Recurrent APC gene mutations in Polish FAP families

The molecular diagnostics of genetically conditioned disorders is based on the identification of the mutations in the predisposing genes. Hereditary cancer disorders of the gastrointestinal tracts are caused by mutations of the tumour suppressor genes or the DNA repair genes. Occurrence of recurrent mutation allows improvement of molecular diagnostics. The mutation spectrum in the genes causing hereditary forms of colorectal cancers in the Polish population was previously described. In the present work an estimation of the frequency of the recurrent mutations of the APC gene was performed. Eight types of mutations occurred in 19.4% of our FAP families and these constitute 43% of all Polish diagnosed families

Non-Coding RNAs in Cancer Radiosensitivity:MicroRNAs and lncRNAs as Regulators of Radiation-Induced Signaling Pathways

Radiotherapy is a cancer treatment that applies high doses of ionizing radiation to induce cell death, mainly by triggering DNA double-strand breaks. The outcome of radiotherapy greatly depends on radiosensitivity of cancer cells, which is determined by multiple proteins and cellular processes. In this review, we summarize current knowledge on the role of microRNAs (miRNAs) and long non-coding RNAs (lncRNAs), in determining the response to radiation. Non-coding RNAs modulate ionizing radiation response by targeting key signaling pathways, including DNA damage repair, apoptosis, glycolysis, cell cycle arrest, and autophagy. Additionally, we indicate miRNAs and lncRNAs that upon overexpression or inhibition alter cellular radiosensitivity. Current data indicate the potential of using specific non-coding RNAs as modulators of cellular radiosensitivity to improve outcome of radiotherapy

CRISPR/Cas9 screen for genome-wide interrogation of essential MYC-bound E-boxes in cancer cells

The transcription factor MYC is a proto-oncogene with a well-documented essential role in the pathogenesis and maintenance of several types of cancer. MYC binds to specific E-box sequences in the genome to regulate gene expression in a cell-type- and developmental-stage-specific manner. To date, a combined analysis of essential MYC-bound E-boxes and their downstream target genes important for growth of different types of cancer is missing. In this study, we designed a CRISPR/Cas9 library to destroy E-box sequences in a genome-wide fashion. In parallel, we used the Brunello library to knock out protein-coding genes. We performed high-throughput screens with these libraries in four MYC-dependent cancer cell lines - K562, ST486, HepG2 and MCF7 - which revealed several essential E-boxes and genes. Among them we pinpointed crucial common and cell-type-specific MYC-regulated genes involved in pathways associated with cancer development. Extensive validation of our approach confirmed that E-box disruption affects MYC binding, target-gene expression and cell proliferation in vitro as well as tumor growth in vivo. Our unique, well-validated tool opens new possibilities to gain novel insights into MYC-dependent vulnerabilities in cancer cells.</p

CRISPR/Cas9 screen for genome-wide interrogation of essential MYC-bound E-boxes in cancer cells

The transcription factor MYC is a proto-oncogene with a well-documented essential role in the pathogenesis and maintenance of several types of cancer. MYC binds to specific E-box sequences in the genome to regulate gene expression in a cell-type- and developmental-stage-specific manner. To date, a combined analysis of essential MYC-bound E-boxes and their downstream target genes important for growth of different types of cancer is missing. In this study, we designed a CRISPR/Cas9 library to destroy E-box sequences in a genome-wide fashion. In parallel, we used the Brunello library to knock out protein-coding genes. We performed high-throughput screens with these libraries in four MYC-dependent cancer cell lines - K562, ST486, HepG2 and MCF7 - which revealed several essential E-boxes and genes. Among them we pinpointed crucial common and cell-type-specific MYC-regulated genes involved in pathways associated with cancer development. Extensive validation of our approach confirmed that E-box disruption affects MYC binding, target-gene expression and cell proliferation in vitro as well as tumor growth in vivo. Our unique, well-validated tool opens new possibilities to gain novel insights into MYC-dependent vulnerabilities in cancer cells.</p

Nadekspresja miR-652-5p u chorych z nowo rozpoznaną cukrzycą typu 1

Wstęp. MicroRNA (miRNA) to krótkie, niekodujące RNA, które regulują ekspresję genów na poziomie potransktypcyjnym. Cząsteczki miRNA odgrywają istotną rolę w regulacji centralnej i obwodowej tolerancji immunologicznej, dlatego analiza niekodujących RNA w cukrzycy typu 1 (T1D) jest istotnym problemem badawczym. Celem badania była analiza ekspresji miR-652-5p w nowo zdiagnozowanych przypadkach cukrzycy typu 1 oraz ocena miejsc wiązania miR-652-5p w potencjalnych genach docelowych ADAR i MARCH5. Metody. Analiza ekspresji miR-652-5p została przeprowadzona w komórkach jednojądrzastych krwi obwodowej dzieci z nowo rozpoznaną cukrzycą typu 1 (n = 28) oraz w dobranej pod względem wieku grupie kontrolnej (n = 28) na podstawie metody PCR w czasie rzeczywistym. Miejsca wiązania miR-652-5p w genach docelowych zostały ocenione z wykorzystaniem układu reporterowego lucyferazy. Wyniki. Analiza ekspresji wykazała podwyższony poziom miR-652-5p u pacjentów z T1D w porównaniu z grupą zdrowych dawców (p &lt; 0,05). Ocena miejsc wiązania w układzie reporterowym lucyferazy nie wskazała genu ADAR i MARCH5 jako potencjalnych genów docelowych miR-652-5p. Wnioski. Przeprowadzone badania wskazały miR-652-5p jako potencjalny biomarker cukrzycy typu 1

Non-Coding RNAs in Cancer Radiosensitivity: MicroRNAs and lncRNAs as Regulators of Radiation-Induced Signaling Pathways

Radiotherapy is a cancer treatment that applies high doses of ionizing radiation to induce cell death, mainly by triggering DNA double-strand breaks. The outcome of radiotherapy greatly depends on radiosensitivity of cancer cells, which is determined by multiple proteins and cellular processes. In this review, we summarize current knowledge on the role of microRNAs (miRNAs) and long non-coding RNAs (lncRNAs), in determining the response to radiation. Non-coding RNAs modulate ionizing radiation response by targeting key signaling pathways, including DNA damage repair, apoptosis, glycolysis, cell cycle arrest, and autophagy. Additionally, we indicate miRNAs and lncRNAs that upon overexpression or inhibition alter cellular radiosensitivity. Current data indicate the potential of using specific non-coding RNAs as modulators of cellular radiosensitivity to improve outcome of radiotherapy