is the third most frequent cancer worldwide, accounts for about 10% of the total cancer cases, and ranks as the second cause of death by cancer. CRC is more prevalent in developed countries in close causal relation with occidental diets. Due to anatomy, the diet has a strong impact on CRC. High contents in meat are acknowledged risk factors whereas a diet rich in fruits and vegetables is an established CRC protective factor. Fruits and vegetables contain numerous Bioactive Food Components (BFCs), physiologically active food compounds, beneficial on health. Preventive and therapeutic benefits of BFCs in cancer have increasingly been reported over the past 20 years. BFCs show both chemopreventive and anti-tumor properties in CRC but more interestingly, abundant research describes BFCs as enhancers of conventional cancer treatments. Despite these promising results, their clinical transferability is slowed down by bioavailability interrogations and their poorly understood hormetic effect. In this review, we would like to reposition BFCs as well-fitted for applications in CRC. We provide a synthetic overview of trustworthy BFC applications in CRC, with a special highlight on combinatory approaches and conventional cancer treatment potentiation strategies.