PATHOLOGICAL STUDIES ON BCG AND HYPERICIN MEDIATED PHOTODYNAMIC THERAPY (PDT) IN TUMOR TREATMENT IN MICE

Abstract

The purpose of the current study is to evaluate the effectiveness of Hypericin Photodynamic therapy (PDT) alone or associated with BCG immunization as an oncotherapy in Swiss mice. For this purpose, 90 mature male swiss mice were chosen and equally divided into 5 comparable groups. The first, was a negative control group, the second was hypericin contol group and the third was tumor control group. The forth and fifth groups were the treated groups with Hypericin-PDT and BCG/ Hypericin – PDT, respectively. They were subjected to the treating regimen as follows: a dose of 5 mg/kg body weight of an aqueous ethanolic Hypericin solution was injected by both intra-peritoneal (i.p.) and intratumoral (i.t.) injections, followed 2 hours later by exposure to non-coherent light (590 nm) for 5 minutes in each session. Mice received 5 sessions / week for 6 weeks. Both treatments resulted in pronounced degeneration and necrosis of the neoplastic cells with replacement of tumor masses by fibrous connective tissue. The curative rate was enhanced when Hypericin-PDT was accompanied by BCG as an immuno-stimulating agent. From the pathological pictures, it can be concluded that Hypericin-PDT is an effective treatment for superficial neoplasms. BCG administration, as a non-specific immuno-stimulant, enhances the therapeutic effect of Hypericin -PDT.