Therapeutic effect of the treatment for colorectal cancer with adenoviral vectors mediated estrogen receptor ß gene therapy combined with thermotherapy.

INTRODUCTION: Our preliminary study on repressing colorectal tumors by recombinant adenoviruses (Ads) delivering the human ERß gene (Ad-ERß) has achieved positive result. METHODS: In this study, hydrophobic fluorescent dyes ICG-Der-01 was entrapped into the N-succinyl-N'-octyl chitosan (SOC) micelles to form the near infrared absorbing dyes SOC-ICG-Der-01 and SOC-ICG-Der-01 mediated near infrared laser (SOC-ICG-Der-01/NIR) thermotherapy was combined with Ad-ERß gene therapy to regress colon cancer in vivo. RESULTS: Firstly, the antitumor efficacies of SOC-ICG-Der-01/NIR thermotherapy were investigated on S180 ascites tumor-bearing mice. Results indicated that, the average tumor volume of SOC-ICG-Der-01/NIR group was the smallest among the three treatment groups. Then, thermotherapy with SOC-ICG-Der-01/NIR combined with Ad-ERß gene therapy to treat HCT-116 colon cancer xenograft model was investigated. Further results demonstrated that, SOC-ICG-Der-01/NIR thermotherapy showed the significantly inhibitory efficiency compared with control group and Ad-ERß enhanced the therapeutic effect of SOC-ICG-Der-01/NIR. CONCLUSION: These findings demonstrated that combined administration of Ad-ERß with SOC-ICG-Der-01/NIR thermotherapy represents a promising colon cancer therapeutic strategy.

Gold nanorod mediated plasmonic photothermal therapy: a tool to enhance macromolecular delivery.

Plasmonic photothermal therapy (PPTT) with gold nanostructures has been used to generate significant heat within tumors to ablate vasculature. Here we report the use of gold nanorod (GNR) mediated PPTT to induce moderate hyperthermia as a tool to enhance the delivery of macromolecules. GNRs were injected intravenously in a mouse sarcoma (S-180) tumor model. After 24h Evans blue dye (EBD) was injected and the right tumor was radiated with a laser diode for 10 min. EBD content in the right and left tumors were extracted in formamide, measured spectrophotometrically and expressed as a thermal enhancement ratio (TER). Enhanced delivery of EBD was observed (up to 1.8-fold) when tumor temperatures reached 43°C or 46°C. No statistical difference was observed between tumors at these two temperatures, though significant hemorrhage was observed in tumors and surrounding areas receiving the higher thermal dose (46°C). These results indicate that tumor directed PPTT may be used to induce moderate hyperthermia and therefore selectively increase the delivery of macromolecules with therapeutic anticancer drugs.

Substance P and beta-endorphin mediate electro-acupuncture induced analgesia in mouse cancer pain model.

BACKGROUND: Opioid analgesics are generally used to combat the pain associated with cancerous conditions. These agents not only inhibit respiratory function and cause constipation, but also induce other significant side effects such as addiction and tolerance, all of which further contribute to a reduced quality of life for cancer patients. Thus, in the present study, the effects of electro-acupuncture treatment (EA) on mechanical allodynia were examined in a cancer pain mouse model. METHODS: In order to produce a neuropathic cancer pain model, S-180 sarcoma cells were inoculated around the sciatic nerve of left legs of Balb/c mice. Magnetic Resonance Imaging (MRI) scanning confirmed the mass of S-180 cancer cells embedded around the sciatic nerve. Mechanical allodynia was most consistently induced in the mouse sarcoma cell line S-180 (2 x 10(6)sarcoma cells)-treated group compared to all the other groups studied. EA stimulation (2 Hz) was administered daily to ST36 (Zusanli) of S-180 bearing mice for 30 min for 9 days after S-180 inoculation. RESULTS: EA treatment significantly prolonged paw withdrawal latency from 5 days after inoculation. It also shortened the cumulative lifting duration from 7 days after inoculation, compared to the tumor control. Also, the overexpression of pain peptide substance P in the dorsal horn of the spinal cord was significantly decreased in the EA-treated group compared to the tumor control on Day 9 post inoculation. Furthermore, EA treatment effectively increased the concentration of beta-endorphin in blood and brain samples of the mice to a greater extent than that of the tumor control as well as the normal group. The concentration of beta-endorphin for EA treatment group increased by 51.457% in the blood and 12.6% in the brain respectively, compared to the tumor control group. CONCLUSION: The findings of this study suggest that a S-180 cancer pain model is useful as a consistent and short time animal model. It also indicated that EA treatment could be used as an alternative therapeutic method for cancer pain due to a consequent decrease in substance P and increase in beta-endorphin levels.

The tumoricidal effect of sonodynamic therapy (SDT) on S-180 sarcoma in mice.

There are increasing data showing that sonodynamic therapy (SDT), which refers to a synergistic effect of drugs and ultrasound, is a promising new modality for cancer treatment. However, few clinical data on SDT have been published. One reason is the lack of suitable drugs for clinical SDT use. Recently a new sonosensitizing agent has been developed by SonneMed, LLC, referred to as SF1. In this study the effect of SDT with SF1 on S-180 sarcoma in mice was examined. The tumor bearing mice were allocated to the following groups: (1) sham-treatment (control, C); (2) ultrasound treatment (only ultrasound treatment, 1.2 mW/cm2 , without SF1, U); (3) SF1 treatment (SF1 20 mg/kg intraperitoneal [ip] without ultrasound treatment, S); and (4) SF1 + ultrasound treatment (SU). Following treatment, tumor volume was monitored. Tumor growth inhibition was seen only in group SU, and with increasing ultrasound intensity, the inhibitory effect was enhanced. Tumor growth inhibition was also visible even when covered by a barrier of bone. Pathological slices showed coagulated necrosis or metamorphic tissue with inflammatory reaction in the tumor taken from 2 to 36 hours after SDT. These data revealed that SDT with SF1 did inhibit growth of mouse S-180 sarcoma and the inhibitory effect was sound intensity dependent. SDT also induced some inflammation while it destroyed the tumor, indicative of a "vaccine" effect. SF1 shows great promise for clinical use in the future.

[Electrochemotherapy and its mechanism for sarcoma of KM mice].

In this paper are analyzed the effect of electrochemotherapy and its mechanism. The favorable parameter of electric pulses (EP) was studied in vitro using the S-180 cells exposed to various EP. After the tumor model was copied, the tumor-bearing mice were randomly divided into four groups: control, chemotherapy, electrotherapy, and electrochemotherapy. The tumor inhibitory ratio, the cure ratio and the level of oxygen free radicals (OFR) were determined. The inhibitory ratio and cure ratio of electrochemotherapy group were significantly higher than those in the chemotherapy, electrotherapy and control groups (P < 0.05). The injury of OFR was decreased while the immunological competence was increased. The mechanism of electrochemotherapy may be related with the enhancement of cell membranepermeability, the depression of drug resistance, the improvement of immunological competence, and so on.

Response of S 180 murine tumor to bleomycin in combination with radiation and hyperthermia using micronucleus assay: a multimodality approach for therapeutic augmentation.

Response of a transplantable tumor, S180, grown intradermally in inbred Balb/c mice, was assessed by using micronucleus assay after treating the solid tumors with bleomycin (BLM), radiation (RT) and hyperthermia (HT) vis-a-vis multimodality approach. The frequency of micronuclei (MN) though did not vary greatly during the one week of observation in untreated tumors, it significantly increased in the drug and RT groups at 24 hr post-treatment. However, MN frequency was non-significant in the HT group from the control. A drug dose dependent linear increase in the frequency of MN induction was evident in 10, 15 and 20 mg/kg body weight BLM alone treated groups. Combination of radiation with BLM or HT further increased the MN counts in the bimodality groups. But, MN induction at 24 hr post-treatment in the trimodality group (BLM + RT + HT) was non-significant from that of the bimodality treatments. However, the tumors treated with trimodality treatment presented severe tumor necrosis, indicating increased cell loss, and resulting in immediate tumor regression. In all the bi-modality groups MN counts though declined 3 or 5 days post-treatment, the values remained significantly higher than the control, on day 7 post-treatment. Micronucleus assay could be used as a predictive parameter for the assessment of post-irradiation tumor regression response. However, the tumor response assessment with MN assay alone may not be sufficient and the role of other parameters, such as apoptosis and necrosis, in immediate tumor regression, especially radiosensitive/thermosensitive tumors can not be ignored while taking multimodality approach into consideration for cancer therapy.

[Inhibitory effect of electrochemotherapy on S180 tumor growth and angiogenesis and the possible mechanism].

This study evaluated the effects of electric pulses combined with antitumor drugs on S180 tumor cells. It was found that the growth of S180 sarcoma was inhibited with a maximum inhibition ratio of 95.5% after the use of electric pulses in combination with the injection of bleomycin (BLM), and the blood vessels of tumor were obviously fewer than those of the untreated tumor in vivo. The mitochondria of S180 tumor cells were swollen after the use of electric pulses in combination with adriamycin. The results showed that electrochemotherapy has evident inhibitory effect on the growth of S180 sarcoma and the mechanism may involve the suppression of tumor angiogenesis and changes in the ultrastructures of tumor cells.

[Antitumor effects of electrothermal and electrochemical therapy on mice with sarcoma180].

OBJECTIVE: To explore the anti-tumor effects and the mechanism of a new treatment for Sarcoma180 in mice using both hyperthermia (H) and electrochemical therapy (ECT). METHODS: A group of mice with Sarcoma180 (1 cm in diameter) were divided randomly into four groups and given different treatments: Control, ECT alone, H alone and electrothermal & electrochemical therapy (ETECT). The volumes of the tumors were calculated everyday after treatment. The tumor tissues were examined morphologically at 0, 6, 24 and 72 hours after treatment. RESULTS: The tumors treated with ETECT were completely destroyed, and did not recur within a period of ten days by pathological examination. Results of this group were significantly different with the other groups (P<0.01). However, recurred tumors were found in 6 mice of H group and 5 mice of ECT group, respectively. CONCLUSIONS: Based on the results obtained, ETECT induced by ETECD (D-device) is an effective way to eliminate cancer. It is capable of completely destroying cancer cells in a short time. The rate of Sarcoma180 inhibition is 100%, and malignant cells can't recur. The research provided theoretical and experimental bases for the treatment of oral cancer by a new approach to treat oral cancer.

[Study of high-intensity electric pulse inhibited sarcoma for improving antitumor drug effect].

This article reports the experiment studies on treating the S-180 sarcomas of KM mice with high-intensity electric pulse and antitumor drug (cyclophosphamide). The results showed that the experimental group of electric field combined with drug has the best effect on tumor, compared with the control group. In addition, electric field can inhibit the formation of vas Capillaries and decrease the supply of nutrition for tumor cell. In conclusion, electric field has inhibited the growth of tumor.

Effects of moxa-cone moxibustion at Guanyuan on erythrocytic immunity and its regulative function in tumor-bearing mice.

In the sarcoma S180 ascitic mice, the effects of moxa-cone moxibustion at Guanyuan (CV 4) on erythrocytic immunity and its regulative function were investigated. The results indicated that moxibustion at Guanyuan (CV 4) could significantly increase the decreased erythrocytic C3b receptor rosette forming rate (RBC-C3bRR), lower the raised erythrocytic immunocomplex rosette forming rate (RBC-ICR, P < 0.05 or P < 0.01), increase the decreased activity of erythrocytic immuno-accelerative factor, and reduce the increased activity of erythrocytic immunosuppressive factor (P < 0.05) in the tumor-bearing mice. This suggests that moxibustion at Guanyuan (CV 4) can strengthen erythrocytic immunity and promote its regulative function.

Use of 5-FU plus hyperbaric oxygen for treating malignant tumors: evaluation of antitumor effect and measurement of 5-FU in individual organs.

PURPOSE: Hyperbaric oxygen (HBO) has been shown to increase tumor radiosensitivity. Several reports indicate that it also increases sensitivity to alkylating agents, but other reports suggest that it may speed angiogenesis and tumor growth. To throw light on these questions, we investigated the effects of HBO and 5-fluorouracil (5-FU), individually and in combination, on Sarcoma 180 implants in mice. METHODS: We administered 5-FU at a dose of 0.75 mg/mouse six times per week and HBO at 2 atm absolute pressure for 90 min six times per week, both 17 times in total. In combination treatment, HBO was administered immediately after 5-FU injection. RESULTS: Over the treatment period, tumor diameter increased 277.8% in the untreated control group, 244.1% in the group receiving HBO monotherapy, 182.7% in the group receiving 5-FU monotherapy, and 138.5% in the group receiving combination therapy. Concomitant HBO increased accumulation of 5-FU in the tumors, liver, and kidneys, but not in the brain, of recipient animals. CONCLUSIONS: Based on the above results, we conclude that concomitant HBO enhances the effects of 5-FU.

[Apoptosis induced by interstitial irradiation with 32P glass microspheres combination with hyperthermia in mouse solid tumor S180].

OBJECTIVE: The aim of this study was to observe the changes of tumor cell apoptosis after interstitial irradiation combination with the hyperthermia treatment. METHODS: Twenty mice with solid tumor S180 were divided into four groups, including a control group which was given normal saline, and three experimental groups which were respectively applied with a hyperthermia treatment (bath water), interstitial irradiation with 32P glass microspheres, and the combined treatment of hyperthermia and interstitial irradiation. The terminal deoxynucleotidyl transferase mediated dUTP nick end labeling (TUNEL) method was used to determine the final apoptotic cells. RESULTS: The mean values of apoptotic indexes of these four groups were respectively 0.39, 0.53, 0.59 and 0.91. The apoptotic indexes of these experimental groups were significantly higher than that of the control group (P < 0.05). The apoptotic index of the combined treatment group was significantly higher than those of the hyperthermia group and the interstitial irradiation group (P < 0.05). CONCLUSION: Both the interstitial irradiated with 32P glass microspheres and hyperthermia (bath water) can induce the apoptosis of mouse solid tumor S180. It seems that there is a synergistic induction of apoptosis between interstitial irradiation and hyperthermia.

Therapeutic effects of moxibustion on experimental tumor.

This work investigated the therapeutic effects of the improved form of moxibustion (MT) on experimental tumor. Sarcoma 180 cells (1 x 10(7)) were transplanted into the subcutaneous tissue in the breast area of female ICR mice. Mice bearing a tumor were divided into one control and four experimental groups. The experimental groups were treated with MT for 1, 2, 3 and 4 times (abbreviated as MT1, MT2, MT3, MT4, respectively). This study showed that the experimental group treated with MT3 displayed the optimal therapeutic response. The longest mean survival time (87.8 days) within 120 days after treatment of MT3 significantly differed from the control group (60.2 days). In addition, uptake of 86Rb-radioactive tracer significantly decreased in tumors treated with MT3. The improved form of moxibustion used in this study is a reliable model of localized hyperthermia in tumor therapy.

Effects of hyperbaric oxygen on S-180 sarcoma in mice.

The contents of oxygen free radicals (OFRs) and malondialdehyde (MDA) in S-180 sarcoma tissues were measured in four groups of mice: an untreated normoxic group, a normoxic hyperbaric group, a hyperbaric oxygen group, and an HBO group treated with superoxide dismutase (SOD). Measurements were done by electron resonance and spectrophotometry, and observations were made on the volume, weight, necrosis incidence rate of sarcoma tissues, and mortality in all groups. The OFR and MDA content in sarcoma tissues in the HBO group was significantly higher than those of the control groups (P < 0.001); necrosis incidence of sarcoma tissues and the survival rate of mice were higher; the time required for necrosis was shorter, and the volume and weight of sarcoma tissues were smaller and lighter than those of the control groups (P < 0.01). The results suggest that SOD cannot completely eliminate OFRs produced by hyperbaric exposure, although the role of HBO in producing more OFRs can be counterbalanced by SOD to a certain degree. Apparently HBO can check the growth rate of sarcoma and accelerate the necrosis of S-180 sarcoma cells.

[Effects of moxibustion on the function of MDR gene product, P-glycoprotein (P-170)].

The experiments were performed on BABL/c mice with S-180R adriamycin resistant tumor cells. This animal model was used to analyze the drug accumulation in the S-180R cells by flow cytometer. The drug accumulation presents the pump activity of multidrug resistance (MDR) gene product P-glycoprotein (P-170) in the cell membrane, A weak inhibition was found when moxibustion at Guan-Yan point alone. And a very significant inhibition was observed in the presence of low-dosage of verapamil, but not at high dose. This study may develop a new way to research the mechanism of acupuncture and moxibustion at molecular level, and may be useful to overcome the anticancer drug resistance.

Longitudinal (T1) and transverse (T2) relaxation times of tissue water protons in mouse developing sarcoma 180-A: effect of hyperthermia.

In vitro studies on Swiss mice, inoculated with dead or live sarcoma 180-A ascites cells, were carried out to monitor the changes, if any, in the longitudinal (T1) and transverse (T2) relaxation times of tissue water protons following hyperthermic treatment and subsequent thermotolerance. Both relaxation processes exhibited biexponential relaxation curves. With increasing size of the tumours, the longitudinal relaxation behaviour changed from bi- to mono-exponential. This was not observed for the transverse relaxation phenomenon. Inoculation with either dead or live cells caused an immediate increase in the both relaxation times. In the case of dead cell inoculation, the increase lasted for only 24 h after which the relaxation times became the same as for the uninoculated controls. The transverse relaxation time increased as a result of exposure to hyperthermia. During development of thermotolerance, both the relaxation times decreased.

Response of mouse sarcoma-180 to bleomycin in combination with radiation and hyperthermia.

The response of a transplantable mouse tumor, S-180, grown intradermally in inbred Balb/c mice, to bleomycin (BLM), irradiation (RT) and hyperthermia (HT) was studied by observing tumor growth changes up to 120 days after treatment. BLM, at 20 mg/kg body weight, and 10 Gy gamma radiation individually produced identical tumor cure, while hyperthermia at 42 degrees C, 60' or 43 degrees C, 30' resulted in a higher tumor response. Treatment with 43 degrees C, 30' after BLM was more effective than hyperthermia after radiation in effecting tumor cure as well as in inducing regrowth delay. In the drug +HT combination the low drug dose was almost equal in effect as the higher drug dose when followed by 43 degrees C, 30'. Combining the three modalities resulted in 100% tumor cure without any local recurrence during the observation period. The micronucleus study 24 h after treatment indicated enhanced cytogenetic damage by the combination treatments.

Effects of hyperthermia on the metabolism of 5-fluorouracil in vitro.

The effects of hyperthermia (38-42 degrees C) on the metabolism of 5-fluorouracil (5-FU) were examined using Ehrlich tumour cells (E-cells) and Sarcoma-180 cells (S-180 cells) in vitro. A temperature-dependent elevation of the intracellular concentration of 5-FU was observed in both types of tumour cell after incubation with 5-FU. The levels of 5-fluorouridine (FUR) and 5-fluoro-2'-deoxyuridine (FdUR), which are active metabolites of 5-FU, increased significantly after treatment of cells with 5-FU and hyperthermia. The highest concentrations of these active metabolites were found when the cells were incubated at 39 degrees C. The levels of alpha-fluoro-beta-ureido-propionic acid (FUPA) and F-beta-alanine, which are inactive catabolic metabolites of 5-FU, also increased when the cells were incubated at 39 degrees C. The percentage inhibition of thymidilate synthetase (TS) activity remained high (about 60-70%) at 39 degrees C for 240 min. These results suggest that the optimal temperature for potentiating the intracellular metabolism of 5-FU, in terms of both activation and inactivation, is 39 degrees C in vitro.

Hyperthermia enhances the inhibition of tumor growth by 1-(2-tetrahydrofuryl)-5-fluorouracil/uracil (1:4) in tumors in mice and humans.

The cytotoxicity of several antitumor drugs is enhanced by hyperthermia (HT). Using mouse Sarcoma-180 (S-180) tumors, the authors examined the effects of 5-fluorouracil (5-FU) and a combined oral preparation of 1-(2-tetrahydrofuryl)-5-fluorouracil (FT) and uracil in a molar ratio of 1:4 (UFT), in combination with HT. The antitumor effect of 5-FU was not enhanced significantly by HT. Growth inhibition by UFT plus HT was significantly greater than that by UFT alone, whereas inhibition by UFT alone was significantly greater than that by 5-FU. The intracellular metabolism of 5-FU and FT in whole homogenates of S-180 cells, human tumor cell lines (SC-2 and Lu-99), and five fresh human tumor tissues also was investigated. Conversion of FT to 5-FU, phosphorylation, and degradation of 5-FU were assayed with [3H]FT or [3H]5-FU, and the products were separated by thin-layer chromatography. The conversion of FT to 5-FU and the phosphorylation of 5-FU were more rapid at 43 degrees C than at 37 degrees C, whereas the degradation of 5-FU to 2-fluoro-beta-alanine remained unchanged. This acceleration of the active metabolism of FT and 5-FU may be one explanation for the enhanced effect of UFT by HT.

Cytotoxicity of mitomycin C and carboquone combined with hyperthermia against hypoxic tumor cells in vitro.

Enhancement of the cytotoxicity of mitomycin C (MMC) and carboquone (CQ) by hypoxia at elevated temperature was examined using the SDI test of mouse Sarcoma 180 and Ehrlich cells and clonogenic assay of HeLa cells. When Sarcoma 180 and Ehrlich cells were incubated at 43 degrees C for 2-10 h, the hyperthermic effect was enhanced by hypoxia. The succinate dehydrogenase activity of the cells was reduced by hyperthermia to a greater extent in the presence of hypoxia (O2:5%) than under conditions of aeration (O2:20%). When the cells were exposed to various concentrations of MMC and CQ, under hypoxia, activity of the drugs was enhanced compared to the findings under conditions of aeration. The enhancement was prominent in case of drugs and hyperthermia combined. Clonogenicity of hypoxic HeLa cells was also reduced to a greater extent with this combination than in case of aerated cells. We tentatively speculate that hyperthermo-chemotherapy using MMC and CQ has a potential to attack selectively hypoxic cells present in a solid tumor.