Resveratrol Chemosensitizes TNF-β-Induced Survival of 5-FU-Treated Colorectal Cancer Cells

Association between inflammatory factors and melanoma: a bidirectional Mendelian randomization study

PURPOSE

This study performed a bidirectional Mendelian randomization (MR) analysis to elucidate the causal relationships of C-reactive protein and 41 inflammatory regulators with melanoma, including data from UK Biobank, Cardiovascular Risk in Young Finns Study, and Cohorts for Inflammation Work Group.

METHODS

We selected the inverse variance weighting (IVW) to merge the estimated causal effects of multiple SNPs into a weighted average. To evaluate the heterogeneities of IVW, the Cochran Q statistic, and I2 index were used. What's more, several sensitivity analyses were employed, including IVW, MR-Egger, weighted median, and Mendelian Randomization Pleiotropy RESidual Sum and Outlier (MR-PRESSO).

RESULTS

With SNPs reaching P < 5 × 10-8, the analyses findings revealed that IL-16 had a significant positively association with genetically risk of melanoma (ORIVW: 1.05; 95% CI: 1.03-1.07; P < 0.001), and high levels of MCP1 (ORIVW: 1.13; 95% CI: 1.03-1.23; P = 0.01) were suggestively associated with melanoma susceptibility. What's more, TNF-β (ORIVW: 1.07; 95% CI: 1.01-1.13; P = 0.02) and IL-8 (ORIVW: 1.08, 95% CI: 1.01-1.16; P = 0.03) were demonstrated a positive association with the risk of melanoma under a less stringent cut-off (P < 5 × 10-6). Conversely, we found a facilitative effect of melanoma susceptibility on IP-10 and inhibitory effects on IL-6, IL-1b, and GRO-α.

CONCLUSION

The genetic evidence that we have uncovered indicates a potential association between the levels of specific inflammatory markers (IL-16, IL-8, MCP-1, and TNF-β) and the risk of melanoma. Further research is imperative to translate these findings into clinical applications.

A mechanistic insight into the anticancer potentials of resveratrol: Current perspectives

Resveratrol is a widely recognized polyphenolic phytochemical found in various plants and their fruits, such as peanuts, grapes, and berry fruits. It is renowned for its several health advantages. The phytochemical is well known for its anticancer properties, and a substantial amount of clinical evidence has also established its promise as a chemotherapeutic agent. This study focuses on assessing the anticancer properties of resveratrol and gaining insight into the underlying molecular mechanisms. It also evaluates the biopharmaceutical, toxicological characteristics, and clinical utilization of resveratrol to determine its suitability for further development as a reliable anticancer agent. Therefore, the information about preclinical and clinical studies was collected from different electronic databases up-to-date (2018-2023). Findings from this study revealed that resveratrol has potent therapeutic benefits against various cancers involving different molecular mechanisms, such as induction of oxidative stress, cytotoxicity, inhibition of cell migration and invasion, autophagy, arresting of the S phase of the cell cycle, apoptotic, anti-angiogenic, and antiproliferative effects by regulating different molecular pathways including PI3K/AKT, p38/MAPK/ERK, NGFR-AMPK-mTOR, and so on. However, the compound has poor oral bioavailability due to reduced absorption; this limitation is overcome by applying nanotechnology (nanoformulation of resveratrol). Clinical application also showed therapeutic benefits in several types of cancer with no serious adverse effects. We suggest additional extensive studies to further check the efficacy, safety, and long-term hazards. This could involve a larger number of clinical samples to establish the compound as a reliable drug in the treatment of cancer.

Natural products reverse cancer multidrug resistance

Cancer stands as a prominent global cause of death. One of the key reasons why clinical tumor chemotherapy fails is multidrug resistance (MDR). In recent decades, accumulated studies have shown how Natural Product-Derived Compounds can reverse tumor MDR. Discovering novel potential modulators to reduce tumor MDR by Natural Product-Derived Compounds has become a popular research area across the globe. Numerous studies mainly focus on natural products including flavonoids, alkaloids, terpenoids, polyphenols and coumarins for their MDR modulatory activity. Natural products reverse MDR by regulating signaling pathways or the relevant expressed protein or gene. Here we perform a deep review of the previous achievements, recent advances in the development of natural products as a treatment for MDR. This review aims to provide some insights for the study of multidrug resistance of natural products.

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.

The Combination of 5-FU and Resveratrol Can Suppress the Growth of Glioblastoma Cells Through Downregulation of TRPM2 and β-Catenin

Glioblastoma multiforme (GBM) is the most common as well as the most fatal primary malignant tumor of the central nervous system (CNS), which still lacks a definitive cure. 5-FU is an anti-metabolite anti-cancer agent which has shown promising results for GBM treatment. Resveratrol (Res) is a phytochemical anti-oxidant that has also been effective in suppressing the progression of GBM. The combination of 5-FU and Res has been studied in a variety of cancers, but no study has assessed this combination in GBM. In this study, we investigated how 5-FU and Res, in combination and alone, may affect the growth and apoptosis of GBM cells and also the potential of TRPM2 and β-catenin as the mediator of their effects. U87 cells were cultured as the in vitro model. MTT assay was used for measuring cellular growth, and RT-qPCR was used to measure the level of caspase-3, TRPM2, and β-catenin; caspase-3 level served as the indicator of apoptotic rate. 5-FU and Res, in combination and alone, suppressed the growth while promoting the apoptosis of U87 cells; these effects were significantly greater when they were used in combination. RT-qPCR showed downregulation of TRPM-2 and β-catenin in response to this combination, which suggested that these two molecules may mediate the cited anti-oncogenic effects. In conclusion, our study confirmed the synergism between 5-FU and Res in suppressing the progression of GBM and suggested the putative axis of TRPM2/ β-catenin as the downstream mediator of this therapeutic regime. Future studies may be able to approve the eligibility of this therapeutic regime for GBM treatment and also the underlying mechanism.

Resveratrol and p53: How are they involved in CRC plasticity and apoptosis?

BACKGROUND

Colorectal cancer (CRC), which is mainly caused by epigenetic and lifestyle factors, is very often associated with functional plasticity during its development. In addition, the malignant plasticity of CRC cells underscores one of their survival abilities to functionally adapt to specific stresses, including inflammation, that occur during carcinogenesis. This leads to the generation of various subsets of cancer cells with phenotypic diversity and promotes epithelial-mesenchymal transition (EMT), formation of cancer cell stem cells (CSCs) and metabolic reprogramming. This can enhance cancer cell differentiation and facilitate tumorigenic potential, drug resistance and metastasis.

AIM OF REVIEW

The tumor protein p53 acts as one of the central suppressors of carcinogenesis by regulating its target genes, whose proteins are involved in the plasticity of cancer cells, autophagy, cell cycle, apoptosis, DNA repair. The aim of this review is to summarize the latest published research on resveratrol's effect in the prevention of CRC, its regulatory actions, specifically on the p53 pathway, and its treatment options.

KEY SCIENTIFIC CONCEPTS OF REVIEW

Resveratrol, a naturally occurring polyphenol, is a potent inducer of a variety of tumor-controlling. However, the underlying mechanisms linking the p53 signaling pathway to the functional anti-plasticity effect of resveratrol in CRC are still poorly understood. Therefore, this review discusses novel relationships between anti-cellular plasticity/heterogeneity, pro-apoptosis and modulation of tumor protein p53 signaling in CRC oncogenesis, as one of the crucial mechanisms by which resveratrol prevents malignant phenotypic changes leading to cell migration and drug resistance, thus improving the ongoing treatment of CRC.

Functional Roles of CD133: More than Stemness Associated Factor Regulated by the Microenvironment

CD133 protein has been one of the most used surface markers to select and identify cancer cells with stem-like features. However, its expression is not restricted to tumoral cells; it is also expressed in differentiated cells and stem/progenitor cells in various normal tissues. CD133 participates in several cellular processes, in part orchestrating signal transduction of essential pathways that frequently are dysregulated in cancer, such as PI3K/Akt signaling and the Wnt/β-catenin pathway. CD133 expression correlates with enhanced cell self-renewal, migration, invasion, and survival under stress conditions in cancer. Aside from the intrinsic cell mechanisms that regulate CD133 expression in each cellular type, extrinsic factors from the surrounding niche can also impact CD33 levels. The enhanced CD133 expression in cells can confer adaptive advantages by amplifying the activation of a specific signaling pathway in a context-dependent manner. In this review, we do not only describe the CD133 physiological functions known so far, but importantly, we analyze how the microenvironment changes impact the regulation of CD133 functions emphasizing its value as a marker of cell adaptability beyond a cancer-stem cell marker.

CD24hiCD27+ Bregs within Metastatic Lymph Nodes Promote Multidrug Resistance in Breast Cancer

PURPOSE

Axillary lymph nodes (LN) are the primary and dominant metastatic sites in breast cancer. However, the interaction between tumor cells and immune cells within metastatic LNs (mLN) remains poorly understood. In our study, we explored the effect of CD24hiCD27+ regulatory B cells (Breg) within mLNs on orchestrating drug resistance of breast cancer cells.

EXPERIMENTAL DESIGN

We collected mLN samples from patients with breast cancer who had received standard neoadjuvant therapy (NAT) and analyzed the spatial features of CD24hiCD27+ Bregs through multicolor immunofluorescence staining. The effect of CD24hiCD27+ Bregs on drug resistance of breast cancer cells was evaluated via in vitro experiments. A mouse model with mLNs was used to evaluate the strategies with blocking the interactions between Bregs and breast cancer for improving tumor regression within mLNs.

RESULTS

In patients with breast cancer who had received NAT, there is a close spatial correlation between activated CD24hiCD27+ Bregs and residual tumor cells within mLNs. Mechanistically, CD24hiCD27+ Bregs greatly enhance the acquisition of multidrug resistance and stem-like features of breast cancer cells by secreting IL6 and TNFα. More importantly, breast cancer cells further promote the activation of CD24hiCD27+ Bregs via CD40L-dependent and PD-L1-dependent proximal signals, forming a positive feedback pattern. PD-L1 blockade significantly attenuates the drug resistance of breast cancer cells induced by CD24hiCD27+ Bregs, and addition of anti-PD-L1 antibody to chemotherapy improves tumor cell remission in mLNs.

CONCLUSIONS

Our study reveals the pivotal role of CD24hiCD27+ Bregs in promoting drug resistance by interacting with breast cancer cells in mLNs, providing novel evidence for an improved strategy of chemoimmunotherapy combination for patients with breast cancer with mLNs.

Molecular mechanisms of resveratrol as chemo and radiosensitizer in cancer

One of the primary diseases that cause death worldwide is cancer. Cancer cells can be intrinsically resistant or acquire resistance to therapies and drugs used for cancer treatment through multiple mechanisms of action that favor cell survival and proliferation, becoming one of the leading causes of treatment failure against cancer. A promising strategy to overcome chemoresistance and radioresistance is the co-administration of anticancer agents and natural compounds with anticancer properties, such as the polyphenolic compound resveratrol (RSV). RSV has been reported to be able to sensitize cancer cells to chemotherapeutic agents and radiotherapy, promoting cancer cell death. This review describes the reported molecular mechanisms by which RSV sensitizes tumor cells to radiotherapy and chemotherapy treatment.

TGF-β in correlation with tumor progression, immunosuppression and targeted therapy in colorectal cancer

Colorectal cancer (CRC) is a complex malignancy responsible for the second-highest cancer deaths worldwide. TGF-β maintains normal cellular homeostasis by inhibiting the cell cycle and inducing apoptosis, but its elevated level is correlated with colorectal cancer progression, as TGF-β is a master regulator of the epithelial-to-mesenchymal transition, a critical step of metastasis. Tumors, including CRC, use elevated TGF-β levels to avoid immune surveillance by modulating immune cell differentiation, proliferation, and effector function. Presently, the treatment of advanced CRC is mainly based on chemotherapy, with multiple adverse effects. Thus, there is a need to develop alternate tactics because CRC continue to be mostly resistant to the present therapeutic regimen. TGF-β blockade has emerged as a promising therapeutic target in cancer therapy. Blocking TGF-β with phytochemicals and other molecules, such as antisense oligonucleotides, monoclonal antibodies, and bifunctional traps, alone or in combination, may be a safer and more effective way to treat CRC. Furthermore, combination immunotherapy comprising TGF-β blockers and immune checkpoint inhibitors is gaining popularity because both molecules work synergistically to suppress the immune system. Here, we summarize the current understanding of TGF-β as a therapeutic target for managing CRC and its context-dependent tumor-promoting or tumor-suppressing nature.

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.

Combination Chemotherapy with Selected Polyphenols in Preclinical and Clinical Studies-An Update Overview

This review article describes studies published over the past five years on the combination of polyphenols, which are the most studied in the field of anticancer effects (curcumin, quercetin, resveratrol, epigallocatechin gallate, and apigenin) and chemotherapeutics such as cisplatin, 5-fluorouracil, oxaliplatin, paclitaxel, etc. According to WHO data, research has been limited to five cancers with the highest morbidity rate (lung, colorectal, liver, gastric, and breast cancer). A systematic review of articles published in the past five years (from January 2018 to January 2023) was carried out with the help of all Web of Science databases and the available base of clinical studies. Based on the preclinical studies presented in this review, polyphenols can enhance drug efficacy and reduce chemoresistance through different molecular mechanisms. Considering the large number of studies, curcumin could be a molecule in future chemotherapy cocktails. One of the main problems in clinical research is related to the limited bioavailability of most polyphenols. The design of a new co-delivery system for drugs and polyphenols is essential for future clinical research. Some polyphenols work in synergy with chemotherapeutic drugs, but some polyphenols can act antagonistically, so caution is always required.

Research progress of traditional Chinese medicine as sensitizer in reversing chemoresistance of colorectal cancer

In recent years, the incidences and mortalities from colorectal cancer (CRC) have been increasing; therefore, there is an urgent need to discover newer drugs that enhance drug sensitivity and reverse drug tolerance in CRC treatment. With this view, the current study focuses on understanding the mechanism of CRC chemoresistance to the drug as well as exploring the potential of different traditional Chinese medicine (TCM) in restoring the sensitivity of CRC to chemotherapeutic drugs. Moreover, the mechanism involved in restoring sensitivity, such as by acting on the target of traditional chemical drugs, assisting drug activation, increasing intracellular accumulation of anticancer drugs, improving tumor microenvironment, relieving immunosuppression, and erasing reversible modification like methylation, have been thoroughly discussed. Furthermore, the effect of TCM along with anticancer drugs in reducing toxicity, increasing efficiency, mediating new ways of cell death, and effectively blocking the drug resistance mechanism has been studied. We aimed to explore the potential of TCM as a sensitizer of anti-CRC drugs for the development of a new natural, less-toxic, and highly effective sensitizer to CRC chemoresistance.

Resveratrol Modulates Chemosensitisation to 5-FU via β1-Integrin/HIF-1α Axis in CRC Tumor Microenvironment

Frequent development of resistance to chemotherapeutic agents such as 5-flourouracil (5-FU) complicates the treatment of advanced colorectal cancer (CRC). Resveratrol is able to utilize β1-integrin receptors, strongly expressed in CRC cells, to transmit and exert anti-carcinogenic signals, but whether it can also utilize these receptors to overcome 5-FU chemoresistance in CRC cells has not yet been investigated. Effects of β1-integrin knockdown on anti-cancer capabilities of resveratrol and 5-FU were investigated in HCT-116 and 5-FU-resistant HCT-116R CRC tumor microenvironment (TME) with 3D-alginate as well as monolayer cultures. Resveratrol increased CRC cell sensitivity to 5-FU by reducing TME-promoted vitality, proliferation, colony formation, invasion tendency and mesenchymal phenotype including pro-migration pseudopodia. Furthermore, resveratrol impaired CRC cells in favor of more effective utilization of 5-FU by down-regulating TME-induced inflammation (NF-kB), vascularisation (VEGF, HIF-1α) and cancer stem cell production (CD44, CD133, ALDH1), while up-regulating apoptosis (caspase-3) that was previously inhibited by TME. These anti-cancer mechanisms of resveratrol were largely abolished by antisense oligonucleotides against β1-integrin (β1-ASO) in both CRC cell lines, indicating the particular importance of β1-integrin receptors for the 5-FU-chemosensitising effect of resveratrol. Lastly, co-immunoprecipitation tests showed that resveratrol targets and modulates the TME-associated β1-integrin/HIF-1α signaling axis in CRC cells. Our results suggest for the first time the utility of the β1-integrin/HIF-1α signaling axis related to chemosensitization and overcoming chemoresistance to 5-FU in CRC cells by resveratrol, underlining its potential supportive applications in CRC treatment.

Targeting cancer stem cells and signalling pathways through phytochemicals: A promising approach against colorectal cancer

BACKGROUND

Cancer stem cells (CSCs) are strongly associated with high tumourigenicity, chemotherapy or radiotherapy resistance, and metastasis and recurrence, particularly in colorectal cancer (CRC). Therefore, targeting CSCs may be a promising approach. Recently, discovery and research on phytochemicals that effectively target colorectal CSCs have been gaining popularity because of their broad safety profile and multi-target and multi-pathway modes of action.

PURPOSE

This review aimed to elucidate and summarise the effects and mechanisms of phytochemicals with potential anti-CSC agents that could contribute to the better management of CRC.

METHODS

We reviewed PubMed, EMBASE, Web of Science, Ovid, ScienceDirect and China National Knowledge Infrastructure databases from the original publication date to March 2022 to review the mechanisms by which phytochemicals inhibit CRC progression by targeting CSCs and their key signalling pathways. Phytochemicals were classified and summarised based on the mechanisms of action.

RESULTS

We observed that phytochemicals could affect the biological properties of colorectal CSCs. Phytochemicals significantly inhibit self-renewal, migration, invasion, colony formation, and chemoresistance and induce apoptosis and differentiation of CSCs by regulating the Wnt/β-catenin pathway (e.g., diallyl trisulfide and genistein), the phosphatidylinositol-3-kinase/protein kinase B/mammalian target of rapamycin pathway (e.g., caffeic acid and piperlongumine), the neurogenic locus notch homolog protein pathway (e.g., honokiol, quercetin, and α-mangostin), the Janus kinase-signal transducer and activator of transcription pathway (e.g., curcumin, morin, and ursolic acid), and other key signalling pathways. It is worth noting that several phytochemicals, such as resveratrol, silibinin, evodiamine, and thymoquinone, highlight multi-target and multi-pathway effects in restraining the malignant biological behaviour of CSCs.

CONCLUSIONS

This review demonstrates the potential of targeted therapies for colorectal CSCs using phytochemicals. Phytochemicals could serve as novel therapeutic agents for CRC and aid in drug development.

The Potential Role of Fisetin, a Flavonoid in Cancer Prevention and Treatment

Cancer is a main culprit and the second-leading cause of death worldwide. The current mode of treatment strategies including surgery with chemotherapy and radiation therapy may be effective, but cancer is still considered a major cause of death. Plant-derived products or their purified bioactive compounds have confirmed health-promoting effects as well as cancer-preventive effects. Among these products, flavonoids belong to polyphenols, chiefly found in fruits, vegetables and in various seeds/flowers. It has been considered to be an effective antioxidant, anti-inflammatory and to play a vital role in diseases management. Besides these activities, flavonoids have been revealed to possess anticancer potential through the modulation of various cell signaling molecules. In this regard, fisetin, a naturally occurring flavonoid, has a confirmed role in disease management through antioxidant, neuro-protective, anti-diabetic, hepato-protective and reno-protective potential. As well, its cancer-preventive effects have been confirmed via modulating various cell signaling pathways including inflammation, apoptosis, angiogenesis, growth factor, transcription factor and other cell signaling pathways. This review presents an overview of the anti-cancer potential of fisetin in different types of cancer through the modulation of cell signaling pathways based on in vivo and in vitro studies. A synergistic effect with anticancer drugs and strategies to improve the bioavailability are described. More clinical trials need to be performed to explore the anti-cancer potential and mechanism-of-action of fisetin and its optimum therapeutic dose.

ALDH1: A potential therapeutic target for cancer stem cells in solid tumors

Solid tumors can be divided into benign solid tumors and solid malignant tumors in the academic community, among which malignant solid tumors are called cancers. Cancer is the second leading cause of death in the world, and the global incidence of cancer is increasing yearly New cancer patients in China are always the first. After the concept of stem cells was introduced in the tumor community, the CSC markers represented by ALDH1 have been widely studied due to their strong CSC cell characteristics and potential to be the driving force of tumor metastasis. In the research results in the past five years, it has been found that ALDH1 is highly expressed in various solid cancers such as breast cancer, lung cancer, colorectal cancer, liver cancer, gastric cancer, cervical cancer, esophageal cancer, ovarian cancer, head,and neck cancer. ALDH1 can activate and transform various pathways (such as the USP28/MYC signaling pathway, ALDH1A1/HIF-1α/VEGF axis, wnt/β-catenin signaling pathway), as well as change the intracellular pH value to promote formation and maintenance, resulting in drug resistance in tumors. By targeting and inhibiting ALDH1 in tumor stem cells, it can enhance the sensitivity of drugs and inhibit the proliferation, differentiation, and metastasis of solid tumor stem cells to some extent. This review discusses the relationship and pathway of ALDH1 with various solid tumors. It proposes that ALDH1 may serve as a diagnosis and therapeutic target for CSC, providing new insights and new strategies for reliable tumor treatment.

CXCR4 inhibitor, AMD3100, down-regulates PARP1 expression and Synergizes with olaparib causing severe DNA damage in BRCA-proficient triple-negative breast cancer

Poly ADP-ribose polymerase inhibitor (PARPi) treatment is effective in triple-negative breast cancer (TNBC) with BRCA mutation. However, its efficacy in BRCA-proficient TNBC remains unexplored. It is, therefore, an exciting proposition to broaden the indication of PARPi for BRCA-proficient TNBC patients. Chemokine receptor (CXCR4) is a transmembrane G protein-coupled receptor, which is involved in cell migration, proliferation, apoptosis, and damage repair, and it initiates many signalling pathways. Although administration of CXCR4 inhibitor alone is not ideal as a target drug, it can play a strong synergistic role in combination with other drugs. We explored the effect of CXCR4 and PARP1 on tumour cell proliferation, migration, metastasis, and apoptosis in vitro and in vivo and found that a CXCR4 inhibitor, AMD3100, enhanced the anti-tumour effect of PARP1 inhibitor, olaparib, on BRCA-proficient TNBC. When CXCR4 was inhibited and silenced, DNA damage repair and DNA replication fork activity were suppressed by up-regulating caspase-3-mediated increase in PARP1 cleavage; in combination with the inhibition of PARP1, AMD3100 resulted in the accumulation of fatal DNA damage and induction of apoptosis. This combination regimen can be effective against BRCA-proficient TNBC.

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.

Plant-Derived Bioactive Compounds in Colorectal Cancer: Insights from Combined Regimens with Conventional Chemotherapy to Overcome Drug-Resistance

Acquired drug resistance represents a major clinical problem and one of the biggest limitations of chemotherapeutic regimens in colorectal cancer. Combination regimens using standard chemotherapeutic agents, together with bioactive natural compounds derived from diet or plants, may be one of the most valuable strategies to overcome drug resistance and re-sensitize chemoresistant cells. In this review, we highlight the effect of combined regimens based on conventional chemotherapeutics in conjunction with well-tolerated plant-derived bioactive compounds, mainly curcumin, resveratrol, and EGCG, with emphasis on the molecular mechanisms associated with the acquired drug resistance.

Quercetin Improves the Anti-angiogenic Property of 5-Fluorouracil on the Human Umbilical Vein Endothelial Cells HUVEC Cell Line

Background: Angiogenesis provides the oxygen and nutrients needed for metastasis and tumor growth, so by inhibiting angiogenesis, metastasis to other parts of the body can be prevented at the first steps of cancer. 5-Fluorouracil (5-FU) as a common chemotherapy drug and Quercetin as a natural compound both have anti-angiogenic properties. Objectives: In the current study improvement of the anti-angiogenic property of 5-FU by combination with quercetin was investigated. Methods: After treating the cells with alone or a combination of drugs the angiogenesis, vascular endothelial growth factor receptors (VEGFRs) gene expression, migration, and viability of the cells were evaluated using chicken chorioallantoic membrane (CAM) assay, real-time RT-PCR, wound healing and MTT assay, respectively. Results: Treatment with alone 5-FU and Que led to a significant reduction in angiogenesis, VEGFR2 and VEGFR1gene expression, migration, and Cell viability. The reductions were significant in the combination state compared to alone treatment. Conclusions: The results showed that the combination treatment with Que with 5-FU enhances the anti-angiogenic property of 5-FU, so it can be proposed as a potential anti-angiogenic and as a result anti-metastatic treatment for future animal studies.

Applications of resveratrol in the treatment of gastrointestinal cancer

Natural product compounds have lately attracted interest in the scientific community as a possible treatment for gastrointestinal (GI) cancer, due to their anti-inflammatory and anticancer properties. There are many preclinical, clinical, and epidemiological studies, suggesting that the consumption of polyphenol compounds, which are abundant in vegetables, grains, fruits, and pulses, may help to prevent various illnesses and disorders from developing, including several GI cancers. The development of GI malignancies follows a well-known path, in which normal gastrointestinal cells acquire abnormalities in their genetic composition, causing the cells to continuously proliferate, and metastasize to other sites, especially the brain and liver. Natural compounds with the ability to affect oncogenic pathways might be possible treatments for GI malignancies, and could easily be tested in clinical trials. Resveratrol is a non-flavonoid polyphenol and a natural stilbene, acting as a phytoestrogen with anti-cancer, cardioprotective, anti-oxidant, and anti-inflammatory properties. Resveratrol has been shown to overcome resistance mechanisms in cancer cells, and when combined with conventional anticancer drugs, could sensitize cancer cells to chemotherapy. Several new resveratrol analogs and nanostructured delivery vehicles with improved anti-GI cancer efficacy, absorption, and pharmacokinetic profiles have already been developed. This present review focuses on the in vitro and in vivo effects of resveratrol on GI cancers, as well as the underlying molecular mechanisms of action.

Synergistic effects of natural compounds and conventional chemotherapeutic agents: recent insights for the development of cancer treatment strategies

Cancer is one of the leading causes of death in the world. Chemotherapy is presented as an option for treatment of this disease, however, low specificity, high resistance rates, toxicity and hypersensitivity reactions, make it necessary to search for therapeutic alternatives that increase the selectivity of treatment, reduce the side effects and enhance its antitumor potential. Natural products are accessible, inexpensive and less toxic sources; in addition, they have multiple mechanisms of action that can potentiate the outcome of chemotherapeutics. In this review, we present evidence on the beneficial effect of the interaction of dietary phytochemicals with chemotherapeutical agents for cancer treatment. This effect is generated by different mechanisms of action such as, increased tumoricidal effect via sensitization of cancer cells, reversing chemoresistance through inhibition of several targets involved in the development of drug resistance and, decreasing chemotherapy-induced toxicity in non-tumoral cells by the promotion of repair mechanisms. Studies discussed in this review will provide a solid basis for the exploration of the potential use of natural products in combination with chemotherapeutical agents, to overcome some of the difficulties that arise in the management of cancer patients.

The Combination of Zerumbone with 5-Fluorouracil for Sensitizing Colorectal Cancer-Associated Fibroblasts to Treatment

The present study aimed to evaluate the synergic effects of combination therapy on 5-fluorouracil (5-FU) resistance-cancer-associated fibroblasts (CAFs) to treatment. Chemotherapy resistance is an important challenge in colorectal cancer (CRC) eradication attention to the tumor microenvironment (TME) is very important. CAFs in the TME play an essential role in cancer chemoresistance and relapse. Additionally, many patients with advanced CRC show resistance to 5-FU therapy. Anti-tumorigenic activities of ZER, a chemopreventive compound derived from the rhizomes of the wild ginger, have been demonstrated. Synergistic and potentiating effects of combination therapy, using herbal and chemical drugs, can improve patients’ response. At the first, CAFs were isolated from a CRC patient and sorted by fluorescent-activated cell sorting (FACS), then, confirmed by flow cytometry, and immunocytochemistry (ICC). The effect of 5-FU and ZER on the cell viability was investigated by MTT assay in a dose and time-dependent manner, after that, the expression of vimentin, β-catenin, and survivin was quantified. Apoptosis, cell cycle, and invasion were analyzed by flow cytometry and scratch test, respectively. ZER could significantly sensitize CAFs cells to 5-FU. A combination of 5-FU + ZER revealed a marked decrease in the marker of interest in both mRNA and protein levels compared to control groups, including 5-FU, ZER treated, and untreated cells. Functional evaluation of cells in different groups presented significant suppression in migration of CAFs and an apparent increase in cell arrest and apoptosis by 5-FU + ZER treatment.

A systematic review of the therapeutic effects of resveratrol in combination with 5-fluorouracil during colorectal cancer treatment: with a special focus on the oxidant, apoptotic, and anti-inflammatory activities

Purpose

5-fluorouracil (5-FU), an effective chemotherapy drug, is commonly applied for colorectal cancer treatment. Nevertheless, its toxicity to normal tissues and the development of tumor resistance are the main obstacles to successful cancer chemotherapy and hence, its clinical application is limited. The use of resveratrol can increase 5-FU-induced cytotoxicity and mitigate the unwanted adverse effects. This study aimed to review the potential therapeutic effects of resveratrol in combination with 5-FU against colorectal cancer.

Methods

According to the PRISMA guideline, a comprehensive systematic search was carried out for the identification of relevant literature in four electronic databases of PubMed, Web of Science, Embase, and Scopus up to May 2021 using a pre-defined set of keywords in their titles and abstracts. We screened 282 studies in accordance with our inclusion and exclusion criteria. Thirteen articles were finally included in this systematic review.

Results

The in vitro findings showed that proliferation inhibition of colorectal cancer cells in the groups treated by 5-FU was remarkably higher than the untreated groups and the co-administration of resveratrol remarkably increased cytotoxicity induced by 5-FU. The in vivo results demonstrated a decrease in tumor growth of mice treated by 5-FU than the untreated group and a dramatic decrease was observed following combined treatment of resveratrol and 5-FU. It was also found that 5-FU alone and combined with resveratrol could regulate the cell cycle profile of colorectal cancer cells. Moreover, this chemotherapeutic agent induced the biochemical and histopathological changes in the cancerous cells/tissues and these alterations were synergized by resveratrol co-administration (for most of the cases), except for the inflammatory mediators.

Conclusion

The results obtained from this systematic review demonstrated that co-administration of resveratrol could sensitize the colorectal cancer cells to 5-FU treatment via various mechanisms, including regulation of cell cycle distribution, oxidant, apoptosis, anti-inflammatory effects.

Traditional Chinese Medicines as Effective Reversals of Epithelial-Mesenchymal Transition Induced-Metastasis of Colorectal Cancer: Molecular Targets and Mechanisms

Colorectal cancer (CRC) is the third most common type of cancer worldwide. Distant metastasis is the major cause of cancer-related mortality in patients with CRC. Epithelial-mesenchymal transition (EMT) is a critical process triggered during tumor metastasis, which is also the main impetus and the essential access within this duration. Therefore, targeting EMT-related molecular pathways has been considered a novel strategy to explore effective therapeutic agents against metastatic CRC. Traditional Chinese medicines (TCMs) with unique properties multi-target and multi-link that exert their therapeutic efficacies holistically, which could inhibit the invasion and metastasis ability of CRC cells via inhibiting the EMT process by down-regulating transforming growth factor-β (TGF-β)/Smads, PI3K/Akt, NF-κB, Wnt/β-catenin, and Notch signaling pathways. The objective of this review is to summarize and assess the anti-metastatic effect of TCM-originated bioactive compounds and Chinese medicine formulas by mediating EMT-associated signaling pathways in CRC therapy, providing a foundation for further research on the exact mechanisms of action through which TCMs affect EMT transform in CRC.

The tumor immune-microenvironment in gastric cancer

AIMS AND BACKGROUND

The tumor microenvironment significantly influences malignant behavior and progression. Many components are involved in the tumor microenvironment, including extracellular matrix, stromal cells, immune and inflammatory cells, as well as cytokines that promote tumor development with complex interactions through the exchange of molecular information. It is now known that tumor immune escape may be influenced by the tumor microenvironment. The aim of this work is to conduct a review of the tumor immune-microenvironment in gastric cancer.

METHODS

We review the current knowledge of several immune cells involved in the gastric tumor microenvironment. In addition, a brief description of immunotherapy strategies for gastric cancer is also reviewed.

CONCLUSIONS

Among immune cell populations, lymphocytes, macrophages, dendritic cells and myeloid-derived suppressor cells are revealed to make the difference in promoting or suppressing gastric tumorigenesis, either directly or indirectly, via regulating the immune responses. Understanding these interactions in detail within the tumor immune-microenvironment will contribute to unraveling new therapeutic targets.

Molecular Basis of Resveratrol-Induced Resensitization of Acquired Drug-Resistant Cancer Cells

Multidrug resistance (MDR) to anticancer drugs remains a serious obstacle to the success of cancer chemotherapy. Resveratrol, a polyphenol, present in natural products exerts anticancer activity and acts as a potential MDR inhibitor in various drug-resistant cancer cells. In the process of resensitization of drug-resistant cancer cells, resveratrol has been shown to interfere with ABC transporters and drug-metabolizing enzymes, increase DNA damage, inhibit cell cycle progression, and induce apoptosis and autophagy, as well as prevent the induction of epithelial to mesenchymal transition (EMT) and cancer stem cells (CSCs). This review summarizes the mechanisms by which resveratrol counteracts MDR in acquired drug-resistant cancer cell lines and provides a critical basis for understanding the regulation of MDR as well as the development of MDR-inhibiting drugs.

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.

CENPO regulated proliferation and apoptosis of colorectal cancer in a p53-dependent manner

Colorectal cancer (CRC) is considered to be a leading cause of cancer-related death. Centromere protein O (CENPO) can prevent the separation of sister chromatids and cell death after spindle injury. Nevertheless, the role of CENPO in CRC has not been reported. The expression level of CENPO in CRC was revealed by TCGA database and immunohistochemical (IHC) staining. Subsequently, the loss-of-function assays were performed to identified the role of CENPO in CRC in vitro and in vivo. Our data demonstrated that CENPO was highly expressed in CRC. The expression of CENPO was positively correlated with the deterioration of CRC. Moreover, CENPO knockdown inhibited the malignant phenotypes of CRC cells, which was characterized by slowed proliferation, cycle repression at G2, promotion of apoptosis, reduced migration and weakened tumorigenesis. Furthermore, CENPO knockdown downregulated the expression of N-cadherin, Vimentin, Snail, CCND1, PIK3CA and inhibited AKT phosphorylation in CRC cells. Moreover, the function of CENPO in regulating proliferation and apoptosis depended on p53. In summary, CENPO may play a promoting role in CRC through the epithelial mesenchymal transition (EMT) and PI3K/AKT signaling pathway, which can be regarded as a molecular therapeutic target for CRC.

Stemness, Inflammation and Epithelial-Mesenchymal Transition in Colorectal Carcinoma: The Intricate Network

In global cancer statistics, colorectal carcinoma (CRC) ranks third by incidence and second by mortality, causing 10.0% of new cancer cases and 9.4% of oncological deaths worldwide. Despite the development of screening programs and preventive measures, there are still high numbers of advanced cases. Multiple problems compromise the treatment of metastatic colorectal cancer, one of these being cancer stem cells—a minor fraction of pluripotent, self-renewing malignant cells capable of maintaining steady, low proliferation and exhibiting an intriguing arsenal of treatment resistance mechanisms. Currently, there is an increasing body of evidence for intricate associations between inflammation, epithelial–mesenchymal transition and cancer stem cells. In this review, we focus on inflammation and its role in CRC stemness development through epithelial–mesenchymal transition.

Combined Effects of Resveratrol and Vitamin E From Peanut Seeds and Sprouts on Colorectal Cancer Cells

Resveratrol (RES) and Vitamin E (VE) are anti-cancer active ingredients with relatively high content in peanut seeds and sprouts. This study aimed to determine the synergistic inhibitory effect of RES and VE on colorectal cancer. Using 5-FU as a positive drug control, the effect of RES combined with VE on HCT-8 cells was determined, and cell viability was detected using the cell-counting kit 8 (CCK8) method. Cell morphology changes were observed using optical microscopy. Cell migration ability was evaluated by the scratch test, while cell colonies were determined by the cloning test formation ability. Apoptosis status was assessed by flow cytometry and nuclear staining by DAPI, and the expression level of apoptosis-related proteins was determined by western blotting. Compared with the single component group, the RES combined with VE group significantly inhibited the growth and proliferation of HCT-8 intestinal cancer cells in vitro. The RES combined with VE group had a greater impact on cell morphology changes and cell colony formation and significantly reduced cell migration ability and intestinal cancer cell apoptosis (p < 0.05). Additionally, combined treatment with RES and VE significantly upregulated the expression of pro-apoptotic proteins BAX, caspase-3, caspase-8, and caspase-9, and downregulated the expression of anti-apoptotic protein BCL-2, compared to the single component treatment. RES combined with VE is effective in promoting intestinal cancer cell apoptosis. This study demonstrated the significant positive synergy of RES and VE on HCT-8 cells, providing a new perspective for more effective use of RES.

Combination of resveratrol and BIBR1532 inhibits proliferation of colon cancer cells by repressing expression of LncRNAs

Colorectal cancer (CRC) is the third most common cancer worldwide. The development of tumor drug resistance is observed in the treatment of CRC. Combinations of anticancer agents are attracting considerable interest in order to overcome drug resistance in CRC. This study aims to investigate the effect of resveratrol and BIBR1532, either alone or in combination, on the cell viability as well as on expression of long non-coding RNAs (LncRNAs) for HT-29 colon adenocarcinoma cells. The cytotoxic effects of resveratrol and BIBR1532 on HT-29 cells were determined using WST-1 test. Flow cytometry was used to determine apoptotic cell death after treatments. Real-Time PCR was used to identify expression of LncRNAs after treatments. LncExpDB and GEPIA2 were used to evaluate expression profiles of LncRNAs, whose expression levels were decreased in HT-29 cells after treatments, in normal tissues and colon adenocarcinoma tumors. IC₅₀ concentrations of BIBR1532 and resveratrol were found to be 50.81 μM at 48 h and 86.23 μM at 72 h, respectively. Combination index value was 1.07617. BIBR1532, resveratrol, or their combination reduced the cell viability of HT-29 cells. CCAT1, CRNDE, HOTAIR, PCAT1, PVT1, SNHG16 were down-regulated after treatments. In silico analysis revealed that LncRNAs whose expression levels were decreased after treatments were associated with CRC. Resveratrol, BIBR1532, or their combination may have anti-proliferative effect on colorectal cancer cells through repressing expression of LncRNAs that are involved in progression of CRC.

Role of Episamarcandin in Promoting the Apoptosis of Human Colon Cancer HCT116 Cells through the PI3K-Akt Signaling Pathway

This study identifies the active ingredients of Ferula sinkiangensis and investigates the role and mechanism of episamarcandin in colon cancer cells. The silica gel column chromatography was utilized to separate the chemical components of Ferula sinkiangensis. Sephadex LH-20 and semipreparative HPLC were adopted for further separation and purification. The compound episamarcandin showed good anticolon cancer activity among the 13 monomeric compounds obtained. Its effects on the apoptosis, cell cycle, and invasion and migration of colon cancer HCT 116 cells and PI3K-Akt signaling pathway were further investigated. The results showed that, similar to positive control cisplatin, episamarcandin inhibited the proliferation, promoted the apoptosis, arrested cells at G0/G1 phase, and suppressed migration and invasion of HCT 116 cells. A large number of apoptotic HCT 116 cells were observed under a transmission electron microscope. Fluorescence real-time quantitative PCR and western blot analysis showed that episamarcandin increased the expression of PTEN, p53, and Bax and decreased the expression of P-Akt, Akt, mTOR, Bcl-xl, and Bcl-2. Conclusively, episamarcandin may inhibit cell proliferation, migration, and invasion and promote the apoptosis of human colon cancer HCT 116 cells possibly through the PI3K-Akt signaling pathway.

KIF15 knockdown suppresses gallbladder cancer development

Gallbladder cancer (GBC) is commonly regarded as one of the most lethal malignant tumor types with poor prognosis. Kinesin family member 15 (KIF15) is reported to be tightly related with progression of multiple cancer types which, however, has not been clarified in GBC so far. KIF15 was significantly up-regulated in clinical GBC tissues compared with that in para-carcinoma tissues and the expression level was also correlated with tumor malignancies. In addition to tissues, GBC cells also exhibited a high expression abundance of KIF15. After down-regulating KIF15 via lentiviral transfection, GBC cell proliferation and migration were both inhibited, while cell apoptosis was promoted markedly. Likewise, silencing KIF15 significantly interfered the growth of nude mouse xenografts. Our experiments in GBC cell lines also demonstrated that KIF15 overexpression accelerated cell proliferation but lessened cell apoptosis in both GBC-SD and SGC-996 cells. Further investigation of the mechanism occurring in GBC inhibition mediated by KIF15 knockdown revealed that KIF15 deficiency led to decreased activity of several signaling pathways (TNF, PI3K/AKT and MAPK), a reduction of CDK6 expression regulated by enhanced p21, and HSP60 absence. Following the treatment of shCtrl- and shKIF15-transfected cells with AKT activator, we found that anti-tumor effects resulting from KIF15 deficiency could be relieved by AKT activator in both experimental cells. Overall, for the first time, we demonstrated that KIF15 was overexpressed in GBC and displayed a close relationship between KIF15 levels and GBC clinical stages. Furthermore, low expression of KIF15 resulted in obvious anti-tumor effects.

Targeting Cancer Stem Cells by Dietary Agents: An Important Therapeutic Strategy against Human Malignancies

As a multifactorial disease, treatment of cancer depends on understanding unique mechanisms involved in its progression. The cancer stem cells (CSCs) are responsible for tumor stemness and by enhancing colony formation, proliferation as well as metastasis, and these cells can also mediate resistance to therapy. Furthermore, the presence of CSCs leads to cancer recurrence and therefore their complete eradication can have immense therapeutic benefits. The present review focuses on targeting CSCs by natural products in cancer therapy. The growth and colony formation capacities of CSCs have been reported can be attenuated by the dietary agents. These compounds can induce apoptosis in CSCs and reduce tumor migration and invasion via EMT inhibition. A variety of molecular pathways including STAT3, Wnt/β-catenin, Sonic Hedgehog, Gli1 and NF-κB undergo down-regulation by dietary agents in suppressing CSC features. Upon exposure to natural agents, a significant decrease occurs in levels of CSC markers including CD44, CD133, ALDH1, Oct4 and Nanog to impair cancer stemness. Furthermore, CSC suppression by dietary agents can enhance sensitivity of tumors to chemotherapy and radiotherapy. In addition to in vitro studies, as well as experiments on the different preclinical models have shown capacity of natural products in suppressing cancer stemness. Furthermore, use of nanostructures for improving therapeutic impact of dietary agents is recommended to rapidly translate preclinical findings for clinical use.

Natural Products for Pancreatic Cancer Treatment: From Traditional Medicine to Modern Drug Discovery

Pancreatic cancer, the seventh most lethal cancer around the world, is considered complicated cancer due to poor prognosis and difficulty in treatment. Despite all the conventional treatments, including surgical therapy and chemotherapy, the mortality rate is still high. Therefore, the possibility of using natural products for pancreatic cancer is increasing. In this study, 68 natural products that have anti-pancreatic cancer effects reported within five years were reviewed. The mechanisms of anti-cancer effects were divided into four types: apoptosis, anti-metastasis, anti-angiogenesis, and anti-resistance. Most of the studies were conducted for natural products that induce apoptosis in pancreatic cancer. Among them, plant extracts such as Eucalyptus microcorys account for the major portion. Some natural products, including Moringa, Coix seed, etc., showed multi-functional properties. Natural products could be beneficial candidates for treating pancreatic cancer.

Multitargeting Effects of Calebin A on Malignancy of CRC Cells in Multicellular Tumor Microenvironment

Background

Tumor microenvironment (TME) provides the essential prerequisite niche for promoting cancer progression and metastasis. Calebin A, a component of Curcuma longa, has long been investigated as a safe multitargeted agent with antitumor and anti-inflammatory properties. However, the multicellular-TME-induced malignancy and the antitumorigenic potential of Calebin A on colorectal cancer (CRC) cells in 3D-alginate cultures are not yet understood, and more in-depth research is needed.

Methods

3D-alginate tumor cultures (HCT116 cells) in the multicellular proinflammatory TME (fibroblast cells/T lymphocytes), tumor necrosis factor beta (TNF-β)-TME (fibroblast cells/TNF-β) were treated with/without Calebin A to address the pleiotropic actions of Calebin A in the CRC.

Results

We found that Calebin A downmodulated proliferation, vitality, and migration of HCT116 cells in 3D-alginate cultures in multicellular proinflammatory TME or TNF-β-TME. In addition, Calebin A suppressed TNF-β-, similar to multicellular-TME-induced phosphorylation of nuclear factor kappa B (NF-κB) in a concentration-dependent manner. NF-κB-promoting proinflammatory mediators, associated with tumor growth and antiapoptotic molecules (i.e.,MMP-9, CXCR4, Ki-67, β1-integrin, and Caspase-3) and its translocation to the nucleus in HCT116 cells, were increased in both TME cultures. The multicellular-TME cultures further induced the survival of cancer stem cells (CSCs) (upregulation of CD133, CD44, and ALDH1). Last but not the least, Calebin A suppressed multicellular-, similar to TNF-β-TME-induced rigorous upregulation of NF-κB phosphorylation, various NF-κB-regulated gene products, CSCs activation, and survival in 3D-alginate tumor cultures.

Conclusions

The downmodulation of multicellular proinflammatory-, similar to TNF-β-TME-induced CRC proliferation, survival, and migration by the multitargeting agent Calebin A could be a new therapeutic strategy to suppress inflammation and CRC tumorigenesis.

Dietary Polyphenols: Promising Adjuvants for Colorectal Cancer Therapies

Simple Summary

Colorectal cancer is a leading cause of death worldwide. Despite the development of novel surgical and therapeutic strategies, 50% of patients relapse after treatment. Therapy failure, due to low efficacy, adverse effects and drug resistance, is thus a major concern. The idea of combining standard therapy with non-toxic bioactive natural compounds is a recent topic in cancer research and aims to increase the efficacy of current antitumor therapies while reducing drug toxicity and adverse effects. In recent years, several studies have explored the capacity of polyphenols, dietary bioactive compounds enriched in fruit and vegetables, to act as adjuvants to improve colorectal cancer therapy. In the present review, we discuss these studies, highlighting the mechanisms underlying the adjuvant effect, and bring out the potential of this novel therapeutic approach as well as the critical issues related to clinical application.

Abstract

Colorectal cancer (CRC) is a major cancer type and a leading cause of death worldwide. Despite advances in therapeutic management, the current medical treatments are not sufficient to control metastatic disease. Treatment-related adverse effects and drug resistance strongly contribute to therapy failure and tumor recurrence. Combination therapy, involving cytotoxic treatments and non-toxic natural compounds, is arousing great interest as a promising more effective and safer alternative. Polyphenols, a heterogeneous group of bioactive dietary compounds mainly found in fruit and vegetables, have received great attention for their capacity to modulate various molecular pathways active in cancer cells and to affect host anticancer response. This review provides a summary of the most recent (i.e., since 2016) preclinical and clinical studies using polyphenols as adjuvants for CRC therapies. These studies highlight the beneficial effects of dietary polyphenols in combination with cytotoxic drugs or irradiation on both therapy outcome and drug resistance. Despite substantial preclinical evidence, data from a few pilot clinical trials are available to date with promising but still inconclusive results. Larger randomized controlled studies and polyphenol formulations with improved bioavailability are needed to translate the research progress into clinical applications and definitively prove the added value of these molecules in CRC management.

A Systematic Review of the Potential Chemoprotective Effects of Resveratrol on Doxorubicin-Induced Cardiotoxicity: Focus on the Antioxidant, Antiapoptotic, and Anti-Inflammatory Activities

PURPOSE

Although doxorubicin chemotherapeutic drug is commonly used to treat various solid and hematological tumors, its clinical use is restricted because of its adverse effects on the normal cells/tissues, especially cardiotoxicity. The use of resveratrol may mitigate the doxorubicin-induced cardiotoxic effects. For this aim, we systematically reviewed the potential chemoprotective effects of resveratrol against the doxorubicin-induced cardiotoxicity.

METHODS

In the current study, a systematic search was performed based on Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guideline for the identification of all relevant studies on "the role of resveratrol on doxorubicin-induced cardiotoxicity" in the electronic databases of Web of Science, PubMed, and Scopus up to March 2021 using search terms in their titles and abstracts. Two hundred and eighteen articles were screened in accordance with a predefined set of inclusion and exclusion criteria. Finally, 33 eligible articles were included in this systematic review.

RESULTS

The in vitro and in vivo findings demonstrated a decreased cell survival, increased mortality, decreased heart weight, and increased ascites in the doxorubicin-treated groups compared to the control groups. The combined treatment of resveratrol and doxorubicin showed an opposite pattern than the doxorubicin-treated groups alone. Furthermore, this chemotherapeutic agent induced the biochemical and histopathological changes on the cardiac cells/tissue; however, the results (for most of the cases) revealed that these alterations induced by doxorubicin were reversed near to normal levels (control groups) by resveratrol coadministration.

CONCLUSION

The results of this systematic review stated that coadministration of resveratrol alleviates the doxorubicin-induced cardiotoxicity. Resveratrol exerts these chemoprotective effects through several main mechanisms of antioxidant, antiapoptosis, and anti-inflammatory.

Analysis of Several Pathways for Efficient Killing of Prostate Cancer Stem Cells: A Central Role of NF-κB RELA

Prostate cancer is a common cause of death worldwide. Here, we isolated cancer stem cells (CSCs) from four adenocarcinomas of the prostate (Gleason scores from 3 + 3 up to 4 + 5). CSCs were characterized by the expression of the stem cell markers TWIST, the epithelial cell adhesion molecule (EPCAM), the transcription factors SNAI1 (SNAIL) and SNAI2 (SLUG) and cancer markers such as CD44 and prominin-1 (CD133). All investigated CSC populations contained a fraction highly positive for aldehyde dehydrogenase (ALDH) function and displayed robust expressions of programmed cell death 1 (PD-1) ligands. Furthermore, we investigated immunotherapeutic approaches but had no success even with the clinically used PD-1 inhibitor pembrolizumab. In addition, we studied another death-inducing pathway via interferon gamma signaling and detected high-level upregulations of human leukocyte antigen A (HLA-A) and beta 2-microglobulin (B2M) with only moderate killing efficacy. To examine further killing mechanisms in prostate cancer stem cells (PCSCs), we analyzed NF-κB signaling. Surprisingly, two patient-specific populations of PCSCs were found: one with canonical NF-κB signaling and another one with blunted NF-κB activation, which can be efficiently killed by tumor necrosis factor (TNF). Thus, culturing of PCSCs and analysis of respective NF-κB induction potency after surgery might be a powerful tool for optimizing patient-specific treatment options, such as the use of TNF-inducing chemotherapeutics and/or NF-κB inhibitors.

Resveratrol as an Adjuvant for Normal Tissues Protection and Tumor Sensitization

Cancer is one of the most complicated diseases in present-day medical science. Yearly, several studies suggest various strategies for preventing carcinogenesis. Furthermore, experiments for the treatment of cancer with low side effects are ongoing. Chemotherapy, targeted therapy, radiotherapy and immunotherapy are the most common non-invasive strategies for cancer treatment. One of the most challenging issues encountered with these modalities is low effectiveness, as well as normal tissue toxicity for chemo-radiation therapy. The use of some agents as adjuvants has been suggested to improve tumor responses and also alleviate normal tissue toxicity. Resveratrol, a natural flavonoid, has attracted a lot of attention for the management of both tumor and normal tissue responses to various modalities of cancer therapy. As an antioxidant and anti-inflammatory agent, in vitro and in vivo studies show that it is able to mitigate chemo-radiation toxicity in normal tissues. However, clinical studies to confirm the usage of resveratrol as a chemo-radioprotector are lacking. In addition, it can sensitize various types of cancer cells to both chemotherapy drugs and radiation. In recent years, some clinical studies suggested that resveratrol may have an effect on inducing cancer cell killing. Yet, clinical translation of resveratrol has not yielded desirable results for the combination of resveratrol with radiotherapy, targeted therapy or immunotherapy. In this paper, we review the potential role of resveratrol for preserving normal tissues and sensitization of cancer cells in combination with different cancer treatment modalities.

Resveratrol and Its Analogs: Potent Agents to Reverse Epithelial-to-Mesenchymal Transition in Tumors

Epithelial-to-mesenchymal transition (EMT), a complicated program through which polarized epithelial cells acquire motile mesothelial traits, is regulated by tumor microenvironment. EMT is involved in tumor progression, invasion and metastasis via reconstructing the cytoskeleton and degrading the tumor basement membrane. Accumulating evidence shows that resveratrol, as a non-flavonoid polyphenol, can reverse EMT and inhibit invasion and migration of human tumors via diverse mechanisms and signaling pathways. In the present review, we will summarize the detailed mechanisms and pathways by which resveratrol and its analogs (e.g. Triacetyl resveratrol, 3,5,4'-Trimethoxystilbene) might regulate the EMT process in cancer cells to better understand their potential as novel anti-tumor agents. Resveratrol can also reverse chemoresistance via EMT inhibition and improvement of the antiproliferative effects of conventional treatments. Therefore, resveratrol and its analogs have the potential to become novel adjunctive agents to inhibit cancer metastasis, which might be partly related to their blocking of the EMT process.

Resveratrol Enhances Inhibition Effects of Cisplatin on Cell Migration and Invasion and Tumor Growth in Breast Cancer MDA-MB-231 Cell Models In Vivo and In Vitro

Triple-negative breast cancer (TNBC) is a refractory type of breast cancer that does not yet have clinically effective drugs. The aim of this study is to investigate the synergistic effects and mechanisms of resveratrol combined with cisplatin on human breast cancer MDA-MB-231 (MDA231) cell viability, migration, and invasion in vivo and in vitro. In vitro, MTS assays showed that resveratrol combined with cisplatin inhibits cell viability as a concentration-dependent manner, and produced synergistic effects (CI < 1). Transwell assay showed that the combined treatment inhibits TGF-β1-induced cell migration and invasion. Immunofluorescence assays confirmed that resveratrol upregulated E-cadherin expression and downregulated vimentin expression. Western blot assay demonstrated that resveratrol combined with cisplatin significantly reduced the expression of fibronectin, vimentin, P-AKT, P-PI3K, P-JNK, P-ERK, Sma2, and Smad3 induced by TGF-β1 (p < 0.05), and increased the expression of E-cadherin (p < 0.05), respectively. In vivo, resveratrol enhanced tumor growth inhibition and reduced body weight loss and kidney function impairment by cisplatin in MDA231 xenografts, and significantly reduced the expressions of P-AKT, P-PI3K, Smad2, Smad3, P-JNK, P-ERK, and NF-κB in tumor tissues (p < 0.05). These results indicated that resveratrol combined with cisplatin inhibits the viability of breast cancer MDA231 cells synergistically, and inhibits MDA231 cells invasion and migration through Epithelial-mesenchymal transition (EMT) approach, and resveratrol enhanced anti-tumor effect and reduced side of cisplatin in MDA231 xenografts. The mechanism may be involved in the regulations of PI3K/AKT, JNK, ERK and NF-κB expressions.

Andrographis overcomes 5-fluorouracil-associated chemoresistance through inhibition of DKK1 in colorectal cancer

Colorectal cancer (CRC) ranks as the third leading cause of cancer-related deaths in the USA. 5-Fluorouracil (5FU)-based chemotherapeutic drug remains a mainstay of CRC treatment. Unfortunately, ~50-60% of patients eventually develop resistance to 5FU, leading to poor survival outcomes. Our previous work revealed that andrographis enhanced 5FU-induced anti-cancer activity, but the underlying mechanistic understanding largely remains unclear. In this study, we first established 5FU-resistant (5FUR) CRC cells and observed that combined treatment with andrographis-5FU in 5FUR cells exhibited superior effect on cell viability, proliferation, and colony formation capacity compared with individual treatments (P < 0.001). To identify key genes and pathways responsible for 5FU resistance, we analyzed genome-wide transcriptomic profiling data from CRC patients who either responded or did not respond to 5FU. Among a panel of differentially expressed genes, Dickkopf-1 (DKK1) overexpression was a critical event for 5FU resistance. Moreover, andrographis significantly downregulated 5FU-induced DKK1 overexpression, accompanied with enhanced anti-tumor effects by abrogating downstream Akt-phosphorylation. In line with in vitro findings, andrographis enhanced 5FU-induced anti-cancer activity in mice xenografts and patient-derived tumoroids (P < 0.01). In conclusion, our data provide novel evidence for andrographis-mediated reversal of 5FU resistance, highlighting its potential role as an adjunct to conventional chemotherapy in CRC.

The role of tumor-associated macrophages in osteosarcoma progression - therapeutic implications

BACKGROUND

Osteosarcoma (OS) is the most common primary malignant bone tumor. Compared with previous treatment modalities, such as amputation, more recent comprehensive treatment modalities based on neoadjuvant chemotherapy combined with limb salvage surgery have improved the survival rates of patients. Osteosarcoma treatment has, however, not further improved in recent years. Therefore, attention has shifted to the tumor microenvironment (TME) in which osteosarcoma cells are embedded. Therapeutic targets in the TME may be key to improving osteosarcoma treatment. Tumor-associated macrophages (TAMs) are the most common immune cells within the TME. TAMs in osteosarcoma may account for over 50% of the immune cells, and may play important roles in tumorigenesis, angiogenesis, immunosuppression, drug resistance and metastasis. Knowledge on the role of TAMs in the development, progression and treatment of osteosarcoma is gradually improving, although different or even opposing opinions still remain.

CONCLUSIONS

TAMs may participate in the malignant progression of osteosarcoma through self-polarization, the promotion of blood vessel and lymphatic vessel formation, immunosuppression, and drug resistance. Besides, various immune checkpoint proteins expressed on the surface of TAMs, such as PD-1 and CD47, provide the possibility of the application of immune checkpoint inhibitors. Several clinical trials have been carried out and/or are in progress. Mifamotide and the immune checkpoint inhibitor Camrelizumab were both found to be effective in prolonging progression-free survival. Thus, TAMs may serve as attractive therapeutic targets. Targeting TAMs as a complementary therapy is expected to improve the prognosis of osteosarcoma. Further efforts may be made to identify potential beneficiaries of TAM-targeted therapies.

Resveratrol as Chemosensitizer Agent: State of Art and Future Perspectives

Resistance to chemotherapy still remains a major challenge in the clinic, impairing the quality of life and survival rate of patients. The identification of unconventional chemosensitizing agents is therefore an interesting aspect of cancer research. Resveratrol has emerged in the last decades as a fascinating molecule, able to modulate several cancer-related molecular mechanisms, suggesting a possible application as an adjuvant in cancer management. This review goes deep into the existing literature concerning the possible chemosensitizing effect of resveratrol associated with the most conventional chemotherapeutic drugs. Despite the promising effects observed in different cancer types in in vitro studies, the clinical translation still presents strong limitations due to the low bioavailability of resveratrol. Recently, efforts have been moved in the field of drug delivery to identifying possible strategies/formulations useful for a more effective administration. Despite the necessity of a huge implementation in this research area, resveratrol appears as a promising molecule able to sensitize resistant tumors to drugs, suggesting its potential use in therapy-refractory cancer patients.

Resveratrol's Anti-Cancer Effects through the Modulation of Tumor Glucose Metabolism

Simple Summary

The prevention and treatment of cancer is an ongoing medical challenge. In the context of personalized medicine, the well-studied polyphenol resveratrol could complement classical tumor therapy. It may affect key processes such as inflammation, angiogenesis, proliferation, metastasis, glucose metabolism, and apoptosis in various cancers because resveratrol acts as a multi-targeting agent by modulating multiple signal transduction pathways. This review article focuses on resveratrol’s ability to modify tumor glucose metabolism and its associated therapeutic capacity. Resveratrol reduces glucose uptake and glycolysis by affecting Glut1, PFK1, HIF-1α, ROS, PDH, and the CamKKB/AMPK pathway. It also inhibits cell growth, invasion, and proliferation by targeting NF-kB, Sirt1, Sirt3, LDH, PI-3K, mTOR, PKM2, R5P, G6PD, TKT, talin, and PGAM. In addition, resveratrol induces apoptosis by targeting integrin, p53, LDH, and FAK. In conclusion, resveratrol has many potentials to intervene in tumor processes if bioavailability can be increased and this natural compound can be used selectively.

Abstract

Tumor cells develop several metabolic reprogramming strategies, such as increased glucose uptake and utilization via aerobic glycolysis and fermentation of glucose to lactate; these lead to a low pH environment in which the cancer cells thrive and evade apoptosis. These characteristics of tumor cells are known as the Warburg effect. Adaptive metabolic alterations in cancer cells can be attributed to mutations in key metabolic enzymes and transcription factors. The features of the Warburg phenotype may serve as promising markers for the early detection and treatment of tumors. Besides, the glycolytic process of tumors is reversible and could represent a therapeutic target. So-called mono-target therapies are often unsafe and ineffective, and have a high prevalence of recurrence. Their success is hindered by the ability of tumor cells to simultaneously develop multiple chemoresistance pathways. Therefore, agents that modify several cellular targets, such as energy restriction to target tumor cells specifically, have therapeutic potential. Resveratrol, a natural active polyphenol found in grapes and red wine and used in many traditional medicines, is known for its ability to target multiple components of signaling pathways in tumors, leading to the suppression of cell proliferation, activation of apoptosis, and regression in tumor growth. Here, we describe current knowledge on the various mechanisms by which resveratrol modulates glucose metabolism, its potential as an imitator of caloric restriction, and its therapeutic capacity in tumors.