Compartment-Specific CD138 Expression Defines an Aggressive Breast Cancer Phenotype with Distinct Transcriptomic...

Area of Science:

• Oncology
• Molecular Biology
• Proteoglycan Research

Background:

• CD138 (syndecan-1) is a cell-surface proteoglycan implicated in tumor progression.
• The clinical significance of compartment-specific CD138 expression in breast cancer is not well understood.

Purpose of the Study:

• To investigate the prognostic and transcriptomic features of compartment-specific CD138 expression in invasive breast cancer.
• To determine if CD138 expression patterns in tumor and stromal compartments correlate with patient outcomes and molecular characteristics.

Main Methods:

• Integrated analysis of immunohistochemistry and RNA sequencing on 111 invasive ductal carcinoma specimens.
• Classification of tumors into four groups based on CD138 expression in tumor and stromal compartments.
• Analysis of clinicopathological data, survival outcomes, and transcriptomic profiles.

Main Results:

• A tumor-positive/stroma-negative CD138 phenotype (Group 1) was associated with significantly poorer recurrence-free survival.
• Group 1 was an independent prognostic factor for poor survival and linked to lymph node metastasis, HER2 expression, and brain metastases.
• Transcriptomic analysis of Group 1 tumors revealed upregulated small nucleolar RNAs and enriched pathways in ribosome biogenesis and RNA processing.

Conclusions:

• Compartment-specific CD138 expression defines an aggressive breast cancer phenotype with unique transcriptomic signatures.
• This CD138 expression pattern holds potential prognostic value for invasive breast cancer.
• Further validation in larger cohorts is warranted to confirm the clinical utility of this finding.