Cellular events accompanying regression of skin recurrences of breast carcinomas treated with intralesional injections of natural interferons alpha and gamma.

Cutaneous recurrences of breast carcinomas were treated with 10 i.l. injections of nIFNs alpha and gamma delivered in combination (7 lesions) or singly (11 with nIFN-alpha, one with nIFN-gamma). Histologically confirmed complete regressions occurred in 5 of 7 lesions treated with nIFN-alpha/nIFN-gamma and in 5 of 11 recurrences injected with nIFN-alpha alone. In all cases specimens were obtained before and after therapy. In addition, in some cases (4 treated with nIFN-alpha/nIFN-gamma, 2 with nIFN-alpha, one with nIFN-gamma) multiple recurrences were injected simultaneously and were excised 24 h after 1, 3, and 10 injections and 21 days after completion of therapy. The main findings observed in the treated lesions undergoing complete and partial regressions included: (a) inhibition of mitotic activity and up-regulation of antigenic expression (mammary epithelial membrane antigen, intercellular adhesion molecule 1, HLA-DR) by the carcinoma cells; (b) activation of macrophages and dendrocytes with marked expression of HLA-DR and HLA-A,B,C; (c) infiltration of the dermis and tumors by activated T-lymphocytes (CD3+, CD4+, CD8+); (d) questionable participation by B-lymphocytes and natural killer cells; (e) activation of endothelium with enhancement of antigenic expression (intercellular adhesion molecule 1, HLA-DR), procoagulant activity, and vascular permeability. The responses elicited by nIFN-alpha/nIFN-gamma were greater than those caused by either IFN used alone. It appears that in these patients the IFNs exerted an antiproliferative action and potentiated a cell-mediated immunological response liminally present in the neoplastic tissues prior to therapy.

Detection of estrophilin in frozen sections of breast cancers using an estrogen receptor immunocytochemical assay.

Estrogen receptor (ER) was detected in frozen sections of 36 breast carcinomas using an antiestrophilin monoclonal antibody according to an immunocytochemical technique elaborated and made available by Abbott Laboratories in the form of a kit (ER-immunocytochemical assay monoclonal). Immunostaining was confined to the nuclei of the carcinoma cells. In all positive specimens, nuclei with different staining intensities were present in addition to a variable number of unstained nuclei, presumably because of functional heterogeneity. Of the 36 carcinomas, 27 displayed positive immunostaining, 4 had no staining, and in 5 the staining was borderline. All specimens were assayed for ER content by the dextran-coated charcoal (DCC) technique. When the DCC values were compared with the results of immunostaining it was found that 4 tumors were negative and 27 were positive by both techniques, whereas of 5 cases with borderline staining 3 were negative by DCC and 2 had low DCC values. These correlations proved to be highly significant (P much less than 0.001). The number of stained nuclei (extent of staining) related to the DCC status in a significant manner (P less than 0.01), whereas the intensity of staining did not (P greater than 0.10). These results indicate that immunocytochemical visualization of ER using Abbott's "ER-Immunocytochemical Assay Monoclonal" kit is an easy, reproducible, and reliable technique.

Regression of human breast cancer xenografts in response to intralesional treatment with interferons alpha and gamma potentiated by tumor necrosis factor.

The potentiating effects of human recombinant tumor necrosis factor-alpha (rTNF-alpha) on the antitumor actions of recombinant interferon-gamma (rIFN-gamma) and of natural interferons alpha and gamma combined (nIFN-alpha/nIFN-gamma) were studied on human breast cancer xenografts growing bilaterally in nude mice. The cytokines were injected singly or in combination in one of the two tumors of each mouse to study local effects while the opposite tumor was left undisturbed to evaluate systemic effects. The tumors received 20 intralesional injections (four cycles of 5 daily injections each). In injected tumors the best results were obtained with nIFN-alpha/nIFN-gamma supplemented with rTNF-alpha. The responses were dose dependent, resulting in complete regression of 9 of 9 tumors with rTNF-alpha used at the dose of 5 micrograms per injection, of 6 of 8 tumors at the dose of 2.5 micrograms, and of 4 of 8 tumors at the dose of 0.5 microgram. Mostly mild to moderate partial responses were seen in the other groups. The systemic effects on the contralateral tumors were significantly less than the local effects on the corresponding tumors. Histologically, responding tumors showed reactive fibrosis and inflammatory cell infiltration. No vascular alterations were seen, presumably because of the immunodeficiency of nude mice. It was concluded that the potentiation of the antitumor actions of IFNs by rTNF-alpha was effective at the local but not at the systemic level.

Immunostaining of estrogen receptor in paraffin sections of breast carcinomas using monoclonal antibody D75P3 gamma: effects of fixation.

Immunostaining of estrogen receptor was carried out on paraffin sections of breast carcinomas using an anti-estrophilin monoclonal antibody (D75P3 gamma) and the avidin-biotin technique. The tumors were fixed in Bouin's solution or in formalin for varying periods of time at room temperature or at 4 degrees C. Best results were obtained following fixation in Bouin's at room temperature or in formalin at 4 degrees C. The staining was localized in the nuclei of carcinoma cells and was heterogeneous in intensity and extent. Prolonged fixation resulted in decreased immunoreactivity and in the appearance of nonspecific cytoplasmic and background staining. The estrogen receptor immunostaining on paraffin sections was found to be in concordance with that on frozen sections (Abbott ER-ICA) and with the steroid-binding assay (dextran-coated charcoal) in over 90% of the cases. This method is of easy and rapid execution and yields reliable and reproducible results.

Safety of repeat aprotinin administration for LVAD recipients undergoing cardiac transplantation.

BACKGROUND: Anecdotal reports of allergic and anaphylactic reactions after aprotinin therapy have raised concern that its repeat use may be associated with substantial morbidity. METHODS: To address this concern, we reviewed our experience with all patients who underwent implantation of a left ventricular assist device and subsequent cardiac transplantation with perioperative use of aprotinin. RESULTS: Twenty-three patients received full-dose aprotinin during left ventricular assist device implantation and subsequent cardiac transplantation. All patients tolerated primary exposure to aprotinin without complication. One episode of anaphylaxis after secondary exposure was treated with rapid institution of cardiopulmonary bypass. Although renal dysfunction was observed shortly after cardiac transplantation in 30.4% of patients, the effect was transient and occurred in the presence of cyclosporine. The one perioperative death after secondary exposure was unrelated to bleeding complications. No clinically evident thromboembolic events were documented. CONCLUSIONS: Primary and secondary exposure to aprotinin during operation with cardiopulmonary bypass is associated with limited intraoperative blood use, a low incidence of transient renal dysfunction and anaphylaxis, a rare need of reoperation for bleeding, and no clinical thromboembolic events.

Regression of skin recurrences of breast carcinomas treated with intralesional injections of natural interferons alpha and gamma.

Two groups of patients with disseminated breast carcinomas who had failed radiotherapy, chemotherapy, and hormonotherapy were treated with natural interferon alpha (nIFN-alpha) alone or in combination with nIFN-gamma delivered in cycles of 10-12 intralesional (i.l.) injections to recurrent and metastatic lesions. In group, I, 16 skin lesions in 12 patients received nIFN-alpha alone resulting in 7 complete regressions verified histologically (CR), 7 partial regressions (PR), and no regressions (NR) in 2. Group II included 4 patients in whom 7 cutaneous recurrences were treated with nIFN-alpha/nIFN-gamma (5 CR, 2 PR), 2 were injected with nIFN-alpha alone (1 CR, 1 PR), and 1 received nIFN-gamma alone (PR). Two additional patients in group II were given i.l. injections of nIFN-alpha/nIFN-gamma to lymph node metastases (1 CR, 1 PR). Clinical toxicity was experienced by 5 of 12 patients in group I and by all the patients in group II and was controlled in most instances by antipyretics. Systemic antitumor effects were not appreciable clinically. Nevertheless, noninjected lesions exposed only to systemic levels of IFNs, when studied immunohistochemically, displayed an immunological response similar to that of IFN-injected lesions, although less intense. Therefore, IFNs can be useful in controlling locoregional recurrences of breast cancer even in patients who are not responding to other forms of therapy. Furthermore, in addition to the local antitumor actions, they appear to be capable of eliciting systemic immunological effects.

Treatment of human breast cancer xenografts using natural interferons-alpha and -gamma injected singly or in combination.

Natural interferons (nIFNs) -alpha and -gamma were used to treat nude mice bearing bilateral xenografts of human breast cancer cells (MCF-7 and BT 20). The IFNs were administered singly or in combination by means of intralesional (i.l.) or intraperitoneal (i.p.) injections. In the animals treated intralesionally 1 of the 2 tumors was injected to study the local therapeutic effects, while the contralateral one was left undisturbed and used to assess systemic effects. Treatment of MCF-7 tumors with i.l. injections of nIFN-alpha and nIFN-gamma combined resulted in complete regression of the injected tumors in 8 of 20 mice treated for 2 weeks and in 10 of 10 mice of an additional group treated for 4 weeks. The corresponding contralateral tumors showed complete regression in 2 mice treated for 4 weeks and partial responses in the others. Incomplete responses were also observed when the IFNs were used singly or when they were delivered intraperitoneally. Similarly, in BT 20 xenografts the best results were obtained with i.l. injections of the 2 IFNs combined, but no complete regressions were achieved. These experiments provide further evidence for a synergistic interaction of nIFN-alpha and nIFN-gamma in vivo and indicate that the potentiated antitumoral activity is greater when these interferons are administered i.l.

Effects of intralesional injections of interferons-alpha on xenografts of human mammary carcinoma cells (BT20 and MCF-7).

The effects of intralesional injections of human natural and recombinant interferons-alpha (nIFN-alpha and rIFN-alpha A) were studied in nude mice bearing bilateral xenografts of human mammary carcinoma cells (BT 20, MCF-7). One tumor of each animal received intralesional injections, while the contralateral tumor was left undisturbed. Thus, the injected tumors were subjected to the local action of the IFNs whereas the opposite ones were exposed to the systemic effects of the IFNs seeping into the subcutaneous tissue following the intratumoral injection. When used singly these IFNs exerted an inhibitory effect on the growth of both injected and contralateral tumors, but failed to cause complete regression. Many of the cells of treated BT 20 xenografts showed significant morphological alterations (increased cell volume and nuclear pleomorphism) as compared to the untreated controls. Morphological alterations in MCF-7 tumors were difficult to assess because of the inherent pleomorphism of these cells. The immunoreactivity of BT 20 and MCF-7 tumors to monoclonal antibodies directed against milk fat globule proteins and against HLA antigens was not appreciably affected by treatment with these IFNs. This study confirms that intralesional injections of human IFNs-alpha partially inhibit the growth of human breast cancer xenografts, probably through a direct effect on the carcinoma cells. Under the present experimental conditions, the intralesional and the subcutaneous routes of administration appear to offer comparable antitumor effectiveness.

The use of natural interferon alpha conjugated to a monoclonal antibody anti mammary epithelial mucin (Mc5) for the treatment of human breast cancer xenografts.

An immunoconjugate composed of natural interferon alpha (nIFN alpha) bound in a noncleavable fashion to a monoclonal antibody (MoAb) recognizing a breast epithelial membrane mucin (Mc5) was used to to treat xenografts of a human mammary carcinoma cell line (MCF-7) growing in nude mice. The immunoconjugate (nIFN alpha/Mc5) was administered as 20 intralesional (i.l.) injections to 1 of 2 xenografts in each animal. It was found that nIFN alpha/Mc5 produced a significant enhancement of the growth inhibitory actions of nIFN alpha on the injected tumors. Further enhancement was obtained when nIFN gamma or nIFN gamma together with Mc5 (at a dose 10 times larger than that present in nIFN alpha/Mc5) were added to the immunoconjugate. Biodistribution experiments showed that the uptake of 125I-nIFN alpha/Mc5 by the tumors was greater and its elimination slower than for 125I-nIFN alpha alone or conjugated to irrelevant mouse IgG1. In addition, the immunoconjugate up-regulated the antigenic expression of a breast epithelial membrane mucin by the carcinoma cells, an up-regulation which was not significantly different from that produced by nIFN alpha alone. The contralateral noninjected tumors exposed to systemic levels of the immunoconjugate showed an enhancement of antitumor effects, but to a lesser extent than the injected tumors. These findings suggest that the enhancement of the growth inhibitory action of the immunoconjugate was related to the specific binding of Mc5 which targeted the IFN to the carcinoma cells and impeded its elimination. It is likely that the targeting was favored by the IFN-mediated up-regulation of antigenic expression by the carcinoma cells, thereby producing a cascade of interrelated effects. The results of this study point out the feasibility and potential usefulness of IFN treatment by means of immunoconjugates as well as the worth of pursuing and improving this form of therapy.

Conjugation of interferon alpha to a humanized monoclonal antibody (HuBrE-3vl) enhances the selective localization and antitumor effects of interferon in breast cancer xenografts.

Human mammary carcinoma xenografts (MCF-7) growing in nude mice were treated with natural interferon alpha (n-IFN-alpha) alone or conjugated to a humanized monoclonal antibody (MoAb) anti-breast mucin (HuBrE-3vl) or to irrelevant human IgG1kappa. The IFN and the conjugates were administered as 20 intra-lesional (i.l.) injections to 1 of 2 xenografts in each mouse, or i.p. The growth inhibitory effects of HuBrE-3vl/nIFN-alpha were significantly greater than those of nIFN-alpha used as a single agent or conjugated to HuIgG1kappa. These effects occurred locally in the tumors receiving i.l. injections and systemically, although to a slightly lesser extent, in the noninjected tumors of mice treated i.l. and in the xenografts of mice treated i.p. Biodistribution studies showed that the uptake of 125I-HuBrE-3vl/nIFN-alpha by the tumors 24 hours after i.l. or s.c. injection was greater than that of 125I-HuIgG1kappa/nIFN-alpha, 125I-nIFN-alpha alone, or by normal tissues, documenting a tumor targeting effect and favorable tumor:normal tissues (T:NT) ratios. The targeting effects and the resulting tumor growth inhibition were favored by the IFN-mediated up-regulation of the HuBrE-3vl reactive antigen, which was more prominent after 3 weeks of treatment with HuBrE-3vl/nIFN-alpha. These results were superior to those we obtained previously with nIFN-alpha conjugated to another MoAb of the same group (Mc5). These studies point out the potential usefulness of HuBrE-3vl/nIFN-alpha for the local and systemic treatment of breast cancer lesions by providing a means of delivering high doses of IFN to the tumors while minimizing the amount of IFN binding to normal tissues.