Small noncoding RNAs play an important role in various disease states, including cancer. PIWI proteins, a subfamily of Argonaute proteins, and PIWI-interacting RNAs (piRNAs) were originally described as germline-specific molecules that inhibit the deleterious activity of transposable elements. However, several studies have suggested a role for the piRNA-PIWI axis in somatic cells, including somatic stem cells. Dysregulated expression of piRNAs and PIWI proteins in human tumors implies that, analogously to their roles in undifferentiated cells under physiological conditions, these molecules may be important for cancer stem cells and thus contribute to cancer progression. We provide an overview of piRNA biogenesis and critically review the evidence for the role of piRNA-PIWI axis in cancer stem cells. In addition, we examine the potential of piRNAs and PIWI proteins to become biomarkers in cancer.
- Klíčová slova
- Cancer, Cancer stem cells, PIWI proteins, PIWI-interacting RNAs, piRNAs,
- Publikační typ
- časopisecké články MeSH
- přehledy MeSH
Endometrial biopsies are important in the diagnostic workup of women who present with abnormal uterine bleeding or hereditary risk of endometrial cancer. In general, approximately 10% of all endometrial biopsies demonstrate endometrial (pre)malignancy that requires specific treatment. As the diagnostic evaluation of mostly benign cases results in a substantial workload for pathologists, artificial intelligence (AI)-assisted preselection of biopsies could optimize the workflow. This study aimed to assess the feasibility of AI-assisted diagnosis for endometrial biopsies (endometrial Pipelle biopsy computer-aided diagnosis), trained on daily-practice whole-slide images instead of highly selected images. Endometrial biopsies were classified into 6 clinically relevant categories defined as follows: nonrepresentative, normal, nonneoplastic, hyperplasia without atypia, hyperplasia with atypia, and malignant. The agreement among 15 pathologists, within these classifications, was evaluated in 91 endometrial biopsies. Next, an algorithm (trained on a total of 2819 endometrial biopsies) rated the same 91 cases, and we compared its performance using the pathologist's classification as the reference standard. The interrater reliability among pathologists was moderate with a mean Cohen's kappa of 0.51, whereas for a binary classification into benign vs (pre)malignant, the agreement was substantial with a mean Cohen's kappa of 0.66. The AI algorithm performed slightly worse for the 6 categories with a moderate Cohen's kappa of 0.43 but was comparable for the binary classification with a substantial Cohen's kappa of 0.65. AI-assisted diagnosis of endometrial biopsies was demonstrated to be feasible in discriminating between benign and (pre)malignant endometrial tissues, even when trained on unselected cases. Endometrial premalignancies remain challenging for both pathologists and AI algorithms. Future steps to improve reliability of the diagnosis are needed to achieve a more refined AI-assisted diagnostic solution for endometrial biopsies that covers both premalignant and malignant diagnoses.
- Klíčová slova
- classification, digital pathology, endometrial cancer, interobserver variability,
- MeSH
- biopsie MeSH
- hyperplazie MeSH
- lidé MeSH
- počítače * MeSH
- reprodukovatelnost výsledků MeSH
- studie proveditelnosti MeSH
- umělá inteligence * MeSH
- Check Tag
- lidé MeSH
- ženské pohlaví MeSH
- Publikační typ
- časopisecké články MeSH
AIMS: The authors focused on a group of young lung cancer patients with the aim of better understanding the mechanisms of tumor pathogenesis in these patients and search for potential targetable mutations. METHODS: We collected retrospective data on patients under 40 years diagnosed with lung cancer (NSCLC or small-cell lung cancer) from 2011-2020 at the Department of Respiratory Diseases, University Hospital Brno, Czech Republic. Tumor tissue of these patients was analysed by next-generation sequencing (NGS, a panel of 550 variants in 19 genes). Demographic characteristics, smoking history, histology, molecular-genetic results and clinical stage of the disesase were recorded in all eligible patients from accessible medical databases. RESULTS: Of 17 identified patients in only 8 cases was successful NGS carried out due to lack of sufficient good quality material in the other cases. The most frequently found molecular genetic changes were EGFR, RICTOR and HER2 amplification and MET and FGFR1 amplification. In addition, we found rare pathogenic variants in BRAF and PIK3CA genes. Actionable variants were detected in 75% patients. CONCLUSION: We detected very frequent driver and potentially actionable alterations in young patients with lung cancer. This suggests different mechanisms of carcinogenesis in these patients and indicates that they might benefit more from a specific approach than older lung cancer patients.
- Klíčová slova
- driver, lung cancer, mutation, young patient,
- MeSH
- lidé MeSH
- malobuněčný karcinom plic * MeSH
- mutace MeSH
- nádory plic * genetika patologie MeSH
- nemalobuněčný karcinom plic * genetika MeSH
- retrospektivní studie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
BACKGROUND/AIM: Brain metastases (BMs) are the most frequent intracranial tumors in adults and one of the greatest challenges for modern oncology. Most are derived from lung, breast, renal cell, and colorectal carcinomas and melanomas. Up to 14% of patients are diagnosed with BMs of unknown primary, which are commonly characterized by an early and aggressive metastatic spread. It is important to discover novel biomarkers for early identification of BM origin, allowing better management of patients with this disease. Our study focused on microRNAs (miRNAs), which are very stable in frozen native and FFPE tissues and have been shown to be sensitive and specific diagnostic biomarkers of cancer. We aimed to identify miRNAs with significantly different expression in the five most frequent groups of BMs and develop a diagnostic classifier capable of sensitive and specific classification of BMs. MATERIALS AND METHODS: Total RNA enriched for miRNAs was isolated using the mirVana miRNA Isolation Kit from 71 fresh-frozen histopathologically confirmed BM tissues originating in 5 cancer types. Sequencing libraries were prepared using the QIAseq miRNA Library Kit and sequenced on the NextSeq 500 platform. MiRNA expression was further validated by RT-qPCR. RESULTS: Differential analysis identified 373 miRNAs with significantly different expression between 5 BM groups (p<0.001). A classifier model was developed based on the expression of 6 miRNAs (hsa-miR-141-3p, hsa-miR-141-5p, hsa-miR-146a-5p, hsa-miR-194-5p, hsa-miR-200b-3p and hsa-miR-365b-5p) with the ability to correctly classify 91.5% of samples. Subsequent validation confirmed both significantly different expression of selected miRNAs in 5 BM groups as well as their diagnostic potential. CONCLUSION: To date, our study is the first to analyze miRNA expression in various types of BMs using small RNA sequencing to develop a diagnostic classifier and, thus, to help stratify BMs of unknown primary. The presented results confirm the importance of studying the dysregulated expression of miRNAs in BMs and the diagnostic potential of the validated 6-miRNA signature.
- Klíčová slova
- Brain metastases, classifier, diagnosis, microRNA, small RNA sequencing,
- MeSH
- biologické markery MeSH
- dospělí MeSH
- lidé MeSH
- melanom * MeSH
- mikro RNA * genetika metabolismus MeSH
- nádory mozku * genetika MeSH
- nádory neznámé primární lokalizace * MeSH
- Check Tag
- dospělí MeSH
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- biologické markery MeSH
- mikro RNA * MeSH
BACKGROUND/AIM: Glioblastoma (GBM) is one of the deadliest human cancers responding very poorly to therapy. Although the central nervous system has been traditionally considered an immunologically privileged site with an enhanced immune response, GBM appears to benefit from this immunosuppressive milieu. Immunomodulatory molecules play an important role in immune tumor-host interactions. Non-classical human leukocyte antigens (HLA) class Ib molecules HLA-E, HLA-F, and HLA-G have been previously described to be involved in protecting semi-allogeneic fetal allografts from the maternal immune response and in transplant tolerance as well as tumoral immune escape. Unfortunately, their role in GBM remains poorly understood. Our study, therefore, aimed to characterize the relationship between the expression of these molecules in GBM on the transcriptional level and clinicopathological and molecular features of GBM as well as the effect of ionizing radiation. MATERIALS AND METHODS: We performed the analysis of HLA-E, HLA-F, and HLA-G mRNA expression in 69 GBM tissue samples and 21 non-tumor brain tissue samples (controls) by reverse transcription polymerase chain reaction. Furthermore, two primary GBM cell cultures had been irradiated to identify the effect of ionizing radiation on the expression of non-classical HLA molecules. RESULTS: Analyses revealed that both HLA-E and HLA-F are significantly up-regulated in GBM samples. Subsequent survival analysis showed a significant association between low expression of HLA-E and shorter survival of GBM patients. The dysregulated expression of both molecules was also observed between patients with methylated and unmethylated O-6-methylguanine-DNA methyltransferase (MGMT) promoter. Finally, we showed that ionizing radiation increased HLA-E expression level in GBM cells in vitro. CONCLUSION: HLA-E and HLA-F play an important role in GBM biology and could be used as diagnostic biomarkers, and in the case of HLA-E also as a prognostic biomarker.
- Klíčová slova
- Glioblastoma, HLA-E, HLA-F, ionizing radiation, non-classical human leukocyte antigens, prognosis,
- MeSH
- antigeny HLA-E MeSH
- glioblastom * genetika patologie radioterapie MeSH
- histokompatibilita - antigeny třídy I * biosyntéza genetika MeSH
- ionizující záření MeSH
- lidé MeSH
- metylace DNA MeSH
- nádory mozku * genetika patologie radioterapie MeSH
- prognóza MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- Názvy látek
- histokompatibilita - antigeny třídy I * MeSH
- HLA-F antigens MeSH Prohlížeč
The transcription factor c-Myb is an oncoprotein promoting cell proliferation and survival when aberrantly activated/expressed, thus contributing to malignant transformation. Overexpression of c-Myb has been found in leukemias, breast, colon and adenoid cystic carcinoma. Recent studies revealed its expression also in osteosarcoma cell lines and suggested its functional importance during bone development. However, the relevance of c-Myb in control of osteosarcoma progression remains unknown. A retrospective clinical study was carried out to assess a relationship between c-Myb expression in archival osteosarcoma tissues and prognosis in a cohort of high-grade osteosarcoma patients. In addition, MYB was depleted in metastatic osteosarcoma cell lines SAOS-2 LM5 and 143B and their growth, chemosensitivity, migration and metastatic activity were determined. Immunohistochemical analysis revealed that high c-Myb expression was significantly associated with poor overall survival in the cohort and metastatic progression in young patients. Increased level of c-Myb was detected in metastatic osteosarcoma cell lines and its depletion suppressed their growth, colony-forming capacity, migration and chemoresistance in vitro in a cell line-dependent manner. MYB knock-out resulted in reduced metastatic activity of both SAOS-2 LM5 and 143B cell lines in immunodeficient mice. Transcriptomic analysis revealed the c-Myb-driven functional programs enriched for genes involved in the regulation of cell growth, stress response, cell adhesion and cell differentiation/morphogenesis. Wnt signaling pathway was identified as c-Myb target in osteosarcoma cells. Taken together, we identified c-Myb as a negative prognostic factor in osteosarcoma and showed its involvement in the regulation of osteosarcoma cell growth, chemosensitivity, migration and metastatic activity.
- Klíčová slova
- Chemoresistance, Metastasis, Osteosarcoma, Prognosis, Proliferation, c-Myb,
- MeSH
- lidé MeSH
- myši MeSH
- nádorové buněčné linie MeSH
- nádory kostí * patologie MeSH
- osteosarkom * patologie MeSH
- pohyb buněk genetika MeSH
- prognóza MeSH
- proliferace buněk MeSH
- regulace genové exprese u nádorů MeSH
- retrospektivní studie MeSH
- signální dráha Wnt MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
Identification of changes of phospholipid (PL) composition occurring during colorectal cancer (CRC) development may help us to better understand their roles in CRC cells. Here, we used LC-MS/MS-based PL profiling of cell lines derived from normal colon mucosa, or isolated at distinct stages of CRC development, in order to study alterations of PL species potentially linked with cell transformation. We found that a detailed evaluation of phosphatidylinositol (PI) and phosphatidylserine (PS) classes allowed us to cluster the studied epithelial cell lines according to their origin: i) cells originally derived from normal colon tissue (NCM460, FHC); ii) cell lines derived from colon adenoma or less advanced differentiating adenocarcinoma cells (AA/C1, HT-29); or, iii) cells obtained by in vitro transformation of adenoma cells and advanced colon adenocarcinoma cells (HCT-116, AA/C1/SB10, SW480, SW620). Although we tentatively identified several PS and PI species contributing to cell line clustering, full PI and PS profiles appeared to be a key to the successful cell line discrimination. In parallel, we compared PL composition of primary epithelial (EpCAM-positive) cells, isolated from tumor and adjacent non-tumor tissues of colon cancer patients, with PL profiles of cell lines derived from normal colon mucosa (NCM460) and from colon adenocarcinoma (HCT-116, SW480) cells, respectively. In general, higher total levels of all PL classes were observed in tumor cells. The overall PL profiles of the cell lines, when compared with the respective patient-derived cells, exhibited similarities. Nevertheless, there were also some notable differences in levels of individual PL species. This indicated that epithelial cell lines, derived either from normal colon tissue or from CRC cells, could be employed as models for functional lipidomic analyses of colon cells, albeit with some caution. The biological significance of the observed PL deregulation, or their potential links with specific CRC stages, deserve further investigation.
- MeSH
- analýza hlavních komponent MeSH
- epitelové buňky metabolismus patologie MeSH
- fosfolipidy metabolismus MeSH
- kolon patologie MeSH
- lidé MeSH
- lipidomika * MeSH
- nádorové buněčné linie MeSH
- nádory tračníku metabolismus patologie MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- fosfolipidy MeSH
Chronic lymphocytic leukemia (CLL) represents a prototype disease in which TP53 gene defects lead to inferior prognosis. Here, we present two distinct methodologies which can be used to identify TP53 mutations in CLL patients; both protocols are primarily intended for research purposes. The functional analysis of separated alleles in yeast (FASAY) can be flexibly adapted to a variable number of samples and provides an immediate functional readout of identified mutations. Amplicon-based next-generation sequencing then allows for a high throughput and accurately detects subclonal TP53 variants (sensitivity <1% of mutated cells).
- Klíčová slova
- FASAY, Low-burden mutations, Next-generation sequencing, Subclonal mutations, TP53,
- MeSH
- alely MeSH
- chronická lymfatická leukemie krev genetika patologie MeSH
- lidé MeSH
- mutace MeSH
- mutační analýza DNA přístrojové vybavení metody MeSH
- nádorové cirkulující buňky patologie MeSH
- nádorový supresorový protein p53 genetika MeSH
- reportérové geny genetika MeSH
- Saccharomyces cerevisiae genetika MeSH
- transfekce přístrojové vybavení metody MeSH
- vysoce účinné nukleotidové sekvenování přístrojové vybavení metody MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- nádorový supresorový protein p53 MeSH
- TP53 protein, human MeSH Prohlížeč
Follicular lymphoma (FL) is a common indolent B-cell malignancy with a variable clinical course. An unfavorable event in its course is histological transformation to a high-grade lymphoma, typically diffuse large B-cell lymphoma. Recent studies show that genetic aberrations of MYC or its overexpression are associated with FL transformation (tFL). However, the precise molecular mechanisms underlying tFL are unclear. Here we performed the first profiling of expression of microRNAs (miRNAs) in paired samples of FL and tFL and identified 5 miRNAs as being differentially expressed. We focused on one of these miRNAs, namely miR-150, which was uniformly downmodulated in all examined tFLs (∼3.5-fold), and observed that high levels of MYC are responsible for repressing miR-150 in tFL by binding in its upstream region. This MYC-mediated repression of miR-150 in B cells is not dependent on LIN28A/B proteins, which influence the maturation of miR-150 precursor (pri-miR-150) in myeloid cells. We also demonstrated that low miR-150 levels in tFL lead to upregulation of its target, namely FOXP1 protein, which is a known positive regulator of cell survival, as well as B-cell receptor and NF-κB signaling in malignant B cells. We revealed that low levels of miR-150 and high levels of its target, FOXP1, are associated with shorter overall survival in FL and suggest that miR-150 could serve as a good biomarker measurable in formalin-fixed paraffin-embedded tissue. Overall, our study demonstrates the role of the MYC/miR-150/FOXP1 axis in malignant B cells as a determinant of FL aggressiveness and its high-grade transformation.
- MeSH
- aktivace transkripce MeSH
- difúzní velkobuněčný B-lymfom genetika patologie MeSH
- down regulace MeSH
- folikulární lymfom diagnóza genetika patologie MeSH
- forkhead transkripční faktory genetika MeSH
- lidé MeSH
- mikro RNA genetika MeSH
- nádorová transformace buněk genetika patologie MeSH
- prognóza MeSH
- protoonkogenní proteiny c-myc genetika MeSH
- regulace genové exprese u nádorů * MeSH
- represorové proteiny genetika MeSH
- upregulace MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Názvy látek
- forkhead transkripční faktory MeSH
- FOXP1 protein, human MeSH Prohlížeč
- mikro RNA MeSH
- MIRN150 microRNA, human MeSH Prohlížeč
- protoonkogenní proteiny c-myc MeSH
- represorové proteiny MeSH
- Klíčová slova
- CLL, NOTCH1 mutation, TP53 mutations, clonal evolution, single cell analysis,
- MeSH
- alely MeSH
- analýza jednotlivých buněk metody MeSH
- chronická lymfatická leukemie diagnóza farmakoterapie genetika MeSH
- genotyp MeSH
- klonální evoluce genetika MeSH
- lidé MeSH
- mutační analýza DNA metody MeSH
- nádorový supresorový protein p53 genetika MeSH
- receptor Notch1 genetika MeSH
- Check Tag
- lidé MeSH
- Publikační typ
- dopisy MeSH
- práce podpořená grantem MeSH
- Názvy látek
- nádorový supresorový protein p53 MeSH
- receptor Notch1 MeSH
