The effectiveness of a transtheoretical model-based smoking cessation intervention for rural smokers: A quasi-experimental longitudinal study.

OBJECTIVE: Cigarette smoking is highly prevalent, despite being a primary preventable cause of disease and mortality. This study examined the effect of a Transtheoretical Model (TTM)-based psychoeducational intervention for smoking cessation (SC) on knowledge, SC-related parameters, and progression through the TTM stages of change among rural smokers. METHODS: This quasi-experimental study recruited 200 smokers from an outpatient clinic. The comparison group was recruited before the experimental group to address possible self-selection bias. Structured questionnaires were administered pre- and post-intervention (three months) and at follow-up (six months). RESULTS: A generalised estimation equation model indicated that the TTM-based intervention significantly increased participants' SC-knowledge and improved progression through TTM stages by the six-month follow-up. No significant group differences were found in self-efficacy and nicotine dependence scores or daily cigarette consumption. CONCLUSIONS: A TTM-based intervention enhances SC-knowledge and fosters progress through change stages. However, it does not directly impact nicotine dependence or cigarette consumption. Outpatient settings may employ TTM-based programmes for SC education and motivation. Detecting anticipated effects may require a longer intervention duration exceeding six months. PRACTICE IMPLICATIONS: Such TTM-based programmes may facilitate SC-knowledge and motivation in outpatient settings. Further research to comprehend patients' context and experiences during the stages of change is required.

A novel oncogenic role of inositol phosphatase SHIP2 in ER-negative breast cancer stem cells: involvement of JNK/vimentin activation.

Overexpression of SH2-containing-5'-inositol phosphatase-2 (SHIP2) correlates with poor survival in breast cancer. However, its role in breast cancer stem cells (BCSCs) remains unclear. Here, we showed that the percentage of SHIP2(+) cells was positively correlated with that of CD24(-) CD44(+) cells in 60 breast cancer specimens. Among 20 estrogen receptor (ER)-negative samples, 17 had greater SHIP2 expression in CD24(-) CD44(+) subpopulation than the remaining subpopulation. Data mining of microarray analysis of 295 breast tumors showed a significant correlation of higher SHIP2 expression with distant metastasis. Examination of patient-derived mouse xenografts revealed that SHIP2 protein and its tyrosine 1135 phosphorylation were significantly higher in BCSCs, identified as CD24(-) CD44(+) or aldehyde dehydrogenase (ALDH(+)), than non-BCSCs. SHIP2 silencing or inhibitor of SHIP2 phosphatase significantly decreased mammosphere-forming efficiency, ALDH(+) subpopulation in vitro and tumorigenicity of BCSCs in vivo. Overexpression of SHIP2 enhanced the expression of epithelial-mesenchymal transition markers including vimentin (VIM), which was mainly expressed in ER-negative breast cancer cells with higher level in mammospheres than monolayer culture. Ablation of c-Jun N-terminal kinase 1 (JNK1), JNK2, or VIM diminished the increased ALDH(+) population and tumorigenicity, induced by SHIP2 overexpression. BCSCs displayed greater expression of phospho-JNK than non-BCSCs and silencing of JNK suppressed SHIP2-mediated upregulation of VIM. Furthermore, SHIP2 overexpression enhanced Akt activation, but Akt inhibition failed to influence SHIP2-induced phospho-JNK/VIM upregulation. In conclusion, SHIP2 plays a key role in BCSCs of ER-negative breast cancers through activation of Akt and JNK with upregulation of VIM and may serve as a target for therapy directed at BCSCs.

The expression and significance of insulin-like growth factor-1 receptor and its pathway on breast cancer stem/progenitors.

INTRODUCTION: Dysregulation of the insulin-like growth factor-1 receptor (IGF-1R)/phosphatidylinositol-3-kinase (PI3K)/Akt pathway was shown to correlate with breast cancer disease progression. Cancer stem cells are a subpopulation within cancer cells that participate in tumor initiation, radio/chemoresistance and metastasis. In breast cancer, breast cancer stem cells (BCSCs) were identified as CD24-CD44+ cells or cells with high intracellular aldehyde dehydrogenase activity (ALDH+). Elucidation of the role of IGF-1R in BCSCs is crucial to the design of breast cancer therapies targeting BCSCs. METHODS: IGF-1R expression in BCSCs and noncancer stem cells sorted from xenografts of human primary breast cancers was examined by fluorescence-activated cell sorting (FACS), western blot analysis and immunoprecipitation. The role of IGF-1R in BCSCs was assessed by IGF-1R blockade with chemical inhibitor and gene silencing. Involvement of PI3K/Akt/mammalian target of rapamycin (mTOR) as the downstream pathway was studied by their phosphorylation status upon IGF-1R inhibition and the effects of chemical inhibitors of these signaling molecules on BCSCs. We also studied 16 clinical specimens of breast cancer for the expression of phosphor-Akt in the BCSCs by FACS. RESULTS: Expression of phosphorylated IGF-1R was greater in BCSCs than in non-BCSCs from xenografts of human breast cancer, which were supported by western blot and immunoprecipitation experiments. The sorted IGF-1R-expressing cells displayed features of cancer stem/progenitors such as mammosphere formation in vitro and tumorigenicity in vivo, both of which were suppressed by knockdown of IGF-1R. A specific inhibitor of the IGF-1R, picropodophyllin suppressed phospho-AktSer473 and preferentially decreased ALDH+ BCSC populations of human breast cancer cells. Furthermore, picropodophyllin inhibited the capacity of CD24-CD44+ BCSCs to undergo the epithelial-mesenchymal transition process with downregulation of mesenchymal markers. Inhibitors of signal molecules downstream of IGF-1R including PI3K/Akt/mTOR also reduced the ALDH+ population of breast cancer cells. Furthermore, the mTOR inhibitor, rapamycin, suppressed BCSCs in vitro and in vivo. CONCLUSION: Our data support the notion that IGF-1R is a marker of stemness, and IGF-1R and its downstream PI3K/Akt/mTOR pathway are attractive targets for therapy directed against breast cancer stem/progenitors.