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Cervical Carcinoma Cells (cervical + carcinoma_cell)
Selected AbstractsEnhanced expression of Mcm proteins in cancer cells derived from uterine cervixFEBS JOURNAL, Issue 6 2003Yukio Ishimi Minichromosome maintenance proteins (Mcm) 2,7 play essential roles in eukaryotic DNA replication. Several reports have indicated the usefulness of Mcm proteins as markers of cancer cells in histopathological diagnosis. However, their mode of expression and pathophysiological significance in cancer cells remain to be clarified. We compared the level of expression of Mcm proteins among human HeLa uterine cervical carcinoma cells, SV40-transformed human fibroblast GM00637 cells and normal human fibroblast WI-38 cells. All the proteins examined were detected in HeLa and GM cells at 6,10 times the level found in WI-38 cells on average. This increase was observed both in total cellular proteins and in the chromatin-bound fraction. Consistently, Mcm2 mRNA was enriched in HeLa cells to approximately four times the level in WI-38 cells, and the synthesis of Mcm4, 6 and 7 proteins was accelerated in HeLa cells. Immunohistochemical studies of surgical materials from human uterine cervix showed that Mcm3 and 4 are ubiquitously expressed in cancer cells. Further, the positive rate and level of Mcm3 and 4 expression appeared to be higher in cancer cells than in normal proliferating cells of the uterine cervix and dysplastic cells, suggesting that they can be useful markers to distinguish these cells. [source] Epidermal growth factor receptor expression affects the efficacy of the combined application of saponin and a targeted toxin on human cervical carcinoma cellsINTERNATIONAL JOURNAL OF CANCER, Issue 6 2010Diana Bachran Abstract Cervical cancer is the second most common cancer in women worldwide. Targeting the epidermal growth factor receptor (EGFR) is a very promising approach since it is overexpressed in about 90% of cervical tumors. Here, we quantified the toxic effect of SE, a targeted toxin consisting of epidermal growth factor (EGF) as targeting moiety and the plant toxin saporin-3, on 3 common human cervical carcinoma cell lines (HeLa, CaSki and SiHa) and recently established lines (PHCC1 and PHCC2) from 2 different individuals. A human melanocytic and a mouse cell line served as negative control. Additionally, we combined SE with saponinum album, a saponin composite from Gypsophila paniculata, which exhibited synergistic properties in previous studies. The cell lines, except for SiHa cells, revealed high sensitivity to SE with 50% cell survival in the range of 5,24.5 nM. The combination with saponin resulted in a remarkable enhancement of cytotoxicity with enhancement factors ranging from 9,000-fold to 2,500,000-fold. The cytotoxicity of SE was clearly target receptor specific since free EGF blocks the effect and saporin-3 alone was considerably less toxic. For all cervical carcinoma cell lines, we evinced a clear correlation between EGFR expression and SE sensitivity. Our data indicate a potential use of targeted toxins for the treatment of cervical cancer. In particular, the combination with saponins is a promising approach since efficacy is drastically improved. [source] Genetic redundancy in human cervical carcinoma cells: Identification of cells with "normal" propertiesINTERNATIONAL JOURNAL OF CANCER, Issue 10 2007Anastasia Bachmann Abstract Although it is generally assumed that cancer arises from a singular cell, a tumor must be considered as a dynamic and emergent biological structure, whose organizing principle is determined by genetic and epigenetic modifications, occurring variably in response to microenvironmental selection conditions. As previously shown, HPV-positive cervical carcinoma cells have lost their ability to induce IFN-, upon TNF-, treatment. However, regarding cancer as a non-linear system, which may, even in the absence of an apparent selection pressure, fluctuate between different "metastable" phenotypes, we demonstrate that TNF-, mediated IFN-, induction is not irreversibly disturbed in all cells. Using the IFN-, sensitive Encephalomyocarditis virus (EMCV) as a tool to monitor antiviral activity in long-term established malignant HeLa cells, rare IFN-, expressing clones were rescued from a population of non-responsive and EMCV-sensitive cells. Antiviral activity was mediated by the re-expression of IRF-1 and p48 (IRF-9), both key regulatory molecules normally found to be suppressed in cervical carcinoma cells. Upon inoculating of selected clones into immunocompromised animals, a reduced or even an absence of tumorigenicity of initially highly malignant cells could be discerned. These data indicate that both the absence of interferon signaling and the ability to form tumors were reversed in a minority of cells. We provide a paradigm for the existence of innate genetic redundancy mechanisms, where a particular phenotype persists and can be isolated without application of drugs generally changing the epigenetic context. © 2007 Wiley-Liss, Inc. [source] Non-apoptogenic killing of hela cervical carcinoma cells after short exposure to the alkylating agent N -methyl- N, -nitro- N -nitrosoguanidine (MNNG)JOURNAL OF CELLULAR BIOCHEMISTRY, Issue 6 2003Józefa W, sierska-G Abstract We examined the action of N -methyl- N, -nitro- N -nitrosoguanidine (MNNG) on HeLa cells and compared it with that of cisplatin (CP). MNNG directly killed a substantial number of cells within 1 hour and resulted in strong DNA-damage as evidenced by Comet measurements. Despite appearance of DNA lesions, p53 protein was not activated. Analysis of HeLa cells treated with MNNG for 1h, 3h and 6h by flow cytometry and by Hoechst staining did not reveal any sub-G1 cell population and chromatin condensation/fragmentation characteristic for apoptosis, respectively. Also, no biochemical changes typical for apoptosis such as activation of caspase-3 or release of cytochrome C from mitochondria were detected. Inactivation of PARP-1 reduced the direct cytotoxicity exerted by MNNG. Our results showing that despite appearance of severe DNA lesions after short exposure of HeLa cells to MNNG neither activation of p53 response nor induction of apoptosis occurred implicate that generation of strong DNA damage is not sufficient to stabilize p53 protein in HeLa cells. Our data unequivocally show that the conscientious determination of the type of cell death induced by genotoxic agents is necessary. The assessment of the changes based on at least a few independent criteria is required to discriminate between apoptosis and necrosis. Since the alkylating agents generate DNA strand breaks, the recruitment of methods based on determination of DNA cleavage such as DNA ladder or TUNEL assay for evaluation of apoptosis is not adequate. © 2003 Wiley-Liss, Inc. [source] Senescence-associated ,-galactosidase is lysosomal ,-galactosidaseAGING CELL, Issue 2 2006Bo Yun Lee Summary Replicative senescence limits the proliferation of somatic cells passaged in culture and may reflect cellular aging in vivo. The most widely used biomarker for senescent and aging cells is senescence-associated ,-galactosidase (SA-,-gal), which is defined as ,-galactosidase activity detectable at pH 6.0 in senescent cells, but the origin of SA-,-gal and its cellular roles in senescence are not known. We demonstrate here that SA-,-gal activity is expressed from GLB1, the gene encoding lysosomal ,-D-galactosidase, the activity of which is typically measured at acidic pH 4.5. Fibroblasts from patients with autosomal recessive GM1 -gangliosidosis, which have defective lysosomal ,-galactosidase, did not express SA-,-gal at late passages even though they underwent replicative senescence. In addition, late passage normal fibroblasts expressing small-hairpin interfering RNA that depleted GLB1 mRNA underwent senescence but failed to express SA-,-gal. GLB1 mRNA depletion also prevented expression of SA-,-gal activity in HeLa cervical carcinoma cells induced to enter a senescent state by repression of their endogenous human papillomavirus E7 oncogene. SA-,-gal induction during senescence was due at least in part to increased expression of the lysosomal ,-galactosidase protein. These results also indicate that SA-,-gal is not required for senescence. [source] Germ cell-specific heat shock protein 70-2 is expressed in cervical carcinoma and is involved in the growth, migration, and invasion of cervical cellsCANCER, Issue 16 2010Manoj Garg PhD Abstract BACKGROUND: Cervical cancer is a major cause of death among women worldwide, and the most cases are reported in the least developed countries. Recently, a study on DNA microarray gene expression analysis demonstrated the overexpression of heat shock protein 70-2 (HSP70-2) in cervical carcinoma cells (HeLa). The objective of the current study was to evaluate the association between HSP70-2 expression in cervical carcinogenesis and its potential role in various malignant properties that result in disease progression. METHODS: HSP70-2 expression was examined in various cervical cancer cell lines with different origins and in clinical cervical cancer specimens by reverse transcriptase-polymerase chain reaction (RT-PCR), flow cytometry, and immunohistochemistry (IHC) analyses. A plasmid-based, short-hairpin RNA approach was used specifically to knock down the expression of HSP70-2 in cervical tumor cells in vitro and in vivo to examine the role of HSP70-2 on various malignant properties. RESULTS: RT-PCR and IHC analyses revealed HSP70-2 expression in 86% of cervical cancer specimens. Furthermore, knockdown of HSP70-2 expression significantly reduced cellular growth, colony formation, migration, and invasion in vitro and reduced tumor growth in vivo. A significant association of HSP70-2 gene and protein expression was observed among the various tumor stages (P = .046) and different grades (P = .006), suggesting that HSP70-2 expression may be an indicator of disease progression. CONCLUSIONS: The current findings suggested that HSP70-2 may play an important role in disease progression in cervical carcinogenesis. Patients who had early stage disease and low-grade tumors had HSP70-2 expression, supporting its potential role in early detection and aggressive treatment modalities for cervical cancer management. Cancer 2010. © 2010 American Cancer Society. [source] Role of tumor-derived proinflammatory cytokines GM-CSF, TNF-,, and IL-12 in the migration and differentiation of antigen-presenting cells in cervical carcinomaCANCER, Issue 3 2007Henry J.M.A.A. Zijlmans MD Abstract BACKGROUND. Proinflammatory cytokines are important in modifying the activity, differentiation, and migration of antigen-presenting cells and may influence the survival of cancer patients. The study assessed whether GM-CSF, TNF-,, and IL-12, produced by cervical cancer cells, are important for the activity, differentiation, and migration of antigen-presenting cells. METHODS. In 90 patients with cervical carcinoma the number of monocytes/tumor-associated macrophages (TAM), mature dendritic cells (DC), and Langerhans cells (LHC) was determined using immunohistochemistry. An RNA in situ hybridization technique was used to measure the expression level of GM-CSF, TNF-,, IL-12p35, and IL-12p40. RESULTS. TAM were detected intraepithelial as well as in the stroma of the tumor. LHC were only detected intraepithelial and mature DC only in the tumor stroma. The number of TAM correlated positively with the number of mature DC. The expression levels of GM-CSF and TNF-, correlated positively with the number of TAM and DC. TNF-, showed a negative correlation with the number of LHC. A significant correlation between the expression of functional IL-12 (IL-12p40) and stromal TAM was found. The expression of GM-CSF, TNF-,, and IL-12p40 did not correlate significantly with disease-free survival. However, high IL-12p40 expression was associated with a favorable cumulative overall survival. CONCLUSIONS. The results suggest that GM-CSF as well as TNF-,, produced by cervical carcinoma cells, may play a role in the differentiation of monocytes into mature DC. Furthermore, TNF-, may influence the migration of LHC from the tumor. Cancer 2007;109:556,565. © 2007 American Cancer Society. [source] Expression of FasL in squamous cell carcinomas of the cervix and cervical intraepithelial neoplasia and its role in tumor escape mechanism,CANCER, Issue 5 2006Ramy Ibrahim M.D. Abstract BACKGROUND To date, several mechanisms have been described by which malignant cells escape from the immune system. One of these is through the expression of FasL. The authors hypothesized that the Fas/FasL interaction enables cervical carcinoma cells to induce apoptosis of the cells of the immune system and thereby escape from them. METHODS The authors tested the expression of FASL on the surface of cervical carcinoma tissues. Next, they stained the same cervical tissues with anti-human leukocyte common antigen and TUNEL to identify apoptotic cells. An in vitro functional assay was then done to test if the FASL expressed on the surface of cervical carcinoma cell lines was or was not responsible for inducing apoptosis in T-cells. Finally, they compared the expression of FASL on normal and dysplastic cervical tissues. RESULTS Ninety-four percent of the cervical carcinoma tissues the authors tested expressed FasL and the majority of the apoptotic cells in the specimens were leukocytes with very few tumor cells. In the in vitro functional assay, only the Fasl expressing cell line and not the Fasl negative cell line was able to induce apoptosis of the Fas-expressing Jurkat cells. On examining the normal cervical tissues, the authors found that the expression of Fasl was confined to the basal cell layer with loss of expression observed in the suprabasal layers, which made it an immune privileged site. Conversely, there was persistent expression of FasL in the dysplastic layers in cervical dysplasia and squamous cell carcinoma specimens. CONCLUSIONS The findings of the current study support the authors' hypothesis that persistent expression of FasL plays a role in the ability of cervical carcinoma cells to escape from the immune system. Cancer 2006. Published 2006 by the American Cancer Society. [source] Investigation into the effects of cidofovir on an in vitro model of recurrent respiratory papillomatosisCLINICAL OTOLARYNGOLOGY, Issue 3 2006A.J. Donne Problem. Recurrent respiratory papillomatosis (RRP) has no cure, and cidofovir is currently the most contemporary adjuvant treatment. Cidofovir has reported activity against Human Papilloma Virus type 16, but no laboratory studies have yet been performed on HPV type 6 which is the main cause of RRP. This work describes the generation of a novel HPV 6 related cell line and its use to evaluate the effects of Cidofovir. Method. HPV6b E6 cDNA was stably introduced into HPV negative C33A cervical carcinoma cells to produce the C33AT6E6 cell line. Two different doses of Cidofovir were applied to parent C33A, C33AT6E6 and C33AT16E6 (type 16 cell line) with appropriate controls. Growth and FACS cell cycle analysis were performed after 3 and 6 days of continuous exposure followed by 2 and 3 days post-drug withdrawal. Result.PCR analysis confirmed HPV6 E6 expression in C33AT6E6 cells. High dose cidofovir was toxic at 3 and 6 days exposure in all cells tested. Low dose exposure was toxic for C33AT16E6 cells at 3 days whereas C33A and C33AT6E6 only showed minimal toxicity at 6 days. C33A and C33AT6E6 cells also showed earlier recovery following drug withdrawal. Conclusion.Cidofovir showed varying degrees of non-specific toxicity against all three cell lines tested. However, HPV16 E6 expressing cells were more sensitive than either parent or HPV6 E6 expressing cells indicating that cidofovir has no selective advantage for the RRP related HPV6 E6 expressing cell line. [source] | |||||||||||||