Uterine Cervical Cancer Cell Lines Research Articles

Fyn expression is associated with the response of patients with locally advanced uterine cervical squamous cell carcinoma to neoadjuvant chemotherapy.

Neoadjuvant chemotherapy (NAC) followed by surgery is the current standard of treatment for locally advanced uterine cervical cancer; however, its value and outcomes remain contested. Identifying biomarkers that allow for the prediction of the effect of NAC efficacy before initiation of treatment is essential, in order to assist in choosing the optimum therapeutic regimen to maximize the beneficial outcomes of treatment. In the present retrospective study, 44 patients with locally advanced uterine cervical squamous cell carcinoma who underwent NAC were divided into two groups: A NAC successful group and a NAC failure group, depending on the efficacy of NAC. Subsequently, the association between Fyn expression, a non-receptor tyrosine kinase that is a member of the Src family kinases, and NAC efficacy was determined; Fyn expression was detected by immunohistochemistry and assessed using a weighted scoring method. Additionally, the effect of Fyn knockdown on the sensitivity of a uterine cervical cancer cell line to cisplatin was determined. Notably, there were no significant differences between the two groups of patients regarding their characteristics. Regarding overall survival, the NAC successful group had a significantly longer survival time than the NAC failure group (P=0.01). Furthermore, the expression levels of Fyn in tumor tissues were significantly lower in the NAC successful group compared with those in the NAC failure group (P=0.003). The patients were subsequently divided into two groups (high expression group and low expression group) according to a cutoff value of 3, which was determined by producing a receiver operating characteristic curve from the weighted scores. The low expression group was significantly more sensitive to NAC than the high expression group (P<0.001). In vitro experiments revealed that Fyn knockdown significantly enhanced the sensitivity of uterine cancer cells to cisplatin (P<0.05). In conclusion, Fyn expression may be a potentially useful biomarker for predicting the response to NAC in patients with locally advanced uterine cervical squamous cell carcinoma, and may also be a promising molecular target for the management of uterine cancer.

Silencing of Fused Toes Homolog (FTS) Increases Radiosensitivity to Carbon-Ion Through Downregulation of Notch Signaling in Cervical Cancer Cells.

The effects of Carbon ion radiation (C-ion) alone or in combination with fused toes homolog (FTS) silencing on Notch signaling were investigated in uterine cervical cancer cell lines (ME180 and CaSki). In both cell lines, upon irradiation with C-ion, the expression of Notch signaling molecules (Notch1, 2, 3 and cleaved Notch1), γ-secretase complex molecules and FTS was upregulated dose-dependently (1, 2 and 4 Gy) except Notch1 in ME180 cells where the change in expression was not significant. However, overexpression of these molecules was attenuated upon silencing of FTS. The spheroid formation, expression of stem cell markers (OCT4A, Sox2 and Nanog) and clonogenic cell survival were reduced by the combination as compared to FTS silencing or C-ion irradiation alone. Additionally, immunoprecipitation and immunofluorescence assay revealed interaction and co-localization of FTS with Notch signaling molecules. In conclusion, FTS silencing enhances the radio-sensitivity of the cervical cancer cells to C-ion by downregulating Notch signaling molecules and decreasing the survival of cancer stem cells.

MicroRNA-101 Promotes the Proliferation, Migration, and Invasion of Uterine Cervix Cancer Cells by Targeting Cyclin-Dependent Kinase 8

Uterine cervical cancer (UCC), or carcinoma of the uterine cervix, is a familiar malignancy in gynecology. The expression of multiple microRNAs is abnormal in UCC. Research has demonstrated that the level of microRNA-101 (miR-101) was decreased in UCC, but the mechanism by which miR-101 regulates UCC is still unclear. The TargetScan software predicted that one of the target genes of miR-101 was CDK8. This study aims to explore whether miR-101 affects the migration, invasion, and proliferation of UCC cells through CDK8. First, nanoparticle-assisted PCR was used to determine the levels of miR-101 and CDK8 in UCC tissues, normal adjacent tissues, and two UCC cell lines, C-33A and Siha. Compared to the normal tissues, the level of miR-101 was decreased in UCC tissues, while the level of CDK8 was increased. The dual-luciferase reporter experiments confirmed that miR-101 directly interacted with the binding site in CDK8 3’UTR to regulate luciferase activity. The UCC cells were transfected with the MIR101 mimic construct to overexpress miR-101. It was demonstrated that cell migration, invasion, and proliferation was reduced in C-33A cells overexpressing miR-101. In the cells co-transfected with CDK8 and MIR101, the overexpression of CDK8 reversed the effect of MIR101 overexpression on cell migration, invasion, and proliferation. Therefore, miR-101 can regulate the migration, invasion, and proliferation of UCC cells by targeting CDK8. Therefore, miR-101 has potential applications in the treatment of UCC.

Regio-specific biotransformation of alizarin to alizarin methoxide with enhanced cytotoxicity against proliferative cells.

Alizarin has been reported to have an antigenotoxic activity along with an inhibitory effect on the tumor cell growth of human colon carcinoma cells. Alizarin was biotransformed into an O-methoxide derivative using O-methyltransferase from Streptomyces avermitilis MA4680 (SaOMT2) to enhance its bioefficacy. The biotransformed product was extracted, purified, and characterized using various chromatographic and spectroscopic analyses, and confirmed to be an alizarin 2-O-methoxide. The antiproliferative activity of the compound against gastric cancer cells (AGS), uterine cervical cancer (Hela), liver cancer (HepG2), and normal cell lines was investigated. Alizarin 2-O-methoxide showed an inhibitory effect on all three cancer-cell lines at very low concentrations, from 0.078µM, with no cytotoxicity against 267B1 (human prostate epithelial) and MRC-5 (normal human fetal lung fibroblast).

CXCL3 overexpression promotes the tumorigenic potential of uterine cervical cancer cells via the MAPK/ERK pathway.

CXCL3 belongs to the CXC-type chemokine family and is known to play a multifaceted role in various human malignancies. While its clinical significance and mechanisms of action in uterine cervical cancer (UCC) remain unclear. This investigation demonstrated that the UCC cell line HeLa expressed CXCL3, and strong expression of CXCL3 was detected in UCC tissues relative to nontumor tissues. In addition, CXCL3 expression was strongly correlated with CXCL5 expression in UCC tissues. In vitro, HeLa cells overexpressing CXCL3, HeLa cells treated with exogenous CXCL3 or treated with conditioned medium from WPMY cells overexpressing CXCL3, exhibited enhanced proliferation and migration activities. In agreement with these findings, CXCL3 overexpression was also associated with the generation of HeLa cell tumor xenografts in athymic nude mice. Subsequent mechanistic studies demonstrated that CXCL3 overexpressing influenced the expression of extracellular signal-regulated kinase (ERK) signaling pathway associated genes, including ERK1/2, Bcl-2, and Bax, whereas the CXCL3-induced proliferation and migration effects were attenuated by exogenous administration of the ERK1/2 blocker PD98059. The data of the current investigation support that CXCL3 appears to hold promise as a potential tumor marker and interference target for UCC.

DNA binding interaction studies of flavonoid complexes of Cu(II) and Fe(II) and determination of their chemotherapeutic potential

The present study is based on molecular level investigation of DNA binding of three flavonoids (Fls), morin (mor), quercetin (quer) and primuletin (prim) and their metal (Cu (II) and Fe (III)) complexes through UV–Vis spectroscopy, fluorescence spectroscopy, thermal analysis and cyclic voltammetry (CV). The spectroscopic experiments were performed by titrating compounds with DNA and the results were in good agreement with those obtained from titration of DNA by the compounds. The Fe-mor, Cu-quer, Fe-quer and prim which exhibited hypsochromic/hyperchromic shifts in UV–Vis spectra, showed negligible effects over florescent spectra of NR-DNA (intercalating Neil red dye–DNA complex), intact Tm (thermal melting temperature) of DNA and the shift of peak potential (Ep) towards less positive value were designated to exhibit electrostatic mode of binding with dsDNA having binding constant, Kb ≈ 102 M−1. The mor, Cu-mor, Cu-prim and Fe-prim showed intercalating mode of interaction with dsDNA which was recognized from hypochromic/bathochromic shifts in the spectra, Ep shifts towards higher potential in CV, significant decay in fluorescence intensity, distinct shift in Tm of DNA and binding constant (Kb) of the order of 104 M−1. The mor exhibited mixed binding mode (intercalation and groove binding) at different concentrations. The quer displayed increase in peak current and hyperchromism thus depicted groove binding into dsDNA (Kb ≈ 103 M−1). The binding modes were found to be correlated with the apoptotic activity of the Fls and M-Fls (flavonoids and metal-flavonoids) assayed against human breast cancer cell lines (MCF-7) and human uterine cervical cancer cell lines (HeLa). The correlation is interpreted in terms of, the intercalation mode as cytostatic activity and the groove binding with no apoptosis. However, electrostatic binding of (M-)Fls to dsDNA did not produce significant anti-proliferation activity against Hela cell lines with exception of Fe-mor (cytostatic activity) and Cu-quer (cytotoxicity) against MCF-7 cell line.

Abstract 529: The significance of activated PI3K/AKT pathway in FGFR3-TACC3 fusion positive cervical cancer

Abstract Uterine cervical cancer is one of the most common cancer in women worldwide, and the prognosis in advanced or recurrent cases remains poor because of no effective molecular target therapies for this disease. The aim of our study is to identify and validate therapeutically targetable gene fusions in uterine cervical cancer, leading to the development of new therapeutic strategies. We have analyzed RNA sequencing data of 253 TCGA cervical cancer samples to search for gene fusions by using PRADA algorithm, and validated recurrent fusions in our Japanese dataset (n = 100) by RT-PCR and sanger sequencing. In TCGA samples, we detected 358 fusion transcripts and extracted 3 kinds of recurrent in-frame fusion transcripts (FGFR3-TACC3, ARL8B-ITPR1 and NXN-ABR). We focused on FGFR3-TACC3 fusion as a candidate of therapeutic kinase fusion and identified FGFR3-TACC3 fusion in 2 of 253 (0.8%) TCGA samples and 2 of 100 (2%) Japanese samples. All of fusion positive samples, which were histologically diagnosed as squamous cell carcinoma, showed high expression of both FGFR3 and TACC3 genes. To evaluate the possibility as therapeutically targetable fusions in uterine cervical cancer, we transfected FGFR3-TACC3, wild type FGFR3 and TACC3 transcripts to normal immortalized cervical keratinocytes derived from ectocervix (Ect1/E6E7) and four uterine cervical cancer cell lines (SiHa, ME180, HeLa, CaSki). Continuous expression of FGFR3-TACC3 fusion transcript led to anchorage-independent growth in Ect1/E6E7 and the dramatically alteration of cell proliferation in all cancer cell lines. On the other hand, no obvious phenotype change was observed in FGFR3 or TACC3 transfected cells. Western blotting analysis demonstrated that MAPK pathway was activated in all the fusion transfected cell lines but PI3K/AKT pathway was activated only in ME180 and CaSki harboring PIK3CA mutation. Fusion transfected cell lines exhibited high sensitivity to fusion specific siRNA and FGFR inhibitor compared to control. Although PI3K/AKT activated cell lines (ME180 and CaSki) showed less effective against FGFR inhibitor compared to PI3K/AKT neutral cell lines (SiHa and HeLa), combined inhibition of FGFR and AKT had a synergic effect in PI3K/AKT activated cell lines. Our findings suggest FGFR3-TACC3 fusion gene is an oncogenic driver event and therapeutic target in a fraction of cervical cancer. When FGFR3-TACC3 fusion positive cervical cancer is treated by FGFR inhibitor, genomic background such as PI3K/AKT status should be considered. Citation Format: Ryo Tamura, Kosuke Yoshihara, Tetsuya Saito, Ryosuke Ishimura, Emmanuel Martínez-Ledesma, Yutaro Mori, Kaoru Yamawaki, Kazuaki Suda, Tatsuya Ishiguro, Yoichi Aoki, Seiya Sato, Hiroaki Itamochi, Masaaki Komatsu, Roeland Verhaak, Takayuki Enomoto. The significance of activated PI3K/AKT pathway in FGFR3-TACC3 fusion positive cervical cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 529. doi:10.1158/1538-7445.AM2017-529

Abstract 1168: The codon 389 polymorphism of PICT-1 is a risk factor for human cervical cancer

Abstract The uterine cervical cancers profoundly involve in the infection with human papillomavirus (HPV), and cause the deaths of more than 250,000 women all over the world. To date, the carcinogenesis of uterine cervical cancers was not fully understood, then we have to investigate more precise genetic and molecular events to develop early diagnosis and identify new therapeutic targets. The PICT-1 (Protein Interacting with Carboxyl Terminus-1), one of the nucleolar proteins, has tumor suppressor functions, but its association with uterine cervical carcinogenesis has been unknown. So we investigate PICT-1 gene mutations, polymorphism on codon 389 (rs184994), and protein expression levels to investigate the association with pathogenesis of uterine cervical cancers. Firstly we found missense mutations of functionally important regions of PICT-1 in one of seven uterine cervical cancer cell lines (14%) and one of 10 surgical samples (10%). Next we focused on codon 389 polymorphism (Gln to Arg) which located in important regions of PICT-1 function. In result there was a statistically significant association between PICT-1 codon 389 polymorphism and the risk of uterine cervical cancers: A/G (odds ratio 6.48, 95% confidence interval 1.98-21.22, P = 0.0012), G/G (odds ratio 3.15, 95% confidence interval 1.03-9.61, P = 0.0403), and A/G or G/G (odds ratio 4.44, 95% confidence interval 1.62-12.23, P = 0.0026). We also identified PICT-1 protein level was reduced in uterine cervical cancer cell lines by Western blotting and cervical cancer tissues by immunohistochemistry staining (IHC). In IHC analysis, expression of PICT-1 in adjacent normal cervix was found in nucleus, especially nucleolus, but in differentiating cells layers located upper parabasal cell layer, PICT-1 also expressed in cytoplasm and gradually reduced the expression of nucleolus. In patient tissues, compared to normal epithelium, we found reduction of PICT-1 expression in most samples found even in uterine cervical cancers at early invasive lesions, and weaker PICT-1 expression was observed in more invasive lesions. Interestingly, we also detected high expressed and/or re-expressed PICT-1 in cytoplasm and/or nucleolus of keratinized lesions of cervical cancers. Our results indicate that disruption of PICT-1 by gene mutation and/or reduction of protein level may associate with the pathogenesis of uterine cervical cancers, and its codon 389 polymorphism may increase the risk of uterine cervical cancers. And also we suggested that PICT-1 located in cytoplasm may be important to squamous cell differentiation, and we speculated the further study of association between PICT-1 and cell differentiation would be of value to the field of the differentiation-inducing therapy for many hard-to-treat patients of many cancers, including uterine cervical cancers. Citation Format: Masafumi Yoshimoto, Aoi Tokuda, Shoko Takahashi, Yuji Yaginuma. The codon 389 polymorphism of PICT-1 is a risk factor for human cervical cancer. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 1168.

Cordycepin increases radiosensitivity in cervical cancer cells by overriding or prolonging radiation-induced G2/M arrest

Cordycepin (3-deoxyadenosine) has many pharmacological activities. We studied the radiosensitising effect of cordycepin and the underlying mechanisms relating to cell cycle changes in two human uterine cervical cancer cell lines, ME180 and HeLa cells. Cordycepin produced concentration- and time-dependent reductions in cell viability with more pronounced effects in ME180 cells. Cells pre-treated with cordycepin showed lower cell survival than those exposed to irradiation only. Radiation-induced expression of the histone, γ-H2AX, and apoptosis were also increased following cordycepin pre-treatment. In ME180 cells, pre-treatment with cordycepin reduced radiation-induced G2/M arrest and this G2/M checkpoint override was sustained for longer than in HeLa cells, where G2/M arrest was observed earlier and more briefly, the number of HeLa cells in the G2/M phase was subsequently increased. Cordycepin produced different effects on the expression of p53 and cell cycle checkpoint proteins in these two cell lines. It can be assumed that the mechanism underlying cordycepin-mediated radiosensitisation involves multiple effects that are primarily based on the induction of p53-mediated apoptosis and modulation of the expression of cell cycle checkpoint molecules.

CD24 expression as a marker for predicting clinical outcome and invasive activity in uterine cervical cancer.

CD24, a small heavily glycosylated mucin-like glycosylphosphatidylinositol-anchored cell surface protein, plays an important role in the carcinogenesis of various human malignancies. However, its function in cervical cancer remains unclear. The aim of the present study was to evaluate the expression of CD24 clinicopathologically and to analyze its functional behavior biologically in cervical cancer. A total of 117 uterine cervical cancer tumors were immunohistochemically analyzed using a CD24 monoclonal antibody on paraffin blocks. We also examined whether CD24 enhanced the invasive activity or the Akt, ERK, NF-κB and MMP activity in a uterine cervical cancer cell line (CaSki) by a western blot analysis. The patients with enhanced CD24 expression had a higher rate of advanced clinical stage (50 vs. 16.5%, p<0.01), lymph node metastasis (34.6 vs. 14.3%) and lymphovascular involvement (65.4 vs. 20.4%, p=0.01), and a poor overall and disease-free survival (5-year survival rate: 62 vs. 86%, p=0.03). CD24 overexpression in CaSki cells resulted in activation of Cell Signaling proteins, including Akt, ERK, NF-κB and MMP-9. An invasion assay showed that CD24 overexpression in CaSki cells led to increased invasion ability. The CD24 overexpression also increased mRNA expression of Slug but not Snail. Moreover, the CD24 overexpression also decreased expression of E-cadherin and increased N-cadherin protein levels. Increased expression of CD24 may be associated with tumor progression and prognosis in patients with uterine cervical cancer. CD24 expression may therefore be used not only as a prognostic marker in uterine cervical cancer, but also as a target for the development of new therapeutic approaches.

Sequential effects of the proteasome inhibitor bortezomib and chemotherapeutic agents in uterine cervical cancer cell lines

Although the prognosis of uterine cervical cancer has improved due to the advances of treatment modalities, survival of recurrent or metastatic cervical cancer remains poor. Cisplatin is an effective radiosensitizer, but its single agent activity in recurrent cervical cancer is disappointing. Inactivation of tumor suppressors through ubiquitin-mediated degradation by human papillomavirus is known to be a critical step in the carcinogenesis of uterine cervix. Bortezomib, a selective inhibitor of the proteasome, has been shown to inhibit the growth of several solid tumors. To determine the role of bortezomib in cervical cancer as a chemotherapeutic agent, we studied its biological properties. Bortezomib efficiently inhibited the proteasomal activities in cervical cancer cells, and an increased expression of tumor suppressors such as p53, hDlg and hScrib became evident. In addition, sequential or concomitant treatment of bortezomib and cisplatin stimulated the expression of p53, hScrib and p21 and the stimulation was markedly influenced by the order of drugs in HeLa cells. We further confirmed that the concomitant use of bortezomib and cisplatin has synergistic inhibitory effects on the growth of xenograft tumors derived from HeLa cells. Our data establish the possibility that the concomitant use of bortezomib and cisplatin could be an alternative choice in cases resistant to conventional chemotherapy, and sequential effects must be considered for advanced and therapy-resistant cervical cancer patients.

The activity of G-ROS and the predominant role of Type II reaction in the photodynamic therapy using 9-hydroxypheophorbide-α for HeLa cell lines

Photodynamic therapy (PDT) is a treatment modality that destroys the tumor. It activates the photosensitizer with the light of a specific wavelength, where the light is well absorbed by the photosensitizer, thus causing a fatal injury and thereby leading to a tumor necrosis. To date, a hematoporphyrin-derived photosensitizer has been widely used. It is disadvantageous, however, in that it causes a long-term photo-toxicity and has a poor selectivity for the tumor. This had led to the development of a chlorophyll-derived photosensitizer. We conducted this study to elucidate the mechanisms by which the activity of ROS is involved in the PDT using a novel type of chlorophyll-derived photosensitizer, 9-hydroxypheophorbide-α (9-HpbD-α), for the HeLa cell lines. Besides, we also attempted to determine which reaction plays a predominant role in the synthesis of ROS, either Type I reaction or Type II one, when both reactions are involved in the synthesis of ROS during the PDT using 9-HpbD-α. Our results showed not only that the activity of ROS is involved in the PDT using 9-HpbD-α in human uterine cervical cancer cell lines but also that the mechanisms of PDT are based on Type II reaction where the singlet oxygen is involved.

CombinedE7-Dendritic Cell-Based Immunotherapy and Human Sodium/Iodide Symporter Radioiodine Gene Therapy with Monitoring of Antitumor Effects by Bioluminescent Imaging in a Mouse Model of Uterine Cervical Cancer

Using a uterine cervical cancer cell line expressing human papillomavirus (HPV) 16 E7 antigen and bioluminescent imaging (BLI), we evaluated the therapeutic potential of combined immunotherapy using transfected dendritic cells (DC-E7) and human sodium/iodide symporter (hNIS) radioiodine gene therapy in a xenograft animal cancer model. Dendritic cells expressing either E7 antigen (DC-E7) or no-insert (DC-no insert) were made for immunization materials, and murine uterine cervical cancer cell line coexpressing E7, firefly luciferase, hNIS, and EGFP genes (TC-1/FNG) were prepared for the animal tumor model. C57BL/6 mice were divided into five therapy groups (phosphate-buffered saline [PBS], DC-no insert, DC-E7, I-131, and DC-E7+I-131 groups). Single therapy with either DC-E7 or I-131 induced greater retardation in tumor growth compared with PBS or DC-no insert groups, and it resulted in some tumor-free mice (DC-E7 and I-131 groups, 40% and 20%, respectively). Combination therapy with DC-E7 and I-131 dramatically inhibited tumor growth, thus causing complete disappearance of tumors in all mice, and these effects were further confirmed by BLI in vivo. In conclusion, complete disappearance of the tumor was achieved with combined DC-E7 vaccination and hNIS radioiodine gene therapy in a mouse model with E7-expressing uterine cervical cancer, and serial BLIs successfully demonstrated antitumor effects in vivo.

Immunolabelling of the inhibin/activin-βC subunit in normal and malignant human uterine cervical tissue and cervical cancer cell lines

Inhibins are dimeric glycoproteins, composed of an α-subunit and one of two possible β-subunits (βA or βB), with substantial roles in human reproduction and in endocrine-responsive tumours. Recently a novel β subunit named βC was described, although it is still unclear if normal or cancerous cervical epithelial cells as well as cervical cancer cell lines can synthesise the inhibin-βC subunit. Four normal cervical tissue samples together with specimens of well-differentiated squamous cervical cancer and adenocarcinoma of the cervix were immunohistochemically analyzed. Additionally, two cervical carcinoma cell lines (HeLa and CaSKi) were analyzed by immunofluorescence for the expression of this novel subunit. We demonstrated for the first time an immunolabelling of the inhibin-βC subunit in normal and malignant cervical tissue, as well as cervical cancer cells. Although the physiological role is still unclear in cervical tissue, the inhibin-βC subunit might play important roles in carcinogenesis. Moreover, the synthesis of this subunit in cervical carcinoma cell lines of squamous and epithelial origins allows the use of these cell lines in elucidating its functions in cervical pathogenesis.

Macrophage migration inhibitory factor expression in cervical cancer

The glycoprotein macrophage migration inhibitory factor (MIF) is a cytokine that has been shown to promote tumor progression and tumor immune escape in ovarian cancer. The present study investigates MIF in uterine cervical cancer. Eighty surgical biopsies (32 cervical dysplasias, 23 in situ carcinomas and 25 invasive carcinomas) of uterine cervical tissue were evaluated immunohistochemically for MIF expression. In uterine cervical cancer cell lines SiHa and CaSki and their respective supernatants, MIF protein expression was analyzed by Western blotting, enzyme-linked immunosorbent assay (ELISA) and reverse transcriptase polymerase chain reaction (RT-PCR). Immunohistochemical analysis shows that MIF is clearly overexpressed on the protein level in invasive cervical cancer compared to cervical dysplasias. MIF overexpression was confirmed by RT-PCR in surgical biopsies of invasive cervical cancer. Western blotting reveals that the MIF protein is overexpressed in SiHA und CaSki cervical cancer cell lines, whereas the ELISA reveals that cervical cancer cells secrete MIF. MIF has been shown to promote tumor immune escape mechanisms in other cancer entities, which makes it an interesting target for cancer therapy, given the known significance of immune mechanisms for uterine cervical cancer. The overexpression of MIF on the protein and mRNA level, as well as its secretion by cervical cancer cells points to a critical role of the protein for the pathogenesis of uterine cervical cancer.

The establishment and characterization of a continuous cell line of mouse cervical carcinoma

To establish a murine uterine cervical cancer cell line and to define its biological characters. Transplanted tumor tissue was used for in vitro primary culture of U14 cervical carcinoma cells. After 20 passages, we examined its morphology, chromosomes, tumorigenicity and produced a growth curve. CK was detected by immunohistochemistry, the cell cycle determined by flow cytometry and the metastatic potential assessed in 615 and C57BL/c mice. We also transfected the cells with the pEGFP-N1 plasmid. A newly established murine cell line was passaged 50 times over a period of 10 months. The cells grow as a partially suspended culture, and are immunohistochemically CK(+). The cell line is characterized by a hypotetraploid karyotype, a chromosomal number of 64–68 and a doubling time of 21.8 h. Exponential growth occurs by the third and forth day of culture. Cell cycle analysis showed G1 34%, G2 26%, and 40% in the S phase. The tumorigenicity was 100% upon implantation. No mycoplasma contamination was detected. A monoclonal continuous U14-GFP cell strain which was 100% GFP (+) was also produced. We successfully established a new murine cervical U14 carcinoma cell line and an U14-GFP monoclonal strain. These cell lines are ideal for combined in vivo and in vitro tumor research.

Influences of cyclooxygenase-1 and -2 expression on the radiosensitivities of human cervical cancer cell lines

We utilized three cervical cancer cell lines (HeLa, HT-3, and C33A) and clonogenic assays to determine whether cyclooxygenase (COX) expression is related to radiosensitivity. Using COX DNA transfection and COX inhibition by siRNA, we also examined changes in radiosensitivity caused by variations in COX expression. The survival fractions of HeLa and HT-3 cell lines, which both with COX-1 and COX-2 activity, were found to be significantly higher than that of the C33A cell line which had neither COX-1 nor COX-2 activity. Moreover, the acquisition of COX-1 in C33A cell line significantly reduced its radiosensitivity, but COX-2 transfection increased radiosensitivity in this cell line. In addition, the inhibition of COX-1 activity in HT-3 cell line using siRNA resulted in an increased radiosensitivity, but this phenomenon was not observed for COX-2 inhibition. The same experiment in HeLa cells using siRNA also showed no significant change in radiosensitivity. The results obtained during this study suggest that COX expression is associated with the radiosensitivity in uterine cervical cancer cell lines and COX-1 might have more important role than COX-2.

Overexpression ofLAMP3/TSC403/DC-LAMPPromotes Metastasis in Uterine Cervical Cancer

LAMP3 (DC-LAMP, TSC403, CD208) was originally isolated as a gene specifically expressed in lung tissues. LAMP3 is located on a chromosome 3q segment that is frequently amplified in some human cancers, including uterine cervical cancer. Because two other members of the LAMP family of lysosomal membrane glycoproteins, LAMP1 and LAMP2, were previously implicated in potentially modulating the interaction of vascular endothelial and cancer cells, we hypothesized that LAMP3 might also play an important part in metastasis. To clarify the metastatic potential of LAMP3 in cervical cancers, we transfected a LAMP3 expression vector into a human uterine cervical cancer cell line, TCS. In an in vitro invasion assay, the migration of LAMP3-overexpressing TCS cells was significantly higher than in control TCS cells. In an in vivo metastasis assay, distant metastasis was detected in 9 of 11 LAMP3-overexpressing TCS cell-injected mice and in only 1 of 11 control mice. Histologic study showed that LAMP3-overexpressing cells readily invaded into the lymph-vascular space. In clinical samples, quantitative real-time reverse transcription-PCR (RT-PCR) analyses showed that LAMP3 mRNA was significantly up-regulated in 47 of 47 (100%) cervical cancers and in 2 of 15 (13%) cervical intraepithelial neoplasias, compared with a low level of LAMP3 mRNA expressed in normal uterine cervixes. Interestingly, high LAMP3 expression was significantly correlated with the overall survival of patients with stage I/II cervical cancers. These findings indicate that LAMP3 overexpression is associated with an enhanced metastatic potential and may be a prognostic factor for cervical cancer.

Photogem Induces Necrosis in Various Uterine Cervical Cancer Cell Lines by PDT

In order to elucidate the antitumor effect of photodynamic therapy (PDT), using a derivative of the photosensitizing agent hematoporphyrin (Photogem) and a diode laser, the cell death of uterine cancer cell lines (CaSki, HT3, HeLa, and SKOV-3), and mice transplanted with TC-1 lung cancer cells, were evaluated. The morphological changes, MTT assay, flow cytometry, cytotoxicity and tumor growth inhibition study were evaluated at various time intervals after the PDT. The results showed that the survival rates of each cell line decreased with time and dose response after performing the PDT. Also, the PDT-induced damage of cancer cells was almost entirely confined to necrosis of the tumor cells in the early time courses. The irradiation of CaSki cells in the presence of Photogem induced plasma membrane disruption and cell shrinkage, indicating the plasma membrane as the main target for Photogem. In the in vivo experiment, significantly longer survival and a significantly smaller tumor size were seen over the time courses of the Photogem with irradiation compared to the untreated control groups; resorption of the tumor was also observed after the PDT treatment. Collectively, our results indicated that Photogem possesses anti-tumor effects, and necrosis-like death, with plasma membrane damage, was postulated to be the principal mechanism of the antitumor effect of the PDT using Photogem.

A Free Radical Initiator, 2,2′-azobis (2-aminopropane) Dihydrochloride Enhances Hyperthermia-induced Apoptosis in Human Uterine Cervical Cancer Cell Lines

Hyperthermia-induced apoptosis and its enhancement in the presence of a temperature-dependent free radical initiator, 2,2′-azobis (2-aminopropane) dihydrochloride (AAPH) were examined in human uterine cervical cancer cell lines, CaSki and HeLa. When both cell lines were treated with hyperthermia at 44°C for 60 min, minimal apoptosis was observed. When combined with nontoxic AAPH (50 mM), significant enhancement of apoptosis was observed, where the initial rate of free radical formation was about twice as high than that at 37°C. Augmentation of the growth delay, lipid peroxidation (LPO), activation of caspase-3 and increase in [Ca2+]i were also observed after the combined treatment. A water-soluble vitamin E, Trolox, blocked the increase in [Ca2+]i and an intracellular Ca2+ chelator, BAPTA-AM, prevented the DNA fragmentation induced by the combination. Cytochrome c release was also revealed by fluorescence microscopy. However, no significant change in mitochondrial membrane potential and expression of Bax and Bcl-2 was observed. A slight increase in Fas expression was observed only in CaSki cells after the combined treatment. These results indicate that hyperthermia and AAPH induce enhanced apoptosis and subsequent cell killing via two pathways; a pathway dependent on increase in LPO and [Ca2+]i, and a pathway associated with cytochrome c release and subsequent caspase activation without changes of mitochondrial membrane potential and Bax/Bcl-2 expression in these cell lines. Since it is known that cancer cells are generally resistant to physical and chemical stress-induced apoptosis, free radical generators like AAPH appear to be a useful thermosensitizer for hyperthermic cancer therapy.