Can long-read sequencing tackle the barriers, which the next-generation could not? A review.

The large-scale heterogeneity of genetic diseases necessitated the deeper examination of nucleotide sequence alterations enhancing the discovery of new targeted drug attack points. The appearance of new sequencing techniques was essential to get more interpretable genomic data. In contrast to the previous short-reads, longer lengths can provide a better insight into the potential health threatening genetic abnormalities. Long-reads offer more accurate variant identification and genome assembly methods, indicating advances in nucleotide deflect-related studies. In this review, we introduce the historical background of sequencing technologies and show their benefits and limits, as well. Furthermore, we highlight the differences between short- and long-read approaches, including their unique advances and difficulties in methodologies and evaluation. Additionally, we provide a detailed description of the corresponding bioinformatics and the current applications.

Short-range translocation by a restriction enzyme motor triggers diffusion along DNA.

Cleavage of bacteriophage DNA by the Type III restriction-modification enzymes requires long-range interaction between DNA sites. This is facilitated by one-dimensional diffusion ('DNA sliding') initiated by ATP hydrolysis catalyzed by a superfamily 2 helicase-like ATPase. Here we combined ultrafast twist measurements based on plasmonic DNA origami nano-rotors with stopped-flow fluorescence and gel-based assays to examine the role(s) of ATP hydrolysis. Our data show that the helicase-like domain has multiple roles. First, this domain stabilizes initial DNA interactions alongside the methyltransferase subunits. Second, it causes environmental changes in the flipped adenine base following hydrolysis of the first ATP. Finally, it remodels nucleoprotein interactions via constrained translocation of a ∼ 5 to 22-bp double stranded DNA loop. Initiation of DNA sliding requires 8-15 bp of DNA downstream of the motor, corresponding to the site of nuclease domain binding. Our data unify previous contradictory communication models for Type III enzymes.

Long term follow-up of refractory/relapsed hairy cell leukaemia patients treated with low-dose vemurafenib between 2013 and 2022 at the Department of Internal Medicine and Oncology, Semmelweis University.

Introduction: Hairy cell leukemia (HCL) is an indolent B-cell lymphoproliferative disease. BRAF V600E mutation is detected in nearly all classical HCL cases which offers the possibility of targeted therapy. Objective: The aim of our study was to assess the efficacy of low-dose vemurafenib as well as to assess the long term outcome of HCL patients treated with this drug at the Department of Internal Medicine and Oncology at Semmelweis University. Methods: We report on 10 patients with classical HCL treated with low-dose vemurafenib at our Department between 2013 and 2022. Results: As a result of fixed time low-dose vemurafenib treatment, 5 of 10 patients (5/10) achieved partial remission, 4 (4/10) had stable disease, and 1 (1/10) had MRD positivity. No patients achieved complete remission. The median progression-free survival was 28.5 months while the overall survival was 82 months. Conclusion: We confirm that low dose of vemurafenib is effective and safe in the vast majority of patients with HCL. This small-molecule oral treatment allows to gain valuable time-months or even years-before further, usually parenteral treatment options have to be given or before previous treatment has to be repeated. There are also promising data supporting the combination of vemurafenib with other drugs for the treatment of HCL patients which could provide even further possibility to bridge treatment.

[Multicentric Hungarian results of cabozantinib therapy in patients with metastatic kidney cancer based on real-world data]. / Áttétes vesedaganatos betegek kabozantinibterápiájának multicentrikus magyarországi eredményei.

The aim of our analysis was to evaluate the efficacy of cabozantinib in patients with metastatic renal cell carcinoma. Cabozantinib therapy initiated between 01/01/2019 and 31/12/2022 was evaluated based on a retrospective review of data from 14 renal centers in Hungary. The starting dose was 60 or 40 mg. Physical examinations and laboratory tests were performed every 4 weeks and imaging studies 3-monthly. Tumor response was assessed according to RECIST 1.1, and toxicity according to NCI CTCAE 4.0. A total of 230 patient records were evaluated, 201 (87.4%) of them had clear cell RCC. Cabozantinib was administered as third, second and first-line treatment in 48.7%, 38.3% and <5% of cases, respectively. Dose reductions occurred in 62.6% and treatment interruption in 6.5%. Duration of therapy was 10.03 months, which was independent of dose reduction. Overall tumor response rate was 39.2% and clinical benefit was 82.8%. The duration of first-, second-, third- and fourth-line treatment was 11.47, 8.03, 11.57 and 10.13 months, respectively. Overall survival from the start of therapy was 22.0 months. Cabozantinib therapy in daily practice was more beneficial than according to registry study results. Dose reduction did not affect efficacy.

[Multicentric Hungarian results of cabozantinib therapy in patients with metastatic kidney cancer based on real-world data]. / Áttétes vesedaganatos betegek kabozantinibterápiájának multicentrikus magyarországi eredményei.

The aim of our analysis was to evaluate the efficacy of cabozantinib in patients with metastatic renal cell carcinoma. Cabozantinib therapy initiated between 01/01/2019 and 31/12/2022 was evaluated based on a retrospective review of data from 14 renal centers in Hungary. The starting dose was 60 or 40 mg. Physical examinations and laboratory tests were performed every 4 weeks and imaging studies 3-monthly. Tumor response was assessed according to RECIST 1.1, and toxicity according to NCI CTCAE 4.0. A total of 230 patient records were evaluated, 201 (87.4%) of them had clear cell RCC. Cabozantinib was administered as third, second and first-line treatment in 48.7%, 38.3% and <5% of cases, respectively. Dose reductions occurred in 62.6% and treatment interruption in 6.5%. Duration of therapy was 10.03 months, which was independent of dose reduction. Overall tumor response rate was 39.2% and clinical benefit was 82.8%. The duration of first-, second-, third- and fourth-line treatment was 11.47, 8.03, 11.57 and 10.13 months, respectively. Overall survival from the start of therapy was 22.0 months. Cabozantinib therapy in daily practice was more beneficial than according to registry study results. Dose reduction did not affect efficacy.

Patterns of Somatic Variants in Colorectal Adenoma and Carcinoma Tissue and Matched Plasma Samples from the Hungarian Oncogenome Program.

Analysis of circulating cell-free DNA (cfDNA) of colorectal adenoma (AD) and cancer (CRC) patients provides a minimally invasive approach that is able to explore genetic alterations. It is unknown whether there are specific genetic variants that could explain the high prevalence of CRC in Hungary. Whole-exome sequencing (WES) was performed on colon tissues (27 AD, 51 CRC) and matched cfDNAs (17 AD, 33 CRC); furthermore, targeted panel sequencing was performed on a subset of cfDNA samples. The most frequently mutated genes were APC, KRAS, and FBN3 in AD, while APC, TP53, TTN, and KRAS were the most frequently mutated in CRC tissue. Variants in KRAS codons 12 (AD: 8/27, CRC: 11/51 (0.216)) and 13 (CRC: 3/51 (0.06)) were the most frequent in our sample set, with G12V (5/27) dominance in ADs and G12D (5/51 (0.098)) in CRCs. In terms of the cfDNA WES results, tumor somatic variants were found in 6/33 of CRC cases. Panel sequencing revealed somatic variants in 8 out of the 12 enrolled patients, identifying 12/20 tumor somatic variants falling on its targeted regions, while WES recovered only 20% in the respective regions in cfDNA of the same patients. In liquid biopsy analyses, WES is less efficient compared to the targeted panel sequencing with a higher coverage depth that can hold a relevant clinical potential to be applied in everyday practice in the future.

[Prognostic significance of variant left common pulmonary vein after transcatheter pulmonary vein isolation]. / A variáns bal oldali közös tüdovéna prognosztikus jelentosége transzkatéteres tüdovéna-izolációt követoen.

INTRODUCTION: Left common pulmonary vein is the most common anatomical variant of pulmonary veins that may affect the outcome of pulmonary vein isolation. OBJECTIVE: Our aim was to compare procedural data and outcomes in patients with common trunk versus normal left atrial anatomy for radiofrequency and cryoballoon catheter ablation. METHOD: Data from patients who underwent pulmonary vein isolation for atrial fibrillation and had a preprocedural cardiac CT scan at our Institution between 01. 10. 2019 and 10. 03. 2022 were retrospectively evaluated. We defined a common trunk where the left superior and inferior pulmonary vein merged at least 5 mm before the left atrial ostium. RESULTS: From the study population (n = 210), data from 42 patients with a left common trunk (LCPV group) and 60 patients with normal left atrial anatomy (control group) were examined. No significant differences were found between the common trunk and the control group in terms of demographic data. There was no significant difference between the two groups in procedural data for radiofrequency and cryoballoon ablation (procedure time, fluoroscopy time, left atrial dwelling time, radiation dose). After radiofrequency ablation, the success rate at 1-year follow-up was 72.0% in the common trunk group and 76.2% in the control group (p = 0.659). For cryoballoon ablation, the success rate was 64.7% and 69.2% for common trunk and normal anatomy, respectively (p = 0.641). CONCLUSION: There was no significant difference in the procedural parameters and clinical outcome between patients with left common pulmonary vein and those with normal left atrial anatomy. Both radiofrequency and cryoballoon ablation techniques are well suited for this population. Orv Hetil. 2023; 164(4): 140-147.

New computational fluid dynamics-based method for morphological and functional assessment in cardiovascular skill training.

Objective: During cardiovascular surgical skill training, the direct quantification regarding surgical performance is still lacking, including transferring clinically relevant information. Methods: We introduced a novel computational fluid dynamics-based method in support of vascular surgical hands-on training, which applies continuous self-assessment in vascular anastomoses. The validation of the methodology was implemented in comparing with conventional training courses. Results: The fifth and seventh consecutive anastomoses of the experimental group showed significantly improved results regarding anastomosis quality when compared with the control group. Conclusions: Consecutive demonstration of three-dimensional morphology and functional assessment of anastomoses results in improved practical performance among learners regarding anastomosis quality.

Full Body Surface Coverage with Water-Equivalent Bolus as Novel Technique for Total Body Irradiation before Hematopoietic Stem Cell Transplantation in Pediatric Acute Lymphoid Leukemia.

BACKGROUND: Total body irradiation (TBI) 2 × 2 Gy for 3 consecutive days followed by chemotherapy for conditioning pediatric patients with acute lymphoid leukemia (ALL) before bone marrow transplantation is superior to chemo-conditioning alone. The globally used anterior-posterior/posterior-anterior (AP/PA) technique is the most referable method, but volumetric modulated arc therapy (VMAT) with modern linear accelerators is more precise in terms of ensuring better dose distribution, especially for skin, and higher protection of organs at risk, resulting in less side effects. METHOD: For TBI, a modern VMAT technique was used. Whole-body immobilization in the supine position was performed using a vacuum mattress with a full body coverage, with a water-equivalent bolus of 1 cm thickness. The design goal was to achieve dose inhomogeneity of less than ±10%. RESULTS: From 2020 to 2022, we performed TBI for five pediatric patients with ALL, with full body bolus and VMAT, who later received hematopoietic stem cell transplantation. No acute complications related to TBI were observed during the treatment period with a median follow-up of 1.27 (0.43-2.11) years. CONCLUSION: Using full body water-equivalent bolus with VMAT for TBI provides a safe method for children with a better organ sparing in the short term follow-up.

Methodological and Biological Factors Influencing Global DNA Methylation Results Measured by LINE-1 Pyrosequencing Assay in Colorectal Tissue and Liquid Biopsy Samples.

Long interspersed nuclear element 1 (LINE-1) bisulfite pyrosequencing is a widely used technique for genome-wide methylation analyses. We aimed to investigate the effects of experimental and biological factors on its results to improve the comparability. LINE-1 bisulfite pyrosequencing was performed on colorectal tissue (n = 222), buffy coat (n = 39), and plasma samples (n = 9) of healthy individuals and patients with colorectal tumors. Significantly altered methylation was observed between investigated LINE-1 CpG positions of non-tumorous tissues (p ≤ 0.01). Formalin-fixed, paraffin-embedded biopsies (73.0 ± 5.3%) resulted in lower methylation than fresh frozen samples (76.1 ± 2.8%) (p ≤ 0.01). DNA specimens after long-term storage showed higher methylation levels (+3.2%, p ≤ 0.01). In blood collection tubes with preservatives, cfDNA and buffy coat methylation significantly changed compared to K3EDTA tubes (p ≤ 0.05). Lower methylation was detected in older (>40 years, 76.8 ± 1.7%) vs. younger (78.1 ± 1.0%) female patients (p ≤ 0.05), and also in adenomatous tissues with MTHFR 677CT, or 1298AC mutations vs. wild-type (p ≤ 0.05) comparisons. Based on our findings, it is highly recommended to consider the application of standard DNA samples in the case of a possible clinical screening approach, as well as in experimental research studies.

A Detailed Overview About the Single-Cell Analyses of Solid Tumors Focusing on Colorectal Cancer.

In recent years, the evolution of the molecular biological technical background led to the widespread application of single-cell sequencing, a versatile tool particularly useful in the investigation of tumor heterogeneity. Even 10 years ago the comprehensive characterization of colorectal cancers by The Cancer Genome Atlas was based on measurements of bulk samples. Nowadays, with single-cell approaches, tumor heterogeneity, the tumor microenvironment, and the interplay between tumor cells and their surroundings can be described in unprecedented detail. In this review article we aimed to emphasize the importance of single-cell analyses by presenting tumor heterogeneity and the limitations of conventional investigational approaches, followed by an overview of the whole single-cell analytic workflow from sample isolation to amplification, sequencing and bioinformatic analysis and a review of recent literature regarding the single-cell analysis of colorectal cancers.

Global DNA hypomethylation of colorectal tumours detected in tissue and liquid biopsies may be related to decreased methyl-donor content.

BACKGROUND: Hypomethylation of long interspersed nuclear element 1 (LINE-1) is characteristic of various cancer types, including colorectal cancer (CRC). Malfunction of several factors or alteration of methyl-donor molecules' (folic acid and S-adenosylmethionine) availability can contribute to DNA methylation changes. Detection of epigenetic alterations in liquid biopsies can assist in the early recognition of CRC. Following the investigations of a Hungarian colon tissue sample set, our goal was to examine the LINE-1 methylation of blood samples along the colorectal adenoma-carcinoma sequence and in inflammatory bowel disease. Moreover, we aimed to explore the possible underlying mechanisms of global DNA hypomethylation formation on a multi-level aspect. METHODS: LINE-1 methylation of colon tissue (n = 183) and plasma (n = 48) samples of healthy controls and patients with colorectal tumours were examined with bisulfite pyrosequencing. To investigate mRNA expression, microarray analysis results were reanalysed in silico (n = 60). Immunohistochemistry staining was used to validate DNA methyltransferases (DNMTs) and folate receptor beta (FOLR2) expression along with the determination of methyl-donor molecules' in situ level (n = 40). RESULTS: Significantly decreased LINE-1 methylation level was observed in line with cancer progression both in tissue (adenoma: 72.7 ± 4.8%, and CRC: 69.7 ± 7.6% vs. normal: 77.5 ± 1.7%, p ≤ 0.01) and liquid biopsies (adenoma: 80.0 ± 1.7%, and CRC: 79.8 ± 1.3% vs. normal: 82.0 ± 2.0%, p ≤ 0.01). However, no significant changes were recognized in inflammatory bowel disease cases. According to in silico analysis of microarray data, altered mRNA levels of several DNA methylation-related enzymes were detected in tumours vs. healthy biopsies, namely one-carbon metabolism-related genes-which met our analysing criteria-showed upregulation, while FOLR2 was downregulated. Using immunohistochemistry, DNMTs, and FOLR2 expression were confirmed. Moreover, significantly diminished folic acid and S-adenosylmethionine levels were observed in parallel with decreasing 5-methylcytosine staining in tumours compared to normal adjacent to tumour tissues (p ≤ 0.05). CONCLUSION: Our results suggest that LINE-1 hypomethylation may have a distinguishing value in precancerous stages compared to healthy samples in liquid biopsies. Furthermore, the reduction of global DNA methylation level could be linked to reduced methyl-donor availability with the contribution of decreased FOLR2 expression.

Case Report: Development of Diffuse Large B Cell Lymphoma a Long Time After Hairy Cell Leukemia.

Hairy cell leukaemia (HCL) is a rare B cell malignancy with an indolent course leading to pancytopaenia due to bone marrow infiltration. It has been proposed that HCL patients are at risk of developing a secondary malignancy, with a marked likelihood of the development of other hematologic malignancies including Hodgkin lymphoma and high-grade non-Hodgkin lymphomas. Here, we present the case of two patients who developed diffuse large B cell lymphoma after a long course of hairy cell leukaemia. In the case of the female patient, we report on the occurrence of a third malignant disease, which is very uncommon. With our case descriptions we contribute to the very small number of similar cases reported.

Folic Acid Treatment Directly Influences the Genetic and Epigenetic Regulation along with the Associated Cellular Maintenance Processes of HT-29 and SW480 Colorectal Cancer Cell Lines.

Folic acid (FA) is a synthetic form of vitamin B9, generally used as a nutritional supplement and an adjunctive medication in cancer therapy. FA is involved in genetic and epigenetic regulation; therefore, it has a dual modulatory role in established neoplasms. We aimed to investigate the effect of short-term (72 h) FA supplementation on colorectal cancer; hence, HT-29 and SW480 cells were exposed to different FA concentrations (0, 100, 10,000 ng/mL). HT-29 cell proliferation and viability levels elevated after 100 ng/mL but decreased for 10,000 ng/mL FA. Additionally, a significant (p ≤ 0.05) improvement of genomic stability was detected in HT-29 cells with micronucleus scoring and comet assay. Conversely, the FA treatment did not alter these parameters in SW480 samples. RRBS results highlighted that DNA methylation changes were bidirectional in both cells, mainly affecting carcinogenesis-related pathways. Based on the microarray analysis, promoter methylation status was in accordance with FA-induced expression alterations of 27 genes. Our study demonstrates that the FA effect was highly dependent on the cell type, which can be attributed to the distinct molecular background and the different expression of proliferation- and DNA-repair-associated genes (YWHAZ, HES1, STAT3, CCL2). Moreover, new aspects of FA-regulated DNA methylation and consecutive gene expression were revealed.

A Liquid Biopsy-Based Approach for Monitoring Treatment Response in Post-Operative Colorectal Cancer Patients.

Monitoring the therapeutic response of colorectal cancer (CRC) patients is crucial to determine treatment strategies; therefore, we constructed a liquid biopsy-based approach for tracking tumor dynamics in non-metastatic (nmCRC) and metastatic (mCRC) patients (n = 55). Serial blood collections were performed during chemotherapy for measuring the amount and the global methylation pattern of cell-free DNA (cfDNA), the promoter methylation of SFRP2 and SDC2 genes, and the plasma homocysteine level. The average cfDNA amount was higher (p < 0.05) in nmCRC patients with recurrent cancer (30.4 ± 17.6 ng) and mCRC patients with progressive disease (PD) (44.3 ± 34.5 ng) compared to individuals with remission (13.2 ± 10.0 ng) or stable disease (12.5 ± 3.4 ng). More than 10% elevation of cfDNA from first to last sample collection was detected in all recurrent cases and 92% of PD patients, while a decrease was observed in most patients with remission. Global methylation level changes indicated a decline (75.5 ± 3.4% vs. 68.2 ± 8.4%), while the promoter methylation of SFRP2 and SDC2 and homocysteine level (10.9 ± 3.4 µmol/L vs. 13.7 ± 4.3 µmol/L) presented an increase in PD patients. In contrast, we found exact opposite changes in remission cases. Our study offers a more precise blood-based approach to monitor the treatment response to different chemotherapies than the currently used markers.

Effect of E2 and long control region polymorphisms on disease severity in human papillomavirus type 11 mediated mucosal disease: Protein modelling and functional analysis.

Interaction of the long control region (LCR) and the E2 protein of HPV11s was studied by in silico modelling and in vitro functional analysis. Genomes of HPV11s from fifteen (six known and nine novel) patients (two solitary papillomas, eleven respiratory papillomatoses of different severity, one condyloma acuminatum and one cervical atypia) were sequenced; E2 polymorphisms were analysed in silico by protein modelling. E2 and LCR variants were cloned into pcDNA3.1+ expression vector and into pALuc reporter vector, respectively, transfected to HEp2 cells alone or in different combinations and the luciferase activity was measured. In the E2, the ubiquitous polymorphism K308R caused stronger binding between the dimers but did not alter DNA binding; E2s with this polymorphism were significantly less efficient than the reference in promoting LCR activity. The unique polymorphism Q86K changed the negative surface charge of E2 (Q86) to positive (K86). The unique polymorphisms S245F and N247T in the hinge region disrupt a probable phosphorylation site in a RXXS motif targeted by protein kinase A and B, but do not affect directly the amino acids critical to nuclear transport. Both unique patterns partly restored the LCR activating potential disrupted by K308R. A unique E2/E4 ORF with a 58-bp deletion leading to a frameshift and an early stop codon resulted in a practically nonfunctional E2, and was associated with a papillomatosis with dysplasia. When testing existing LCR-E2 combinations, LCR with intrinsically lower enhancer capacity was only marginally activated by its E2 (R308 and the deletion mutant), and did not significantly exceed the activity of the reference LCR without E2. Combined with more potent LCRs associated with more severe disease, the activity was significantly higher, but still significantly lower than LCRs with reference E2. In summary, LCR-E2 interaction determined by their polymorphisms may explain, at least partly, differences in disease severity.

Inflammatory or malignant? Lessons from a cystic lateral neck lesion with a sudden onset / Gyulladás vagy daganat? Egy hirtelen jelentkezo lateralis cysticus nyaki terime tanulságai

Összefoglaló. A lateralis cysticus nyaki terimék két leggyakoribb oka a branchiogen cysta és a cysticus nyaki áttét. Az átfedo lokalizáció (a leggyakrabban a IIA nyaki régióban), a betegek életkora és az esetenként hirtelen kezdet alapján a két leggyakoribb ok differenciáldiagnózisa nagy kihívást jelenthet. Egy hirtelen fellépo fájdalmas, bal oldali nyaki duzzanattal, dysphagiával és lázzal jelentkezo 72 éves férfi esetét ismertetjük. A nyak komputertomográfiás vizsgálata egy 6 cm legnagyobb átméroju, vastag falú, többrekeszes cysticus terimét igazolt. Infektív branchiogen cysta lehetoségére gondolva az elváltozást eltávolítottuk. A szövettan azonban p16-pozitív laphámrákot igazolt. A primer tumort végül az ipsilateralis tonsilla palatina állományában sikerült azonosítani. A beteg definitív radioterápiában részesült, és 18 hónappal a diagnózis után tumormentes. A nyaki cystákon, az infektív nyaki cystákon és a cysticus metastasisokon kívül a humán papillómavírussal összefüggo szájgarati laphámrákok infektív cysticus vagy necroticus metastasisait is figyelembe kell venni a lateralis cysticus nyaki terimék differenciáldiagnózisában. Orv Hetil. 2020; 162(15): 595-600. Summary. Branchial cleft cysts and cystic neck metastases are the two most common causes of cystic lateral neck masses. Based on the overlapping location (neck level IIA), patient age at onset and the occasionally sudden onset, their differential diagnosis is challenging. We present a 72-year-old male presenting with a suddenly emerging painful, left-sided neck swelling, dysphagia and fever. Computed tomography showed a 6 cm thick-walled multicystic mass. With the suspected diagnosis of an infected branchial cleft cyst, the lesion was removed. Histology confirmed p16 positive squamous cell carcinoma. Primary tumor was identified in the ipsilateral palatine tonsil. Definive radiotherapy was performed and the patient is free of disease at the 18-month follow-up. Beyond pure and infected branchial cleft cysts and pure cystic metastases, infected cystic or necrotic metastasis of human papillomavirus associated oropharyngeal squamous cell carcinoma should be included in the differential diagnosis of cystic lateral neck lesions. Orv Hetil. 2021; 162(15): 595-600.

S-Adenosylmethionine Treatment of Colorectal Cancer Cell Lines Alters DNA Methylation, DNA Repair and Tumor Progression-Related Gene Expression.

Global DNA hypomethylation is a characteristic feature of colorectal carcinoma (CRC). The tumor inhibitory effect of S-adenosylmethionine (SAM) methyl donor has been described in certain cancers including CRC. However, the molecular impact of SAM treatment on CRC cell lines with distinct genetic features has not been evaluated comprehensively. HT-29 and SW480 cells were treated with 0.5 and 1 mmol/L SAM for 48 h followed by cell proliferation measurements, whole-genome transcriptome and methylome analyses, DNA stability assessments and exome sequencing. SAM reduced cell number and increased senescence by causing S phase arrest, besides, multiple EMT-related genes (e.g., TGFB1) were downregulated in both cell lines. Alteration in the global DNA methylation level was not observed, but certain methylation changes in gene promoters were detected. SAM-induced γ-H2AX elevation could be associated with activated DNA repair pathway showing upregulated gene expression (e.g., HUS1). Remarkable genomic stability elevation, namely, decreased micronucleus number and comet tail length was observed only in SW480 after treatment. SAM has the potential to induce senescence, DNA repair, genome stability and to reduce CRC progression. However, the different therapeutic responses of HT-29 and SW480 to SAM emphasize the importance of the molecular characterization of CRC cases prior to methyl donor supplementation.

Promoter Hypomethylation and Increased Expression of the Long Non-coding RNA LINC00152 Support Colorectal Carcinogenesis.

Up-regulation of the long non-coding RNA LINC00152 can contribute to cancer development, proliferation and invasion, including colorectal cancer, however, its mechanism of action in colorectal carcinogenesis and progression is only insufficiently understood. In this work we correlated LINC00152 expression with promoter DNA methylation changes in colorectal tissues along the normal-adenoma-carcinoma sequence and studied the effects of LINC00152 silencing on the cell cycle regulation and on the whole transcriptome in colon carcinoma cells using cell and molecular biology techniques. LINC00152 was significantly up-regulated in adenoma and colorectal cancer (p < 0.001) compared to normal samples, which was confirmed by real-time PCR and in situ hybridization. LINC00152 promoter hypomethylation detected in colorectal cancer (p < 0.01) was strongly correlated with increased LINC00152 expression (r=-0.90). Silencing of LINC00152 significantly suppressed cell growth, induced apoptosis and decreased cyclin D1 expression (p < 0.05). Whole transcriptome analysis of LINC00152-silenced cells revealed significant down-regulation of oncogenic and metastasis promoting genes (e.g. YES proto-oncogene 1, PORCN porcupine O-acyltransferase), and up-regulation of tumour suppressor genes (e.g. DKK1 dickkopf WNT signalling pathway inhibitor 1, PERP p53 apoptosis effector) (adjusted p < 0.05). Pathway analysis confirmed the LINC00152-related activation of oncogenic molecular pathways including those driven by PI3K/Akt, Ras, WNT, TP53, Notch and ErbB. Our results suggest that promoter hypomethylation related overexpression of LINC00152 can contribute to the pathogenesis of colorectal cancer by facilitating cell progression through the up-regulation of several oncogenic and metastasis promoting pathway elements.

[Potential role of estrogens in colorectal tumour development]. / Az ösztrogének lehetséges szerepe a vastagbéldaganatok kialakulásában.

Colorectal cancer (CRC) is one of the most common types of cancers worldwide. The incidence of sporadic CRC is lower in individuals below 50 years and increases with age, furthermore, it shows typical clinical, macroscopic and molecular differences between females and males. According to the results of epidemiological and molecular biology studies, the estradiol-regulating signaling pathway plays an important role in the development and prognosis of CRC, predominantly through estrogen receptor beta (ERß), which is dominant in the colonic epithelium. Estradiol has multiple gastrointestinal effects, which were confirmed by in vitro and in vivo studies on histologically intact and cancerous cells as well. In contrast to estrogen receptor alpha (ERα), the activation of ERß inhibits cell proliferation and enhances apoptosis, nevertheless, the expression of estrogen receptor beta can change both during physiological ageing and in colorectal disorders. The ERß-mediated antitumour effects of estradiol may be exerted through inhibition of cell proliferation, stimulation of apoptosis, inhibition of metastasis formation and its anti-inflammatory activity. Based on the results of cell culture and animal studies, selective modulators of estrogen receptor beta (selective estrogen receptor modulator [SERM]) and phytoestrogens can be new, additional therapeutic options in the treatment of colorectal diseases characterized by chronic inflammation and uncontrolled cell proliferation. Orv Hetil. 2020; 161(14): 532-543.