9 research outputs found
Estrogen Receptor Alpha Expression in Ovarian Cancer Predicts Longer Overall Survival
Estrogen as a potential factor of ovarian carcinogenesis, acts via two nuclear receptors, estrogen receptor alpha (ERα) and estrogen receptor beta (ERβ), but the cellular signal pathways involved are not completely clear so far. In this study we have described the expression of ERα, detected by immunocytochemistry in 11 ovarian carcinoma cell lines and by immunohistochemistry in 43 Federation Internationale des Gyneacologistes et Obstetristes stage III ovarian carcinoma specimens prepared before and after treatment with cisplatin-based schemes. For cisplatin resistance is a major obstacle in the treatment of ovarian carcinoma, analysis of cisplatin sensitivity in 11 ovarian carcinoma cell line was also performed. The strong nuclear ERα expression was only shown in the single A2780P cell line. Expression of ERα in tissue specimens did not reveal any correlations between histopathological parameters (histologic type and grading). We demonstrated a significant association with ERα expression in specimens from primary laparotomies (PL) and cause–specific survival. In the cases terminated by death of the patient, overall immunoreactivity score of ERα expression at PL was significantly lower than in surviving patients. In addition, Kaplan-Meier analysis revealed significantly shorter overall survival time and progression-free time in cases with lower immunoreactivity score of ERα expression at PL. Our findings support the hypothesis that aberrant hormone activity, by way of altered receptor expression, might be an important factor in the malignant transformation of ovarian cancer
Bedeutung des ABC-Transporters MRP2/cMOAT/ABCC2 bei der Cisplatinresistenz humaner Tumorzellen
Tumorzellen können vielfältige Resistenzmechanismen gegenüber Zytostatika entwickeln. Untersuchungen an drei humanen Tumorzellinien und ihren cisplatinresistenten Varianten zeigten eine Assoziation von erhöhter MRP2-Expression und dem Auftreten von Cisplatinresistenz. Darüberhinaus waren die cisplatinresistenten Zellinien gegenüber Carboplatin kreuzresistent. Um weitere Faktoren im Zusammenhang mit der Cisplatinresistenz zu untersuchen, wurde der Mutationsstatus von p53 und der zelluläre Glutathiongehalt in den Zellinien bestimmt. Der offene Leserahmen von MRP2 aus der cisplatinresistenten Ovarialkarzinomzellinie A2780RCIS wurde für die Transfektion in die cisplatinsensitive Zellinie A2780 genutzt. Die Transfektanten zeigten eine Überexpression von MRP2 und wiesen eine Resistenz gegenüber Cisplatin und Carboplatin auf. Dies konnte in Zellzyklus- und Apoptose-Untersuchungen unter Cisplatinbehandlung gestätigt werden. Durch computergestützte Faltungsanalysen von Abschnitten der MRP2-mRNA wurden zwei potentielle Ribozymschnittstellen ausgewählt. Die konstruierten Anti-MRP2-Hammerhead-Ribozyme RzM1 und RzM2 wurden im zellfreien System auf ihre Schnittaktivität getestet und erwiesen sich als katalytisch aktiv. Es wurden verschiedene kinetische Parameter für RzM1 und RzM2 ermittelt und mit anderen Ribozymen verglichen. Die Ribozyme zeigten eine gute Effektivität bei der Spaltung ihres Zielmoleküls, wobei RzM1 die höhere Effektivität aufwies. Beide Ribozyme wurden auf ihre Wirksamkeit durch Transfektion in die Zellinie A2780RCIS getestet. Die untersuchten Transfektanten zeigten eine geringere Expression von MRP2 auf mRNA- und Proteinebene und wiesen eine verminderte Resistenz gegenüber Cisplatin, Carboplatin, Daunorubicin und Etoposid auf. Die Ribozyme RzM1 und RzM2 waren gleichermaßen für die Expressionsregulierung von MRP2 in Tumorzellen geeignet. In Zellzyklus- und Apoptose-Untersuchungen wurde funktionell bestätigt, daß die A2780RCIS-Anti-MRP2-Ribozym-Transfektanten auf eine Cisplatinbehandlung stärker ansprechen als die cisplatinresistente Ausgangszellinie A2780RCIS. Die Anwendung der Ribozyme RzM1 und RzM2 zur Unterstützung der Chemotherapie von Tumorzellen scheint daher vielversprechend.Tumour cells can develop a lot of resistance mechanisms against cytostatic drugs. Examinations of three human tumour cell lines and their cisplatinresistant variants showed an association of elevated MRP2 expression and the occurrance of cisplatinresistance. Moreover, the cisplatinresistant cell lines were crossresistant against carboplatin. To examine further factors in context of cisplatinresistance the mutation status of p53 and the cellular glutathione content of the cell lines were determined. The MRP2-open reading frame of the cisplatinresistant ovarian carcinoma cell line A2780RCIS was used for transfection into the cisplatinsensitive cell line A2780. The transfectants showed an overexpression of MRP2 and a resistance against cisplatin and carboplatin. This could be confirmed with analysis of the cell cycle and apoptosis induction after treatment with cisplatin. Using computer aided folding analysis of MRP2 mRNA parts two possible ribozyme cleavage sites were selected. The constructed anti-MRP2 hammerhead ribozymes RzM1 and RzM2 were tested in a cell-free system with respect to their cleavage activities and were found to be catalytic active. Various kinetic parameters of RzM1 and RzM2 were determined and compared with other ribozymes. The ribozymes showed a good effectivity for the substrate cleavage, although RzM1 had the better effectivity. Both ribozymes were tested for their effectiveness after transfection into the cell line A2780RCIS. The transfectants showed a lower MRP2 expression on mRNA and protein level and also a reduced resistance against cisplatin, carboplatin, daunorubicin, and etoposide. The ribozymes RzM1 and RzM2 were both equally suitable for the regulation of MRP2 expression in tumour cells. Analysis of cell cycle and apoptosis induction could confirm functionally the higher sensitivity of the A2780RCIS-anti-MRP2 ribozyme transfectants after treatment with cisplatin in comparison to the cisplatinresistant cell line A2780RCIS. Therefore, the application of the ribozymes RzM1 and RzM2 for the support of cancer chemotherapy seems to be promising
Impact of restricted contact between grandparents and grandchildren during the COVID-19 pandemic
To combat the COVID-19 pandemic strict contact restrictions have been imposed on institutions for both older and younger people, social structures have been locked down, families have been urged to reduce contact with older relatives, and people over 65 have been temporarily banned from their workplaces and from attending events, both in public and private spaces. These measures are assumed to have a number of psychosocial consequences. For this questionnaire study, 268 pupils (7-to-10 years-old) of nine different schools in Hamburg, Germany, with different social index were asked about how they experienced, perceived, and behaved during the COVID-19 pandemic. 75% of the children reported on restricted contact to their grandparents: While 41% did not meet their grandparents at least for a certain time at the beginning of the pandemic, 34% did not meet their grandparents during the whole first year of the pandemic. Of those who met their grandparents, 25% kept physical distance to them. These contact restrictions were significantly higher in schools with a lower social index, chi2(8)=15.49, p=.05. Those children who never met their grandparents also reported on higher perceived stress, t(220)=-2.37, p=.019, d=-.33, tended to have lower subjective well-being, t(223)=-1.73, p=.09, d=-.24, and had higher risk perceptions concerning COVID-19 infections, t(223)=-2.18, p=.03, d=-.31. Hence social isolation and loneliness is not only an issue for older people themselves, but contact restrictions also potentially increase the stress load and impair the well-being of children who have to do without support and care of their grandparents in sensitive developmental phases
Decreased expression of p16 in ovarian cancers represents an unfavourable prognostic factor
Decreased expression of p16 may result from
hypermethylation of the promoter or from deletion of the
gene. It can lead to intensified proliferation of neoplastic
cells and to cytostatic drug resistance. The study was
aimed at the examination of prognostic value of p16
expression in relation to Ki67 and caspase-3 in ovarian
cancers using immunohistochemistry. The immunohistochemical
studies were performed on 73 paraffinembedded
samples of ovarian cancers from 43 patients
and samples from 6 healthy ovaries. We have used
monoclonal antibodies against p16. ABC method and
DAB were used for antigens visualisation. The intensity
of the immunohistochemical reactions was appraised
using the semi-quantitative IRS scale. In healthy ovaries
we have shown strong reaction in the nuclei of surface
epithelium. In the case of studied ovarian cancers, the
reaction of a nuclear and cytoplasmic localization was
obtained. The mean overall immunoreactivity score of
nuclear p16 expression amounted to 5.30±3.44 SD in
primary laparotomy material and 6.61±4.34 SD in
secondary cytoreduction material. Statistical analysis
demonstrated that lower p16 expression was typical of
the younger patients and the patients who died. Kaplan-
Meier’s analysis proved that lower expression of p16
was characteristic of cases with shorter overall survival.
In the present study we have demonstrated that lowered
p16 expression represented an unfavourable prognostic
index in ovarian cancer. Lowered p16 expression was
also typical for chemotherapy-resistant ceases (cases of
lower caspase-3 and higher Ki67 at secondary
cytoreduction expression)