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Direct Bioprinting of 3D Multicellular Breast Spheroids onto Endothelial Networks
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Alterations in integrin and basement-membrane protein expression by malignant breast cells
1NORTHWESTERN UNIV,CTR CANC,SCH MED,DEPT MED,DIV HEMATOL ONCOL,CHICAGO,IL 60611.
International Journal of Oncology
|May 14, 2011
Summary
Breast cancer cells show altered expression of adhesion molecules and basement membrane proteins. These changes in integrins and ligands are not genetic and can be studied in cell cultures.
Area of Science:
- Cell Biology
- Oncology
- Biochemistry
Background:
- Integrins are crucial cell adhesion receptors involved in cell-matrix and cell-cell interactions.
- Basement membrane proteins provide structural support and signaling cues to epithelial cells.
- Altered expression of these molecules is implicated in cancer progression and metastasis.
Purpose of the Study:
- To investigate the expression patterns of integrin subunits and basement membrane proteins in normal and malignant human mammary epithelial cells (HMEC).
- To compare the expression of these molecules in cells cultured in vitro versus cells within tissue sections (in vivo).
- To determine if observed expression changes in breast carcinomas are genetic or related to altered regulation.
Main Methods:
- Immunohistochemistry was used to analyze protein expression in tissue sections.
- Cell culture techniques were employed to study HMEC in vitro.
- Expression levels of eight integrin subunits and four basement membrane proteins were quantified.
Main Results:
- Normal HMEC expressed six integrin subunits consistently in culture and in vivo.
- Malignant HMEC showed altered expression of certain integrins (e.g., loss of alpha1, absence of beta4) in vivo, but these changes were reversible in culture, indicating non-genetic regulation.
- Expression of integrin subunits was not directly correlated with their basement membrane protein ligands.
- Differences in basement membrane protein expression were observed between normal and malignant cells, and between in vivo and in vitro conditions.
Conclusions:
- Breast carcinoma cells exhibit dysregulated expression of adhesion receptors (integrins) and their ligands.
- These alterations in expression are not genetically determined and can be modulated in cell culture models.
- Further studies using cultured HMEC can provide insights into the aberrant regulation of cell adhesion in breast cancer.
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