In the frame of this project, we plan to evaluate importance of genetic and phenotypic markers of oxysterol signaling for endocrine therapy of breast carcinoma. In the long-term perspective, we expect significant socio-economic benefit for both patients and health care system with the use of these markers for prognosis and individualized therapy. This project also aims to elucidate mechanisms of action of validated markers and to determine cost-effective method for their screening. Project will contribute to the solution of several priorities of the Czech Program for Medical Research and Innovation, particularly of the domain 1.3 Cancer (subdomains 1.3.1 tumor biology and 1.3.2 individualization of diagnostics and therapy). Results of the project will be published in impacted scientific journals, presented at specialized scientific meetings, and implemented into whole-life education programs for medical personnel. Scientists, lecturers and physicians in the area of experimental and clinical oncology and patients will be major users of the project results.

Hlavním cílem tohoto projektu je studium genetických a fenotypických markerů oxysterolové signalizace z hlediska jejich významu pro hormonální terapii karcinomu prsu. V případě, že se podaří spojit tyto markery s prognózou pacientů, případně je navrhnout jako nástroje k individualizované terapii lze, delším časovém horizontu, očekávat významný socio-ekonomický přínos pro pacienty i systém zdravotní péče v ČR. Tento projekt má rovněž za cíl odhalit mechanismus působení markerů a navrhnout cenově dostupnou metodiku k jejich sledování. Projekt svým zaměřením přispěje k řešení několika priorit Programu na podporu zdravotnického aplikovaného výzkumu a vývoje, zejména podoblasti 1.3 Nádorová onemocnění a dílčích cílů 1.3.1 Nádorová biologie a 1.3.2 Individualizace diagnostiky a terapie. Výsledky řešení projektu budou publikovány v impaktovaných odborných časopisech, prezentovány na specializovaných vědeckých setkáních a implementovány do programů celoživotního vzdělávání lékařských pracovníků. Hlavními příjemci výsledků budou vědečtí pracovníci, pedagogové, lékaři v onkologii a pacienti.

• MeSH
• hormonální substituční terapie MeSH
• lidé MeSH
• nádorové biomarkery analýza   MeSH
• nádory prsu diagnóza   farmakoterapie   MeSH
• oxysteroly analýza   MeSH
• prognóza MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH

• Konspekt
• Patologie. Klinická medicína
• NLK Obory
• onkologie
• genetika, lékařská genetika
• NLK Publikační typ
• závěrečné zprávy o řešení grantu AZV MZ ČR

Oxysterols are oxidized derivatives of cholesterol, both endogenous and exogenous. They have been implicated in numerous pathologies, including cancer. In addition to their roles in carcinogenesis, proliferation, migration, apoptosis, and multiple signalling pathways, they have been shown to modulate cancer therapy. They are known to affect therapy of hormonally positive breast cancer through modulating oestrogen receptor activity. Oxysterols have also been shown in various in vitro models to influence efficacy of chemotherapeutics, such as doxorubicin, vincristine, cisplatin, 5-fluorouracil, and others. Their effects on the immune system should also be considered in immunotherapy. Selective anti-cancer cytotoxic properties of some oxysterols make them candidates for new therapeutic molecules. Finally, differences in oxysterol levels in blood of cancer patients in different stages or versus healthy controls, and in tumour versus non-tumour tissues, show potential of oxysterols as biomarkers for cancer management and patient stratification for optimization of therapy. LINKED ARTICLES: This article is part of a themed issue on Oxysterols, Lifelong Health and Therapeutics. To view the other articles in this section visit http://onlinelibrary.wiley.com/doi/10.1111/bph.v178.16/issuetoc.

• MeSH
• biologické markery MeSH
• imunitní systém MeSH
• imunoterapie MeSH
• lidé MeSH
• nádory * farmakoterapie   MeSH
• oxysteroly * MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH

BACKGROUND AND OBJECTIVE: Membrane solute carrier transporters play an important role in the transport of a wide spectrum of substrates including anticancer drugs and cancer-related physiological substrates. This study aimed to assess the prognostic relevance of gene expression and genetic variability of selected solute carrier transporters in breast cancer. METHODS: Gene expression was determined by quantitative real-time polymerase chain reaction. All SLC46A1 and SLCO1A2 exons and surrounding non-coding sequences in DNA extracted from the blood of patients with breast cancer (exploratory phase) were analyzed by next-generation sequencing technology. Common variants (minor allele frequency ≥ 5%) with in silico-predicted functional relevance were further analyzed in a large cohort of patients with breast cancer (n = 815) and their prognostic and predictive potential was estimated (validation phase). RESULTS: A gene expression and bioinformatics analysis suggested SLC46A1 and SLCO1A2 to play a putative role in the prognosis of patients with breast cancer. In total, 135 genetic variants (20 novel) were identified in both genes in the exploratory phase. Of these variants, 130 were non-coding, three missense, and two synonymous. One common variant in SLCO1A2 and four variants in SLC46A1 were predicted to be pathogenic by in silico programs and subsequently validated. A SLC46A1 haplotype block composed of rs2239911-rs2239910-rs8079943 was significantly associated with ERBB2/HER2 status and disease-free survival of hormonally treated patients. CONCLUSIONS: This study revealed the prognostic value of a SLC46A1 haplotype block for breast cancer that should be further studied.

• MeSH
• analýza přežití MeSH
• folátový přenašeč spřažený s transportem protonů genetika   MeSH
• genetická variace * MeSH
• haplotypy MeSH
• kvantitativní polymerázová řetězová reakce MeSH
• lidé MeSH
• nádorové biomarkery genetika   MeSH
• nádory prsu genetika   MeSH
• přenašeče organických aniontů genetika   MeSH
• prognóza MeSH
• regulace genové exprese u nádorů MeSH
• sekvenční analýza DNA MeSH
• vysoce účinné nukleotidové sekvenování MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Oxygenated metabolites of cholesterol (oxysterols) have been previously demonstrated to contribute to progression of various cancers and to modulate resistance to breast cancer endocrine therapy in vitro. We measured prognostic roles of circulating levels of seven major oxysterols in the progression of luminal subtype breast carcinoma. Liquid chromatography coupled with tandem mass spectrometry was used for determination of levels of non-esterified 25-hydroxycholesterol, 27-hydroxycholesterol, 7α-hydroxycholesterol, 7-ketocholesterol, cholesterol-5α,6α-epoxide, cholesterol-5β,6β-epoxide, and cholestane-3β,5α,6β-triol in plasma samples collected from patients (n = 58) before surgical removal of tumors. Oxysterol levels were then associated with clinical data of patients. All oxysterols except cholesterol-5α,6α-epoxide were detected in patient plasma samples. Circulating levels of 7α-hydroxycholesterol and 27-hydroxycholesterol were significantly lower in patients with small tumors (pT1) and cholesterol-5β,6β-epoxide and cholestane-3β,5α,6β-triol were lower in patients with stage IA disease compared to larger tumors or more advanced stages. Patients with higher than median cholestane-3β,5α,6β-triol levels had significantly worse disease-free survival than patients with lower levels (p = 0.037 for all patients and p = 0.015 for subgroup treated only with tamoxifen). In conclusion, this study shows, for the first time, that circulating levels of oxysterols, especially cholestane-3β,5α,6β-triol, may have prognostic roles in patients with luminal subtype breast cancer.

• MeSH
• duktální karcinom prsu krev   patologie   MeSH
• invazivní růst nádoru MeSH
• lidé středního věku MeSH
• lidé MeSH
• míra přežití MeSH
• nádorové biomarkery analýza   MeSH
• nádory prsu krev   patologie   MeSH
• následné studie MeSH
• oxysteroly krev   MeSH
• prognóza MeSH
• receptor erbB-2 metabolismus   MeSH
• receptory pro estrogeny metabolismus   MeSH
• receptory progesteronu metabolismus   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH

Breast cancer is the most common cancer in women in the world. The role of germline genetic variability in ATP-binding cassette (ABC) transporters in cancer chemoresistance and prognosis still needs to be elucidated. We used next-generation sequencing to assess associations of germline variants in coding and regulatory sequences of all human ABC genes with response of the patients to the neoadjuvant cytotoxic chemotherapy and disease-free survival (n = 105). A total of 43 prioritized variants associating with response or survival in the above testing phase were then analyzed by allelic discrimination in the large validation set (n = 802). Variants in ABCA4, ABCA9, ABCA12, ABCB5, ABCC5, ABCC8, ABCC11, and ABCD4 associated with response and variants in ABCA7, ABCA13, ABCC4, and ABCG8 with survival of the patients. No association passed a false discovery rate test, however, the rs17822931 (Gly180Arg) in ABCC11, associating with response, and the synonymous rs17548783 in ABCA13 (survival) have a strong support in the literature and are, thus, interesting for further research. Although replicated associations have not reached robust statistical significance, the role of ABC transporters in breast cancer should not be ruled out. Future research and careful validation of findings will be essential for assessment of genetic variation which was not in the focus of this study, e.g., non-coding sequences, copy numbers, and structural variations together with somatic mutations.

• MeSH
• ABC transportéry genetika   MeSH
• alely MeSH
• frekvence genu MeSH
• genetická variace * MeSH
• genotyp MeSH
• jednonukleotidový polymorfismus MeSH
• Kaplanův-Meierův odhad MeSH
• lidé MeSH
• lokus kvantitativního znaku MeSH
• nádorové biomarkery * MeSH
• nádory prsu diagnóza   genetika   mortalita   terapie   MeSH
• neoadjuvantní terapie MeSH
• prognóza MeSH
• protokoly antitumorózní kombinované chemoterapie terapeutické užití   MeSH
• výsledek terapie MeSH
• vysoce účinné nukleotidové sekvenování MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Breast cancer patients with high cholesterol biosynthesis signature had poorer therapeutic outcome. Cytochrome P450 (CYP) 2D6 is crucial in the oxidation of tamoxifen to generate active metabolites, 4-hydroxytamoxifen and endoxifen. CYP2D6 variants with C100T substitution encode null or poor functional proteins. This study aims to examine the association of C100T genotypes and serum lipid levels with plasma drug levels in patients. Plasma tamoxifen concentration was positively associated with serum triglyceride concentration, adjusting for age and C100T genotype. Overweight (body mass index >24.0) patients with high serum cholesterol (≥200 mg/dL) had increased risks of ineffective endoxifen levels (<5.97 ng/mL). Compared to the low-cholesterol group, the high-cholesterol group had a lower 4-hydroxytamoxifen or endoxifen level in T/T carriers. In T/T carriers, the high-cholesterol group had an increased risk of an ineffective endoxifen level. Metastasis, hot flash/flushing, and high alanine transaminase did not relate to plasma 4-hydroxytamoxifen or endoxifen levels. Results indicate that C100T and high serum cholesterol are risk factors of ineffective endoxifen levels in Taiwanese breast cancer patients. These findings warrant further studies of a large hypercholesterolemic population to examine the outcome of increased doses of tamoxifen.

• MeSH
• antitumorózní látky hormonální krev   MeSH
• cholesterol krev   MeSH
• cytochrom P-450 CYP2D6 metabolismus   MeSH
• dospělí MeSH
• fenotyp MeSH
• genotyp MeSH
• lidé středního věku MeSH
• lidé MeSH
• nádory prsu krev   metabolismus   MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• tamoxifen analogy a deriváty   krev   MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• senioři nad 80 let MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Multidrug resistance to anticancer drugs, which is often associated with enhanced expression of the ATP‑binding cassette (ABC) transporter P‑glycoprotein (encoded by the ABCB1 gene) may limit the effects of cancer therapy. Epigenetic regulation of ABCB1 expression may thus have a clinical impact. A detailed assessment of ABCB1 promoter methylation is of importance for predicting therapy outcome and prognosis. Thus, validated methods for the analysis of ABCB1 promoter methylation are urgently required. In the present study, high‑resolution melting (HRM) analysis of the CpG island regions covering the distal promoter of the ABCB1 gene was developed and compared with pyrosequencing. In addition, the clinical effects of the methylation status of the ABCB1 promoter were analyzed in patients with breast and ovarian carcinoma prior and subsequent to chemotherapy treatment. HRM analysis of ABCB1 methylation correlated with the results of pyrosequencing (P=0.001) demonstrating its analytical validity and utility. Hypermethylation of the analyzed ABCB1 promoter region was significantly correlated with low levels of the ABCB1 transcript in tumors from a subset of patients with breast and ovarian carcinoma prior to chemotherapy but not following treatment. Finally, high ABCB1 transcript levels were observed in tumors of patients with short progression‑free survival prior to chemotherapy. Our data suggest the existence of functional epigenetic changes in the ABCB1 gene with prognostic value in tumor tissues of patients with breast and ovarian carcinoma. The clinical importance of such changes should be further evaluated.

• MeSH
• denaturace nukleových kyselin MeSH
• duktální karcinom prsu farmakoterapie   genetika   patologie   MeSH
• epigeneze genetická MeSH
• invazivní růst nádoru MeSH
• lidé MeSH
• metylace DNA * MeSH
• míra přežití MeSH
• nádorové biomarkery genetika   MeSH
• nádory prsu farmakoterapie   genetika   patologie   MeSH
• nádory vaječníků farmakoterapie   genetika   patologie   MeSH
• následné studie MeSH
• P-glykoproteiny genetika   MeSH
• polymerázová řetězová reakce metody   MeSH
• prognóza MeSH
• promotorové oblasti (genetika) * MeSH
• regulace genové exprese u nádorů MeSH
• retrospektivní studie MeSH
• serózní cystadenokarcinom farmakoterapie   genetika   patologie   MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Cardiotoxicity is a serious adverse reaction to cancer chemotherapy and may lead to critical heart damage. Imatinib mesylate (IMB), a selective tyrosine kinase inhibitor, is sometimes accompanied by severe cardiovascular complications. To minimize risk, early biomarkers of such complications are of utmost importance. At the present time, microRNAs (miRNAs) are intensively studied as potential biomarkers of many pathological processes. Many miRNAs appear to be specific in some tissues, including the heart. In the present study we have explored the potential of specific miRNAs to be early markers of IMB-induced cardiotoxicity. Doxorubicin (DOX), an anthracycline with well-known cardiotoxicity, was used for comparison. NMRI mice were treated with IMB or DOX for nine days in doses corresponding to the highest recommended doses in oncological patients, following which plasmatic levels of miRNAs were analyzed in miRNA microarrays and selected cardio-specific miRNAs were quantified using qPCR. The plasmatic level of miR-1a, miR-133a, miR-133b, miR-339, miR-7058, miR-6236 and miR-6240 were the most different between the IMB-treated and control mice. Interestingly, most of the miRNAs affected by DOX were also affected by IMB showing the same trends. Concerning selected microRNAs in the hearts of individual mice, only miR-34a was significantly increased after DOX treatment, and only miR-205 was significantly decreased after IMB and DOX treatment. However, no changes in any miRNA expression correlated with the level of troponin T, a classical marker of heart injury.

• MeSH
• doxorubicin toxicita   MeSH
• imatinib mesylát farmakologie   MeSH
• mikro RNA krev   genetika   metabolismus   MeSH
• myši MeSH
• regulace genové exprese účinky léků   MeSH
• srdce účinky léků   MeSH
• transkriptom účinky léků   MeSH
• troponin T krev   genetika   metabolismus   MeSH
• zvířata MeSH
• Check Tag
• myši MeSH
• ženské pohlaví MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH

Single nucleotide polymorphisms located in 5' untranslated regions (5'UTRs) can regulate gene expression and have clinical impact. Recognition of functionally significant sequences within 5'UTRs is crucial in next-generation sequencing applications. Furthermore, information about the behavior of 5'UTRs during gene evolution is scarce. Using the example of the ATP-binding cassette transporter A1 (ABCA1) gene (Tangier disease), we describe our algorithm for functionally significant sequence finding. 5'UTR features (upstream start and stop codons, open reading frames (ORFs), GC content, motifs, and secondary structures) were studied using freely available bioinformatics tools in 55 vertebrate orthologous genes obtained from Ensembl and UCSC. The most conserved sequences were suggested as hot spots. Exon and intron enhancers and silencers (sc35, ighg2 cgamma2, ctnt, gh-1, and fibronectin eda exon), transcription factors (TFIIA, TATA, NFAT1, NFAT4, and HOXA13), some of them cancer related, and microRNA (hsa-miR-4474-3p) were localized to these regions. An upstream ORF, overlapping with the main ORF in primates and possibly coding for a small bioactive peptide, was also detected. Moreover, we showed several features of 5'UTRs, such as GC content variation, hairpin structure conservation or 5'UTR segmentation, which are interesting from a phylogenetic point of view and can stimulate further evolutionary oriented research.

• MeSH
• 5' nepřekládaná oblast * genetika   MeSH
• ABCA1 protein chemie   genetika   MeSH
• anotace sekvence MeSH
• fylogeneze MeSH
• introny MeSH
• konformace nukleové kyseliny MeSH
• konzervovaná sekvence genetika   MeSH
• lidé MeSH
• messenger RNA genetika   metabolismus   MeSH
• nukleotidové motivy genetika   MeSH
• otevřené čtecí rámce genetika   MeSH
• savci genetika   MeSH
• sekvence aminokyselin MeSH
• sekvence nukleotidů MeSH
• sestřih RNA genetika   MeSH
• zastoupení bazí genetika   MeSH
• zesilovače transkripce genetika   MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH

INTRODUCTION: Ovarian cancer (OC) represents a serious disease with high mortality and lack of efficient predictive and prognostic biomarkers. ATP-binding cassette (ABC) proteins constitute a large family dedicated to active transmembrane transport including transport of xenobiotics. MATERIALS AND METHODS: mRNA level was measured by quantitative RT-PCR in tumor tissues from OC patients. Bioinformatics analyses were applied to two gene expression datasets (60 primary tumors and 29 peritoneal metastases). Two different approaches of expression data normalization were applied in parallel, and their results were compared. Data from publically available cancer datasets were checked to further validate our conclusions. RESULTS: The results showed significant connections between ABC gene expression profiles and time to progression (TTP), chemotherapy resistance, and metastatic progression in OC. Two consensus ABC gene profiles with clinical meaning were documented. (a) Downregulation of ABCC4, ABCC10, ABCD3, ABCE1, ABCF1, ABCF2, and ABCF3 was connected with the best sensitivity to chemotherapy and TTP. (b) Oppositely, downregulation of ABCB11 and upregulation of ABCB1 and ABCG2 were connected with the worst sensitivity to chemotherapy and TTP. Results from publicly available online databases supported our conclusions. CONCLUSION: This study stressed the connection between two well-documented ABC genes and clinicopathological features-ABCB1 and ABCG2. Moreover, we showed a comparable connection also for several other ABC genes-ABCB11, ABCC4, ABCC10, ABCD3, ABCE1, ABCF1, ABCF2, and ABCF3. Our results add new clinically relevant information to this oncology field and can stimulate further exploration.

• MeSH
• ABC transportéry genetika   MeSH
• chemorezistence genetika   MeSH
• lidé MeSH
• messenger RNA genetika   MeSH
• nádory vaječníků genetika   patologie   MeSH
• peritoneální nádory genetika   sekundární   MeSH
• regulace genové exprese u nádorů * MeSH
• transkriptom MeSH
• výpočetní biologie MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH