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α-Actinins (ACTNs) are known to crosslink actin filaments at focal adhesions in migrating cells. Among the four isoforms of mammalian ACTNs, ACTN1 and ACTN4 are ubiquitously expressed. Recently, ACTN4 was reported to enhance cancer cell motility, invasion, and metastasis. However, the mechanism by which ACTN4 drives these malignant phenotypes remains unclear. Here, we show that ACTN4, but not ACTN1, induces the formation of immature focal adhesions in DLD-1 cells, leading to the rapid turnover of focal adhesions. Interestingly, zyxin (ZYX) assembly to focal adhesions was markedly decreased in ACTN4-expressing DLD-1 cells, while the recruitment of paxillin (PAX) occurred normally. On the other hand, in ACTN1-expressing DLD-1 cells, PAX and ZYX were normally recruited to focal adhesions, suggesting that ACTN4 specifically impairs focal adhesion maturation by inhibiting the recruitment of ZYX to focal complexes. Using purified recombinant proteins, we found that ZYX binding to ACTN4 was defective under conditions where ZYX binding to ACTN1 was observed. Furthermore, Matrigel invasion of SW480 cells that express high endogenous levels of ACTN4 protein was inhibited by ectopic expression of ACTN1. Altogether, our results suggest that ZYX defective binding to ACTN4, which occupies focal adhesions instead of ACTN1, induces the formation of immature focal adhesions, resulting in the enhancement of cell motility and invasion. [ABSTRACT FROM AUTHOR]

Nodal signaling induces the formation of the endoderm and mesoderm during gastrulation. Nodal expression persists until the definitive endoderm progenitor has completely formed, and disappears thereafter. A tightly regulated Nodal expression system is essential for the differentiation of embryonic stem (ES) cells into distinct tissue lineages. On this basis, we established an ES cell differentiation system with the tetracycline-regulated expression of Nodal. The upregulated Nodal signaling pathway and its downstream transcriptional targets induced the specification of ES cells into definitive endoderm and mesoderm derivatives, and the subsequent downregulation of Nodal signaling promoted further maturation of the gut tube both in vitro and in vivo. Sustained expression of the Nodal gene inhibited the maturation of the definitive endoderm owing to persistent Oct3 and/or Oct4 expression and teratoma formation. Furthermore, quantitative single cell analysis by flow cytometry using CXCR4, VEGFR2 and PDGFR-α indicated that this protocol for definitive endoderm and mesoderm differentiation is superior to any other available protocol. Our findings also indicated that the Nodal or Nodal-related molecules secreted from Nodal-expressing ES cells could cause genetically unmanipulated ES cells to induce the expression of the Nodal signaling pathway and its downstream targets, which consequently leads to the differentiation of the ES cells into definitive endoderm and mesoderm. Our differentiation system, using tightly regulated Nodal expression, enabled us to investigate the mechanism of ES cell differentiation into definitive endoderm or mesoderm derivatives. Our findings also demonstrate that Nodal-expressing ES cells might be a source of highly active proteins that could be used for developing endoderm or mesoderm tissues in regenerative medicine. [ABSTRACT FROM AUTHOR]

Aim: To test the hypothesis that hip fracture patients who receive occupational therapy (OT) have better functional ability than those who do not. Methods: This retrospective observational study utilized data from the Japan Rehabilitation Database spanning 2005–2015. In‐hospital hip fracture patients admitted to acute hospitals were identified. In total, 1266 patients were eligible based on the exclusion criteria. The primary outcome was motor Functional Independence Measure (FIM) efficiency. Results: Patients who received OT were 50.9% of hip fracture patients. Patients who received OT had significantly higher scores in motor FIM efficiency (mean 0.79 vs 0.70; P = 0.02) and FIM effectiveness (mean 0.49 vs 0.41; P < 0.01) than the patients who did not receive OT. From multivariate linear regression analysis, OT was identified as a significant factor in motor FIM efficiency (coefficient 1.29, 95% confidence interval 1.14–1.47; P < 0.01) and FIM effectiveness (coefficient 1.07, 95% confidence interval 1.02–1.12; P < 0.01). Conclusions: The present cohort analysis showed that OT for hip fracture patients in the acute phase likely contributes to improved functional ability. Geriatr Gerontol Int 2019; 19: 611–615. [ABSTRACT FROM AUTHOR]

Background Adjuvant therapy for colorectal cancer (CRC) in patients aged ≥75 years is supported by inadequate evidence, although such patients are increasing in number worldwide. Patients and methods We assessed the influence of age and comorbidities on the prognosis of CRC in elderly patients using pooled data by the Japanese Study Group for Postoperative Follow-up of Colorectal Cancer. In total, 4598 patients (3304 with colon cancer and 1294 with rectal cancer) who underwent curative surgery from 2004 to 2006 were analysed with respect to age, Charlson comorbidity score (CS), tumour marker positivity, adjuvant therapy and prognosis. Results The number of patients aged <64, 65–74 and >75 years was 2007 (44%), 1614 (35%) and 977 (21%), respectively. Tumour location, tumour marker positivity, clinical stage, performance of adjuvant therapy, CS and overall survival (OS) were significantly different among these age groups ( P < 0.0001). Among patients aged ≥75 years with stage III CRC, 35% with colon cancer and 21% with rectal cancer received adjuvant therapy; these proportions were much lower than those in younger patients. Application of adjuvant therapy was dependent on the CS in patients aged ≤74 years, but not in older patients. Sex, the carcinoembryonic antigen concentration and adjuvant therapy were significantly associated with OS in elderly patients with stage III CRC. Conclusion Age and comorbidities worsened the OS of patients with CRC who underwent curative surgery. However, patients aged ≥75 years were undertreated regardless of their CS despite the possibility of OS improvement by adjuvant therapy. [ABSTRACT FROM AUTHOR]