Nicotine increases the resistance of lung cancer cells to cisplatin through enhancing Bcl-2 stability.

Br J Cancer. 2014 Feb 18;

Authors: Nishioka T, Luo LY, Shen L, He H, Mariyannis A, Dai W, Chen C

Abstract
Background:Nicotine is able to activate mitogenic signalling pathways, which promote cell growth or survival as well as increase chemoresistance of cancer cells. However, the underlying mechanisms are not fully understood.Methods:In this study, we used immunoblotting and immunoprecipitation methods to test the ubiquitination and degradation of Bcl-2 affected by nicotine in lung cancer cells. Apoptotic assay was also used to measure the antagonising effect of nicotine on cisplatin-mediated cytotoxicity.Results:We demonstrated that the addition of nicotine greatly attenuated Bcl-2 ubiquitination and degradation, which further desensitised lung cancer cells to cisplatin-induced cytotoxicity. In this process, Bcl-2 was persistently phosphorylated in the cells cotreated with nicotine and cisplatin. Furthermore, Akt was proven to be responsible for sustained activation of Bcl-2 by nicotine, which further antagonised cisplatin-mediated apoptotic signalling.Conclusions:Our study suggested that nicotine activates its downstream signalling to interfere with the ubiquitination process and prevent Bcl-2 from being degraded in lung cancer cells, resulting in the increase of chemoresistance.British Journal of Cancer advance online publication, 18 February 2014; doi:10.1038/bjc.2014.78 www.bjcancer.com.

PMID: 24548862 [PubMed - as supplied by publisher]

Lung Cancer Stem Cells and Implications for Future Therapeutics.

Cell Biochem Biophys. 2014 Feb 20;

Authors: Wang J, Li ZH, White J, Zhang LB

Abstract
Lung cancer is the most dreaded of all cancers because of the higher mortality rates associated with it worldwide. The various subtypes of lung cancer respond differently to a particular treatment regime, which makes the therapeutic interventions all the more complicated. The concept of cancer stem cells (CSCs) is based primarily on the clinical and experimental observations that indicate the existence of a subpopulation of cells with the capacity to self-renew and differentiate as well as show increased resistance to radiation and chemotherapy. They are considered as the factors responsible for the cases of tumor relapse. The CSCs may have significant role in the development of lung tumorigenesis based on the identification of the CSCs which respond during injury. The properties of multi-potency and self-renewal are shared in common by the lung CSCs with the normal pluripotent stem cells which can be isolated using the similar markers. This review deals with the origin and characteristics of the lung cancer stem cells. The role of different markers used to isolate lung CSCs like CD44, ALDH (aldehyde dehydrogenase), CD133 and ABCG2 (ATP binding cassette sub family G member 2) have been discussed in detail. Analysis of the developmental signaling pathways such as Wnt/β-catenin, Notch, hedgehog in the regulation and maintenance of the lung CSCs have been done. Finally, before targeting the lung CSC biomarkers for potential therapeutics, challenges faced in lung cancer stem cell research need to be taken into account. With the accepted notion that the CSCs are to blame for cancer relapse and drug resistance, targeting them can be an important aspect of lung cancer therapy in the future.

PMID: 24549856 [PubMed - as supplied by publisher]

Prognostic Impact of Minimal Pleural Effusion in Non-Small-Cell Lung Cancer.

J Clin Oncol. 2014 Feb 18;

Authors: Ryu JS, Ryu HJ, Lee SN, Memon A, Lee SK, Nam HS, Kim HJ, Lee KH, Cho JH, Hwang SS

Abstract
PURPOSE: Minimal (< 10 mm thick) pleural effusion (PE) may represent an early phase of malignant PE, but its clinical relevance has rarely been studied. Therefore, we examined the proportion of minimal PE in patients with non-small-cell lung cancer (NSCLC) and its impact on survival. We also considered possible accumulation mechanisms in our data set.
PATIENTS AND METHODS: On the basis of PE status from chest computed tomography scans at diagnosis, 2,061 patients were classified into three groups: no PE, minimal PE, and malignant PE. Twenty-one variables associated with four factors-patient, stage migration, tumor, and treatment-were investigated for correlation with survival.
RESULTS: Minimal PE presented in 272 patients (13.2%). Of 2,061 patients, the proportion of each stage was the following: 5.2% stage I, 10.9% stage II, 13.2% stage IIIA, 23.8% stage IIIB, and 13.9% stage IV. Minimal PE correlated significantly with shorter survival time than did no PE (median survival time, 7.7 v 17.7 months; log-rank P < .001), even after full adjustment with all variables (adjusted hazard ratio, 1.40; 95% CI, 1.21 to 1.62). Prognostic impact of minimal PE was higher in early versus advanced stages (Pinteraction = .001). In 237 patients (87.8%) with minimal PE, pleural invasion or attachment as a direct mechanism was observed, and it was an independent factor predicting worse survival (P = .03).
CONCLUSION: Minimal PE is a commonly encountered clinical concern in staging NSCLCs. Its presence is an important prognostic factor of worse survival, especially in early-stage disease.

PMID: 24550423 [PubMed - as supplied by publisher]

Dry-powder inhalers in acute asthma.

Ther Deliv. 2014 Jan;5(1):69-81

Authors: Selroos O

Abstract
An updated literature search was performed to evaluate the efficacy of rapid-acting β2-agonists delivered via dry powder inhalers in the treatment of moderate-to-severe acute asthma. Databases were searched from 1985 up to December 2012. A total of 23 randomized, double-blind or open clinical studies in acute asthma comparing the efficacy of a dry powder inhaler with a pressurized metered-dose inhaler or a nebulizer, and performed under controlled hospital conditions, were identified. This review found that administration of β2-agonist bronchodilators via dry powder inhalers (formoterol, salbutamol, terbutaline and budesonide/formoterol) was effective during severe asthma worsening and acute asthma attacks, and was as effective as established therapies with a pressurized metered-dose inhaler with or without a spacer, or nebulization. These results ensure that patients can rely upon dry powder inhalers equally well as other inhaler devices during episodes of asthma worsening.

PMID: 24341818 [PubMed - indexed for MEDLINE]