Migration Of HeLa Cells Research Articles

RNA interference of HERC4 inhibits proliferation, apoptosis and migration of cervical cancer Hela cells

To explore the effects of silencing HERC4 on the proliferation, apoptosis, and migration of cervical cancer cell line Hela and the possible molecular mechanisms. Three HERC4-specific small interfering RNAs (siRNAs) were transfected into Hela cells, and HERC4 expression in the cells was examined with Western blotting. CCK-8 assay, annexin V-FITC/PI assay, and wound healing assay were used to assess the effect of HERC4 silencing on the proliferation, apoptosis and migration ability of Hela cells. The expression levels of cyclin D1 and Bcl-2 in the cells were detected using Western blotting. Transfection of siRNA-3 resulted in significantly decreased HERC4 protein expression (P<0.01). HERC4 silencing by siRNA-3 markedly suppressed the proliferation and migration of Hela cells, increased the apoptosis rate (P<0.01) and reduced the expression levels of cyclin D1 and Bcl-2 (P<0.01). Silencing of HERC4 efficiently inhibits the proliferation, migration, and invasion of Hela cells in vitro, and the underlying mechanisms may involve the down-regulation of cyclin D1 and Bcl-2.

MicroRNA-183 functions as the tumor suppressor via inhibiting cellular invasion and metastasis by targeting MMP-9 in cervical cancer

ObjectiveMicroRNAs have been reported to play an important role in the invasion and metastasis of cervical cancer. miR-183 was found to inhibit or promote the invasion and metastasis of multiple solid tumors. However, the roles of miR-183 in cervical cancer are unclear. MethodsIn this study, miR-183 expression levels were measured in 53 cervical cancer and 13 normal cervical tissues by qRT-PCR. The effects of forced expression of miR-183 on cervical cancer cells invasion and metastasis were investigated using Transwell uncoated or coated with growth factor-reduced Matrigel for migration or invasion assays, respectively. ResultsWe found that miR-183 expression levels were significantly down-regulated in cervical cancer tissues compared with normal tissues (0.15±0.011 to 0.86±0.049). Ectopic expression of miR-183 resulted in the suppression of invasion and migration of cervical cancer cell lines, siha and Hela cells (p<0.0001). Bioinformatics analysis revealed that MMP-9 was the potential target of miR-183 and it was found that MMP-9 was remarkably up-regulated in cervical cancer. Furthermore, a dual-luciferase reporter assay showed that MMP-9 as a target of miR-183 (p<0.0001). The invasion and metastasis ability of siha and Hela was suppressed when MMP-9 was down-regulated in vitro (p<0.0001). ConclusionsIn conclusion, our study revealed that miR-183 might be a tumor suppressor via inhibiting the invasion and metastasis of cervical cancer cells through targeting MMP-9, indicating that miR-183 may be a novel potential therapeutic target for cervical cancer.

Non-thermal plasma inhibits human cervical cancer HeLa cells invasiveness by suppressing the MAPK pathway and decreasing matrix metalloproteinase-9 expression.

Non-thermal plasma (NTP) has been proposed as a novel therapeutic method for anticancer treatment. However, the mechanism underlying its biological effects remains unclear. In this study, we investigated the inhibitory effect of NTP on the invasion of HeLa cells, and explored the possible mechanism. Our results showed that NTP exposure for 20 or 40 s significantly suppressed the migration and invasion of HeLa cells on the basis of matrigel invasion assay and wound healing assay, respectively. Moreover, NTP reduced the activity and protein expression of the matrix metalloproteinase (MMP)-9 enzyme. Western blot analysis indicated that NTP exposure effectively decreased phosphorylation level of both ERK1/2 and JNK, but not p38 MAPK. Furthermore, treatment with MAPK signal pathway inhibitors or NTP all exhibited significant depression of HeLa cells migration and MMP-9 expression. The result showed that NTP synergistically suppressed migration and MMP-9 expression in the presence of ERK1/2 inhibitor and JNK inhibitor, but not p38 MAPK inhibitor. Taken together, these findings suggested that NTP exposure inhibited the migration and invasion of HeLa cells via down-regulating MMP-9 expression in ERK1/2 and JNK signaling pathways dependent manner. These findings provide hints to the potential clinical research and therapy of NTP on cervical cancer metastasis.

MicroRNA-106b is involved in transforming growth factor β1-induced cell migration by targeting disabled homolog 2 in cervical carcinoma.

BackgroundMicroRNA-106b (miR-106b) was recently identified as an oncogene participating in cancer progression. Transforming growth factor β1(TGF-β1) is an indispensable cytokine regulating the local microenvironment, thereby promoting cervical cancer progression. However, the roles of miR-106b in cervical carcinoma progression and TGF-β1-involvement in the tumorigenesis of cervical cancer remain unknown.MethodsThe expression of miR-106b in human cervical specimens was detected by real-time PCR analysis and in situ hybridization assay. The effect of miR-106b on cell migration was analyzed by scratch and transwell assays. TGF-β1 was used to induce cell migration. The expression of the miR-106b target gene DAB2 in human cervical tissues and cell lines were measured by qRT-PCR, western blot and immunohistochemistry. Dual-luciferase reporter assay was used to identify DAB2 as a miR-106b-directed target gene.ResultsmiR-106b was frequently up-regulated in human cervical carcinoma specimens and cervical cancer cell lines. Over-expression of miR-106b significantly promoted HeLa and SiHa cells migration. Likewise, inhibition of miR-106b decreased HeLa and SiHa cells migration. The multifunctional cytokine TGF-β facilitates metastasis in cervical carcinoma. miR-106b inhibitor treatment decreased the TGF-β1-stimulated migration of HeLa and SiHa cells. DAB2, a predicted target gene of miR-106b, was inhibited by TGF-β1 partly through miR-106b and was involved in TGF-β1-induced cervical cancer cell migration. The expression of DAB2 was low in cervical cancer tissues, and negatively correlated with miR-106b expression. Finally, DAB2 was identified as a miR-106b-directed target gene by dual-luciferase reporter assay.ConclusionOur data suggest that the TGF-β1/miR-106b/DAB2 axis may be involved in the pathogenesis of cervical carcinoma.

Adenosine inhibits migration, invasion and induces apoptosis of human cervical cancer cells.

Extracellular adenosine is akey signaling molecule which mediates immune suppression, angiogenesis, and regulates cancer cells growth. The effect of adenosine on cervical cancer cells migration and invasion has not been well studied. In the current study, we used Hela and SiHa cell lines to evaluate the effects of adenosine on cervical cancer cells migration, invasion, and apoptosis. The results showed that adenosine treatment inhibited the migration and invasion activities of Hela and SiHa cells. Moreover, by determining the expression of molecules which were involved in epithelial to mesenchymal transition (EMT) progress, we found that epithelial marker E-cadherin was significantly increased in response to adenosine treatment, while the mesenchymal markers including N-cadherin and fibronectin were decreased. These data suggested that adenosine inhibited cervical cancer cells via repressing the EMT progress. The flow cytometry analysis showed that adenosine could also induce cervical cancer cell apoptosis, which mechanism was further confirmed by investigating the expression levels of apoptosis related molecules, via activating mitochondrial apoptosis pathway. These data might suggest that adenosine could be used as an agent for the treatment of cervical cancer.

Thymidine 5'-O-monophosphorothioate induces HeLa cell migration by activation of the P2Y6 receptor.

ATP, ADP, UTP, and UDP acting as ligands of specific P2Y receptors activate intracellular signaling cascades to regulate a variety of cellular processes, including proliferation, migration, differentiation, and cell death. Contrary to a widely held opinion, we show here that nucleoside 5'-O-monophosphorothioate analogs, containing a sulfur atom in a place of one nonbridging oxygen atom in a phosphate group, act as ligands for selected P2Y subtypes. We pay particular attention to the unique activity of thymidine 5'-O-monophosphorothioate (TMPS) which acts as a specific partial agonist of the P2Y6 receptor(P2Y6R). We also collected evidence for the involvement of the P2Y6 receptor in human epithelial adenocarcinoma cell line (HeLa) cell migration induced by thymidine 5'-O-monophosphorothioate analog. The stimulatory effect of TMPS was abolished by siRNA-mediated P2Y6 knockdown and diisothiocyanate derivative MRS 2578, a selective antagonist of the P2Y6R. Our results indicate for the first time that increased stability of thymidine 5'-O-monophosphorothioate as well as its affinity toward the P2Y6R may be responsible for some long-term effects mediated by this receptor.

Antibacterial and Antimetastatic Potential of Diospyros lycioides Extract on Cervical Cancer Cells and Associated Pathogens.

Cervical cancer is among the most prevalent forms of cancer in women worldwide. Diospyros lycioides was extracted using hexane, ethyl acetate, acetone, and methanol and finger print profiles were determined. The leaf material was tested for the presence of flavonoids, tannins, saponins, terpenoids, and cardiac glycosides using standard chemical methods and the presence of flavonoids and phenolics using thin layer chromatography. The total phenolic content was determined using Folin-Ciocalteu procedure. The four extracts were tested for antibacterial activity using bioautography against Staphylococcus aureus, Enterococcus faecalis, Pseudomonas aeruginosa, and Escherichia coli. The acetone extract with the highest number of antibacterial and antioxidant compounds was assessed for its cytotoxicity on BUD-8 cells using the real-time xCELLigence system and its potential effects on metastatic cervical cancer (HeLa) cell migration and invasion were assessed using wound healing migration and invasion assays. The leaf extract tested positive for flavonoids, tannins, and terpenoids while the four different extracts tested in the antimicrobial assay contained constituents active against one or more of the organisms tested, except E. coli. The cytotoxicity of the acetone extract in real-time was concentration-dependent with potent ability to suppress the migration and invasion of HeLa cells. The finding demonstrates the acetone extract to contain constituents with antibacterial and antimetastatic effects on cervical cancer cells.

MiR-346 Up-regulates Argonaute 2 (AGO2) Protein Expression to Augment the Activity of Other MicroRNAs (miRNAs) and Contributes to Cervical Cancer Cell Malignancy

MicroRNAs (miRNAs) are a class of post-transcriptional regulators of gene expression, and AGO2 is essential for miRNA activity. In this study, we focused on the regulation of AGO2 by miR-346 and the consequences in cervical cancer cells. miR-346 enhanced the expression of AGO2, resulting in the increased activity of other miRNAs and contributing to the malignancy of HeLa cells. GRSF1 participated in the regulation of AGO2 by miR-346, and the middle sequence of miR-346 was vital for the synergy effect of miR-346 and GRSF1. We determined that miR-346 promoted the migration and invasion of HeLa cells. In summary, we are the first to report that AGO2 is regulated positively by miRNA and that GRSF1 participates in the miRNA pathway.

MicroRNA-720 promotes in vitro cell migration by targeting Rab35 expression in cervical cancer cells.

BackgroundMicroRNA-720 (miR-720), a nonclassical miRNA, is involved in the initiation and progression of several tumors. In our previous studies, miR-720 was shown to be significantly upregulated in cervical cancer tissues compared with normal cervical tissues. However, the precise biological functions of miR-720, and its molecular mechanisms of action, are still unknown.ResultsMicroarray expression profiles, luciferase reporter assays, and western blot assays were used to validate Rab35 as a target gene of miR-720 in HEK293T and HeLa cells. The regulation of Rab35 expression by miR-720 was assessed using qRT-PCR and western blot assays, and the effects of exogenous miR-720 and Rab35 on cell migration were evaluated in vitro using Transwell® assay, wound healing assay, and real-time analyses in HeLa cells. The influences of exogenous miR-720 on cell proliferation were evaluated in vitro by the MTT assay in HeLa cells. In addition, expression of E-cadherin and vimentin associated with epithelial-mesenchymal transition were also assessed using western blot analyses after transfection of miR-720 mimics and Rab35 expression vectors. The results showed that the small GTPase, Rab35, is a direct functional target of miR-720 in cervical cancer HeLa cells. By targeting Rab35, overexpression of miR-720 resulted in a decrease in E-cadherin expression and an increase in vimentin expression and finally led to promotion of HeLa cell migration. Furthermore, reintroduction of Rab35 3′-UTR(−) markedly reversed the induction of cell migration in miR-720-expressing HeLa cells.ConclusionsThe miR-720 promotes cell migration of HeLa cells by downregulating Rab35. The results show that miR-720 is a novel cell migration-associated gene in cervical cancer cells.Electronic supplementary materialThe online version of this article (doi:10.1186/s13578-015-0047-5) contains supplementary material, which is available to authorized users.

TTBK2 with EB1/3 regulates microtubule dynamics in migrating cells through KIF2A phosphorylation.

Microtubules (MTs) play critical roles in various cellular events, including cell migration. End-binding proteins (EBs) accumulate at the ends of growing MTs and regulate MT end dynamics by recruiting other plus end-tracking proteins (+TIPs). However, how EBs contribute to MT dynamics through +TIPs remains elusive. We focused on tau-tubulin kinase 2 (TTBK2) as an EB1/3-binding kinase and confirmed that TTBK2 acted as a +TIP. We identified MT-depolymerizing kinesin KIF2A as a novel substrate of TTBK2. TTBK2 phosphorylated KIF2A at S135 in intact cells in an EB1/3-dependent fashion and inactivated its MT-depolymerizing activity in vitro. TTBK2 depletion reduced MT lifetime (facilitated shrinkage and suppressed rescue) and impaired HeLa cell migration, and these phenotypes were partially restored by KIF2A co-depletion. Expression of nonphosphorylatable KIF2A, but not wild-type KIF2A, reduced MT lifetime and slowed down the cell migration. These findings indicate that TTBK2 with EB1/3 phosphorylates KIF2A and antagonizes KIF2A-induced depolymerization at MT plus ends for cell migration.

Abstract 5296: FOXP1 expression is associated with tumor progression and poor prognosis in cervical cancer

Abstract Background: The forkhead box protein 1 (FOXP1) is considered as both a tumor suppressor candidate and a potential oncogene. Here, we investigated FOXP1 expression in cervical cancer, and the clinical significance of FOXP1 and it's mechanism of action in cervical cancer. Methods: To investigate the potential correlation between FOXP1 and various clinicopathologic parameters, we assessed the expression of FOXP1 in archival tumor tissue specimens from 158 patients with cervical cancer and 280 with cervical intraepithelial neoplasia as well as 378 matched nonadjacent normal tissues by immunohistochemical (IHC) staining. Subsequently, we studied the FOXP1's functional role by small interfering RNA (siRNA) approaches. Results: IHC staining demonstrated that FOXP1 expression increased during the normal to tumor transition of cervical carcinoma (P&amp;lt;0.001), and this increased expression was significantly associated with tumor stage (P = 0.009) and tumor grade (P&amp;lt;0.001). In multivariate analysis, FOXP1+ (P = 0.031) and tumor stage (P = 0.032) were independent prognostic factors for overall survival. FOXP1 knockdown by siRNA decreased cell proliferation, migration, and tumorigenesis in HeLa and CaSki cells. Conclusions: Taken together, our data indicate that FOXP1 has a crucial role in cervical cancer progression, and its overexpression is associated with poor prognosis, supporting that FOXP1 may be used as a promising novel target for therapeutic interventions. Citation Format: Hanbyoul Cho, Woo Kyeom Yang, Sol Kim, Ha-Yeon Shin, Eun Ju Lee, Jae-Hoon Kim. FOXP1 expression is associated with tumor progression and poor prognosis in cervical cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5296. doi:10.1158/1538-7445.AM2015-5296

Human papillomavirus 16 E6 modulates the expression of host microRNAs in cervical cancer

ObjectiveHuman papillomavirus (HPV) infection is a prerequisite of developing cervical cancer, approximately half of which are associated with HPV type 16. There are reports that HPV can disturb the expression pattern of host miRNAs, but its mechanism is not well understood. Materials and MethodsIn this study, we scanned 11 tumorigenesis related miRNAs in Hela cells that were overexpressed with HPV type 16 E6 protein. ResultsWe found the expression of miR-21 was upregulated by HPV type 16 E6 protein and meanwhile, the expression of miR-27a and miR-218 was downregulated. Furthermore, we identified that miR-21 overexpression could promote Hela and U2OS cells proliferation by targeting phosphatase-tensin homolog (PTEN), the result of which can be rescued by miR-21 inhibitor. In addition, E6 overexpression could also promote Hela cell migration and invasion. ConclusionOur results indicate that HPV infection and subsequent transformation take place through complex regulatory patterns of gene expression in the host cells, part of which are regulated by the E6 protein.

CDC42 Gtpase Activation Affects Hela Cell DNA Repair and Proliferation Following UV Radiation-Induced Genotoxic Stress.

Cell division control protein 42 (CDC42) homolog is a small Rho GTPase enzyme that participates in such processes as cell cycle progression, migration, polarity, adhesion, and transcription. Recent studies suggest that CDC42 is a potent tumor suppressor in different tissues and is related to aging processes. Although DNA damage is crucial in aging, a potential role for CDC42 in genotoxic stress remains to be explored. Migration, survival/proliferation and DNA damage/repair experiments were performed to demonstrate CDC42 involvement in the recovery of HeLa cells exposed to ultraviolet radiation-induced stress. Sub-lines of HeLa cells ectopically expressing the constitutively active CDC42-V12 mutant were generated to examine whether different CDC42-GTP backgrounds might reflect different sensitivities to UV radiation. Our results show that CDC42 constitutive activation does not interfere with HeLa cell migration after UV radiation. However, the minor DNA damage exhibited by the CDC42-V12 mutant exposed to UV radiation most likely results in cell cycle arrest at the G2/M checkpoint and reduced proliferation and survival. HeLa cells and Mock clones, which express endogenous wild-type CDC42 and show normal activity, are more resistant to UV radiation. None of these effects are altered by pharmacological CDC42 inhibition. Finally, the phosphorylation status of the DNA damage response proteins γ-H2AX and p-Chk1 was found to be delayed and attenuated, respectively, in CDC42-V12 clones. In conclusion, the sensitivity of HeLa cells to ultraviolet radiation increases with CDC42 over-activation due to inadequate DNA repair signaling, culminating in G2/M cell accumulation, which is translated into reduced cellular proliferation and survival.

Soybean Peptides Induce Apoptosis in HeLa Cells by Increasing Oxidative Stress

Soy proteins have been extensively studied because of its multiple health benefits. However, the effects of soy proteins on human cervical cancer cells are still unclear. Therefore, this study investigated the effects of soy proteins on HeLa cells and human fibroblasts by using soybean peptides (SPs). SPs selectively increased the generation of reactive oxygen species and apoptosis in HeLa cells but not in fibroblasts. In addition, SPs suppressed the migration of HeLa cells. Although the molecular mechanisms underlying the effects of SPs on human cervical cancer cells need to be investigated further, our findings provide insights on the therapeutic effects of soy protein on cervical cancer.

Quantitative Proteomics Analysis Reveals Novel Insights into Mechanisms of Action of Long Noncoding RNA Hox Transcript Antisense Intergenic RNA (HOTAIR) in HeLa Cells*

Long noncoding RNAs (lncRNAs), which have emerged in recent years as a new and crucial layer of gene regulators, regulate various biological processes such as carcinogenesis and metastasis. HOTAIR (Hox transcript antisense intergenic RNA), a lncRNA overexpressed in most human cancers, has been shown to be an oncogenic lncRNA. Here, we explored the role of HOTAIR in HeLa cells and searched for proteins regulated by HOTAIR. To understand the mechanism of action of HOTAIR from a systems perspective, we employed a quantitative proteomic strategy to systematically identify potential targets of HOTAIR. The expression of 170 proteins was significantly dys-regulated after inhibition of HOTAIR, implying that they could be potential targets of HOTAIR. Analysis of this data at the systems level revealed major changes in proteins involved in diverse cellular components, including the cytoskeleton and the respiratory chain. Further functional studies on vimentin (VIM), a key protein involved in the cytoskeleton, revealed that HOTAIR exerts its effects on migration and invasion of HeLa cells, at least in part, through the regulation of VIM expression. Inhibition of HOTAIR leads to mitochondrial dysfunction and ultrastructural alterations, suggesting a novel role of HOTAIR in maintaining mitochondrial function in cancer cells. Our results provide novel insights into the mechanisms underlying the function of HOTAIR in cancer cells. We expect that the methods used in this study will become an integral part of functional studies of lncRNAs.

Effect of bortezomib on migration and invasion in cervical carcinoma HeLa cell.

To explore the effect of bortezomib on migration and invasion of cervical carcinoma HeLa cell and specific molecular mechanism. The effect of bortezomib on the viability of HeLa cell was measured by MTT assay. The effect of bortezomib on cell migration and invasion was measured by Transwell assay and invasion experiment respectively. The activation of Akt/mTOR signaling pathway and expression level of MMP2, MMP9 were assayed by western blot. MTT assay indicated bortezomib (2.5μM, 5μM, 10μM) could inhibit HeLa cell viability, and the inhibitory rate was highest at 48h. Transwell assay and invasion experiment results showed that bortezomib inhibited HeLa cell migration and invasion. Western blotting assays presented bortezomib could suppress the phosphorylation of Akt and mTOR, and down-regulate the expression of MMP2 and MMP9. These results suggested bortezomib could inhibit migration and invasion in cervical carcinoma HeLa cell, which might be related to Akt/mTOR signal pathway.

Down-regulation of microRNA-9 leads to activation of IL-6/Jak/STAT3 pathway through directly targeting IL-6 in HeLa cell.

MicroRNA‐9 (miR‐9) presents to exert distinct and even opposite functions in different kinds of tumors through targeting different cellular genes. However, its role in cervical adenocarcinoma remains uncertain. Here, we report that miR‐9 is down‐regulated in cervical adenocarcinoma due to its frequent promoter‐hypermethylation and exerts its tumor suppressor role through inhibiting several novel target genes, including interleukin‐6 (IL‐6). The promoters of miR‐9 precursors (mir‐9‐1, ‐2, and ‐3) were hypermethylated in cervical adenocarcinoma tissues. Demethylation treatment of HeLa dramatically increased the expression of mature miR‐9. Both in vitro and in vivo functional experiments confirmed that miR‐9 can inhibit the proliferation, migration, and malignant transformation abilities of HeLa cells. Bioinformatics methods and array‐based RNA expression profiles were used to screen the downstream target genes of miR‐9. Dual‐luciferase reporting assay, real‐time qPCR, and ELISA or Western blot confirmed four genes (CKAP2, HSPC159, IL‐6, and TC10) to be novel direct target genes of miR‐9. Pathway annotation analysis of the differently expressed genes (DEGs) induced by ectopic miR‐9 expression revealed the enrichment in Jak/STAT3 pathway, which is one of the downstream pathways of IL‐6. Ectopic expression of miR‐9 in HeLa inhibited Jak/STAT3 signaling activity. Moreover, such effect could be partially reversed by the addition of exogenous IL‐6. In conclusion, our results here present a tumor suppressor potential of miR‐9 in cervical adenocarcinoma for the first time and suggest that miR‐9 could repress tumorigenesis through inhibiting the activity of IL‐6/Jak/STAT3 pathway. © 2015 The Authors. Molecular Carcinogenesis, published by Wiley Periodicals, Inc.

IKKβ/NF-κB mediated the low doses of bisphenol A induced migration of cervical cancer cells

Cervical cancer is considered as the second most common female malignant disease. There is an urgent need to illustrate risk factors which can trigger the motility of cervical cancer cells. Our present study revealed that nanomolar concentration of bisphenol A (BPA) significantly promoted the in vitro migration and invasion of cervical cancer HeLa, SiHa, and C-33A cells. Further, BPA treatment increased the expression of metalloproteinase-9 (MMP-9) and fibronectin (FN) in both HeLa and SiHa cells, while did not obviously change the expression of MMP-2, vimentin (Vim) or N-Cadherin (N-Cad). BAY 11-7082, the inhibitor of NF-κB, significantly abolished BPA induced up regulation of FN and MMP-9 in cervical cancer cells. While the inhibitors of PKA (H89), ERK1/2 (PD 98059), EGFR (AG1478), or PI3K/Akt (LY294002) had no effect on the expression of either FN or MMP-9. BPA treatment rapidly increased the phosphorylation of both IκBα and p65, stimulated nuclear translocation, and up regulated the promoter activities of NF-κB. The BPA induced up regulation of MMP-9 and FN and activation of NF-κB were mediated by phosphorylation of IKKβ via PKC signals. Collectively, our study found for the first time that BPA stimulated the cervical cancer migration via IKK-β/NF-κB signals.

Curcumin and emodin down-regulate TGF-β signaling pathway in human cervical cancer cells.

Cervical cancer is the major cause of cancer related deaths in women, especially in developing countries and Human Papilloma Virus infection in conjunction with multiple deregulated signaling pathways leads to cervical carcinogenesis. TGF-β signaling in later stages of cancer is known to induce epithelial to mesenchymal transition promoting tumor growth. Phytochemicals, curcumin and emodin, are effective as chemopreventive and chemotherapeutic compounds against several cancers including cervical cancer. The main objective of this work was to study the effect of curcumin and emodin on TGF-β signaling pathway and its functional relevance to growth, migration and invasion in two cervical cancer cell lines, SiHa and HeLa. Since TGF-β and Wnt/β-catenin signaling pathways are known to cross talk having common downstream targets, we analyzed the effect of TGF-β on β-catenin (an important player in Wnt/β-catenin signaling) and also studied whether curcumin and emodin modulate them. We observed that curcumin and emodin effectively down regulate TGF-β signaling pathway by decreasing the expression of TGF-β Receptor II, P-Smad3 and Smad4, and also counterbalance the tumorigenic effects of TGF-β by inhibiting the TGF-β-induced migration and invasion. Expression of downstream effectors of TGF-β signaling pathway, cyclinD1, p21 and Pin1, was inhibited along with the down regulation of key mesenchymal markers (Snail and Slug) upon curcumin and emodin treatment. Curcumin and emodin were also found to synergistically inhibit cell population and migration in SiHa and HeLa cells. Moreover, we found that TGF-β activates Wnt/β-catenin signaling pathway in HeLa cells, and curcumin and emodin down regulate the pathway by inhibiting β-catenin. Taken together our data provide a mechanistic basis for the use of curcumin and emodin in the treatment of cervical cancer.

Down-regulation of Frizzled-7 expression inhibits migration, invasion, and epithelial-mesenchymal transition of cervical cancer cell lines.

Frizzled-7 (FZD7) has been demonstrated as a critical receptor of the Wnt signaling and involves in tumorigenesis and metastasis in many cancer types. However, limited information was found in cervical cancer. The aim of this study was to investigate the functional role of FZD7 in migration, invasion, and epithelial-mesenchymal transition (EMT) of cervical cancer cells. HeLa and SiHa cervical carcinoma cell lines with FZD7 expression were chosen in this study. A short hairpin RNA (shRNA) construct targeting FZD7 mRNA was transfected into HeLa and SiHa cells, and the stably transfected cell lines were obtained through G418 screening. Functional experiments were further performed to assess whether FZD7 down-regulation affects the migration, invasion, and EMT of HeLa and SiHa cells. Our results revealed that down-regulation of FZD7 expression significantly inhibited cell invasion and migration, as well as decreased the expression and activities of MMP2 and MMP9 in both cell types. Additionally, FZD7 silencing resulted in down-regulation of mesenchymal markers including Vimentin and Snail while increased the levels of epithelial marker E-cadherin. We further found that decreased FZD7 expression inhibited the phosphorylation levels of JNK and c-jun in both HeLa and SiHa cells, as determined by Western blot analysis and immunofluorescence. Overall, our results indicate that shRNA-mediated knockdown of FZD7 inhibits invasion, metastasis, and EMT of cervical cancer cells. FZD7 may provide a promising therapeutic target in cervical cancer.