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Updated: Jun 26, 2026
Colorectal Cancer Cell Surface Protein Profiling Using an Antibody Microarray and Fluorescence Multiplexing
Published on: September 25, 2011
Label-free nLC-MS/MS proteomic analysis reveals significant differences in the proteome between colorectal cancer
Sezgin Zeren1, Semih Seker2, Gizem Akkaş Akgün3
1Department of General Surgery, Faculty of Medicine, Kutahya Health Sciences University, Kutahya, Turkey.
Abstract:
Despite the discovery of numerous driving and passenger genes that play key roles in cancer characteristics, progress in cancer treatment has not been satisfactory. This is mainly because conventional therapies are neither selective nor targeted. Another important reason is that cancer cells rapidly develop resistance to chemotherapeutic agents due to excessive accumulation of mutations and/or epigenetic changes. In light of this, we believe that the discovery of new targets and key genes/proteins could improve treatment options. In this study, tissue samples (tumor and normal mucosa) were first collected from the colon or rectum by right or left hemicolectomy. Proteomic analysis was then performed using the label-free nLC-MS/MS method. We determined 77 proteins with statistically significant differences in expression levels between cancerous and normal mucosa. While the expression of 76 proteins was decreased in cancer tissues, only one protein (RNA-binding motif protein_X chromosome-RBMX) was increased in colorectal cancer tissues. The bioinformatics portal Metascape was used to determine the biological processes involved. 77 proteins with significantly different expression between cancerous and normal tissues were compared with the UALCAN platform using data from the Clinical Proteomics Tumor Analysis Consortium (CPTAC). The results for 45 of the 77 proteins clearly matched the CPTAC dataset. Western blot studies confirmed that RBMX protein (critical for gene transcription and alternative splicing of various pre-mRNAs) was increased 2.04-fold, while decorin protein (a matrix proteoglycan with tumor suppressor functions) was dramatically decreased by about 6.04-fold in tumor samples compared with normal mucosa.
Insights
This study identified 77 differentially expressed proteins in colorectal cancer, with RNA-binding motif protein (RBMX) elevated and decorin decreased. These findings may offer new therapeutic targets for improved cancer treatment.
Area of Science:
- Proteomics
- Molecular Biology
- Oncology
Background:
- Conventional cancer therapies lack selectivity and are hampered by rapid drug resistance.
- Identifying novel molecular targets is crucial for advancing cancer treatment options.
Purpose of the Study:
- To identify differentially expressed proteins in colorectal cancer (CRC) tissues compared to normal mucosa.
- To investigate potential new biomarkers and therapeutic targets for CRC.
Main Methods:
- Proteomic analysis using label-free nLC-MS/MS on paired tumor and normal colorectal tissue samples.
- Bioinformatic analysis with Metascape and UALCAN platform, utilizing Clinical Proteomics Tumor Analysis Consortium (CPTAC) data.
- Validation of key protein expression changes using Western blot.
Main Results:
- Identified 77 proteins with significant expression differences between CRC and normal tissues.
- RNA-binding motif protein (RBMX) expression was increased 2.04-fold in tumors.
- Decorin expression was significantly decreased by approximately 6.04-fold in tumors.
- 45 of the 77 identified proteins showed concordance with CPTAC dataset.
Conclusions:
- The study highlights significant proteomic alterations in colorectal cancer.
- Elevated RBMX and decreased decorin are key findings, suggesting their potential roles in CRC pathogenesis.
- These proteins represent promising targets for future colorectal cancer diagnostics and therapeutics.
