Molecular mechanisms for chemoprevention of colorectal cancer by natural dietary 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.

The Neuroprotective Role of Tangeritin

The prevalence of neurodegenerative diseases has increased with longer life expectancies, necessitating the exploration of novel neuroprotective agents. Tangeretin, a polymethoxylated flavone derived from citrus fruits, has gathered attention for its potential therapeutic effects. This review highlights the neuroprotective properties of tangeretin via its antioxidant and anti-inflammatory mechanisms. Tangeretin demonstrates efficacy in mitigating oxidative stress, neuroinflammation, and neuronal damage across various neurodegenerative conditions, including Alzheimer's disease, Parkinson's disease, cerebral ischemia, and epilepsy. It shows promise in ameliorating cognitive deficits and memory impairments associated with these diseases. Moreover, tangeretin modulates multiple signalling pathways and protects against neuronal apoptosis, underscoring its potential as a therapeutic agent.

Comprehensive Insights Into the Combinatorial Uses of Selected Phytochemicals in Colorectal Cancer Prevention and Treatment: Isothiocyanates, Quinones, Carotenoids, and Alkaloids

Despite the advancement in cancer diagnosis and treatment, colorectal cancer remains the leading cause of cancer-related death worldwide. Given the high recurrence rate of colorectal cancer even after surgical resection, chemotherapy has been clinically used to improve the treatment outcomes of colorectal cancer. However, chemotherapy is well-known for its toxic side effects. Thus, phytochemicals have been widely studied in recent years as preventive and therapeutic agents for colorectal cancer owing to their relatively low toxicity. Moreover, combinatorial uses of phytochemicals with other natural compounds or with drugs may amplify the positive outcomes of colorectal cancer prevention and treatment by intervening in multiple signaling pathways and targets. This review summarized the combinatorial use of several well-studied groups of phytochemicals, that is, isothiocyanates, quinones, carotenoids, and alkaloids, in the prevention and treatment of colorectal cancer, and suggested it as a potential approach to improve the anticancer efficacy of single compounds and minimize the toxic side effects associated with conventional drugs. Notably, we generalized the in vitro, in vivo, and clinical experiments-based molecular mechanisms whereby the selected phytochemicals in combination with other compounds exerted anti-colorectal cancer effects by inhibiting cancer cell proliferation, cell apoptosis, cell invasion, and tumor growth. Overall, this review provides a reference and new perspective to propel further advancements in research and development of preventative and therapeutic strategies for colorectal cancer.

Prognostic Nutritional Index is Related to All-Cause Mortality in Patients With Stage IV Colorectal Cancer Treated With Capecitabine: Single-Center 24-Month Observational Study in Vietnam

AIM

To determine the mortality rate and the predictive value of the prognostic nutritional index (PNI) for all-cause mortality during the 24 months in patients with stage IV colorectal cancer treated with capecitabine.

METHODS

We conducted a study on 87 stage IV colorectal cancer patients treated with capecitabine. Before the day of treatment, all patients were measured CEA and CRP-hs levels and calculated neutrophil/lympho ratio (NLR) and PNI. Patients were monitored and collected drug side effects and mortality for 24 months.

RESULTS

The mortality rate of study subjects was 60.9%. CRP-hs, NLR, and PNI were independent factors associated with 24-month mortality in patients with stage IV colorectal cancer (p < 0.05 to p < 0.01). At a cut-off value of 38.51, PNI was a predictor for mortality, with the area under the curve (AUC) of 0.88 and p < 0.001.

CONCLUSIONS

PNI was a good predictor of all-cause mortality in patients with stage IV colorectal cancer treated with capecitabine for 24 months.

Effect of dark chocolate/ cocoa consumption on oxidative stress and inflammation in adults: A GRADE-assessed systematic review and dose-response meta-analysis of controlled trials

BACKGROUND

Oxidative stress and inflammation play critical roles in the pathogenesis of many chronic diseases. Dark chocolate (DC)/cocoa, as a rich source of polyphenols like flavonoids, has anti-inflammatory and antioxidant properties that may confer health benefits, but findings in this context are inconsistent.

OBJECTIVE

This systematic review and dose-response meta-analysis aimed to provide a comprehensive overview of the controlled trials (CTs) that have examined the effects of DC/cocoa on oxidative stress and inflammation biomarkers in adults.

SEARCH METHODS

Databases including PubMed, Web of Science, and Scopus, were searched for relevant studies through April 2024.

SELECTION CRITERIA

Studies assessed C-reactive protein (CRP), interleukin-6 (IL-6), tumor necrosis factor-alpha (TNF-α), malondialdehyde (MDA), nitric oxide (NO), P-selectin, E-selectin and thiobarbituric acid reactive substances (TBARS) in adults were included.

DATA ANALYSIS

Based on the random-effects model, we calculated WMDs, SMDs and 95 % confidence intervals (CIs). Sensitivity, sub-group, meta-regression and dose-response analyses were also conducted.

RESULTS

Thirty-three eligible CTs with 1379 participants were included. All studies reported the intervention types (cocoa powder, beverages and chocolate bars) and dosage. However, sixteen studies didn't do/report testing for purity and potency by independent groups. Also, none of the studies mentioned the risk of contamination with heavy metals. Another limitation was the lack of blinding assessment in studies. DC/cocoa significantly reduced MDA (SMD: -0.69, 95 %CI: -1.17, -0.2, p = 0.005) and increased NO levels (SMD: 2.43, 95 %CI: 1.11,3.75, p < 0.001); However, it has no significant effects on the other outcomes. Greater anti-inflammatory effects occurred at higher flavonoid doses (>450 mg/day) and for shorter durations (≤4 weeks) in the non-healthy participants. Non-linear dose-response relationships between cocoa dosage and CRP level and also between flavonoid dosage and IL-6 level were observed. Based on the GRADE evaluation, just CRP and MDA results were considered as high certainty evidence and the other outcomes results were categorized as very low to moderate certainty.

CONCLUSIONS

DC/cocoa may improve systemic oxidative status and inflammation in adults. However, further studies should be performed to determine its benefits.

Tumoricidal properties of thymoquinone on human colorectal adenocarcinoma cells via the modulation of autophagy

Colorectal cancer (CRC) is deadly anaplastic changes in the gastrointestinal tract with high-rate mortality. In recent years, the application of phytocompounds has been extended along with different therapeutic protocols. Here, we monitored the effects of Thymoquinone (TQ) on autophagy via mitochondrial function after modulation of the Wnt/β-catenin signaling pathway.Human colorectal adenocarcinoma HT-29 cells were treated with TQ (60 µM) and 15 µM Wnt3a inhibitor (LGK974) for 48 h. The survival rate was evaluated using an MTT assay. The expression of Wnt-related factors (c-Myc, and Axin), angiogenesis (VE-Cadherin), and mitophagy-related factors (PINK1, OPTN) was assessed using real-time PCR assay. Protein levels of autophagy factors (Beclin-1, LC3, and P62) were monitored using western blotting. Using flow cytometry analysis, the intracellular accumulation of Rhodamine 123 was evaluated. The migration properties were analyzed using a scratch wound healing assay.Data indicated that TQ can reduce the viability of HT-29 cells compared to the control cells (p < 0.05). The expression of VE-Cadherin was inhibited while the expression of PINK1 was induced in treated cells (p < 0.05). Both LGK974 and TQ-treated cells exhibited activation of autophagy flux (Beclin-1↑, LC3II/I↑, and p62↓) compared to the control group (p < 0.05). TQ can increase intracellular accumulation of Rhodamine 123, indicating the inhibition of efflux mechanisms in cancer cells. Along with these changes, the migration of cells was also reduced (p < 0.05).TQ is a potential phytocompound to alter the dynamic growth of human colorectal HT-29 cells via the modulation of autophagy, and mitophagy-related mechanisms.

Management of Colorectal Cancer Using Nanocarriers-based Drug Delivery for Herbal Bioactives: Current and Emerging Approaches

Colorectal cancer (CRC) is a complex and multifactorial disorder in middle-aged people. Several modern medicines are available for treating and preventing it. However, their therapeutic uses are limited due to drawbacks, such as gastric perforation, diarrhea, intestinal bleeding, abdominal cramps, hair loss, nausea, vomiting, weight loss, and adverse reactions. Hence, there is a continuous quest for safe and effective medicines to manage human health problems, like CRC. In this context, herbal medicines are considered an alternative disease control system. It has become popular in countries, like American, European, and Asian, due to its safety and effectiveness, which has been practiced for 1000 years. During the last few decades, herbal medicines have been widely explored through multidisciplinary fields for getting active compounds against human diseases. Several herbal bioactives, like curcumin, glycyrrhizin, paclitaxel, chlorogenic acid, gallic acid, catechin, berberine, ursolic acid, betulinic acid, chrysin, resveratrol, quercetin, etc., have been found to be effective against CRC. However, their pharmacological applications are limited due to low bioavailability and therapeutic efficacy apart from their several health benefits. An effective delivery system is required to increase their bioavailability and efficacy. Therefore, targeted novel drug delivery approaches are promising for improving these substances' solubility, bioavailability, and therapeutic effects. Novel carrier systems, such as liposomes, nanoparticles, micelles, microspheres, dendrimers, microbeads, and hydrogels, are promising for delivering poorly soluble drugs to the target site, i.e., the colon. Thus, the present review is focused on the pathophysiology, molecular pathways, and diagnostic and treatment approaches for CRC. Moreover, an emphasis has been laid especially on herbal bioactive-based novel delivery systems and their clinical updates.

The preventive and therapeutic effects of anthocyanins on colorectal cancer: A comprehensive review based on up-to-date experimental studies

Colorectal cancer (CRC) is the second most lethal and the third most diagnosed type of cancer worldwide. More than 75% of CRC cases are sporadic and lifestyle-related. Risk factors include diet, physical inactivity, genetics, smoking, alcohol, changes in the intestinal microbiota, and inflammation-related diseases such as obesity, diabetes, and inflammatory bowel diseases. The limits of conventional treatments (surgery, chemotherapy, radiotherapy), as demonstrated by the side effects and resistance of many CRC patients, are making professionals search for new chemopreventive alternatives. In this context, diets rich in fruits and vegetables or plant-based products, which contain high levels of phytochemicals, have been postulated as complementary therapeutic options. Anthocyanins, phenolic pigments responsible for the vivid colors of most red, purple, and blue fruits and vegetables, have been shown protective effects on CRC. Berries, grapes, Brazilian fruits, and vegetables such as black rice and purple sweet potato are examples of products rich in anthocyanins, which have been able to reduce cancer development by modulating signaling pathways associated with CRC. Therefore, this review has as main objective to present and discuss the potential preventive and therapeutic effects of anthocyanins present in fruits and vegetables, in plant extracts, or in their pure form on CRC, taking into account up-to-date experimental studies (2017-2023). Additionally, a highlight is given towards the mechanisms of action of anthocyanins on CRC.

Calebin A targets the HIF-1α/NF-κB pathway to suppress colorectal cancer cell migration

Background: Hypoxia-inducible factor-1α (HIF-1α) is one of the major tumor-associated transcription factors modulating numerous tumor properties such as tumor cell metabolism, survival, proliferation, angiogenesis, and metastasis. Calebin A (CA), a compound derived from turmeric, is known for its anti-cancer activity through modulation of the NF-κB pathway. However, its impact on HIF-1α in colorectal cancer (CRC) cell migration is unknown. Methods: Human CRC cells (HCT-116) in 3D alginate and monolayer multicellular TME (fibroblasts/T lymphocytes) were subjected to CA or the HIF-1α inhibitor to explore the efficacy of CA on TME-induced inflammation, migration, and tumor malignancy. Results: CA significantly inhibited TME-promoted proliferation and migration of HCT-116 cells, similar to the HIF-1α inhibitor. Colony formation, toluidine blue staining, and immunolabeling showed that CA inhibited the migration of HCT-116 cells partly by inhibiting HIF-1α, which is critical for CRC cell viability, and these observations were confirmed by electron microscopy. In addition, Western blot analysis confirmed that CA inhibited TME-initiated expression of HIF-1α and biomarkers of metastatic factors (such as NF-κB, β1-integrin, and VEGF), and promoted apoptosis (caspase-3), in a manner comparable to the HIF-1α inhibitor. Finally, TME induced a purposeful pairing between HIF-1α and NF-κB, suggesting that the synergistic interplay between the two tumor-associated transcription factors is essential for CRC cell malignancy and migration and that CA silences these factors in tandem. Conclusion: These results shed light on a novel regulatory modulation of CA signaling in CRC cell migration, partially via HIF-1α/NF-κB with potentially relevant implications for cancer therapy.

Intensification of resveratrol cytotoxicity, pro-apoptosis, oxidant potentials in human colorectal carcinoma HCT-116 cells using zein nanoparticles

Resveratrol (RSV), a non-flavonoid stilbene polyphenol, possesses anti-carcinogenic activities against all the major stages of cancer. Zein nanoparticles (ZN NPs) have been utilized successfully in delivery of variant therapeuticals by virtue of their histocompatible nature. The goal of this work was to comparatively explore the antiproliferative, pro-apoptotic and oxidative stress potentials of RSV-ZN NPs versus RSV against human colorectal carcinoma HCT-116 cells. ZN-RSV NPs were developed and assayed for particle size analysis and RSV diffusion. The selected formula obtained 137.6 ± 8.3 nm as mean particle size, 29.4 ± 1.8 mV zeta potential, 92.3 ± 3.6% encapsulation efficiency. IC₅₀ of the selected formula was significantly lower against HCT-116 cells versus Caco-2 cells. Also, significantly enhanced cellular uptake was generated from RSV-ZN NPs versus free RSV. Enhanced apoptosis was concluded due to increased percentage cells in G2-M and pre-G1 phases. The pro-apoptotic potential was explained by caspase-3 and cleaved caspase-3 increased mRNA expression in addition to NF-κB and miRNA125b decreased expression. Biochemically, ZN-RSV NPs induced oxidative stress as demonstrated by enhanced reactive oxygen species (ROS) generation and endothelial nitric oxide synthase (eNOS) isoenzyme increased levels. Conclusively, ZN-RSV NPs obtained cell cycle inhibition supported with augmented cytotoxicity, uptake and oxidative stress markers levels in HCT-116 tumor cells in comparison with free RSV. These results indicated intensified chemopreventive profile of RSV due to effective delivery utilizing ZN nano-dispersion against colorectal carcinoma HCT-116 cells.

Prediagnostic plasma polyphenol concentrations and colon cancer risk: The JPHC nested case-control study

BACKGROUND & AIMS

Epidemiological studies that assessed the associations between dietary polyphenol intakes and colon cancer risk have reported largely null results, possibly due to measurement error associated with dietary assessment. We adopted an objective approach by measuring prediagnostic plasma concentrations of 35 polyphenols and assessing associations with colon cancer risk.

METHODS

We conducted a nested-case control study within the Japan Public Health Center-based prospective study (JPHC Study) utilizing plasma samples collected at the time of a five-year follow-up survey between 1995 and 1999. We identified colon cancer cases who developed cancer during the follow-up from the time of blood collection. Controls were matched by age, sex, area code, population size of the area, season of blood collection, year of blood collection, and duration of fasting time before the blood collection. Prediagnostic concentrations of 35 polyphenols from 375 incident colon cancer cases (followed until 2012) and 710 matched controls were measured by tandem mass spectrometry coupled with ultra-high-pressure liquid chromatography. We used multivariable conditional logistic regression models adjusted for established colon cancer risk factors to estimate odds ratios (ORs) and 95% confidence intervals (CIs).

RESULTS

In sexes combined log2-transformed multivariable models, circulating levels of 3,4-dihydroxyphenylpropionic acid (P = 0.02), ferulic acid (P = 0.02), and caffeic acid (P = 0.03) were inversely, and 3-hydroxybenzoic acid (P = 0.03) was positively, associated with colon cancer risk. For men only, circulating levels of 3,4-dihydroxyphenylpropionic acid was inversely, and 3,5-dihydroxyphenylpropionic acid, gallic acid, (+)-epigallocatechin, 3-hydroxybenzoic acid, and epicatechin were positively, associated with colon cancer risk. In women, plasma caffeic acid and ferulic acid concentration were inversely associated with colon cancer risk. However, all these associations were nonsignificant after adjustment for multiple comparisons. The remaining polyphenols were not associated with colon cancer risk.

CONCLUSION

Coffee-derived 3,4-dihydroxyphenylpropionic acid, ferulic acid, and caffeic acid concentrations were inversely associated with colon cancer risk although the association were nonsignificant after adjustment for multiple comparisons. These results support a possible role of coffee polyphenols in preventing colorectal cancer.

Anti-cancer effects of fenbendazole on 5-fluorouracil-resistant colorectal cancer cells

Benzimidazole anthelmintic agents have been recently repurposed to overcome cancers resistant to conventional therapies. To evaluate the anti-cancer effects of benzimidazole on resistant cells, various cell death pathways were investigated in 5-fluorouracil-resistant colorectal cancer cells. The viability of wild-type and 5-fluorouracil-resistant SNU-C5 colorectal cancer cells was assayed, followed by Western blotting. Flow cytometry assays for cell death and cell cycle was also performed to analyze the anti-cancer effects of benzimidazole. When compared with albendazole, fenbendazole showed higher susceptibility to 5-fluorouracil-resistant SNU-C5 cells and was used in subsequent experiments. Flow cytometry revealed that fenbendazole significantly induces apoptosis as well as cell cycle arrest at G2/M phase on both cells. When compared with wild-type SNU-C5 cells, 5-fluorouracil-resistant SNU-C5 cells showed reduced autophagy, increased ferroptosis and ferroptosis-augmented apoptosis, and less activation of caspase-8 and p53. These results suggest that fenbendazole may be a potential alternative treatment in 5-fluorouracil-resistant cancer cells, and the anticancer activity of fenbendazole does not require p53 in 5-fluorouracil-resistant SNU-C5 cells.

The histidine phosphatase LHPP: an emerging player in cancer

Cancers continue to have high incidence and mortality rates worldwide. Therefore, cancer control remains the main public health goal. Growing research evidence suggests that phospholysine phosphohistidine inorganic pyrophosphate phosphatase (LHPP) plays an important role in inhibiting tumor cell progression. It has been reported in the literature that LHPP is expressed at low levels in tumor tissues and cells and that patients with low LHPP expression have a poorer prognosis. Functional studies have shown that LHPP can inhibit tumor cell proliferation, metastasis, and apoptosis by affecting different target genes. In addition, researchers have used iDPP nanoparticles to deliver LHPP plasmids to treat tumors, demonstrating the great potential of LHPP plasmids for cancer therapy. In our review, we highlight the biological functions and important downstream target genes of LHPP in tumors, providing a theoretical basis for the treatment of human cancers. Although not thoroughly studied in terms of tumor mechanisms, LHPP still represents a promising and effective anticancer drug target.

Luteolin Causes 5'CpG Demethylation of the Promoters of TSGs and Modulates the Aberrant Histone Modifications, Restoring the Expression of TSGs in Human Cancer Cells

Cancer progression is linked to abnormal epigenetic alterations such as DNA methylation and histone modifications. Since epigenetic alterations, unlike genetic changes, are heritable and reversible, they have been considered as interesting targets for cancer prevention and therapy by dietary compounds such as luteolin. In this study, epigenetic modulatory behaviour of luteolin was analysed on HeLa cells. Various assays including colony forming and migration assays, followed by biochemical assays of epigenetic enzymes including DNA methyltransferase, histone methyl transferase, histone acetyl transferase, and histone deacetylases assays were performed. Furthermore, global DNA methylation and methylation-specific PCR for examining the methylation status of CpG promoters of various tumour suppressor genes (TSGs) and the expression of these TSGs at transcript and protein level were performed. It was observed that luteolin inhibited migration and colony formation in HeLa cells. It also modulated DNA methylation at promoters of TSGs and the enzymatic activity of DNMT, HDAC, HMT, and HAT and reduced the global DNA methylation. Decrease in methylation resulted in the reactivation of silenced tumour suppressor genes including FHIT, DAPK1, PTEN, CDH1, SOCS1, TIMPS, VHL, TP53, TP73, etc. Hence, luteolin-targeted epigenetic alterations provide a promising approach for cancer prevention and intervention.

Reckoning apigenin and kaempferol as a potential multi-targeted inhibitor of EGFR/HER2-MEK pathway of metastatic colorectal cancer identified using rigorous computational workflow

In the past two decades, the treatment of metastatic colorectal cancer (mCRC) has been revolutionized as multiple cytotoxic, biological, and targeted drugs are being approved. Unfortunately, tumors treated with single targeted agents or therapeutics usually develop resistance. According to pathway-oriented screens, mCRC cells evade EGFR inhibition by HER2 amplification and/or activating Kras-MEK downstream signaling. Therefore, treating mCRC patients with dual EGFR/HER2 inhibitors, MEK inhibitors, or the combination of the two drugs envisaged to prevent the resistance development which eventually improves the overall survival rate. In the present study, we aimed to screen potential phytochemical lead compounds that could multi-target EGFR, HER2, and MEK1 (Mitogen-activated protein kinase kinase) using a computer-aided drug design approach that includes molecular docking, endpoint binding free energy calculation using MM-GBSA, ADMET, and molecular dynamics (MD) simulations. Docking studies revealed that, unlike all other ligands, apigenin and kaempferol exhibit the highest docking score against all three targets. Details of ADMET analysis, MM/GBSA, and MD simulations helped us to conclusively determine apigenin and kaempferol as potentially an inhibitor of EGFR, HER2, and MEK1 apigenin and kaempferol against mCRC at a systemic level. Additionally, both apigenin and kaempferol elicited antiangiogenic properties in a dose-dependent manner. Collectively, these findings provide the rationale for drug development aimed at preventing CRC rather than intercepting resistance.

The PI3K/Akt/mTOR axis in colorectal cancer: Oncogenic alterations, non-coding RNAs, therapeutic opportunities, and the emerging role of nanoparticles

Colorectal cancer (CRC) is one of the deadliest human malignancies worldwide. Several molecular pathways have been demonstrated to be involved in the initiation and development of CRC which among them, the overactivation of the phosphatidyl-inositol 3-kinase (PI3K)/Akt/mTOR axis is of importance. The current review aims to unravel the mechanisms by which the PI3K/Akt/mTOR pathway affects CRC progression; and also, to summarize the original data obtained from international research laboratories on the oncogenic alterations and polymorphisms affecting this pathway in CRC. Besides, we provide a special focus on the regulatory role of noncoding RNAs targeting the PI3K/Akt/mTOR pathway in this malignancy. Questions on how this axis is involved in the inhibition of apoptosis, in the induction of drug resistance, and the angiogenesis, epithelial to mesenchymal transition, and metastasis are also responded. We also discussed the PI3K/Akt pathway-associated prognostic and predictive biomarkers in CRC. In addition, we provide a general overview of PI3K/Akt/mTOR pathway inhibition whether by chemical-based drugs or by natural-based medications in the context of CRC, either as monotherapy or in combination with other therapeutic agents; however, those treatments might have life-threatening side effects and toxicities. To the best of our knowledge, the current review is one of the first ones highlighting the emerging roles of nanotechnology to overcome challenges related to CRC therapy in the hope that providing a promising platform for the treatment of CRC.

Anti-cancer effects of the aqueous extract of Orostachys japonica A. Berger on 5-fluorouracil-resistant colorectal cancer via MAPK signalling pathways in vitro and in vivo

ETHNOPHARMACOLOGICAL RELEVANCE

Orostachys japonica A. Berger, also known as Wa-song in Korea, has traditionally been used as a folk medicine, but the potential anti-cancer effects of aqueous extract of Orostachys japonica (OJe) have not yet been thoroughly investigated.

AIM OF THE STUDY

To evaluate the anti-cancer effects of OJe, its possible mechanisms of action were investigated in 5-fluorouracil (5-FU) resistant SNU-C5/5-FUR colorectal cancer cells.

MATERIALS AND METHODS

The functional compounds of OJe were identified with high performance liquid chromatography. The anti-cancer effects of OJe in SNU-C5/5-FUR cells were investigated by a cell viability assays, flow cytometry analysis, and a subcutaneous xenograft model employing BALB/c-nude mice. Possible signalling pathways were assayed with Western blotting.

RESULTS

OJe (250 μg/ml) showed anti-cancer effects in SNU-C5/5-FUR cells, that were mediated via apoptosis as well as cell cycle arrest at the G0/G1 phase. Gallic acid and (-)-epicatechin, the major functional components of OJe, induced cell cycle arrest. OJe treatment (250 mg/kg, p.o.) produced a significant anti-proliferative effect in the xenograft model via decreased β-catenin/GSK3β and increased p27 expression. OJe treatment significantly activated ERK and p38 both in vitro and in vivo.

CONCLUSIONS

These results suggest that OJe has anti-proliferative effects on 5-FU-resistant colorectal cancer cells via regulation of MAPK signalling pathways.

Recent Updates on Marine Cancer-Preventive Compounds

The natural compounds derived from marine organisms often exhibit unique chemical structures and potent biological activities. Cancer-preventive activity is one of the rather new activities that has emerged and been extensively studied over the last decades. This review summarizes the recent updates on the marine chemopreventive compounds covering the relevant literature published in 2013-2021 and following the previous comprehensive review by Stonik and Fedorov (Marine Drugs 2014, 12, 636-671). In the current article, only the molecules having an effect on malignant transformation (or related pathway and molecules), cancer stem cells, or carcinogen-induced in vivo tumor development were considered to be "true" cancer-preventive compounds and were, therefore, reviewed. Additionally, particular attention has been given to the molecular mechanisms of chemoprevention, executed by the reported marine compounds.

Cancer Therapy Challenge: It Is Time to Look in the "St. Patrick's Well" of the Nature

Cancer still remains a leading cause of death despite improvements in diagnosis, drug discovery and therapy approach. Therefore, there is a strong need to improve methodologies as well as to increase the number of approaches available. Natural compounds of different origins (i.e., from fungi, plants, microbes, etc.) represent an interesting approach for fighting cancer. In particular, synergistic strategies may represent an intriguing approach, combining natural compounds with classic chemotherapeutic drugs to increase therapeutic efficacy and lower the required drug concentrations. In this review, we focus primarily on those natural compounds utilized in synergistic approached to treating cancer, with particular attention to those compounds that have gained the most research interest.

Benefits of Polyphenols and Methylxanthines from Cocoa Beans on Dietary Metabolic Disorders

Theobroma cacao L. is an ancestral cultivated plant which has been consumed by various populations throughout history. Cocoa beans are the basic material occurring in the most consumed product in the world, namely chocolate. Their composition includes polyphenols, methylxanthines, lipids and other compounds that may vary qualitatively and quantitatively according to criteria such as variety or culture area. Polyphenols and methylxanthines are known as being responsible for many health benefits, particularly by preventing cardiovascular and neurodegenerative diseases. Recent studies emphasized their positive role in dietary metabolic disorders, such as diabetes and weight gain. After a brief presentation of cocoa bean, this review provides an overview of recent research activities highlighting promising strategies which modulated and prevented gastro-intestinal metabolism dysfunctions.

Enhancement of Anticancer Potential of Pterostilbene Derivative by Chalcone Hybridization

Pterostilbene, a natural metabolite of resveratrol, has been indicated as a potent anticancer molecule. Recently, several pterostilbene derivatives have been reported to exhibit better anticancer activities than that of the parent pterostilbene molecule. In the present study, a series of pterostilbene derivatives were designed and synthesized by the hybridization of pterostilbene, chalcone, and cinnamic acid. The cytotoxic effect of these hybrid molecules was determined using two oral cancer cell lines, HSC-3 and OECM-1. (E)-3-(2-((E)-4-Hydroxystyryl)-4,6-dimethoxyphenyl)-1-(2-methoxyphenyl)prop-2-en-1-one (4d), with IC₅₀ of 16.38 and 18.06 μM against OECM-1 and HSC-3, respectively, was selected for further anticancer mechanism studies. Results indicated that compound 4d effectively inhibited cell proliferation and induced G2/M cell cycle arrest via modulating p21, cyclin B1, and cyclin A2. Compound 4d ultimately induced cell apoptosis by reducing the expression of Bcl-2 and surviving. In addition, cleavage of PARP and caspase-3 were enhanced following the treatment of compound 4d with increased dose. To conclude, a number of pterostilbene derivatives were discovered to possess potent anticancer potentials. Among them, compound 4d was the most active, more active than the parent pterostilbene.

Styrax camporum, a typical species of the Brazilian cerrado, attenuates DNA damage, preneoplastic lesions and oxidative stress in experimental rat colon carcinogenesis

Styrax camporum Pohl, a typical species from the Brazilian cerrado, commonly known as "benjoeiro", is used to treat gastroduodenal diseases. In previous studies carried out by our research group, hydroalcoholic extract of S. camporum stems (SCHE) exhibited antigenotoxic and antiproliferative effects. For a comparative analysis of the chemopreventive effect of SCHE, the aim of this study was to investigate the influence of SCHE against carcinogen 1,2-dimethylhydrazine (DMH)-induced DNA damage and pre-neoplastic lesions in Wistar rat colon. Animals were treated orally with SCHE at 250, 500 or 1000 mg/kg body weight in conjunction with a subcutaneous injection of DMH. DNA damage was assessed using the comet assay while tpre-neoplastic lesions by aberrant crypt foci (ACF) assay. The following hepatic oxidative stress markers were determined including activities of catalase (CAT) and glutathione S-transferase (GST) as well as levels of reduced glutathione (GSH) and malondialdehyde (MDA). Treatment with SCHE was not genotoxic or carcinogenic at the highest dose tested (1000 mg/kg b.w.). The extract effectively inhibited DNA damage and pre-neoplastic lesions induced by DMH administration at all concentrations tested. Measurement of CAT, and GST activities and levels of GSH showed that SCHE did not reduce oxidative processes. In contrast, treatment with SCHE (1000 mg/kg b.w.) decreased liver MDA levels. Taken together, these findings suggested the chemopreventive effect attributed to SCHE in colon carcinogenesis, may be related to its capacity to inhibit DNA damage as well as an antioxidant action associated with its chemical constituents egonol and homoegonol.

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

BACKGROUND

Colorectal cancer (CRC) is considered one of the most predominant and deadly cancer globally. Nowadays, the main clinical management for this cancer includes chemotherapy and surgery; however, these treatments result in the occurrence of drug resistance and severe side effects, and thus it is a crucial requirement to discover an alternative and potential therapy for CRC treatment. Numerous therapeutic cancers were initially recognized from natural metabolites utilized in traditional medicine, and several recent types of research have shown that many natural products own potential effects against CRC and may assist the action of chemotherapy for the treatment of CRC. It has been indicated that most patients are well tolerated by natural compounds without showing any toxicity signs even at high doses. Conventional chemotherapeutics interaction with natural medicinal compounds presents a new feature in cancer exploration and treatment. Most of the natural compounds overwhelm malignant cell propagation by apoptosis initiation of CRC cells and arresting of the cell cycle (especially at G, S, and G2/M phase) that result in inhibition of tumor growth.

OBJECTIVE

This mini-review aimed to focus on natural compounds (alkaloids, flavonoids, polysaccharides, polyphenols, terpenoids, lactones, quinones, etc.) that were identified to have anti- CRC activity in vitro on CRC cell lines and/or in vivo experiments on animal models.

CONCLUSION

Most of the studied active natural compounds possess anti-CRC activity via different mechanisms and pathways in vitro and in vivo that might be used as assistance by clinicians to support chemotherapy therapeutic strategy and treatment doses for cancer patients.

Azoxymethane-Induced Colorectal Cancer Mice Treated with a Polyphenol-Rich Apple Extract Show Less Neoplastic Lesions and Signs of Cachexia

Obesity is considered a risk factor for the development of colorectal cancer. In rodents, high-fat (HF) diets are able to increase the formation of azoxymethane (AOM)-induced polyps. Polyphenol-rich apple extracts have antioxidant and anti-inflammatory activities and may induce an amelioration of the manifestations of colorectal cancer. Twenty-seven male Crl:CD-1 mice received AOM during four weeks and were subsequently divided into three groups fed a HF diet (n = 9 each group): a non-supplemented group, a second group supplemented with apple extract at 1%, and a third group supplemented with the same apple extract at 1.5%. Energy metabolism and the respiratory quotient were not affected by the supplementation with the apple extract. Although body weight was not affected by the treatment, the mice supplemented with the apple extract showed less signs of cachexia than the non-treated mice. In the intestine, the mice supplemented with the apple extract showed lower sucrase, dipeptidyl-peptidase IV, and aminopeptidase N activities, and less intestinal lesions (aberrant crypt foci and polyps). Administration of a polyphenol-rich apple extract reduces the number of neoplastic lesions in mice with AOM-induced colorectal cancer and contributes to preserve adipose tissue mass.

Purpurin binding interacts with LHPP protein that inhibits PI3K/AKT phosphorylation and induces apoptosis in colon cancer cells HCT-116

Colorectal cancer (CRC) is the leading type of diagnosed cancer; globally, it resides in the fourth-leading origin of cancer-interrelated mortality in the globe. The treatment strategies were chemotherapy and potent radiotherapy. Although chemotherapy treatment can eliminate tumor cells, it remains with unnecessary toxic effects in cancer patients. Therefore, the identification of natural-based compounds, which have selectively inhibiting target proteins with limited toxicity that can facilitate the therapeutic approaches against CRC. In this existing approach, which highlights the binding efficacy of our anthraquinone compound, purpurin against phospholysine phosphohistidine inorganic pyrophosphate phosphatase (LHPP) protein restrains the CRC cell growth by inhibiting phosphatidylinositol-3-kinase/protein kinase B (PI3K/AKT), cell proliferation, and inducing apoptosis signaling. Primarily, purpurin (36 μM) exposed to HCT-116 cells and incubated for 24 and 48 h could induce reactive oxygen species production, subsequently alter mitochondrion membrane, and increase the apoptotic cells in HCT-116. LHPP, a kind of histidine phosphatase protein, has been considered as a tumor suppressor in numerous carcinomas. However, purpurin-mediated LHPP proteins and its associated molecular events in CRC remain unclear. In our docking studies revealed that purpurin has been strongly interacts with LHPP via hydrophobic and hydrophilic binding interaction. Western blot results confirmed that purpurin enhances the expression of LHPP protein, thereby inhibits the expression of phosphorylated-PI3K/AKT, EGFR, cyclin-D1, PCNA in HCT-116 cells. Moreover, purpurin induces messenger RNA expression of apoptotic genes (Bax, CASP-9, and CASP-3) in HCT-116 cells. Thus, we conclude that purpurin could be a natural and useful compound, which inhibits the growth of CRC cells through the activation of LHPP proteins.

Lp-PLA2, a potential protector of lung cancer patients complicated with pleural effusion from lung diseases, proves effective for the diagnosis and pathological classification of lung cancer

Abnormal lipid metabolism plays a crucial role in cancers, but few studies have investigated the relationship between lipoprotein-associated phospholipase A2 (Lp-PLA2) and lung cancer. In this study, 58 benign lung disease (LB) and 57 lung cancer (LC) patients complicated with pleural effusion (PE) were included, and their fasting serum and PE samples were collected. Results showed that serum Lp-PLA2 in the LC group was lower than that in the LB group, and other serum lipids were higher (P < 0.05). Tumor markers from serum and the PE samples of LC patients were higher than those in the LB group (P < 0.05). Serum prealbumin (PA) in LC patients was higher than that in the LB group, and serum C-reactive protein (CRP) and procalcitonin (PCT) were lower (P < 0.05). In the LC group, serum Lp-PLA2 concentration was positively correlated with serum triglyceride (TG), Lp (a), carbohydrate antigen 199 (CA199), nutritional markers, and Lp-PLA2 in PE and negatively correlated with serum high-density lipoprotein cholesterol (HDLC), Apolipoprotein A1 (APOA1), CRP, PCT, and alpha fetoprotein (AFP) and LDH in PE. The ROC curve showed that the cutoff level of serum Lp-PLA2 for diagnosing LC was 226.685 (U/L) (sensitivity: 0.632, specificity: 0.793), while the C-index of the nomogram model combined with serum Lp-PLA2, age, and gender was 0.750. In LC patients, the higher serum Lp-PLA2 indicated higher probability of adenocarcinoma and lower probability of squamous cell carcinoma (SCC). In conclusion, Lp-PLA2 may be a protective factor of lung cancer among lung disease patients complicated with pleural effusion, and it would facilitate the diagnosis and pathological classification of lung cancer.

Evaluation of Antineoplasic Activity of Zingiber Officinale Essential Oil in the Colorectal Region of Wistar Rats

INTRODUCTION

Aberrant Crypt (AC) and Aberrant Crypt Focus (ACF) are considered pre-neoplasic lesions, ranging from hyperplasia to different degrees of dysplasia in the colon. This work aimed to evaluate and quantify the chemopreventive activity of Zingiber officinale essential oil in the colorectal region of Wistar rats.

MATERIALS AND METHODS

We extracted the essential oil from ginger rhizomes and carried out ACF induction, in rats, with 1.2 Dimethylhydrazine (DMH) at a 20 mg/kg dose. The experimental groups were GI (negative control); GII (positive induction control); GIII (DMH + essential oil); GIV (DMH +5-Florouracil) and GV (essential oil). The histological techniques used were methylene blue, hematoxylin-eosin (HE) dyeing, and immunohistochemistry (IHQ).

RESULTS

The major essential oil compounds were citral (17.25%), δ-citral (10.25%), camphene (9.55%), α-zingiberene (7.57%), nerol (6.37%) and plelandrene (6.83%). For the presence of AC or ACF, we did not observe them in GI and GV, while in GII and GIII, they were observed, in high values, in both regions, but only in the distal region, there was a significant difference between them. For GIV, for both regions, there were significant lower numbers of AC when compared to GIII. As observed, with HE, there were hyperplastic and dysplastic ACF in the proximal and distal portions of the colon. For IHQ analyses, there were positively PCNA antibody marked cells in all experimental groups. Yet, there was no significant correlation of mitotic index among them. Moreover, the results of GIII compared to GIV were very similar.

CONCLUSION

In this sense, the Zingiber officinale essential oil has good antioxidant potential because it presents a mixture of monoterpene and sesquiterpene compounds. Thus, it is able to develop a chemoprotective effect, as it presented similar results to the standard drug, showing cell proliferation control.

Randomized Study Design to Test Effects of Vitamin D and Omega-3 Fatty Acid Supplementation as Adjuvant Therapy in Colorectal Cancer Patients

This study examines the effects of vitamin D and omega-3 fatty acid co-supplementation on inflammation and nutritional status in colorectal cancer patients. Patients were randomly assigned into four groups: (1) controls, receiving placebos; (2) omega-3 fatty acid arm, receiving two 330 mg omega-3 fatty acid capsules daily and placebo (for vitamin D₃) weekly; (3) vitamin D arm, receiving a 50,000 IU vitamin D₃ soft gel weekly and two placebos (for omega-3 fatty acids) daily; and (4) co-supplementation arm, receiving a 50,000 IU vitamin D₃ soft gel weekly and two 330 mg omega-3 fatty acids capsules daily for 8 weeks. As outcomes, we measure height; weight; fat-free mass (FFM); serum levels of 25(OH)D, TNF-α, and IL-6; C-CRP; and albumin, before and after the intervention. The presented results show that vitamin D₃ plus omega-3 fatty acid co-supplementation in colorectal cancer patients has beneficial impacts on inflammation and nutritional status.

Effect of Heat Treatment on the Anticancer Activity of Houttuynia cordata Thunb Aerial Stem Extract in Human Gastric Cancer SGC-7901 Cells

Gastric cancer is one of the most common malignant tumors in the world, and prevention through diet is one of the ways to control. Houttuynia cordata thunb.(HCT) is a plant having medicine and food function, has many biological properties. However, the effect of food style on the anticancer activity of HCT is not clear. So, we investigate the effect of heat treatment on anticancer activity of HCT. HCT extracts (heated aerial stem, heated subterraneous stem, heated leaves defined as HAS, HSS, HL, respectively, and not heated defined as NAS, NSS, NL, respectively) were obtained, and their inhibited activity were detected by alamar blue assay. The cell apoptosis was detected by DAPI staining and flow cytometry analysis. Western blot was performed to test the expression of apoptotic related protein. HCT showed the anticancer activity in four human tumor cell lines. Interestingly, heat treatment could increase the anticancer activity. In SCG-7901 cells, heat treatment increased anticancer activity of AS by 2-14 folds and induced apoptosis through regulating the intrinsic signaling pathways. Intriguingly, the caspase nine specific inhibitor blocked AS-reduced cell viability. Heat treatment increased the anticancer activity of HCT, and can be used as a dietary style for prevention of gastric cancer.

Bakshi H, L. Hakkim F, Haggag YA, M. Al-Batanyeh K, S. Al Zoubi M, Al-Trad B, M. Nasef M, Satija S, Mehta M, Pabreja K, Mishra V, Khan M, Abobaker S, M. Azzouz I, Dureja H, M. Pabari R, Ali K. Dardouri A, Kesharwani P, Gupta G, Dhar Shukla S, Prasher P, B. Charbe N, Negi P, N. Kapoor D, Chellappan DK, Webba da Silva M, Thompson P, Dua K, McCarron P, M. Tambuwala M. Albumin Nano-Encapsulation of Piceatannol Enhances Its Anticancer Potential in Colon Cancer Via Downregulation of Nuclear p65 and HIF-1α

Piceatannol (PIC) is known to have anticancer activity, which has been attributed to its ability to block the proliferation of cancer cells via suppression of the NF-kB signaling pathway. However, its effect on hypoxia-inducible factor (HIF) is not well known in cancer. In this study, PIC was loaded into bovine serum albumin (BSA) by desolvation method as PIC-BSA nanoparticles (NPs). These PIC-BSA nanoparticles were assessed for in vitro cytotoxicity, migration, invasion, and colony formation studies and levels of p65 and HIF-1α. Our results indicate that PIC-BSA NPs were more effective in downregulating the expression of nuclear p65 and HIF-1α in colon cancer cells as compared to free PIC. We also observed a significant reduction in inflammation induced by chemical colitis in mice by PIC-BSA NPs. Furthermore, a significant reduction in tumor size and number of colon tumors was also observed in the murine model of colitis-associated colorectal cancer, when treated with PIC-BSA NPs as compared to free PIC. The overall results indicate that PIC, when formulated as PIC-BSA NPs, enhances its therpautice potential. Our work could prompt further research in using natural anticancer agents as nanoparticels with possiable human clinical trails. This could lead to the development of a new line of safe and effective therapeutics for cancer patients.

Effects of vitamin D and omega-3 fatty acids co-supplementation on inflammatory biomarkers, tumor marker CEA, and nutritional status in patients with colorectal cancer: a study protocol for a double blind randomized controlled trial

BACKGROUND

Much evidence is available demonstrating that both vitamin D and omega-3 fatty acids block the development and progression of colonic carcinogenesis. The results of animal studies have shown that the consumption of omega-3 fatty acids can decrease inflammatory biomarkers, enhance the efficacy of chemotherapy, and decrease the side effects of chemotherapy or cancer. Also, observational studies propose that higher levels of 25(OH)D are related to improved survival of colorectal cancer patients. This study will aim to evaluate the effects of vitamin D and omega-3 fatty acids co-supplementation on inflammatory biomarkers, tumor marker CEA, and nutritional status in colorectal cancer patients.

METHODS/DESIGN

We will carry out an 8-week double-blind randomized, placebo-controlled clinical trial to evaluate the effects of vitamin D and omega-3 fatty acids co-supplementation on inflammatory biomarkers, tumor marker CEA, and nutritional status in patients with stage ӀӀ or ӀӀӀ colorectal cancer undergoing chemotherapy.

DISCUSSION

Because of the important effects of vitamin D and omega-3 fatty acids on molecular pathways involved in cancer development and progression, it seems that both vitamin D and omega-3 fatty acids may provide a new adjuvant therapy by decreasing inflammatory biomarkers and resistance to cancer treatment in patients with colorectal cancer.

TRIAL REGISTRATION

Iranian Registry of Clinical Trials IRCT20180306038979N1. Registered on 16 March 2018.

Pterostilbene Inhibits Adipocyte Conditioned-Medium-Induced Colorectal Cancer Cell Migration through Targeting FABP5-Related Signaling Pathway

Pterostilbene (PTS) is a phenolic compound with diverse pharmacologic activities. However, its potential for inhibiting obesity-related colorectal cancer (CRC) remains unclear. Our study evaluated the mechanism of inhibitory effects of PTS on adipocyte conditioned-medium (aCM)-induced malignant transformation in HT-29 colorectal adenocarcinoma cells. The results demonstrated that PTS could downregulate the expression of aCM-induced fatty acid-binding protein 5 (FABP5) and prometastatic factors such as vascular endothelial growth factor, matrix metalloproteinase-2 (MMP2), MMP9, and extracellular tumor necrosis factor α via inhibiting aCM-induced nuclear factor-kappa B (NF-κB), β-catenin, and peroxisome proliferator-activated receptor γ (PPAR-γ). Moreover, PTS can suppress aCM-stimulated phosphoinositide 3-kinase (PI3K), protein kinase B (Akt), p38 mitogen-activated protein kinase (p38 MAPK), extracellular signal-regulated kinase (ERK), and c-Jun N-terminal kinases 1/2 (JNK 1/2) signaling pathways activation that are upstream of NF-κB, β-catenin, and PPAR-γ. Therefore, we suggest that PTS could alleviate adiposity-induced metastasis in CRC via inhibiting cell migration through downregulating FABP5 gene expression.

Effect of Juice and Extracts from Saposhnikovia divaricata Root on the Colon Cancer Cells Caco-2

Colorectal cancer ranks 3rd in terms of cancer incidence. Growth and development of colon cancer cells may be affected by juice and extracts from Saposhnikovia divaricata root. The objective of the research was to analyze the effect of S. divaricata juice and extracts on the viability, membrane integrity and types of cell death of Caco-2 cells. Juice and extracts were analyzed using Ultra-High Performance Liquid Chromatography-Mass Spectrometry (UHPLC-MS) and in respect of the presence of antioxidants, total carbohydrates, protein, fat and polyphenols. The contents of cimifugin β-D-glucopyranoside, cimifugin, 4′-O-glucopyranosyl-5-O-methylvisamminol, imperatorin and protein were the highest in juice. 50% Hydroethanolic extract had the greatest antioxidant potential, concentration of polyphenols and fat. Water extract was characterized by the highest content of glutathione. Juice and 75% hydroethanolic extract contained the most carbohydrates. After the application of juice, 50% extract and the juice fraction containing the molecules with molecular weights >50 kDa, a decrease of the cell viability was noted. Juice and this extract exhibited the protective properties in relation to the cell membranes and they induced apoptosis. The knowledge of further mechanisms of anticancer activity of the examined products will allow to consider their use as part of combination therapy.

Djulis (Chenopodium Formosanum) Prevents Colon Carcinogenesis via Regulating Antioxidative and Apoptotic Pathways in Rats

Djulis is a cereal crop rich in polyphenols and dietary fiber that may have nutraceutical activity to prevent colon cancer. This study was designed to examine the preventive effect of djulis on colon carcinogenesis in rats treated with 1,2-dimethylhydrazine (DMH). Rats were fed different AIN-93G-based diets: groups N and DMH were fed AIN-93G diet and groups LD, MD, and HD were fed AIN-93G diet containing 5, 10, and 20% djulis, respectively. All rats except for group N were injected with DMH to induce colon carcinogenesis. After 10 weeks, rats were sacrificed and colon and liver tissues were collected for analysis. The results showed that djulis-treated rats had significantly lower numbers of colonic preneoplastic lesions, aberrant crypt foci (ACF), sialomucin-producing (SIM)-ACF, and mucin-depleted foci. Djulis treatment increased superoxide dismutase and catalase activities in colon and liver. Djulis also reduced p53, Bcl-2, and proliferating cell nuclear antigen expressions and increased Bax and caspase-9 expressions. Besides, phenolic compounds and flavonoids were found rich in djulis. These results demonstrate the chemopreventive effect of djulis on carcinogen-induced colon carcinogenesis via regulating antioxidative and apoptotic pathways in rats. Djulis may have the potential to be developed as a valuable cereal product for chemoprevention of colon cancer.

Effects of Vitamin D and Omega-3 Fatty Acids Co-Supplementation on Inflammatory Factors and Tumor Marker CEA in Colorectal Cancer Patients Undergoing Chemotherapy: A Randomized, Double-Blind, Placebo-Controlled Clinical Trial

Objectives: This study aimed to investigate the effects of vitamin D and omega-3 fatty acids co-supplementation on inflammatory factors and tumor marker CEA in colorectal cancer patients undergoing chemotherapy.Methods: In this study, 81 patients with stage ӀӀ or ӀӀӀ colorectal cancer were randomly assigned into four groups: (1) control: receiving a vitamin D placebo, weekly + two omega-3 fatty acid placebo capsules, daily; (2) omega-3 fatty acid, receiving two omega-3 fatty acid capsules (each capsule containing 330 mg of omega-3 fatty acids), daily + a vitamin D placebo, weekly; (3) vitamin D, receiving a 50,000 IU vitamin D soft gel, weekly + two omega-3 fatty acid placebo capsules, daily; (4) co-supplementation, receiving a 50,000 IU vitamin D soft gel, weekly + two omega-3 fatty acids capsules, for 8 weeks. Before and after the intervention, serum levels of 25(OH)D, TNF-α, IL-1β, IL-6, IL-8, NF-kB activity, and tumor marker CEA, were measured.Results: After 8 weeks of intervention, patients who received combined vitamin D and omega-3 fatty acids supplements compared with omega-3, vitamin D, and placebo had significantly decreased TNF-α, and IL-1β (P < .05). In addition, serum levels of TNF-α, IL-1β, IL-6, IL-8, and tumor marker CEA were decreased significantly in omega-3, vitamin D, and co-supplementation of them, compared with baseline. NF-kB activity was decreased significantly in vitamin D and co-supplementation groups, compared with baseline. Regarding CEA, there was no significant difference between the four groups at the end of intervention (P > .05).Conclusion: Results show that co-supplementation of vitamin D and omega-3 fatty acids co-supplementation, in colorectal cancer patients have beneficial impacts on inflammation and tumor marker CEA.

Synergy between dihydromyricetin intervention and irinotecan chemotherapy delays the progression of colon cancer in mouse models

Colorectal cancer (CRC) is the third highest cause of cancer-related death and the main option for prolonged survival is chemotherapeutic intervention. There is increasing interest in dietary intervention using natural agents to enhance the sensitivity of such invasive chemical treatment. In this study, the chemotherapeutic efficacy of dihydromyricetin (DMY) intervention on treatments involving irinotecan (CPT-11) or gemcitabine (GM) was evaluated in an AOM/DSS-induced colitis-associated colon cancer model and a Min (Apc Min/+) mice model. Our data showed that DMY could promote the CPT-11 effect both in the mouse model of AOM/DSS and Apc Min/+ cancer and had no influence on the GM effect. In AOM/DSS cancer, tumors were sensitive to 100 mg kg-1 DMY chemotherapy under 100 mg kg-1 or 200 mg kg-1 CPT-11. DMY-driven CPT-11 chemotherapy induced enhanced IgG levels and the reduction of Fusobacterium abundance in the gut. In the Min model, CPT-11 with 20 mg kg-1 DMY prevented tumor formation but not with 100 mg kg-1 DMY. Mechanically, chloride ion-dependent CFTR, CLCN4, and CLIC4 signaling are not involved in DMY mediated chemotherapeutic colon tumorigenesis. These results suggested that a suitable dose of DMY could act as a coadjuvant to CPT-11 chemotherapy.

Preventive Effect of an Infusion of the Aqueous Extract of Chaya Leaves (Cnidoscolus aconitifolius) in an Aberrant Crypt Foci Rat Model Induced by Azoxymethane and Dextran Sulfate Sodium

Aberrant crypt foci (ACF) is the precursor lesion of colorectal carcinogenesis (CRC), one of the most common malignancies in the world. Many studies have reported that people with higher phytochemical intake are at a reduced risk of developing ACF. One example of the botanical potential of preventive plant products is Cnidoscolus aconitifolius (CA), commonly known as Chaya. This study evaluated the phenolic profile of CA and the effects of the daily consumption of CA leaf infusion on the formation of ACF, histopathological lesions, and molecular biomarkers after azoxymethane (AOM) and dextran sulfate sodium (DSS) induced premalignant colon lesions in rats treated with for 16 and 32 weeks. The phenolic composition of the CA infusion was identified by reversed phase-high performance liquid chromatography-diode array detection (RP-HPCC-DAD). After sacrifice, a 4 cm segment was collected from the distal part of the colon and stained with methylene blue to look for ACF. Furthermore, 4 μm of colon, liver, and kidney was collected and stained with hematoxylin and eosin for histopathological analysis, along with 7 μm of colon for immunohistochemistry analysis. Eleven phenolic compounds were identified in the infusions, and ACF formation was reduced by 29.5% at the subchronic and by 64.6% at chronic stages. Lesions on kidney, liver, and colon tissue were also reduced. Our data suggest that CA treatment has preventive effects against AOM-/DSS-induced premalignant colon lesions in colon rats at the promotion level, inhibiting the cell proliferation of early neoplastic lesions and colonic inflammation through the decrease of β-catenin by 41.8% at the subchronic stage and 29% at the chronic stage, along with a 46.2% reduction of cyclooxygenase 2 (COX-2) at long term, despite a high expression of NF-κB (30.3% at the subchronic stage and 22.8% at the chronic stage).

Fruit and vegetable consumption and health outcomes: an umbrella review of observational studies

The aim of this study was to provide a comprehensive evaluation of current evidence on fruit and vegetable consumption and health outcomes. A systematic search for quantitative syntheses was performed. Several criteria, including study design, dose-response relationship, heterogeneity and agreement of results over time, and identification of potential confounding factors, were used to assess the level of evidence. The strongest (probable) evidence was found for cardiovascular disease protection; possible evidence for decreased risk of colon cancer, depression and pancreatic diseases was found for fruit intake; and colon and rectal cancer, hip fracture, stroke, depression and pancreatic diseases was found for vegetable intake. Suggestive and rather limited associations with other outcomes have been found. Evidence of potential confounding by sex and geographical localisation has been reported. Despite findings are consistent enough for hypothesising causation (at least for cardiovascular-related outcomes), further studies are needed to clarify the role of potential confounding factors.

The inhibitory effect of Filipendula ulmaria (L.) Maxim. on colorectal carcinogenesis induced in rats by methylnitrosourea

ETHNOPHARMACOLOGICAL RELEVANCE

Meadowsweet (Filipendula ulmaria (L.) Maxim.) is a medicinal plant with a variety of therapeutic properties, traditionally used in various diseases including treatment and prevention of tumors. The aim of this study was to present an ethnomedicinal justification that a meadowsweet decoction is able to inhibit colorectal carcinogenesis induced by the methylnitrosourea (MNU) in rats.

MATERIALS AND METHODS

The chemical composition of meadowsweet extracts was studied by traditional methods. In animal experiments adult outbred female rats received four intrarectal instillations of MNU, one per week, at dose 4 mg in 0.5 ml saline (the total dose of MNU during the 4-week exposure was 16 mg/rat). After carcinogenic exposure one group (MNU) of rats continued to receive standard feed and tap water throughout life. In another group (MNU+meadowsweet), rats were given daily a decoction of the meadowsweet instead of drinking water and standard feed.

RESULTS

Meadowsweet extracts showed a sufficiently high content of flavonoids and tannins and also some individual phenolic compounds and salicylic acid. In rats after administration of MNU the overall incidence of tumors was 91% with tumor multiplicity of 3.5. The majority of rats (86%) developed multiple tumors of large intestine (most often adenocarcinomas:88 from 107; index of multiplicity - 2.0). In rats from the group MNU+meadowsweet there was a statistically significant decrease of the overall tumor incidence and multiplicity-by 1.4 and 2.9 times, respectively, and the incidence and multiplicity of colon tumors - by 2.0 and 2.8 times, respectively; the incidence and multiplicity of malignant tumors of other localizations was also reduced-by 2.2 and 3.0 times, respectively.

CONCLUSIONS

Meadowsweet extract is an effective inhibitor of colorectal carcinogenesis in experiment, that provides support for the traditional use of this plant in the oncology.

Chemoprevention of Colorectal Cancer by Dietary Compounds

Colorectal cancer is one of the leading causes of death, and the third most diagnosed type of cancer, worldwide. It is most common amongst men and women over 50 years old. Risk factors include smoking, alcohol, diet, physical inactivity, genetics, alterations in gut microbiota, and associated pathologies (diabetes, obesity, chronic inflammatory bowel diseases). This review will discuss, in detail, the chemopreventive properties of some dietary compounds (phenolic compounds, carotenoids, iridoids, nitrogen compounds, organosulfur compounds, phytosterols, essential oil compounds, polyunsaturated fatty acids and dietary fiber) against colorectal cancer. We present recent data, focusing on in vitro, laboratory animals and clinical trials with the previously mentioned compounds. The chemopreventive properties of the dietary compounds involve multiple molecular and biochemical mechanisms of action, such as inhibition of cell growth, inhibition of tumor initiation, inhibition of adhesion, migration and angiogenesis, apoptosis, interaction with gut microbiota, regulation of cellular signal transduction pathways and xenobiotic metabolizing enzymes, etc. Moreover, this review will also focus on the natural dietary compounds' bioavailability, their synergistic protective effect, as well as the association with conventional therapy. Dietary natural compounds play a major role in colorectal chemoprevention and continuous research in this field is needed.

Opinion on the Hurdles and Potential Health Benefits in Value-Added Use of Plant Food Processing By-Products as Sources of Phenolic Compounds

Plant foods, their products and processing by-products are well recognized as important sources of phenolic compounds. Recent studies in this field have demonstrated that food processing by-products are often richer sources of bioactive compounds as compared with their original feedstock. However, their final application as a source of nutraceuticals and bioactives requires addressing certain hurdles and challenges. This review discusses recent knowledge advances in the use of plant food processing by-products as sources of phenolic compounds with special attention to the role of genetics on the distribution and biosynthesis of plant phenolics, as well as their profiling and screening, potential health benefits, and safety issues. The potentialities in health improvement from food phenolics in animal models and in humans is well substantiated, however, considering the emerging market of plant food by-products as potential sources of phenolic bioactives, more research in humans is deemed necessary.

A prospective evaluation of plasma polyphenol levels and colon cancer risk

Polyphenols have been shown to exert biological activity in experimental models of colon cancer; however, human data linking specific polyphenols to colon cancer is limited. We assessed the relationship between pre-diagnostic plasma polyphenols and colon cancer risk in a case-control study nested within the European Prospective Investigation into Cancer and Nutrition study. Using high pressure liquid chromatography coupled to tandem mass spectrometry, we measured concentrations of 35 polyphenols in plasma from 809 incident colon cancer cases and 809 matched controls. We used multivariable adjusted conditional logistic regression models that included established colon cancer risk factors. The false discovery rate (qvalues ) was computed to control for multiple comparisons. All statistical tests were two-sided. After false discovery rate correction and in continuous log2 -transformed multivariable models, equol (odds ratio [OR] per log2 -value, 0.86, 95% confidence interval [95% CI] = 0.79-0.93; qvalue  = 0.01) and homovanillic acid (OR per log2 -value, 1.46, 95% CI = 1.16-1.84; qvalue  = 0.02) were associated with colon cancer risk. Comparing extreme fifths, equol concentrations were inversely associated with colon cancer risk (OR = 0.61, 95% CI = 0.41-0.91, ptrend  = 0.003), while homovanillic acid concentrations were positively associated with colon cancer development (OR = 1.72, 95% CI = 1.17-2.53, ptrend  < 0.0001). No heterogeneity for these associations was observed by sex and across other colon cancer risk factors. The remaining polyphenols were not associated with colon cancer risk. Higher equol concentrations were associated with lower risk, and higher homovanillic acid concentrations were associated with greater risk of colon cancer. These findings support a potential role for specific polyphenols in colon tumorigenesis.

Colon targeted beads loaded with pterostilbene: Formulation, optimization, characterization and in vivo evaluation

Background

Pterostilbene has a proven chemopreventive effect for colon carcinogenesis but suffers low bioavailability limitations and therefore unable to reach the colonic tissue.

Objective and methodology

To overcome the issue of low bioavailability, pterostilbene was formulated into an oral colon targeted beads by ionic gelation method using pectin and zinc acetate. Optimization was carried out by 2³ factorial design whereby the effect of pectin concentration (X₁), zinc acetate concentration (X₂) and pterostilbene:pectin ratio (X₃) were studied on entrapment efficiency (Y₁) and in vitro drug release till 24 h (Y₂). The optimized beads were characterized for shape and size, swelling and surface morphology. The optimized beads were uniformly coated with Eudragit S-100 using fluidized bed coater. Optimized coated beads were characterized for in vitro drug release till 24 h and surface morphology. Pharmacokinetic and organ distribution study were performed in rats to ascertain the release of pterostilbene in colon.

Results

The optimized formulation comprised of 2% w/v of pectin concentration (X₁), 2% w/v of zinc acetate concentration (X₂) and 1:4 of pterostilbene:pectin ratio (X₃), which showed a satisfactory entrapment efficiency (64.80%) and in vitro release (37.88%) till 24 h. The zinc pectinate beads exhibited sphericity, uniform size distribution, adequate swelling and rough surface. The optimized coated beads achieved 15% weight gain, displayed smooth surface and optimum drug release. Pterostilbene from optimized coated beads appeared in the plasma at 14 h and reached the C_max at 22 h (T_max), whereas plain pterostilbene exhibited T_max of 3 h.

Discussion and conclusion

Thus, larger distribution of pterostilbene was obtained in the colonic tissue compared to stomach and small intestinal tissues. Thus, delayed T_max and larger distribution of pterostilbene in colonic tissue confirmed the targeting of beads to colon.