Chemoresistance represents a major issue affecting cancer therapy efficacy. Because microRNAs (miRNAs) regulate gene expression on multiple levels, their role in chemoresistance development is reasonably certain. In our previous study, miR-122-5p and miR-142-5p were identified as diagnostic, prognostic, and predictive biomarkers for primary and metastatic rectal cancer. The aim of the present study was to investigate whether these miRNAs can also reflect the disease course of patients with colon cancer (CC). Further, we focused on a deeper understanding of their involvement in 5-fluorouracil (5-FU) chemoresistance development.

• MeSH
• chemorezistence * genetika   MeSH
• fluoruracil * terapeutické užití   farmakologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mikro RNA * genetika   krev   MeSH
• nádorové biomarkery genetika   krev   MeSH
• nádory tračníku * genetika   farmakoterapie   krev   patologie   MeSH
• prognóza MeSH
• regulace genové exprese u nádorů MeSH
• senioři MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

The diagnostic performance of molecular markers in surrogate tissues like stool may be affected by colorectal cancer (CRC) morphological heterogeneity. The mucinous histotype represents a subgroup of CRC with a peculiar molecular program and unfavorable disease progression. However, the percentage of mucinous morphology necessary to define this subtype is still a matter of debate. In this study, we investigated whether stool miRNA profiles of CRC patients differ in patients with mucinous histopathological subtypes compared to non-mucinous cancers. In this respect, we also explored how the stool miRNA signature reported in our previous multicentric study behaves in this histotype. Small-RNA sequencing was performed in fecal and tissue samples of an Italian cohort (n = 172), including 27 CRC with mucinous morphology (mucinous cancers with ≥ 50% mucinous morphology and those with mucinous component ≥ 5% but < 50%), 58 non-mucinous CRC, and 87 colonoscopy-negative controls. Results were compared with fecal miRNA profiles of a cohort from the Czech Republic (n = 98). Most of the differentially expressed (DE) stool miRNAs (n = 324) were in common between CRC with mucinous morphology and non-mucinous histopathological subtypes in comparison with healthy controls. Interestingly, the altered levels of 25 fecal miRNAs previously identified distinguishing CRC cases from controls in both cohorts were also confirmed after stratification for mucinous morphology. Forty-nine miRNAs were DE exclusively in CRC with mucinous morphology and 61 in non-mucinous CRC. Mucinous cancers and those with mucinous component showed fairly similar profiles that were comparable in the Czech cohort. Among the stool DE miRNAs observed in CRC with mucinous morphology, 20 were also altered in the comparison between tumor and adjacent mucosa tissue. This study highlights miRNAs specifically altered in CRC with mucinous morphology. Nevertheless, the performance of our stool miRNA signature in accurately distinguishing CRC cases from controls was not significantly affected by this histological subtype. This aspect further supports the use of stool miRNAs for noninvasive diagnosis and screening strategies.

• MeSH
• feces * chemie   MeSH
• kohortové studie MeSH
• kolorektální nádory * genetika   patologie   MeSH
• lidé středního věku MeSH
• lidé MeSH
• mikro RNA * genetika   metabolismus   MeSH
• mucinózní adenokarcinom * genetika   patologie   MeSH
• nádorové biomarkery genetika   MeSH
• regulace genové exprese u nádorů MeSH
• senioři MeSH
• stanovení celkové genové exprese metody   MeSH
• Check Tag
• lidé středního věku MeSH
• lidé MeSH
• mužské pohlaví MeSH
• senioři MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH

Selekce během metastázování vede k posunu molekulárních profilů u jaterních metastáz kolorektálního karcinomu (CRLM) v porovnáni s primárním karcinomem tlustého střeva (CRC). CRC, které pocházejí z levé strany tlustého střeva, vykazují odlišné molekulární vlastnosti a prognózu a měli by být léčeni odlišně než pacienti s CRC pocházející z pravé strany. Genomové změny v solidních nádorech mohou umožnit prostřednictvím simultánního sekvenování DNA a RNA izolované z primárních a metastatických CRC sledování reakce pacienta na terapii. Hlavním cílem je identifikovat mutace spojené s předpovědí na léčbu. Získané výsledky budou porovnávany mezi CRC pacienty s dobrou a špatnou odpovědí na chemoterapii u pacientů s nádorem v levé nebo pravé části tlustého střeva. Přítomnost mutací bude nezávisle ověřena na větším počtu pacientů s CRC z České republiky i celosvětových konsorcií zaměřených na výzkum CRC. Význam projektu spočívá v zlepšení účinnosti léčby u pacientů s CRC.; Selection during metastasizing may shift molecular patterns by which colorectal cancer liver metastases retain their unique molecular profile. Colorectal tumors originating from the left side of colon harbor distinct molecular properties and prognosis and consequently should be treated differently from those in the right side. Genomic alterations in solid cancers can be characterized by next generation sequencing of DNA and RNA to monitor patient’s reaction to therapy. We aim to monitor genomic evolution of cancer in relation to the specific therapy by a whole exome and transcriptome sequencing of primary and metastatic colon cancer patients. The main aim is to identify mutations associated with therapy outcome. We will compare obtained outcomes between good and poor responders to chemotherapy originating from left- or right-side of CRC. The presence of mutations will be independently validated on a larger set of patients from both Czech Republic and Colorectal Consortia. The significance of the project lays on improvement of the therapy efficacy in colon cancer patients.

• Klíčová slova
• rezistence, resistance, Metastasis, targeted therapy, cílená léčba, chemoterapie, chemotherapy, metastáza, colon cancer, karcinom střeva, specifická mutace, imunologický přístup, specific mutation, immunological approach,

• NLK Publikační typ
• závěrečné zprávy o řešení grantu AZV MZ ČR

Genome-wide association studies (GWAS) have identified more than 200 common genetic variants independently associated with colorectal cancer (CRC) risk, but the causal variants and target genes are mostly unknown. We sought to fine-map all known CRC risk loci using GWAS data from 100,204 cases and 154,587 controls of East Asian and European ancestry. Our stepwise conditional analyses revealed 238 independent association signals of CRC risk, each with a set of credible causal variants (CCVs), of which 28 signals had a single CCV. Our cis-eQTL/mQTL and colocalization analyses using colorectal tissue-specific transcriptome and methylome data separately from 1299 and 321 individuals, along with functional genomic investigation, uncovered 136 putative CRC susceptibility genes, including 56 genes not previously reported. Analyses of single-cell RNA-seq data from colorectal tissues revealed 17 putative CRC susceptibility genes with distinct expression patterns in specific cell types. Analyses of whole exome sequencing data provided additional support for several target genes identified in this study as CRC susceptibility genes. Enrichment analyses of the 136 genes uncover pathways not previously linked to CRC risk. Our study substantially expanded association signals for CRC and provided additional insight into the biological mechanisms underlying CRC development.

• MeSH
• Asijci * genetika   MeSH
• běloši * genetika   MeSH
• celogenomová asociační studie * MeSH
• genetická predispozice k nemoci * MeSH
• jednonukleotidový polymorfismus * MeSH
• kolorektální nádory * genetika   MeSH
• lidé MeSH
• lokus kvantitativního znaku * MeSH
• mapování chromozomů MeSH
• sekvenování exomu MeSH
• studie případů a kontrol MeSH
• transkriptom MeSH
• východní Asiaté MeSH
• Check Tag
• lidé MeSH
• mužské pohlaví MeSH
• ženské pohlaví MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH

• Publikační typ
• abstrakt z konference MeSH

MUC13, a transmembrane mucin glycoprotein, is overexpressed in colorectal cancer (CRC), however, its regulation and functions are not fully understood. It has been shown that MUC13 protects colonic epithelial cells from apoptosis. Therefore, studying MUC13 and MUC13-regulated pathways may reveal promising therapeutic approaches for CRC treatment. Growing evidence suggests that microRNAs (miRs) are involved in the development and progression of CRC. In the present study, the MUC13-miR-4647 axis was addressed in association with survival of patients. miR-4647 is predicted in silico to bind to the MUC13 gene and was analyzed by RT-qPCR in 187 tumors and their adjacent non-malignant mucosa of patients with CRC. The impact of previously mentioned genes on survival and migration abilities of cancer cells was validated in vitro. Significantly upregulated MUC13 (P=0.02) in was observed tumor tissues compared with non-malignant adjacent mucosa, while miR-4647 (P=0.05) showed an opposite trend. Higher expression levels of MUC13 (log-rank P=0.05) were associated with worse patient's survival. The ectopic overexpression of studied miR resulted in decreased migratory abilities and worse survival of cells. Attenuated MUC13 expression levels confirmed the suppression of colony forming of CRC cells. In summary, the present data suggested the essential role of MUC13-miR-4647 in patients' survival, and this axis may serve as a novel therapeutic target. It is anticipated MUC13 may hold significant potential in the screening, diagnosis and treatment of CRC.

• Publikační typ
• časopisecké články MeSH

Colorectal cancer (CRC) is a leading cause of mortality worldwide. We conducted a genome-wide association study meta-analysis of 100,204 CRC cases and 154,587 controls of European and east Asian ancestry, identifying 205 independent risk associations, of which 50 were unreported. We performed integrative genomic, transcriptomic and methylomic analyses across large bowel mucosa and other tissues. Transcriptome- and methylome-wide association studies revealed an additional 53 risk associations. We identified 155 high-confidence effector genes functionally linked to CRC risk, many of which had no previously established role in CRC. These have multiple different functions and specifically indicate that variation in normal colorectal homeostasis, proliferation, cell adhesion, migration, immunity and microbial interactions determines CRC risk. Crosstissue analyses indicated that over a third of effector genes most probably act outside the colonic mucosa. Our findings provide insights into colorectal oncogenesis and highlight potential targets across tissues for new CRC treatment and chemoprevention strategies.

• MeSH
• celogenomová asociační studie MeSH
• Evropané * genetika   MeSH
• genetická predispozice k nemoci MeSH
• jednonukleotidový polymorfismus genetika   MeSH
• kolorektální nádory * genetika   MeSH
• lidé MeSH
• multiomika MeSH
• východní Asiaté * genetika   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• metaanalýza MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH

In the present review we addressed the determination of DNA damage induced by small-molecule carcinogens, considered their persistence in DNA and mutagenicity in in vitro and in vivo systems over a period of 30 years. The review spans from the investigation of the role of DNA damage in the cascade of chemical carcinogenesis. In the nineties, this concept evolved into the biomonitoring studies comprising multiple biomarkers that not only reflected DNA/chromosomal damage, but also the potential of the organism for biotransformation/elimination of various xenobiotics. Since first years of the new millennium, dynamic system of DNA repair and host susceptibility factors started to appear in studies and a considerable knowledge has been accumulated on carcinogens and their role in carcinogenesis. It was understood that the final biological links bridging the arising DNA damage and cancer onset remain to be elucidated. In further years the community of scientists learnt that cancer is a multifactorial disease evolving over several decades of individual ́s life. Moreover, DNA damage and DNA repair are inseparable players also in treatment of malignant diseases, but affect substantially other processes, such as degeneration. Functional monitoring of DNA repair pathways and DNA damage response may cast some light on above aspects. Very little is currently known about the relationship between telomere homeostasis and DNA damage formation and repair. DNA damage/repair in genomic and mitochondrial DNA and crosstalk between these two entities emerge as a new interesting topic.

• MeSH
• DNA MeSH
• karcinogeneze genetika   MeSH
• karcinogeny MeSH
• kometový test MeSH
• lidé MeSH
• oprava DNA MeSH
• poškození DNA MeSH
• pracovní expozice * MeSH
• xenobiotika * toxicita   MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• přehledy MeSH

Polygenic risk scores (PRS) have great potential to guide precision colorectal cancer (CRC) prevention by identifying those at higher risk to undertake targeted screening. However, current PRS using European ancestry data have sub-optimal performance in non-European ancestry populations, limiting their utility among these populations. Towards addressing this deficiency, we expand PRS development for CRC by incorporating Asian ancestry data (21,731 cases; 47,444 controls) into European ancestry training datasets (78,473 cases; 107,143 controls). The AUC estimates (95% CI) of PRS are 0.63(0.62-0.64), 0.59(0.57-0.61), 0.62(0.60-0.63), and 0.65(0.63-0.66) in independent datasets including 1681-3651 cases and 8696-115,105 controls of Asian, Black/African American, Latinx/Hispanic, and non-Hispanic White, respectively. They are significantly better than the European-centric PRS in all four major US racial and ethnic groups (p-values < 0.05). Further inclusion of non-European ancestry populations, especially Black/African American and Latinx/Hispanic, is needed to improve the risk prediction and enhance equity in applying PRS in clinical practice.

• MeSH
• celogenomová asociační studie MeSH
• etnicita * genetika   MeSH
• genetická predispozice k nemoci MeSH
• jednonukleotidový polymorfismus MeSH
• kolorektální nádory * diagnóza   genetika   MeSH
• lidé MeSH
• multifaktoriální dědičnost MeSH
• rizikové faktory MeSH
• Check Tag
• lidé MeSH
• Publikační typ
• časopisecké články MeSH
• Research Support, N.I.H., Extramural MeSH

• Publikační typ
• úvodníky MeSH