Silibinin inhibits β-catenin/ZEB1 signaling and suppresses bladder cancer metastasis via dual-blocking epithelial-mesenchymal transition and stemness

Natural products and derivatives in renal, urothelial and testicular cancers: Targeting signaling pathways and therapeutic potential

BACKGROUND

Natural products have demonstrated significant potential in cancer drug discovery, particularly in renal cancer (RCa), urothelial carcinoma (UC), and testicular cancer (TC).

PURPOSE

This review aims to examine the effects of natural products on RCa, UC and TC.

STUDY DESIGN

systematic review METHODS: PubMed and Web of Science databases were retrieved to search studies about the effects of natural products and derivatives on these cancers. Relevant publications in the reference list of enrolled studies were also checked.

RESULTS

This review highlighted their diverse impacts on key aspects such as cell growth, apoptosis, metastasis, therapy response, and the immune microenvironment. Natural products not only hold promise for novel drug development but also enhance the efficacy of existing chemotherapy and immunotherapy. Importantly, we exert their effects through modulation of critical pathways and target genes, including the PI3K/AKT pathway, NF-κB pathway, STAT pathway and MAPK pathway, among others in RCa, UC, and TC.

CONCLUSION

These mechanistic insights provide valuable guidance for researchers, facilitating the selection of promising natural products for cancer management and offering potential avenues for further gene regulation studies in the context of cancer treatment.

Unravelling the role of Silibinin in targeting CD44+ cancer stem cells: Therapeutic implications, effective strategies and approaches

CD44+ cancer stem cells (CSCs) are believed to account for drug resistance and tumour recurrence due to their potential to self-renew and differentiate into heterogeneous lineages. Therefore, efficient treatment strategies targeting and eliminating these CSCs are required. The flavonolignan, Silibinin, has gained immense attention in targeting CD44+ CSCs as it alters functional properties like cell cycle arrest, apoptosis, inhibition of invasion and metastasis and also inhibits a range of molecular pathways. However, its limited bioavailability is a major hurdle in asserting Silibinin as a translational therapeutic agent. Combinatorial therapy of Silibinin with conventional chemotherapeutic drugs is an alternative approach in targeting CD44+ CSCs as it increases the efficacy and reduces the cytotoxicity of chemotherapeutic drugs, thus preventing drug resistance. Certain Silibinin-conjugated nano-formulations have also been successfully developed, through which there is improved absorptivity/bioavailability of Silibinin and a decrease in the concentration of therapeutic drugs leading to reduced cytotoxicity. In this review, we summarise the effectiveness of the synergistic therapeutic approach for Silibinin in targeting the molecular mechanisms of CD44+ CSCs and emphasise the potential role of Silibinin as a novel therapeutic agent.

Modulation of hypoxia-inducible factor-1 signaling pathways in cancer angiogenesis, invasion, and metastasis by natural compounds: a comprehensive and critical review

Tumor cells employ multiple signaling mediators to escape the hypoxic condition and trigger angiogenesis and metastasis. As a critical orchestrate of tumorigenic conditions, hypoxia-inducible factor-1 (HIF-1) is responsible for stimulating several target genes and dysregulated pathways in tumor invasion and migration. Therefore, targeting HIF-1 pathway and cross-talked mediators seems to be a novel strategy in cancer prevention and treatment. In recent decades, tremendous efforts have been made to develop multi-targeted therapies to modulate several dysregulated pathways in cancer angiogenesis, invasion, and metastasis. In this line, natural compounds have shown a bright future in combating angiogenic and metastatic conditions. Among the natural secondary metabolites, we have evaluated the critical potential of phenolic compounds, terpenes/terpenoids, alkaloids, sulfur compounds, marine- and microbe-derived agents in the attenuation of HIF-1, and interconnected pathways in fighting tumor-associated angiogenesis and invasion. This is the first comprehensive review on natural constituents as potential regulators of HIF-1 and interconnected pathways against cancer angiogenesis and metastasis. This review aims to reshape the previous strategies in cancer prevention and treatment.

Long intergenic non-protein coding RNA 115 (Linc00115): A notable oncogene in human malignancies

Long noncoding RNAs (LncRNAs) are RNA transcripts ranging from 200 to 1000 nucleotides that have emerged as critical regulators of gene expression. Growing evidence highlights their involvement in tumor development. In particular, long intergenic non-protein coding RNA115 (Linc00115) has been identified as an oncogene across various human malignancies, with aberrant expression strongly linked to poor clinical outcomes in cancer patients. This review aims to delve into the expression patterns of Linc00115 and elucidate the underlying molecular mechanisms behind its oncogenic properties. Moreover, we discuss the potential utility of Linc00115 as a valuable diagnostic and prognostic biomarker in cancer.

Targeting the key players of phenotypic plasticity in cancer cells by phytochemicals

Plasticity of phenotypic traits refers to an organism's ability to change in response to environmental stimuli. As a result, the response may alter an organism's physiological state, morphology, behavior, and phenotype. Phenotypic plasticity in cancer cells describes the considerable ability of cancer cells to transform phenotypes through non-genetic molecular signaling activities that promote therapy evasion and tumor metastasis via amplifying cancer heterogeneity. As a result of metastable phenotypic state transitions, cancer cells can tolerate chemotherapy or develop transient adaptive resistance. Therefore, new findings have paved the road in identifying factors and agents that inhibit or suppress phenotypic plasticity. It has also investigated novel multitargeted agents that may promise new effective strategies in cancer treatment. Despite the efficiency of conventional chemotherapeutic agents, drug toxicity, development of resistance, and high-cost limit their use in cancer therapy. Recent research has shown that small molecules derived from natural sources are capable of suppressing cancer by focusing on the plasticity of phenotypic responses. This systematic, comprehensive, and critical review analyzes the current state of knowledge regarding the ability of phytocompounds to target phenotypic plasticity at both preclinical and clinical levels. Current challenges/pitfalls, limitations, and future perspectives are also discussed.

A comprehensive evaluation of the therapeutic potential of silibinin: a ray of hope in cancer treatment

Natural compounds hold promise in the search for cancer therapies due to their unique chemical structures and combinations that may effectively combat cancer while minimizing toxicity and side effects compared to conventional treatments. Silibinin, a natural lignan, has been found to possess strong anti-cancer activity against several types of human cancers based on emerging research. This study aims to provide an overview of the therapeutic potential of silibinin in the treatment and prevention of cancers. A comprehensive search was conducted using various internet databases such as PubMed, Google Scholar, and ScienceDirect to identify relevant research papers. Silibinin has been shown to exhibit anticancer activity against several types of cancers, including liver, lungs, breast, prostate, colorectal, skin, and bladder cancers. Its multifaceted mechanisms of action contribute to its therapeutic effects. Silibinin exerts antioxidant, anti-inflammatory, anti-proliferative, pro-apoptotic, anti-metastatic, and anti-angiogenic activities, making it a promising candidate for cancer therapy. One of the key mechanisms underlying the anticancer effects of silibinin is its ability to modulate multiple signaling pathways involved in cancer development and progression. It can inhibit the activation of various oncogenic pathways, including PI3K/Akt, NF-κB, Wnt/β-catenin, and MAPK pathways, thereby suppressing cancer cell proliferation, inducing cell cycle arrest, and promoting apoptosis. Silibinin possesses great potential as an effective treatment agent for cancer. The multifaceted mechanisms of action, favorable safety profile, and potential synergistic effects of silibinin with conventional therapies make it an attractive candidate for further investigation and development as a cancer treatment. However, more extensive clinical studies are necessary to fully establish the efficacy, optimal dosage, and long-term effects of silibinin in cancer treatment.

The role of flavonoids in the regulation of epithelial-mesenchymal transition in cancer: A review on targeting signaling pathways and metastasis

One of the hallmarks of cancer is metastasis, a process that entails the spread of cancer cells to distant regions in the body, culminating in tumor formation in secondary organs. Importantly, the proinflammatory environment surrounding cancer cells further contributes to cancer cell transformation and extracellular matrix destruction. During metastasis, front-rear polarity and emergence of migratory and invasive features are manifestations of epithelial-mesenchymal transition (EMT). A variety of transcription factors (TFs) are implicated in the execution of EMT, the most prominent belonging to the Snail Family Transcriptional Repressor (SNAI) and Zinc Finger E-Box Binding Homeobox (ZEB) families of TFs. These TFs are regulated by interaction with specific microRNAs (miRNAs), as miR34 and miR200. Among the several secondary metabolites produced in plants, flavonoids constitute a major group of bioactive molecules, with several described effects including antioxidant, antiinflammatory, antidiabetic, antiobesogenic, and anticancer effects. This review scrutinizes the modulatory role of flavonoids on the activity of SNAI/ZEB TFs and on their regulatory miRNAs, miR-34, and miR-200. The modulatory role of flavonoids can attenuate mesenchymal features and stimulate epithelial features, thereby inhibiting and reversing EMT. Moreover, this modulation is concomitant with the attenuation of signaling pathways involved in diverse processes as cell proliferation, cell growth, cell cycle progression, apoptosis inhibition, morphogenesis, cell fate, cell migration, cell polarity, and wound healing. The antimetastatic potential of these versatile compounds is emerging and represents an opportunity for the synthesis of more specific and potent agents.

A Narrative Review on CD44's Role in Glioblastoma Invasion, Proliferation, and Tumor Recurrence

High invasiveness is a characteristic of glioblastoma (GBM), making radical resection almost impossible, and thus, resulting in a tumor with inevitable recurrence. GBM recurrence may be caused by glioma stem-like cells (GSCs) that survive many kinds of therapy. GSCs with high expression levels of CD44 are highly invasive and resistant to radio-chemotherapy. CD44 is a multifunctional molecule that promotes the invasion and proliferation of tumor cells via various signaling pathways. Among these, paired pathways reciprocally activate invasion and proliferation under different hypoxic conditions. Severe hypoxia (0.5-2.5% O2) upregulates hypoxia-inducible factor (HIF)-1α, which then activates target genes, including CD44, TGF-β, and cMET, all of which are related to tumor migration and invasion. In contrast, moderate hypoxia (2.5-5% O2) upregulates HIF-2α, which activates target genes, such as vascular endothelial growth factor (VEGF)/VEGFR2, cMYC, and cyclin D1. All these genes are related to tumor proliferation. Oxygen environments around GBM can change before and after tumor resection. Before resection, the oxygen concentration at the tumor periphery is severely hypoxic. In the reparative stage after resection, the resection cavity shows moderate hypoxia. These observations suggest that upregulated CD44 under severe hypoxia may promote the migration and invasion of tumor cells. Conversely, when tumor resection leads to moderate hypoxia, upregulated HIF-2α activates HIF-2α target genes. The phenotypic transition regulated by CD44, leading to a dichotomy between invasion and proliferation according to hypoxic conditions, may play a crucial role in GBM recurrence.

Homeobox Gene Expression Dysregulation as Potential Diagnostic and Prognostic Biomarkers in Bladder Cancer

Homeobox genes serve as master regulatory transcription factors that regulate gene expression during embryogenesis. A homeobox gene may have either tumor-promoting or tumor-suppressive properties depending on the specific organ or cell lineage where it is expressed. The dysregulation of homeobox genes has been reported in various human cancers, including bladder cancer. The dysregulated expression of homeobox genes has been associated with bladder cancer clinical outcomes. Although bladder cancer has high risk of tumor recurrence and progression, it is highly challenging for clinicians to accurately predict the risk of tumor recurrence and progression at the initial point of diagnosis. Cystoscopy is the routine surveillance method used to detect tumor recurrence. However, the procedure causes significant discomfort and pain that results in poor surveillance follow-up amongst patients. Therefore, the development of reliable non-invasive biomarkers for the early detection and monitoring of bladder cancer is crucial. This review provides a comprehensive overview of the diagnostic and prognostic potential of homeobox gene expression dysregulation in bladder cancer.

New insight in urological cancer therapy: From epithelial-mesenchymal transition (EMT) to application of nano-biomaterials

A high number of cancer-related deaths (up to 90) are due to metastasis and simple definition of metastasis is new colony formation of tumor cells in a secondary site. In tumor cells, epithelial-mesenchymal transition (EMT) stimulates metastasis and invasion, and it is a common characteristic of malignant tumors. Prostate cancer, bladder cancer and renal cancer are three main types of urological tumors that their malignant and aggressive behaviors are due to abnormal proliferation and metastasis. EMT has been well-documented as a mechanism for promoting invasion of tumor cells and in the current review, a special attention is directed towards understanding role of EMT in malignancy, metastasis and therapy response of urological cancers. The invasion and metastatic characteristics of urological tumors enhance due to EMT induction and this is essential for ensuring survival and ability in developing new colonies in neighboring and distant tissues and organs. When EMT induction occurs, malignant behavior of tumor cells enhances and their tend in developing therapy resistance especially chemoresistance promotes that is one of the underlying reasons for therapy failure and patient death. The lncRNAs, microRNAs, eIF5A2, Notch-4 and hypoxia are among common modulators of EMT mechanism in urological tumors. Moreover, anti-tumor compounds such as metformin can be utilized in suppressing malignancy of urological tumors. Besides, genes and epigenetic factors modulating EMT mechanism can be therapeutically targeted for interfering malignancy of urological tumors. Nanomaterials are new emerging agents in urological cancer therapy that they can improve potential of current therapeutics by their targeted delivery to tumor site. The important hallmarks of urological cancers including growth, invasion and angiogenesis can be suppressed by cargo-loaded nanomaterials. Moreover, nanomaterials can improve chemotherapy potential in urological cancer elimination and by providing phototherapy, they mediate synergistic tumor suppression. The clinical application depends on development of biocompatible nanomaterials.

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

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

Flavonoids target different molecules of autophagic and metastatic pathways in cancer cells

Despite the success of cancer therapy, it has encountered a major obstacle due to the complicated nature of cancer, namely resistance. The recurrence and metastasis of cancer occur when anti-cancer therapeutic agents fail to eradicate all cancer cells. Cancer therapy aims to find the best agent that targets all cancer cells, including those sensitive or resistant to treatment. Flavonoids, natural products from our diet, show anti-cancer effects in different studies. They can inhibit metastasis and the recurrence of cancers. This review discusses metastasis, autophagy, anoikis in cancer cells, and their dynamic relationship. We present evidence that flavonoids can block metastasis and induce cell death in cancer cells. Our research suggests that flavonoids can serve as potential therapeutic agents in cancer therapy.

CD44 Promotes Breast Cancer Metastasis through AKT-Mediated Downregulation of Nuclear FOXA2

The primary cause of breast cancer mortality is the metastatic invasion of cancerous stem cells (CSC). Cluster of differentiation 44 (CD44) is a well-known CSC marker in various cancers, as well as a key role player in metastasis and relapse of breast cancer. CD44 is a cell-membrane embedded protein, and it interacts with different proteins to regulate cancer cell behavior. Transcription factor forkhead box protein A2 (FOXA2) acts as an important regulator in multiple cancers, including breast cancer. However, the biological significance of CD44-FOXA2 association in breast cancer metastasis remains unclear. Herein, we observed that CD44 expression was higher in metastatic lymph nodes compared to primary tumors using a flow cytometric analysis. CD44 overexpression in breast cancer cell lines significantly promoted cell migration and invasion abilities, whereas the opposite effects occurred upon the knockdown of CD44. The stem cell array analysis revealed that FOXA2 expression was upregulated in CD44 knockdown cells. However, the knockdown of FOXA2 in CD44 knockdown cells reversed the effects on cell migration and invasion. Furthermore, we found that CD44 mediated FOXA2 localization in breast cancer cells through the AKT pathway. Moreover, the immunofluorescence assay demonstrated that AKT inhibitor wortmannin and AKT activator SC79 treatment in breast cancer cells impacted FOXA2 localization. Collectively, this study highlights that CD44 promotes breast cancer metastasis by downregulating nuclear FOXA2.

Silibinin exhibits anti-tumor effects in a breast cancer stem cell model by targeting stemness and induction of differentiation and apoptosis

Introduction: Malignant breast cancer (BC) frequently contains a rare population of cells called cancer stem cells which underlie tumor relapse and metastasis, and targeting these cells may improve treatment options and outcomes for patients with BC. The aim of the present study was to determine the effect of silibinin on the self-renewal capacity, tumorgenicity, and metastatic potential of mammospheres. Methods: The effect of silibinin on viability and proliferation of MCF-7, MDA-MB-231 mammospheres, and MDA-MB-468 cell aggregation was determined after 72-120 hours of treatment. Colony and sphere formation ability, and the expression of stemness, differentiation, and epithelial-mesenchymal-transition (EMT)-associated genes were assessed by reverse transcription-quantitative polymerase chain reaction (qRT-PCR) in mammospheres treated with an IC₅₀ dose of silibinin. Additionally, the antitumor capacity of silibinin was assessed in vivo, in mice. Results: The results of the present study showed that silibinin decreased the viability of all mammospheres derived from MCF-7, MDA-MB-231, and MDA-MB-468 cell aggregation in a dose-dependent manner. Colony and sphere-forming ability, as well as the expression of genes associated with EMT were reduced in mammospheres treated with silibinin. Additionally, the expression of genes associated with stemness and metastasis was also decreased and the expression of genes associated with differentiation were increased. Intra-tumoral injection of 2 mg/kg silibinin decreased tumor volumes in mice by 2.8 fold. Conclusion: The present study demonstrated that silibinin may have exerted its anti-tumor effects in BC by targeting the BC stem cells, reducing the tumorgenicity and metastasis. Therefore, silibinin may be a potential adjuvant for treatment of BC.

Role of Silymarin in Cancer Treatment: Facts, Hypotheses, and Questions

The flavonoid silymarin extracted from the seeds of Sylibum marianum is a mixture of 6 flavolignan isomers. The 3 more important isomers are silybin (or silibinin), silydianin, and silychristin. Silybin is functionally the most active of these compounds. This group of flavonoids has been extensively studied and they have been used as hepato-protective substances for the mushroom Amanita phalloides intoxication and mainly chronic liver diseases such as alcoholic cirrhosis and nonalcoholic fatty liver. Hepatitis C progression is not, or slightly, modified by silymarin. Recently, it has also been proposed for SARS COVID-19 infection therapy. The biochemical and molecular mechanisms of action of these substances in cancer are subjects of ongoing research. Paradoxically, many of its identified actions such as antioxidant, promoter of ribosomal synthesis, and mitochondrial membrane stabilization, may seem protumoral at first sight, however, silymarin compounds have clear anticancer effects. Some of them are: decreasing migration through multiple targeting, decreasing hypoxia inducible factor-1α expression, inducing apoptosis in some malignant cells, and inhibiting promitotic signaling among others. Interestingly, the antitumoral activity of silymarin compounds is limited to malignant cells while the nonmalignant cells seem not to be affected. Furthermore, there is a long history of silymarin use in human diseases without toxicity after prolonged administration. The ample distribution and easy accessibility to milk thistle-the source of silymarin compounds, its over the counter availability, the fact that it is a weed, some controversial issues regarding bioavailability, and being a nutraceutical rather than a drug, has somehow led medical professionals to view its anticancer effects with skepticism. This is a fundamental reason why it never achieved bedside status in cancer treatment. However, in spite of all the antitumoral effects, silymarin actually has dual effects and in some cases such as pancreatic cancer it can promote stemness. This review deals with recent investigations to elucidate the molecular actions of this flavonoid in cancer, and to consider the possibility of repurposing it. Particular attention is dedicated to silymarin's dual role in cancer and to some controversies of its real effectiveness.

Knockdown of CXCL5 inhibits the invasion, metastasis and stemness of bladder cancer lung metastatic cells by downregulating CD44

In our previous studies, we found that T24 lung metastatic cancer cells showed high invasion and metastasis abilities and cancer stem cell characteristics compared with T24 primary cancer cells. By screening for the expression of CXC chemokines in both cell lines, we found that CXCL5 is highly expressed in T24-L cells. The aim of this study is to shed light on the relationship of CXCL5 with epithelial-mesenchymal transition (EMT) and cancer stem cells (CSCs). RNAi technology was used to decrease CXCL5 expression in the T24-L cell line, and the EMT and CSCs of the shCXCL5 group and the control group were compared. The CXCR2 inhibitor SB225002 was used to inhibit the receptor of CXCL5 to determine the effect of the CXCL5/CXCR2 axis. The knockdown of CXCL5 expression in T24-L cells reduced their EMT and CSC characteristics. RT-PCR and Western blot analyses revealed the downregulation of N-cadherin, Vimentin and CD44. In addition, when CD44 expression was knocked down, the EMT ability of the cells was also inhibited. This phenomenon was most pronounced when both CXCL5 and CD44 were knocked down. CXCL5 and CD44 can affect the EMT and stem cell capacity of T24-L cells through some interaction.

Wnt/β-Catenin Signaling Contributes to Paclitaxel Resistance in Bladder Cancer Cells with Cancer Stem Cell-Like Properties

The Wnt/β-catenin pathway plays an important role in tumor progression and chemotherapy resistance and seems to be essential for the maintenance of cancer stem cells (CSC) in several tumor types. However, the interplay of these factors has not been fully addressed in bladder cancer. Here, our goal was to analyze the role of the Wnt/β-catenin pathway in paclitaxel resistance and to study the therapeutic efficacy of its inhibition in bladder cancer cells, as well as to determine its influence in the maintenance of the CSC-like phenotype in bladder cancer. Our results show that paclitaxel-resistant HT1197 cells have hyperactivation of the Wnt/β-catenin pathway and increased CSC-like properties compared with paclitaxel-sensitive 5637 cells. Paclitaxel sensitivity diminishes in 5637 cells after β-catenin overexpression or when they are grown as tumorspheres, enriched for the CSC-like phenotype. Additionally, downregulation of β-catenin or inhibition with XAV939 sensitizes HT1197 cells to paclitaxel. Moreover, a subset of muscle-invasive bladder carcinomas shows aberrant expression of β-catenin that associates with positive expression of the CSC marker ALDH1A1. In conclusion, we demonstrate that Wnt/β-catenin signaling contributes to paclitaxel resistance in bladder cancer cells with CSC-like properties.

WNT7B represses epithelial-mesenchymal transition and stem-like properties in bladder urothelial carcinoma

BACKGROUND

Recurrence and metastasis are the major problems of bladder urothelial carcinoma, which mainly attribute to tumor cell stemness, epithelial-mesenchymal transition (EMT) and chemoresistance.

METHODS

TCGA database was interrogated for gene mRNA expression in bladder urothelial carcinoma samples. CCLE database was interrogated for gene mRNA expression in bladder cancer cell lines. The correlation between two genes was analyzed by Pearson statistics. 37 human bladder urothelial carcinoma specimens were adopted for immunohistochemistry. Bladder cancer cells RT4, J82, and UM-UC-3 were used to carry out loss and gain of function studies. Kaplan-Meier method was performed to analyze the overall survival.

FINDINGS

WNT7B is downregulated in high-grade bladder urothelial carcinomas. Low WNT7B expression is associated with unfavorable prognosis. Loss and gain of function studies showed that WNT7B inhibits bladder urothelial carcinoma cell EMT, stem-like properties and chemoresistance. FZD5, a specific receptor for WNT7B, mediates WNT7B signaling. ELF3 is a downstream component of WNT7B signaling, which transcriptionally modulates NOTCH1, a tumor suppressor in bladder urothelial carcinoma.

INTERPRETATION

These data demonstrate that WNT7B/FZD5-ELF3-NOTCH1 signaling functions as a tumor-suppressing pathway in bladder urothelial carcinoma.

Silibinin Regulates Tumor Progression and Tumorsphere Formation by Suppressing PD-L1 Expression in Non-Small Cell Lung Cancer (NSCLC) Cells

Recently, natural compounds have been used globally for cancer treatment studies. Silibinin is a natural compound extracted from Silybum marianum (milk thistle), which has been suggested as an anticancer drug through various studies. Studies on its activity in various cancers are undergoing. This study demonstrated the molecular signaling behind the anticancer activity of silibinin in non-small cell lung cancer (NSCLC). Quantitative real-time polymerase chain reaction and Western blotting analysis were performed for molecular signaling analysis. Wound healing assay, invasion assay, and in vitro angiogenesis were performed for the anticancer activity of silibinin. The results indicated that silibinin inhibited A549, H292, and H460 cell proliferation in a concentration-dependent manner, as confirmed by the induction of G0/G1 cell cycle arrest and apoptosis and the inhibition of tumor angiogenesis, migration, and invasion. This study also assessed the role of silibinin in suppressing tumorsphere formation using the tumorsphere formation assay. By binding to the epidermal growth factor receptor (EGFR), silibinin downregulated phosphorylated EGFR expression, which then inhibited its downstream targets, the JAK2/STAT5 and PI3K/AKT pathways, and thereby reduced matrix metalloproteinase, PD-L1, and vascular endothelial growth factor expression. Binding analysis demonstrated that STAT5 binds to the PD-L1 promoter region in the nucleus and silibinin inhibited the STAT5/PD-L1 complex. Altogether, silibinin could be considered as a candidate for tumor immunotherapy and cancer stem cell-targeted therapy.

Evaluation of anti-cancer potency of silibinin on murine renal carcinoma RenCa cells in an animal model with an intact immune system

Silibinin is a flavonoid extract isolated from milk thistle and has been proved to be a promising chemotherapeutic drug for cancer. However, most of those studies were performed on the human cancer cells, where the effects of silibinin could only be observed on an animal model with a deficient immune system. RenCa cells were isolated from a murine spontaneous renal cell carcinoma, which resembles many features of human renal cell carcinoma, and have been used to establish animal models with a sound immune response. Herein, we investigated the anti-cancer effects of silibinin on RenCa cells, revealing that it inhibited cell viability in both dose- and time-dependent manners. Silibinin slightly triggered apoptosis and significantly induced G2-M cell cycle arrest by downregulating cyclin B1 and CDK1 and increasing expression of p21. Furthermore, silibinin significantly inhibited the growth of RenCa cell xenografts in vivo. In addition, we found that silibinin reduced programmed cell death 1 ligand 1 expression of RenCa cells in vivo and in vitro. Our findings demonstrate that silibinin can inhibit the growth of mouse tumor cells in an animal model with an intact immune system, and silibinin may decrease the immunosuppression effect of tumor cells. Our results provide new evidence for evaluation of Silibinin application in cancer therapy.

Role of the interactions of soft hyaluronan nanomaterials with CD44 and supported bilayer membranes in the cellular uptake

Increasing valence by acting on nanomaterial morphology can enhance the ability of a ligand to specifically bind to targeted cells. Herein, we investigated cell internalization of soft hyaluronic acid (HA) nanoplatelets (NPs) that exhibit a typical hexagonal shape, flat surfaces and high aspect ratio (Γ≈12 to 20), as characterized by atomic force microscopy in hydrated conditions. Fluorescence imaging revealed that internalization of HA-NPs by a T24 tumor cell line and by macrophages was higher than native polysaccharide in a dose-dependent and time-dependent manners. The ability of HA-NPs to efficiently compete with native HA assessed using Bio-layer interferometry showed that NPs had a stronger interaction with recombinant CD44 receptor compared to native HA. The results were discussed regarding physical properties of the NPs and the implication of multivalent interactions in HA binding to CD44. Experiments conducted on supported bilayer membranes with different compositions showed that non-specific interactions of NPs with lipid membranes were negligible. Our findings provide insights into intracellular drug delivery using soft HA-NPs through receptor-mediated multivalent interactions.

The role of CD44 in cancer chemoresistance: A concise review

CD44 is a cell surface adhesion molecule, which is overexpressed on cancer stem cells. The interaction of CD44 with hyaluronan is responsible for tumor development, metastasis, and expression of the chemoresistant phenotype. The overexpression of CD44 impedes the cytotoxic effect of chemotherapy medications in various cancers. Therefore, the high expression of CD44 is associated with a poor prognosis in affected patients. This high expression of CD44 in various cancers has provided an ample opportunity for the treatment of patients with chemoresistant malignancy. This review aims to demonstrate the various cross-talk between CD44 and intracellular and extracellular factors and highlight its role in developing chemoresistant tumors in some troublesome cancers.

MUC15 loss facilitates epithelial-mesenchymal transition and cancer stemness for prostate cancer metastasis through GSK3β/β-catenin signaling

Patients with prostate cancer (PCa) have a high incidence of relapse and metastasis. Unfortunately, the molecular mechanisms underlying these processes have not been fully elucidated. In our study, we demonstrate that MUC15, a member of the mucin family, is a novel tumor suppressor in PCa that modulates epithelial-mesenchymal transition (EMT) and cancer stemness, contributing to PCa metastasis. First, MUC15 expression was found to be decreased in PCa tissues compared with para-carcinoma tissues. Moreover, we observed that MUC15 suppressed cell migration and invasion, both in vitro and in vivo, but had no effect on cell proliferation. Mechanistically, knockdown of MUC15 increased GSK3β phosphorylation and promoted β-catenin nuclear translocation. Therefore, the β-catenin-specific inhibitors XAV939 and PRI-724 rescued EMT in MUC15-deficient cell lines. Taken together, these results indicate that MUC15 is downregulated in PCa tissues and serves as a potential target to prevent PCa metastasis, which can inhibit EMT and cancer stemness via the GSK3β/β-catenin signaling pathway.

ITPR3 facilitates tumor growth, metastasis and stemness by inducing the NF-ĸB/CD44 pathway in urinary bladder carcinoma

Background

Bladder carcinoma is one of the most common urological cancers. ITPR3, as a ubiquitous endoplasmic reticulum calcium channel protein, was reported to be involved in the development and progression of various types of cancer. However, the potential roles and molecular mechanism of ITPR3 in bladder cancer are still unclear. Herein, we elucidated a novel role of ITPR3 in regulating the proliferation, metastasis, and stemness of bladder cancer cells.

Methods

The expression of ITPR3 in bladder cancer was analyzed using public databases and bladder cancer tissue microarrays. To demonstrate the role of ITPR3 in regulating the NF-ĸB/CD44 pathway and the progression of bladder cancer, a series of molecular biology and biochemistry methods was performed on clinical tissues, along with in vivo and in vitro experiments. The methods used included western blot assay, quantitative RT-PCR assay, immunofluorescence assay, immunohistochemistry (IHC) assays, wound healing assay, Transwell assay, colony formation assay, tumorsphere formation assay, cell flow cytometry analysis, EdU assay, MTT assay, cell transfection, bisulfite sequencing PCR (BSP), a xenograft tumor model and a tail vein cancer metastasis model.

Results

Higher ITPR3 expression was found in bladder cancer tissues and bladder cancer cells compared with the corresponding normal peritumor tissues and SV-HUC-1 cells, which was attributed to demethylation in the ITPR3 promoter region. ITPR3 promoted the proliferation of bladder cancer by accelerating cell cycle transformation and promoted local invasion and distant metastasis by inducing epithelial-to-mesenchymal transition (EMT). Meanwhile, ITPR3 maintained the cancer stemness phenotype by regulating CD44 expression. NF-κB, which is upstream of CD44, also played a critical role in this process.

Conclusions

Our study clarifies that ITPR3 serves as an oncogene in bladder cancer cells and represents a novel candidate for bladder cancer diagnosis and treatment.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13046-021-01866-1.

Transcriptome profiling reveals Silibinin dose-dependent response network in non-small lung cancer cells

Silibinin (SIL), a natural flavonolignan from the milk thistle (Silybum marianum), is known to exhibit remarkable hepatoprotective, antineoplastic and EMT inhibiting effects in different cancer cells by targeting multiple molecular targets and pathways. However, the predominant majority of previous studies investigated effects of this phytocompound in a one particular cell line. Here, we carry out a systematic analysis of dose-dependent viability response to SIL in five non-small cell lung cancer (NSCLC) lines that gradually differ with respect to their intrinsic EMT stage. By correlating gene expression profiles of NSCLC cell lines with the pattern of their SIL IC50 response, a group of cell cycle, survival and stress responsive genes, including some prominent targets of STAT3 (BIRC5, FOXM1, BRCA1), was identified. The relevancy of these computationally selected genes to SIL viability response of NSCLC cells was confirmed by the transient knockdown test. In contrast to other EMT-inhibiting compounds, no correlation between the SIL IC50 and the intrinsic EMT stage of NSCLC cells was observed. Our experimental results show that SIL viability response of differently constituted NSCLC cells is linked to a subnetwork of tightly interconnected genes whose transcriptomic pattern can be used as a benchmark for assessment of individual SIL sensitivity instead of the conventional EMT signature. Insights gained in this study pave the way for optimization of customized adjuvant therapy of malignancies using Silibinin.

Targeted Delivery of Therapeutics to Urological Cancer Stem Cells

Urological cancer refers to cancer in organs of the urinary system and the male reproductive system. It mainly includes prostate cancer, bladder cancer, renal cancer, etc., seriously threatening patients' survival. Although there are many advances in the treatment of urological cancer, approved targeted therapies often result in tumor recurrence and therapy failure. An increasing amount of evidence indicated that cancer stem cells (CSCs) with tumor-initiating ability were the source of treatment failure in urological cancer. The development of CSCstargeted strategy can provide a possibility for the complete elimination of urological cancer. This review is based on a search of PubMed, Google scholar and NIH database (http://ClinicalTrials.gov/) for English language articles containing the terms: "biomarkers", "cancer stem cells", "targeting/targeted therapy", "prostate cancer", bladder cancer" and "kidney cancer". We summarized the biomarkers and stem cell features of the prostate, bladder and renal CSCs, outlined the targeted strategies for urological CSCs from signaling pathways, cytokines, angiogenesis, surface markers, elimination therapy, differentiation therapy, immunotherapy, microRNA, nanomedicine, etc., and highlighted the prospects and future challenges in this research field.

Knockdown of lncRNA ZNRD1-AS1 inhibits progression of bladder cancer by regulating miR-194 and ZEB1

BACKGROUND

Bladder cancer (BC) is a common urinary neoplasm with high incidence worldwide. Long noncoding RNA zinc ribbon domain containing 1 antisense RNA 1 (ZNRD1-AS1) has been reported to be upregulated in BC. However, the exact role of ZNRD1-AS1 as well as its mechanism remains poorly understood.

METHODS

Zinc ribbon domain containing 1 antisense RNA 1, and its potential downstream genes microRNA-194 (miR-194) and zinc finger E-box binding homeobox 1 (ZEB1) levels were detected via quantitative real-time polymerase chain reaction or western blot. Cell proliferation, migration, invasion, and epithelial-mesenchymal transition (EMT) were detected to assess the influences of ZNRD1-AS1, miR-194 and ZEB1 on BC cells by colony formation, cell counting kit-8 (CCK-8), transwell analysis or western blot. The relationship between miR-194 and ZNRD1-AS1 or ZEB1 was analyzed by luciferase activity analysis. The xenograft experiment was performed to assess the function of ZNRD1-AS1 in vivo.

RESULTS

Zinc ribbon domain containing 1 antisense RNA 1level was upregulated in BC. ZNRD1-AS1 silence repressed proliferation, migration, invasion and EMT in BC cells. MiR-194 was identified as a target of ZNRD1-AS1, and miR-194 upregulation repressed proliferation, migration, invasion, and EMT by ZNRD1-AS1 sponging. ZEB1 was targeted via miR-194 and its interference impeded proliferation, migration, invasion, and EMT. Moreover, ZNRD1-AS1 regulated ZEB1 expression via miR-194. Besides, inhibition of ZNRD1-AS1 attenuated tumor growth by miR-194/ZEB1 axis in vivo.

CONCLUSION

Knockdown of ZNRD1-AS1 suppressed BC cell development in vitro and in vivo via targeting miR-194 to regulate ZEB1, indicating a novel avenue for treatment of BC.

Cancer stem cells and nanomedicine: new opportunities to combat multidrug resistance?

'Multidrug resistance' (MDR) is a difficult challenge for cancer treatment. The combined role of cytochrome P450 enzymes (CYPs) and active efflux transporters (AETs) in cancer cells appears relevant in inducing MDR. Chemotherapeutic drugs can be substrates of both CYPs and AETs and CYP inducers or inhibitors can produce the same effects on AETs. In addition, a small subpopulation of cancer stem-like cells (CSCs) appears to survive conventional chemotherapy, leading to recurrent disease. Natural products appear efficacious against CSCs; their combinational treatments with standard chemotherapy are promising for cancer eradication, in particular when supported by nanotechnologies.

Cancer Chemopreventive Activities of Silibinin on Colorectal Cancer through Regulation of E-Cadherin/β-Catenin Pathway

PURPOSE

Silibinin is the most active flavonolignan constituent of Silymarin, the extract of milk thistle seeds. In this study, we investigated the anticancer properties and molecular mechanisms of silibinin on colorectal cancer (CRC) cells.

METHODS

HCT-116 cells were used to investigate the effects of silibinin on proliferation, migration, epithelial-mesenchymal transition (EMT), cancer stem cells (CSCs), apoptosis and signaling pathways underlying these functions by using 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and colony formation assay, quantitative reverse-transcription polymerase chain reaction (RT-qPCR), Western blot, Acridine orange/propidium iodide double staining, migration and sphere formation assay.

RESULTS

Silibinin significantly suppressed HCT-116 cells proliferation and migration and induced the apoptosis via increasing the Bax/Bcl-2 ratio. Silibinin down-regulated cancer stemness markers; prominin-1 (CD133), CD44, BMI1, Aldehyde dehydrogenase 1 (ALDH1), and doublecortin-like kinase 1 (DCLK1) of HCT-116 cell line. Silibinin attenuated EMT through decreased expression of N- cadherin and vimentin and increased expression of (E-cadherin). Furthermore, silibinin decreased the β-catenin gene and protein expression.

CONCLUSION

Our study revealed that silibinin maintains various antitumor activities such as induction of apoptosis, suppression of migration, elimination of CSCs and attenuation of EMT related markers in CRC cells. These underlying anti-tumor mechanisms of silibinin are likely to act through the blockage of the β-catenin signaling pathway, which is the key component of Wnt signaling pathway, one of the hallmarks of CRC development.

The protoapigenone analog WYC0209 targets CD133+ cells: A potential adjuvant agent against cancer stem cells in urothelial cancer therapy

Urothelial carcinoma (UC) is one of the highest incidence cancers that rank the fourth commonly diagnosed tumors worldwide. The unresectable lesions that are resistant to therapeutic interventions is the major cause leading to death. Previous studies had shown that the resistance and metastatic consequence may arise from cancer stem-like cells population. The phytochemical flavonoids have promised bioactivity and potent anti-carcinogenic effects, and trap great attentions for cancer chemoprevention and/or adjuvant chemotherapy. However, the mechanisms of flavonoids on cancer stemness is still obscured. In this study, we analyzed the biofunctional effects of as-prepared flavonoid derivative-WYC0209 on T24, BFTC905 and BFTC909 human UC cell lines. Our results demonstrated that WYC0209 significantly induced anti-cell viability on UC cells through decreased Akt/NFkB signaling. Moreover, WYC0209 enhanced the cell apoptosis through activated the caspase-3 activity and inactivated Bcl-xL expression. Interestingly, WYC0209 dramatically inhibited the cancer stem cells (CSCs) traits, including attenuation of side population and tumorsphere formation in which were through declined EMT-CSCs markers including MDR1, ABCG2 and BMI-1. We further validated the effects of WYC0209 on several CSC surface markers including CD133, CD44, SOX-2 and Nanog. Our results showed that WYC0209 markedly inhibited CD133 expressions in both transcriptional and translational levels. High expression levels of CD133 was also demonstrated in human upper tract UC specimens. In summary, our study showed that WYC0209 may potentially as an adjuvant agent to against CD133-driven UC CSCs and provide a beneficial strategy to against UC cancer therapeutics resistant.

Silibinin suppresses epithelial-mesenchymal transition in human non-small cell lung cancer cells by restraining RHBDD1

Background

Rhomboid domain containing 1 (RHBDD1) plays a crucial role in tumorigenesis. Silibinin, which is a natural extract from milk thistle, has shown anti-tumor effects against various tumors. Here, we investigate whether silibinin affects the function of RHBDD1 in non-small cell lung cancer (NSCLC) cell proliferation, migration and invasion.

Methods

The Oncomine database and an immunohistochemistry (IHC) assay were used to determine the RHBDD1 expression levels in lung cancer tissues. The associations between RHBDD1 and overall survival rate or clinicopathological parameters were respectively assessed using the Kaplan-Meier overall survival analysis or Chi-squared test. CCK-8 and Transwell assays were applied to analyze cell proliferation, migration and invasion. A549 cells were incubated with increasing concentrations of silibinin. RHBDD1 knockdown and overexpression were achieved via transfection with si-RHBDD1 or RHBDD1 overexpression plasmid, respectively. Western blotting was performed to measure the expressions of epithelial–mesenchymal transition (EMT) markers.

Results

We found that overexpression of RHBDD1 in lung cancer tissues correlates with a poor prognosis of survival. Clinical specimen analysis showed that upregulation of RHBDD1 correlates remarkably well with TNM stage and lymph node metastasis. Silibinin suppresses A549 cell proliferation, migration, invasion and EMT in a dose-dependent manner. Importantly, RHBDD1 was downregulated in silibinin-treated A549 cells. RHBDD1 overexpression reversed the suppressive effects of silibinin on A549 cell proliferation, migration, invasion and EMT expression, while its knockdown enhanced them.

Conclusions

These findings shown an anti-tumor impact of silibinin on NSCLC cells via repression of RHBDD1.

Putting the Brakes on Tumorigenesis with Natural Products of Plant Origin: Insights into the Molecular Mechanisms of Actions and Immune Targets for Bladder Cancer Treatment

Bladder cancer is the 10th most commonly diagnosed cancer worldwide. Although the incidence in men is 4 times higher than that in women, the diagnoses are worse for women. Over the past 30 years, the treatment for bladder cancer has not achieved a significant positive effect, and the outlook for mortality rates due to muscle-invasive bladder cancer and metastatic disease is not optimistic. Phytochemicals found in plants and their derivatives present promising possibilities for cancer therapy with improved treatment effects and reduced toxicity. In this study, we summarize the promising natural products of plant origin with anti-bladder cancer potential, and their anticancer mechanisms—especially apoptotic induction—are discussed. With the developments in immunotherapy, small-molecule targeted immunotherapy has been promoted as a satisfactory approach, and the discovery of novel small molecules against immune targets for bladder cancer treatment from products of plant origin represents a promising avenue of research. It is our hope that this could pave the way for new ideas in the fields of oncology, immunology, phytochemistry, and cell biology, utilizing natural products of plant origin as promising drugs for bladder cancer treatment.

MUC15 inhibits cancer metastasis via PI3K/AKT signaling in renal cell carcinoma

Patients with renal cell carcinoma (RCC) often develop distant metastasis and the specific molecular mechanism remains poorly understood. In our study, we demonstrated that MUC15, a subtype of mucins family, could suppress the progression of RCC by inhibiting PI3K/AKT signaling. Firstly, we observed that MUC15 was notably decreased in RCC compared to normal tissue. Furthermore, we showed that MUC15 could negatively modulate the migration and invasion of RCC in vitro and in vivo. Mechanistically, we found that knocking-down of MUC15 could active the PI3K/AKT signaling by increasing the AKT phosphorylation and subsequently increase the mRNA and protein expression of MMP2 and MMP9. Interruption of the AKT pathway with the specific inhibitor LY294002 could reverse the expression of MMPs. Therefore, our study clarify the novel function of MUC15 in RCC, which may provide a new sight to diagnose and prevent RCC metastasis.

Silibinin inhibits epithelial‑mesenchymal transition of renal cell carcinoma through autophagy‑dependent Wnt/β‑catenin signaling

Silibinin is a flavonoid extracted from milk thistle seeds which has been widely used as a hepatoprotective and antioxidant agent. Recently, accumulating evidence has demonstrated the anti-cancer effects of silibinin in various cancer models. It was previously reported that silibinin induced apoptosis and decreased metastasis by activating autophagy in renal cell carcinoma (RCC). However, the underlying molecular mechanisms by which silibinin regulates autophagy remain largely unknown. The aim of the present study was to investigate the effects of silibinin on RCC metastasis in vitro and in vivo, with a focus on autophagy-dependent Wnt/β-catenin signaling. Human RCC 786-O and ACHN cell lines were used as the model system in vitro and RCC xenografts of nude mice were used for in vivo studies. Silibinin inhibited metastasis and epithelial-mesenchymal transition (EMT) of RCC in vitro and in vivo, by regulating the Wnt/β-catenin signaling pathway. Furthermore, silibinin inhibited the Wnt/β-catenin signaling pathway in an autophagy-dependent manner. Autophagic degradation of β-catenin induced by silibinin was associated with the anti-metastatic effects of silibinin against RCC. These findings identify a novel mechanism by which silibinin inhibits EMT and metastasis of RCC, highlighting a potential novel strategy for treating metastatic RCC.

Isorhapontigenin (ISO) inhibits stem cell-like properties and invasion of bladder cancer cell by attenuating CD44 expression

Cancer stem cells (CSC) are highly associated with poor prognosis in cancer patients. Our previous studies report that isorhapontigenin (ISO) down-regulates SOX2-mediated cyclin D1 induction and stem-like cell properties in glioma stem-like cells. The present study revealed that ISO could inhibit stem cell-like phenotypes and invasivity of human bladder cancer (BC) by specific attenuation of expression of CD44 but not SOX-2, at both the protein transcription and degradation levels. On one hand, ISO inhibited cd44 mRNA expression through decreases in Sp1 direct binding to its promoter region-binding site, resulting in attenuation of its transcription. On the other hand, ISO also down-regulated USP28 expression, which in turn reduced CD44 protein stability. Further studies showed that ISO treatment induced miR-4295, which specific bound to 3'-UTR activity of usp28 mRNA and inhibited its translation and expression, while miR-4295 induction was mediated by increased Dicer protein to enhance miR-4295 maturation upon ISO treatment. Our results provide the first evidence that ISO has a profound inhibitory effect on human BC stem cell-like phenotypes and invasivity through the mechanisms distinct from those previously noted in glioma stem-like cells.

Involvement of hyaluronan and CD44 in cancer and viral infections

Hyaluronan and its major receptor CD44 are ubiquitously distributed. They have important structural as well as signaling roles, regulating tissue homeostasis, and their expression levels are tightly regulated. In addition to signaling initiated by the interaction of the intracellular domain of CD44 with cytoplasmic signaling molecules, CD44 has important roles as a co-receptor for different types of receptors of growth factors and cytokines. Dysregulation of hyaluronan-CD44 interactions is seen in diseases, such as inflammation and cancer. In the present communication, we discuss the mechanism of hyaluronan-induced signaling via CD44, as well as the involvement of hyaluronan-engaged CD44 in malignancies and in viral infections.

WNT/β-catenin signaling in urothelial carcinoma of bladder

Urothelial carcinoma of bladder is the second most prevalent genitourinary disease. It is a highly heterogeneous disease as it represents a spectrum of neoplasms, including non-muscle invasive bladder cancer (NMIBC), muscle invasive bladder cancer (MIBC) and metastatic lesions. Genome-wide approaches and candidate gene analysis suggest that malignant transformation of the bladder is multifactorial and a multitude of genes are involved in the development of MIBC or NMIBC phenotypes. Wnt signaling is being examined to control and maintain balance between stemness and differentiation in adult stem cell niches. Owing to its participation in urothelial development and maintenance of adult urothelial tissue homeostasis, the components of Wnt signaling are reported as an important diagnostic and prognostic markers as well as novel therapeutic targets. Mutations/epigenetic alterations in the key molecules of Wnt/β-catenin canonical pathway have been linked with tumorigenesis, development of drug resistance and enhanced survival. Present review extends our understanding on the functions of key regulatory molecules of canonical Wnt/β-catenin pathway in urothelial tumorigenesis by inducing cancer stem cell phenotype (UCSCs). UCSCs may be responsible for tumor heterogeneity, high recurrence rates and complex biological behavior of bladder cancer. Therefore, understanding the role of UCSCs and the regulatory mechanisms that are responsible for high relapse rates and metastasis could help to develop pathway inhibitors and augment current therapies. Potential implications in the treatment of urothelial carcinoma of bladder by targeting this pathway primarily in UCSCs as well as in bulk tumor population that are responsible for high relapse rates and metastasis may facilitate potential therapeutic avenues and better prognosis.

Silencing of CARMA3 inhibits bladder cancer cell migration and invasion via deactivating β-catenin signaling pathway

Background

Bladder cancer (BC) is the ninth most common cancer and the fourteenth leading death worldwide. CARD-containing MAGUK 3 (CARMA3) protein is a novel scaffold protein known to activate NF-κB pathway and is overexpressed in BC tissues.

Purpose

The objective of this study was to identify how CARMA3 affects the metastasis of BC cells via the β-catenin signaling pathway.

Materials and methods

In the present study, 5637 and T24 BC cells with stable low expression of CARMA3 were established, and their migratory and invasive capabilities were further evaluated by wound-healing and transwell assay. The activity and expression of β-catenin were determined by Luciferase assay and immunofluoresence staining. The mRNA and protein expression levels of CARMA3, matrix metallopeptidase (MMP) 9 and MMP2 were detected by quantitative real-time PCR (qRT-PCR) and Western blot analysis. The nude mouse tumor xenograft model was established for in vivo study.

Results

By comparison to the control cells, CARMA3-silenced cells acquired a less aggressive phenotype: decreased migration and invasion. More importantly, we confirmed that CARM3 knockdown could inhibit β-catenin mRNA and protein expression and activity, and reduce the expression and/or activity of matrix metallopeptidase (MMP) 9, MMP2 and C-myc. Also, CARM3 silencing increased E-cadherin expression and attenuated the expression of β-catenin. Moreover, we demonstrated that β-catenin overexpression reversed the inhibiting effect of CARMA3 silencing on cell invasion and migration. Furthermore, our study illustrated that knockdown of CARMA3 suppressed BC cells xenograft tumor growth in nude mice.

Conclusion

We demonstrated that CARMA3 contributes to the malignant phenotype of BC cells at least by activating β-catenin signaling pathway, and it may serve as a therapeutic target for clinic treatment in BC.

Small molecule inhibitors of epithelial-mesenchymal transition for the treatment of cancer and fibrosis

Tissue fibrosis and cancer both lead to high morbidity and mortality worldwide; thus, effective therapeutic strategies are urgently needed. Because drug resistance has been widely reported in fibrotic tissue and cancer, developing a strategy to discover novel targets for targeted drug intervention is necessary for the effective treatment of fibrosis and cancer. Although many factors lead to fibrosis and cancer, pathophysiological analysis has demonstrated that tissue fibrosis and cancer share a common process of epithelial-mesenchymal transition (EMT). EMT is associated with many mediators, including transcription factors (Snail, zinc-finger E-box-binding protein and signal transducer and activator of transcription 3), signaling pathways (transforming growth factor-β1, RAC-α serine/threonine-protein kinase, Wnt, nuclear factor-kappa B, peroxisome proliferator-activated receptor, Notch, and RAS), RNA-binding proteins (ESRP1 and ESRP2) and microRNAs. Therefore, drugs targeting EMT may be a promising therapy against both fibrosis and tumors. A large number of compounds that are synthesized or derived from natural products and their derivatives suppress the EMT by targeting these mediators in fibrosis and cancer. By targeting EMT, these compounds exhibited anticancer effects in multiple cancer types, and some of them also showed antifibrotic effects. Therefore, drugs targeting EMT not only have both antifibrotic and anticancer effects but also exert effective therapeutic effects on multiorgan fibrosis and cancer, which provides effective therapy against fibrosis and cancer. Taken together, the results highlighted in this review provide new concepts for discovering new antifibrotic and antitumor drugs.

Silibinin encapsulation in polymersome: A promising anticancer nanoparticle for inducing apoptosis and decreasing the expression level of miR-125b/miR-182 in human breast cancer cells

Silibinin, a polyphenolic flavonolignan, is well-known as a safe therapeutic drug without any side effects in the treatment of many malignancies especially cancerous cells. In this study, to overcome problems such as low solubility of silibinin and to enhance its delivery to cancerous cells, we encapsulated silibinin in polymersome nanoparticles. Physicochemical measurements such as dynamic light scattering, transmission electron microscopy, scanning electron microscopy, and atomic force microscopy confirmed the proper encapsulation of silibinin in nanoparticles. Furthermore, antiproliferative and apoptotic activities of silibinin encapsulated in polymersome nanoparticles (SPNs) on MDA-MB-231 breast cancer cell line were validated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide assay, Annexin V/Propidium Iodide measurement, and cell cycle analysis. In addition, quantitative reverse transcription polymerase chain reaction analysis confirmed that SPNs can repress oncogenic microRNAs (miRNAs) such as miR-125b and miR-182, as well as antiapoptotic genes such as Bcl2. SPNs can also induce overexpression of proapoptotic target genes such as P53, CASP9, and BAX directly and/or indirectly (through regulation of miRNAs). Our results suggested that polymersomes can be used as stable carriers in nano-dimensions and SPNs can be considered as a promising pharmacological agent for cancer therapy.

Long non-coding RNAs are emerging targets of phytochemicals for cancer and other chronic diseases

The long non-coding RNAs (lncRNAs) are the crucial regulators of human chronic diseases. Therefore, approaches such as antisense oligonucleotides, RNAi technology, and small molecule inhibitors have been used for the therapeutic targeting of lncRNAs. During the last decade, phytochemicals and nutraceuticals have been explored for their potential against lncRNAs. The common lncRNAs known to be modulated by phytochemicals include ROR, PVT1, HOTAIR, MALAT1, H19, MEG3, PCAT29, PANDAR, NEAT1, and GAS5. The phytochemicals such as curcumin, resveratrol, sulforaphane, berberine, EGCG, and gambogic acid have been examined against lncRNAs. In some cases, formulation of phytochemicals has also been used. The disease models where phytochemicals have been demonstrated to modulate lncRNAs expression include cancer, rheumatoid arthritis, osteoarthritis, and nonalcoholic fatty liver disease. The regulation of lncRNAs by phytochemicals can affect multi-steps of tumor development. When administered in combination with the conventional drugs, phytochemicals can also produce synergistic effects on lncRNAs leading to the sensitization of cancer cells. Phytochemicals target lncRNAs either directly or indirectly by affecting a wide variety of upstream molecules. However, the potential of phytochemicals against lncRNAs has been demonstrated mostly by preclinical studies in cancer models. How the modulation of lncRNAs by phytochemicals produce therapeutic effects on cancer and other chronic diseases is discussed in this review.

Epithelial-mesenchymal transition as a target for botanicals in cancer metastasis

BACKGROUND

The plant kingdom represents an unlimited source of phytotherapeutics with promising perspectives in the field of anticancer drug discovery.

PURPOSE

In this view, epithelial-mesenchymal transition (EMT) represents a novel and major target in anticancer therapy. Therefore, this narrative review aims to provide an updated overview on the bioactive phytochemicals with anti-EMT activity.

CONCLUSION

Among the plant products reviewed, phenylpropanoids were the most investigated at preclinical phase, thus exhibiting a promising potential as anticancer drugs, though an evidence-based clinical efficacy is still lacking.

β-catenin-coordinated lncRNA MALAT1 up-regulation of ZEB-1 could enhance the telomerase activity in HGF-mediated differentiation of bone marrow mesenchymal stem cells into hepatocytes

OBJECTIVE

To investigate role of β-catenin and lncRNA MALAT1/miR-217 axis to converge into the regulation of ZEB-1 in hepatocyte growth factor (HGF)-induced hepatocytes differentiated from bone marrow mesenchymal stem cells (BM-MSCs).

METHODS

BM-MSCs were isolated and HGF was used to induce the differentiation of BM-MSCs into hepatocytes. HSC-T6 cells, BRL-3 A cells and differentiated BM-MSCs were treated by lipopolysaccharide(LPS). shRNAs were used to silence β-catenin and recombinant plasmids were used to over-express ZEB1. Measurement of cell viability was conducted using MTT assay and Hoechst 33342 staining. RNA immunoprecipitation (RIP) assay was used to determine binding of miR-217-3p and MALAT1.

RESULTS

BM-MSCs successfully differentiated into hepatocytes by HGF treatment. Expression of β-catenin, ZEB-1 and TERT was up-regulated to a higher level in hepatocytes differentiated from BM-MSCs than HSC-T6 cells and BRL-3 A cells after LPS stimulation. When β-catenin was knocked down in all cell lines, expression of β-catenin, ZEB-1 and TERT was significantly decreased as well as telomerase activity. While when ZEB1 was over-expressed, expression of TERT and telomerase activity was all significantly up-regulated. In hepatocytes differentiated from BM-MSCs, miR-217 was down-regulated and lncRNA MALAT1 was up-regulated. RIP analysis showed MALAT1 was physically associated with miR-217 and might function in the regulation of ZEB-1, further enhancing the expression of TERT so as to augment telomerase activity.

CONCLUSION

We successfully used HGF to mediate differentiation of BM-MSCs into hepatocytes, and found that β-catenin-coordinated MALAT1/miR-217 axis could up-regulate expression of ZEB-1 and further enhanced the telomerase activity through regulation of TERT in BM-MSCs differentiating into hepatocytes.

Cabazitaxel and silibinin co-encapsulated cationic liposomes for CD44 targeted delivery: A new insight into nanomedicine based combinational chemotherapy for prostate cancer

Cancer stem cells (CSCs) are the promising targets for cancer chemotherapy that cannot be eliminated by conventional chemotherapy. In this study cationic liposomes of cabazitaxel (CBX) and silibinin (SIL) were prepared with an aim to kill cancer cells and CSCs for prostate cancer. CBX act as cancer cell inhibitor and SIL as CSC inhibitor. Hyaluronic acid (HA), an endogenous anionic polysaccharide was coated on cationic liposomes for targeting CD44 receptors over expressed on CSCs. Liposomes were prepared by ethanol injection method with particle size below 100 nm and entrapment efficiency of more than 90% at 10% w/w drug loading. Liposomes were characterized by dynamic light scattering, transmission electron microscopy, ¹H nuclear magnetic resonance and scanning electron microscopy-energy dispersive x-ray spectroscopy. Liposomes were evaluated for their anticancer action in androgen independent human prostate cancer cell lines (PC-3 and DU-145). HA coated liposomes showed potential cytotoxicity over other groups with low IC₅₀, significantly inhibited cell migration and induced apoptosis. Synergistic cytotoxic effect was also observed with HA coated liposomes that resulted in colony formation inhibition and G2/M phase arrest. Proficient cytotoxicity against CD44⁺ cells (14.87 ± 0.41% in PC-3 and 33.95 ± 0.68% in DU-145 cells) indicated the efficiency of HA coated liposomes towards CSC targeting. Hence, the outcome of this combinational therapy with CD44 targeting indicates the suitability of HA coated CBX and SIL co-loaded liposomes as a potential approach for eradicating prostate cancer and herein might provide a insight for future studies.

Tumor-associated macrophage-derived cytokines enhance cancer stem-like characteristics through epithelial-mesenchymal transition

Cancer stem cells are a small population of cells with the potential for self-renewal and multi-directional differentiation and are an important source of cancer initiation, treatment resistance, and recurrence. Epithelial-mesenchymal transition (EMT) is a process in which epithelial cells lose their epithelial phenotype and convert to mesenchymal cells. Recent studies have shown that cancer cells undergoing EMT can become stem-like cells. Many kinds of tumors are associated with chronic inflammation, which plays a role in tumor progression. Among the various immune cells mediating chronic inflammation, macrophages account for ~30%-50% of the tumor mass. Macrophages are highly infiltrative in the tumor microenvironment and secrete a series of inflammatory factors and cytokines, such as transforming growth factor (TGF)-β, IL-6, IL-10, and tumor necrosis factor (TNF)-α, which promote EMT and enhance the stemness of cancer cells. This review summarizes and discusses recent research findings on some specific mechanisms of tumor-associated macrophage-derived cytokines in EMT and cancer stemness transition, which are emerging targets of cancer treatment.