Tumor cell metastasis involves a complex series of events, including the adhesion, migration and invasive behavior of tumor cells on components of the extracellular matrix. Multiple cell surface receptors mediate interactions with the surrounding extracellular matrix and thereby influence cell adhesion, motility and invasion. We have previously described a cell surface CD44-related chondroitin sulfate proteoglycan on highly metastatic melanoma cells. CD44-chondroitin sulfate proteoglycan was shown to be important in melanoma cell motility and invasive behavior on type I collagen matrices. In our current studies, the role of cell surface CD44-chondroitin sulfate proteoglycan in collagen-mediated mouse melanoma cell migration and invasive behavior is further evaluated using transforming growth factor-beta 1. We report that transforming growth factor-beta 1 stimulates the migratory and invasive behavior of mouse melanoma cells on type I collagen. Transforming growth factor-beta 1 stimulated cell surface CD44-chondroitin sulfate proteoglycan synthesis in mouse melanoma cells, specifically through an upregulation of chondroitin sulfate production, while the expression of CD44-chondroitin sulfate proteoglycan core protein was not affected. Furthermore, transforming growth factor-beta 1-mediated enhancement of cell polarity, migration and invasive behavior on type I collagen gels was markedly inhibited in the presence of beta-D-xyloside, an agent that blocks chondroitin sulfate addition to the core protein. Collectively, our findings indicate that mouse melanoma cell surface CD44-chondroitin sulfate proteoglycan is required for transforming growth factor-beta 1-enhanced cell motility and invasion, and that CD44-chondroitin sulfate proteoglycan may play a role in forming and/or maintaining a dominant leading lamella, which is required for efficient locomotion.

The metastatic spread of tumor cells occurs through a complex series of events, one of which involves the adhesion of tumor cells to extracellular matrix (ECM) components. Multiple interactions between cell surface receptors of an adherent tumor cell and the surrounding ECM contribute to cell motility and invasion. The current studies evaluate the role of a cell surface chondroitin sulfate proteoglycan (CSPG) in the adhesion, motility, and invasive behavior of a highly metastatic mouse melanoma cell line (K1735 M4) on type I collagen matrices. By blocking mouse melanoma cell production of CSPG with p-nitrophenyl beta-D-xylopyranoside (beta-D-xyloside), a compound that uncouples chondroitin sulfate from CSPG core protein synthesis, we observed a corresponding decrease in melanoma cell motility on type I collagen and invasive behavior into type I collagen gels. Melanoma cell motility on type I collagen could also be inhibited by removing cell surface chondroitin sulfate with chondroitinase. In contrast, type I collagen-mediated melanoma cell adhesion and spreading were not affected by either beta-D-xyloside or chondroitinase treatments. These results suggest that mouse melanoma CSPG is not a primary cell adhesion receptor, but may play a role in melanoma cell motility and invasion at the level of cellular translocation. Furthermore, purified mouse melanoma cell surface CSPG was shown, by affinity chromatography and in solid phase binding assays, to bind to type I collagen and this interaction was shown to be mediated, at least in part, by chondroitin sulfate. Additionally we have determined that mouse melanoma CSPG is composed of a 110-kD core protein that is recognized by anti-CD44 antibodies on Western blots. Collectively, our data suggests that interactions between a cell surface CD44-related CSPG and type I collagen in the ECM may play an important role in mouse melanoma cell motility and invasion, and that the chondroitin sulfate portion of the proteoglycan seems to be a critical component in mediating this effect.

The metastatic spreadoftumorcellsoccurs througha complexseriesofevents,one ofwhichin- volvestheadhesionoftumorcellstoextracellular ma- trix(ECM) components.Multipleinteractions between cellsurfacereceptors ofanadherenttumor celland thesurroundingECM contribute tocellmotility and invasion .The currentstudiesevaluatetheroleofa cell surfacechondroitin sulfate proteoglycan (CSPG) inthe adhesion,motility, and invasive behaviorofa highly metastatic mouse melanoma cellline(K1735M4) on typeIcollagenmatrices .By blockingmouse melanoma cellproductionofCSPG withp-nitrophenyl s-D-xylo- pyranoside(s-D-xyloside), a compound thatuncouples chondroitin sulfate fromCSPG coreproteinsynthesis, we observeda corresponding decreaseinmelanoma cellmotility on typeIcollagenand invasive behavior intotypeI collagengels.Melanoma cellmotility on typeIcollagencouldalsobe inhibited by removing cellsurfacechondroitin sulfate withchondroitinase .In contrast, typeIcollagen-mediated melanoma cell

Studies of the diminished mitogen-induced proliferative response of T lymphocytes from older subjects show that aging must result in some defect(s) in the intracellular events required for transition from the G0 or quiescent state through the prereplicative interval and into the first S phase of the cell cycle. This conclusion is supported by observations of diminished inducibility of the lymphokine IL-2 and its receptor during aging. The current study demonstrates that decreased proliferative response to phytohemagglutinin (PHA) is also paralleled by decreased induction during the prereplicative interval of two of the most strongly enhanced proteins in mitogen-activated T cells: HSP90 and P73, which are also members of the heat-shock protein family. Diminished induction of HSP90 and P73 is observed in lymphocytes from older subjects (mean age 75), regardless of differences in health status of the subject populations. These results suggest that in vivo aging of human T cells results in a general defect in the induction of gene products required for transition from quiescence into the S phase of the cell cycle and that diminished T cell proliferation in advanced age is not due to a specific, "intrinsically immunologic" defect in induction of IL-2 and the IL-2 receptor.

Hemoglobin solutions were assessed in terms of their ability to promote lipid peroxidation, which was quantitated by measuring the formation of thiobarbituric acid reactive substances (TBARS) under specified conditions in murine brain homogenates. Solutions designed for use in acute treatment of hypovolemic shock and trauma should incorporate ingredients specifically aimed at decreasing oxygen and lipid radical mediated injury occurring secondary to ischemia and reperfusion. A number of strategies aimed at decreasing the oxidant effect of hemoglobin solutions and other blood and plasma substitutes have been evaluated. These include use of the naturally occurring anti-oxidants in human plasma, specifically transferrin and ceruloplasmin. Similarly, certain iron chelators, such as deferoxamine (Desferal, Ciba-Geigy), effectively prevent molecular and cellular damage caused by iron catalyzed formation of oxygen derived radicals.