The 67-LR plays a major role in mediating high affinity
interactions between laminin and both normal and cancer
cells. The dramatic up-regulation of the 67-LR in a wide
variety of neoplasms, including breast and colon carcinoma,
has been clearly established in numerous studies at both the
protein and mRNA levels (15-20). Our ultimate objective is
to better assess the role of the 67-LR in the oncogenic process
by elucidating the biochemical mechanisms involved in 67-
LR-laminin interactions. Although originally identified in
1983 by several independent groups (4, 12, 13), the exact
structure and specific mechanisms of action of the 67-LR
have not been elucidated to date. Advances in the understanding
of the structure of the 67-LR have been hampered mainly
by the difficulty in purifying the protein in sufficient quantity
to permit extensive amino acid sequencing. The rationale of
the current study was to identify and characterize potential