Cervical Cancer Cell Lines CaSki Research Articles

Metformin induces apoptosis and inhibits migration by activating the AMPK/p53 axis and suppressing PI3K/AKT signaling in human cervical cancer cells.

Human cervical cancer is the fourth most common malignancy among women worldwide, and it is expected to result in 460,000 deaths per year by 2040. Moreover, patients with cervical cancer often display drug resistance and severe side effects; therefore, the development of effective novel chemotherapeutic agents is important. In the present study, the effects of metformin, a first-line therapeutic drug for type 2 diabetes mellitus, were evaluated in cervical cancer. Compared with the control group, metformin significantly inhibited cell viability and migration, and induced apoptosis and cell cycle arrest in human cervical cancer cell lines (CaSki and HeLa). Following metformin treatment, the protein expression levels of p-AMP-activated protein kinase (p-AMPK), which promotes cell death, and the tumor suppressor protein p-p53 were remarkably upregulated in CaSki and C33A cells compared with the control group. Furthermore, compared with the control group, metformin significantly suppressed the PI3K/AKT signaling pathway in CaSki, C33A and HeLa cells. Compound C (an AMPK inhibitor) significantly reversed the effects of metformin on CaSki, C33A and HeLa cell viability, and AMPK and p53 phosphorylation. The results of the present study suggested that metformin induced AMPK-mediated apoptosis, thus metformin may serve as a chemotherapeutic agent for human cervical cancer.

Trichostatin A Induces Autophagy in Cervical Cancer Cells by Regulating the PRMT5-STC1-TRPV6-JNK Pathway

Objective: The aim of this study was to investigate the effects of trichostatin A (TSA) on cervical cancer and the related mechanisms. Methods: The HeLa and Caski cervical cancer cell lines were treated with different concentrations of TSA. Cell viability was measured by MTT assays. Cell apoptosis was analysed using flow cytometry. Expression of transient receptor potential cation channel, subfamily V, member 6 (TRPV6), protein arginine methyltransferase 5 (PRMT5), and stanniocalcin 1 (STC1) was determined by qRT-PCR and Western blotting. Protein levels of LC3 II/I, beclin1, p62, JNK, and p-JNK were detected by Western blotting. Results: Treatment with TSA significantly decreased HeLa and Caski cell viability and enhanced the apoptosis rate in a dose-dependent manner. TSA markedly elevated beclin1 protein levels and the LC3 II/I ratio and significantly reduced p62 levels in a dose-dependent manner. In addition, TSA (1 μM) significantly suppressed PRMT5 and TRPV6 levels and enhanced STC1 and p-JNK levels. The lysosomal inhibitor bafilomycin-A1 synergistically enhanced the TSA-mediated increase in autophagic flux. Either the overexpression of TRPV6 or the inhibition of JNK signalling markedly enhanced cell viability, inhibited apoptosis, and autophagy and reduced p-JNK levels in TSA-treated cells. The inhibition of STC1 significantly increased TRPV6 protein levels and reduced p-JNK levels. Overexpression of PRMT5 dramatically decreased STC1 and p-JNK protein levels and increased TRPV6 levels. Conclusion: TSA suppresses cervical cancer cell proliferation and induces apoptosis and autophagy through regulation of the PRMT5/STC1/TRPV6/JNK axis.

Adipose-Derived Stem Cells Promote Proliferation and Invasion in Cervical Cancer by Targeting the HGF/c-MET Pathway.

BackgroundCervical cancer is a serious female malignancy affecting women’s health worldwide. The HGF/c-MET signaling pathway is activated in cervical cancer. Adipose-derived stem cells (ADSCs) with multipotential differentiation can carry out paracrine secretion of hepatocyte growth factor (HGF). Here, we investigated the effect and underlying mechanism of ADSCs on the promotion and invasion of cervical cancer in vitro and in vivo.Materials and MethodsADSCs were isolated, identified, and co-cultured with cervical cancer cells. HGF was detected using ELISA, and the HGF and c-MET signaling pathway was assessed with Western blot. The proliferation and invasion of human cervical cancer cell lines (HeLa and CaSki cells) were measured using CCK-8 and transwell assays. A HeLa xenograft mouse model was established to determine the effect of ADSCs on tumor growth in vivo.ResultsADSCs secreted a high level of HGF into the supernatant, while co-culture of ADSCs and cervical cancer cells increased the supernatant level of HGF. The HGF/c-MET pathway was activated in HeLa and CaSki cells co-cultured with ADSCs. Both co-culture with ADSCs and use of ADSC-derived conditioned medium (ADSCs-CM) significantly promoted the proliferation and invasion of cervical cancer cells in vitro, an effect that was reduced by inhibiting tumor cell c-MET expression. Furthermore, ADSCs-CM promoted HeLa cervical tumor growth in vivo, which could be suppressed by intratumoral c-MET siRNA injection.ConclusionADSCs promote cervical cancer growth and invasion through paracrine secretion of HGF and involvement of the HGF/c-MET signaling pathway.

Tripartite motif‑containing14 regulates cell proliferation and apoptosis in cervical cancer via the Akt signaling pathway.

Tripartite motif-containing (TRIM) 14 is a protein of the TRIM family. Studies have indicated that TRIM14 may be used as an oncogene in tumor cells, such as osteosarcoma, non-small cell lung cancer and breast cancer through different pathways. However, the functions of TRIM14 in cervical cancer cells remain unclear. Therefore, this study aimed to investigate the functions of TRIM14 in cervical cancer cells and its underlying mechanism. Caski cells stably expressing TRIM14 and SiHa, and HeLa cells stably expressing TRIM14 short hairpin RNA were constructed by lentivirus-mediated overexpression or knockdown systems. The effects of TRIM14 on proliferation and apoptosis of cervical cancer cells were detected by Cell Counting Kit-8 (CCK-8) assay and flow cytometry, respectively. In addition, reverse transcription-quantitative (RT-q) PCR and western blotting were used to investigate the expression levels of TRIM14 and of signaling pathway marker protein including P21, caspase-3, cleaved caspase-3, Akt and phosphorylated Akt. The results of RT-qPCR and western blotting revealed that TRIM14 was highly expressed in human cervical cancer tissues and cell lines compared with adjacent normal tissues and normal cervical epithelial cells. TRIM14 also regulated cell proliferation and apoptosis of human SiHa, HeLa and Caski cervical cancer cell lines through the Akt signaling pathway. Additionally, TRIM14 protein levels were related to the clinical and pathological features of cervical cancer. CCK-8 assay and flow cytometry demonstrated that TRIM14 expression could promote cervical cancer cell proliferation and autophagy suppression. Taken together, TRIM14-induced cell proliferation and apoptosis inhibition may by evoked by the activation of the Akt pathway. This study demonstrated the role of TRIM14 in cervical cancer, and reveals its mechanism of action as a potential therapeutic target for cervical cancer.

Rhopaladins' analogue (E)-2-aroyl-4-(4-fluorobenzylidene)-5-oxopyrrolidines inhibit proliferation, promote apoptosis and down-regulation of E6/E7 mRNA in cervical cancer

The occurrence and development of cervical cancer threaten women's life and health, HPV-induced cervical cancer is a major health issue among women. We synthesized three Rhopaladins' analogue (E)-2-aroyl-4-(4-fluorobenzylidene)-5-oxopyrrolidines via a tandem Ugi 4CC/SN cyclization with pyrrolidone as a core structure. In addition, the cytotoxicity of these new compounds in the cervical cancer cell line CaSki was studied by MTT assay. And then we chose one to research the apoptosis and the expression of E6/E7 mRNA in CaSki cells. The results indicated that the new compound can not only inhibited the proliferation of CaSki in dose-dependent and time-dependent manners but also induced the apoptosis, which may be related to the down-regulation of E6/E7 mRNA expression.

USP18 promotes cell proliferation and suppressed apoptosis in cervical cancer cells via activating AKT signaling pathway

BackgroundThe deubiquitinating (DUB) enzyme ubiquitin-specific protease 18 (USP18), also known as UBP43, is an ubiquitin-specific protease linked to several human malignancies. However, USP18’s underlying function in human cervical cancer remains unclear. In the current study, we aimed to analyse the role of USP18 and its signalling pathways in cervical cancer.MethodsQuantitative real-time polymerase chain reaction (qRT-PCR) and immunohistochemical staining were performed to analyse USP18 levels in cervical cancer and matched to adjacent normal tissues. Moreover, RNA interference (RNAi) and lentiviral-mediated vector transfections were performed to silence and overexpress USP18, respectively, in cervical cancer cells. Further, Cell Counting Kit-8 (CCK-8) and Annexin V/PI staining assays were used to assess its biological function in cell proliferation and apoptosis, respectively. A xenograft model was used to examine USP18’s function in vivo.ResultsThe present findings demonstrated that USP18 was overexpressed in cervical cancer specimens and cell lines. Silencing USP18 in SiHa and Caski cervical cancer cell lines inhibited cell proliferation, induced apoptosis, and promoted cleaved caspase-3 expression. In contrast, USP18 overexpression showed the opposite effects in human HcerEpic cells. A Gene Set Enrichment Analysis revealed that USP18 was enriched in the PI3K/AKT signalling pathway in cervical cancer. Hence, the PI3K/AKT inhibitor LY294002 was used to determine the relationship between USP18 and AKT in cervical cancer cells. Importantly, LY294002 significantly abolished the effects of USP18 overexpression in cervical cancer cells. In vivo, USP18 silencing inhibited human cervical cancer cells’ tumorigenicity.ConclusionsThe current study indicates that USP18 is an oncogenic gene in cervical cancer. Our findings not only deepened the understanding of USP18’s biological function in cervical cancer pathogenesis, but we also provided novel insight for cervical cancer therapy.Trial registrationRetrospectively registered.

Adenoviral Vectors Armed with PAPILLOMAVIRUs Oncogene Specific CRISPR/Cas9 Kill Human-Papillomavirus-Induced Cervical Cancer Cells.

Human papillomaviruses (HPV) cause malignant epithelial cancers including cervical carcinoma, non-melanoma skin and head and neck cancer. They drive tumor development through the expression of their oncoproteins E6 and E7. Designer nucleases were shown to be efficient to specifically destroy HPV16 and HPV18 oncogenes to induce cell cycle arrest and apoptosis. Here, we used high-capacity adenoviral vectors (HCAdVs) expressing the complete CRISPR/Cas9 machinery specific for HPV18-E6 or HPV16-E6. Cervical cancer cell lines SiHa and CaSki containing HPV16 and HeLa cells containing HPV18 genomes integrated into the cellular genome, as well as HPV-negative cancer cells were transduced with HPV-type-specific CRISPR-HCAdV. Upon adenoviral delivery, the expression of HPV-type-specific CRISPR/Cas9 resulted in decreased cell viability of HPV-positive cervical cancer cell lines, whereas HPV-negative cells were unaffected. Transduced cervical cancer cells showed increased apoptosis induction and decreased proliferation compared to untreated or HPV negative control cells. This suggests that HCAdV can serve as HPV-specific cancer gene therapeutic agents when armed with HPV-type-specific CRISPR/Cas9. Based on the versatility of the CRISPR/Cas9 system, we anticipate that our approach can contribute to personalized treatment options specific for the respective HPV type present in each individual tumor.

CRISPR-mediated knockdown of miR-214 modulates cell fate in response to anti-cancer drugs in HPV-negative and HPV-positive cervical cancer cells

Cervical cancer is the fourth most common cause of mortality in women worldwide. In this study we investigated the effect of a tumour suppressor microRNA miR-214 in modulating the cell death against chemotherapeutic drugs like Doxorubicin, Cisplatin and Paclitaxel. CRISPR-facilitated knockdown and plasmid-based overexpression of miR-214 was performed in cervical cancer cell lines HeLa, C33A and CaSki. It was observed that knocking out miR-214 resulted in reduced apoptosis and cell migration upon drug treatments; while overexpression of miR-214 resulted in marginal increase in apoptosis and cell migration when treated with drugs. However, miR-214 had very little effect on production of reactive oxygen species. Our results also indicate that Doxorubicin was least effective and Paclitaxel most effective in inducing cell death. A combination of miR-214 overexpression and Paclitaxel treatment was found to be most effective in inducing cell death in cervical cancer cells. Analysis of cell cycle phases followed by apoptotic markers also showed that miR-214 overexpression along with Paclitaxel treatment caused an increase in PARP and decline of PI-3 kinase/Akt levels. Therefore, miR-214 levels determine the fate of the cancer cell during chemotherapeutic treatment.

Evaluation of the anti-cervical cancer effect of a prodrug ：CBZ-AAN-DOX with hypoxic cell culture and tumor-bearing zebrafish models

BackgroundProdrugs are medications or compounds that, after administration, can be converted into pharmacologically active drugs through metabolism. Unlike conventional drugs, prodrugs have reduced adverse or unintended effects, which could become critical limitations in treatments such as chemotherapy. Previously through computer-aided drug design and chemical synthesis, we have obtained and examined a prodrug N-benzyloxycarbonyl-Ala-Asn-Doxorubicin (CBZ-AAN-DOX). CBZ-AAN-DOX is essentially Doxorubicin that is chemically-modified with tripeptides to target Legumain, a highly expressed protein in cancer cells and is involved in tumor metastasis and tumor microvessel formation. The difficulty to test the safety and efficacy of the prodrug (including the pharmacodynamic parameters of CBZ-AAN-DOX on metastasis and invasion of tumors, as well as cardiac and vascular toxicity) primarily comes from the lack of appropriate experimental models. MethodsHuman cervical cancer cell lines CaSki under hypoxic conditions were used to evaluate the cell viability by CCK-8 assay after the prodrug treatment. Western blotting method was performed for Legumain protein determination in the cell culture. Wound healing and transwell invasion assays were performed to determine the effects of the prodrug on tumor metastasis and invasion, respectively. Zebrafish models were constructed for toxicity and angiogenesis visual analysis after in vivo treatment with the prodrug. ResultsThe CCK-8 results showed that CBZ-AAN-DOX exhibits an IC50 of 28.7 μM in 48 h on CaSki cells that had a lower cell inhibition rate than DOX 80.3 μM for 24 h. Legumain expression was significantly increased in a time-dependent manner in 48 h under hypoxia conditions. The results also showed that 13.9 μM of the prodrug significantly inhibited the migration and invasion of cells and the effects were significantly stronger than that of 41.8 μM of DOX under hypoxia conditions after 48 h. The effects of 160 μM of the prodrug on the survival rate of zebrafish after 72 h and heart-toxicity showed no obvious abnormalities. Cell metastasis and angiogenesis were also inhibited in tumor-bearing zebrafish model. ConclusionThe findings in this study demonstrated that CBZ-AAN-DOX is a promising chemotherapy candidate with low toxicity and high efficiency for cervical cancer. Remarkably, the hypoxic culture model together with the zebrafish model serve as a good system for the evaluation of the toxicity, targeting and impact of the prodrug on tumor invasion and metastasis.

Eupatilin regulates proliferation and cell cycle of cervical cancer by regulating hedgehog signalling pathway

Eupatilin (5,7-dihydroxy-3',4',6-trimethoxyflavone) is a natural active substance found in génépi group plants, and its pharmacological activities has been proven to be useful in the treatment of various cancers. However, whether eupatilin demonstrates anti-cancer activity in cervical cancer is still under evaluation. To clarify this, cancer cell lines and nude mouse model were used in this study. The results indicated that eupatilin could inhibit the occurrence of cervical cancer both in vivo and in vitro. Cervical cancer cell lines (C4-1, HeLa, Caski, and Siha) and Ect1/E6E7 cells were incubated with eupatilin (40μM) for 48 hours. Compared with the control group, the viability of cervical cancer cells decreased significantly, while the apoptotic cells increased significantly. Cell cycle analysis showed that eupatilin treatment of HeLa and Caski cells reduced the proliferation index. Eupatilin at 40 mg/kg also inhibited tumour growth in tumour-bearing mice. Interestingly, weakened hedgehog signalling was observed in cervical cancer cells and tumours from tumour-bearing mice after eupatilin treatment. Our results reveal the inhibitory effect of eupatilin on cervical cancer and shed new light on the molecular mechanism of its therapeutic effect. SIGNIFICANCE OF THE STUDY: Eupatilin inhibited proliferation via promoting apoptosis and cell cycle arrest in HeLa and Caski cervical cancer cell lines. In addition, nude mouse tumourigenicity assay proved that eupatilin can suppress tumour growth in vivo. Dramatically, these activities might be involved in hedgehog signal pathway.

Clinical Significance of Ubiquitin-associated Protein 2-like in Patients With Uterine Cervical Cancer

Ubiquitin-associated protein 2-like (UBAP2L) has been demonstrated to be associated with the progression of multiple types of cancer. However, the function of UBAP2L in uterine cervical cancer remains unclear. Between 2005 and 2015, 84 patients who underwent surgery were included in this study. The patients were stratified into two groups on the basis of immunohistochemical staining for UBAP2L, and survival analysis was performed. Moreover, loss-of-function analysis was performed using the cervical cancer cell lines CaSki and SiHa. Based on immunohistochemistry, the overall survival in patients with low UBAP2L expression was significantly longer than that of those with high UBAP2L expression (p=0.045). The in vitro experiment revealed that knockdown of UBAP2L remarkably inhibited cell proliferation in both live cell imaging and the MTS assay. Patients with high UBAP2L expression had unfavorable prognosis and UBAP2L appears to play an important role in proliferation.

MiR-9-5p Exerts a Dual Role in Cervical Cancer and Targets Transcription Factor TWIST1.

Squamous cell carcinoma (SCC) and adenocarcinoma (AC) represent the major cervical cancer histotypes. Both histotypes are caused by infection with high-risk HPV (hrHPV) and are associated with deregulated microRNA expression. Histotype-dependent expression has been observed for miR-9-5p, showing increased expression in SCC and low expression in AC. Here, we studied the regulation and functionality of miR-9-5p in cervical SCCs and ACs using cervical tissue samples and hrHPV-containing cell lines. Expression and methylation analysis of cervical tissues revealed that low levels of miR-9-5p in ACs are linked to methylation of its precursor genes, particularly miR-9-1. Stratification of tissue samples and hrHPV-containing cell lines suggested that miR-9-5p depends on both histotype and hrHPV type, with higher expression in SCCs and HPV16-positive cells. MiR-9-5p promoted cell viability and anchorage independence in cervical cancer cell lines SiHa (SCC, HPV16) and CaSki (metastasized SCC, HPV16), while it played a tumor suppressive role in HeLa (AC, HPV18). TWIST1, a transcription factor involved in epithelial-to-mesenchymal transition (EMT), was established as a novel miR-9-5p target. Our results show that miR-9-5p plays a dual role in cervical cancer in a histotype- and hrHPV type-dependent manner. MiR-9-5p mediated silencing of TWIST1 suggests two distinct mechanisms towards EMT in cervical cancer.

SMYD2 promotes cervical cancer growth by stimulating cell proliferation

BackgroundCervical cancer is the most common gynecological malignancy with low terminal cure rate, and therefore new therapeutic targets are urgently needed to combat this disease. SMYD2, as an oncogene, is abnormal highly expressed in multiple types of tumors and further affects the occurrence and development, but the potential correlations between SMYD2 expression and cervical cancer progression is still unclear.MethodsWe first used the bioinformatics website to screen the data of cervical cancer in (The Cancer Genome Atlas) TCGA and survival analysis was used to find the different survival rates in the SMYD2 high expression group and low expression group. Through immunohistochemistry, the association between SMYD2 expression and clinical-pathological features of cervical cancer patients was further evaluated. Quantitative PCR and Immunoblot were applied to investigate the relative mRNA and protein expression levels, respectively. In vivo and in vitro experiments were performed to explore the function of SMYD2 in cancer progression.ResultsWe first found a high expression of SMYD2 in cervical cancer, and survival analysis found that the poorer survival rate in the SMYD2 high expression group than that in the low expression group. Herein, our study demonstrated that the expression of SMYD2 in patients with cervical cancer was associated with FIGO stage, tumor size and further correlated with poor prognosis. Our data further showed that the inhibition of SMYD2 expression in cervical cancer cell line Caski and Siha could dramatically block the proliferation of cervical cancer cells. Additionally, SMYD2-shRNA lentivirus infected remarkably inhibited tumorigenesis in mice compared with the scramble group.ConclusionsTaken together, this study provides strong evidence of the involvement of SMYD2 in cervical cancer growth and indicates that it could have high potential as a therapeutic target of cervical cancer.

Human papillomavirus 16E6/E7 activates autophagy via Atg9B and LAMP1 in cervical cancer cells.

BackgroundsAlthough the role of high‐risk human papillomavirus (HPV) E6 and E7 in cellular malignant transformation has been elucidated， the function of both genes in cellular homeostasis is still unknown. Autophagy functions in maintenance of cellular homeostasis play a key role in the initiation and development of cancer and infectious disease.MethodsCervical cancer cell lines SiHa and CaSki were utilized in this study.ResultsWe found that HPV 16E6/E7 (16E6/E7) downregulation inhibited autophagy, and consequently suppressed cell proliferation and promoted early apoptosis. Transcriptome sequencing demonstrated that Atg9B and LAMP1 were downregulated in 16E6/E7 knockdown cells. Gene function experiments revealed that 16E6/E7 downregulation depressed Atg9B and LAMP1, and Atg9B and LAMP1 overexpression compensated, at least partially, autophagy blockage induced by 16E6/E7 knockdown. Immunoprecipitation assay showed that 16E7 interacted with Atg9B and dual‐luciferase reporter system revealed that 16E6 most likely regulated −1750 to −2000 nt in Atg9B and −1800 to −2000 nt in LAMP1 promoter region.ConclusionsOur findings verified that 16E6/E7 activated autophagy via accelerating autophagosome formation and degradation, and Atg9B and LAMP1 were involved in the process of 16E6/E7 modulating autophagy, suggesting that targeting autophagy may be a potential approach in cervical cancer therapeutics.

HPV transcription in skin tumors.

BackgroundAlthough more than 95% of viral sequences found in skin tumors typically belong to human papillomaviruses (HPVs), HPV transcription has so far not been detected. As current technology allows very deep transcriptome sequencing, we examined skin tumors and precursor lesions for HPV transcription.MethodFresh frozen biopsies from 12 skin specimens (11/12 were positive for HPV DNA) were subjected to total RNA sequencing. The cervical cancer cell line CaSki was included as a positive control for HPV transcription.ResultsHPV RNA was detected and confirmed in 1/12 skin lesions at a median depth of 66 million reads per sample. One specimen was positive for HPV 110 transcripts mapping to E6, E7, E2/E4 and L2 open reading frames, as well as to a spliced E1^E4 transcript.ConclusionIn conclusion, the study revealed that a minority of skin lesions contains HPV transcripts and that HPV DNA detection does not predict HPV transcriptional activity.

CKD-602, a topoisomerase I inhibitor, induces apoptosis and cell-cycle arrest and inhibits invasion in cervical cancer

BackgroundCervical cancer is the third most common gynecological malignancy. Conventional treatment options are known to be ineffective for the majority of patients with advanced or recurrent cervical cancer. Therefore, novel therapeutic agents for cervical cancer are necessary. In this study, the effects of CKD-602 in cervical cancer were investigated.MethodsThree established human, immortalized, cervical cancer cell lines (CaSki, HeLa and SiHa) were used in this study. Following treatment with CKD-602, apoptosis was quantified using fluorescein isothiocyanate Annexin V-FITC and propidium iodide (PI) detection kit and cell cycle analysis was analyzed using fluorescence activated cell sorting (FACS). Transwell chambers were used for invasion assays. Western blot assay was performed to analyze proteomics. CaSki cells were subcutaneously injected into BALB/c-nude mice and cervical cancer xenograft model was established to elucidate the antitumor effect of CKD-602 in vivo.ResultsTreatment with CKD-602 induced apoptosis and increased expression of the enzyme PARP, cleaved PARP, and BAX. In addition, expression of phosphorylated p53 increased. Cell cycle arrest at G2/M phase and inhibition of invasion were detected after treatment with CKD-602. A significant decrease in cervical cancer tumor volume was observed in this in vivo model, following treatment with CKD-602.ConclusionsThis is the first report of CKD-602 having an antitumor effect in cervical cancer in both an in vitro and in vivo models. The results of this study indicate that CKD-602 may be a novel potential drug, targeting cervical cancer, providing new opportunities in the development of new therapeutic strategies.

Up-regulation of miRNA-148a inhibits proliferation, invasion, and migration while promoting apoptosis of cervical cancer cells by down-regulating RRS1.

The purpose of the present study is to figure out the role of miRNA-148a (miR-148a) in growth, apoptosis, invasion, and migration of cervical cancer cells by binding to regulator of ribosome synthesis 1 (RRS1). Cervical cancer and adjacent normal tissues, as well as cervical cancer cell line Caski, HeLa, C-33A, and normal cervical epithelial cell line H8 were obtained to detect the expression of miR-148a and RRS1. Relationship between miR-148a and RRS1 expression with clinicopathological characteristics was assessed. The selected Caski and HeLa cells were then transfected with miR-148a mimics, miR-148a inhibitors or RRS1 siRNA to investigate the role of miR-148a and RRS1 on proliferation, apoptosis, colony formation, invasion, and migration abilities of cervical cancer cells. Bioinformatics information and dual luciferase reporter gene assay was for used to detect the targetting relationship between miR-148a and RRS1. Down-regulated miR-148a and up-regulated RRS1 were found in cervical cancer tissues and cells. Down-regulated miR-148a and up-regulated RRS1 are closely related with prognostic factors of cervical cancer. RRS1 was determined as a target gene of miR-148a and miR-148a inhibited RRS1 expression in cervical cancer cells. Up-regulation of miR-148a inhibited cell proliferation, migration, and invasion while promoting apoptosis in Caski and HeLa cells. Our study suggests that miR-148a down-regulates RRS1 expression, thereby inhibiting the proliferation, migration, and invasion while promoting cell apoptosis of cervical cancer cells.

Cervical Cancer Correlates with the Differential Expression of Nicotinic Acetylcholine Receptors and Reveals Therapeutic Targets.

Nicotinic acetylcholine receptors (nAChRs) are associated with various cancers, but the relation between nAChRs and cervical cancer remains unclear. Therefore, this study investigated the differential expression of nAChR subunits in human cervical cancer cell lines (SiHa, HeLa, and CaSki) and in normal ectocervical cell lines (Ect1/E6E7) at mRNA and protein levels. Two specific nAChR subtype blockers, αO-conotoxin GeXIVA and α-conotoxin TxID, were then selected to treat different human cervical cancer cell lines with specific nAChR subtype overexpression. The results showed that α3, α9, α10, and β4 nAChR subunits were overexpressed in SiHa cells compared with that in normal cells. α9 and α10 nAChR subunits were overexpressed in CaSki cells. α*-conotoxins that targeted either α9α10 or α3β4 nAChR were able to significantly inhibit cervical cancer cell proliferation. These findings may provide a basis for new targets for cervical cancer targeted therapy.

Human Papillomavirus E6/E7 and Long Noncoding RNA TMPOP2 Mutually Upregulated Gene Expression in Cervical Cancer Cells.

TMPOP2 was previously suggested to be an oncogenic long noncoding RNA which is excessively expressed in cervical cancer cells and inhibits E-cadherin gene expression by recruiting transcription repressor EZH2 to the gene promoter. So far, the function and regulation of TMPOP2 in cervical cancer remain largely unknown. Herein, we found that TMPOP2 expression was correlated with human papillomavirus 16/18 (HPV16/18) E6 and E7 in cervical cancer cell lines CaSki and HeLa. Tumor suppressor p53, which is targeted for degradation by HPV16/18, was demonstrated to associate with two p53 response elements in the TMPOP2 promoter to repress the transcription of the TMPOP2 gene. Reciprocally, ectopic expression of TMPOP2 was demonstrated to sequester tumor repressor microRNAs (miRNAs) miR-375 and miR-139 which target HPV16/18 E6/E7 mRNA and resulted in an upregulation of HPV16/18 E6/E7 genes. Thereby, HPV16/18 E6/E7 and the long noncoding RNA (lncRNA) TMPOP2 form a positive feedback loop to mutually derepress gene expression in cervical cancer cells. Moreover, results of RNA sequencing and cell cycle analysis showed that knockdown of TMPOP2 impaired the expression of cell cycle genes, induced cell cycle arrest, and inhibited HeLa cell proliferation. Together, our results indicate that TMPOP2 and HPV16/18 E6/E7 mutually strengthen their expression in cervical cancer cells to enhance tumorigenic activities.IMPORTANCE Human papillomaviruses 16 and 18 (HPV16/18) are the main causative agents of cervical cancer. Viral proteins HPV16/18 E6 and E7 are constitutively expressed in cancer cells to maintain oncogenic phenotypes. Accumulating evidences suggest that HPVs are correlated with the deregulation of long noncoding RNAs (lncRNAs) in cervical cancer, although the mechanism was unexplored in most cases. TMPOP2 is a newly identified lncRNA excessively expressed in cervical cancer. However, the mechanism for the upregulation of TMPOP2 in cervical cancer cells remains largely unknown and its relationship with HPVs is still elusive. The significance of our research is in revealing the mutual upregulation of HPV16/18 E6/E7 and TMPOP2 with the molecular mechanisms explored. This study will expand our understandings of the oncogenic activities of human papillomaviruses and lncRNAs.

Biological activities of Ficus carica latex for potential therapeutics in Human Papillomavirus (HPV) related cervical cancers

Infection caused by high-risk human papillomaviruses (HPVs) are implicated in the aetiology of cervical cancer. Although current methods of treatment for cervical cancer can ablate lesions, preventing metastatic disseminations and excessive tissue injuries still remains a major concern. Hence, development of a safer and more efficient treatment modality is of vital importance. Natural products from plants are one of the principal sources of precursors to lead compounds with direct pharmaceutical application across all disease classes. One of these plants is Ficus carica, whose fruit latex, when applied on HPV-induced skin warts, has shown potential as a possible cure for this virus related lesions. This study explores the in vitro biological activities of fig latex and elucidates its possible mechanisms of action on cervical cancer cell lines CaSki and HeLa positive for HPV type 16 and 18, respectively. Our data shows that fig latex inhibits properties that are associated with HPV-positive cervical cancer transformed cells such as rapid growth and invasion and substantially downregulated the expression of p16 and HPV onco-proteins E6, E7. These findings suggest Ficus carica latex has the potential to be used in the development of therapeutic modalities for the possible treatment, cure and prevention of HPV related cervical cancer.