Exogenous fibronectin requirement for adhesion by neoplastic human cells

Area of Science:

• Cell biology
• Biochemistry
• Cancer research

Background:

• Cell surface fibronectin levels differ between normal and neoplastic human cells.
• Neoplastic and transformed cells exhibit reduced or absent surface fibronectin.
• Cell spreading behavior is influenced by extracellular matrix components.

Purpose of the Study:

• To investigate the role of serum, plasma, and plasma fibronectin in human cell spreading.
• To compare the spreading behavior of normal, virus-transformed, and neoplastic human cells.
• To elucidate the dependency of neoplastic cells on fibronectin for adhesion.

Main Methods:

• Quantitative cell spreading assay.
• Use of normal and neoplastic human cell lines.
• Immunofluorescence technique to detect intercellular fibronectin.

Main Results:

• Normal human cells spread without serum or exogenous fibronectin due to abundant surface fibronectin.
• Neoplastic and virus-transformed cells require serum or plasma for spreading, indicating fibronectin dependency.
• Neoplastic cells can utilize fibronectin from coated substrata or directly from the medium.
• The ability of transformed cells to recruit fibronectin correlates with intercellular fibronectin presence.

Conclusions:

• Fibronectin is a key factor mediating the spreading of neoplastic and transformed cells.
• Neoplastic cells may depend on extracellular fibronectin for in vivo adherence.
• The degree of fibronectin dependency can vary among different neoplastic cell types.