Previously, we have shown somatostatin receptor (SSTR) subtype-specific regulation of growth hormone (GH), thyroid-stimulating hormone, and prolactin (PRL) secretion in human fetal pituitary cultures, where GH and thyroid-stimulating hormone are mediated by both SSTR2 and SSTR5, whereas SSTR2 preferentially mediates PRL secretion. We now tested SSTR subtype-selective analogues in primary human GH-and PRL-secreting pituitary adenoma cultures. Analogue affinities determined by membrane radioligand binding in cells stably expressing human SSTR forms were either SSTR2 or SSTR5-selective. Analogues preferential either for SSTR2, including octreotide, lanreotide, and novel compounds with improved affinity for SSTR2, or new SSTR5-selective compounds suppressed GH in tumor cell cultures (up to 44% of control; P Ͻ 0.0005). However, novel analogues from both groups were 30-40% more potent than octreotide and lanreotide in suppressing GH ( P Ͻ 0.05). Heterologous analogue combinations containing both SSTR2-and SSTR5-selective compounds were more potent in decreasing GH than analogues used alone ( P Ͻ 0.05), or than combinations of compounds specific for the same receptor subtype ( P Ͻ 0.005). In contrast, SSTR2-selective analogues did not suppress PRL release from six cultured prolactinomas studied. However, new SSTR5-selective analogues suppressed in vitro PRL secretion (30-40%; P Ͻ 0.05) in four of six prolactinomas. These results suggest that both SSTR2 and SSTR5 are involved in GH regulation in somatotroph adenoma cells, whereas SSTR5 exclusively regulates PRL secretion from prolactinoma cells. Thus, somatostatin analogues with improved selective binding affinity for these receptor subtypes may be effective in the treatment of either GH-or PRL-secreting adenomas. ( J. Clin. Invest. 1997. 100: 2386-2392.)

BackgroundA sensitive assay to identify biomarkers using non-invasively collected clinical specimens is ideal for breast cancer detection. While there are other studies showing disease biomarkers in saliva for breast cancer, our study tests the hypothesis that there are breast cancer discriminatory biomarkers in saliva using de novo discovery and validation approaches. This is the first study of this kind and no other study has engaged a de novo biomarker discovery approach in saliva for breast cancer detection. In this study, a case-control discovery and independent preclinical validations were conducted to evaluate the performance and translational utilities of salivary transcriptomic and proteomic biomarkers for breast cancer detection.Methodology/Principal FindingsSalivary transcriptomes and proteomes of 10 breast cancer patients and 10 matched controls were profiled using Affymetrix HG-U133-Plus-2.0 Array and two-dimensional difference gel electrophoresis (2D-DIGE), respectively. Preclinical validations were performed to evaluate the discovered biomarkers in an independent sample cohort of 30 breast cancer patients and 63 controls using RT-qPCR (transcriptomic biomarkers) and quantitative protein immunoblot (proteomic biomarkers). Transcriptomic and proteomic profiling revealed significant variations in salivary molecular biomarkers between breast cancer patients and matched controls. Eight mRNA biomarkers and one protein biomarker, which were not affected by the confounding factors, were pre-validated, yielding an accuracy of 92% (83% sensitive, 97% specific) on the preclinical validation sample set.ConclusionsOur findings support that transcriptomic and proteomic signatures in saliva can serve as biomarkers for the non-invasive detection of breast cancer. The salivary biomarkers possess discriminatory power for the detection of breast cancer, with high specificity and sensitivity, which paves the way for prediction model validation study followed by pivotal clinical validation.

Lung cancer is the leading cause of cancer death for both men and women worldwide. Since most of the symptoms found for lung cancer are nonspecific, diagnosis is mostly done at late and progressed stage with the consecutive poor therapy outcome. Effective early detection techniques are sorely needed. The emerging field of salivary diagnostics could provide scientifically credible, easy-to-use, non-invasive and cost-effective detection methods. Recent advances have allowed us to develop discriminatory salivary biomarkers for a variety of diseases from oral to systematic diseases. In this study, salivary transcriptomes of lung cancer patients were profiled and led to the discovery and pre-validation of seven highly discriminatory transcriptomic salivary biomarkers (BRAF, CCNI, EGRF, FGF19, FRS2, GREB1, and LZTS1). The logistic regression model combining five of the mRNA biomarkers (CCNI, EGFR, FGF19, FRS2, and GREB1) could differentiate lung cancer patients from normal control subjects, yielding AUC value of 0.925 with 93.75 % sensitivity and 82.81 % specificity in the pre-validation sample set. These salivary mRNA biomarkers possess the discriminatory power for the detection of lung cancer. This report provides the proof of concept of salivary biomarkers for the non-invasive detection of the systematic disease. These results poised the salivary biomarkers for the initiation of a multi-center validation in a definitive clinical context.

Insulin-like growth factor-binding protein-3 (IGFBP-3) induces apoptosis by its ability to bind insulin-like growth factors (IGFs) as well as its IGF-independent effects involving binding to other molecules including the retinoid X receptor-␣ (RXR␣).Here we describe that in response to IGFBP-3, the RXR␣ binding partner nuclear receptor Nur77 rapidly undergoes translocation from the nucleus to the mitochondria, initiating an apoptotic cascade resulting in caspase activation within 6 h. This translocation is a type 1 IGF receptor-signaling independent event as IGFBP-3 induces Nur77 translocation in R-cells. IGFBP-3 and Nur77 are additive in inducing apoptosis. GFP-Nur77 transfection into RXR␣ wildtype and knock-out mouse embryonic fibroblasts and subsequent treatment with IGFBP-3 show that RXR␣ is required for IGFBP-3-induced Nur77 translocation and apoptosis. Addition of IGFBP-3 to 22RV1 cell lysates enhanced the ability of GST-RXR␣ to "pull down" Nur77, and overexpression of IGFBP-3 enhanced the accumulation of mitochondrial RXR␣. This unique nongenotropic nuclear pathway supports an emerging role for IGFBP-3 as a novel, multicompartmental signaling molecule involved in induction of apoptosis in malignant cells.Over the past decade, multiple lines of investigation have validated insulin-like growth factor-binding protein-3 (IGFBP-3)1 as an inducer of cellular apoptosis, effects that can be unrelated to its IGF binding (1). Most importantly, several groups have now reported successful in vivo treatment of cancer models with IGFBP-3, either as a single agent or in combination with chemotherapeutic agents (2-4). However, the molecular mechanisms by which IGFBP-3 induces apoptosis remain largely unknown at present.Several novel IGFBP-3 binding partners have been recently identified that may participate in its IGF-independent proapoptotic effects (1). We and others demonstrated that retinoid X receptor-␣ (RXR␣) is a binding partner for IGFBP-3 (5, 6) and that RXR␣ is required for IGFBP-3 apoptotic effects (5). Indeed, IGFBP-3 potentiates RXRE-mediated signaling while inhibiting signaling via other RXR␣ heterodimeric partners (5-7). Our discovery of IGFBP-3 binding to RXR␣ suggested that its apoptotic effects might involve an RXR␣-dependent transcriptional mechanism. Most published reports have evaluated IGFBP-3-induced apoptosis at 24 -72 h (8 -11), consistent with a transcriptional mechanism. However, we have recently described apoptosis activation by IGFBP-3 (as evidenced by caspase activation and histone associated DNA fragmentation ELISA) as early as 1-6 h after IGFBP-3 exposure, suggesting a mechanism that does not require de novo gene transcription (12, 13). The orphan nuclear receptor Nur77 (also known as NGFI-B (14) and TR3 (15)) is a nuclear receptor transcription factor and is an important regulator of apoptosis in different cells (16). It is a member of the orphan steroid receptor family, which also includes Nor1 and Nurr1. This family is essential for apoptosis of self-reactive immature thymocytes followi...

We have discovered and validated a panel of salivary exRNA biomarkers with credible clinical performance for the detection of GC. Our study demonstrates the potential utility of salivary exRNA biomarkers in screening and risk assessment for GC.

We have shown recently that leukemia inhibitory factor (LIF) and oncostatin M (OSM), two members of the gp130-dependent cytokine family, stimulate murine proopiomelanocortin (

BACKGROUND: Current standard operating procedures for salivary transcriptomic analysis require low temperatures and lengthy mRNA isolation, which substantially hamper its use in the clinic. We developed a streamlined, ambient-temperature processing, stabilization, and storage protocol for clinical analysis of salivary RNA.

Background/Aims: Microbes reside in a number of body sites, including the oral cavity, and are associated with the progression of many systemic diseases. In this study, we aimed to investigate the effects of gout and hyperuricemia (HUA) on the composition of oral microbiomes. Methods: Analysis of the oral microbiota from 12 gout patients, 11 HUA patients, and 19 healthy control subjects was performed using a deep sequencing approach, and validation of significant changes in Prevotella intermedia and Serratia marcescens in new patient cohorts was performed using quantitative PCR (qPCR). Results: Our analysis indicated that both gout and HUA significantly altered the composition of the oral microbiome in patients. Patients with gout or HUA had significantly greater levels of salivary Prevotella intermedia but significantly lower levels of Serratia marcescens than healthy control subjects. Conclusion: We demonstrated the association between the oral microbiome and gout and HUA for the first time. In particular, 16S sequencing and qPCR analysis revealed significantly higher levels of oral Prevotella intermedia in gout/HUA patients, which suggests that these patients might be at risk for the development of periodontitis.