A modified MethyLight assay predicts the clinical outcomes of anti‐epidermal growth factor receptor treatment in metastatic colorectal cancer

DNA methylation status correlates with clinical outcomes of anti‐epidermal growth factor receptor (EGFR) treatment. There is a strong need to develop a simple assay for measuring DNA methylation status for the clinical application of drug selection based on it. In this study, we collected data from 186 patients with metastatic colorectal cancer (mCRC) who had previously received anti‐EGFR treatment. We modified MethyLite to develop a novel assay to classify patients as having highly methylated colorectal cancer (HMCC) or low‐methylated colorectal cancer (LMCC) based on the methylation status of 16 CpG sites of tumor‐derived genomic DNA in the development cohort (n = 30). Clinical outcomes were then compared between the HMCC and LMCC groups in the validation cohort (n = 156). The results showed that HMCC had a significantly worse response rate (4.2% vs 33.3%; P = .004), progression‐free survival (median: 2.5 vs 6.6 mo, P < .001, hazard ratio [HR] = 0.22), and overall survival (median: 5.6 vs 15.5 mo, P < .001, HR = 0.23) than did LMCC in patients with RAS wild‐type mCRC who were refractory or intolerable to oxaliplatin‐ and irinotecan‐based chemotherapy (n = 101). The DNA methylation status was an independent predictive factor and a more accurate biomarker than was the primary site of anti‐EGFR treatment. In conclusion, our novel DNA methylation measurement assay based on MethyLight was simple and useful, suggesting its implementation as a complementary diagnostic tool in a clinical setting.     

A questionnaire-based survey on the etiopathogenesis of chronic constipation during a medical check-up in Japan

The study group of the Japanese Society of Gastroenterology released evidence-based clinical practice guidelines for chronic constipation (CC) in 2017, and irritable bowel syndrome (IBS) was treated as one of the causes of CC. We examined the differences in characteristics between IBS and non-IBS subjects with CC who underwent a medical check-up in Japan. A total of 10,658 subjects participated in this study, and we focused on 467 subjects who fulfilled the diagnostic criteria of CC using a questionnaire survey. The number of IBS subjects was 21, and they had sleep disorders, were more symptomatic (e.g., abdominal pain, abdominal bloating/distension, feeling stressed, annoyance, lack of motivation, fatigue upon waking, and feeling depressed), and had more episodes of sensation of incomplete evacuation and anorectal obstruction/blockage during defecation than non-IBS subjects. Furthermore, stool frequency of IBS subjects was significantly different from non-IBS subjects. Multivariate ordinal logistic regression analysis revealed that the factors associated with a higher stool frequency were IBS [odds ratio (OR), 2.46; 95% confidence interval (CI), 1.00–6.05; p = 0.049], male sex (OR, 1.97; 95% CI, 1.20–3.23; p = 0.007), and regular exercise (OR, 1.80; 95% CI, 1.05–3.07; p = 0.033). These findings suggest that IBS has unique characteristics in subjects with CC.     

Heme oxygenase‐1: a new drug target in oxidative tissue injuries in critically ill conditions

Oxidative stresses associated with ischemia/reperfusion, neutrophil activation, and anesthesia with certain volatile agents, etc., are thought to play an important role in the development of acute organ failure in critical illnesses, such as acute lung injury, acute coronary artery insufficiency, acute liver failure, acute renal failure, and multiple organ dysfunction syndrome. Such oxidative stressors provoke a set of cellular responses, particularly those that participate in the defense against tissue injuries. Free heme, which can be rapidly released from hemeproteins, may constitute a major threat in the oxidant stress because it catalyzes the formation of reactive oxygen species. To counteract such insults, cells respond by inducing the 33‐kDa heat shock protein, heme oxygenase (HO)‐1, the rate‐limiting enzyme in heme degradation. Induced HO‐1 as such removes free heme by an enzymatic process. In addition, HO‐1 induction itself confers protection to tissues from further oxidative injuries. In contrast, the abrogation of HO‐1 induction, or chemical ablation of HO activity abolishes the beneficial effect of HO‐1, and results in the aggravation of tissue injuries. In this article, we review recent advances in the essential role of HO‐1 in tissue protection in various models of experimental oxidative tissue injuries as well as in human disorders, which is related to critically ill conditions, with special emphasis on the role of its induction in tissue defense and its potential therapeutic implications. Drug Dev. Res. 67:130–153, 2006. © 2006 Wiley‐Liss, Inc.     

Visualization of endothelial cell cycle dynamics in mouse using the Flt-1/eGFP-anillin system

Endothelial cell proliferation is a key process during vascular growth but its kinetics could only be assessed in vitro or ex vivo so far. To enable the monitoring and quantification of cell cycle kinetics in vivo, we have generated transgenic mice expressing an eGFP-anillin construct under control of the endothelial-specific Flt-1 promoter. This construct labels the nuclei of endothelial cells in late G1, S and G2 phase and changes its localization during the different stages of M phase, thereby enabling the monitoring of EC proliferation and cytokinesis. In Flt-1/eGFP-anillin mice, we found eGFP⁺ signals specifically in Ki67⁺/PECAM⁺ endothelial cells during vascular development. Quantification using this cell cycle reporter in embryos revealed a decline in endothelial cell proliferation between E9.5 to E12.5. By time-lapse microscopy, we determined the length of different cell cycle phases in embryonic endothelial cells in vivo and found a M phase duration of about 80 min with 2/3 covering karyokinesis and 1/3 cytokinesis. Thus, we have generated a versatile transgenic system for the accurate assessment of endothelial cell cycle dynamics in vitro and in vivo.     

Immunoglobulin G4-positive staining of orbital lesions in thyroid eye disease: Report of two cases

We report two cases with immunoglobulin G4 (IgG4)-positive staining of orbital lesions and thyroid eye disease (TED). Case 1 was a 63-year-old male with right upper eyelid swelling due to right lacrimal gland enlargement. Case 2 was a 49-year-old male with bilateral proptosis due to multiple orbital masses. Both the biopsied right lacrimal gland in Case 1 and the orbital masses on both sides in Case 2 showed infiltration of immunoglobulin-G4-positive plasma cells.