Studies of the invasiveness of the chemically induced mouse sarcoma FS9. I. monoclonal antibodies to a 37,000 dalton membrane glycoprotein inhibit invasion of fibroblasts in vitro

Abstract

Monoclonal antibodies against the mouse sarcoma FS9 were prepared. Antibodies recognizing a 37,000 dalton glycoprotein on FS9 tumor cells inhibit invasion by FS9 sarcoma cells of chicken heart fibroblasts in vitro as assessed by Abercrombie's confronted explant assay. Antibodies to other membrane proteins of FS9 tumor cells failed to inhibit invasiveness of FS9 sarcoma cells. The 37,000 dalton glycoprotein, which is neither a histocompatibility antigen nor a gp37 glycoprotein of Rous sarcoma virus nor the MEP described by Gottesman, is present on the surface and in the cytoplasm of FS9 sarcoma cells. The plasma membrane of the non-invasive mouse cell line L929 contains only low concentrations of the 37,000 dalton antigen. Hence, a relationship apparently exists between the increased concentration of this protein on the surface of FS9 cells and their invasiveness.

p37 from Mycoplasma hyorhinis promotes cancer cell invasiveness and metastasis through activation of MMP-2 and followed by phosphorylation of EGFR

“…One aspect is the elevated tumor invasion, as suggested by a leukocyte adherence inhibition response, correlated with the presence of M. hyorhinis in patients with lung cancer, colon cancer, and breast cancer (26). Additionally, two independent groups showed that surface expression of p37 in FS9 mouse fibrosarcoma cells was associated with a highly invasive phenotype as measured in the in vitro invasion assay (8,10,27). Antibody against p37 inhibited the invasive potential of infected FS9 cells in the in vitro assay (10,26).…”

Structural Insights into the Extracytoplasmic Thiamine-Binding Lipoprotein p37 of Mycoplasma hyorhinis

“…Cypl's role in mycoplasma infection has never been addressed. As for its effect on cancer cells, it has been shown that Cypl alone is sufficient to cause increased tumor invasivity, to the same degree as whole mycoplasma (26,48,49). Perhaps in vivo Cypl is involved in the transport of thiamine into the mycoplasma, which may sequester thiamine away from surrounding host cells, weakening them and creating an opportunity for infection.…”

“…hyorhinis p37 was originally identified as a 37-kDa protein that induced invasiveness in mouse sarcoma cells. This invasivity could be reversed if the cells were pretreated with the antibody to this protein (48,49). Several years later, a study was conducted on patients immunized intralymphatically with their own surgically debulked tumors looking for antibodies that induced remission and their associated antigens.…”

“…Since p37 was identified, several studies have indicated a correlation between the bacterium M. hyorhinis and gastric carcinoma, colon carcinoma, esophageal cancer, and lung cancer (23,41). p37 alone is sufficient to increase the invasivity of cancer cells (26,48,49). It has also been shown that p37 may also be associated with cancer malignancy and metastasis (20,21,28).…”

p37 induces tumor invasiveness

“…Additionally, two independent research groups showed that p37 on the surface of FS9 mouse fibrosarcoma cells was associated with a highly invasive phenotype, as measured in an in vitro cellular invasion assay (22,23). Furthermore, antibodies against p37 inhibited the invasive potential of infected FS9 cells in the in vitro assay (22,23), and reduced the lung metastasis of colon cancer in nude mouse models (24).…”