Induction of Immune Mediators in Glioma and Prostate Cancer Cells by Non-Lethal Photodynamic Therapy

BACKGROUND: Photodynamic therapy (PDT) uses the combination of photosensitizing drugs and harmless light to cause selective damage to tumor cells. PDT is therefore an option for focal therapy of localized disease or for otherwise unresectable tumors. In addition, there is increasing evidence that PDT can induce systemic anti-tumor immunity, supporting control of tumor cells, which were not eliminated by the primary treatment. However, the effect of non-lethal PDT on the behavior and malignant potential of tumor cells surviving PDT is molecularly not well defined. METHODOLOGY/PRINCIPAL FINDINGS: Here we have evaluated changes in the transcriptome of human glioblastoma (U87, U373) and human (PC-3, DU145) and murine prostate cancer cells (TRAMP-C1, TRAMP-C2) after non-lethal PDT in vitro and in vivo using oligonucleotide microarray analyses. We found that the overall response was similar between the different cell lines and photosensitizers both in vitro and in vivo. The most prominently upregulated genes encoded proteins that belong to pathways activated by cellular stress or are involved in cell cycle arrest. This response was similar to the rescue response of tumor cells following high-dose PDT. In contrast, tumor cells dealing with non-lethal PDT were found to significantly upregulate a number of immune genes, which included the chemokine genes CXCL2, CXCL3 and IL8/CXCL8 as well as the genes for IL6 and its receptor IL6R, which can stimulate proinflammatory reactions, while IL6 and IL6R can also enhance tumor growth. CONCLUSIONS: Our results indicate that PDT can support anti-tumor immune responses and is, therefore, a rational therapy even if tumor cells cannot be completely eliminated by primary phototoxic mechanisms alone. However, non-lethal PDT can also stimulate tumor growth-promoting autocrine loops, as seen by the upregulation of IL6 and its receptor. Thus the efficacy of PDT to treat tumors may be improved by controlling unwanted and potentially deleterious growth-stimulatory pathways

ICAR: endoscopic skull‐base surgery

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Cerebrospinal fluid leakage as complication of treatment with cabergoline for macroprolactinomas.

Item does not contain fulltextTreatment of patients with prolactinomas consists primarily of dopamine agonists (DA). Cerebrospinal fluid (CSF) leakage has sporadically been reported in patients with macroprolactinomas treated with short-acting DA such as bromocriptine. Little is known on the incidence of this complication in patients treated with the long-acting D2 specific DA cabergoline. We report three patients with CSF leakage shortly after initiation of cabergoline treatment for macroprolactinoma. All three patients responded rapidly to cabergoline (CAB) by shrinkage of the tumor and release of the optic chiasm compression. The CSF leakage occurred within 10 days after initiation of treatment. CAB treatment was not discontinued. In one patient the CSF leakage ceased spontaneously, with no additional therapy. The second patient had a surgical repair of the CSF fistula, permitting cabergoline to be continued without a recurrence of the CSF leakage. The third patient refused surgical repair of the sellar defect. In this patient the cabergoline dosage was temporarily decreased with no effect on the CSF leakage. Four years later, the CSF leakage is unchanged in this patient, whilst no other complications occurred during the follow-up. No infectious complications occurred in these three patients. In conclusion, patients with large, invasive macroprolactinomas are at risk of CSF leakage during medical treatment with CAB. It is advisable to warn these patients for occurrence of this complication and to monitor them closely especially during the first months of treatment