The study aimed at immunocytochemical evaluation of the cellular expression of two cytokines, IL-2 and IL-12 in lung carcinoids (n = 10), following the earlier demonstration of two markers of endocrine tumours (chromogranin A and NSE — neuron-specific enolase). In the immunocytochemical studies the classical avidin-biotinylated peroxidase (ABC) technique was used. Results of the tests were semiquantitatively appraised employing the IRS scale. In 9/10 cases intense reaction (score: 6–12 points) was noted for both lung neuroendocrine markers. In all cases of carcinoma co-expression of IL-2 and IL-12 was demonstrated in cells of the tumours. The cytokines showed a cytoplasmic localisation of mean (score: 3–4 points) or high (score: 6–12 points) intensity of reaction. Our studies point to a possible role of the two cytokines in the proliferation of lung neuroendocrine carcinomas but more detailed analysis is required on a broader material.
We investigated the feasibility of a novel therapeutic approach to treat neoplastic diseases in mice. This novel strategy consists in delivering a protein (angiostatin) with strong antiangiogenic properties, followed by administration of the interleukin 12 gene that is strongly immunomodulatory and has also some antiangiogenic effects. When angiostatin-mediated antiangiogenic therapy was used in combination with intratumor delivery of the IL-12 gene (a strategy much safer than IL-12 protein administration), this produced a synergistic therapeutic effect.
We investigated suppression of murine B16(F10) melanoma tumor growth following a therapy which involved concomitant administration of cyclophosphamide and plasmid DNA bearing interleukin-12 gene. Since both therapeutic factors display antiangiogenic capabilities, we assumed that their use in blocking the formation of new blood vessels would result in augmented inhibition of tumor growth. This combined therapy regimen indeed resulted in a considerable suppression of tumor growth. We observed a statistically significant extension of treated animals' lifespan. Interestingly, the therapeutic effect was also obtained using a plasmid without an interleukin gene insert. This observation suggests that plasmid DNA, which has been widely applied for treating neoplastic tumors, contains element(s) that elicit immune response in mice.