Leukocyte migration inhibition among breast cancer patients in response to various oncogenic viruses.

The direct leukocyte migration inhibition (LMI) test was done with leukocytes from healthy women and from patients with primary operable breast cancer, benign breast disease, or head and neck cancer. Purified preparations of murine mammary tumor virus (MuMTV), Mason-Pfizer monkey virus (MPMV), and murine leukemia virus (MuLV) were used. For each virus, the lowest 10th percentile of the LMI responses of controls was used to discriminate positive from negative responses. Leukocytes from 46 of 94 (49%) breast cancer patients responded to MuMTV, which was significantly different from each of the other test groups: Positive reactions were observed in only 9 of 67 (13%) healthy persons, 2 of 32 (6%) patients with benign breast tumors, and 2 of 20 (10%) patients with head and neck cancer. Although leukocytes from 29% of the breast cancer patients responded to MPMV, this response did not significantly differ from that observed in healthy women (14%), in patients with benign disease (20%), or in patients with head and neck cancer (20%). The leukocytes from the breast cancer patients were not reactive to MuLV. LMI tests to both MuMTV and extracts of MCF-7 cultured breast cancer cells were done in 36 breast cancer patients and 40 healthy women simultaneously. Of the breast cancer patients, 75% responded to MuMTV and/or MCF-7 antigen as compared to 18% of the controls (P less than 0.005). These data suggest that leukocytes from breast cancer patients are presensitized to MuMTV and antigen(s) present in MCF-7 breast cancer cell line, but not to MPMV or MuLV.

The leukocyte migration inhibition response to certain breast cancer-related antigens (MCF-7 and MuMTV): their potential as discriminants.

Certain oncogenic viruses have been implicated in human breast cancer, including the murine mammary tumor virus (MuMTV) and the Mason-Pfizer monkey virus (MPMV). We have used the leukocyte migration inhibition (LMI) response to assay the response to several potential breast cancer-related antigens, including MuMTV, MPMV, and a breast cancer cultured cell line, MCF-7, in 96 breast cancer patients, in 32 women with benign breast disease, and in 67 normal women. The lowest tenth percentile of control (LMI) responses was used as the cutoff point to designate responders. Breast cancer patients showed significant responses to MuMTV (49% and to MCF-7 (50%), but not to MPMV (29%). In a paired-antigen study using MuMTV and MCF-7, 75% of the breast cancer patients responded, versus 18% of the normal women (P less than 0.0050). The potential for this assay to distinguish "normal" from "breast cancer" was analyzed using a migration index derived from discriminant analysis. The ability of the assay to discriminate "normal" from "cancer" was significant (P less than 0.001) and showed a sensitivity of detecting "cancer" of 75%. The overall responses to MuMTV and MCF-7 were analyzed with reference to certain prognostic factors, but showed no relation to age, menstrual status, estrogen receptor status, or stage of disease. The above reactions suggest that a large proportion of breast cancer patients exhibit presensitization to antigenfs found in MuMTV and MCF-7, which may be cross-reactive with antigens in the primary cancer. These responses appear to be independent of major prognostic variables. Further refinement of this assay may yield one which is more highly discriminating for breast cancer.