Polyclonal Antibodies against a Structure Mimicking the Covalent Linkage Unit between Picornavirus RNA and VPg: An Immunochemical Study

We propose that therapy of patients with anticancer drugs that poison DNA topoisomerases induces formation of covalent complexes of cellular RNAs and DNA topoisomerases. The appearance of these complexes can be detected with antibodies against a synthetic hapten mimicking the covalent linkage unit Tyr-pU(p) of picornavirus RNA and VPg. We synthesized hapten [N(Ac),CO(NH2)]Tyr-(5 P --> O)Up-O-(CH2)6NH2, conjugated it with BSA, and immunized rabbits with the antigen obtained. The raised polyclonal antibodies were purified by successive affinity chromatography on BSA-Sepharose and hapten-Sepharose columns. Target antibodies recognized hapten and encephalomyocarditis virus RNA-VPg complex specifically as found using the dot-immunogold method. We believe that these antibodies might be useful to study mechanism of picorna and similar virus RNA synthesis. The discovery and qualitative determination of the cellular RNA-DNA topoisomerases covalent complexes with these antibodies might be useful to monitor therapy efficacy by drugs "freezing" dead-end complexes of DNA topoisomerases and nucleic acids and to understand the mechanism of DNA topoisomerase poisoning in situ.

Desialylation Decreases the Resistance of Apo B-Containing Lipoproteins to Aggregation and Increases Their Atherogenic Potential

Subfractions of apo B-containing lipoproteins (VLDL and intermediate-density lipoproteins) with reduced content of sialic acid were found in human blood. These lipoproteins are characterized by high capacity to spontaneous association (aggregation) and stimulated accumulation of cholesterol in smooth muscle cells of human aortic intima. In vitro treatment of apo B-containing lipoproteins with alpha-2,6-sialidase and alpha-2,3-sialidase stimulated aggregation and increased the ability of these particles to potentiate cholesterol accumulation in smooth muscle cells of the intact human aortic intima. Probably, desialylation of various apo B-containing lipoproteins can occur in the blood; this process decreases their resistance to aggregation, and increases the ability of these particles to stimulate accumulation of cholesterol in human aortic intima cells, i.e. increases their atherogenic potential.

[Investigation of the drug "Mamoclam" for the treatment of patients with fibroadenomatosis of the breast]

The clinical trial of a new drug "mamoclam" was carried out in patients with benign breast disease. The drug contains omega-3 polyunsaturated fatty acids, iodine and chlorophyll derivatives and is produced from the brown sea alga laminaria. The study involved 33 patients (mean age 42.5 +/- 1.1 yrs). Two tablets were administered thrice a day for three months. Examination included clinical evaluation of symptoms of mastopathy and dysalgomenorrhea, breast sonography and mammography. Therapeutic response presented as reduced mastalgia, premenopausal syndrome, dysmenorrhea and algomenorrhea, breast cyst regression as well as attenuated pain associated with benign breast disease and palpation. Positive response was reported in 94%. The drug should be recommended for benign breast disease treatment.

[Study of an antioxidant dietary supplement "Karinat" in patients with benign breast disease]

A randomized double blind placebo-controlled trial of efficiency of a dietary supplement "Karinat" in patients with benign breast disease was carried out. Karinat contains beta-carotene 2.5 mg, alpha-tocopherol 5 mg, ascorbic acid 30 mg and garlic powder 150 mg per one tablet. Out of 66 patients, 33 patients were given karinat, 33 were given placebo. The patients reccived a tablet of karinal or placebo twice a day during 6 months. Examinations of the patients included clinical estimation of symptoms of mastopathy and dysalgomenorrhea, breast sonography and mammography. It was found that karinat reduced the severity of mastalgia, premenstrual syndrome, dysmenorrhea and algomenorrhea and caused regression of palpable symptoms of the breast fibromatosis. On the whole karinat had positive action in 75.8% that was significantly greater by 45.5% as compared with placebo. Karinat may be useful for the treatment of patients with benign breast disease.

[Results of a prospective randomized investigation [Russia (St.Petersburg)/WHO] to evaluate the significance of self-examination for the early detection of breast cancer]

Indications for puncture or excision biopsy were significantly higher in the study group (7.5%) as compared with control (3.5%) (p < 0.01) in a randomized prospective controlled trial of a comprehensive breast cancer screening (123,748) carried out in the framework of a self-examination education program. In the self-examination group, detection rates were higher both for benign (1.1%) and malignant (0.85%) tumors than in control (0.5% and 0.69%, respectively) (p < 0.05). Early stage (T1NOMO, Tis) distribution difference in the study group and controls was insignificant--23 and 17.6%, respectively. Compliance with the program requirements including monthly or bimonthly self-examination was followed by higher 15-year survival rates (53.2%) in 70-75% as compared with controls(45.8%) (p = 0.05105): yet it did not affect mortality.

[Comparative characteristics of hormonal status in patients with receptor-negative cancers of the breast and of the endometrium]

2,429 breast cancer patients and 478 patients with endometrial carcinoma were examined. It was suggested that the absence of estrogen receptors (ER) and/or progesterone receptors (PR) should be accounted for by peculiar endocrine features (including those of reproductive function) of the patients' medical history and/or hormonal metabolic status (body weight, estrogenemia, insulinemia, etc.) at clinical detection of tumor. The differences between breast and endometrial cancer in receptor-negative (R-) incidence were related to age (decade of lifespan) and menstrual cycle. Indices describing hormone-metabolic status were used for identification of receptor-negative or receptor-positive status of tumor (reliability of 65-70% for breast cancer and 75-80%--endometrial carcinoma) when it was not feasible under laboratory conditions.

Tissue transglutaminase expression in breast carcinomas

Tissue transglutaminase (tTG) is known to participate in multiple cellular processes, including apoptosis, cellular adhesiveness etc. Alterations of tTG expression could contribute to the development of several categories of diseases, including AIDS, cancer etc. The aim of the study was to test the pattern and relevance of tTG expression in a subset of breast carcinomas. RT-PCR has detected tTG-specific RNA message in 11 out of 25 (44%) breast cancer samples. tTG message was detected in 6/8 (75%) breast carcinomas with high apoptotic index, but only in 5/17 (29%) with the low one (p = 0.03). Immunohistochemical analysis revealed that only 15% of breast carcinomas displayed tTG protein in tumor cells, while the staining of the stromal components occurred in approximately one-half of the tumours tested. Surprisingly, there was no significant association between tTG RNA expression and protein positivity. Moreover, there was no evident relationships between tTG immunostaining and apoptotic index or clinical parameters of breast neoplasms. There are at least 2 alternative explanations for the poor concordance between RNA and protein data. It is likely that the sensitivity of immunohistochemistry is not sufficient to detect functionally relevant tTG enzyme in all breast cancer sections. Otherwise, tTG RNA expression does not always lead to accumulation of its product in the tumor cells, but reflects the transcriptional activation of other pro-apoptotic genes due to common triggering mechanisms.

[Adjuvant chemotherapy with anthracyclines in comparison with the standard combination of CMF in breast cancer with high risk of relapse]

The effectiveness of adjuvant therapy with adriablastin and doxorubicin for breast cancer has been compared to that of standard CMF. During 1985-1990, the study included 349 patients with T1-2N2M0 and T3N0-2M0 tumors; mean age--46 yrs; mean follow-up--96.7 months. Overall survival rate in the doxorubicin group was 73%, CMF--62%; relapse-free survival--62.1 and 55%, respectively. The absolute difference in overall survival rates (11%) proved barely significant (p = 0.056). However, the difference in overall survival (p < 0.05) after anthracyclines and CMF in patients with tumors T1-2N2M0 and T3N1M0 was significant and in favor of the former. As far as frequency and degree of side-effects is concerned, their patterns were practically identical in both groups, except for the significantly higher frequency of cardiotoxity and complete alopecia in doxorubicin therapy. Cardiotoxic complication rate was significantly reduced from 13.8 to 3.9% by cardioxane treatment.

[Interim results of a prospective randomized study of self-examination for early detection of breast cancer (Russia/St.Petersburg/WHO)]

Training in breast self-examination (BSE) technique involved 57,712 women, aged 40-64, at 14 out of randomly selected out-patient hospitals in St. Petersburg (1985-1989). Another 64,759 women selected at another 14 out-patient hospitals were in control. All patients with detected tumor pathology of the breast were biopsied and treated at the Institute's Clinic. The study focused on breast cancer incidence, survival and mortality. More women in the BSE group sought medical advice for suspected pathology (4,300) than those in control (2,438; p < 0.05). There were 493 cases of breast cancer in the BSE group with 157 fatalities, 446 cases of breast cancer with 167 fatalities in the control group. There was no significant difference in tumor stage. Nine-year survival (after Kaplan-Meyer) from the time of tumor detection was 65% in the study group and 55% in control (log rank 0.774; p > 0.05). There has been no significant difference in death rates in both groups for the past ten years. The study is to continue until the year 2001.

[The effectiveness of adjuvant chemotherapy with anthracyclines (adriablastin, doxorubicin) for stage-IIb-IIIa breast cancer]

The effectiveness of adjuvant treatment with anthracyclins (adriablastin, doxorubicin) and standard CMF regimens for breast tumors has been compared. The study included 349 patients with stage IIB-IIIA tumors (T1-2N2M0, T3N0-2M0) (mean age-46 years) during 1985-1990 follow-up-60.38 months. In the doxorubicin group, overall 5-year survival was 73 +/- 8%, in the CMF group-62 +/- 8%. Recurrence-free 5-year survival was 62 +/- 8 and 55 +/- 8%, respectively. The differences are not significant. A stage-related analysis established a significant difference in overall survival in patients with T1-2N2M0 tumors (c-sqare 9.92, p < 0.01). However, due to a small number of cases, the phenomenon requires further study. Although adriablastin treatment involved a significantly higher frequency of carciotoxic symptoms, complete alopecia and dyspeptic complication, a systemic administration of cardioxan and effective antiemetic drugs was lacking.