Hematoporphyrin monomethyl ether (HMME) is a novel and promising porphyrin-related photosensitizer for
photodynamic therapy (PDT). We use the human breast cancer MCF-7 cells to investigate the photodamage effect of
HMME and reactive oxygen species (ROS) generation in HMME-PDT. Methods: The growth rates of MCF-7 cells at 24h
after irradiation by 532nm laser with HMME of 5~20μg/ml and light dose of 0.3~4.8J/cm<sup>2</sup> were determined by CCK-8
assays. Hoechst33342 staining was used to investigate the morphological change of the tumor cell. Flow cytometry
combined with dual Annexin V/PI staining was used to identify the death mode of the cells following PDT. The changes of
ROS labeled by DCFH-DA were observed by Laser Scanning Confocal Microscopy (LSCM). Our results show that
HMME-based PDT induced significant cell death, and the photocytotoxity to MCF-7 cells is dose-dependent at the range
of HMME concentration 5~20μg/ml and the light dose 0.3~4.8J/cm<sup>2</sup>. The nucleolus underwent apoptosis and/or necrosis
observed by LSCM with Hoechst33342 staining. The necrosis and apoptosis rate were 16.0% and 12.4% respectively by
FCM, showing the number of necrosic cells was more than that of apoptosis. There was an intense increase of fluorescence
intensity standing for ROS generation within 30min post-PDT, and the peak was at about 10min after PDT. Our results
suggest that HMME-PDT could inhibit the proliferation of MCF-7 cells remarkably. Because the MCF-7 cells lack
procaspase-3, the apoptosis rate is lower. ROS played an important role in the photodamage with HMME.
<b>Objective </b>To study the effects of HMME-based photodynamic therapy on proliferation and apoptosis of rabbit
vascular smooth muscle cells(VSMCs). <b>Method</b> The cytotoxic effect of HMME-PDT on rabbit vascular smooth
muscle cells was studied by means of Trypan Blue assay, HMME at 10&mgr;g/ml concentration and the light dose at 2.4~4.8
J/cm<sup>2</sup> were selected in the studies. The morphological character 24h post-PDT was investigated by HE Staining.
Annexin V and propidium iodide (PI) binding assays were performed to analyze the characteristics of cell death after
HMME-PDT. Furthermore, The intracellular distributions of the HMME were measured by the confocal laser scanning
microscope. <b>Result</b> It was showed the photocytotoxity to VSMC cells was dose related by Trypan Blue assay.
Histology observing suggests HMME-PDT could induce cell death through apoptosis or necrosis, and the apoptosic rate
was up to 50.5% by AnnexinV /PI assay. Moreover, the fluorescence images of HMME intracellular localization
demonstrated that the HMME diffused into the mitochondria. <b>Conclusion</b> HMME-PDT could significantly inhibite
VSMC proliferation and induce apoptosis.
In order to develop a novel diagnostic technique, as an adjunct modality to SDT, that uses the gallium-porphyrin derivative ATX-70 as a sonosensitiser mediated by a chemiluminescent probe to produce sonochemiluminescence (SCL) for imaging and localization of cancer within tissue in vivo. The fluoresceinyl Cyprodina luminescent analogue (FCLA) was used as an optical reporter for singlet oxygen generated from the sonosensitisation reaction of ATX-70 in the model solutions and in the in vivo nude mice bearing mammary cancer. The sonosensitized chemiluminescence from the reaction of FCLA with <sup>1</sup>O<sub>2</sub> was detected by a highly sensitive light-detector. The effect of FCLA with different doses on cell viability was also assessed with MTT assay. The results showed with the FCLA as the reporter, there is clear evidence that the aqueous solution of ATX-70 exposed to ultrasound forms <sup>1</sup>O<sub>2</sub> in the system. In the in vivo experiments, the tumor-bearing mice are imaged with a great contrast during sonosensitization of ATX-70 mixed with FCLA as the SCL probe. No significant cytotoxity was detected at the different FCLA doses. The results indicated that a novel cancer imaging method, named as the sonodynamic diagnosis (SDD), can be established by the sonodynamic action with the assistance of SCL probe. Therefore, this technique could have potential applications in the clinical diagnosis of cancer diseases at an early stage, and can be used to assess the treatment efficacy during the sonodynamic therapy of cancers.
We report the effect of laser wavelengths and HpD on diffuse reflectance of tumor surface in mice. Three kinds of lasers of six different wavelengths and hemetoporphyrin derivative as photosensitizer were used in the experiment. Tumor- bearing mice were divided into two groups. The mice of one group were given an i.p. injection of HpD 10 mg/kg. 24 hours later, the laser diffuse reflectance of tumor surface of the mice of two groups were measured by a single integrating sphere system with laser in six wavelengths. The results of measurement showed that significant difference of diffuse reflectance on tumor surface between the visible laser light and infrared laser light were observed. There was no significant difference in diffuse reflectance on tumor surface with and without i.p. injection of HpD. So it is unnecessary to consider the effect of HpD when calculating the actual laser dose irradiated into the tumor. The diffuse reflectance of tumor surface reaches its maximum at 1060nm wavelength, as twice as at 514.5 nm wavelength. It is hence concluded that diffuse reflectance should be taken into consideration when calculating the actual laser density for irradiation on tumors.
The present paper reports the effect of hyperthermia (HT) induced by Nd:YAG laser and photodynamic therapy (PDT) by AR<SUP>+</SUP> laser radiation in combination on the transplanted sarcoma 180 in CM mice. Tumor-bearing mice were divided into four groups: A) control group, B) HT group, C) PDT group and D) PDT followed by HT group. HT was induced by Nd:YAG laser radiation and the temperature at tumor edge was control at 43 degrees C for 30 minutes. Tumor-bearing mice of group C and D were given an i.p. injection of HpD 24 hours prior to AR<SUP>+</SUP> laser radiation. The experiments show significant increases in inhibition rates against the S-180 in CM mice by the HT and PDT combination, compared to those by either HT or PDT alone. With that of Group D being the lowest, the DNA contents of tumor cells in the four groups are of statistical significance too. These results suggest the combination of HT induced by Nd:YAG and PDT by Ar<SUP>+</SUP> laser radiation may become a new method of tumor treatment.