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TNF is an inflammatory cytokine that involved in pathogenesis of different malignancies. Promoter single nucleotide polymorphism -238(G/A)TNF (rs361525) is investigated for the detection of susceptibility to the infectious, autoimmune and oncological diseases. The goal of the study was to investigate the association of-238(G/A)TNF polymorphism (rs361525) with breast cancer (BC) prognosis. -238(G/A) TNF allelic variants were detected by PCR-RFLP. We failed to reveal the genotype distributions disparity among groups with different stages of the disease, ER, PR or Her2/neu positive versus negative status. The AG genotype frequency was about 10% and there were no BC patients with AA genotype in all separated groups. However the overall survival was significantly lower for AG then for GG carriers with II stage or ER-positive BC. Our data suggest that -238(G/A)TNF polymorphism perhaps is not involved in the initiation of malignancies but it is a substantial factor of BC prognosis.

Analysis of microsatellite TNFalpha marker and (-308(G/A) polymorphisms in promoter of TNFalpha gene was conducted in 167 patients with various types of sporadic breast cancer (BC) as well as in 139 healthy Russian donors. It was shown that frequency of allele 7 in TNFalpha microsatellite marker was significantly higher in BC patients than in healthy donors (17.9% versus 10.4%; P = 0.02) mainly due to the patients with invasive ductal BC (19.2% versus 10.4%; P = 0.008). The TNFalpha allele 9 was observed significantly more frequently in patients with invasive-ductal cancer (6.4% versus 1%; P= 0.01). The studies of-308(G/A)TNFalpha polymorphism in BC patients and healthy donors have shown no differences in the distribution frequency of highly secreted allele (-308A)TNFalpha. However, invasive lobular BC patients carrying (-308AG)TNFalpha genotype were observed significantly more frequently than invasive-ductal BC patients carrying the same allele (34.0 versus 17.3%; P = 0.034). Thus it has been shown for the first time that invasive-ductal and invasive-lobular BC patients differ in distribution of TNFalpha and -308(G/A)TNFalpha alleles.

A first attempt at investigating polymorphism of microsatellite TNFa and SNP-308 (G/A) in promoter of TNFalpha was made in patients with sporadic and hereditary breast cancer. 308 (A) TNFalpha and TNFa 12 alleles frequencies were significantly higher while that of TNFa10--significantly lower in the hereditary cancer group as compared with donors as well as sporadic cancer patients. That was contributed by cases of infiltrative-lobular tumors. Conversely, because of infiltrative-ductal tumors fraction, TNFa 7 allele frequency in sporadic cancer group was significantly higher than in donors and hereditary breast cancer patients. It was suggested that polymorphism of 308 (G/A) TNFalpha and TNFa depended, first of all, on patterns of breast and, secondly, on the elevated TNFalpha expression as a factor of pathogenesis of hereditary breast cancer.

The existence of retrovirus related to murine mammary tumor virus (MMTV) and specifically associated with mammary carcinoma has been suggested long ago. This review covers some papers published in the 70-80ies until now, containing evidence for this suggestion. In spite of a lack of direct proof of virus existence this problem still remains to be solved. There are some indications that both in man and in mice, peripheral blood lymphocytes participate in the circulation of the supposed viral agent.

Expression of DNA sequences homologous to sequences of env gene of mouse mammary tumor virus (MMTV) in the lymphocytes of patients with breast cancer and in subjects at a high risk of breast cancer has been reported. Antigen analogous to envelope protein gp52, product of MMTV env gene, is detected in T lymphocytes of virtually all patients with breast cancer and extremely rarely in T cells of controls, where its expression is confined to B cells. For explaining such unexpected results, we studied the molecular basis of this antigen synthesis. Specific PCR products were obtained using primers to gp52-coding region of MMTV env gene. One of them (957 nucleotides) was used as a probe for hybridization of DNA and RNA from lymphocytes of patients with breast cancer and controls. This sequence was hybridized with 90% frequency with genome DNA of breast cancer patients and with 85% frequency with genome RNA of such patients, which is almost 4-fold more than in the controls (patients with gynecological tumors or donors). These results correlate with the frequency of detection of the studied antigen in patients with breast cancer and control group patients.

Previously we reported that HMCAg related to gp52, env product of MMTV, was a specific marker of human breast cancer (BC). This antigen was expressed not only in BC tissue and patients' sera, but in peripheral T- and B-cells. HMCAg was found in 21.4% of healthy donors, but only in the fraction rich in B-cells. We searched for env-homologous sequences in BC patients by Northern and Southern dot-blot hybridization of plasmid clones containing env MMTV with total RNA and DNA of peripheral blood lymphocytes of BC patients, gynecological patients with hormone-dependent tumors, and donors. Transcription of DNA sequences related to env MMTV was revealed in 91.3% of BC patients, 22.2% gynecological patients, and 27.2% donors. In all cases except 1 donor and 1 gynecological patient this transcription correlated with HMCAg expression in lymphoid cells from the same subjects detected by indirect immunofluorescence with anti-gp52 MMTV rabbit serum. Analysis of in vitro translation products with poly(A) RNA as a template and immunoblotting method showed that at least one of the polypeptides formed corresponded to HMCAg by molecular weight and immunological reactivity, which fact appears to explain the correlation described above.

Incidence of sera with antibodies to MMTV-related proteins has been studied in a cohort at high risk for breast cancer including healthy females and those with benign breast disease. The results were evaluated versus certain risk factors of breast cancer. No significant difference in the incidence was established between cases of diffuse fibrocystic mastopathy and healthy subjects. Nor was there any relationship between positive serum incidence and age, number of abortions, age at first childbirth or postmenopause. However, this parameter appeared to be in direct correlation with the number of childbirths (beginning from 3). This index was significantly higher in women (aged 40 and more) with early menarche than in those with medium and late menarche (8 and 0%, respectively).

The presence of humoral antibodies specifically recognizing structural proteins of murine mammary tumor virus was studied in indirect immuno-enzymatic reaction, in 79 patients with suspected tumors of the breast. Diagnosis was verified after surgery by histological procedures. Said antibodies were detected in 13% of patients with benign tumors, lymphomas and mammary lymphosarcomas. However, in the breast cancer group including patients with T1-2N0M0 and T1N1M0, antibodies were identified in 85.7% of sera. It is suggested that patients with breast tumors who have antibodies to murine mammary tumor virus develop a specific nosological type of tumor which arises at reproductive age and is capable of high-rate growth and low-level metastatic spreading. Feasibility of application of said procedure for early detection of breast cancer is discussed.

The sera of women with benign and malignant mammary tumours were investigated for the presence of antibodies to structural proteins of retroviruses types C and D by indirect immunoenzyme assay (ELISA) and immunoblotting. Among 89 sera tested 5 reacted with the RD-114 protein, 2 with SSV, M-7, and bovine leukaemia virus proteins. None serum reacted with mouse mammary tumour virus proteins. On the basis of these results we conclude that the expression of antibodies to structural retrovirus proteins is not specific for mammary cancer.

In the blood serum of a proportion of breast cancer patients (29.4%) immune complexes specifically reacting with the immunoglobulins of the serum against MMTV structural proteins were detected using indirect enzyme-linked immunosorbent assay (ELISA). The presence of such complexes could decrease the titre of antibodies reactive with MMTV in the blood serum of breast cancer patients.

The immunoenzyme technique was used to identify sera reacting with mouse mammary tumor virus (MMTV) proteins in patients with mastopathy and healthy subjects. Their specificity to certain viral proteins was established by immunoblotting. Serum samples obtained from 14 subjects reacted mainly with p27 MMTV, while those taken from another two subjects--mainly with gp52 virus. Humoral antibodies against p27 MMTV were found in 3.3% of the entire study group whereas anti-gp52 antibodies--in 0.5%.

Circulating immune complexes were precipitated from breast cancer patients' sera using 2.5% polyethylene glycol. CIC isolated from 70 ml of sera from 15 patients were dissociated and immunoglobulin-containing fraction was prepared by chromatography on Sephadex G-200 column. The fraction contained IgG specific for MuMTV structural proteins, as revealed by ELISA. CIC preparations from 22 sera of breast cancer patients were digested with pepsin; Fab' fragment preparations were also analysed by ELISA, only one of them was MuMTV-specific. IgG and Fab' fragments isolated from CIC reacted specifically with MuMTV proteins, the reaction was not blocked by virus-free murine milk or other retroviruses (Ra-MuLV and MPMV).