Cervical Cancer Cell Proliferation Research Articles

The Role of ZNF275/AKT Pathway in Carcinogenesis and Cisplatin Chemosensitivity of Cervical Cancer Using Patient-Derived Xenograft Models

Zinc finger protein 275 (ZNF275) is a C2H2-type transcription factor that is localized on chromosome Xq28. Whether ZNF275 participates in modulating the biological behaviors of cervical cancer has not been determined to our knowledge. The present study employed CCK-8, BrdU, flow cytometry, and a transwell assay to investigate the cell viability, proliferation, apoptosis, migration, and invasion of cervical cancer cells. The application of Western blotting and immunohistochemistry (IHC) aims to assess ZNF275 protein expression and identify the signaling pathway relevant to ZNF275-mediated effects on cervical cancer. The therapeutic impact of the combined therapy of the AKT inhibitor triciribine and cisplatin was evaluated on cervical cancer patient-derived xenograft (PDX) models expressing high ZNF275. The current research illustrated that cervical cancer tissue exhibited a higher expression of ZNF275 in contrast to the surrounding normal cervical tissue. The downregulation of ZNF275 suppressed cell viability, migration, and invasion, and facilitated the apoptosis of SiHa and HeLa cells via weakening AKT/Bcl-2 signaling pathway. Moreover, triciribine synergized with cisplatin to reduce cell proliferation, migration, and invasion, and enhanced the apoptosis of SiHa cells expressing high ZNF275. In addition, the combination treatment of triciribine and cisplatin was more effective in inducing tumor regression than single agents in cervical cancer PDX models expressing high ZNF275. Collectively, the current findings demonstrated that ZNF275 serves as a sufficiently predictive indicator of the therapeutic effectiveness of the combined treatment of triciribine and cisplatin on cervical cancer. Combining triciribine with cisplatin greatly broadens the therapeutic options for cervical cancer expressing high ZNF275, but further research is needed to confirm these results.

Jagged1 contained in MSC-derived small extracellular vesicles promotes squamous differentiation of cervical cancer by activating NOTCH pathway

PurposeCervical cancer is the fourth most common cancer in women and poses a major threat to women's health, urgently requiring new treatment methods.MethodsThis study first successfully extracted and identified small extracellular vesicles secreted by human umbilical cord-derived mesenchymal stem cells. We studied the effects of MSC-sEV on the squamous differentiation levels of cervical cancer CaSki cells in vitro, and explored the effects of MSC-sEV on the NOTCH pathway, the growth, proliferation, migration abilities and squamous differentiation levels of cervical cancer cells. The roles of MSC-sEV were also verified in human keratinocyte HaCaT cells.ResultsThe results showed that Jagged1 protein on MSC-sEV can bind to NOTCH1 on cervical cancer cells, activate NOTCH signaling, and promote squamous differentiation levels in CaSki cells, thus inhibiting the growth, proliferation and migration abilities of CaSki cells. MSC-sEV can also activate the NOTCH pathway in HaCaT cells, but promote the viability of HaCaT cells.ConclusionMSC-sEV can activate the NOTCH pathway to promote squamous differentiation of CaSki cells and inhibit the growth proliferation and migration abilities of CaSki cells which may be a new mechanism for cervical cancer treatment.

Human papillomavirus type 16 E6 promotes cervical cancer proliferation by upregulating transketolase enzymatic activity through the activation of protein kinase B.

Over 99% of precancerous cervical lesions are associated with human papillomavirus (HPV) infection, with HPV types 16 and 18 (especially type 16) found in over 70% of cervical cancer cases globally. E6, a critical HPV gene, triggers malignant proliferation by degrading p53; however, this mechanism alone cannot fully explain the oncogenic effects of HPV16 E6. Therefore, we aimed to investigate new targets of HPV oncogenic mechanisms. Our results revealed significant changes in nonoxidative pentose phosphate pathway (PPP) metabolites in HPV16-positive cells. However, the role of nonoxidative PPP in HPV-associated cell transformation and tumor development remained unexplored. In this study, we investigated the impact and mechanisms of HPV16 E6 on cervical cancer proliferation using the HPV-negative cervical cancer cell line (C33A). HPV16 E6 was found to promote cervical cancer cell proliferation both in vitro and in vivo, activating the nonoxidative PPP. Transketolase (TKT), a key enzyme in the nonoxidative PPP, is highly expressed in cervical cancer tissues and associated with poor prognosis. HPV16 E6 promotes cervical cancer cell proliferation by upregulating TKT activity through the activation of AKT. In addition, oxythiamine (OT), a TKT inhibitor, hindered tumor growth, with enhanced effects when combined with cisplatin (DDP). In conclusion, HPV16 E6 promotes cervical cancer proliferation by upregulating TKT activity through the activation of AKT. OT demonstrates the potential to inhibit HPV16-positive cervical cancer growth, and when combined with DDP, could further enhance the tumor-suppressive effect of DDP.

CBX7 is involved in the progression of cervical cancer throughthe ITGβ3/TGFβ1/AKT pathway.

The chromobox protein homolog 7 (CBX7) serves a tumor-suppressive role in human malignant neoplasias. The downregulation of CBX7 is associated with the poor prognosis and aggressiveness of various human cancers. However, the biological functions and underlying mechanisms of CBX7 in cervical cancer remain unclear. The present study investigated the role and mechanism of CBX7 in cervical cancer. Lentivirus and siRNA were used to construct cervical cancer cells with stable CBX7 knockdown and SiHa xenograft models. The cell growth, migration, invasion and apoptosis were observed through in vivo and in vitro experiments. The expression levels of CBX7, integrin β3 (ITGβ3), transforming growth factor β1 (TGFβ1), phosphatidylinositol-3-kinase (PI3K), AKT, E-cadherin (E-cad) and vimentin (VIM) were detected by western blot analysis and reverse transcription-quantitative PCR. The correlation between CBX7 and these genes was analyzed. TGFβ1 was also silenced through shRNA in cells with stable CBX7 knockdown to detect its effect on cell growth, invasion and apoptosis, and on pathway-related gene expression. It was revealed that knockdown of CBX7 promoted the proliferation, migration, and invasion of cervical cancer cells, and inhibited apoptosis. In addition, CBX7 knockdown promoted tumor growth in vivo. Correlation analysis demonstrated that CBX7 was negatively correlated with ITGβ3, TGFβ1, PI3K, AKT, phosphorylated AKT and VIM, but positively correlated with E-cad. Moreover, the knockdown of TGFβ1 reversed the promotion of cell proliferation and inhibition of apoptosis induced by CBX7 knockdown and attenuated the increase of ITGβ3, TGFβ1, PI3K, AKT and VIM caused by CBX7 knockdown. In conclusion, the findings of the present study indicated that the downregulation of CBX7 enhances cell migration and invasion while inhibiting cell apoptosis in cervical cancer by modulating the ITGβ3/TGFβ1/AKT signaling pathways.

Stratifin (SFN) Regulates Cervical Cancer Cell Proliferation, Apoptosis, and Cytoskeletal Remodeling and Metastasis Progression Through LIMK2/Cofilin Signaling

The aberrant expression of Stratifin (SFN) is intricately associated with the initiation and progression of numerous tumors. This study aims to investigate whether SFN regulates the metastasis of cervical cancer cells through the LIMK2/Cofilin signaling pathway. In this study, we compared the expression of SFN in normal cervical tissues and cervical carcinoma tissues. We established SFN overexpression and SFN silencing cellular models to assess the invasive and migratory capabilities of cervical cancer cells using transwell and scratch assays. YO-PRO-1/PI and EdU staining were employed to evaluate apoptotic and proliferative capacities, while Actin-Tracker Green-488 was utilized to investigate cytoskeletal remodeling. The expression levels of SFN, LIMK2, p-LIMK2, Cofilin, and p-Cofilin were examined through Western blotting and immunofluorescence. Our findings revealed elevated expression of SFN in cervical squamous cell carcinoma tissues. SFN overexpression was observed to enhance invasion and migration of cervical cancer cells, induce cytoskeletal remodeling, facilitate cell proliferation, and suppress apoptosis. Furthermore, SFN overexpression upregulated the expression levels of LIMK2, p-LIMK2, Cofilin, and p-Cofilin. Conversely, silencing SFN exerted opposite effects. SFN plays an important role in the diagnosis of cervical cancer. SFN can regulate cervical cancer cell proliferation, apoptosis, cytoskeletal remodeling and metastasis through LIMK2/Cofilin signaling.

Studying the Role of miR-141 in Supporting Cervical Cancer Cell Proliferation

MicroRNAs (miRNAs) are small noncoding RNA, approximately 18-23 nucleotides that can post-transcriptionally regulate the expression of complementary mRNAs. MiRNAs have been found to play a critical role in a broad spectrum of biological processes, such as developmental timing, cell death, cell proliferation, hematopoiesis, and nervous system patterning. Here, we aimed to investigate the possible upregulation of miR-141 in cervical cancer cells and to confirm the influential role of miR-141 in cervical cancer cell proliferation. The level of miR-141 in HeLa cells has been assessed using quantitative real-time PCR (qRT-PCR). Cell morphology and a number of living HeLa cells were achieved upon transfection with either precursor miR-141 (pre-miR-141) or a specific inhibitor. MTT assay and lactate dehydrogenase (LDH) production were monitored to assess the potential toxic effect of miR-141 in cancer cells. ELISA assay has been used to monitor the produced cytokines from transfected HeLa cells. Notably, the expression of miR-141 significantly increased in HeLa cells compared to the normal cervical HCK1T cell line. Transfection of HeLa cells with an inhibitor, antagonist miR-141, showed a potent effect on cancer cell viability, unlike the transfection of pre-miR-141. HeLa cells transfected with pre-miR-141 showed decreased levels of interleukin 13 (IL-13). Meanwhile, the transfection of miR-141 specific inhibitor showed an increasing level of produced IL-10 and a decreasing level of IL-10, indicating the role of miR-141 in avoiding programmed cell death in HeLa cells. Together, these data uncover the role of miR-141 in supporting cervical cancer progression and provide miR-141 as a believable therapeutic target.

9-oxo-ODAs suppresses the proliferation of human cervical cancer cells through the inhibition of CDKs and HPV oncoproteins

Mucosal human papillomavirus (HPV) subtypes 16 and 18 are causative agents of cervical cancer, a leading cause of cancer-related deaths among women worldwide. In Japan, eggplant calyx is a folk remedy used to treat common warts. 9-oxo-(10E,12E)-octadecadienoic acid, isolated from eggplant calyx, may have antitumor effects. This study investigated the antitumor effects of 9-oxo-(10E, 12Z)-octadecadienoic acid and 9-oxo-(10E,12E)-octadecadienoic acid (9-oxo-ODAs) on human cervical cancer cells. 9-oxo-ODAs suppressed the proliferation of human cervical cancer cell lines (HeLa, and SiHa) in a concentration-dependent manner (IC50 = 25–50 µM). FCM analysis revealed that 9-oxo-ODAs induced apoptosis. Transcriptome, proteomics, and enrichment analyses revealed that treatment with 9-oxo-ODAs significantly altered the cell cycle and p53 pathways and decreased cyclin-dependent kinase 1 (CDK1) protein expression. Real-time PCR analysis demonstrated that 9-oxo-ODAs reduced CDK1 mRNA expression in a concentration-dependent manner. In vitro, 9-oxo-ODAs reduced the HPV oncoprotein expression. In ex vivo human cervical cancer tissues, 9-oxo-ODAs decreased CDK1 expression and increased cleaved caspase 3, an apoptosis marker. Further, 9-oxo-ODAs showed the potential to suppressed metastatic formation and growth of cervical cancer in vivo. These findings suggest that 9-oxo-ODAs induce cell cycle arrest and apoptosis in HPV-positive human cervical cancer cells, and this process involves CDK1. Consequently, 9-oxo-ODAs may be potential therapeutic agents for cervical cancer.

Revisiting the role of endogenous STAT3 in HPV-positive cervical cancer cells.

Novel treatment options for human papillomavirus (HPV)-induced cancers are urgently required. The oncogenic transcription factor signal transducer and activator of transcription 3 (STAT3) is considered to be constitutively active in HPV-positive cervical cancer cells and essential for their proliferation. Moreover, STAT3 was reported to undergo mutually stimulatory interactions with the HPV E6/E7 oncogenes. Thus, inhibiting STAT3 in HPV-positive cancer cells is under discussion to provide a powerful novel therapeutic strategy. We here show that the antifungal drug ciclopirox destabilizes the STAT3 protein by acting as an iron chelator. However, by exploring the functional consequences of STAT3 inhibition in HPV-positive cancer cells, we obtained several unexpected results. Chemical STAT3 inhibitors heterogeneously affect cervical cancer cell proliferation and those which act antiproliferative also block the growth of STAT3 knockout cells, indicating induction of off-target effects. In contrast to several chemical inhibitors, genetic inhibition of STAT3 expression by either RNA interference or the CRISPR/Cas9 method does not appreciably affect cervical cancer cell proliferation. Transcriptome analyses indicate that blocking STAT3 expression in HPV-positive cancer cells has very limited effects on putative STAT3 target genes. Although the targeted inhibition of specific growth-promoting signaling pathways leads to a feedback activation of STAT3 in cervical cancer cells via Janus kinase1/2, this does not lead to treatment resistance. Moreover, we did not obtain experimental evidence for a STAT3-linked activation of HPV E6/E7 oncogene expression or, vice versa, an E6/E7-dependent activation of STAT3, at endogenous conditions in cervical cancer cells. Collectively, these findings question the essential role of STAT3 in cervical cancer cell proliferation and the strategy to inhibit STAT3 in these cells for therapeutic purposes.

Retracted] Tripartite motif‑containing 14 regulates cell proliferation and apoptosis in cervical cancer via the Akt signaling pathway.

Following the publication of this paper, it was drawn to the Editor's attention by a concerned reader that the GAPDH control western blotting data shown in Fig.2B were strikingly similar to data appearing in different form in Fig.1E in another article written by different authors at different research institutes [LiangT, Ye X, Liu Y, Qiu X, Li Z, TianB and YanD: FAM46B inhibits cell proliferation and cell cycle progression in prostate cancer through ubiquitination of β‑catenin. Exp Mol Med50: 1‑12, 2018]. Owing to the fact that the contentious data in the above article had already been published prior to its submission to Molecular Medicine Reports, the Editor has decided that this paper should be retracted from the Journal. The authors were asked for an explanation to account for these concerns, but the Editorial Office did not receive a reply. The Editor apologizes to the readership for any inconvenience caused. [Molecular Medicine Reports 22: 5145‑5154, 2020; DOI: 10.3892/mmr.2020.11634].

Circ_0000337 Promotes the Progression of Cervical Cancer by miR-155-5p/RAB3B Axis.

Current study aims to investigate the biological function of circular RNA (circRNA, circ_0000337) in cervical cancer (CC). Bioinformatic analyses were used to predict targets for circ_0000337 and miR-155-5p, and analyze the gene expression differences between cervical squamous cell carcinoma and endocervical adenocarcinoma (CESC) tissues and normal tissues. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot were applied to assess mRNA and protein expressions of circ_0000337, microRNA-155-5p (miR-155-5p) and member RAS oncogene family (RAB3B), respectively. Following the establishment of gain/loss-of-function models, CCK-8 was performed to evaluate cell proliferation. Bioinformatics analysis, dual-luciferase reporter assay and RNA immunoprecipitation (RIP) were used to identify the interaction in circ_0000337, miR-155-5p, and RAB3B. Circ_0000337 and RAB3B were upregulated, while miR-155-5p was downregulated in CC tissues and cell lines. circ_0000337 overexpression promoted cell proliferation, circ_0000337 knock down inhibited cell proliferation by sponging miR-155-5p. RAB3B was a target of miR-155-5p which was positively regulated by circ_0000337. In the collected CC tissues, there was a negative correlation between miR-155-5p and circ_0000337 or RAB3B, and a positive correlation between circ_0000337 and RAB3B. miR-155-5p was positively, while RAB3B was negatively correlated with OS in patients with CC, and they were negatively correlated. In conclusion, circ_0000337 upregulates RAB3B by sponging miR-155-5p to promote CC cell proliferation.

Analysis of the expression and mechanism of follistatin‑like protein 1 in cervical cancer.

The abnormal expression of follistatin‑like protein1 (FSTL1) in various tumors is a crucial regulator of the biological process of tumorigenesis. Nonetheless, the regulatory role of FSTL1 in cervical cancer is yet to be elucidated. Hence, the present study aimed to explore the expression, function, and molecular mechanism of FSTL1 in cervical cancer. The expression of FSTL1 in normal and cervical cancer tissues was examined using quantitative reverse transcription‑polymerase chain reaction and immunohistochemistry assays. The effects of abnormal expression of FSTL1 on cervical cancer cells were assessed using colony formation, MTT, wound‑healing, Transwell, apoptosis, and nude mouse tumorigenicity assays. FSTL1‑related molecular mechanisms were screened using gene chip analysis. Western blotting analysis was used to verify the regulatory mechanisms of FSTL1 in cervical cancer. The results indicated that the expression of FSTL1 was downregulated in cervical cancer tissues and that its downregulation was associated with tumor differentiation, pathologic type, and infiltration depth. Moreover, FSTL1 inhibited the proliferation, migration, and invasion of cervical cancer cells as well as xenograft tumor growth and promoted cell apoptosis. In addition, the findings of gene chip analysis suggested that the differentially expressed genes of FSTL1 were predominantly enriched in multiple signaling pathways, of which the insulin‑like growth factor (IGF)‑1 signaling pathway was significantly activated. Western blotting suggested the involvement of FSTL1 in the regulation of the IGF‑1R/PI3K/AKT/BCL‑2 signaling pathway. These data establish the downregulation of FSTL1 in cervical cancer tissues. FSTL1 inhibited the proliferation, migration, and invasion of cervical cancer cells and promoted their apoptosis. Furthermore, xenograft tumor growth in nude mice was inhibited. FSTL1 may be involved in the regulation of the IGF‑1R/PI3K/AKT/BCL‑2 signaling pathway in cervical cancer. Therefore, FSTL1 may be employed as a novel biomarker to determine the extent of disease progression in patients with cervical cancer.

Histone acetyltransferase CSRP2BP promotes the epithelial–mesenchymal transition and metastasis of cervical cancer cells by activating N-cadherin

BackgroundDysregulated epithelial–mesenchymal transition (EMT) is involved in cervical cancer metastasis and associated with histone acetylation. However, the underlying molecular mechanisms of histone acetylation in cervical cancer EMT and metastasis are still elusive.MethodsWe systematically investigated the expression patterns of histone acetylation genes and their correlations with the EMT pathway in cervical cancer. The expression of CSRP2BP among cervical cancer tissues and cell lines was detected using Western blotting and immunohistochemistry analyses. The effects of CSRP2BP on cervical cancer cell proliferation and tumorigenicity were examined by cell growth curve, EdU assay, flow cytometry and xenotransplantation assays. Wound healing assays, transwell migration assays and pulmonary metastasis model were used to evaluate the effects of CSRP2BP on cell invasion and metastasis of cervical cancer cells in vivo and in vitro. RNA-seq, chromatin immunoprecipitation (ChIP), co-immunoprecipitation (Co-IP) and luciferase reporter assays were used to uncover the molecular mechanisms of CSRP2BP in promoting cervical cancer EMT and metastasis.ResultsWe prioritized a top candidate histone acetyltransferase, CSRP2BP, as a key player in cervical cancer EMT and metastasis. The expression of CSRP2BP was significantly increased in cervical cancer tissues and high CSRP2BP expression was associated with poor prognosis. Overexpression of CSRP2BP promoted cervical cancer cell proliferation and metastasis both in vitro and in vivo, while knockdown of CSRP2BP obtained the opposite effects. In addition, CSRP2BP promoted resistance to cisplatin chemotherapy. Mechanistically, CSRP2BP mediated histone 4 acetylation at lysine sites 5 and 12, cooperated with the transcription factor SMAD4 to bind to the SEB2 sequence in the N-cadherin gene promotor and upregulated N-cadherin transcription. Consequently, CSRP2BP promoted cervical cancer cell EMT and metastasis through activating N-cadherin.ConclusionsThis study demonstrates that the histone acetyltransferase CSRP2BP promotes cervical cancer metastasis partially through increasing the EMT and suggests that CSRP2BP could be a prognostic marker and a potential therapeutic target for combating cervical cancer metastasis.

ANXA3, associated with YAP1 regulation, participates in the proliferation and chemoresistance of cervical cancer cells.

Cervical cancer, as one of the most common cancers in women, remains a major health threat worldwide. Annexin A3 (ANXA3), a component of the annexin family, is upregulated in numerous cancers, with no explicit role in cervical cancer. This study aims to investigate the function of ANXA3 in cervical cancer. Differential expression genes between the cervical cancer tissues of patients and the controls were analyzed in The Cancer Genome Atlas (TCGA) and Gene Expression Profiling Interactive Analysis (GEPIA) database. Using transfection approaches to either upregulate or downregulate ANXA3, its role in cell proliferation and chemosensitivity of human cervical cancer cell lines (HeLa and C33A) was evaluated. Furthermore, the binding activity between YAP1 and ANXA3 was also explored. Genomics analysis indicated that differential genes were mostly associated with cell cycle progression and DNA replication. ANXA3 was highly expressed in the cervical cancer tissues and closely linked to malignancy degree. Knockdown of ANXA3 in cervical cancer cells inhibited cell cycle progression. A similar result was observed in the reduction of cyclin D, CDK4, cyclin E, and CDK2 in cervical cancer cells with ANXA3 silencing. Cervical cancer cells obtained high sensitivity to cisplatin (DDP) when ANXA3 was downregulated. Conversely, these capabilities were the opposite in cervical cancer cells overexpressing ANXA3. Furthermore, the expression levels of ANXA3 and YAP1 were positively correlated. YAP1 upregulation was positively connected with malignant behaviors, which were reversed by ANXA3 downregulation. In light of our findings, targeting ANXA3 expressed in cervical cancer might contribute to more potential therapeutic strategies.

Transglutaminase 3 suppresses proliferation and cisplatin resistance of cervical cancer cells by inactivation of the PI3K/AKT pathway.

Recent studies have shown that dysregulation of transglutaminase 3 (TGM3) is related to the aggressive progression of several cancer types. Our study aimed to determine the function of TGM3 in cervical cancer (CC) tumorigenesis. Gene expression profiles GSE63514, GSE9750, GSE46857 and GSE67522 were obtained from the Gene Expression Omnibus (GEO) database. Overlapping differential expressed genes (DEGs) in CC were screened using GEO2R online tool and Venn diagram software. The Kaplan-Meier plotter was used to determine overall survival. TGM3 expression was analyzed based on GEO and The Cancer Genome Atlas (TCGA) databases, qRT-PCR and western blot analyses. Cell proliferation was evaluated by CCK-8 and EdU incorporation assays. The half-maximal inhibitory concentration (IC50) value of cisplatin and cell apoptosis was assessed by CCK-8 and TUNEL assays, respectively. P-glycoprotein (P-gp) expression and the changes of phosphatidylinositol 3-kinase (PI3K)/protein kinase B (Akt) pathway were examined using western blot analysis. We identified 3 overlapping DEGs, including TGM3, glutathione peroxidase 3 (GPX3), and alpha B-crystallin (CRYAB), which were downregulated in CC tissues. TGM3 expression was reduced in CC cells and related to the poor prognosis of CC patients. TGM3 overexpression retarded the proliferation, reduced IC50 value of cisplatin, accelerated cisplatin-induced apoptosis, and inhibited cisplatin-induced P-gp level in CC cells. Furthermore, TGM3 overexpression suppressed the PI3K/Akt pathway in CC cells. Moreover, treatment with 740Y-P, a PI3K activator, abolished the effect of TGM3 overexpression on proliferation and cisplatin resistance in CC cells. In conclusion, overexpression of TGM3 suppressed proliferation and cisplatin resistance in CC cells by blocking the PI3K/Akt pathway.

Hsa_Circ_0000021 Sponges miR-3940-3p/KPNA2 Expression to Promote Cervical Cancer Progression.

Circular RNAs (circRNAs) have a vital role in the occurrence of numerous cancers. However, its function and pattern of expression in cervical cancer (CC) remain unclear. This research aims to investigate the hsa_circ_000002's regulatory mechanism in CC. Hsa_circ_0000021, miR-3940-3p, and KPNA2 expression levels were estimated through qRT-PCR. Nuclear/cytoplasmic separation was conducted to find the subcellular location of hsa_circ_0000021. Western blot was done to estimate the levels of KPNA2 protein. CCK-8, BrdU, wound healing, transwell, and tumor xenograft assays were performed to study how hsa_circ_0000021/miR-3940-3P/KPNA2 function affect CC. Hsa_circ_0000021's targeting relationships with miR-3940-3p and KPNA2 were ascertained through RIP and luciferase experiments. Hsa_circ_0000021 and KPNA2 were overexpressed and inversely associated with the levels of miR-3940-3p in CC. Knocking down either hsa_circ_0000021 or KPNA2 repressed the growth of CC tumors as well as the proliferation, invasion, and migration of CC cells. Silencing miR-3940-3p promoted the malignant proliferation of CC cells. Regarding its mechanism, hsa_circ_0000021 affected the malignant CC cell proliferation via the sponging of miR-3940-3p, which targeted KPNA2. Hsa_circ_0000021 regulates the miR-3940-3p/KPNA2 axis to promote CC occurrence. This potentially is a novel target for CC treatment.

ATG9A modulated by miR-195-5p can boost the malignant progression of cervical cancer cells

ABSTRACT Cervical cancer (CC) is a major public health problem, and its molecular mechanism requires further investigation. The goal of this study was to determine the role of miR-195-5p and the autophagy-related protein ATG9A in tumour metastasis, epithelial – mesenchymal transition (EMT), apoptosis, and autophagy of CC cells. Using bioinformatics analysis, we predicted ATG9A as a downstream target gene of miR-195-5p, an integral membrane protein required for autophagosome formation and involved in tumorigenesis. Next, western blotting and Quantitative Real-Time Polymerase Chain Reaction (qRT-PCR) showed that upregulation of miR-195-5p decreased protein and mRNA expression of ATG9A, and downregulation of miR-195-5p promoted ATG9A protein and mRNA expression. In addition, detection of the dual luciferase reporter gene further indicated ATG9A is a direct downstream target gene of miR-195-5p. Finally, the effects of miR-195-5p and ATG9A on CC cell proliferation, migration, invasion, EMT, autophagy, and apoptosis were evaluated in vitro. Our results showed that upregulation of miR-195-5p not only inhibits proliferation, migration, and the EMT of CC cells, but also induces apoptosis and autophagy. Conversely, downregulation of miR-195-5p increased malignant metastasis and the EMT of CC cells, and inhibited apoptosis as well as autophagy. In addition, miR-195-5p targeted and negatively regulated ATG9A, and rescue experiments suggested that overexpression of ATG9A could partially abolish miR-195-5p-mediated suppression of CC cells. Our findings improve our understanding of the mechanism of action of miR-195-5p in the malignant behaviour of CC. miR-195-5p is likely to be a promising cancer suppressor gene, which provides clinical evidence for targeted therapy of CC.

Knockdown of PAF1 reduces cervical cancer cell proliferation, migration and invasion via retarding FLOT2-mediated MEK/ERK1/2 pathway

ABSTRACT Cervical cancer (CC) is a very usual reproductive malignant tumor in women. RNA polymerase II-associated factor 1 (PAF1) and flotillin-2 (FLOT2) both have been discovered to key participators in cancers’ progression. However, the effects of PAF1/FLOT2 axis on CC development have not been probed. In this study, PAF1 and FLOT2 exhibited higher expression, and silencing of PAF1 down-regulated FLOT2 expression in CC. In addition, the regulatory effects of PAF1 suppression on CC progression were reversed after FLOT2 overexpression. Next, inhibition of PAF1 slowed the tumor growth in vivo through modulating FLOT2. Besides, down-regulation of PAF1 reduced FLOT2 expression to retard the MEK/ERK1/2 pathway. In conclusion, knockdown of PAF1 suppressed CC progression via retarding FLOT2-mediated MEK/ERK1/2 pathway. Our findings illustrated that the PAF1/FLOT2 axis may be useful bio-targets for CC treatment.

Panobinostat (LBH589) combined with AM1241 induces cervical cancer cell apoptosis through autophagy pathway

PurposeThe study aims to investigate the apoptotic effects of combining LBH589 and AM1241 (a selective CB2 receptor agonist) on cervical cancer cells and elucidating the mechanism of this combined therapy, which may provide innovative strategies for treating this disease.MethodsThe viability of the cervical cancer cells was measured by cell counting kit-8 (CCK-8) assay, and the synergistic effect was analyzed using SynergyFinder. Cell proliferation was tested by cell cloning. The apoptosis and reactive oxygen species (ROS) production in cervical cancer cells were analyzed by flow cytometry. Western blot and quantitative real-time PCR (qRT-PCR) were employed to determine changes in protein and gene levels of pathway-related factors.ResultsBy the results of cytotoxicity assay, SiHa cells were selected and treated with 0.1 μM LBH589 and 4 μM AM1241 for 24 h for subsequent experiments. The combination of both was synergistic as determined by bliss, ZIP, HSA and LOEWE synergy score. Plate cloning results showed that LBH589 combined with AM1241 inhibited the proliferation of cervical cancer cells compared to individual drug. Additionally, compared with LBH589 alone, the combination of LBH589 and AM1241 induced autophagy by increasing LC3II/LC3I and decreasing P62/GAPDH, leading to a significantly higher rate of apoptosis. Pharmacological inhibition of also inhibited apoptosis. Consistently, we found that the endoplasmic reticulum, DNA damage repair pathway were induced after co-administration. Furthermore, cellular ROS increased after co-administration, and apoptosis was inhibited by the addition of ROS scavenger.ConclusionLBH589 combined with AM1241 activated the endoplasmic reticulum emergency pathway, DNA damage repair signaling pathway, oxidative stress and autophagy pathway, ultimately promoting the apoptosis of cervical cancer cells. These findings suggest that the co-administration of LBH589 and AM1241 may be a new treatment plan for the treatment of cervical cancer.

Transcription factor Dp-1 knockdown downregulates thymidine kinase 1 expression to protect against proliferation and epithelial-mesenchymal transition in cervical cancer.

Thymidine kinase 1 (TK1) level is an independent survival prognostic factor for both premalignant and malignant cervical pathologies. Herein, this study sought to probe the impacts of TK1 on cervical cancer (CC) progression and its underlying mechanism. Transcription factor Dp-1 (TFDP1) and TK1 expression was assessed using qRT-PCR in CC cell lines. After ectopic expression and knockdown experiments, cell counting kit-8 and colony formation assays were adopted to measure cell proliferation, western blot to examine the expression of epithelial-mesenchymal transition (EMT)-related proteins, and Transwell assays to assess cell invasion and migration. The binding of TFDP1 to TK1 was predicted by bioinformatic sites and verified by chromatin immunoprecipitation and dual-luciferase reporter assays. Tumor xenograft experiments in nude mice were performed to validate the influence of TFDP1/TK1 on CC progression in vivo. CC cells had high TK1 and TFDP1 expression. TFDP1 or TK1 knockdown restrained CC cell EMT, invasion, migration, and proliferation. TFDP1 facilitated TK1 expression in CC via transcription. Overexpression of TK1 counteracted the suppressive impacts of TFDP1 knockdown on CC cell malignant behaviors. Moreover, TFDP1 knockdown depressed CC growth in vivo by downregulating TK1. TFDP1 knockdown restricted proliferation and EMT in CC by downregulating TK1 expression.

MiR-17 ~ 92 suppresses proliferation and invasion of cervical cancer cells by inhibiting cell cycle regulator Cdt2

Cervical cancer (CC) is the 4th most leading cause of death among women worldwide, and if diagnosed in late stages the treatment options are almost negligible. 99% of CC is caused by high-risk human papilloma viruses (HR-HPV). Upon integration into human genome, the encoded viral proteins mis-regulate various onco-suppressors and checkpoint factors including cell cycle regulators. One such protein is cell cycle S phase licensing factor, CDC-10 dependent transcript-2 (Cdt2) which has been reported to be highly upregulated in various cancers including CC. Also, in CC cells, several tumor suppressor miRNAs are suppressed, including miR-17 ~ 92 cluster. In this study, we report that miR-17 ~ 92 directly recruits to 3’UTR of Cdt2 and downregulates this oncogene which suppresses the proliferation, migration and invasion capabilities of the CC cell lines without affecting non-cancerous cells. We further show that suppression of Cdt2 by miR-17 ~ 92, blocks the cancerous cells in S phase and induces apoptosis, eventually leading to their death. Hence, our work for the first time, mechanistically shows how miR-17 ~ 92 could work as tumor suppressor in cervical cancer cells, opening up the potential of miR-17 ~ 92 to be used in developing therapy for cervical cancer treatment.