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The binding of exogenous nicotine to nicotinic acetylcholine (ACh) receptors (nAChR) and the binding of endogenous ACh to both nAChR and muscarinic ACh receptors (mAChR) stimulate growth of both small cell and non–small cell lung carcinomas. Understanding how cholinergic signaling is up-regulated in lung cancer may suggest new therapeutic approaches. Analysis of 28 squamous cell lung carcinomas (SCC) showed increased levels of α5 and β3 nAChR mRNA and increased levels of ACh associated with increased levels of choline acetyltransferase mRNA and decreased cholinesterase mRNAs. Lynx1, an allosteric inhibitor of nAChR activity, was also decreased in SCC. Thus, cholinergic signaling is broadly increased in SCC caused by increased levels of receptors, increased levels of ligands, and decreased levels of receptor inhibitors. Partially explaining the cholinergic up-regulation seen in SCC, incubation of the H520 SCC cell line with nicotine increased levels of ACh secretion, increased expression of nAChR, and, as measured by electrophysiologic recording, increased activity of the expressed nAChR. Consistent with these effects, nicotine stimulated proliferation of H520 cells. One approach to blocking proliferative effects of nicotine and ACh on growth of lung cancers may be through M3 mAChR antagonists, which can limit the activation of mitogen-activated protein kinase that is caused by both nicotinic and muscarinic signaling. This was tested with the M3-selective muscarinic antagonist darifenacin. Darifenacin blocked nicotine-stimulated H520 growth in vitro and also blocked H520 growth in nude mice in vivo. Thus, cholinergic signaling is broadly up-regulated in SCC and blocking cholinergic signaling can limit basal and nicotine-stimulated growth of SCC. [Cancer Res 2008;68(12):4693–700]

Background: Accurate preterm birth data are necessary for population health surveillance and to guide preterm birth initiatives. Gestational age is not routinely or accurately documented in many low-resource nations, however. Metabolic testing of newborn dried blood spots has been used to develop algorithms that yield accurate preterm birth estimates in North America. This study sought to validate published gestational age estimation models in infants born in Bangladesh. Methods: This was a prospective cohort study nested within the Preterm and Stillbirth Study, Matlab. The gestational age of all infants was confirmed by first trimester ultrasound. Cord blood and heel-prick blood spots were collected and analyzed at a provincial newborn screening facility in Ottawa, Canada. The performance of previously-published gestational age algorithms developed from heel-prick data to derive gestational age and preterm birth estimates was evaluated. Findings: 1036 cord blood and 487 heel-prick samples were collected from 1069 unique newborns. When applied to heel-prick metabolic profiles, published algorithms correctly estimated gestational age to within 1.07 weeks and accurately estimated gestational age to within 2 weeks for 94.3% of infants. Model performance was modestly reduced when applied to cord blood samples and accurately estimated gestational age to within 2 weeks for 90.3% of infants. Areas under the curve for distinguishing preterm births from term births were 0.945 (95%CI 0.890-0.999) for heel-prick samples and 0.894 (95%CI 0.853-0.935) for cord blood data. Interpretation: Metabolic gestational age dating provides accurate population-level estimates of gestational age and preterm birth burden. Models are effective on data obtained from both heel prick and cord blood, with the latter as a potentially more feasible option for deriving preterm birth estimates in low resource settings. Funding: This study was supported by the Bill & Melinda Gates Foundation [OPP1141535]. Declaration of Interest: The authors report no conflicts of interest Ethical Approval: Mothers provided informed consent for their infants to be included in the PreSSMat birth cohort and to have clinical data, cord blood and newborn heel prick samples collected and analysed. The present study was approved by the Research Review and Ethical Review Committees of the International Centre for Diarrhoeal Disease Research, Bangladesh (PR-16039). Approvals were also obtained from the Research Ethics Boards of the Ottawa Health Science Network (20160219-01H), and the Children’s Hospital of Eastern Ontario (16/20E).

The binding of exogenous nicotine to nicotinic acetylcholine (ACh) receptors (nAChR) and the binding of endogenous ACh to both nAChR and muscarinic ACh receptors (mAChR) stimulate growth of both small cell and non–small cell lung carcinomas. Understanding how cholinergic signaling is up-regulated in lung cancer may suggest new therapeutic approaches. Analysis of 28 squamous cell lung carcinomas (SCC) showed increased levels of α5 and β3 nAChR mRNA and increased levels of ACh associated with increased levels of choline acetyltransferase mRNA and decreased cholinesterase mRNAs. Lynx1, an allosteric inhibitor of nAChR activity, was also decreased in SCC. Thus, cholinergic signaling is broadly increased in SCC caused by increased levels of receptors, increased levels of ligands, and decreased levels of receptor inhibitors. Partially explaining the cholinergic up-regulation seen in SCC, incubation of the H520 SCC cell line with nicotine increased levels of ACh secretion, increased expression of nAChR, and, as measured by electrophysiologic recording, increased activity of the expressed nAChR. Consistent with these effects, nicotine stimulated proliferation of H520 cells. One approach to blocking proliferative effects of nicotine and ACh on growth of lung cancers may be through M3 mAChR antagonists, which can limit the activation of mitogen-activated protein kinase that is caused by both nicotinic and muscarinic signaling. This was tested with the M3-selective muscarinic antagonist darifenacin. Darifenacin blocked nicotine-stimulated H520 growth in vitro and also blocked H520 growth in nude mice in vivo. Thus, cholinergic signaling is broadly up-regulated in SCC and blocking cholinergic signaling can limit basal and nicotine-stimulated growth of SCC. [Cancer Res 2008;68(12):4693–700]

Preterm birth is a leading cause of infant morbidity and mortality worldwide, but current interventions to prevent prematurity are largely ineffective. Preterm birth is increasingly recognized as an outcome that can result from a variety of pathological processes. Despite current research efforts, the mechanisms underlying these processes remain poorly understood and are influenced by a range of biological and environmental factors. Research with modern techniques is needed to understand the mechanisms responsible for preterm labor and birth and identify targets for diagnostic and therapeutic solutions. This review evaluates the state of reproductive science relevant to understanding the causes of preterm birth, identifies potential targets for prevention, and outlines challenges and opportunities for translating research findings into effective interventions.

Michael Gravett and colleagues review the burden of pregnancy-related infections, especially in low- and middle-income countries, and offer suggestions for a more effective intervention strategy.

The importance of acetylcholine as a neurotransmitter in the nervous system is well established, but little is yet known about its recently described role as an autocrine and paracrine hormone in a wide variety of nonneuronal cells. Consistent with the expression of acetylcholine in normal lung, small cell lung carcinoma (SCLC) synthesize and secrete acetylcholine, which acts as an autocrine growth factor through both nicotinic and muscarinic cholinergic mechanisms. The purpose of this study was to determine if interruption of autocrine muscarinic cholinergic signaling has potential to inhibit SCLC growth. Muscarinic receptor (mAChR) agonists caused concentration-dependent increases in intracellular calcium and mitogen-activated protein kinase (MAPK) and Akt phosphorylation in SCLC cell lines. The inhibitory potency of mAChR subtype–selective antagonists and small interfering RNAs (siRNAs) on acetylcholine-increased intracellular calcium and MAPK and Akt phosphorylation was consistent with mediation by M3 mAChR (M3R). Consistent with autocrine acetylcholine secretion stimulating MAPK and Akt phosphorylation, M3R antagonists and M3R siRNAs alone also caused a decrease in basal levels of MAPK and Akt phosphorylation in SCLC cell lines. Treatment of SCLC cells with M3R antagonists inhibited cell growth both in vitro and in vivo and also decreased MAPK phosphorylation in tumors in nude mice in vivo. Immunohistochemical staining of SCLC and additional cancer types showed frequent coexpression of acetylcholine and M3R. These findings suggest that M3R antagonists may be useful adjuvants for treatment of SCLC and, potentially, other cancers. [Cancer Res 2007;67(8):3936–44]

Background Nonhuman primates (NHPs) are essential for biomedical research due to their similarities to humans. The utility of NHPs will be greatly increased by the application of genomics-based approaches such as gene expression profiling. Sequence information from the 3' end of genes is the key resource needed to create oligonucleotide expression arrays. Results We have developed the algorithms and procedures necessary to quickly acquire sequence information from the 3' end of nonhuman primate orthologs of human genes. To accomplish this, we identified terminal exons of over 15,000 human genes by aligning mRNA sequences with genomic sequence. We found the mean length of complete last exons to be approximately 1,400 bp, significantly longer than previous estimates. We designed primers to amplify genomic DNA, which included at least 300 bp of the terminal exon. We cloned and sequenced the PCR products representing over 5,500 Macaca mulatta (rhesus monkey) orthologs of human genes. This sequence information has been used to select probes for rhesus gene expression profiling. We have also tested 10 sets of primers with genomic DNA from Macaca fascicularis (Cynomolgus monkey), Papio hamadryas (Baboon), and Chlorocebus aethiops (African green monkey, vervet). The results indicate that the primers developed for this study will be useful for acquiring sequence from the 3' end of genes for other nonhuman primate species. Conclusion This study demonstrates that human genomic DNA sequence can be leveraged to obtain sequence from the 3' end of NHP orthologs and that this sequence can then be used to generate NHP oligonucleotide microarrays. Affymetrix and Agilent used sequences obtained with this approach in the design of their rhesus macaque oligonucleotide microarrays.