Search

The biomarker development field within molecular medicine remains limited by the methods that are available for building predictive models. We developed an efficient method for conservatively estimating confidence intervals for the cross validation-derived prediction errors of biomarker models. This new method was investigated for its ability to improve the capacity of our previously developed method, StaVarSel, for selecting stable biomarkers. Compared with the standard cross validation method, StaVarSel markedly improved the estimated generalisable predictive capacity of serum miRNA biomarkers for the detection of disease states that are at increased risk of progressing to oesophageal adenocarcinoma. The incorporation of our new method for conservatively estimating confidence intervals into StaVarSel resulted in the selection of less complex models with increased stability and improved or similar predictive capacities. The methods developed in this study have the potential to improve progress from biomarker discovery to biomarker driven translational research.

Supplementary figure 5. LncRNAs and mutational signatures. IGV coverage plot of two previously characterised lncRNAs (a) AFAP1-AS1, (b) HNF1A-AS1 upregulated in EAC. Coverage is normalised as counts per million reads. (c) TCGA RNA-seq EAC data was utilised to validate neighbor lncRNA-mRNA pair correlation. Through TCGA alignment of Refseq only 15 of our differentially expressed lncRNAs-gene pairs were available in the TCGA data and then subsequently correlated using the same methods as presented in the main article. (d) SNPs in normal samples were removed from this analysis. All NDBE, LGD and EAC patients were investigated for mutational signatures as described. Only mutations covered by {greater than or equal to}20 reads were used to determine the presence of transcriptional mutation signatures (a) Five signatures were identified, which was used to (e) cluster the patients based on each signatures contribution to the patients mutations.

Esophageal adenocarcinoma (EAC) has one of the fastest increases in incidence of any cancer, along with poor five-year survival rates. Barrett's esophagus (BE) is the main risk factor for EAC; however, the mechanisms driving EAC development remain poorly understood. Here, transcriptomic profiling was performed using RNA-sequencing (RNA-seq) on premalignant and malignant Barrett's tissues to better understand this disease. Machine-learning and network analysis methods were applied to discover novel driver genes for EAC development. Identified gene expression signatures for the distinction of EAC from BE were validated in separate datasets. An extensive analysis of the noncoding RNA (ncRNA) landscape was performed to determine the involvement of novel transcriptomic elements in Barrett's disease and EAC. Finally, transcriptomic mutational investigation of genes that are recurrently mutated in EAC was performed. Through these approaches, novel driver genes were discovered for EAC, which involved key cell cycle and DNA repair genes, such as BRCA1 and PRKDC. A novel 4-gene signature (CTSL, COL17A1, KLF4, and E2F3) was identified, externally validated, and shown to provide excellent distinction of EAC from BE. Furthermore, expression changes were observed in 685 long noncoding RNAs (lncRNA) and a systematic dysregulation of repeat elements across different stages of Barrett's disease, with wide-ranging downregulation of Alu elements in EAC. Mutational investigation revealed distinct pathways activated between EAC tissues with or without TP53 mutations compared with Barrett's disease. In summary, transcriptome sequencing revealed altered expression of numerous novel elements, processes, and networks in EAC and premalignant BE.Implications: This study identified opportunities to improve early detection and treatment of patients with BE and esophageal adenocarcinoma. Mol Cancer Res; 15(11); 1558–69. ©2017 AACR.

Supplementary table 1 describes patient demographics and sample sequencing information Supplementary table 2 describes the top 20 differentially expressed genes, and the 12-gene signature. Supplementary table 3 shows the Discriminative performance of EAC driver genes in predicting the presence of EAC compared to BE with or without dysplasia. Supplementary table 4-5 describes the top 20 differentially expressed lncRNAs and repeat elements, respectively. Supplementary table 6 shows the association of genes in 12-signature with malignancies. Searched Pubmed: "Gene & Cancer" Supplementary table 7 shows the primers for lncRNA expression validation.

Antiretroviral therapy (ART) can attain prolonged undetectable HIV-1 in plasma and cerebrospinal fluid (CSF), but brain injury remains prevalent in people living with HIV-1 infection (PLHIV). We investigated cell-associated (CA)-HIV-1 RNA transcripts in cells in CSF and blood, using the highly sensitive Double-R assay, together with proton Magnetic Resonance Spectroscopy ( 1 H MRS) of major brain metabolites, in sixteen PLHIV. 14/16 CSF cell samples had quantifiable CA-HIV-1 RNA, at levels significantly higher than in their PBMCs (median 9,266 vs 185 copies /106 CD4+ T-cells; p+ CD49d + integrin β7-, CCR5 + CD4 + T-cells were highly enriched in CSF, compared with PBMC (p + T cells from blood, rather than trafficking monocytes. Future research should focus on inhibitors of this transcription to reduce local production of potentially neurotoxic and inflammatory viral products.

Objective Some HIV+ patients, virally suppressed on ART, show occasional "blips" of detectable HIV-1 plasma RNA. We used a new highly sensitive assay of cell-associated HIV-1 RNA to measure transcriptional activity in PBMCs and production of infectious virus from the viral reservoir, in patients with and without "blips". Design/methods RNA and DNA extracted from cells in 6 mls of peripheral blood, from suppressed patients with one to two "blip" episodes over the past 2 years of ART (n = 55), or no "blips" (n = 52), were assayed for HIV-1 RNA transcripts and proviral DNA targeting the highly conserved "R" region of the LTR. Follow-up samples were also collected. Purified CD4+ T cells were cultured with anti-CD3/CD28/CD2 T cell activator to amplify transcription and measure replication competent virus. Results HIV-1 RNA transcripts ranged from 1.3 to 5,415 copies/106 white blood cells. "Blip" patients had significantly higher levels vs without blips (median 192 vs 49; p = 0.0007), which correlated with: higher levels of inducible transcripts after activation in vitro, sustained higher HIV-1 transcription levels in follow-up samples along with increasing HIV-1 DNA in some, and production of replication competent HIV-1. Conclusion Viral "blips" are significant reflecting higher transcriptional activity from the reservoir and contribute to the reservoir over time. This sensitive assay can be used in monitoring the size and activity of the HIV-1 reservoir and will be useful in HIV-1 cure strategies.

Prognostic biomarkers for esophageal adenocarcinoma (EAC) remain elusive but may be helpful in treatment planning, as TNM staging often fails to accurately predict survival. Advanced stage patients are treated by peri-operative chemo/radiotherapy; biomarkers associated with survival are thus likely to represent both true prognostic markers as well as markers of response to chemo/radiotherapy. Here we present first-pass genomic findings for a cohort of optimally staged EAC patients treated by surgery alone. DNA was extracted from fresh frozen EAC and matching normal squamous esophageal tissues obtained at esophagectomy from 65 consenting patients who did not receive any neo- or adjuvant chemo- or radiotherapy due to institutional preference at the time of tissue collection. Library preparation and sequencing for a targeted 600 cancer-associated gene panel designed using the Roche/NimbleGen EZ Choice Library NimbleDesign platform were conducted on Illumina-based platforms followed by analysis with an accredited bioinformatics pipeline. The panel design incorporated the entire coding region plus 10 bp of flanking intron of each gene. Mean age 70 yrs; 88% male. All patients underwent an en bloc esophagectomy (mean 35 lymph nodes). TNM (7th ed.) stages were 61% Stage 3, 18% stage 2, 14% stage 1, 6% stage 4. At median 9.5 years follow-up, 20 (31%) patients remained alive. Copy number changes were common, reflecting chromosomal instability. Less than 8% of patients had high tumour mutational burden (>10mut/MB), associated with mutations in DNA repair genes. Commonest somatic mutations included TP53 (HR: 0.43) and LRP1B (HR: 1.7). Pathways implicated included RTK signalling (PIK3CA, EGFR, KRAS), DNA damage (BRCA1, PALB2, MGMT) and histone remodelling (ARID1A, ARID2, KMT2D). Peri-operative treatment means linking genomic changes independent of stage to clinical outcomes is difficult. Neoadjuvant and/or adjuvant treatment is now standard for T2–4 or node positive EAC. This cohort of 65 patients, most of whom had stage 3 disease and all of whom underwent optimal staging with en bloc esophagectomy, represents a unique opportunity to analyze characteristics of EAC without confounding by peri-operative treatment. An EAC-specific DNA sequencing panel approach offers potential for personalized therapy.

ObjectiveDespite effective antiretroviral therapy (ART), brain injury remains prevalent in people living with HIV-1 infection (PLHIV) possibly due to ART’s lack of direct inhibition of transcription with continued local production of viral transcripts and neurotoxic proteins, such as Tat, rather than cell-free whole virion toxicity. We quantified cell-associated (CA) HIV-1 RNA-transcripts in CSF and blood, in relation to proton Magnetic Resonance Spectroscopy (1H MRS) of major brain metabolites, in well characterised PLHIV.MethodsRNA was extracted from cells in 16 paired samples of CSF and blood, from PLHIV on fully suppressive ART. HIV-1 CA-RNA copies were measured using the highly sensitive Double-R assay and normalized /106 CD4+ T cells. 18-colour flow cytometry was used to count and analyse CD4+ T cells and monocytes in CSF and blood. The concentrations of major brain metabolites from 1H MRS in frontal white matter (FWM), posterior cingulate cortex (PCC), and caudate areas were measured. Brain injury in each voxel was defined using a composite score derived by principal component analysis.Results14/16 CSF cell samples had quantifiable HIV-1 CA-RNA transcripts, at levels significantly higher than in their PBMCs (median 9,266 vs 185 copies /106 CD4+ T cells; p90% CD14+CD16+ phenotype). CXCR3+CD49d+integrin ß7-negative, CCR5+ CD4+ T cells were significantly enriched in CSF, compared with PBMC (p ConclusionsElevated HIV-1 transcripts in CSF cells were associated with in vivo brain injury, despite suppressive ART. The cellular source is most likely the predominant CXCR3+ CD49d+ integrinß7-CCR5+ memory CD4+ T cells, not monocytes. Inhibitors of transcription to reduce local production of potentially neurotoxic proteins, should be developed.

Esophageal adenocarcinoma (EAC) has one of the fastest increases in incidence of any cancer, along with poor five-year survival rates. Barrett's esophagus (BE) is the main risk factor for EAC; however, the mechanisms driving EAC development remain poorly understood. Here, transcriptomic profiling was performed using RNA-sequencing (RNA-seq) on premalignant and malignant Barrett's tissues to better understand this disease. Machine-learning and network analysis methods were applied to discover novel driver genes for EAC development. Identified gene expression signatures for the distinction of EAC from BE were validated in separate datasets. An extensive analysis of the noncoding RNA (ncRNA) landscape was performed to determine the involvement of novel transcriptomic elements in Barrett's disease and EAC. Finally, transcriptomic mutational investigation of genes that are recurrently mutated in EAC was performed. Through these approaches, novel driver genes were discovered for EAC, which involved key cell cycle and DNA repair genes, such as BRCA1 and PRKDC. A novel 4-gene signature (CTSL, COL17A1, KLF4, and E2F3) was identified, externally validated, and shown to provide excellent distinction of EAC from BE. Furthermore, expression changes were observed in 685 long noncoding RNAs (lncRNA) and a systematic dysregulation of repeat elements across different stages of Barrett's disease, with wide-ranging downregulation of Alu elements in EAC. Mutational investigation revealed distinct pathways activated between EAC tissues with or without TP53 mutations compared with Barrett's disease. In summary, transcriptome sequencing revealed altered expression of numerous novel elements, processes, and networks in EAC and premalignant BE. Implications: This study identified opportunities to improve early detection and treatment of patients with BE and esophageal adenocarcinoma. Mol Cancer Res; 15(11); 1558–69. ©2017 AACR.

BACKGROUND: Esophageal and gastroesophageal junctional (GEJ) adenocarcinoma is one of the most fatal cancers and has the fastest rising incidence rate of all cancers. Identification of biomarkers is needed to tailor treatments to each patient's tumor biology and prognosis. METHODS: Gene expression profiling was performed in a test cohort of 80 chemoradiotherapy (CRTx) naïve patients with external validation in a separate cohort of 62 CRTx naïve patients and 169 patients with advanced stage disease treated with CRTx. RESULTS: As a novel prognostic biomarker after external validation CD151 showed promise. Patients exhibiting high levels of CD151 (=median) had a longer median overall survival than patients with low CD151 tumor levels (median not reached vs. 30.9 months; p = 0.01). This effect persisted in a multivariable Cox regression model with adjustment for tumor stage [adjusted hazard ratio (aHR) 0.33; 95 confidence interval (CI) 0.14 0.78; p = 0.01] and was further corroborated through immunohistochemical analysis (aHR 0.22; 95 CI 0.08 0.59; p = 0.003). This effect was not found in the separate cohort of CRTx exposed patients. CONCLUSION: Tumoral expression levels of CD151 may provide independent prognostic information not gained by conventional staging of patients with esophageal and GEJ adenocarcinoma treated by esophagectomy alone.

Background Epidemiological studies have identified obesity as a major risk factor for cancer in humans, and trials have demonstrated a significant reduction in the incidence of cancer after bariatric surgery. The rapidity of weight loss after bariatric surgery provides an opportunity to identify the molecular changes associated with effective obesity treatment. Indirectly, this may provide some insights into the mechanisms that drive the association between obesity and cancer. We sought to measure circulating cancer-associated proteins before and after laparoscopic sleeve gastrectomy (LSG). Methods We prospectively enrolled 15 patients undergoing LSG. Thirty-four plasma protein biomarkers thought to be associated with cancer processes were analyzed at baseline and following successful weight loss at 12 weeks using a multiplex bead-based assay. Results Mean excess body weight loss was 44 % at 12-week follow-up. After LSG, a significant reduction in circulating plasma levels was observed for half (17/34) of the proteins assessed: VEGF-A, VEGF-C, VEGF-D, endoglin, PLGF, sFASL, IGFBP-1, IL-18, prolactin, EGF, TGFα, sCD40L, IL-18, TNFα, IL-6, HB-EGF, and PAI-1. Nonsignificant decreases were found for the remaining proteins. Conclusions Circulating cancer-related biomarker levels were reduced by surgical weight loss, and this benefit was achieved as early as 3 months after operation. The observed reduction in cancer biomarkers may be related to the reported decrease in cancer incidence following bariatric surgery.

Barrett's esophagus (BE), a common condition, is the only known precursor to esophageal adenocarcinoma (EAC). There is uncertainty about the best way to manage BE as most people with BE never develop EAC and most patients diagnosed with EAC have no preceding diagnosis of BE. Moreover, there have been recent advances in knowledge and practice about the management of BE and early EAC. To aid clinical decision making in this rapidly moving field, Cancer Council Australia convened an expert working party to identify pertinent clinical questions. The questions covered a wide range of topics including endoscopic and histological definitions of BE and early EAC; prevalence, incidence, natural history, and risk factors for BE; and methods for managing BE and early EAC. The latter considered modification of lifestyle factors; screening and surveillance strategies; and medical, endoscopic, and surgical interventions. To answer each question, the working party systematically reviewed the literature and developed a set of recommendations through consensus. Evidence underpinning each recommendation was rated according to quality and applicability.

Background Cathepsin E (CTSE), an aspartic proteinase, is differentially expressed in the metaplasia–dysplasia–neoplasia sequence of gastric and colon cancer. We evaluated CTSE in Barrett’s esophagus (BE) and cancer because increased CTSE levels are linked to improved survival in several cancers, and other cathepsins are up-regulated in BE and esophageal adenocarcinoma (EAC). Methods A total of 273 pretreatment tissues from 199 patients were analyzed [31 normal squamous esophagus (NE), 29 BE intestinal metaplasia, 31 BE with dysplasia (BE/D), 108 EAC]. CTSE relative mRNA expression was measured by real-time polymerase chain reaction, and protein expression was measured by immunohistochemistry. CTSE serum levels were determined by enzyme-linked immunosorbent assay. Results Median CTSE mRNA expression levels were ≥1,000-fold higher in BE/intestinal metaplasia and BE/D compared to NE. CTSE levels were significantly lower in EAC compared to BE/intestinal metaplasia and BE/D, but significantly higher than NE levels. A similar expression pattern was present in immunohistochemistry, with absent staining in NE, intense staining in intestinal metaplasia and dysplasia, and less intense EAC staining. CTSE serum analysis did not discriminate patient groups. In a uni- and multivariable Cox proportional hazards model, CTSE expression was not significantly associated with survival in patients with EAC, although CTSE expression above the 25th percentile was associated with a 41 % relative risk reduction for death (hazard ratio 0.59, 95 % confidence interval 0.27–1.26, p = 0.17). Conclusions CTSE mRNA expression is up-regulated more than any known gene in Barrett intestinal metaplasia and dysplasia tissues. Protein expression is similarly highly intense in intestinal metaplasia and dysplasia tissues. Electronic supplementary material The online version of this article (doi:10.1245/s10434-014-4155-y) contains supplementary material, which is available to authorized users.

Barrett's esophagus (BE), a common condition, is the only known precursor to esophageal adenocarcinoma (EAC). There is uncertainty about the best way to manage BE as most people with BE never develop EAC and most patients diagnosed with EAC have no preceding diagnosis of BE. Moreover, there have been recent advances in knowledge and practice about the management of BE and early EAC. To aid clinical decision making in this rapidly moving field, Cancer Council Australia convened an expert working party to identify pertinent clinical questions. The questions covered a wide range of topics including endoscopic and histological definitions of BE and early EAC; prevalence, incidence, natural history, and risk factors for BE; and methods for managing BE and early EAC. The latter considered modification of lifestyle factors; screening and surveillance strategies; and medical, endoscopic, and surgical interventions. To answer each question, the working party systematically reviewed the literature and developed a set of recommendations through consensus. Evidence underpinning each recommendation was rated according to quality and applicability.

Background: Endoscopic treatment by either radiofrequency (RFA) ablation or endoscopic mucosal resection (EMR) has become first line treatment for Barrett's esophagus (BE) with high grade dysplasia, while focal EMR and subsequent elimination of the residual segment by RFA or EMR is accepted therapy for intramucosal cancer (IMC). RFA and EMR are known to be clinically effective but the effect on the mRNA expression of molecular markers of disease stage, which may inform the long term risk of progression to adenocarcinoma, is unknown. We compared the mRNA expression profile in pre-treatment BE tissues biopsies and post-treatment neo-squamous tissues from the same level to provide a surrogatemolecular estimate of treatment effect. Methods: Paired pre-treatment BE tissues and post-treatment neosquamous biopsies were obtained from 38 patients treated by RFA (20 patients (3 IMC (prior EMR), 5 HGD, 12 LGD) or EMR (18 patients, 6 IMC, 12 HGD). mRNA expression of 16 genes significantly associated with different BE stages was measured using a multiplex tandem RT-PCR method with preand post-treatment tissues assessed simultaneously. Distal esophageal tissues from 12 patients with no history of GERD or BE were used as normal controls. Results: Endoscopic therapy resulted in a highly significant change in median values towards the normal squamous mucosa expression profile for all 16 genes on unpaired analysis. This change remained significant for 12 genes by paired analysis (t test). The only significant treatment differences in pre-post mean difference in gene expression were greater changes for RFA compared to EMR for 5 genes. The neosquamous expression profile was significantly different to the normal control profile for 9 of 16 genes. Conclusions: Both RFA and EMR result in marked changes in mRNA expression, with replacement of the highly disordered Barrett's dysplasia or IMC expression profile with a more "normal" expression profile. The neosquamous mucosa was significantly different to the normal control squamous mucosa for most genes but the significance of this finding is uncertain and may reflect confounding factors.

Background Alterations in gastrointestinal, pancreatic, and adipose hormone levels may have a greater role in weight loss than initially appreciated. The laparoscopic sleeve gastrectomy (LSG) operation is now the most frequently performed bariatric operation in many countries, but there are relatively few data regarding its molecular effects. We sought to characterize the effect of LSG on fasting plasma levels of selected hormones and on non-esterified fatty acids (NEFA), and to compare these to levels in non-obese control individuals. Materials and Methods The levels of nine plasma hormones were measured using a multiplex bead-based assay at baseline and at 3 months after operation in 11 obese patients undergoing LSG. NEFA levels were also measured. The levels were compared to those for 22 age- and sex-matched non-obese individuals. Results At baseline, obese patients showed significantly higher expression of C-peptide, insulin, and leptin and significantly lower ghrelin, glucose-dependent insulinotropic peptide (GIP), and resistin compared to non-obese controls (p