Local interleukin-2 and interleukin-12 therapy of bovine ocular squamous cell carcinomas

Mycobacterial Cell Wall Stimulant in the Treatment of Squamous Cell Carcinoma: A Case Series Regarding Treatment in Equine, Bovine and Caprine Patients

Squamous cell carcinoma (SCC) is a common dermatological neoplasia found in large animal species. Treatment options, such as surgery and cryotherapy may be difficult or not feasible. Alternative therapies, such as immunomodulating drugs, can potentially be used for companion large animals. The hypothesis of the following retrospective study is: following multiple intravenous and intralesional injections of a mycobacterial cell wall stimulant (MCW) regression of SCC in equine, bovine and caprine patients will be observed. In this observational-retrospective case series, patients included are 2 bovine, 2 caprine and 3 equine patients. The medical records at two different teaching veterinary hospitals were searched for cases with a positive histopathological diagnosis of squamous cell carcinoma that were subsequently treated with MCW, as either the sole therapy, or in conjunction with other therapies. Seven cases were included in this retrospective study. The median duration of therapy was 56.5 days, with 3 of the 7 patients being euthanized. Significant complications were seen in 3/7 patients. Repeated injections of a MCW may lead to reduction in lesion size of SCC in some cases, but long-term resolution is unlikely and the risk of significant complications is high; due to limited sample size and the variety in species, it is difficult to conclude if MCW is an effective therapy for SCC.

Immunohistochemical Studies of Cytokeratins and Differentiation Markers in Bovine Ocular Squamous Cell Carcinoma

Bovine Ocular Squamous Cell Carcinoma is considered the most common bovine tumour, causing significant economic losses, mainly by abattoir condemnations. To obtain a better insight into the genesis and neoplastic transformation, 19 samples collected at slaughter from Holstein Friesian cattle and diagnosed as Ocular Squamous Cell Carcinoma were studied. Tumours were histologically classified into three categories: poorly (26.3%), moderately (26.3%), and well differentiated (47.4%). Expression of keratins (MNF116 and LP34) and of cornified envelope precursors (involucrin and profilaggrin) was studied. Expression of MNF116 was observed in all carcinomas. LP34 immunostaining was seen in all but three carcinomas, one from each degree. Involucrin immunoreaction was observed in all but one poorly differentiated carcinoma. Profilaggrin was present in only two moderately differentiated carcinomas, in all but one well differentiated, and in all but one poorly differentiated. MNF116 is a useful marker to confirm the epithelial origin of the tumour and stain most neoplastic cells in these tumours. The expression of involucrin and LP34 demonstrates that, in all tumours, cells have reached the final program of differentiation, regardless of the grade. The expression of profilaggrin could indicate molecular changes during malignant transformation but their expression does not seem to be of diagnostic value.

Bovine ocular squamous cell carcinoma

Ocular squamous cell carcinoma (OSCC) in animals is a primary neoplasm of epithelial origin. OSCC or "cancer eye" is the most common malignant tumor affecting cattle in North America and is responsible for significant economic losses. In the United States, the prevalence of OSCC varies geographically and is higher in the southwestern region and in lower latitudes with higher levels of sunlight. Control of this disease would be of considerable significance to the economics and profitability of the beef and dairy cattle industries. This article reviews the characteristics of the most commonly affected animals, the factors that are believed to contribute to the development of OSCC, and the treatment options that have been proposed.

Local therapy of cancer with free IL-2

This is a position paper about the therapeutic effects of locally applied free IL-2 in the treatment of cancer. Local therapy: IL-2 therapy of cancer was originally introduced as a systemic therapy. This therapy led to about 20% objective responses. Systemic therapy however was very toxic due to the vascular leakage syndrome. Nevertheless, this treatment was a break-through in cancer immunotherapy and stimulated some interesting questions: Supposing that the mechanism of IL-2 treatment is both proliferation and tumoricidal activity of the tumor infiltrating cells, then locally applied IL-2 should result in a much higher local IL-2 concentration than systemic IL-2 application. Consequently a greater beneficial effect could be expected after local IL-2 application (peritumoral = juxtatumoral, intratumoral, intra-arterial, intracavitary, or intratracheal = inhalation). Free IL-2: Many groups have tried to prepare a more effective IL-2 formulation than free IL-2. Examples are slow release systems, insertion of the IL-2 gene into a tumor cell causing prolonged IL-2 release. However, logistically free IL-2 is much easier to apply; hence we concentrated in this review and in most of our experiments on the use of free IL-2. Local therapy with free IL-2 may be effective against transplanted tumors in experimental animals, and against various spontaneous carcinomas, sarcomas, and melanoma in veterinary and human cancer patients. It may induce rejection of very large, metastasized tumor loads, for instance advanced clinical tumors. The effects of even a single IL-2 application may be impressive. Not each tumor or tumor type is sensitive to local IL-2 application. For instance transplanted EL4 lymphoma or TLX9 lymphoma were not sensitive in our hands. Also the extent of sensitivity differs: In Bovine Ocular Squamous Cell Carcinoma (BOSCC) often a complete regression is obtained, whereas with the Bovine Vulval Papilloma and Carcinoma Complex (BVPCC) mainly stable disease is attained. Analysis of the results of local IL-2 therapy in 288 cases of cancer in human patients shows that there were 27% Complete Regressions (CR), 23% Partial Regressions (PR), 18% Stable Disease (SD), and 32% Progressive Disease (PD). In all tumors analyzed, local IL-2 therapy was more effective than systemic IL-2 treatment. Intratumoral IL-2 applications are more effective than peritumoral application or application at a distant site. Tumor regression induced by intratumoral IL-2 application may be a fast process (requiring about a week) in the case of a highly vascular tumor since IL-2 induces vascular leakage/edema and consequently massive tumor necrosis. The latter then stimulates an immune response. In less vascular tumors or less vascular tumor sites, regression may require 9-20 months; this regression is mainly caused by a cytotoxic leukocyte reaction. Hence the disadvantageous vascular leakage syndrome complicating systemic treatment is however advantageous in local treatment, since local edema may initiate tumor necrosis. Thus the therapeutic effect of local IL-2 treatment is not primarily based on tumor immunity, but tumor immunity seems to be useful as a secondary component of the IL-2 induced local processes. If local IL-2 is combined with surgery, radiotherapy or local chemotherapy the therapeutic effect is usually greater than with either therapy alone. Hence local free IL-2 application can be recommended as an addition to standard treatment protocols. Local treatment with free IL-2 is straightforward and can readily be applied even during surgical interventions. Local IL-2 treatment is usually without serious side effects and besides minor complaints it is generally well supported. Only small quantities of IL-2 are required. Hence the therapy is relatively cheap. A single IL-2 application of 4.5 million U IL-2 costs about 70 Euros. Thus combined local treatment may offer an alternative in those circumstances when more expensive forms of treatment are not available, for instance in resource poor countries.