Zerumbone inhibits epithelial-mesenchymal transition and cancer stem cells properties by inhibiting the β-catenin pathway through miR-200c

Modulation of the tumor microenvironment by zerumbone and 5-fluorouracil in colorectal cancer by target in cancer-associated fibroblasts

BACKGROUND

This research aimed at the evaluation of the incremental effect(s) of combination therapy on colorectal cancer-associated fibroblasts (CAFs) in vivo and in vitro models of CRC. Drug resistance decreases the effectiveness of treatment for colorectal cancer (CRC) patients. CAFs, the main cells in the tumor stroma, contribute essentially to cancer drug resistance. Zerumbone (ZER) has been used for its anti-tumorigenic feature in various cancers. Also, 5-fluorouracil (5-FU) resistance is widely reported in advanced CRC patients. The possible impacts of combination therapy (or polytherapy is therapy that uses more than one medication or modality) with the use of herbs combined with chemical medicines may lead to improvement in patients' responses.

METHODS

According to the research design, the influence of 5-FU and ZER on the viability of the CT-26 cell line was examined through the MTT assay, and the size and dimension of the tumors were measured after 21 days of therapy in CRC BALB/c mice, and then the CAF cells were separated from the tissues of the tumors. Genes' mRNA expression and also the level of the proteins of the genes of interest (Survivin, Vimentin, & β -catenin) were evaluated using qRT-PCR and Western blotting on CT-26 and mouse-isolated CAF cells.

RESULTS AND CONCLUSIONS

We showed that ZER and 5-FU significantly increased our gene expression in the CT-26 cell line and isolated CAFs in the level of protein and mRNA in comparison to the controls (ZER-treated, untreated, & 5-FU-treated). Moreover, evaluating the size of the tumor in ZER and 5-FU-treated groups demonstrated a remarkable decline, which exhibited higher prominence in the group of combination therapy. A combination of natural and chemical drugs can largely enhance the effectiveness of cancer therapy.

Targeting epithelial-mesenchymal transition signaling pathways with Dietary Phytocompounds and repurposed drug combinations for overcoming drug resistance in various cancers

The epithelial-to-mesenchymal transition (EMT) is a crucial step in metastasis formation. It enhances the ability of cancer cells' to self-renew and initiate tumors, while also increasing resistance to apoptosis and chemotherapy. Among the signaling pathways a few signaling pathways such as Notch, TGF-beta, and Wnt-beta catenin are critically involved in the epithelial-to-mesenchymal transition (EMT) acquisition. Therefore, regulating EMT is a key strategy for controlling malignant cell behavior. This is done by interconnecting other signaling pathways in many cancer types. Although there is extensive preclinical evidence regarding EMT's function in the development of cancer, there is still a deficiency in clinical translation at the therapeutic level. Thus, there is a need for medications that are both highly effective and with low cytotoxic for modulating EMT transitions at ground level. Thus, this led to the study of the evaluation and efficiency of phytochemicals found in dietary sources of fruits and vegetables and also the combination of small molecular repurposed drugs that can enhance the effectiveness of traditional cancer treatments. This review summarises major EMT-associated pathways and their cross talks with their mechanistic insights and the role of different dietary phytochemicals (curcumin, ginger, fennel, black pepper, and clove) and their natural analogs and also repurposed drugs (metformin, statin, chloroquine, and vitamin D) which are commonly used in regulating EMT in various preclinical studies. This review also investigates the concept of low-toxicity and broad spectrum ("The Halifax Project") approach which can help for site targeting of several key pathways and their mechanism. We also discuss the mechanisms of action, models for our dietary phytochemicals, and repurposed drugs and their combinations used to identify potential anti-EMT activities. Additionally, we also analyzed existing literature and proposed new directions for accelerating the discovery of novel drug candidates that are safe to administer.

Anti-cancer potential of zerumbone in cancer and glioma: current trends and future perspectives

Plant-derived immunomodulators and antitumor factors have appealed lots of attention from natural product scientists for their efficiency and safety and their important contribution to well-designed targeted drug action and delivery mechanisms. Zerumbone (ZER), the chief component of Zingiber zerumbet rhizomes, has been examined for its wide-spectrum in the treatment of multi-targeted diseases. The rhizomes have been used as food flavoring agents in numerous cuisines and in flora medication. Numerous in vivo and in vitro experiments have prepared confirmation of ZER as a potent immunomodulator as well as a potential anti-tumor agent. This review is an interesting compilation of all the important results of the research carried out to date to investigate the immunomodulatory and anticancer properties of ZER. The ultimate goal of this comprehensive review is to supply updated information and a crucial evaluation on ZER, including its chemistry and immunomodulating and antitumour properties, which may be of principal importance to supply a novel pathway for subsequent investigation to discover new agents to treat cancers and immune-related sickness. In addition, updated information on the toxicology of ZER has been summarized to support its safety profile.

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.

Emerging agents that target signaling pathways to eradicate colorectal cancer stem cells

Colorectal cancer (CRC) represents the third most commonly diagnosed cancer and the second leading cause of cancer death worldwide. The modern concept of cancer biology indicates that cancer is formed of a small population of cells called cancer stem cells (CSCs), which present both pluripotency and self-renewal properties. These cells are considered responsible for the progression of the disease, recurrence and tumor resistance. Interestingly, some cell signaling pathways participate in CRC survival, proliferation, and self-renewal properties, and most of them are dysregulated in CSCs, including the Wingless (Wnt)/β-catenin, Notch, Hedgehog, nuclear factor kappa B (NF-κB), Janus kinase/signal transducer and activator of transcription (JAK/STAT), peroxisome proliferator-activated receptor (PPAR), phosphatidyl-inositol-3-kinase/Akt/mechanistic target of rapamycin (PI3K/Akt/mTOR), and transforming growth factor-β (TGF-β)/Smad pathways. In this review, we summarize the strategies for eradicating CRC stem cells by modulating these dysregulated pathways, which will contribute to the study of potential therapeutic schemes, combining conventional drugs with CSC-targeting drugs, and allowing better cure rates in anti-CRC therapy.

Bioactive Compounds from Zingiber montanum and Their Pharmacological Activities with Focus on Zerumbone

The genus Zingiber consists of about 85 species and many of these species are used as food, spices, and medicines. One of the species, Zingiber montanum (J. Koenig) Link ex A. Dietr. is native to Southeast Asia and has been extensively used as traditional medicines and food. The aim of this review was to collect and critically analyze the scientific information about the bioactive compounds and pharmacological activities of Z. montanum with focus on one of the main components, zerumbone (ZER). Various studies have reported the analysis of volatile constituents of the essential oils from Z. montanum. Similarly, many phenylbutanoids, flavonoids and terpenes were also isolated from rhizomes. These essential oils, extracts and compounds showed potent antimicrobial, anti-inflammatory and antioxidant activities among others. Zerumbone has been studied widely for its anticancer, anti-inflammatory, and other pharmacological activities. Future studies should focus on the exploration of various pharmacological activities of other compounds including phenylbutanoids and flavonoids. Bioassay guided isolation may result in the separation of other active components from the extracts. Z. montanum could be a promising source for the development of pharmaceutical products and functional foods.

Zerumbone, a ginger sesquiterpene, inhibits migration, invasion, and metastatic behavior of human malignant glioblastoma multiforme in vitro

The most widespread and challenging aggressive malignant tumor in the brain is glioblastoma multiforme (GBM). GBM is characterized, in particular, by significant intratumor cell variability, high growth rates, and widespread invasiveness within the surrounding normal brain parenchyma. The present study aimed to examine the impact of the natural product Zerumbone, a promising sesquiterpenoid phytochemical from Zingiber zerumbet, on U-87 MG GBM cells and its underlying molecular mechanisms. At sub-lethal doses, Zerumbone exerted a concentration- and time-dependent suppression of cell migration ability utilizing scratch wound closure assay; it also inhibited GBM cells' invasion using Transwell invasion assay in a concentration-dependent fashion. The enzymatic activity of matrix metalloproteinase (MMP)-2/-9 and their protein expression has also been reduced by administration of Zerumbone. Furthermore, Zerumbone was revealed to downregulate the mRNA expression level of IL-1β and MCP-1, two genes contributing to MMPs expression. We also found that Zerumbone exerted an inhibitory effect on the expression of Akt and total p44/42 MAPK (Erk1/Erk2) against U-87 MG cells. These findings collectively provide further proof for the possible molecular signaling basis of the antimetastatic effects of Zerumbone as a promising phytochemical, indicating a therapeutic strategy for the treatment of GBM through repression of migration, invasion, and metastasis.

Recent Updates on Mechanisms of Resistance to 5-Fluorouracil and Reversal Strategies in Colon Cancer Treatment

5-Fluorouracil (5-FU) plus leucovorin (LV) remain as the mainstay standard adjuvant chemotherapy treatment for early stage colon cancer, and the preferred first-line option for metastatic colon cancer patients in combination with oxaliplatin in FOLFOX, or irinotecan in FOLFIRI regimens. Despite treatment success to a certain extent, the incidence of chemotherapy failure attributed to chemotherapy resistance is still reported in many patients. This resistance, which can be defined by tumor tolerance against chemotherapy, either intrinsic or acquired, is primarily driven by the dysregulation of various components in distinct pathways. In recent years, it has been established that the incidence of 5-FU resistance, akin to multidrug resistance, can be attributed to the alterations in drug transport, evasion of apoptosis, changes in the cell cycle and DNA-damage repair machinery, regulation of autophagy, epithelial-to-mesenchymal transition, cancer stem cell involvement, tumor microenvironment interactions, miRNA dysregulations, epigenetic alterations, as well as redox imbalances. Certain resistance mechanisms that are 5-FU-specific have also been ascertained to include the upregulation of thymidylate synthase, dihydropyrimidine dehydrogenase, methylenetetrahydrofolate reductase, and the downregulation of thymidine phosphorylase. Indeed, the successful modulation of these mechanisms have been the game plan of numerous studies that had employed small molecule inhibitors, plant-based small molecules, and non-coding RNA regulators to effectively reverse 5-FU resistance in colon cancer cells. It is hoped that these studies would provide fundamental knowledge to further our understanding prior developing novel drugs in the near future that would synergistically work with 5-FU to potentiate its antitumor effects and improve the patient's overall survival.

Mechanisms of Chemopreventive and Therapeutic Proprieties of Ginger Extracts in Cancer

Ginger (Zingiber officinale Roscoe, family: Zingiberaceae), originating in South-East Asia, is one of the most used spices and condiments for foods and beverages. It is also used in traditional medicine for many human disorders including fever, gastrointestinal complications, arthritis, rheumatism, hypertension, and various infectious diseases due to its anti-inflammatory, antioxidant, antimicrobial, and antiemetic properties. Intriguingly, many recent studies evidenced the potent chemopreventive characteristics of ginger extracts against different types of cancer. The aim of this work is to review the literature related to the use of ginger extracts as a chemotherapeutic agent and to structure the cellular and molecular mechanisms through which ginger acts in different cancer types. Data summarized from experiments (in vitro or in vivo) and clinical studies, evidenced in this review, show that ginger derivatives perpetrate its anti-tumor action through important mediators, involved in crucial cell processes, such as cell cycle arrest, induction of cancer cell death, misbalance of redox homeostasis, inhibition of cell proliferation, angiogenesis, migration, and dissemination of cancer cells.

Sec62 promotes stemness and chemoresistance of human colorectal cancer through activating Wnt/β-catenin pathway

BACKGROUND

Cancer stem cell (CSC)-related chemoresistance leads to poor outcome of the patients with colorectal cancer (CRC). In this study, we identified the chemoresistance-relevant molecules and decipher the involved mechanisms to provide potential therapeutic target for CRC. We focused on Sec62, a novel target with significantly increased expression in chemoresistant CRC tissues, and further investigated its role in the progression of CRC.

METHODS

Through analyzing the differentially-expressed genes between chemoresistant and chemosensitive CRCs, we selected Sec62 as a novel chemoresistance-related target in CRC. The expression and clinical significance of Sec62 were determined by immunoblotting and immunohistochemistry in tissues and cell lines of CRC. The roles of Sec62 in drug resistance, stemness and tumorigenesis were evaluated in vitro and in vivo using functional experiments. GST pull-down, western blot, coimmunoprecipitation and Me-RIP assays were performed to further explore the downstream molecular mechanisms.

RESULTS

Sec62 upregulation was associated with the chemoresistance of CRC and poor outcome of CRC patients. Depletion of Sec62 sensitized CRC cells to chemotherapeutic drugs. Sec62 promoted the stemness of CRC cells through activating Wnt/β-catenin signaling. Mechanistically, Sec62 bound to β-catenin and inhibited the degradation of β-catenin. Sec62 competitively disrupted the interaction between β-catenin and APC to inhibit the β-catenin destruction complex assembly. Moreover, Sec62 expression was upregulated by the m6A-mediated stabilization of Sec62 mRNA.

CONCLUSIONS

Sec62 upregulated by the METTL3-mediated m6A modification promotes the stemness and chemoresistance of CRC by binding to β-catenin and enhancing Wnt signalling. Thus, m6A modification-Sec62-β-catenin molecular axis might act as therapeutic targets in improving treatment of CRC.

The Combination of Zerumbone and 5-FU: A Significant Therapeutic Strategy in Sensitizing Colorectal Cancer Cells to Treatment

Objectives. Chemotherapy is considered to be essential in the treatment of patients with colorectal cancer (CRC), but drug resistance reduces its efficacy. Many patients with advanced CRC eventually show resistance to 5-fluorouracil (5-FU) therapy. Synergistic and potentiating effects of combination therapy, using herbal and chemical drugs, can improve patients’ response. Zerumbone (ZER), which is derived from ginger, has been studied for its growth inhibitory function in various types of cancer. Methods. The cytotoxic effects of ZER and 5-FU alone and their combination, on the SW48 and HCT-116 cells, were examined, using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT). The mRNA and protein levels of β-catenin, survivin, and vimentin were measured in treated CRC cells, using qRT-PCR and western blot. Colony formation assay, scratch test, and flow cytometry were performed to detect the changes of proliferation, migration, and apoptosis. Key Findings. In HCT-116- and SW48-treated cells, the proliferation, the gene and protein expression levels of the markers, the migration, the colony formation, and the survival rates were all significantly reduced compared to the control groups, and the sharpest decline was observed in the 5-FU+ZER treatment groups. Conclusions. Combination therapy has shown promising results in CRC cells, especially in drug-resistant cells.

Relationship between Sphk1/S1P and microRNAs in human cancers

Sphingosine kinases type 1 (SphK1) is a key enzyme in the phosphorylation of sphingosine to sphingosine 1-phosphate (S1P). Different abnormalities in SphK1 functions may correspond with poor prognosis in various cancers. Additionally, upregulated SphK1/S1P could promote cancer cell proliferation, angiogenesis, mobility, invasion, and metastasis. MicroRNAs as conserved small noncoding RNAs play major roles in cancer initiation, progression, metastasis, etc. Their posttranscriptionally mechanisms could affect the development of cancer growth or tumorigenesis suppression. The growing number of studies has described that various microRNAs can be regulated by SphK1, and its expression level can also be regulated by microRNAs. In this review, the relationship of SphK1 and microRNA functions and their interaction in human malignancies have been discussed. Based on them novel treatment strategies can be introduced.

Curry versus cancer: Potential of some selected culinary spices against cancer with in vitro, in vivo, and human trials evidences

Spices are dietary agents with immense potential for cancer chemo-prevention. A wide variety of spices are extensively used as food flavoring agents which possess potent antioxidant, anti-inflammatory, and anticancer properties due to the presence of certain bio-active compounds in them. In vitro, in vivo studies and clinical trials of selected spices against various types of cancer are being specified in this review. Effect of certain putative dietary spices namely turmeric, clove, garlic, ginger, fennel, black cumin, cinnamon, pepper, saffron, rosemary, and chilli along with its role in cancer are being discussed. Literature search was conducted through PubMed, Google scholar, Science direct, and Scopus using the keywords "spice," "cancer," "natural medicine," "herbal compound," "bioactive compounds." About 4,000 published articles and 127 research papers were considered to grab the brief knowledge on spices and their anticancer potential on a predefined inclusion and exclusion criteria. PRACTICAL APPLICATION: Historically, spices and herbs are known for its traditional flavor, odor, and medicinal properties. Intensified risk of chronic and pervasive clinical conditions and increased cost of advanced drug treatments have developed a keen interest among researchers to explore the miscellaneous properties of herbal spices. Cancer is one of the deleterious causes of mortality affecting a huge number of populations worldwide. Arrays of cancer treatments including surgery, chemotherapy, and radiation therapy are used to compromise the disease but effective only when the size of the tumor is small. So, an effective treatment need to be developed that produces less side effects and herbal spices are found to be the promising agents. In this review, we illustrate about different in vitro, in vivo, and clinical studies of wide range of culinary spices having antineoplastic potential.

Portrait of Cancer Stem Cells on Colorectal Cancer: Molecular Biomarkers, Signaling Pathways and miRNAome

Colorectal cancer (CRC) is a leading cause of cancer death worldwide, and about 20% is metastatic at diagnosis and untreatable. Increasing evidence suggests that the heterogeneous nature of CRC is related to colorectal cancer stem cells (CCSCs), a small cells population with stemness behaviors and responsible for tumor progression, recurrence, and therapy resistance. Growing knowledge of stem cells (SCs) biology has rapidly improved uncovering the molecular mechanisms and possible crosstalk/feedback loops between signaling pathways that directly influence intestinal homeostasis and tumorigenesis. The generation of CCSCs is probably connected to genetic changes in members of signaling pathways, which control self-renewal and pluripotency in SCs and then establish function and phenotype of CCSCs. Particularly, various deregulated CCSC-related miRNAs have been reported to modulate stemness features, controlling CCSCs functions such as regulation of cell cycle genes expression, epithelial-mesenchymal transition, metastasization, and drug-resistance mechanisms. Primarily, CCSC-related miRNAs work by regulating mainly signal pathways known to be involved in CCSCs biology. This review intends to summarize the epigenetic findings linked to miRNAome in the maintenance and regulation of CCSCs, including their relationships with different signaling pathways, which should help to identify specific diagnostic, prognostic, and predictive biomarkers for CRC, but also develop innovative CCSCs-targeted therapies.

Promising Effects of Zerumbone on the Regulation of Tumor-promoting Cytokines Induced by TNF-α-activated Fibroblasts

Inflammation plays an important role in the development of several cancers. Inflammatory cytokines, including tumor necrosis factor-α (TNF-α), are associated with the induction of inflammation. Chronic inflammation contributes to the progression of cancer through several mechanisms, including increased cytokine production and activation of transcription factors, such as nuclear factor-κB (NF-κB). Zerumbone (ZER), a component of subtropical ginger (Zingiber zerumbet Smith), seems to have anti-inflammatory, anti-cancer, and antioxidant activities. In this study, we aimed to explore the protective function and mechanisms of ZER against TNF-α-induced cancer-promoting cytokines. We found that the viability of stimulated human fibroblast cell lines was reduced after treatment with ZER (IC₅₀=18 µmol/L), compared to un-stimulated fibroblasts (IC₅₀=40 µmol/L). Besides, ZER inhibited mRNA expression and protein secretion of transforming growth factor-β (TGF-β), interleukin-33 (IL-33), monocyte chemoattractant protein-1 (MCP-1), and stromal cell-derived factor 1 (SDF-1), which were produced by TNF-α-induced fibroblasts, as measured by quantitative real time-PCR (qRT-PCR) and ELISA assays. The mRNA expression levels of TGF-β, IL-33, SDF-1, and MCP-1 showed 8, 5, 2.5, and 4-fold reductions, respectively. Moreover, secretion of TGF-β, IL-33, SDF-1, and MCP-1 was reduced to 3.65±0.34 ng/mL, 6.3±0.26, 1703.6±295.2, and 5.02±0.18 pg/mL, respectively, compared to the untreated group. In addition, the conditioned media (CM) of TNF-α-stimulated fibroblasts increased the NF-κB expression in colorectal cancer cell lines (HCT-116 and Sw48), while in the vicinity of ZER, the expression of NF-κB was reversed. Considering the significant effects of ZER, this component can be used as an appropriate alternative herbal treatment for cancer-related chronic inflammation.

MiR-200c/FUT4 axis prevents the proliferation of colon cancer cells by downregulating the Wnt/β-catenin pathway

BACKGROUND

MicroRNA (miR)-200c has been widely reported to be involved in colon cancer progress. However, the mechanisms of miR-200c in regulating tumor metastasis and growth remain to be fully elucidated. This study aimed to investigate the mechanism of miR-200c targets fucosyltransferase 4 (FUT4) on the proliferation of colon cancer.

METHODS

The miR-200c and FUT4 mRNA levels in LoVo and SW480 cells were measured by real-time quantitative polymerase chain reaction. Further, miR-200c mimic, FUT4 siRNA and FUT4 mimic were transfected into cells, separately. Cell counting kit-8, plate colony formation and transwell assays were used to analyse the cells biological behaviour.. Immunofluorescence was used to analyse the Ki-67 expression Moreover, the Wnt/β-catenin pathway-related proteins were detected by western blots. A double luciferase experiment was performed to confirm the relationship between miR-200c and FUT4. In vivo, tumour growth and Wnt/β-catenin pathway-related proteins were also analysed.

RESULTS

In vitro, the expression of miR-200c and FUT4 were negatively correlated in LoVo and SW480 cells (correlation coefficients were - 0.9046 and - 0.9236, respectively). MiR-200c overexpression inhibited the proliferation, migration and invasion of LoVo and SW480 cells by downregulating FUT4. The Ki67-positive cells and Wnt/β-catenin signalling pathway-related proteins were reduced in the miR-200c overexpression and FUT4 silencing groups. A dual luciferase reporting system identified FUT4 as the target of miR-200c. The results in vivo were further confirmed the foundation of cells study.

CONCLUSIONS

In summary, miR-200c overexpression inhibits proliferation of colon cancer targeting FUT4 to downregulate the Wnt/β-catenin pathway, which promises molecular targets to inhibit metastasis for colon cancer therapy.

Sesquiterpenes and their derivatives-natural anticancer compounds: An update

Sesquiterpenes belong to the largest group of plant secondary metabolites, which consist of three isoprene building units. These compounds are widely distributed in various angiosperms, a few gymnosperms and bryophytes. Sesquiterpenes and their allied derivatives are bio-synthesized in various plant parts including leaves, fruits and roots. These plant-based metabolites are predominantly identified in the Asteraceae family, wherein up to 5000 complexes have been documented to date. Sesquiterpenes and their derivatives are characteristically associated with plant defence mechanisms owing to their antifungal, antibacterial and antiviral activities. Over the last two decades, these compounds have been reportedly demonstrated health promoting perspectives against a wide range of metabolic syndromes i.e. hyperglycemia, hyperlipidemia, cardiovascular complications, neural disorders, diabetes, and cancer. The high potential of sesquiterpenes and their derivatives against various cancers like breast, colon, bladder, pancreatic, prostate, cervical, brain, liver, blood, ovarium, bone, endometrial, oral, lung, eye, stomach and kidney are the object of this review. Predominantly, it recapitulates the literature elucidating sesquiterpenes and their derivatives while highlighting the mechanistic approaches associated with their potent anticancer activities such as modulating nuclear factor kappa (NF-kB) activity, inhibitory action against lipid peroxidation and retarding the production of reactive oxygen & nitrogen species (ROS&RNS).

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.

Role of Wnt/β-Catenin Signaling in the Chemoresistance Modulation of Colorectal Cancer

Colorectal cancer (CRC) is a common malignancy with high morbidity and mortality worldwide. To date, chemotherapy plays an important role in the treatment of CRC patients. Multidrug resistance (MDR) is one of the major hurdles in chemotherapy for CRC, and the underlying mechanisms need to be explored. Studies have demonstrated that Wnt/β-catenin signaling plays a critical role in oncogenesis and tumor development, and its function in inhibiting apoptosis could facilitate tumor chemoresistance. Recent investigations have also suggested the regulatory effects of the Wnt/β-catenin signaling pathway in response to chemotherapeutic agents in CRC. Here, we particularly focus on reviewing the evidences suggesting the mechanisms of Wnt/β-catenin signaling in the chemoresistance modulation of colorectal cancer.

6 α-Hydroxy-4[14], 10[15]-guainadien-8β, 12-olide induced cell cycle arrest via modulation of EMT and Wnt/β-catenin pathway in HER-2 positive breast cancer cells

Cyathocline purpurea has potential biological activities and has been widely used in traditional Chinese and Ayurvedic medicine. The aim of the present study is to elucidate the anticancer effect of its 6 α-hydroxy-4[14], 10[15]-guainadien-8β, 12-olide (SRCP1) against HER-2 positive subtype of breast carcinoma. Anticancer effect of SRCP1 was assessed by cell viability, senescence, apoptosis, cell cycle, DNA synthesis, and gene expression assays. The activity was further validated by the molecular docking study. SRCP1 inhibits human HER-2 positive breast cancer growth via inhibition of DNA synthesis in a dose-dependent manner. SRCP1 induces cell cycle arrest at G₂/M phase, late apoptosis, and necrosis. Further, it induces senescence causing reduction in migration via down-regulation of EMT. A remarkable increase in the number of necrotic cells and Annexin-V staining revealed that exposure to SRCP1 triggers late apoptosis. Treatment with SRCP1 increased E-cadherin, p21, p53, ER-α expression and decreased β-catenin, MMP-9, snail1, TNF-α expression. SRCP1 showed binding affinity towards an active site of the HER-2 receptor. Our results of molecular docking and biological assays demonstrated the potent anticancer activity of SRCP1 in MDA-MB-453 cells via multiple pathways including EMT, TNF-α, and Wnt/β-catenin signaling.

Protective Effects of Zerumbone on Colonic Tumorigenesis in Enterotoxigenic Bacteroides fragilis (ETBF)-Colonized AOM/DSS BALB/c Mice

Chronic inflammation has been linked to colitis-associated colorectal cancer in humans. The human symbiont enterotoxigenic Bacteroides fragilis (ETBF), a pro-carcinogenic bacterium, has the potential to initiate and/or promote colorectal cancer. Antibiotic treatment of ETBF has shown promise in decreasing colonic polyp formation in murine models of colon cancer. However, there are no reported natural products that have shown efficacy in decreasing polyp burden. In this study, we investigated the chemopreventive effects of oral administration of zerumbone in ETBF-colonized mice with azoxymethane (AOM)/dextran sulfate sodium (DSS)-induced tumorigenesis. Zerumbone significantly reduced the severity of disease activity index (DAI) scores as well as several parameters of colonic inflammation (i.e., colon weight, colon length, cecum weight and spleen weight). In addition, inflammation of the colon and cecum as well as hyperplasia was reduced. Zerumbone treatment significantly inhibited colonic polyp numbers and prevented macroadenoma progression. Taken together, these findings suggest that oral treatment with zerumbone inhibited ETBF-promoted colon carcinogenesis in mice indicating that zerumbone could be employed as a promising protective agent against ETBF-mediated colorectal cancer.

Roles of microRNAs as non-invasive biomarker and therapeutic target in colorectal cancer

MicroRNAs are endogenous, short non-coding RNA molecules that function as critical regulators of various biological processes. There is a strong functional evidence linking the involvement of dysregulated miRNAs to the occurrence, development and progression of colorectal cancer. Studies indicate that while overexpression of oncomiRs, and repression of tumor suppressor miRNAs tends to drive the overall tumorigenic process, the global picture of aberrant miRNA expression in colorectal cancer can classify the disease into multiple molecular phenotypes. Moreover, the expression pattern of miRNAs in colorectal cancer make them viable disease determinants as well as potential therapeutic targets. Through this review, we will summarize the importance of miRNAs in the etiology and progression of colorectal cancer. Specifically, we will explore the key role played by these RNA molecules as likely therapeutic avenues and the strategies presently available to target them. Finally, we will investigate the role of miRNAs as potential non-invasive diagnostic and prognostic biomarkers in colorectal cancer.

Enhancement of MicroRNA-200c on Osteogenic Differentiation and Bone Regeneration by Targeting Sox2-Mediated Wnt Signaling and Klf4

MicroRNA (miR)-200c functions in antitumorigenesis and mediates inflammation and osteogenic differentiation. In this study, we discovered that miR-200c was upregulated in human bone marrow mesenchymal stromal cells (hBMSCs) during osteogenic differentiation. Inhibition of endogenous miR-200c resulted in downregulated osteogenic differentiation of hBMSCs and reduced bone volume in the maxilla and mandible of a transgenic mouse model. Overexpression of miR-200c by transfection of naked plasmid DNA (pDNA) encoding miR-200c significantly promoted the biomarkers of osteogenic differentiation in hBMSCs, including alkaline phosphatase, Runt-related transcription factor 2, osteocalcin, and mineral deposition. The pDNA encoding miR-200c also significantly enhanced bone formation and regeneration in calvarial defects of rat models. In addition, miR-200c overexpression was shown to downregulate SRY (sex determining region Y)-box 2 (Sox2) and Kruppel-like factor 4 by directly targeting 3'-untranslated regions and upregulate the activity of Wnt signaling inhibited by Sox2. These results strongly indicated that miR-200c may serve as a unique osteoinductive agent applied for bone healing and regeneration.

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.

Potential of Zerumbone as an Anti-Cancer Agent

Cancer is still a major risk factor to public health globally, causing approximately 9.8 million deaths worldwide in 2018. Despite advances in conventional treatment modalities for cancer treatment, there are still few effective therapies available due to the lack of selectivity, adverse side effects, non-specific toxicities, and tumour recurrence. Therefore, there is an immediate need for essential alternative therapeutics, which can prove to be beneficial and safe against cancer. Various phytochemicals from natural sources have been found to exhibit beneficial medicinal properties against various human diseases. Zerumbone is one such compound isolated from Zingiber zerumbet Smith that possesses diverse pharmacological properties including those of antioxidant, antibacterial, antipyretic, anti-inflammatory, immunomodulatory, as well as anti-neoplastic. Zerumbone has shown its anti-cancer effects by causing significant suppression of proliferation, survival, angiogenesis, invasion, and metastasis through the molecular modulation of different pathways such as NF-κB, Akt, and IL-6/JAK2/STAT3 (interleukin-6/janus kinase-2/signal transducer and activator of transcription 3) and their downstream target proteins. The current review briefly summarizes the modes of action and therapeutic potential of zerumbone against various cancers.

Emerging ways to treat breast cancer: will promises be met?

BACKGROUND

Breast cancer (BC) is the most common cancer among women and it is responsible for more than 40,000 deaths in the United States and more than 500,000 deaths worldwide each year. In previous decades, the development of improved screening, diagnosis and treatment methods has led to decreases in BC mortality rates. More recently, novel targeted therapeutic options, such as the use of monoclonal antibodies and small molecule inhibitors that target specific cancer cell-related components, have been developed. These components include ErbB family members (HER1, HER2, HER3 and HER4), Ras/MAPK pathway components (Ras, Raf, MEK and ERK), VEGF family members (VEGFA, VEGFB, VEGFC, VEGF and PGF), apoptosis and cell cycle regulators (BAK, BAX, BCL-2, BCL-X, MCL-1 and BCL-W, p53 and PI3K/Akt/mTOR pathway components) and DNA repair pathway components such as BRCA1. In addition, long noncoding RNA inhibitor-, microRNA inhibitor/mimic- and immunotherapy-based approaches are being developed for the treatment of BC. Finally, a novel powerful technique called CRISPR-Cas9-based gene editing is emerging as a precise tool for the targeted treatment of cancer, including BC.

CONCLUSIONS

Potential new strategies that are designed to specifically target BC are presented. Several clinical trials using these strategies are already in progress and have shown promising results, but inherent limitations such as off-target effects and low delivery efficiencies still have to be resolved. By improving the clinical efficacy of current therapies and exploring new ones, it is anticipated that novel ways to overcome BC may become attainable.