Validation of differences in expression of previously identified genetic markers between patients with breast carcinoma treated by standard, mainly neoadjuvant chemotherapy, will be the main goal of this project. Markers representing metabolism (e.g. cytochromes P450, SOD, NQO) and transport (ABC and SLC transporters) of anticancer drugs will be studied in relation to clinico-pathological characteristics, therapy outcome and survival of patients. Mechanism of action of validated markers will be studied by correlation of gene expression with protein level and analysis of genotype. Methylation of regulatory elements of candidate genes will be studied as independent prognostic or predictive marker. Special attention will be paid to the study of aggressive triple-negative tumors in both patients and cell models. Breast tumor cell line models differing in expression of receptors (estrogen, progesterone, ERBB2) will be employed for elucidation of mechanisms of action of biomarkers by alternative approach.

Hlavním záměrem projektu je validace a studium mechanismu účinku námi nedávno odhalených genetických markerů, tj. genové exprese v nádorových tkáních a genových polymorfismů v krvi pacientů léčených standardní, především neoadjuvantní chemoterapií karcinomu prsu. Cílem jsou markery metabolismu (např.: cytochromy P450, NQO, SOD, dráha 5-fluorouracilu) a transportu (ABC a SLC transportéry) cytostatik ve vztahu ke klinicko-patologickým charakteristikám, přežívání a účinnosti léčby pacientek. U úspěšně validovaných kandidátů budeme studovat mechanismus jakým markery působí korelací genové exprese s hladinou proteinu a zjištěním významu genotypu. Budeme studovat i methylaci regulačních oblastí kandidátních genů jako nezávislý marker. Zvláštní pozornost budeme věnovat studiu agresivních triple-negative karcinomů u pacientů i na modelových buněčných liniích s tímto fenotypem. U buněčných modelů se pokusíme vysledovat mechanismus nezávislou cestou včetně hledání vztahu mezi typem léčiva, jeho dávkou a účinkem

• MeSH
• ABC transportéry analýza   MeSH
• analýza přežití MeSH
• cytostatické látky MeSH
• exprese genu MeSH
• metylace MeSH
• nádorové biomarkery analýza   MeSH
• nádory prsu farmakoterapie   genetika   MeSH
• neoadjuvantní terapie MeSH
• polymorfismus genetický MeSH
• systém (enzymů) cytochromů P-450 analýza   MeSH
• triple-negativní karcinom prsu farmakoterapie   genetika   MeSH
• vztah mezi dávkou a účinkem léčiva MeSH

• Konspekt
• Biochemie. Molekulární biologie. Biofyzika
• NLK Obory
• genetika, lékařská genetika
• biologie
• farmacie a farmakologie
• onkologie
• NLK Publikační typ
• závěrečné zprávy o řešení grantu IGA MZ ČR

AIM: A role of caspase-2 in chemotherapy-induced apoptosis has been suggested. Our study aimed to evaluate the prognostic and predictive importance of caspase-2 isoforms in breast cancer patients. MATERIALS & METHODS: Caspase-2L and -2S transcript levels were determined in paired tumor and non-malignant control tissues from 64 patients after neoadjuvant chemotherapy and 100 pretreatment patients (general set) by real-time PCR with absolute quantification. RESULTS: Low but statistically significant upregulation of caspase-2L in tumor versus control tissues was observed in both sets. Significant associations of the levels of caspase-2L, -2S or S/L ratio with clinical prognostic factors were observed. However, none of these associations were confirmed in both sets. Levels of caspase-2 isoforms or the S/L ratio did not significantly associate with progression-free survival in the general set or with chemotherapy response in the neoadjuvant set. CONCLUSION: Our results suggest that the role of caspase-2 isoforms in the progression of breast cancer may considerably differ between pre- and post-chemotherapy patients.

• MeSH
• adjuvantní chemoterapie MeSH
• cysteinové endopeptidasy genetika   metabolismus   MeSH
• dospělí MeSH
• duktální karcinom prsu enzymologie   mortalita   MeSH
• frekvence genu MeSH
• izoenzymy genetika   metabolismus   MeSH
• Kaplanův-Meierův odhad MeSH
• kaspasa 2 genetika   metabolismus   MeSH
• lidé středního věku MeSH
• lidé MeSH
• messenger RNA genetika   metabolismus   MeSH
• nádory prsu enzymologie   mortalita   MeSH
• neoadjuvantní terapie MeSH
• sekvenční analýza DNA MeSH
• senioři MeSH
• upregulace MeSH
• Check Tag
• dospělí MeSH
• lidé středního věku MeSH
• lidé MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

ATP-binding cassette (ABC) transporters, belonging to the family D, are expressed in peroxisomes, endoplasmic reticulum or lysosomes. ABCD transporters play a role in transport of lipids, bile acids and vitamin B12 and associate with peroxisomal disorders. ABCD1 performs transport of coenzyme A esters of very-long-chain fatty acids (VLCFA) in peroxisomes and a number of mutations in ABCD1 gene were linked to an X-linked adrenoleucodystrophy (X-ALD). The role of ABCD transporters in tumour growth has not been studied in detail, but there is some evidence that ABCDs levels differ between undifferentiated stem or tumour cells and differentiated cells suggesting a possible link to tumorigenesis. In this mini-review, we discuss the available information about the role of ABCD transporters in cancer.

• MeSH
• ABC transportéry genetika   metabolismus   MeSH
• adrenoleukodystrofie genetika   metabolismus   MeSH
• lidé MeSH
• mastné kyseliny metabolismus   MeSH
• multigenová rodina genetika   MeSH
• mutace MeSH
• nádory genetika   metabolismus   patologie   MeSH
• peroxizomy metabolismus   MeSH
• progrese nemoci MeSH
• regulace genové exprese u nádorů MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• přehledy MeSH

AIM: ATP-binding cassette (ABC) transporters contribute to development of resistance to anticancer drugs via ATP-dependent drug efflux. A major goal of our study was to investigate associations between the expression of ABC transporters and outcome of breast carcinoma patients. PATIENTS & METHODS: Transcript levels of all 49 human ABC transporters were determined in post-treatment tumor and non-neoplastic tissue samples from 68 breast carcinoma patients treated by neoadjuvant chemotherapy. Six ABC transporters were then evaluated in independent series of 100 pretreatment patients. RESULTS: ABCA5/6/8/9/10, ABCB1/5/11, ABCC6/9, ABCD2/4, ABCG5 and ABCG8 were significantly downregulated and ABCA2/3/7/12, ABCB2/3/8/9/10, ABCC1/4/5/10/11/12, ABCD1/3, ABCE1, ABCF1/2/3 and ABCG1 were upregulated in post-treatment tumors compared with non-neoplastic tissues. Significant associations of intratumoral levels of ABCC1 and ABCC8 with grade and expression of hormonal receptors were found in both sets of patients. ABCA12, ABCA13 and ABCD2 levels were significantly associated with the response to neoadjuvant chemotherapy in post-treatment patients. Protein expression of ABCA12, ABCC8 and ABCD2 in tumor tissues of patients with breast carcinoma was observed by immunoblotting for the first time. CONCLUSION: ABCA12, ABCA13, ABCC1, ABCC8 and ABCD2 present potential modifiers of progression and response to the chemotherapy of breast carcinoma.

• MeSH
• ABC transportéry genetika   metabolismus   MeSH
• antitumorózní látky aplikace a dávkování   MeSH
• genetické asociační studie MeSH
• karcinom farmakoterapie   genetika   patologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• nádory prsu farmakoterapie   genetika   patologie   MeSH
• neoadjuvantní terapie MeSH
• regulace genové exprese u nádorů MeSH
• stanovení celkové genové exprese MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

Resistance of cancer cells to chemotherapeutic agents is one of the main causes of treatment failure. In order to detect proteins potentially involved in the mechanism of resistance to taxanes, we assessed differences in protein expression in MCF-7 breast cancer cells that are sensitive to paclitaxel and in the same cells with acquired resistance to paclitaxel (established in our lab). Proteins were separated using two-dimensional electrophoresis. Changes in their expression were determined and proteins with altered expression were identified using mass spectrometry. Changes in their expression were confirmed using western blot analysis. With these techniques, we found three proteins expressed differently in resistant MCF-7 cells, i.e., thyroid hormone-interacting protein 6 (TRIP6; upregulated to 650%), heat shock protein 27 (HSP27; downregulated to 50%) and cathepsin D (downregulated to 28%). Silencing of TRIP6 expression by specific siRNA leads to decreased number of grown resistant MCF-7 cells. In the present study we have pointed at some new directions in the studies of the mechanism of resistance to paclitaxel in breast cancer cells.

• MeSH
• adaptorové proteiny signální transdukční metabolismus   MeSH
• antitumorózní látky fytogenní farmakologie   MeSH
• chemorezistence MeSH
• kathepsin D metabolismus   MeSH
• lidé MeSH
• MFC-7 buňky MeSH
• nádory prsu MeSH
• paclitaxel farmakologie   MeSH
• proteiny s doménou LIM metabolismus   MeSH
• proteiny tepelného šoku HSP27 metabolismus   MeSH
• proteom metabolismus   MeSH
• transkripční faktory metabolismus   MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

OBJECTIVES: ATP-Binding Cassette (ABC) transporters may cause treatment failure by transporting of anticancer drugs outside of the tumor cells. Multidrug resistance-associated protein 1 coded by the ABCC1 gene has recently been suggested as a potential prognostic marker in breast cancer patients. This study aimed to explore tagged haplotype covering nucleotide binding domain 1 of ABCC1 in relation with corresponding transcript levels in tissues and clinical phenotype of breast cancer patients. METHODS: The distribution of twelve ABCC1 polymorphisms was assessed by direct sequencing in peripheral blood DNA (n = 540). RESULTS: Tumors from carriers of the wild type genotype in rs35623 or rs35628 exhibited significantly lower levels of ABCC1 transcript than those from carriers of the minor allele (p = 0.003 and p = 0.004, respectively). The ABCC1 transcript levels significantly increased in the order CT-GT>CC-GT>CC-GG for the predicted rs35626-rs4148351 diplotype. Chemotherapy-treated patients carrying the T allele in rs4148353 had longer disease-free survival than those with the GG genotype (p = 0.043). On the other hand, hormonal therapy-treated patients with the AA genotype in rs35628 had significantly longer disease-free survival than carriers of the G allele (p = 0.012). CONCLUSIONS: Taken together, our study shows that genetic variability in the nucleotide binding domain 1 has a significant impact on the ABCC1 transcript level in the target tissue and may modify survival of breast cancer patients.

• MeSH
• analýza přežití * MeSH
• jednonukleotidový polymorfismus * MeSH
• lidé středního věku MeSH
• lidé MeSH
• messenger RNA genetika   MeSH
• nádory prsu genetika   patofyziologie   MeSH
• proteiny spojené s mnohočetnou rezistencí k lékům genetika   metabolismus   MeSH
• senioři MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH

The resistance of cancer cells to chemotherapeutic drugs represents a major problem in cancer treatment. Despite all efforts, mechanisms of resistance have not yet been elucidated. To reveal proteins that could be involved in resistance to taxanes, we compared protein expression in whole cell lysates of SK-BR-3 breast cancer cells sensitive to paclitaxel and in lysates of the same line with acquired resistance to paclitaxel. The resistant SK-BR-3 cell line was established in our lab. Protein separation was achieved using high-resolution 2D-electrophoresis, computer analysis and mass spectro-metry. With these techniques we identified four proteins with different expression in resistant SK-BR-3 cells, i.e., serpin B3, serpin B4, heat shock protein 27 (all three upregulated) and cytokeratin 18 (downregulated). Observed changes were confirmed using western blot analysis. This study suggests new directions worthy of further study in the effort to reveal the mechanism of resistance to paclitaxel in breast cancer cells.

• MeSH
• 2D gelová elektroforéza MeSH
• adenokarcinom metabolismus   MeSH
• antigeny nádorové biosyntéza   MeSH
• antitumorózní látky fytogenní farmakologie   MeSH
• chemorezistence fyziologie   MeSH
• keratin-18 biosyntéza   MeSH
• lidé MeSH
• nádorové buněčné linie MeSH
• nádory prsu metabolismus   MeSH
• paclitaxel farmakologie   MeSH
• proteiny tepelného šoku HSP27 biosyntéza   MeSH
• proteomika MeSH
• serpiny biosyntéza   MeSH
• spektrometrie hmotnostní - ionizace laserem za účasti matrice MeSH
• western blotting MeSH
• Check Tag
• lidé MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH