Distinct but interchangeable subpopulations of colorectal cancer cells with different growth fates and drug sensitivity

大腸がん細胞の増殖運命の違いと薬剤感受性 --その柔軟性を決めるメカニズム--. 京都大学プレスリリース. 2023-01-20.Dynamic changes in cell properties lead to intratumor heterogeneity; however, the mechanisms of nongenetic cellular plasticity remain elusive. When the fate of each cell from colorectal cancer organoids was tracked through a clonogenic growth assay, the cells showed a wide range of growth ability even within the clonal organoids, consisting of distinct subpopulations; the cells generating large spheroids and the cells generating small spheroids. The cells from the small spheroids generated only small spheroids (S-pattern), while the cells from the large spheroids generated both small and large spheroids (D-pattern), both of which were tumorigenic. Transition from the S-pattern to the D-pattern occurred by various extrinsic triggers, in which Notch signaling and Musashi-1 played a key role. The S-pattern spheroids were resistant to chemotherapy and transited to the D-pattern upon drug treatment through Notch signaling. As the transition is linked to the drug resistance, it can be a therapeutic target

A guiding role of the Arabidopsis circadian clock in cell differentiation revealed by time-series single-cell RNA sequencing

Circadian rhythms and progression of cell differentiation are closely coupled in multicellular organisms. However, whether establishment of circadian rhythms regulates cell differentiation or vice versa has not been elucidated due to technical limitations. Here, we exploit high cell fate plasticity of plant cells to perform single-cell RNA sequencing during the entire process of cell differentiation. By analyzing reconstructed actual time series of the differentiation processes at single-cell resolution using a method we developed (PeakMatch), we find that the expression profile of clock genes is changed prior to cell differentiation, including induction of the clock gene LUX ARRYTHMO (LUX). ChIP sequencing analysis reveals that LUX induction in early differentiating cells directly targets genes involved in cell-cycle progression to regulate cell differentiation. Taken together, these results not only reveal a guiding role of the plant circadian clock in cell differentiation but also provide an approach for time-series analysis at single-cell resolution

Effects of psychotherapy for middle-aged individuals with anxiety disorders in a general medicine practice

Background: Anxiety disorders are mental disorders that cause somatic symptoms for which patients may seek care from generalmedicine departments. We focused on anxiety disorders in middle-aged patients and examined the effect of a psychotherapeuticintervention.Materials and Methods: The participants were 14 middle-aged patients diagnosed with an anxiety disorder. Patients receivedpretreatment assessments and were randomly assigned to a pharmacotherapy group (n = 8) or a pharmacotherapy and psychotherapygroup (n = 6). The duration of the study was three months. Pre-and post-treatment, the Medical Outcomes Study 36-ItemShort-Form Health Survey (SF-36), State-Trait Anxiety Inventory (STAI), and a visual analog scale (VAS) were administered. Inthe pharmacotherapy and psychotherapy group, salivary cortisol was collected pre- and post-psychotherapy at the first and finalpsychotherapy sessions.Result: Four patients in the pharmacotherapy group withdrew from the study. There were no significant differences in the totalscores of the SF-36 or STAI between groups. Improvement was seen in the pharmacotherapy and psychotherapy group pre- andpost- treatment. SF-36 subscales of bodily pain (p = 0.02) and mental health (p = 0.04) were significantly higher than posttreatment.The state anxiety score on the STAI improved post-treatment (p = 0.03). On the VAS, the pharmacotherapy and psychotherapygroup’s symptoms were significantly improved (p = 0.02).Conclusion: This suggests that psychotherapy for middle-aged individuals contributes to the improvement of anxiety states andHRQoL in general medicine departments. It promotes the recognition of curative effects and prevents doctor shopping

Visceral fat obesity is the key risk factor for the development of reflux erosive esophagitis in 40–69-years subjects

[Background] Visceral fat obesity can be defined quantitatively by abdominal computed tomography, however, the usefulness of measuring visceral fat area to assess the etiology of gastrointestinal reflux disease has not been fully elucidated. [Methods] A total of 433 healthy subjects aged 40–69 years (234 men, 199 women) were included in the study. The relationship between obesity-related factors (total fat area, visceral fat area, subcutaneous fat area, waist circumference, and body mass index) and the incidence of reflux erosive esophagitis was investigated. Lifestyle factors and stomach conditions relevant to the onset of erosive esophagitis were also analyzed. [Results] The prevalence of reflux erosive esophagitis was 27.2% (118/433; 106 men, 12 women). Visceral fat area was higher in subjects with erosive esophagitis than in those without (116.6 cm2 vs. 64.9 cm2, respectively). The incidence of erosive esophagitis was higher in subjects with visceral fat obesity (visceral fat area ≥ 100 cm2) than in those without (61.2% vs. 12.8%, respectively). Visceral fat obesity had the highest odds ratio (OR) among obesity-related factors. Multivariate analysis showed that visceral fat area was associated with the incidence of erosive esophagitis (OR = 2.18), indicating that it is an independent risk factor for erosive esophagitis. In addition, daily alcohol intake (OR = 1.54), gastric atrophy open type (OR = 0.29), and never-smoking history (OR = 0.49) were also independently associated with the development of erosive esophagitis. [Conclusions] Visceral fat obesity is the key risk factor for the development of reflux erosive esophagitis in subjects aged 40–69 years

Relationship between somatic mosaicism of Pax6 mutation and variable developmental eye abnormalities : an analysis of CRISPR genome-edited mouse embryos

The clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein (Cas) system is a rapid gene-targeting technology that does not require embryonic stem cells. To demonstrate dosage effects of the Pax6 gene on eye formation, we generated Pax6-deficient mice with the CRISPR/Cas system. Eyes of founder embryos at embryonic day (E) 16.5 were examined and categorized according to macroscopic phenotype as class 1 (small eye with distinct pigmentation), class 2 (pigmentation without eye globes), or class 3 (no pigmentation and no eyes). Histologically, class 1 eyes were abnormally small in size with lens still attached to the cornea at E16.5. Class 2 eyes had no lens and distorted convoluted retinas. Class 3 eyes had only rudimentary optic vesicle-like tissues or histological anophthalmia. Genotyping of neck tissue cells from the founder embryos revealed somatic mosaicism and allelic complexity for Pax6. Relationships between eye phenotype and genotype were developed. The present results demonstrated that development of the lens from the surface ectoderm requires a higher gene dose of Pax6 than development of the retina from the optic vesicle. We further anticipate that mice with somatic mosaicism in a targeted gene generated by CRISPR/Cas-mediated genome editing will give some insights for understanding the complexity in human congenital diseases that occur in mosaic form

High-endothelial cell-derived s1p regulates dendritic cell localization and vascular integrity in the lymph node

While the sphingosine-1-phosphate (S1P)/sphingosine-1-phosphate receptor-1 (S1PR1) axis is critically important for lymphocyte egress from lymphoid organs, S1PR1-activation also occurs in vascular endothelial cells (ECs), including those of the high-endothelial venules (HEVs) that mediate lymphocyte immigration into lymph nodes (LNs). To understand the functional significance of the S1P/S1PR1-Gi axis in HEVs, we generated Lyve1;Spns2Δ/Δ conditional knockout mice for the S1P-transporter Spinster-homologue-2 (SPNS2), as HEVs express LYVE1 during development. In these mice HEVs appeared apoptotic and were severely impaired in function, morphology and size; leading to markedly hypotrophic peripheral LNs. Dendritic cells (DCs) were unable to interact with HEVs, which was also observed in Cdh5CRE-ERT2;S1pr1Δ/Δ mice and wildtype mice treated with S1PR1-antagonists. Wildtype HEVs treated with S1PR1-antagonists in vitro and Lyve1-deficient HEVs show severely reduced release of the DC-chemoattractant CCL21 in vivo. Together, our results reveal that EC-derived S1P warrants HEV-integrity through autocrine control of S1PR1-Gi signaling, and facilitates concomitant HEV-DC interactions.Simmons S., Sasaki N., Umemoto E., et al. High-endothelial cell-derived s1p regulates dendritic cell localization and vascular integrity in the lymph node. eLife 8, e41239 (2019); https://doi.org/10.7554/eLife.41239

Effects of smoking cessation on gastric emptying in smokers.

BACKGROUND: Smoking cessation can lead to changes in appetite and weight gain in some patients; thus, smoking cessation may alter gastrointestinal motility. Effects of smoking cessation on gastric emptying in smokers have not been established. AIM: This study sought to determine how smoking cessation affects gastric emptying in smokers. METHODS: Participant group comprised 53 habitual smokers and 12 healthy nonsmokers. Habitual smokers were treated for 2 months with transdermal nicotine patches. Gastric emptying was studied using C acetate breath tests at the beginning of the study, and at 1 week and 9 weeks after cessation of patch use. Maximal CO2 excretion time (Tmax), CO2 excretion half-life (T1/2), and parameters beta and kappa, representing initial and subsequent gastric-emptying phases, respectively, were determined using conventional formulae. RESULTS: Before smoking cessation, Tmax was reached significantly later in smokers (0.94+/-0.3 h, P=0.014) than in controls (0.89+/-0.1 h). At 1 week after the end of treatment, Tmax was significantly decreased (from 1.05+/-0.32 h to 0.72+/-0.64 h, P=0.003). T1/2 also tended to decrease, but not significantly. Although beta was decreased significantly (from 2.46+/-0.40 to 2.17+/-0.58, P=0.022), kappa was unchanged. However, by 9 weeks after the end of treatment, Tmax (1.28+/-0.69 h) had increased to levels seen before treatment. CONCLUSIONS: Smoking cessation temporarily accelerates gastric emptying, and decreases in beta suggest that initial-phase gastric emptying accelerates after smoking cessation. The temporary acceleration of gastric emptying after smoking cessation may be involved in the temporary increase in appetite and weight gain seen after smoking cessation