Dataset Information

Plasma protein expression differs between colorectal cancer patients depending on primary tumor location.

ABSTRACT: Colorectal cancer (CRC) includes tumors in the right colon, left colon, and rectum, although they differ significantly from each other in aspects such as prognosis and treatment. Few previous mass spectrometry-based studies have analyzed differences in protein expression depending on the tumor location. In this study, we have used mass spectrometry-based proteomics to analyze plasma samples from 83 CRC patients to study if differences in plasma protein expression can be seen depending on primary tumor location (right colon, left colon, or rectum). Differences were studied between the groups both regardless of and according to tumor stage (II or III). Large differences in plasma protein expression were seen, and we found that plasma samples from patients with rectal cancer separated from samples from patients with colon cancer when analyzed by principal component analysis and hierarchical clustering. Samples from patients with cancer in the right and left colon also tended to separate from each other. Pathway analysis discovered canonical pathways involved in lipid metabolism and inflammation to be enriched. This study will help to further define CRC as distinct entities depending on tumor location, as shown by the widespread differences in plasma protein profile and dysregulated pathways.

SUBMITTER: Holm M

PROVIDER: S-EPMC7367633 | biostudies-literature | 2020 Jul

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Plasma protein expression differs between colorectal cancer patients depending on primary tumor location.

Holm Matilda M Joenväärä Sakari S Saraswat Mayank M Tohmola Tiialotta T Ristimäki Ari A Renkonen Risto R Haglund Caj C

Cancer medicine 20200526 14

Colorectal cancer (CRC) includes tumors in the right colon, left colon, and rectum, although they differ significantly from each other in aspects such as prognosis and treatment. Few previous mass spectrometry-based studies have analyzed differences in protein expression depending on the tumor location. In this study, we have used mass spectrometry-based proteomics to analyze plasma samples from 83 CRC patients to study if differences in plasma protein expression can be seen depending on primary ...[more]

PMID: 32452655

Similar Datasets

Project description:BackgroundIntra-tumor heterogeneity (ITH) of colorectal cancer (CRC) complicates molecular tumor classification, such as transcriptional subtyping. Differences in cellular states, biopsy cell composition, and tumor microenvironment may all lead to ITH. Here we analyze ITH at the transcriptomic and proteomic levels to ascertain whether subtype discordance between multiregional biopsies reflects relevant biological ITH or lack of classifier robustness. Further, we study the impact of tumor location on ITH.MethodsMultiregional biopsies from stage II and III CRC tumors were analyzed by RNA sequencing (41 biopsies, 14 tumors) and multiplex immune protein analysis (89 biopsies, 29 tumors). CRC subtyping was performed using consensus molecular subtypes (CMS), CRC intrinsic subtypes (CRIS), and TUMOR types. ITH-scores and network maps were defined to determine the origin of heterogeneity. A validation cohort was used with one biopsy per tumor (162 tumors).ResultsOverall, inter-tumor transcriptional variation exceeded ITH, and subtyping calls were frequently concordant between multiregional biopsies. Still, some tumors had high transcriptional ITH and were classified discordantly. Subtyping of proximal MSS tumors were discordant for 50% of the tumors, this ITH was related to differences in the microenvironment. Subtyping of distal MSS tumors were less discordant, here the ITH was more cancer-cell related. The subtype discordancy reflected actual molecular ITH within the tumors. The relevance of the subtypes was reflected at protein level where several inflammation markers were significantly increased in immune related transcriptional subtypes, which was verified in an independent cohort (Wilcoxon rank sum test; p<0.05). Unsupervised hierarchical clustering of the protein data identified large ITH at protein level; as the multiregional biopsies clustered together for only 9 out of 29 tumors.ConclusionOur transcriptomic and proteomic analyses show that the tumor location along the colorectum influence the ITH of CRC, which again influence the concordance of subtyping.

Project description:STUDY QUESTION:What is the correlation of serum anti-Müllerian hormone (AMH) levels between two frequently used laboratory assays? SUMMARY ANSWER:A considerable difference was found in serum AMH levels measured with the two different assays, particularly for low AMH values. WHAT IS KNOWN ALREADY:AMH is regarded as being a robust, highly sensitive and specific biomarker for ovarian response and has become widely used as the basis for fertility treatment decisions. However, several available assays with different reference values, in addition to inter-laboratory variations and issues of sample stability, make interpretation of the AMH values and their clinical implications complicated. STUDY DESIGN SIZE DURATION:An observational study was performed including 269 serum samples from infertile women, originating from a RCT conducted in 2013-2016 (www.clinicaltrials.gov NCT02013973). PARTICIPANTS/MATERIALS SETTING METHOD:Serum AMH levels analysed with the Modified Beckman Coulter Gen II ELISA assay (Premix method) were compared to AMH levels analysed with the Beckman Coulter Gen II ELISA original assay (Gen II original). All samples were handled identically and analysed with the two assays in a parallel setting. MAIN RESULTS AND THE ROLE OF CHANCE:The slope of the regression line showed a mean of 18% higher values with the Premix method compared to the Gen II original assay, and more than 40% higher values for AMH levels in the lower range. LIMITATIONS REASONS FOR CAUTION:The Gen II original assay is no longer in clinical use as it has been replaced by the Premix method, which, in turn, recently has been further developed into an automated method. WIDER IMPLICATIONS OF THE FINDINGS:The finding of differences in AMH levels between assays is clinically important and may imply an incorrect classification in the assessment of ovarian reserve. The robustness of serum AMH as a marker for ovarian reserve and as a tool for fertility counselling has to be investigated further. There is an urgent need for international standards on interpretation of AMH values for different assays. STUDY FUNDING/COMPETING INTERESTS:Financial support was received through Sahlgrenska University Hospital (ALFGBG-70940) and the Hjalmar Svensson Research Foundation. None of the authors declares any conflict of interest.

Dataset Information

Plasma protein expression differs between colorectal cancer patients depending on primary tumor location.

Publications

Plasma protein expression differs between colorectal cancer patients depending on primary tumor location.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure