Project description:Background: Gene expression profiling has been used extensively within breast cancer research. Patient matched transcriptomic studies of tumour samples before and after treatment offer great potential and have been initiated, but tend not to include a control group. Here we examine gene expression changes between patient-matched core biopsies and surgical resection samples in the absence of treatment, to consider sampling methods and tumour heterogeneity. Patients and Methods: Illumina BeadArray technology was used to measure dynamic changes in gene expression from thirty-seven paired baseline and surgically excised breast tumour samples obtained from women receiving no treatment prior to surgery. Results: Patient-matched sample pairs had significantly higher correlations than samples between different individuals, demonstrating that tumour heterogeneity and intra-tumour differences are less prominent than inter-tumour/patient differences. Perhaps surprisingly, consistent changes in gene expression were identified during the diagnosis-surgery interval, despite a lack of treatment. 50 genes were significantly differentially expressed (48 up, 2 down; FDR 0.05) in a manner that appears independent of both subtype and the sampling-interval length. Gene set enrichment analysis using four independent treated datasets has implicated the tumour sampling method as the likely cause of these expression changes which include increases in early growth response genes such as EGR1, 2 and 3 along with DUSP1 and FOS. Our data does not support the idea that there is a significant wounding or immune response. Conclusion: This is the largest cohort of patient-matched transcriptome profiling of tumours from patients receiving no treatment between diagnosis and surgery to date. It has revealed that consistent changes in gene expression do exist between diagnostic core biopsy and the surgical excision sample. We have confirmed these findings in a number of published breast cancer datasets. Ultimately, researchers should be aware of the potential for the tumour sampling method to introduce a confounding factor in future neoadjuvant studies. 37 paired patient-matched whole-transcriptome profiled primary breast tumours from patients receiving no treatment between diagnosis and surgery. Superseries is a product of two integrated individual batches.
Project description:Background: Gene expression profiling has been used extensively within breast cancer research. Patient matched transcriptomic studies of tumour samples before and after treatment offer great potential and have been initiated, but tend not to include a control group. Here we examine gene expression changes between patient-matched core biopsies and surgical resection samples in the absence of treatment, to consider sampling methods and tumour heterogeneity. Patients and Methods: Illumina BeadArray technology was used to measure dynamic changes in gene expression from thirty-seven paired baseline and surgically excised breast tumour samples obtained from women receiving no treatment prior to surgery. Results: Patient-matched sample pairs had significantly higher correlations than samples between different individuals, demonstrating that tumour heterogeneity and intra-tumour differences are less prominent than inter-tumour/patient differences. Perhaps surprisingly, consistent changes in gene expression were identified during the diagnosis-surgery interval, despite a lack of treatment. 50 genes were significantly differentially expressed (48 up, 2 down; FDR 0.05) in a manner that appears independent of both subtype and the sampling-interval length. Gene set enrichment analysis using four independent treated datasets has implicated the tumour sampling method as the likely cause of these expression changes which include increases in early growth response genes such as EGR1, 2 and 3 along with DUSP1 and FOS. Our data does not support the idea that there is a significant wounding or immune response. Conclusion: This is the largest cohort of patient-matched transcriptome profiling of tumours from patients receiving no treatment between diagnosis and surgery to date. It has revealed that consistent changes in gene expression do exist between diagnostic core biopsy and the surgical excision sample. We have confirmed these findings in a number of published breast cancer datasets. Ultimately, researchers should be aware of the potential for the tumour sampling method to introduce a confounding factor in future neoadjuvant studies. 37 paired patient-matched whole-transcriptome profiled primary breast tumours from patients receiving no treatment between diagnosis and surgery. Superseries is a product of two integrated individual batches.
Project description:Background: Gene expression profiling has been used extensively within breast cancer research. Patient matched transcriptomic studies of tumour samples before and after treatment offer great potential and have been initiated, but tend not to include a control group. Here we examine gene expression changes between patient-matched core biopsies and surgical resection samples in the absence of treatment, to consider sampling methods and tumour heterogeneity. Patients and Methods: Illumina BeadArray technology was used to measure dynamic changes in gene expression from thirty-seven paired baseline and surgically excised breast tumour samples obtained from women receiving no treatment prior to surgery. Results: Patient-matched sample pairs had significantly higher correlations than samples between different individuals, demonstrating that tumour heterogeneity and intra-tumour differences are less prominent than inter-tumour/patient differences. Perhaps surprisingly, consistent changes in gene expression were identified during the diagnosis-surgery interval, despite a lack of treatment. 50 genes were significantly differentially expressed (48 up, 2 down; FDR 0.05) in a manner that appears independent of both subtype and the sampling-interval length. Gene set enrichment analysis using four independent treated datasets has implicated the tumour sampling method as the likely cause of these expression changes which include increases in early growth response genes such as EGR1, 2 and 3 along with DUSP1 and FOS. Our data does not support the idea that there is a significant wounding or immune response. Conclusion: This is the largest cohort of patient-matched transcriptome profiling of tumours from patients receiving no treatment between diagnosis and surgery to date. It has revealed that consistent changes in gene expression do exist between diagnostic core biopsy and the surgical excision sample. We have confirmed these findings in a number of published breast cancer datasets. Ultimately, researchers should be aware of the potential for the tumour sampling method to introduce a confounding factor in future neoadjuvant studies.
Project description:Background: Gene expression profiling has been used extensively within breast cancer research. Patient matched transcriptomic studies of tumour samples before and after treatment offer great potential and have been initiated, but tend not to include a control group. Here we examine gene expression changes between patient-matched core biopsies and surgical resection samples in the absence of treatment, to consider sampling methods and tumour heterogeneity. Patients and Methods: Illumina BeadArray technology was used to measure dynamic changes in gene expression from thirty-seven paired baseline and surgically excised breast tumour samples obtained from women receiving no treatment prior to surgery. Results: Patient-matched sample pairs had significantly higher correlations than samples between different individuals, demonstrating that tumour heterogeneity and intra-tumour differences are less prominent than inter-tumour/patient differences. Perhaps surprisingly, consistent changes in gene expression were identified during the diagnosis-surgery interval, despite a lack of treatment. 50 genes were significantly differentially expressed (48 up, 2 down; FDR 0.05) in a manner that appears independent of both subtype and the sampling-interval length. Gene set enrichment analysis using four independent treated datasets has implicated the tumour sampling method as the likely cause of these expression changes which include increases in early growth response genes such as EGR1, 2 and 3 along with DUSP1 and FOS. Our data does not support the idea that there is a significant wounding or immune response. Conclusion: This is the largest cohort of patient-matched transcriptome profiling of tumours from patients receiving no treatment between diagnosis and surgery to date. It has revealed that consistent changes in gene expression do exist between diagnostic core biopsy and the surgical excision sample. We have confirmed these findings in a number of published breast cancer datasets. Ultimately, researchers should be aware of the potential for the tumour sampling method to introduce a confounding factor in future neoadjuvant studies.
2016-08-08 | GSE76726 | GEO
Project description:Optimisation of the sampling method for skin microbiome studies
Project description:The NEWEST (Neoadjuvant Endocrine Therapy for Women with Estrogen-Sensitive Tumours) trial compared the clinical and biological activity of fulvestrant 500 mg vs 250 mg in the neoadjuvant setting. In this multi-centre phase II study, post-menopausal women with operable, locally advanced (T2, 3, 4b; N0-3; M0) ER-positive breast tumours were randomised to receive neoadjuvant treatment with either dose of fulvestrant for 16 weeks before surgery. Tumour core biopsies were obtained at baseline, 4 weeks and at surgery for assessment of changes in biomarker expression. Tumour volumes were measured by 3-D ultrasound at the same timepoints. In this trial, the percentage of patients who showed a reduction in tumour volume or stabilisation of disease (using RECIST criteria) after treatment with fulvestrant 500 mg was 36% (26 out of 69 patients). Therefore, within a population of endocrine-therapy naive patients whose tumours were confirmed as being ER-positive at the time of study entry, there is a subgroup who gained particular clinical benefit from fulvestrant treatment. These clinical response data together with the availability of biological response information and frozen tumour tissue from participants makes the NEWEST trial an attractive setting in which to investigate the potential of new markers of response to fulvestrant. 42 samples
Project description:We performed whole transcriptome RNA sequencing on serial tumour biopsies collected at baseline, Day 14, and after completion of all neoadjuvant therapy from the NA-PHER2 trial. Patients received neoadjuvant treatment with the combined regimen of trastuzumab, pertuzumab, palbociclib with or without addition of fulvestrant. Transcriptomic profiles were generated from 143 samples (Baseline n = 53, Day 14 n = 49, Surgery n = 41) corresponding to 55 of the 58 patients enrolled in NA-PHER2 trial (94.8%). RNA sequencing was performed on total RNA samples derived from formalin-fixed, paraffin-embedded (FFPE) tissue sections. RNA-Seq libraries were produced using NEBNext® Ultra™ II Directional RNA Library Prep Kit. The capture was then performed on cDNA libraries with the Twist Human Core Exome Enrichment System according to supplier recommendations (Twist Bioscience). The obtained eluted-enriched DNA samples was then sequenced on an Illumina NovaSeq as paired-end 100bp reads.
Project description:The NEWEST (Neoadjuvant Endocrine Therapy for Women with Estrogen-Sensitive Tumours) trial compared the clinical and biological activity of fulvestrant 500 mg vs 250 mg in the neoadjuvant setting. In this multi-centre phase II study, post-menopausal women with operable, locally advanced (T2, 3, 4b; N0-3; M0) ER-positive breast tumours were randomised to receive neoadjuvant treatment with either dose of fulvestrant for 16 weeks before surgery. Tumour core biopsies were obtained at baseline, 4 weeks and at surgery for assessment of changes in biomarker expression. Tumour volumes were measured by 3-D ultrasound at the same timepoints. In this trial, the percentage of patients who showed a reduction in tumour volume or stabilisation of disease (using RECIST criteria) after treatment with fulvestrant 500 mg was 36% (26 out of 69 patients). Therefore, within a population of endocrine-therapy naive patients whose tumours were confirmed as being ER-positive at the time of study entry, there is a subgroup who gained particular clinical benefit from fulvestrant treatment. These clinical response data together with the availability of biological response information and frozen tumour tissue from participants makes the NEWEST trial an attractive setting in which to investigate the potential of new markers of response to fulvestrant.