The inhibitory effects of NKX3.1 on IGF- 1R expression and its signalling pathway in human prostatic carcinoma PC3 cells

NKX3.1, which is a prostate-specific homeobox gene, plays an important role in prostate cancer and usually functions as a tumour suppressor gene. In this study, we investigated the inhibitory effect of NKX3,1 on insulin-like growth factor （IGF）- 1R expression and its downstream signalling pathway in PC3 cells, PC3 cells were stably transfected with NKX3.1 expression plasmid （pcDNA3.1-NKX3.1） or vector plasmid （pcDNA3.1＋）. The IGF-IR mRNA and protein expression levels were assessed in PC3-NKX3.1 transfectants by reverse transcriptase-polymerase chain reaction （RT-PCR） and Western blotting. The expression and activation of IGF-1/IGF-1R downstream signalling targets were examined by Western blotting and luciferase reporter assay. The cells were subsequently treated with relevant concentrations of IGF-1. The effect of IGF-1 on cell growth was examined by 3-（4,5）-dimethylthiahiazo（-z-yl）-3, 5-diphenytetrazoliumromide （MTT） assay and flow cytometry analysis. A significant suppression of IGF-1R mRNA and protein expression was observed after forced expression of NKX3.1 in PC3 cells. Correspondingly, the forced expression of NKX3.1 decreased IGF-l-induced phosphorylation of extracellular signal-regulated kinase 1/2 （ERK1/2） and protein kinase B （AKT） and activation of the Elk-1 transcription factor and downregulated the expression of the downstream target genes c-fos and cyclin D1. Furthermore, the forced expression of NKX3.1 inhibited IGF-l-induced cell growth. In conclusion, NKX3.1 could downregulate IGF-1R expression and could inhibit IGF-1R-mediated mitogen-activated protein kinase （MAPK）/ERK and AKT signalling pathways, which might partially leads to the inhibition of IGF-l-induced cell growth. This study provides new insights into the molecular mechanisms that NKX3,1 exerts against prostate cancer and ultimately expands the scope of alternative approaches in advanced prostate cancer therapy.

Qualitative Study on Health Self-Help Behavior of the Elderly in a Community

Objective:To investigate the current status quo of health self-help behavior of elderly in a community and its influencing factors using a semi-structured interview in a qualitative study.Methods:A phenomenological method is employed for purposive sampling and snowball sampling methods.The elderly(>60 years old),who had lived in the Minhang District of Shanghai for>5 years,with an annual residence duration≥10 months,were selected.Data were collected in person by a semi-structured and an in-depth interview;the topics were identified according to data arrangement,analysis,and coding.Results:A total of 10 subjects were enrolled,from Pujiang Town,Minhang District of Shanghai.The cohort constituted of 7 males and 3 females,aged 60-68 years,with an average of(63.40±9.19)years.After data arrangement and analysis,the following topics were obtained:(1)various forms of health self-help behaviors existed among elderly in the community;(2)some factors influenced the health self-help behavior among the elderly in the community;(3)a deviation was observed in the health self-help behavior among the elderly in the community.Conclusion:The health self-help behaviors of the elderly in the community should be rectified to carry out self and the environmental establishment of the health self-help behaviors of the elderly in the community,as well as,to guide and develop the personalized health self-help behavior program.