TY - JOUR
T1 - Application of the dual-micropipet technique to the measurement of tumor cell locomotion
AU - You, Jun
AU - Mastro, Andrea M.
AU - Dong, Cheng
N1 - Funding Information:
The authors thank Dr. Roger Gaumond at Penn State University for many helpful discussions. We also acknowledge Dr. Hynda Klein-man at NIH for providing the laminin proteins. This work was supported in part by the National Science Foundation (BES-9502069), the American Cancer Society (JFRA-535), and the National Institutes of Health (CA-76434).
PY - 1999/4/10
Y1 - 1999/4/10
N2 - The objective of this work was to characterize tumor cell locomotion in response to chemotactic stimulation using a dual-micropipet assay. The assay involves two micropipets. An individual A2058 human melanoma cell was retained, without pressure gradient, in a pipet of approximately 14 μm i.d. A solution of type IV collagen, chosen as the chemotactic source, was placed in another pipet (~10 μm o.d.) with zero pressure at the pipet tip. The smaller pipet was then inserted into the larger one containing the melanoma cell. The initial chemoattractant concentration (C(o)) and the distance between the tip of the small pipet and the cell surface (δ) provided a gradient (C(o)/δ) for tumor cell locomotion toward stimulation. This novel assay provides a direct measure of cell movement: cyclic pseudopod protrusion (L(p)) and subsequent cell locomotion (L(o)). The influences of different adhesion substrates on cell locomotion were also studied. The peak length in L(p) precedes the highest locomotion velocity (dL(c)/dt) by an apparent lag time. C(o)/δ influences pseudopod protrusion frequency (f(p)) and dL(c)/dt, but not significantly on L(p). Substrate adhesions affect dL(c)/dt, but apparently not L(p) or f(p). In conclusion, pseudopod protrusion and substrate adhesion are two necessary but mutually independent factors in tumor cell locomotion, dL(c)/dt correlates with changes in C(o)/δ, which is in significant correlation with f(p) but not L(p).
AB - The objective of this work was to characterize tumor cell locomotion in response to chemotactic stimulation using a dual-micropipet assay. The assay involves two micropipets. An individual A2058 human melanoma cell was retained, without pressure gradient, in a pipet of approximately 14 μm i.d. A solution of type IV collagen, chosen as the chemotactic source, was placed in another pipet (~10 μm o.d.) with zero pressure at the pipet tip. The smaller pipet was then inserted into the larger one containing the melanoma cell. The initial chemoattractant concentration (C(o)) and the distance between the tip of the small pipet and the cell surface (δ) provided a gradient (C(o)/δ) for tumor cell locomotion toward stimulation. This novel assay provides a direct measure of cell movement: cyclic pseudopod protrusion (L(p)) and subsequent cell locomotion (L(o)). The influences of different adhesion substrates on cell locomotion were also studied. The peak length in L(p) precedes the highest locomotion velocity (dL(c)/dt) by an apparent lag time. C(o)/δ influences pseudopod protrusion frequency (f(p)) and dL(c)/dt, but not significantly on L(p). Substrate adhesions affect dL(c)/dt, but apparently not L(p) or f(p). In conclusion, pseudopod protrusion and substrate adhesion are two necessary but mutually independent factors in tumor cell locomotion, dL(c)/dt correlates with changes in C(o)/δ, which is in significant correlation with f(p) but not L(p).
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U2 - 10.1006/excr.1999.4388
DO - 10.1006/excr.1999.4388
M3 - Article
C2 - 10094823
AN - SCOPUS:0033541406
SN - 0014-4827
VL - 248
SP - 160
EP - 171
JO - Experimental Cell Research
JF - Experimental Cell Research
IS - 1
ER -