Q66311625
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Závěrečná zpráva o řešení grantu Interní grantové agentury MZ ČR
Přeruš. str. : il. ; 32 cm
Cílem je objasnění genetických a z nich vyplývajících biochemických aberací antionkogenů a genů podílejících se na řízení buněčné proliferace.
Závěrečná zpráva o řešení grantu Interní grantové agentury MZ ČR
Přeruš. str. : il. ; 32 cm
Přenos genů jako nástroj imortalizace normálních i nádorových epiteliálních buněk a předpoklad genové terapie. XXX XXX XXX
Závěrečná zpráva o řešení grantu Interní grantové agentury MZ ČR
Přeruš. str. : il. ; 32 cm
Molekulárně genetická, imunochemická a funkční analýza antionkogenů ve vztahu k patogeneze solidních nádorů. XXX XXX XXX
- MeSH
- monoklonální protilátky MeSH
- nádory etiologie imunologie MeSH
- protilátky nádorové MeSH
- tumor supresorové geny analýza MeSH
- Konspekt
- Patologie. Klinická medicína
- NLK Obory
- onkologie
- embryologie a teratologie
- genetika, lékařská genetika
- NLK Publikační typ
- závěrečné zprávy o řešení grantu IGA MZ ČR
Závěrečná zpráva o řešení grantu Interní grantové agentury MZ ČR
Přeruš. str. : il. ; 32 cm
Monoklonální protilátky proti onkoproteinům a diferenciačním antigenům: příprava a využití v onkologické diagnostice. XXX XXX XXX
- MeSH
- imunohistochemie MeSH
- monoklonální protilátky MeSH
- nádory diagnóza MeSH
- onkogenní proteiny MeSH
- Konspekt
- Patologie. Klinická medicína
- NLK Obory
- alergologie a imunologie
- onkologie
- NLK Publikační typ
- závěrečné zprávy o řešení grantu IGA MZ ČR
The DNA damage checkpoints provide an anti-cancer barrier in diverse tumour types, however this concept has remained unexplored in prostate cancer (CaP). Furthermore, targeting DNA repair defects by PARP1 inhibitors (PARPi) as a cancer treatment strategy is emerging yet requires suitable predictive biomarkers. To address these issues, we performed immunohistochemical analysis of multiple markers of DNA damage signalling, oxidative stress, DNA repair and cell cycle control pathways during progression of human prostate disease from benign hyperplasia, through intraepithelial neoplasia to CaP, complemented by genetic analyses of TMPRSS2-ERG rearrangement and NQO1, an anti-oxidant factor and p53 protector. The DNA damage checkpoint barrier (γH2AX, pATM, p53) mechanism was activated during CaP tumorigenesis, albeit less and with delayed culmination compared to other cancers, possibly reflecting lower replication stress (slow proliferation despite cases of Rb loss and cyclin D1 overexpression) and progressive loss of ATM activator NKX3.1. Oxidative stress (8-oxoguanine lesions) and NQO1 increased during disease progression. NQO1 genotypes of 390 men did not indicate predisposition to CaP, yet loss of NQO1 in CaP suggested potential progression-opposing tumour suppressor role. TMPRSS2-ERG rearrangement and PTEN loss, events sensitizing to PARPi, occurred frequently along with heterogeneous loss of DNA repair factors 53BP1, JMJD1C and Rev7 (all studied here for the first time in CaP) whose defects may cause resistance to PARPi. Overall, our results reveal an unorthodox DNA damage checkpoint barrier scenario in CaP tumorigenesis, and provide novel insights into oxidative stress and DNA repair, with implications for biomarker guidance of future targeted therapy of CaP.
- MeSH
- fosfohydroláza PTEN analýza genetika MeSH
- fúzní onkogenní proteiny analýza genetika MeSH
- genotyp MeSH
- lidé středního věku MeSH
- lidé MeSH
- NAD(P)H dehydrogenasa (chinon) analýza genetika MeSH
- nádory prostaty genetika metabolismus patologie MeSH
- oprava DNA MeSH
- oxidační stres * MeSH
- poškození DNA * MeSH
- progrese nemoci MeSH
- prostata metabolismus patologie MeSH
- regulace genové exprese u nádorů MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- Check Tag
- lidé středního věku MeSH
- lidé MeSH
- mužské pohlaví MeSH
- senioři nad 80 let MeSH
- senioři MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
NQO1 participates in cellular defense against oxidative stress and regulates apoptosis via p53- and NFB-mediated pathways. We have previously found that homozygous missense variant NQO1*2 (rs1800566) predicts poor survival among breast cancer patients, particularly after anthracycline-based adjuvant chemotherapy. Here, we investigated NQO1 and NFB protein expression and global gene expression profiles in breast tumors with correlation to tumor characteristics and survival after adjuvant chemotherapy. We used immunohistochemical analysis of tissue microarrays to study NQO1 and NFB expression in two series of tumors: 1000 breast tumors unselected for treatment and 113 from a clinical trial comparing chemotherapy regimens after anthracycline treatment in advanced breast cancer. We used gene expression arrays to define genes co-expressed with NQO1 and NFB. NQO1 and nuclear NFB were expressed in 83% and 11% of breast tumors, and correlated inversely (P = 0.012). NQO1 protein expression was associated with estrogen receptor (ER) expression (P = 0.011), whereas 34.5% of NFB-nuclear/activated tumors were ER negative (P = 0.001). NQO1 protein expression and NFB activation showed only trends, but no statistical significance for patient survival or outcome after anthracycline treatment. Gene expression analysis highlighted 193 genes that significantly correlated with both NQO1 and NFB in opposite directions, consistent with the expression patterns of the two proteins. Inverse correlation was found with genes related to oxidation/reduction, lipid biosynthesis and steroid metabolism, immune response, lymphocyte activation, Jak-STAT signaling and apoptosis. The inverse relationship between NQO1 protein expression and NFB activation, underlined also by inverse patterns of association with ER and gene expression profiles of tumors, suggests that NQO1-NFB interaction in breast cancer is different from several other tissue types, possibly due to estrogen receptor signaling in breast cancer. Neither NQO1 nor NFB protein expression appear as significant prognostic or predictive markers in breast cancer.
- MeSH
- buněčné jádro metabolismus MeSH
- duktální karcinom prsu * genetika metabolismus mortalita MeSH
- lidé MeSH
- lobulární karcinom * genetika metabolismus mortalita MeSH
- NAD(P)H dehydrogenasa (chinon) * genetika metabolismus MeSH
- nádory prsu * genetika metabolismus mortalita MeSH
- NF-kappa B * metabolismus MeSH
- proporcionální rizikové modely MeSH
- regresní analýza MeSH
- sekvenční analýza hybridizací s uspořádaným souborem oligonukleotidů MeSH
- stanovení celkové genové exprese MeSH
- Check Tag
- lidé MeSH
- ženské pohlaví MeSH
Although vascular endothelial growth factor (VEGF) receptor 2 (VEGFR2) is traditionally regarded as an endothelial cell protein, evidence suggests that VEGFRs may be expressed by cancer cells. Glioblastoma multiforme (GBM) is a lethal cancer characterized by florid vascularization and aberrantly elevated VEGF. Antiangiogenic therapy with the humanized VEGF antibody bevacizumab reduces GBM tumor growth; however, the clinical benefits are transient and invariably followed by tumor recurrence. In this study, we show that VEGFR2 is preferentially expressed on the cell surface of the CD133(+) human glioma stem-like cells (GSCs), whose viability, self-renewal, and tumorigenicity rely, at least in part, on signaling through the VEGF-VEGFR2-Neuropilin-1 (NRP1) axis. We find that the limited impact of bevacizumab-mediated VEGF blockage may reflect ongoing autocrine signaling through VEGF-VEGFR2-NRP1, which is associated with VEGFR2-NRP1 recycling and a pool of active VEGFR2 within a cytosolic compartment of a subset of human GBM cells. Whereas bevacizumab failed to inhibit prosurvival effects of VEGFR2-mediated signaling, GSC viability under unperturbed or radiation-evoked stress conditions was attenuated by direct inhibition of VEGFR2 tyrosine kinase activity and/or shRNA-mediated knockdown of VEGFR2 or NRP1. We propose that direct inhibition of VEGFR2 kinase may block the highly dynamic VEGF-VEGFR2-NRP1 pathway and inspire a GBM treatment strategy to complement the currently prevalent ligand neutralization approach.
- MeSH
- autokrinní signalizace MeSH
- endozomy fyziologie MeSH
- glioblastom * krevní zásobení patologie patofyziologie terapie MeSH
- humanizované monoklonální protilátky farmakologie MeSH
- lidé MeSH
- malá interferující RNA genetika MeSH
- nádorové kmenové buňky * patologie fyziologie MeSH
- neuropilin-1 * antagonisté a inhibitory genetika fyziologie MeSH
- patologická angiogeneze MeSH
- proliferace buněk MeSH
- vaskulární endoteliální růstový faktor A * antagonisté a inhibitory fyziologie MeSH
- viabilita buněk MeSH
- Check Tag
- lidé MeSH
Tumor biomarkers increasingly provide information for predicting outcomes with chemotherapeutic regimens (personalized medicine). Topo2A is a DNA helicase targeted by anthracyclines, cytotoxic therapeutics used in both adjuvant and palliative treatments of breast cancer. TOP2A gene amplification/deletion is implicated in response to anthracycline-based chemotherapy. We describe an approach for analyzing formalin-fixed, paraffin-embedded breast tumors on tissue microarrays with TOP2A fluorescence in situ hybridization coupled with cytokeratin immunofluorescence to target tumor cells. Stained tissue from patient specimens was imaged and analyzed using Metafer/Metacyte (Metasystems, Waltham, MA, USA), including customized image classifiers. TOP2A/CEN17 ratios of 2.0 or greater (amplified) and 0.8 or less (deleted) were observed for 10.0% and 6.1% of the patients, respectively. Patient outcomes for adjuvant chemotherapy (cyclophosphamide-epirubicin-fluorouracil, cyclophosphamide-methotrexate-fluorouracil, no chemotherapy) were evaluated. No statistical significance was achieved for clinical end points regarding TOP2A status in anthracycline-treated patients. However, patients with TOP2A aberrations receiving methotrexate-based therapy exhibited a significant decrease in 5-year distant disease-free survival and breast cancer-specific overall survival, especially for patients with TOP2A deletions (disease-free survival: hazard ratio, 5.31 [P = .001], and breast cancer-specific overall survival: hazard ratio, 6.45 [P < .001]). No significant differences were seen in patients included in the no-chemotherapy group. Topo2A protein levels were assessed by immunohistochemistry with no correlative statistical relevance to immunofluorescence/fluorescence in situ hybridization-based prognosis for cyclophosphamide-epirubicin-fluorouracil or cyclophosphamide-methotrexate-fluorouracil groups. Interestingly, aberrant (under)expressing patients in the no-chemotherapy group exhibited better 5-year distant disease-free survival (hazard ratio, 0.39; P = .004), trending toward more favorable breast cancer-specific overall survival (hazard ratio, 0.61; P = .11). Our results indicate a strategy by which fluorescence in situ hybridization scoring targeted to cytokeratin-positive tumor cells may provide a tool for added precision and efficiency in TOP2A evaluation from tumor tissue. Copyright 2012 Elsevier Inc. All rights reserved.
- MeSH
- adjuvantní chemoterapie MeSH
- antigeny nádorové * genetika MeSH
- cyklofosfamid terapeutické užití MeSH
- DNA vazebné proteiny * genetika MeSH
- DNA-topoisomerasy typu II * genetika MeSH
- dospělí MeSH
- fluoruracil terapeutické užití MeSH
- hybridizace in situ fluorescenční MeSH
- keratiny * genetika MeSH
- lidé středního věku MeSH
- lidé MeSH
- methotrexát terapeutické užití MeSH
- nádory prsu * farmakoterapie genetika patologie MeSH
- přežití bez známek nemoci MeSH
- protokoly protinádorové kombinované chemoterapie terapeutické užití MeSH
- senioři MeSH
- Check Tag
- dospělí MeSH
- lidé středního věku MeSH
- lidé MeSH
- senioři MeSH
- ženské pohlaví MeSH
Impaired DNA damage response pathways may create vulnerabilities of cancer cells that can be exploited therapeutically. One such selective vulnerability is the sensitivity of BRCA1- or BRCA2-defective tumors (hence defective in DNA repair by homologous recombination, HR) to inhibitors of the poly(ADP-ribose) polymerase-1 (PARP-1), an enzyme critical for repair pathways alternative to HR. While promising, treatment with PARP-1 inhibitors (PARP-1i) faces some hurdles, including (1) acquired resistance, (2) search for other sensitizing, non-BRCA1/2 cancer defects and (3) lack of biomarkers to predict response to PARP-1i. Here we addressed these issues using PARP-1i on 20 human cell lines from carcinomas of the breast, prostate, colon, pancreas and ovary. Aberrations of the Mre11-Rad50-Nbs1 (MRN) complex sensitized cancer cells to PARP-1i, while p53 status was less predictive, even in response to PARP-1i combinations with camptothecin or ionizing radiation. Furthermore, monitoring PARsylation and Rad51 foci formation as surrogate markers for PARP activity and HR, respectively, supported their candidacy for biomarkers of PARP-1i responses. As to resistance mechanisms, we confirmed the role of the multidrug resistance efflux transporters and its reversibility. More importantly, we demonstrated that shRNA lentivirus-mediated depletion of 53BP1 in human BRCA1-mutant breast cancer cells increased their resistance to PARP-1i. Given the preferential loss of 53BP1 in BRCA-defective and triple-negative breast carcinomas, our findings warrant assessment of 53BP1 among candidate predictive biomarkers of response to PARPi. Overall, this study helps characterize genetic and functional determinants of cellular responses to PARP-1i and contributes to the search for biomarkers to exploit PARP inhibitors in cancer therapy.
- MeSH
- chemorezistence * MeSH
- DNA vazebné proteiny genetika metabolismus MeSH
- enzymy opravy DNA genetika metabolismus MeSH
- geny MDR MeSH
- inhibitory enzymů farmakologie MeSH
- intracelulární signální peptidy a proteiny * genetika MeSH
- kamptothecin farmakologie MeSH
- karcinom * farmakoterapie MeSH
- lidé MeSH
- nádorové buněčné linie MeSH
- poškození DNA MeSH
- protein BRCA1 genetika metabolismus MeSH
- protein BRCA2 genetika MeSH
- proteiny buněčného cyklu genetika metabolismus MeSH
- protinádorové látky farmakologie MeSH
- regulace genové exprese u nádorů * MeSH
- záření gama terapeutické užití MeSH
- Check Tag
- lidé MeSH
- ženské pohlaví MeSH
