ABX464 (obefazimod) for moderate-to-severe, active ulcerative colitis: a phase 2b, double-blind, randomised, placebo-controlled induction trial and 48 week, open-label extension

BACKGROUND

ABX464 (obefazimod) is a small molecule that selectively upregulates miR-124 in immune cells. We aimed to assess ABX464 as a treatment for patients with moderate-to-severe, active ulcerative colitis.

METHODS

In this phase 2b, double-blind, randomised, placebo-controlled induction trial, patients were recruited from 95 centres (hospitals and health-care centres) in 16 countries. Eligible patients were aged 18-75 years, with a diagnosis of moderate-to-severe, active ulcerative colitis and a modified Mayo Score (MMS) of 5 points or higher, and a documented non-response or intolerance to previous treatment. Enrolled patients were randomly assigned (1:1:1:1) via an interactive voice and web response system to receive once daily oral ABX464 100 mg, ABX464 50 mg, ABX464 25 mg, or matched placebo. Randomisation was stratified according to study site (US vs non-US) and to whether the patient had previous exposure to second-line treatment with biologics or JAK inhibitors. The primary endpoint was the change from baseline in MMS at week 8. The primary efficacy analysis was done in the full analysis set (FAS), defined as all randomly assigned patients who received at least one dose of study treatment and had baseline data for at least one efficacy variable, and was analysed according to the principles of intention-to-treat. Safety analyses included patients who had been randomly assigned and who received at least one dose of study treatment. The 96 week open-label extension is ongoing. This study is registered with ClinicalTrials.gov, NCT04023396.

FINDINGS

Between Aug 13, 2019, and April 16, 2021, 254 patients were randomly allocated to ABX464 100 mg (n=64), ABX464 50 mg (n=63), ABX464 25 mg (n=63), or placebo (n=64). Two patients, both in the ABX464 25 mg group, were excluded from the FAS. In the FAS at week 8, the least squares mean (LSM) change from baseline in MMS was -2·9 (95% CI -3·4 to -2·5) for the ABX464 100 mg group, -3·2 (-3·7 to -2·7) for the ABX464 50 mg group, -3·1 (-3·6 to -2·6) for the ABX464 25 mg group, and -1·9 (-2·4 to -1·5) for placebo group; the magnitude of the difference in MMS from baseline was significantly greater in all three ABX464 groups compared with placebo (p=0·0039 for ABX464 100 mg vs placebo, p=0·0003 for ABX464 50 mg vs placebo, and p=0·0010 for ABX464 25 mg vs placebo). The most frequently reported adverse event was headache, which was reported for 27 (42%) of 64 patients in the ABX464 100 mg group, 19 (30%) of 63 in the 50 mg group, 13 (21%) of 62 in the 25 mg group, and five (8%) of 64 in the placebo group. Severe (grade 3) headache was reported for three (5%) patients in the ABX464 group 100 mg group, two (3%) in the ABX464 50 mg group, one (2%) in the ABX464 25 mg group, and none in the placebo group. The only serious adverse event reported for two or more patients in any group was ulcerative colitis (one in each of the ABX464 100 mg and 50 mg groups, and three [5%] in the placebo group).

INTERPRETATION

All doses of ABX464 significantly improved moderate-to-severe, active ulcerative colitis compared with placebo, as measured by changes in MMS from baseline to week 8. A phase 3 clinical programme is ongoing.

FUNDING

Abivax.

Small extracellular vesicle DNA-mediated horizontal gene transfer as a driving force for tumor evolution: Facts and riddles

The basis of the conventional gene-centric view on tumor evolution is that vertically inherited mutations largely define the properties of tumor cells. In recent years, however, accumulating evidence shows that both the tumor cells and their microenvironment may acquire external, non-vertically inherited genetic properties via horizontal gene transfer (HGT), particularly through small extracellular vesicles (sEVs). Many phases of sEV-mediated HGT have been described, such as DNA packaging into small vesicles, their release, uptake by recipient cells, and incorporation of sEV-DNA into the recipient genome to modify the phenotype and properties of cells. Recent techniques in sEV separation, genome sequencing and editing, as well as the identification of new secretion mechanisms, shed light on a number of additional details of this phenomenon. Here, we discuss the key features of this form of gene transfer and make an attempt to draw relevant conclusions on the contribution of HGT to tumor evolution.

Patai Á, Micsik T, Papp M, Márkus E, Tulassay Z, Igaz P, Takács I, Molnár B. 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.

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

Simple Summary

Folic acid (FA) participates in DNA synthesis and in DNA methylation; hence, it has a dual role in established neoplasms. We aimed to observe this phenomenon on FA-treated colorectal cancer cell lines (HT-29, SW480). Our results demonstrated that the maintenance processes, namely cell proliferation, cell viability, and DNA repair, were altered in HT-29 cells for short-term FA supplementation, while genetic and epigenetic regulations of SW480 cells were also affected. Despite the fact that FA is a precursor molecule in methyl donor formation, DNA methylation alterations were observed in both directions, primarily influencing the pathways of carcinogenesis. Moreover, behind the great number of differentially expressed genes, other FA-related effects than promoter methylation were suspected. All of our results point beyond the attributes related to FA so far. The different response of the two cell lines is worth considering in clinical practice to facilitate the effectiveness of therapy in the case of tumor heterogeneity.

Abstract

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.

Etrolizumab versus adalimumab or placebo as induction therapy for moderately to severely active ulcerative colitis (HIBISCUS): two phase 3 randomised, controlled trials

BACKGROUND

Etrolizumab is a gut-targeted anti-β7 integrin monoclonal antibody. In an earlier phase 2 induction study, etrolizumab significantly improved clinical remission relative to placebo in patients with moderately to severely active ulcerative colitis. The HIBISCUS studies aimed to compare the efficacy and safety of etrolizumab to adalimumab and placebo for induction of remission in patients with moderately to severely active ulcerative colitis.

METHODS

HIBISCUS I and HIBISCUS II were identically designed, multicentre, phase 3, randomised, double-blind, placebo-controlled and active-controlled studies of etrolizumab, adalimumab, and placebo in adult (18-80 years) patients with moderately to severely active ulcerative colitis (Mayo Clinic total score [MCS] of 6-12 with an endoscopic subscore of ≥2, a rectal bleeding subscore of ≥1, and a stool frequency subscore of ≥1) who were naive to tumour necrosis factor inhibitors. All patients had an established diagnosis of ulcerative colitis for at least 3 months, corroborated by both clinical and endoscopic evidence, and evidence of disease extending at least 20 cm from the anal verge. In both studies, patients were randomly assigned (2:2:1) to receive subcutaneous etrolizumab 105 mg once every 4 weeks; subcutaneous adalimumab 160 mg on day 1, 80 mg at week 2, and 40 mg at weeks 4, 6, and 8; or placebo. Randomisation was stratified by baseline concomitant treatment with corticosteroids, concomitant treatment with immunosuppressants, and baseline disease activity. All patients and study site personnel were masked to treatment assignment. The primary endpoint was induction of remission at week 10 (defined as MCS of 2 or lower, with individual subscores of 1 or lower, and rectal bleeding subscore of 0) with etrolizumab compared with placebo. Pooled analyses of both studies comparing etrolizumab and adalimumab were examined for several clinical and endoscopic endpoints. Efficacy was analysed using a modified intent-to-treat population, defined as all randomly assigned patients who received at least one dose of study drug. These trials are registered with ClinicalTrials.gov, NCT02163759 (HIBISCUS I), NCT02171429 (HIBISCUS II).

FINDINGS

Between Nov 4, 2014, and May 25, 2020, each study screened 652 patients (HIBISCUS I) and 613 patients (HIBISCUS II). Each study enrolled and randomly assigned 358 patients (HIBISCUS I etrolizumab n=144, adalimumab n=142, placebo n=72; HIBISCUS II etrolizumab n=143; adalimumab n=143; placebo n=72). In HIBISCUS I, 28 (19·4%) of 144 patients in the etrolizumab group and five (6·9%) of 72 patients in the placebo group were in remission at week 10, with an adjusted treatment difference of 12·3% (95% CI 1·6 to 20·6; p=0·017) in favour of etrolizumab. In HIBISCUS II, 26 (18·2%) of 143 patients in the etrolizumab group and eight (11·1%) of 72 patients in the placebo group were in remission at week 10, with an adjusted treatment difference of 7·2% (95% CI -3·8 to 16·1; p=0·17). In the pooled analysis, etrolizumab was not superior to adalimumab for induction of remission, endoscopic improvement, clinical response, histological remission, or endoscopic remission; however, similar numerical results were observed in both groups. In HIBISCUS I, 50 (35%) of 144 patients in the etrolizumab group reported any adverse event, compared with 61 (43%) of 142 in the adalimumab group and 26 (36%) of 72 in the placebo group. In HIBISCUS II, 63 (44%) of 143 patients in the etrolizumab group reported any adverse event, as did 62 (43%) of 143 in the adalimumab group and 33 (46%) in the placebo group. The most common adverse event in all groups was ulcerative colitis flare. The incidence of serious adverse events in the pooled patient population was similar for etrolizumab (15 [5%] of 287) and placebo (seven [5%] of 144) and lower for adalimumab (six [2%] of 285). Two patients in the etrolizumab group died; neither death was deemed to be treatment related.

INTERPRETATION

Etrolizumab was superior to placebo for induction of remission in HIBISCUS I, but not in HIBISCUS II. Etrolizumab was well tolerated in both studies.

FUNDING

F Hoffmann-La Roche.

Etrolizumab as induction and maintenance therapy for ulcerative colitis in patients previously treated with tumour necrosis factor inhibitors (HICKORY): a phase 3, randomised, controlled trial

BACKGROUND

Etrolizumab is a gut-targeted, anti-β7 integrin, monoclonal antibody. In an earlier phase 2 induction study, etrolizumab significantly improved clinical remission compared with placebo in patients with moderately to severely active ulcerative colitis. We aimed to evaluate the efficacy and safety of etrolizumab in patients with moderately to severely active ulcerative colitis who had been previously treated with anti-tumour necrosis factor (TNF) agents.

METHODS

HICKORY was a multicentre, phase 3, double-blind, placebo-controlled study in adult (18-80 years) patients with moderately to severely active ulcerative colitis (Mayo Clinic total score [MCS] of 6-12 with an endoscopic subscore of ≥2, a rectal bleeding subscore of ≥1, and a stool frequency subscore of ≥1) previously treated with TNF inhibitors. Patients were recruited from 184 treatment centres across 24 countries in North America, South America, Europe, Asia, Oceania, and the Middle East. Patients needed to have an established diagnosis of ulcerative colitis for at least 3 months, corroborated by both clinical and endoscopic evidence, and evidence of disease extending at least 20 cm from the anal verge. In cohort 1, patients received open-label etrolizumab 105 mg every 4 weeks for a 14-week induction period. In cohort 2, patients were randomly assigned (4:1) to receive subcutaneous etrolizumab 105 mg or placebo every 4 weeks for the 14-week induction phase. Patients in either cohort achieving clinical response to etrolizumab induction were eligible for the maintenance phase, in which they were randomly assigned (1:1) to receive subcutaneous etrolizumab 105 mg or placebo every 4 weeks through to week 66. Randomisation was stratified by baseline concomitant treatment with corticosteroids, concomitant treatment with immunosuppressants (induction randomisation only), baseline disease activity, week 14 MCS remission status (maintenance randomisation only), and induction cohort (maintenance randomisation only). All patients and study site personnel were masked to treatment assignment. Primary endpoints were remission (Mayo Clinic total score [MCS] ≤2, with individual subscores of ≤1 and a rectal bleeding subscore of 0) at week 14, and remission at week 66 among patients with a clinical response (MCS with ≥3-point decrease and ≥30% reduction from baseline, plus ≥1 point decrease in rectal bleeding subscore or absolute rectal bleeding score of 0 or 1) at week 14. Efficacy was analysed using a modified intent-to-treat population. Safety analyses included all patients who received at least one dose of study drug during the induction phase. This study is registered at ClinicalTrials.gov, NCT02100696.

FINDINGS

HICKORY was conducted from May 21, 2014, to April 16, 2020, during which time 1081 patients were screened, and 609 deemed eligible for inclusion. 130 patients were included in cohort 1. In cohort 2,479 patients were randomly assigned to the induction phase (etrolizumab n=384, placebo n=95). 232 patients were randomly assigned to the maintenance phase (etrolizumab to etrolizumab n=117, etrolizumab to placebo n=115). At week 14, 71 (18·5%) of 384 patients in the etrolizumab group and six (6·3%) of 95 patients in the placebo group achieved the primary induction endpoint of remission (p=0·0033). No significant difference between etrolizumab and placebo was observed for the primary maintenance endpoint of remission at week 66 among patients with a clinical response at week 14 (27 [24·1%] of 112 vs 23 [20·2%] of 114; p=0·50). Four patients in the etrolizumab group reported treatment-related adverse events leading to treatment discontinuation. The proportion of patients reporting at least adverse event was similar between treatment groups for induction (etrolizumab 253 [66%] of 384; placebo 63 [66%] of 95) and maintenance (etrolizumab to etrolizumab 98 [88%] of 112; etrolizumab to placebo 97 [85%] of 114). The most common adverse event in both groups was ulcerative colitis flare. Most adverse events were mild or moderate. During induction, the most common serious adverse event was ulcerative colitis flare (etrolizumab ten [3%] of 384; placebo: two [2%] of 95). During maintenance, the most common serious adverse event in the etrolizumab to etrolizumab group was appendicitis (two [2%] of 112) and the most common serious adverse events in the etrolizumab to placebo group were ulcerative colitis flare (two [2%] of 114) and anaemia (two [2%] of 114).

INTERPRETATION

HICKORY demonstrated that a significantly higher proportion of patients with moderately to severely active ulcerative colitis who had been previously treated with anti-TNF agent were able to achieve remission at week 14 when treated with etrolizumab compared with placebo; however, there was no significant difference between groups in remission at week 66 among patients with a clinical response at week 14.

FUNDING

F Hoffmann-La Roche.

Etrolizumab versus infliximab for the treatment of moderately to severely active ulcerative colitis (GARDENIA): a randomised, double-blind, double-dummy, phase 3 study

BACKGROUND

Etrolizumab is a gut-targeted anti-β7 integrin monoclonal antibody. In a previous phase 2 induction study, etrolizumab significantly improved clinical remission versus placebo in patients with moderately to severely active ulcerative colitis. We aimed to compare the safety and efficacy of etrolizumab with infliximab in patients with moderately to severely active ulcerative colitis.

METHODS

We conducted a randomised, double-blind, double-dummy, parallel-group, phase 3 study (GARDENIA) across 114 treatment centres worldwide. We included adults (age 18-80 years) with moderately to severely active ulcerative colitis (Mayo Clinic total score [MCS] of 6-12 with an endoscopic subscore of ≥2, a rectal bleeding subscore of ≥1, and a stool frequency subscore of ≥1) who were naive to tumour necrosis factor inhibitors. Patients were required to have had an established diagnosis of ulcerative colitis for at least 3 months, corroborated by both clinical and endoscopic evidence, and evidence of disease extending at least 20 cm from the anal verge. Participants were randomly assigned (1:1) to receive subcutaneous etrolizumab 105 mg once every 4 weeks or intravenous infliximab 5 mg/kg at 0, 2, and 6 weeks and every 8 weeks thereafter for 52 weeks. Randomisation was stratified by baseline concomitant treatment with corticosteroids, concomitant treatment with immunosuppressants, and baseline disease activity. All participants and study site personnel were masked to treatment assignment. The primary endpoint was the proportion of patients who had both clinical response at week 10 (MCS ≥3-point decrease and ≥30% reduction from baseline, plus ≥1-point decrease in rectal bleeding subscore or absolute rectal bleeding score of 0 or 1) and clinical remission at week 54 (MCS ≤2, with individual subscores ≤1); efficacy was analysed using a modified intention-to-treat population (all randomised patients who received at least one dose of study drug). GARDENIA was designed to show superiority of etrolizumab over infliximab for the primary endpoint. This trial is registered with ClinicalTrials.gov, NCT02136069, and is now closed to recruitment.

FINDINGS

Between Dec 24, 2014, and June 23, 2020, 730 patients were screened for eligibility and 397 were enrolled and randomly assigned to etrolizumab (n=199) or infliximab (n=198). 95 (48%) patients in the etrolizumab group and 103 (52%) in the infliximab group completed the study through week 54. At week 54, 37 (18·6%) of 199 patients in the etrolizumab group and 39 (19·7%) of 198 in the infliximab group met the primary endpoint (adjusted treatment difference -0·9% [95% CI -8·7 to 6·8]; p=0·81). The number of patients reporting one or more adverse events was similar between treatment groups (154 [77%] of 199 in the etrolizumab group and 151 [76%] of 198 in the infliximab group); the most common adverse event in both groups was ulcerative colitis (55 [28%] patients in the etrolizumab group and 43 [22%] in the infliximab group). More patients in the etrolizumab group reported serious adverse events (including serious infections) than did those in the infliximab group (32 [16%] vs 20 [10%]); the most common serious adverse event was ulcerative colitis (12 [6%] and 11 [6%]). There was one death during follow-up, in the infliximab group due to a pulmonary embolism, which was not considered to be related to study treatment.

INTERPRETATION

To our knowledge, this trial is the first phase 3 maintenance study in moderately to severely active ulcerative colitis to use infliximab as an active comparator. Although the study did not show statistical superiority for the primary endpoint, etrolizumab performed similarly to infliximab from a clinical viewpoint.

FUNDING

F Hoffmann-La Roche.

Controversials of Microscopic Colitis

Microscopic colitis (MC) has become a disease with increased awareness due to the availability of new data about the pathogenesis, diagnosis and therapy of this disease. The incidence of MC is increasing, reaching the incidence of the inflammatory bowel disease (IBD) in some populations. However, some aspects of MC are still controversial. It is unknown whether the changes of microbiome play a role in the pathogenesis and what is in the background of the different subtypes of disease that can transform into each other. Is there a connection between MC and IBD or why the histological changes do not follow the clinical activity? We do not know what the etiology of the incomplete MC is, and what its natural course is. The association of MC with celiac disease is well-known- is there a common pathogenesis? The MC treatment is budesonide. Its effectiveness is high, but the relapse rate is high, as well. Why would biologics be effective in these cases when budesonide is not? This mini-review makes an attempt to summarize the data about MC and highlight that there are still unanswered questions in the pathogenesis, diagnosis and therapy of the disease, which can initiate further investigations in the future.

The Behavior of MMP-2, MMP-7, MMP-9, and Their Inhibitors TIMP-1 and TIMP-2 in Adenoma-Colorectal Cancer Sequence

BACKGROUND

We and others have previously shown that matrix metalloproteinases (MMPs) play a role in colorectal cancer (CRC) invasion and metastasis. However, the serum changes of various MMPs and their inhibitors (TIMPs) have scarcely been concomitantly investigated in identical blood samples in the normal colon-adenoma-CRC sequence.

METHODS

The MMP-2, MMP-7, MMP-9, TIMP-1, and TIMP-2 serum antigen concentrations were determined concomitantly in 19 tumor-free control patients, 19 patients with high-risk colorectal adenoma, and 47 patients with CRC by ELISA technique. The analyzed parameters were also investigated in correlation with CRC stages. Statistical analysis with one-way ANOVA and Student's t test was performed. p values <0.05 were considered significant.

RESULTS

Serum antigen levels of MMPs and TIMPs were significantly increased in patients with CRC and adenomas compared to controls (mean values, ng/mL) (MMP-7: 5.88, 4.44, and 2.89, respectively, p = 0.001; MMP-9: 1,075.81, 999.22, and 845.97, respectively, p = 0.01; TIMP-1: 241.80, 205.98, and 166.53, respectively, p = 0.001; TIMP-2: 83.40, 80.30, and 69.62, respectively, p = 0.01). The elevated serum MMP-7, MMP-9, TIMP-1, and TIMP-2 levels significantly correlated with advanced tumor stages (p < 0.05). No statistically significant differences were observed in MMP-2 levels.

CONCLUSIONS

We demonstrate that serum antigen concentrations of MMP-7, MMP-9, TIMP-1, and TIMP-2 were significantly increased in patients with CRC and adenomas compared to controls. These results suggest that MMPs and their inhibitors TIMP-1 and TIMP-2 play an important role in CRC invasion; however, they are also activated in premalignant adenomas. Furthermore, MMP-7, MMP-9, TIMP-1, and TIMP-2 may have a potential prognostic impact in CRC.

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]

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 (ERβ), 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 ERβ inhibits cell proliferation and enhances apoptosis, nevertheless, the expression of estrogen receptor beta can change both during physiological ageing and in colorectal disorders. The ERβ-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.

Microscopic Colitis: A Challenging Disorder

BACKGROUND

The clinical importance of microscopic colitis (MC) is increasing. This is explained by both the increasing incidence and the challenges posed by the disease. However, recent MC data also reveal a number of doubts and uncertainties.

SUMMARY

This review focuses on current knowledge of MC and highlights the various controversies and criticisms regarding the clinical data about definitions, subtypes, pathogenesis, diagnosis, and treatment of this condition. Key Messages: The diagnosis of MC is based on histology, which distinguishes 2 subtypes. However, transitional forms often cause misclassification, which calls into question the reality (specificity, meaning) of the distinction between the 2 forms. The location of the colon biopsy is not defined by international consensus. There is no credible, clear explanation for the incidence increase. The pathogenesis is unknown, probably multifactorial, but the importance of the immunological background is increasing. The natural history of the disease and the underlying cause of relapses are unclear. It is suggested that MC would be the prelude of IBD. Further data collection is needed to clarify these issues.

Pharmacological Approach to Gastric Acid Suppression: Past, Present, and Future

Less than 2 centuries have elapsed since the identification of hydrochloric acid in the stomach. The clarification of the molecular mechanisms allowed the effective therapeutic suppression of gastric acid secretion. The spectacular advances in the treatment of acid-related disorders represent a synthesis of the contributions of several brilliant pharmacologists, basic scientists, and clinical physicians. Effective gastric acid suppressive therapy has dramatically improved the therapy and outcome of acid-related disorders. The introduction of proton pump inhibitors (PPIs) in clinical practice has significantly changed the medical management of upper gastrointestinal disorders. PPIs represent the "gold-standard" therapy in acid-related disorders. However, some challenges persist in the therapy of acid related diseases, including management of patients who respond inadequately to PPI therapy, more effective gastroprotection, or more powerful antisecretory treatment for the eradication of Helicobacter pylori infection. New antisecretory drugs are currently being developed and investigated to further provide a more effective and profound gastric acid secretion inhibition. The major advance has been the development of acid pump -antagonists, the potassium channel acid blocking drugs (-P-CABs). Long-term studies comparing P-CABs with PPIs will help to define the exact place and safety profile of this class of drug in the management of acid-related disorders.

Genome-wide expression profiling in colorectal cancer focusing on lncRNAs in the adenoma-carcinoma transition

Background

Long non-coding RNAs (lncRNAs) play a fundamental role in colorectal cancer (CRC) development, however, lncRNA expression profiles in CRC and its precancerous stages remain to be explored. We aimed to study whole genomic lncRNA expression patterns in colorectal adenoma–carcinoma transition and to analyze the underlying functional interactions of aberrantly expressed lncRNAs.

Methods

LncRNA expression levels of colonic biopsy samples (20 CRCs, 20 adenomas (Ad), 20 healthy controls (N)) were analyzed with Human Transcriptome Array (HTA) 2.0. Expression of a subset of candidates was verified by qRT-PCR and in situ hybridization (ISH) analyses. Furthermore, in silico validation was performed on an independent HTA 2.0, on HGU133Plus 2.0 array data and on the TCGA COAD dataset. MiRNA targets of lncRNAs were predicted with miRCODE and lncBase v2 algorithms and miRNA expression was analyzed on miRNA3.0 Array data. MiRNA-mRNA target prediction was performed using miRWALK and c-Met protein levels were analyzed by immunohistochemistry. Comprehensive lncRNA-mRNA-miRNA co-expression pattern analysis was also performed.

Results

Based on our HTA results, a subset of literature-based CRC-associated lncRNAs showed remarkable expression changes already in precancerous colonic lesions. In both Ad vs. normal and CRC vs. normal comparisons 16 lncRNAs, including downregulated LINC02023, MEG8, AC092834.1, and upregulated CCAT1, CASC19 were identified showing differential expression during early carcinogenesis that persisted until CRC formation (FDR-adjusted p < 0.05). The intersection of CRC vs. N and CRC vs. Ad comparisons defines lncRNAs characteristic of malignancy in colonic tumors, where significant downregulation of LINC01752 and overexpression of UCA1 and PCAT1 were found. Two candidates with the greatest increase in expression in the adenoma-carcinoma transition were further confirmed by qRT-PCR (UCA1, CCAT1) and by ISH (UCA1). In line with aberrant expression of certain lncRNAs in tumors, the expression of miRNA and mRNA targets showed systematic alterations. For example, UCA1 upregulation in CRC samples occurred in parallel with hsa-miR-1 downregulation, accompanied by c-Met target mRNA overexpression (p < 0.05).

Conclusion

The defined lncRNA sets may have a regulatory role in the colorectal adenoma-carcinoma transition. A subset of CRC-associated lncRNAs showed significantly differential expression in precancerous samples, raising the possibility of developing adenoma-specific markers for early detection of colonic lesions.

Modified Genomic Self-DNA Influences In Vitro Survival of HT29 Tumor Cells via TLR9- and Autophagy Signaling

In relation of immunobiology, the consequence of the crosstalk between TLR9-signaling and autophagy is poorly documented in HT29 cancer cells. To assess the TLR9-mediated biologic effects of modified self-DNA sequences on cell kinetics and autophagy response HT29 cells were incubated separately with intact genomic (g), hypermethylated (m), fragmented (f), and hypermethylated/fragmented (m/f) self-DNAs. Cell viability, apoptosis, cell proliferation, colonosphere-formation were determined. Moreover, the relation of TLR9-signaling to autophagy response was assayed by real-time RT-PCR, immunocytochemistry and transmission electron microscopy (TEM). After incubation with g-, m-, and m/f-DNAs cell viability and proliferation decreased, while apoptosis increased. F-DNA treatment resulted in an increase of cell survival. Methylation of self-DNA resulted in decrease of TLR9 expression, while it did not influence the positive effect of DNA fragmentation on MyD88 and TRAF6 overexpression, and TNFα downregulation. Fragmentation of DNA abrogated the positive effect of methylation on IRAK2, NFκB and IL-8 mRNA upregulations. In case of the autophagy genes and proteins, g- and f-DNAs caused significant upregulation of Beclin1, Atg16L1, and LC3B. According to TEM analyses, autophagy was present in each group of tumor cells, but to a varying degree. Incubation with m-DNA suppressed tumor cell survival by inducing features of apoptotic cell death, and activated mitophagy. F-DNA treatment enhanced cell survival, and activated macroautophagy and lipophagy. Colonospheres were only present after m-DNA incubation. Our data provided evidence for a close existing interplay between TLR9-signaling and the autophagy response with remarkable influences on cell survival in HT29 cells subjected to modified self-DNA treatments.

Diagnostic and prognostic potential of tissue and circulating long non-coding RNAs in colorectal tumors

Long non-coding RNAs (lncRNAs) are members of the non-protein coding RNA family longer than 200 nucleotides. They participate in the regulation of gene and protein expression influencing apoptosis, cell proliferation and immune responses, thereby playing a critical role in the development and progression of various cancers, including colorectal cancer (CRC). As CRC is one of the most frequently diagnosed malignancies worldwide with high mortality, its screening and early detection are crucial, so the identification of disease-specific biomarkers is necessary. LncRNAs are promising candidates as they are involved in carcinogenesis, and certain lncRNAs (e.g., CCAT1, CRNDE, CRCAL1-4) show altered expression in adenomas, making them potential early diagnostic markers. In addition to being useful as tissue-specific markers, analysis of circulating lncRNAs (e.g., CCAT1, CCAT2, BLACAT1, CRNDE, NEAT1, UCA1) in peripheral blood offers the possibility to establish minimally invasive, liquid biopsy-based diagnostic tests. This review article aims to describe the origin, structure, and functions of lncRNAs and to discuss their contribution to CRC development. Moreover, our purpose is to summarise lncRNAs showing altered expression levels during tumor formation in both colon tissue and plasma/serum samples and to demonstrate their clinical implications as diagnostic or prognostic biomarkers for CRC.

Analysis of microRNA expression in brush cytology specimens improves the diagnosis of pancreatobiliary cancer

BACKGROUND/OBJECTIVES

Malignant pancreatobiliary strictures are in many cases clinically indistinguishable and present a major problem to endoscopy specialists. Intraductal sampling procedures such as brush cytology are commonly used for diagnosis with a sensitivity that is low for a diagnostic test used in daily clinical practice. MicroRNA (miR) alterations detected in many cancers are disease-specific, which can be utilized in clinical applications. The aim of the present study was to analyze whether determination of miR expression levels in intraductal brush cytology specimens is a feasible approach to improve the diagnosis of pancreatobiliary cancer.

METHODS

Brush cytology specimens have been collected during endoscopic retrograde cholangio-pancreatography (ERCP) and analyzed by routine cytology and ancillary miR assays. Total RNA was extracted using the miRNeasy Mini Kit and the expression of miRs frequently dysregulated in pancreatobiliary cancer (miR-16, miR-21, miR-196a, miR-221) were analyzed by quantitative real-time PCR using RNU6B as internal control.

RESULTS

Routine cytology resulted in no false positive diagnoses, however, the combined sensitivity remained at 53.8%. Expression (ΔCt values) of miR-16 (p = 0.0039), miR-196a (p = 0.0003) and miR-221 (p = 0.0049) showed a clear statistical significance between malignant and benign pancreatobiliary specimens (n = 35). Malignancy could be detected combining routine cytology and the miR-196a single marker expression levels with a sensitivity of 84.6% (92.9% in biliary strictures) with no false positives.

CONCLUSIONS

The results offer the first direct demonstration that microRNAs are readily detectable in brush cytology specimens obtained during ERCP, and have the potential to help the cytological diagnosis of pancreatobiliary malignancy.

[Characteristics and diagnostic applications of circulating cell-free DNA in colorectal cancer]

The incidence and mortality of colorectal cancer (CRC) are considerably high in Central European countries, it is the second most common cancer in both men and women in Hungary with 10,000 newly registered patients per year. These data indicate the necessity of new screening methods that are more comfortable for patients, hence the compliance can be increased. Cell-free DNA (cfDNA) level in blood is elevated in certain physiological conditions, such as pregnancy or high physical activity. Furthermore, cfDNA concentration alterations can also be detected in some pathological processes; increased cfDNA amount was observed in autoimmune and inflammatory diseases, as well as in various cancers including CRC. Numerous studies about origin, function, and mechanism of cfDNA can be found in the scientific literature. In this review, we aimed to describe the quantitative and qualitative changes of cfDNA, to present its functions, and to provide an overview of the available diagnostic applications for CRC. CfDNA can be released to the circulatory system via apoptosis, necrosis or by direct secretions by living cells. In cancer patients, cfDNA can originate from healthy and cancer cells, hence genetic (e.g. mutations in APC, KRAS, BRAF) and epigenetic (e.g. methylation in SEPT9, SFRP1) alterations of tumor cells can be examined in cfDNA fraction. Several high-throughput, sensitive and even automated methods are available providing opportunity to perform standardized sample preparation and to analyse biomarker candidates quantitatively. These enhancements can help to develop alternative screening methods that can be easily integrated into the clinical practice and can contribute to early cancer detection. Orv Hetil. 2019; 160(30): 1167-1177.

[Physiological and pathophysiological significance of vitamin B9. Summary on the occasion of the 30-year introduction of folic acid as a dietary supplement]

Vitamin B9, also known as folate, can be found in natural and synthetic forms, mostly in vegetables or folic acid containing food supplements. By participating in the proper cell development and division, its presence is indispensable for certain basic metabolic processes. The decreased folate level of the body, mainly caused by environmental and hereditary factors as well as aging, can lead to genetic, epigenetic and metabolic changes. It can be related to the development of megaloblastic anemia, various cardiovascular diseases (such as atherosclerosis, stroke) obstetrical complications (such as abruption of the placentae, spontaneous abortion, preterm delivery, neural tube defect), neuropsychiatric diseases (such as Alzheimer's disease, Parkinson's disease, depression) and tumors. The vitamin has a preventive effect in all the above-mentioned diseases, however, in the case of tumor existence, its therapeutic use requires great care, as it may promote the progression of certain precancerous lesions. Food fortification with folic acid is currently being carried out in more than 60 countries in order to ensure a minimum vitamin B9 requirement for the population and therefore to prevent the development of the diseases that are connected to folic acid deficiency. Due to its assumable role in carcinogenesis, an initial concern had taken place when fortification was implemented (1998), however, the present statistical data do not confirm such adverse health effects. On the other hand, several beneficial properties can be connected to the vitamin, that can be the reason why more and more countries are considering to join this program. Besides the fact that folic acid is a widely used food supplement, it is also applied in oncological medicine (leucovorin) to increase the effectiveness of certain chemotherapeutical drugs (e.g. methotrexate, 5-fluorouracil). Orv Hetil. 2019; 160(28): 1087-1096.

Circulating cell-free nucleic acids as biomarkers in colorectal cancer screening and diagnosis - an update

Introduction: Screening methods for one of the most frequently diagnosed malignancy, colorectal cancer (CRC), have limitations. Circulating cell-free nucleic acids (cfNA) hold clinical relevance as screening, prognostic and therapy monitoring markers. Area covered: In this review, we summarize potential CRC-specific cfNA biomarkers, the recently developed sample preparation techniques, their applications, and pitfalls. Expert opinion: Automated extraction of cfDNA is highly reproducible, however, cfDNA yield is less compared to manual isolation. Quantitative and highly sensitive detection techniques (e.g. digital PCR, NGS) can be applied to analyze genetic and epigenetic changes. Detection of DNA mutations or methylation in cfDNA and related altered levels of mRNA, miRNA, and lncRNA may improve early cancer recognition, based on specific, CRC-related patterns. Detection of cfDNA mutations (e.g. TP53, KRAS, APC) has limited diagnostic sensitivity (40-60%), however, methylated DNA including SEPT9, SFRP1, SDC2 can be applied with higher sensitivity (up to 90%) for CRC. Circulating miRNAs (e.g. miR-21, miR-92, miR-141) provide comparably high sensitivity for CRC as the circulating tumor cell mRNA markers (e.g. EGFR, CK19, CK20, CEA). Automation of cfNA isolation coupled with quantitative analysis of CRC-related, highly sensitive biomarkers may enhance CRC screening and early detection in the future.

The Diagnosis and Therapy of Helicobacter pylori Infection in Hungary: Comparison of Strategies Applied by Family Physicians and Internists

BACKGROUND AIMS

Most patients with Helicobacter pylori infection are consulted for the first time by family physicians. We aimed to survey the adherence to the newest guidelines of the management of H. pylori infection in the primary and secondary care settings in Hungary.

METHODS

From a total of 793 physicians, 94 trainees in family medicine, 334 family physicians without and 195 with board certification in internal medicine, 87 internists, 78 family paediatricians were invited to take part in the study. Diagnostic and therapeutic attitudes towards H. pylori infection were compared by a voluntary and anonymous questionnaire.

RESULTS

Participants test for H. pylori infection in 92.8% of cases with a family history of peptic ulcer or 76.9% of gastric cancer, 68.9% of dyspepsia and 49.9% of non-specific abdominal complaints, before initiation of non-steroidal anti-inflammatory drug (NSAID; 17.3%) and antiplatelet treatment (14.5%), respectively. They confirm the success of eradication therapy in 88.1% mainly by urea breath test. Most of them initiate eradication therapy by themselves and only 22.4% refer their patients to a gastroenterologist. Clarithromycin-based standard triple therapy is the most preferred (62.1%) and only 3.7% choose quadruple combination with bismuth as first-line and 48.1% as second-line therapy. We found significant differences between groups with respect to the physicians' own infection, localization of practice, and sources of information on H. pylori infection. Internists are more likely to clarify H. pylori status before the initiation of NSAID and antiplatelet therapies, initiate second-line therapies and use bismuth compared to the other groups. Family physicians with board certification in internal medicine are also prone to start eradication therapy and less prone to refer patients to a gastroenterologist. Family paediatricians prefer stool antigen determination, screen family members and prefer gastroenterologist consultation more often, and use bismuth less frequently than the other groups. Family physicians with previous infection check for H. pyloriinfection more frequently before the initiation of NSAID treatment and are more likely to use histology to detect H. pylori. Postgraduate trainings were the most popular source of information.

CONCLUSION

The adherence to the recent recommendations of current guidelines is moderate. There is a need to increase adherence to current recommendations by family physicians and internists.

En bloc release of MVB-like small extracellular vesicle clusters by colorectal carcinoma cells

Small extracellular vesicles (EVs) are membrane enclosed structures that are usually released from cells upon exocytosis of multivesicular bodies (MVBs) as a collection of separate, free EVs. In this study, we analysed paraffin embedded sections of archived human colorectal cancer samples. We studied 3D reconstructions of confocal microscopic images complemented by HyVolution and STED imaging. Unexpectedly, we found evidence that large, MVB-like aggregates of ALIX/CD63 positive EV clusters were released en bloc by migrating tumour cells. These structures were often captured with partial or complete extra-cytoplasmic localization at the interface of the plasma membrane of the tumour cell and the stroma. Their diameter ranged between 0.62 and 1.94 μm (mean±S.D.: 1.17 ± 0.34 μm). High-resolution 3D reconstruction showed that these extracellular MVB-like EV clusters were composed of distinguishable internal particles of small EV size (mean±S.D.: 128.96 ± 16.73 nm). In vitro, HT29 colorectal cancer cells also showed the release of similar structures as confirmed by immunohistochemistry and immune electron microscopy. Our results provide evidence for an en bloc transmission of MVB-like EV clusters through the plasma membrane. Immunofluorescent-based detection of the MVB like small EV clusters in archived pathological samples may represent a novel and unique opportunity which enables analysis of EV release in situ in human tissues.

Efficacy and Safety of Budesonide, vs Mesalazine or Placebo, as Induction Therapy for Lymphocytic Colitis

BACKGROUND & AIMS

Lymphocytic colitis is a common cause of chronic, nonbloody diarrhea. However, the effects of treatment are unclear and randomized placebo-controlled trials were requested in a Cochrane review. We performed a randomized, placebo-controlled, multicenter study to evaluate budesonide and mesalazine as induction therapy for lymphocytic colitis.

METHODS

Patients with active lymphocytic colitis were randomly assigned to groups given budesonide 9 mg once daily (Budenofalk granules), mesalazine 3 g once daily (Salofalk granules), or placebo for 8 weeks in a double-blind, double-dummy design. The primary endpoint was clinical remission, defined as ≤21 stools (including ≤6 watery stools), in the 7 days before week 8.

RESULTS

The final analysis included 57 patients (19 per group). Most patients were female (72%) and the mean age was 59 years. The proportion of patients in clinical remission at week 8 was significantly higher in the budesonide group than in the placebo group (intention-to-treat analysis, 79% vs 42%; P = .01). The difference in proportions of patients in clinical remission at week 8 between the mesalazine (63%) and placebo groups was not significant (P = .09). The proportion of patients with histologic remission at week 8 was significantly higher in the budesonide group (68%) vs the mesalazine (26%; P = .02) or placebo (21%; P = .008) groups. The incidence of adverse events was 47.4% in the budesonide group, 68.4% in the mesalazine group, and 42.1% in the placebo group.

CONCLUSIONS

In a randomized multicenter study, we found oral budesonide 9 mg once daily to be effective and safe for induction of clinical and histologic remission in patients with lymphocytic colitis, compared with placebo. Oral mesalazine 3 g once daily was not significantly better than placebo. ClinicalTrials.gov no: NCT01209208.