The antitumor potency of the mTOR inhibitor rapamycin (sirolimus) is the subject of intense investigations. Primary effusion lymphoma (PEL) appears as an AIDSdefining lymphoma and like Kaposi sarcoma has been linked to Kaposi sarcomaassociated herpesvirus (KSHV). We find that (1) rapamycin is efficacious against PEL in culture and in a murine xenograft model; (2) mTOR, its activator Akt, and its target p70S6 kinase are phosphorylated in PEL; (3) rapamycin inhibits mTOR signaling as determined by S6 phosphorylation; (4) KSHV transcription is unaffected; (5) inhibition of IL-10 signaling correlates with drug sensitivity; and (6) IntroductionOrgan transplant recipients are at an increased risk of Kaposi sarcoma (KS) and certain viral lymphomas because iatrogenic T-cell immunosuppression activates the causative agent of KS the Kaposi sarcoma-associated herpesvirus (KSHV/HHV-8). 1-6 KSHV was originally identified in the context of HIV-1-induced T-cell depletion 7 and is, by an overwhelming body of evidence, associated with KS as well as the B-cell lymphoproliferative diseases multicentric Castleman disease and primary effusion lymphoma (PEL). [8][9][10] KHSV normally resides latent in a yet to be defined B-lymphocyte compartment. 11 Immunosuppression is thought to disturb host surveillance of this virus, leading to reactivation, increased systemic viral load, [12][13][14][15] and infection of endothelial cells. KSHV-infected LYVE-1 ϩ (lymphatic vessel hyaluronan receptor-1), CD34 ϩ lymphatic endothelial cells constitute the proliferating tumor cells in a KS lesion. [16][17][18][19][20] In 2005, Stallone et al 21 reported that switching from the immunosuppressant drug cyclosporine A to the immunosuppressant drug rapamycin (sirolimus) cured cutaneous KS in a group of 15 kidney transplant recipients. Over a 3-month period all KS lesions disappeared, whereas graft function remained level. This study separated the immunosuppressive function from the anticancer effect of rapamycin in a clinical setting and prompted us to evaluate rapamycin for PEL.The mammalian target of rapamycin (mTOR) executes essential functions of Akt, which is also called protein kinase B, with regard to cancer cell growth and proliferation (reviewed in Hay 22 ). Akt is among the most frequently activated kinases in human cancer. Receptor-tyrosine kinases activate Akt through the generation of phosphoinositol-3,4,5 phosphate (PI3K), which leads to Akt phosphorylation at Thr 308 (through PI3K-dependent kinase 1) and Ser 473 (through PI3K-dependent kinase 2). Generation of PI3K is counteracted by the phosphatase and tensin homolog deleted on chromosome 10 (PTEN) tumor suppressor gene. Phosphorylation at both Thr 308 and Ser 473 is required for full activation of Akt. Akt phosphorylates and thereby inhibits tuberous sclerosis complex 2 (TSC2), which heterodimerizes with TSC1. The TSC1-TSC2 heterodimer has GTPase activity, which inhibits the small G protein Rheb. Rheb is required for mTOR activation. Hence, TSC1 and TSC2 are considered tumor suppressor ...

BackgroundAs the multipotent progenitor population of the airway epithelium, human airway basal cells (BC) replenish the specialized differentiated cell populations of the mucociliated airway epithelium during physiological turnover and repair. Cultured primary BC divide a limited number of times before entering a state of replicative senescence, preventing the establishment of long-term replicating cultures of airway BC that maintain their original phenotype.MethodsTo generate an immortalized human airway BC cell line, primary human airway BC obtained by brushing the airway epithelium of healthy nonsmokers were infected with a retrovirus expressing human telomerase (hTERT). The resulting immortalized cell line was then characterized under non-differentiating and differentiating air-liquid interface (ALI) culture conditions using ELISA, TaqMan quantitative PCR, Western analysis, and immunofluorescent and immunohistochemical staining analysis for cell type specific markers. In addition, the ability of the cell line to respond to environmental stimuli under differentiating ALI culture was assessed.ResultsWe successfully generated an immortalized human airway BC cell line termed BCi-NS1 via expression of hTERT. A single cell derived clone from the parental BCi-NS1 cells, BCi-NS1.1, retains characteristics of the original primary cells for over 40 passages and demonstrates a multipotent differentiation capacity into secretory (MUC5AC, MUC5B), goblet (TFF3), Clara (CC10) and ciliated (DNAI1, FOXJ1) cells on ALI culture. The cells can respond to external stimuli such as IL-13, resulting in alteration of the normal differentiation process.ConclusionDevelopment of immortalized human airway BC that retain multipotent differentiation capacity over long-term culture should be useful in understanding the biology of BC, the response of BC to environmental stress, and as a target for assessment of pharmacologic agents.

Reaching the full potential of precision medicine depends on the quality of personalized genome interpretation. In order to facilitate precision medicine in regions of the Middle East and North Africa (MENA), a population-specific genome for the indigenous Arab population of Qatar (QTRG) was constructed by incorporating allele frequency data from sequencing of 1,161 Qataris, representing 0.4% of the population. A total of 20.9 million single nucleotide polymorphisms (SNPs) and 3.1 million indels were observed in Qatar, including an average of 1.79% novel variants per individual genome. Replacement of the GRCh37 standard reference with QTRG in a best practices genome analysis workflow resulted in an average of 7* deeper coverage depth (an improvement of 23%) and 756,671 fewer variants on average, a reduction of 16% that is attributed to common Qatari alleles being present in QTRG. The benefit for using QTRG varies across ancestries, a factor that should be taken into consideration when selecting an appropriate reference for analysis.

BackgroundLittle is known about health risks associated with electronic cigarette (EC) use although EC are rising in popularity and have been advocated as a means to quit smoking cigarettes.MethodsTen never-smokers, without exposure history to tobacco products or EC, were assessed at baseline with questionnaire, chest X-ray, lung function, plasma levels of endothelial microparticles (EMP), and bronchoscopy to obtain small airway epithelium (SAE) and alveolar macrophages (AM). One week later, subjects inhaled 10 puffs of “Blu” brand EC, waited 30 min, then another 10 puff; n = 7 were randomized to EC with nicotine and n = 3 to EC without nicotine to assess biological responses in healthy, naive individuals.ResultsTwo hr. post-EC exposure, subjects were again assessed as at baseline. No significant changes in clinical parameters were observed. Biological changes were observed compared to baseline, including altered transcriptomes of SAE and AM for all subjects and elevated plasma EMP levels following inhalation of EC with nicotine.ConclusionsThis study provides in vivo human data demonstrating that acute inhalation of EC aerosols dysregulates normal human lung homeostasis in a limited cohort of healthy naïve individuals. These observations have implications to new EC users, nonsmokers exposed to secondhand EC aerosols and cigarette smokers using EC to quit smoking.Trial registrationClinicalTrials.gov NCT01776398 (registered 10/12/12), NCT02188511 (registered 7/2/14).Electronic supplementary materialThe online version of this article (10.1186/s12931-018-0778-z) contains supplementary material, which is available to authorized users.

The small airway epithelium (SAE), the first site of smoking-induced lung pathology, exhibits genome-wide changes in gene expression in response to cigarette smoking. Based on the increasing evidence that the epigenome can respond to external stimuli in a rapid manner, we assessed the SAE of smokers for genome-wide DNA methylation changes compared with nonsmokers, and whether changes in SAE DNA methylation were linked to the transcriptional output of these cells. Using genome-wide methylation analysis of SAE DNA of nonsmokers and smokers, the data identified 204 unique genes differentially methylated in SAE DNA of smokers compared with nonsmokers, with 67% of the regions with differential methylation occurring within 2 kb of the transcriptional start site. Among the genes with differential methylation were those related to metabolism, transcription, signal transduction and transport. For the differentially methylated genes, 35 exhibited a correlation with gene expression, 54% with an inverse correlation of DNA methylation with gene expression and 46% a direct correlation. These observations provide evidence that cigarette smoking alters the DNA methylation patterning of the SAE and that, for some genes, these changes are associated with the smoking-related changes in gene expression.