Pancreatic RECK inactivation promotes cancer formation, epithelial-mesenchymal transition, and metastasis

膵癌悪性化の分子機構解明 --RECK発現の低下が膵癌の浸潤・転移を引き起こす--. 京都大学プレスリリース. 2023-09-19.RECK is downregulated in various human cancers; however, how RECK inactivation affects carcinogenesis remains unclear. We addressed this issue in a pancreatic ductal adenocarcinoma (PDAC) mouse model and found that pancreatic Reck deletion dramatically augmented the spontaneous development of PDAC with a mesenchymal phenotype, which was accompanied by increased liver metastases and decreased survival. Lineage tracing revealed that pancreatic Reck deletion induced epithelial-mesenchymal transition (EMT) in PDAC cells, giving rise to inflammatory cancer-associated fibroblast–like cells in mice. Splenic transplantation of Reck-null PDAC cells resulted in numerous liver metastases with a mesenchymal phenotype, whereas reexpression of RECK markedly reduced metastases and changed the PDAC tumor phenotype into an epithelial one. Consistently, low RECK expression correlated with low E-cadherin expression, poor differentiation, metastasis, and poor prognosis in human PDAC. RECK reexpression in the PDAC cells was found to downregulate MMP2 and MMP3, with a concomitant increase in E-cadherin and decrease in EMT-promoting transcription factors. An MMP inhibitor recapitulated the effects of RECK on the expression of E-cadherin and EMT-promoting transcription factors and invasive activity. These results establish the authenticity of RECK as a pancreatic tumor suppressor, provide insights into its underlying mechanisms, and support the idea that RECK could be an important therapeutic effector against human PDAC

Epithelial EP4 plays an essential role in maintaining homeostasis in colon

Colonic epithelial cells comprise the mucosal barrier, and their dysfunction promotes microbial invasion from the gut lumen and induces the development of intestinal inflammation. The EP4 receptor is known to mediate the protective effect of prostaglandin (PG) E2 in the gastrointestinal tract; however, the exact role of epithelial EP4 in intestinal pathophysiology remains unknown. In the present study, we aimed to investigate the role of epithelial EP4 in maintaining colonic homeostasis by characterizing the intestinal epithelial cell-specific EP4 knockout (EP4 cKO) mice. Mice harboring the epithelial EP4 deletion showed significantly lower colonic crypt depth and lower numbers of secretory cell lineages, as well as impaired epithelial cells in the colon. Interestingly, EP4-deficient colon epithelia showed a higher number of apoptotic cells. Consistent with the defect in mucosal barrier function of colonic epithelia and secretory cell lineages, EP4 cKO colon stroma showed enhanced immune cell infiltration, which was accompanied by increased production of inflammatory cytokines. Furthermore, EP4-deficient colons were susceptible to dextran sulfate sodium (DSS)-induced colitis. Our study is the first to demonstrate that epithelial EP4 loss resulted in potential "inflammatory" status under physiological conditions. These findings provided insights into the crucial role of epithelial PGE2/EP4 axis in maintaining intestinal homeostasis

Changes in Antipsychotic Medication in Clients of Assertive Community Treatment in Japan: A One-Year Follow Up

The purpose of the present one-year follow-up study was to describe and investigate the change in the amount of antipsychotic drugs prescribed for ACT (assertive community treatment) clients in Japan. Subjects were 52 clients of ACT from January 2009 to December 2009. Prescription data were collected each month from the time the clients entered into ACT. The results of a Wilcoxon signed-rank test show that the dosage of antipsychotics significantly decreased from 1,131.3 mg to 731.3 mg over the course of the 12 months (Z = -2.505, p = 0.012)

JNK pathway plays a critical role for expansion of human colorectal cancer in the context of BRG1 suppression

Tumor stem cells (TSCs), capable of self-renewal and continuous production of progeny cells, could be potential therapeutic targets. We have recently reported that chromatin remodeling regulator Brg1 is required for maintenance of murine intestinal TSCs and stemness feature of human colorectal cancer (CRC) cells by inhibiting apoptosis. However, it is still unclear how BRG1 suppression changes the underlying intracellular mechanisms of human CRC cells. We found that Brg1 suppression resulted in upregulation of the JNK signaling pathway in human CRC cells and murine intestinal TSCs. Simultaneous suppression of BRG1 and the JNK pathway, either by pharmacological inhibition or silencing of c-JUN, resulted in even stronger inhibition of the expansion of human CRC cells compared to Brg1 suppression alone. Consistently, high c-JUN expression correlated with worse prognosis for survival in human CRC patients with low BRG1 expression. Therefore, the JNK pathway plays a critical role for expansion and stemness of human CRC cells in the context of BRG1 suppression, and thus a combined blockade of BRG1 and the JNK pathway could be a novel therapeutic approach against human CRC

Final Results of Cilostazol-Aspirin Therapy against Recurrent Stroke with Intracranial Artery Stenosis (CATHARSIS)

Purpose: To compare the effect of cilostazol plus aspirin versus aspirin alone on the progression of intracranial arterial stenosis (IAS), and to compare ischemic and hemorrhagic events in patients with symptomatic IAS, an investigator-driven, nationwide multicenter cooperative randomized controlled trial (CATHARSIS; ClinicalTrials.gov Identifier 00333164) was conducted. Methods: 165 noncardioembolic ischemic stroke patients with >50% stenosis in the responsible intracranial artery after 2 weeks to 6 months from the onset were randomly allocated to receive either cilostazol 200 mg/day plus aspirin 100 mg/day (n = 83, CA group) or aspirin 100 mg/day alone (n = 82, A group). The primary endpoint was the progression of IAS on magnetic resonance angiography at 2 years after randomization. Secondary endpoints were any vascular events, any cause of death, serious adverse events, new silent brain infarcts, and worsening of the modified Rankin Scale score. Results: Progression of IAS was observed in 9.6% of the CA group patients and in 5.6% of the A group patients, with no significant intergroup difference (p = 0.53). The incidence of the secondary endpoints tended to be lower in the CA group compared with the A group, although the differences were not significant. By using exploratory logistic regression analysis adjusted for patient background characteristics, it was shown that the risk for certain combinations of secondary endpoints was lower in the CA group than in the A group [all vascular events and silent brain infarcts: odds ratio (OR) = 0.37, p = 0.04; stroke and silent brain infarcts: OR = 0.34, p = 0.04; all vascular events, worsening of modified Rankin Scale scores and silent brain infracts: OR = 0.41, p = 0.03]. Major hemorrhage was observed in 4 patients of the CA group and in 3 of the A group. Conclusion: Progression of IAS during the 2-year observation period appears to be less frequent than previously reported in stroke patients on antiplatelet agents after the acute phase, which could be due to the adequate control of risk factors, and because patients with stroke within 2 weeks after the onset were excluded. The results of the CATHARSIS trial suggest a potential utility of pharmacotherapies with cilostazol plus aspirin as well as of strict control of risk factors for the management of symptomatic IAS. Larger studies with higher statistical power are required to obtain conclusive results