Liver-specific DICER1 syndrome model mice develop cystic liver tumors with defective primary cilia.

DICER1 syndrome is a tumor predisposition syndrome caused by familial genetic mutations in DICER1. Pathogenic variants of DICER1 have been discovered in many rare cancers, including cystic liver tumors. However, the molecular mechanisms underlying liver lesions induced by these variants remain unclear. In the present study, we sought to gain a better understanding of the pathogenesis of these variants by generating a mouse model of liver-specific DICER1 syndrome. The mouse model developed bile duct hyperplasia with fibrosis, similar to congenital hepatic fibrosis, as well as cystic liver tumors resembling those in Caroli's syndrome, intrahepatic cholangiocarcinoma, and hepatocellular carcinoma. Interestingly, the mouse model of DICER1 syndrome showed abnormal formation of primary cilia in the bile duct epithelium, which is a known cause of bile duct hyperplasia and cyst formation. These results indicated that DICER1 mutations contribute to cystic liver tumors by inducing defective primary cilia. The mouse model generated in this study will be useful for elucidating the potential mechanisms of tumorigenesis induced by DICER1 variants and for obtaining a comprehensive understanding of DICER1 syndrome. © 2024 The Pathological Society of Great Britain and Ireland.

Nuclear microRNAs release paused Pol II via the DDX21-CDK9 complex.

RNA activation (RNAa) is an uncharacterized mechanism of transcriptional activation mediated by small RNAs, such as microRNAs (miRNAs). A critical issue in RNAa research is that it is difficult to distinguish between changes in gene expression caused indirectly by post-transcriptional regulation and direct induction of gene expression by RNAa. Therefore, in this study, we seek to identify a key factor involved in RNAa, using the induction of ZMYND10 by miR-34a as a system to evaluate RNAa. We identify the positive transcription elongation factors CDK9 and DDX21, which form a complex with nuclear AGO and TNRC6A, as important transcriptional activators of RNAa. In addition, we find that inhibition of DDX21 suppresses RNAa by miR-34a and other miRNAs without inhibiting post-transcriptional regulation. Our findings reveal a strong connection between RNAa and release of paused Pol II, facilitating RNAa research by making it possible to separately analyze post-transcriptional regulation and RNAa.

Association of immune-related pneumonitis with clinical benefit of anti-programmed cell death-1 monotherapy in advanced non-small cell lung cancer.

BACKGROUND: The association between the development of checkpoint inhibitor pneumonitis (CIP) with tumor response and survival has remained unclear so far. The aim of the present study was to evaluate the association between CIP and the clinical efficacy of anti-programmed cell death-1 antibody in patients with advanced non-small cell lung cancer (NSCLC). METHODS: Between January 2016 and August 2019, 203 advanced NSCLC patients were administered with nivolumab or pembrolizumab. Comparisons were made between patients with and without CIP. We evaluated the time-to-treatment failure (TTF), progression-free survival (PFS), and overall survival (OS). RESULTS: CIP was observed in 28 (14%) patients. CIP was associated with a longer PFS (18.9 months [95% confidence interval, CI: 8.7 months-not reached] vs. 3.9 months [95% CI: 3.4-5.1 months, p < 0.01]) and longer OS (27.4 [95% CI: 20.7 months-not reached] vs. 14.8 months [95% CI: 11.2-17.9 months, p = 0.003]). Most patients discontinued the immune checkpoint inhibitor (ICI) treatment when they developed CIP. Seven patients (25%) lived for more than 300 days from treatment discontinuation and did not show any long-term tumor growth after treatment discontinuation. CONCLUSION: CIP was associated with prolonged PFS and OS. Additionally, 25% of CIP patients did not show any tumor growth for long periods after treatment discontinuation. Careful management of CIP can help in obtaining the best clinical efficacy from anti-PD-1 antibody.

Association Between Skin Reaction and Clinical Benefit in Patients Treated with Anti-Programmed Cell Death 1 Monotherapy for Advanced Non-Small Cell Lung Cancer.

BACKGROUND: Anti-programmed cell death 1 antibody is a standard therapy for advanced non-small cell lung cancer (NSCLC). However, immune-related adverse events (irAEs), such as skin reactions, are frequently observed. Although skin reactions are associated with clinical efficacy in melanoma, this association in advanced NSCLC and predictors of irAEs remain unclear. Accordingly, this study identified potential correlations of skin reactions with clinical efficacy and clinical predictors of development of skin reactions. SUBJECTS, MATERIALS, AND METHODS: We retrospectively surveyed patients with advanced NSCLC who received nivolumab or pembrolizumab monotherapy at Sendai Kousei Hospital (n = 155) during January 2016 to April 2018. Treatment efficacy was evaluated in patients with and without skin reactions, and associated predictive markers were determined. A 6-week landmark analysis was conducted to assess the clinical benefit of early skin reactions. RESULTS: Skin reactions were observed in 51 patients with a median time to onset of 6.4 weeks. The overall response rate (ORR) was significantly higher in patients with skin reactions (57% vs. 19%, p < .001). Median progression-free survival (PFS) durations of 12.9 and 3.5 months and overall survival durations of not reached and 11.4 months were observed in patients with and without skin reactions, respectively. In the 6-week landmark analysis, the ORR was significantly higher in patients with skin reactions, and skin reactions were significantly associated with increased PFS. A multivariate analysis identified pre-existing rheumatoid factor (RF) as an independent predictor of skin reactions. CONCLUSION: Skin reactions appeared beneficial in patients treated with nivolumab/pembrolizumab for advanced NSCLC and could be predicted by pre-existing RF. Further large-scale validations studies are warranted. IMPLICATIONS FOR PRACTICE: This single-institutional medical record review that included 155 patients with advanced non-small cell lung cancer who were treated with nivolumab or pembrolizumab monotherapy revealed that overall response rate and progression-free survival were significantly better in patients with skin reactions. Pre-existing rheumatoid factor was an independent predictor of skin reactions.

Intervention for the maintenance and improvement of physical function and quality of life among elderly disaster victims of the Great East Japan Earthquake and Tsunami.

PURPOSE: The purpose of this study was to examine the effectiveness of an exercise class implemented in an area affected by the Great East Japan Earthquake and Tsunami for maintaining and improving physical function and quality of life (QOL) among elderly victims. METHODS: Participants were 45 elderly disaster victims. To measure the effectiveness of the exercise classes, results on the Functional Reach Test (FRT), Timed Up and Go Test (TUG), One-leg Standing Balance (OSB), and Chair Stand Test (CST) were measured at the beginning of the exercise classes, and after 3 and 6months. In order to assess health-related QOL, the 8-item Short-Form Health Survey (SF-8) was carried out at the beginning of the exercise classes, and after 1, 3, and 6months. RESULTS: Of the 45 people who consented to participate, 27 continued the program for 6months and were used for analysis. Analysis of the results for FRT, OSB, and CST showed significant improvements (respectively, p=.000, .007, and .000). SF-8 showed significant increases for the subscales of bodily pain (p=.004), general health perception (p=.001), and mental health (p=.035). CONCLUSIONS: By continuing an exercise program for 6months, improvements were seen in lower limb muscle strength and balance functions. Effectiveness for HRQOL was also observed.

Genetic variation and population structure of the Japanese sika deer (Cervus nippon) in the Tohoku District based on mitochondrial D-loop sequences.

The sika deer (Cervus nippon) once inhabited the entire Tohoku District, the northeastern part of the main island of Japan. Currently, they are isolated as three discontinuous populations on Mt. Goyo, the Oshika Peninsula, and Kinkazan Island. To assess the genetic diversity and relationships among the sika deer populations in the Tohoku District, we analyzed the mitochondrial DNA D-loop sequences from 177 individuals. We detected a total of five haplotypes. Three haplotypes were present in the population from Mt. Goyo at a haplotype diversity of 0.235 ± 0.061, two haplotypes in the population from the Oshika Peninsula at 0.171 ± 0.064, and only one haplotype was detected in the population from the Kinkazan Island. A significant genetic differentiation was observed among all population pairs. Collectively, our data supports the observed population bottlenecks in the past. Four of the five haplotypes were specific to one of the three populations, whereas only one haplotype was shared between the Mt. Goyo and the Oshika Peninsula populations. This common haplotype may indicate a common ancestral population in the Tohoku District. Conversely, the D-loop haplotypes were completely different among the Kinkazan Island and Oshika Peninsula populations. The lack of a shared haplotype indicates that female gene flow between the two populations is very limited and that the 0.6 km strait acts as a strong barrier.