Wnt6 regulates the homeostasis of the stem cell niche via Rac1-and Cdc42-mediated noncanonical Wnt signalling pathways in Drosophila testis.

The homeostasis of the stem cell niche is regulated by both intrinsic and extrinsic factors, and the complex and ordered molecular and cellular regulatory mechanisms need to be further explored. In Drosophila testis, germline stem cells (GSCs) rely on hub cells for self-renewal and physical attachment. GSCs are also in contact with somatic cyst stem cells (CySCs). Utilizing genetic manipulation in Drosophila, we investigated the role of Wnt6 in vivo and in vitro. In Drosophila testis, we found that Wnt6 is required for GSC differentiation and CySC self-renewal. In Schneider 2 (S2) cells, we found that Wnt6 regulates cell proliferation and apoptosis. Mechanistically, we demonstrated that Wnt6 can downregulate the expression levels of Arm, Rac1 and Cdc42 in S2 cells. Notably, Rac1 and Cdc42, which act downstream of the noncanonical Wnt signalling pathway, imitated the phenotypes of Wnt6 in Drosophila testis. Thus, the newly discovered Wnt6-Rac1/Cdc42 signal axis is required for the homeostasis of the stem cell niche in the Drosophila testis.

LINGO family receptors are differentially expressed in the mouse brain and form native multimeric complexes.

Leucine-rich repeat and immunoglobin-domain containing (LRRIG) proteins that are commonly involved in protein-protein interactions play important roles in nervous system development and maintenance. LINGO-1, one of this family members, is characterized as a negative regulator of neuronal survival, axonal regeneration, and oligodendrocyte precursor cell (OPC) differentiation into mature myelinating oligodendrocytes. Three LINGO-1 homologs named LINGO-2, LINGO-3, and LINGO-4 have been described. However, their relative expression and functions remain unexplored. Here, we show by in situ hybridization and quantitative polymerase chain reaction that the transcripts of LINGO homologs are differentially expressed in the central nervous system. The immunostaining of brain slices confirmed this observation and showed the co-expression of LINGO-1 with its homologs. Using BRET (bioluminescence resonance energy transfer) analysis, we demonstrate that LINGO proteins can physically interact with each of the other ones with comparable affinities and thus form the oligomeric states. Furthermore, co-immunoprecipitation experiments indicate that LINGO proteins form heterocomplexes in both heterologous systems and cortical neurons. Since LINGO-1 is a promising target for the treatment of demyelinating diseases, its ability to form heteromeric complexes reveals a new level of complexity in its functioning and opens the way for new strategies to achieve diverse and nuanced LINGO-1 regulation.

Small ribonucleoprotein particle protein SmD3 governs the homeostasis of germline stem cells and the crosstalk between the spliceosome and ribosome signals in Drosophila.

The ribonucleoprotein (RNP) spliceosome machinery triggers the precursor RNA splicing process in eukaryotes. Major spliceosome defects are implicated in male infertility; however, the underlying mechanistic links between the spliceosome and the ribosome in Drosophila testes remains largely unresolved. Small ribonucleoprotein particle protein SmD3 (SmD3) is a novel germline stem cell (GSC) regulatory gene identified in our previous screen of Drosophila testes. In the present study, using genetic manipulation in a Drosophila model, we demonstrated that SmD3 is required for the GSC niche and controls the self-renewal and differentiation of GSCs in the testis. Using in vitro assays in Schneider 2 cells, we showed that SmD3 also regulates the homeostasis of proliferation and apoptosis in Drosophila. Furthermore, using liquid chromatography-tandem mass spectrometry methods, SmD3 was identified as binding with ribosomal protein (Rp)L18, which is a key regulator of the large subunit in the ribosome. Moreover, SmD3 was observed to regulate spliceosome and ribosome subunit expression levels and controlled spliceosome and ribosome function via RpL18. Significantly, our findings revealed the genetic causes and molecular mechanisms underlying the stem cell niche and the crosstalk between the spliceosome and the ribosome.-Yu, J., Luan, X., Yan, Y., Qiao, C., Liu, Y., Zhao, D., Xie, B., Zheng, Q., Wang, M., Chen, W., Shen, C., He, Z., Hu, X., Huang, X., Li, H., Chen, B., Zheng, B., Chen, X., Fang, J. Small ribonucleoprotein particle protein SmD3 governs the homeostasis of germline stem cells and the crosstalk between the spliceosome and ribosome signals in Drosophila.

Effects of N-acetylcysteine on CG8005 gene-mediated proliferation and apoptosis of Drosophila S2 embryonic cells.

To investigate the effect of the antioxidant N-acetylcysteine (NAC) on the proliferation and apoptosis in CG8005 gene-interfering Drosophila S2 embryonic cells by scavenging intracellular reactive oxygen species (ROS). The interfering efficiency of CG8005 gene in Drosophila S2 embryonic cells was verified by real-time quantitative PCR (qRT-PCR). Different concentrations of NAC and phosphate buffered saline (PBS) were used to affect the Drosophila S2 embryonic cells. The growth state of Drosophila S2 embryonic cells was observed by light microscope. Two probes dihydroethidium (DHE) and 2,7-dichlorodihydrofluorescein-acetoacetate (DCFH-DA) were used to observe the ROS production in each group after immunofluorescence staining. TUNEL staining and flow cytometry were used to investigate the apoptosis level of Drosophila S2 embryos, and CCK-8 (Cell Counting Kit-8) was used to detect the cell viability of Drosophila S2 embryos. The knockdown efficiency of siCG8005-2 fragment was high and stable, which was verified by interference efficiency (P < 0.05). There was no significant change in the growth of Drosophila S2 embryonic cells after the treatment of NAC as compared to PBS group. Moreover, knockdowning CG8005 gene resulted in an increase in ROS and apoptosis in Drosophila S2 embryonic cells (P < 0.05) and a decrease in proliferation activity (P < 0.05). In addition, the pretreatment of antioxidant NAC could inhibit ROS production in Drosophila S2 embryonic cells (P < 0.05), reduce cell apoptosis (P < 0.05), and improve cell survival (P < 0.05). The CG8005 gene in Drosophila S2 embryonic cells could regulate the proliferation and apoptosis of S2 embryonic cells by disrupting the redox homeostasis, and antioxidant NAC could inhibit cell apoptosis and promotes cell proliferation by scavenging ROS in Drosophila S2 embryonic cells, which is expected to provide novel insights for the pathogenesis of male infertility and spermatogenesis.

Combining Clinicopathologic and Ultrasonic Features for Predicting Skip Metastasis of Lateral Lymph Nodes in Papillary Thyroid Carcinoma.

Background: Skip metastasis, regarded as lateral lymph node metastasis (LLNM) without involving the central lymph node metastasis (CLNM), in papillary thyroid carcinoma (PTC) patients is commonly unpredictable. The purpose of the present research was to investigate the independent risk factors of skip metastasis in patients with PTC. Methods and Materials: In the present research, 228 consecutive PTC patients who experienced total thyroidectomy coupled with central and lateral lymph node dissection from May 2020 to September 2022 at the Affiliated hospital of Jiangsu University were included in our research. Univariate and multivariate analysis were then applied to investigate the risk factors of skip metastasis in patients with PTC. Furthermore, a predictive model of skip metastasis was then constructed based on risk factors. Results: The skip metastasis rate was 11.8% (27/228) in the current research. After the univariate and multivariate analysis, tumor size ≤ 10 mm, unilaterality, microcalcification, and upper tumor location were determined to be predictive factors of skip metastasis. The risk score of skip metastasis was calculated: risk score = 1.229 × (if tumor nodule ≤ 10mm) + 1.518 × (if unilaterality nodule) + 1.074 × (if microcalcification in nodule) + 2.332 × (if nodule in upper location). Conclusion: Tumor size ≤ 10 mm, unilaterality, microcalcification, and upper tumor location can increase the occurrence of skip metastasis in patients with PTC, which is expected to provide useful information to guide the suitable intraoperative window.

Expression of the Human Serotonin 5-HT7 Receptor Rescues Phenotype Profile and Restores Dysregulated Biomarkers in a Drosophila melanogaster Glioma Model.

Gliomas are the most common primary brain tumors in adults. Significant progress has been made in recent years in identifying the molecular alterations involved in gliomas. Among them, an amplification/overexpression of the EGFR (Epidermal Growth Factor Receptor) proto-oncogene and its associated signaling pathways have been widely described. However, current treatments remain ineffective for glioblastomas, the most severe forms. Thus, the identification of other pharmacological targets could open new therapeutic avenues. We used a glioma model in Drosophila melanogaster that results from the overexpression of constitutively active forms of EGFR and PI3K specifically in glial cells. We observed hyperproliferation of glial cells that leads to an increase in brain size and lethality at the third instar larval stage. After expression of the human serotonin 5-HT7 receptor in this glioma model, we observed a decrease in larval lethality associated with the presence of surviving adults and a return to a normal morphology of brain for some Drosophila. Those phenotypic changes are accompanied by the normalization of certain metabolic biomarkers measured by High-Resolution Magic Angle Spinning NMR (HR-MAS NMR). The 5-HT7R expression in glioma also restores some epigenetic modifications and characteristic markers of the signaling pathways associated with tumor growth. This study demonstrates the role of the serotonin 5-HT7 receptor as a tumor suppressor gene which is in agreement with transcriptomic analysis obtained on human glioblastomas.

Wheelchair-related accidents: relationship with wheelchair-using behavior in active community wheelchair users.

OBJECTIVE: To report the prevalence, mechanisms, self-perceived causes, consequences, and wheelchair-using behaviors associated with wheelchair-related accidents. DESIGN: A case-control study. SETTING: Community. PARTICIPANTS: A sample of experienced, community-dwelling, active manual and powered wheelchair users (N=95) recruited from a hospital assistive technology service center. INTERVENTIONS: Not applicable. MAIN OUTCOME MEASURES: Wheelchair-using behaviors, wheelchair-related accidents over a 3-year period, and the mechanisms and consequences of the accidents. RESULTS: Among the 95 participants, 52 (54.7%) reported at least 1 accident and 16 (16.8%) reported 2 or more accidents during the 3 years prior to the interview. A total of 74 accidents, were categorized into tips and falls (87.8%), accidental contact (6.8%), and dangerous operations (5.4%). A logistic regression found individuals who failed to maintain their wheelchairs regularly (odds ratio [OR]=11.28; 95% confidence interval [CI], 2.62-48.61) and used a wheelchair not prescribed by professionals (OR=4.31; 95% CI, 1.10-16.82) had significantly greater risks of accidents. In addition to the risk factor, lack of regular wheelchair maintenance, the Poisson regression corroborated the other risk factor, seat belts not used (incident rate ratio=2.14; 95% CI, 1.08-4.14), for wheelchair-related accidents. CONCLUSIONS: Wheelchair-related accidents are closely related to their wheelchair-using behaviors. Services including professional evaluation, repair, maintenance, and an educational program on proper wheelchair use may decrease the risks of wheelchair accidents.

Somatic CG6015 mediates cyst stem cell maintenance and germline stem cell differentiation via EGFR signaling in Drosophila testes.

Stem cell niche is regulated by intrinsic and extrinsic factors. In the Drosophila testis, cyst stem cells (CySCs) support the differentiation of germline stem cells (GSCs). However, the underlying mechanisms remain unclear. In this study, we found that somatic CG6015 is required for CySC maintenance and GSC differentiation in a Drosophila model. Knockdown of CG6015 in CySCs caused aberrant activation of dpERK in undifferentiated germ cells in the Drosophila testis, and disruption of key downstream targets of EGFR signaling (Dsor1 and rl) in CySCs results in a phenotype resembling that of CG6015 knockdown. CG6015, Dsor1, and rl are essential for the survival of Drosophila cell line Schneider 2 (S2) cells. Our data showed that somatic CG6015 regulates CySC maintenance and GSC differentiation via EGFR signaling, and inhibits aberrant activation of germline dpERK signals. These findings indicate regulatory mechanisms of stem cell niche homeostasis in the Drosophila testis.

Cross-cultural adaptation and validation of the Quebec User Evaluation of Satisfaction with Assistive Technology (QUEST 2.0): the development of the Taiwanese version.

OBJECTIVE: To develop and validate a cross-cultural version of the Quebec User Evaluation of Satisfaction with Assistive Technology (QUEST 2.0) for users of assistive technology devices in Taiwan. DESIGN: A cross-sectional survey. PROCEDURES: The standard cultural adaptation procedure was used for questionnaire translation and cultural item design. A field test was then conducted for item selection and psychometric properties testing. SUBJECTS: One hundred and five volunteer assistive device users in community. MAIN OUTCOME MEASURES: A questionnaire comprising 12 items of the QUEST 2.0 and 16 culture-specific items. RESULTS: One culture-specific item, 'Cost', was selected based on eight criteria and added to the QUEST 2.0 (12 items) to formulate the Taiwanese version of QUEST 2.0 (T-QUEST). The T-QUEST consisted of 13 items which were classified into two domains: device (8 items) and service (5 items). The internal consistencies of the device, service and total T-QUEST scores were 0.87, 0.84 and 0.90, respectively. The device, services and total T-QUEST scores achieved good test-retest stability (intraclass correlation coefficient (ICC) 0.90, 0.97, 0.95). Exploratory factor analysis revealed that T-QUEST had a two-factor structure for device and service in the construct of user satisfaction (53.42% of the variance explained). CONCLUSIONS: Users of assistive device in different culture may have different concerns regarding satisfaction. T-QUEST is the first published version of QUEST with culture-specific items added to the original translated items of QUEST 2.0. T-QUEST was a valid and reliable tool for measuring user satisfaction among Mandarin-speaking individuals using various kinds of assistive devices.

Excessive reactive oxygen species induce apoptosis via the APPL1-Nrf2/HO-1 antioxidant signalling pathway in trophoblasts with missed abortion.

AIMS: Previous evidence has demonstrated that oxidative stress is related to the pathogenesis of missed abortion (MA), but the specific mechanism remains obscure. The adaptor protein APPL1 is one of the differential proteins in chorionic trophoblasts. Thus, this study aimed to assess the potential influence of APPL1 on oxidative stress responses as well the possible molecular mechanisms involving in MA. MAIN METHODS: In the present study, the chorionic trophoblasts and the HTR-8/SVneo cell line were researched in vitro. Small interfering RNA (siRNA) was used to suppress the expression of APPL1. The fluorescent probes DHE and DCFH-DA were used to assess the intracellular reactive oxidative species (ROS). The activity of superoxide dismutase (SOD) was determined. Apoptosis was detected by TUNEL and flow cytometry. Cell viability was determined using Cell Counting Kit-8. Protein expression was detected by immunohistochemistry, western blotting, and reverse transcription-quantitative PCR. KEY FINDINGS: The application of oxidant in normal chorionic trophoblasts induced cell death and overproduction of ROS, which was consistent with MA. In addition, knockdown of APPL1 in HTR-8/SVneo cells resulted in increased ROS and apoptosis, which could be rescued by pretreatment with antioxidants. Mechanistically, we report that overproduction of ROS in trophoblasts and disturbed SOD, APPL1 and Nrf2/HO-1 antioxidant responses constitute important contributors to apoptosis. SIGNIFICANCE: Our results suggest that APPL1 has antioxidant properties that suppress oxidative stress and apoptosis via the Nrf2/HO-1 pathway. Moreover, antioxidant N-acetylcysteine (NAC) effectively restored the impaired antioxidative defense system elicited by excess ROS, as a potential therapeutic reagent for MA.

CG8005 Mediates Transit-Amplifying Spermatogonial Divisions via Oxidative Stress in Drosophila Testes.

The generation of reactive oxygen species (ROS) widely occurs in metabolic reactions and affects stem cell activity by participating in stem cell self-renewal. However, the mechanisms of transit-amplifying (TA) spermatogonial divisions mediated by oxidative stress are not fully understood. Through genetic manipulation of Drosophila testes, we demonstrated that CG8005 regulated TA spermatogonial divisions and redox homeostasis. Using in vitro approaches, we showed that the knockdown of CG8005 increased ROS levels in S2 cells; the induced ROS generation was inhibited by NAC and exacerbated by H2O2 pretreatments. Furthermore, the silencing of CG8005 increased the mRNA expression of oxidation-promoting factors Keap1, GstD1, and Mal-A6 and decreased the mRNA expression of antioxidant factors cnc, Gclm, maf-S, ND-42, and ND-75. We further investigated the functions of the antioxidant factor cnc, a key factor in the Keap1-cnc signaling pathway, and showed that cnc mimicked the phenotype of CG8005 in both Drosophila testes and S2 cells. Our results indicated that CG8005, together with cnc, controlled TA spermatogonial divisions by regulating oxidative stress in Drosophila.

RpS13 controls the homeostasis of germline stem cell niche through Rho1-mediated signals in the Drosophila testis.

OBJECTIVES: Stem cell niche regulated the renewal and differentiation of germline stem cells (GSCs) in Drosophila. Previously, we and others identified a series of genes encoding ribosomal proteins that may contribute to the self-renewal and differentiation of GSCs. However, the mechanisms that maintain and differentiate GSCs in their niches were not well understood. MATERIALS AND METHODS: Flies were used to generate tissue-specific gene knockdown. Small interfering RNAs were used to knockdown genes in S2 cells. qRT-PCR was used to examine the relative mRNA expression level. TUNEL staining or flow cytometry assays were used to detect cell survival. Immunofluorescence was used to determine protein localization and expression pattern. RESULTS: Herein, using a genetic manipulation approach, we investigated the role of ribosomal protein S13 (RpS13) in testes and S2 cells. We reported that RpS13 was required for the self-renewal and differentiation of GSCs. We also demonstrated that RpS13 regulated cell proliferation and apoptosis. Mechanistically, we showed that RpS13 regulated the expression of ribosome subunits and could moderate the expression of the Rho1, DE-cad and Arm proteins. Notably, Rho1 imitated the phenotype of RpS13 in both Drosophila testes and S2 cells, and recruited cell adhesions, which was mediated by the DE-cad and Arm proteins. CONCLUSION: These findings uncover a novel mechanism of RpS13 that mediates Rho1 signals in the stem cell niche of the Drosophila testis.

Srlp is crucial for the self-renewal and differentiation of germline stem cells via RpL6 signals in Drosophila testes.

Self-renewal and differentiation in germline stem cells (GSCs) are tightly regulated by the stem cell niche and via multiple approaches. In our previous study, we screened the novel GSC regulatory gene Srlp in Drosophila testes. However, the underlying mechanistic links between Srlp and the stem cell niche remain largely undetermined. Here, using genetic manipulation of the Drosophila model, we systematically analyze the function and mechanism of Srlp in vivo and in vitro. In Drosophila, Srlp is an essential gene that regulates the self-renewal and differentiation of GSCs in the testis. In the in vitro assay, Srlp is found to control the proliferation ability and cell death in S2 cells, which is consistent with the phenotype observed in Drosophila testis. Furthermore, results of the liquid chromatography-tandem mass spectrometry (LC-MS/MS) reveal that RpL6 binds to Srlp. Srlp also regulates the expression of spliceosome and ribosome subunits and controls spliceosome and ribosome function via RpL6 signals. Collectively, our findings uncover the genetic causes and molecular mechanisms underlying the stem cell niche. This study provides new insights for elucidating the pathogenic mechanism of male sterility and the formation of testicular germ cell tumor.

Precursor RNA processing 3 is required for male fertility, and germline stem cell self-renewal and differentiation via regulating spliceosome function in Drosophila testes.

The nuclear pre-mRNA spliceosome is a large complex containing five small nuclear ribonucleoprotein particles (snRNPs) and many splicing factors. Messenger RNAs (mRNAs) are generated from pre-mRNAs by the process of RNA splicing, which is conserved in eukaryotes. Precursor RNA processing 3 (Prp3) is a U4/U6-associated snRNP whose function remains largely unknown. In the present study, using genetic manipulation of a Drosophila melanogaster testis model, we demonstrated that Prp3 is essential for male fertility in Drosophila. Prp3 deficiency in germline stem cells (GSCs) and early cyst cells resulted in abnormal structure of testes and maintenance defects of GSCs and cyst stem cells. Knockdown of Prp3 in spermatogonia and early cyst cells mediated tumor formation caused by differentiation defects. Using an in vitro assay, knockdown of Prp3 decreased proliferation and increased cell death, and controlled the spliceosome function via regulating spliceosome subunits expression in Drosophila S2 cells. We also identified two other splicing factors in the Prp complex (Prp19 and Prp8), which mimicked the phenotype of Prp3 in the Drosophila stem cell niche. Our results revealed a significant role of precursor RNA processing factors in male testes, indicating that Prp3, a key spliceosome component in the Prp complex, is essential for male fertility, and germline stem cell self-renewal and differentiation, via regulating the spliceosome function in Drosophila testes.

Systematic re-analysis strategy of serum indices identifies alkaline phosphatase as a potential predictive factor for cervical cancer.

The aim of the present study was to identify predictive factors for cervical cancer (CC) progression using a multistage approach. The present study obtained data from 390 healthy women and 259 patients with cervical cancer between June 2012 and June 2017, and used a multiple stage re-analysis strategy for clinical detection of CC. A total of seven types of serum indices were used in the present study, including sugar chain antigen 125 (CA-125), sugar chain antigen 199 (CA-199), α fetoprotein (AFP), carcino- embryonic antigen, alkaline phosphatase (ALP), cholesterol and triglyceride (TG). The expression levels of CA-125, CA-199, AFP, ALP, cholesterol and TG were significantly different between healthy women and patients with cervical squamous cell carcinoma (SCC). Furthermore, ALP, cholesterol and TG expression levels were significantly different in healthy women compared with patients with cervical adenocarcinoma (AC). Further comparisons based on age and pathological staging demonstrated that the variability in the ALP level was not significant between the <40 years old age group and the 40-50 years old age group within healthy individuals (P>0.05); however, was significant in patients with SCC (P<0.05). Staging analysis identified significant differences in ALP between healthy women and patients with SCC (Stage I-IV), and significant differences between healthy women and patients with Stage I AC. The results of the present study indicated that the expression of ALP was significantly increased in patients with CC compared with healthy women. Therefore, ALP may be a potential predictive factor for the development of CC.

Biochemical clinical factors associated with missed abortion independent of maternal age: A retrospective study of 795 cases with missed abortion and 694 cases with normal pregnancy.

The incidence of fertile women with missed abortion dramatically increased in recent years, while very few serum indices have been identified for the diagnosis of missed abortion. The aim of this study was to identify related factors for missed abortion through a retrospective study of serum indices.A total of 795 cases of women with missed abortion and 694 cases of women with normal pregnancy between March 2014 and March 2017 were included in the present study. The diagnosis of missed abortion was based on clinical history, clinical examination, and transvaginal ultrasound findings. The final diagnosis of missed abortion was based on assessment of pregnancy structures (i.e., a gestational sac without fetal heart rate) via transvaginal ultrasound. We evaluated the clinical values of 4 serum indices and their relationship to missed abortion: gamma-glutamyltransferase (GGT), lactate dehydrogenase (LDH), adenosine deaminase (ADA), and fibrinogen (FIB).The serum levels of GGT, ADA, and FIB showed statistically significant differences comparing women who experienced missed abortion with women who had normal pregnancies (controls). Among women with missed abortion, the levels of GGT and ADA were dramatically increased (GGT: P < .0001; ADA: P = .0459), while FIB levels were slightly lower (P = .0084) compared to controls. The LDH levels exhibited a non-significant trend toward lower levels in the missed abortion group (P = .3951). Interestingly, the observed significant increase in serum GTT levels among women with missed abortion was not affected by maternal age.This study found that GTT may be a useful marker which was associated with missed abortion, indicating its potential clinical roles in missed abortion.

WNK1 kinase and its partners Akt, SGK1 and NBC-family Na+/HCO3- cotransporters are potential therapeutic targets for glioblastoma stem-like cells linked to Bisacodyl signaling.

Glioblastoma is a highly heterogeneous brain tumor. The presence of cancer cells with stem-like and tumor initiation/propagation properties contributes to poor prognosis. Glioblastoma cancer stem-like cells (GSC) reside in hypoxic and acidic niches favoring cell quiescence and drug resistance. A high throughput screening recently identified the laxative Bisacodyl as a cytotoxic compound targeting quiescent GSC placed in acidic microenvironments. Bisacodyl activity requires its hydrolysis into DDPM, its pharmacologically active derivative. Bisacodyl was further shown to induce tumor shrinking and increase survival in in vivo glioblastoma models. Here we explored the cellular mechanism underlying Bisacodyl cytotoxic effects using quiescent GSC in an acidic microenvironment and GSC-derived 3D macro-spheres. These spheres mimic many aspects of glioblastoma tumors in vivo, including hypoxic/acidic areas containing quiescent cells. Phosphokinase protein arrays combined with pharmacological and genetic modulation of signaling pathways point to the WNK1 serine/threonine protein kinase as a mediator of Bisacodyl cytotoxic effect in both cell models. WNK1 partners including the Akt and SGK1 protein kinases and NBC-family Na+/HCO3- cotransporters were shown to participate in the compound's effect on GSC. Overall, our findings uncover novel potential therapeutic targets for combatting glioblastoma which is presently an incurable disease.

Cancer Stem Cell Quiescence and Plasticity as Major Challenges in Cancer Therapy.

Cells with stem-like properties, tumorigenic potential, and treatment-resistant phenotypes have been identified in many human malignancies. Based on the properties they share with nonneoplastic stem cells or their ability to initiate and propagate tumors in vivo, such cells were designated as cancer stem (stem-like) or tumor initiating/propagating cells. Owing to their implication in treatment resistance, cancer stem cells (CSCs) have been the subject of intense investigation in past years. Comprehension of CSCs' intrinsic properties and mechanisms they develop to survive and even enhance their aggressive phenotype within the hostile conditions of the tumor microenvironment has reoriented therapeutic strategies to fight cancer. This report provides selected examples of malignancies in which the presence of CSCs has been evidenced and briefly discusses methods to identify, isolate, and functionally characterize the CSC subpopulation of cancer cells. Relevant biological targets in CSCs, their link to treatment resistance, proposed targeting strategies, and limitations of these approaches are presented. Two major aspects of CSC physiopathology, namely, relative in vivo quiescence and plasticity in response to microenvironmental cues or treatment, are highlighted. Implications of these findings in the context of the development of new therapies are discussed.

Indicators of perceived useful dementia care assistive technology: Caregivers' perspectives.

AIM: The study aims to investigate the caregivers' context-specific perceived usefulness of available assistive technology (AT) devices and the professionals' perspectives on the usefulness indicators of AT devices for home-dwelling individuals with mild-to-moderate dementia. METHODS: A total of 72 caregivers completed a questionnaire rating 82 AT devices with a high-perceived usefulness (HPU) or low-perceived usefulness (LPU). A total of 21 experts rated 10 usefulness indicators of these devices. We compared the mean of each indicator between the HPU and LPU groups. RESULTS: Most caregivers, who are generally amenable to using AT devices, thought they were useful for helping to care for home-dwelling older adults with mild-to-moderate dementia. The level of perceived usefulness from the experts' perspectives depends on specific design indicators (e.g. familiarity) and the context in which the AT is used (e.g. in everyday life or in emergencies). Indicators for HPU devices were: allows selective accident prevention, has an intuitive interface, is familiar, offers ease of use and simplifies activities. LPU devices featured client prompting. There were no significant differences between HPU and LPU devices with indicators of: is automated, informs caregiver, preserves privacy and preserves autonomy. Safety issues were considered important, and sometimes overshadowed ethical dilemmas, such as privacy and autonomy concern. CONCLUSIONS: The present study provides insight into how caregivers perceived the usefulness of AT devices, and how that varied with context. Indicators of devices perceived as useful can serve as guidelines for modifying existing devices and designing new devices. Future application could also incorporate the points of view from the persons with dementia.

Chemical Library Screening and Structure-Function Relationship Studies Identify Bisacodyl as a Potent and Selective Cytotoxic Agent Towards Quiescent Human Glioblastoma Tumor Stem-Like Cells.

Cancer stem-like cells reside in hypoxic and slightly acidic tumor niches. Such microenvironments favor more aggressive undifferentiated phenotypes and a slow growing "quiescent state" which preserves them from chemotherapeutic agents that essentially target proliferating cells. Our objective was to identify compounds active on glioblastoma stem-like cells, including under conditions that mimick those found in vivo within this most severe and incurable form of brain malignancy. We screened the Prestwick Library to identify cytotoxic compounds towards glioblastoma stem-like cells, either in a proliferating state or in more slow-growing "quiescent" phenotype resulting from non-renewal of the culture medium in vitro. Compound effects were assessed by ATP-level determination using a cell-based assay. Twenty active molecules belonging to different pharmacological classes have thus been identified. Among those, the stimulant laxative drug bisacodyl was the sole to inhibit in a potent and specific manner the survival of quiescent glioblastoma stem-like cells. Subsequent structure-function relationship studies led to identification of 4,4'-dihydroxydiphenyl-2-pyridyl-methane (DDPM), the deacetylated form of bisacodyl, as the pharmacophore. To our knowledge, bisacodyl is currently the only known compound targeting glioblastoma cancer stem-like cells in their quiescent, more resistant state. Due to its known non-toxicity in humans, bisacodyl appears as a new potential anti-tumor agent that may, in association with classical chemotherapeutic compounds, participate in tumor eradication.