Abscopal Effect of Radiotherapy Enhanced with Immune Checkpoint Inhibitors of Triple Negative Breast Cancer in 4T1 Mammary Carcinoma Model.

Local radiotherapy (RT) is important to manage metastatic triple-negative breast cancer (TNBC). Although RT primarily reduces cancer cells locally, this control can be enhanced by triggering the immune system via immunotherapy. RT and immunotherapy may lead to an improved systemic effect, known as the abscopal effect. Here, we analyzed the antitumor effect of combination therapy using RT with an anti-programmed cell death-1 (PD-1) antibody in primary tumors, using poorly immunogenic metastatic mouse mammary carcinoma 4T1 model. Mice were injected subcutaneously into both flanks with 4T1 cells, and treatment was initiated 12 days later. Mice were randomly assigned to three treatment groups: (1) control (no treatment with RT or immune checkpoint inhibitor (ICI)), (2) RT alone, and (3) RT+ICI. The same RT dose was prescribed in both RT-alone and RT+ICI groups as 10Gy/fx in two fractions and delivered to only one of the two tumor burdens injected at both sides of flanks. In the RT+ICI group, 200 µg fixed dose of PD-1 antibody was intraperitoneally administered concurrently with RT. The RT and ICI combination markedly reduced tumor cell growth not only in the irradiated site but also in non-irradiated sites, a typical characteristic of the abscopal effect. This was observed only in radiation-sensitive cancer cells. Lung metastasis development was lower in RT-irradiated groups (RT-only and RT+ICI groups) than in the non-irradiated group, regardless of the radiation sensitivity of tumor cells. However, there was no additive effect of ICI on RT to control lung metastasis, as was already known regarding the abscopal effect. The combination of local RT with anti-PD-1 blockade could be a promising treatment strategy against metastatic TNBC. Further research is required to integrate our results into a clinical setting.

Effects of Vitamin E on the immune system and tumor growth during radiotherapy.

PURPOSE: The purpose of this study is to evaluate the effects of Vitamin E (VE) on the immune system and tumor growth during radiotherapy (RT) in mice model. METHODS: C57BL/6NCrSlc mice were randomly distributed in four groups (control, VE alone, RT alone, and VE + RT). In the VE and VE + RT groups, VE was administered in the diet at 500 mg/kg. Radiation was delivered at 2 Gy in a single fraction on the whole body or at 6 Gy in three fractions locally in the RT and VE + RT groups. Changes in leukocytes and T lymphocytes were counted and compared between the four groups. To evaluate the effects on tumor growth, Ehrlich carcinoma cells were injected into the thighs of mice, and tumor volumes and growth inhibition rates were compared. RESULTS: The number of leukocytes was increased in the VE group compared with that in the control group. The magnitude of leukocyte recovery after RT was also increased by VE. This change was affected largely by alterations in lymphocytes and monocytes rather than that in granulocytes. Both CD4+ and CD8+ T lymphocytes were positively affected by VE. The tumor growth was inhibited not only by RT but also by VE alone. If RT was delivered with VE, tumor growth was markedly inhibited. CONCLUSION: VE could increase the number of leukocytes, primarily lymphocytes, even after RT was delivered. VE also inhibited the tumor growth in addition to RT. Thus, VE may be a useful radioprotective supplement in radiotherapy without inducing tumor growth.

Plant Enzymes Decrease Prostate Cancer Cell Numbers and Increase TNF-α In Vivo: A Possible Role in Immunostimulatory Activity.

Increased caloric intake and Westernized dietary choices may be contributing toward a recent rising trend of incidences of chronic lifestyle-related diseases. In this study, we evaluated the anticancer properties of Plant Enzyme Validux (PEV) using a mouse model. Five-week-old male C3H mice were randomly distributed into four experimental groups: Control, PEV only, 6Gy irradiation only, and PEV + 6Gy. PEV was orally administered daily at 500 mg/kg for 14 days prior to three rounds of 2Gy irradiation. We focused on the anticancer action and immunostimulatory effects of PEV with and without irradiation. Oncogene suppression was observed after PEV treatment as was an increase in TNF-α, suggesting an antitumor effect. PEV administration also appeared to reduce oxidative stress as evidenced by a decrease in lipid peroxidation. In addition, PEV confirmed radioprotective effect by radical blocking ability by radiation irradiation. Immunological responses to PEV administration were evidenced by an increase in number of total white blood cells and T lymphocytes. Immunotherapy is drawing more and more attention as a treatment for prostate cancer, suggesting that there will be a need for the identification of specific targets for prostate cancer and for more basic research on the genetic aspects of immunotherapy. Thus, PEV may be of use as a radioprotective supplement during radiotherapy for tumor treatment.

Cellular and Molecular Level Mechanisms against Electrochemical Cancer Therapy.

Electrochemical treatment (ECT) is a promising new way to induce tumor regression by flowing direct current into the cancer tissue. ECT was applied to different kinds of tumors in clinical studies and showed good results. In addition, basic research has almost not been done in the field of evaluation of efficacy, dose-response, and cytotoxicity. Therefore, the objective is to study the cellular mechanism in the antitumor effect of ECT and to contribute data of basic research of ECT. In the cell-level study, tumor cells (Sarcoma-180, Scc-7, Ehrlich Carcinoma) were studied using ICR mice and C3H mice. In the study group, pH values of control, 10mA × 150secs, 10mA × 300secs, and 10mA × 600secs groups were measured five times each. In histological level studies, ECT was performed on tumors inoculated on the upper part of the right foot of C3H mice. In each group, mice were sacrificed by cervical dislocation 6, 12, and 24 hrs after ECT treatment, and tumors were removed. The excised tumor was fixed in tissue with 10% formalin, and HE staining and apoptosis antibody staining were carried out from the obtained tissue section and observation. In the study at the cellular level, statistically significant differences were observed in all ECT groups in Sarcoma in the tumor growth measurement study compared with the control group. Statistically significant differences were also observed in Scc-7 in all ECT groups compared to the control group. In the intratumoral pH measurement study, there was a statistically significant difference between the anode and the cathode in each group compared to the control group. In the examination at the histological level, microscopic observation of a slide stained with apoptosis antibody with a magnification of 400 times showed that 6hrs after ECT it was stronger and then decreased. By performing ECT, a weak current flows in the living body. As a result, changes in tissue pH, generation of gas, etc. occur. In this study, it was also confirmed that the intratumor pH value becomes strongly acidic on the anode side and strongly alkaline on the cathode side. In addition, this study confirmed the occurrence of gas during treatment of ECT. Changes in the pH and the like cause changes in the environment in the cell, denaturation of proteins, apoptosis, and necrosis. In this study, a significant increase in apoptosis was confirmed in each ECT group compared to the control group. Treatment effects by ECT were also observed in tumor growth measurement studies and tumor weight measurement studies. From these research results, ECT is considered to be effective as a tumor treatment method.

Subchronic Oral Dose Toxicity Study of Enterococcus Faecalis 2001 (EF 2001) in Mice.

As a part of general toxicity studies of Enterococcus Faecalis 2001 (EF 2001) prepared using heat-treatment bacillus mort body EF 2001 in mice, this study examined the toxicity of EF 2001 in single and repeated administrations following the previous report in order to apply this product to preventive medicine. The safety of oral ingestion of EF 2001 was examined in 6-week-old male and female ICR mice with 1,000 mg/kg, 3,000 mg/kg and 5,000 mg/kg body weight/day administrated by gavage of the maximum acceptable dose of EF 2001. The study was conducted using distilled water as a control following the methods for general toxicity studies described in the "Guidelines for Non-clinical Studies of Pharmaceutical Products 2002". As a control, 1) observation of general conditions, 2) measurement of body weight, 3) determination of food consumption, 4) determination of water consumption, 5) blood test and urinalysis and 6) pathological examination were performed for the administration of EF 2001. Mice received EF 2001 for 13 weeks and results were compared with those of the control group that received distilled water. The results of the above examinations revealed no significant differences between control and EF 2001 groups for both males and females. Thus, no notable toxicity was confirmed with single and repeated oral administrations of EF 2001. Oral administration in the above doses did not result in abnormal symptoms or death during the observation period. No abnormalities in blood cell count or organ weights were seen. Without any evidence of toxicity to cells and organs, EF 2001 is speculated to not adversely affect living organisms. The 50% lethal dose of EF 2001 with oral administration in mice is estimated to be greater than 5,000 mg/kg body weight/day for both male and female mice. Therefore, LD50 value for animals was 5,000 mg/kg or more.

Pharmaceutical Production of Anti-tumor and Immune-potentiating Enterococcus faecalis-2001 ß-glucans: Enhanced Activity of Macrophage and Lymphocytes in Tumor-implanted Mice.

BACKGROUND: Enterococcus faecalis 2001 is a probiotic lactic acid bacterium and has been used as a biological response modifier (BRM). From physiological limitation of bacterial preservation in storage and safety, the live E. faecalis 2001 has been heat-treated and the BRM components containing high level of ß-glucan, named EF-2001, were prepared. METHOD: The heat-treated EF-2001 has been examined for the antioxidative potential for radical scavenging and anti-tumor activities as well as immune-enhancing response in mice. Lymphocyte versus polymorphonuclear leukocyte ratio was increased in mice upon treatment with EF-2001. The number of lymphocytes was increased in the EF-2001-treated group. In the mice bearing two different Ehrlich solid and Sarcoma-180 carcinomas, the treatment with EF-2001 resulted in anti-tumor action. Tumor-suppressive capacity upon treatment with EF-2001 was significantly increased compared to normal controls. RESULTS: During the time interval administration of 5 weeks between the priming and secondary administration of EF-2001, the expression and production levels of TNF-α were also observed in the EF- 2001-administered mice. Additionally, anti-tumor activity examined with the intravenous administration of EF 2001 with a 34 times interval was also observed, as the growth of Sarcoma180 cells was clearly inhibited by the EF-2001. CONCLUSION: From the results, it was suggested that the immune response is enhanced due to antioxidative activity caused by the EF-2001 and anti-tumor activity by NK cells and TNF-α.

Concurrent Chemoradiation with Low-Dose Weekly Cisplatin in Locally Advanced Stage IV Head and Neck Squamous Cell Carcinoma.

PURPOSE: Concurrent chemoradiation (CRT) with 3-weekly doses of cisplatin is a standard treatment for loco-regionally advanced head and neck squamous cell carcinoma (HNSCC). However, treatment with 3-weekly doses of cisplatin is often associated with several adverse events. Therefore, we conducted this retrospective analysis to determine the efficacy and tolerance of CRT with a low weekly dose of cisplatin in stage IV HNSCC patients. MATERIALS AND METHODS: Medical records of patients who were diagnosed with stage IV HNSCC and received concurrent CRT were analyzed. All patients were treated weekly with cisplatin at 20-30 mg/m(2) until radiotherapy was completed. RESULTS: A total of 35 patients were reviewed. Median follow up was 10.7 months (range, 1.7 to 90.5 months), the median radiation dose was 7,040 cGy, and the median dose of cisplatin received was 157 mg/m(2). Eleven patients received docetaxel combination chemotherapy. Overall, 25 patients (71.4%) achieved complete response (CR), eight (22.9%) showed partial response. The median overall survival was 42.7 months, the 3-year survival rate was 51.2% and the 3 year disease-free survival rate was 72.8%. Overall survival was improved in patients who achieved CR relative to others (59.7 months vs. 13.4 months; p=0.008). There were significant differences in survival between patients who received docetaxel combination and cisplatin alone (51.8 months vs. 7.9 months; p=0.009). Grade 3-4 adverse events included stomatitis (82.9%), dermatitis (22.9%), infection (11.4%), dysphagia (8.6%), and neutropenia (5.7%). CONCLUSION: CRT with low dose weekly cisplatin is likely effective and tolerable, even in patients with locally advanced-stage IV HNSCC.

Effect of early chemoradiotherapy in patients with limited stage small cell lung cancer.

PURPOSE: We evaluated the effect of early chemoradiotherapy on the treatment of patients with limited stage small cell lung cancer (LS-SCLC). MATERIALS AND METHODS: Between January 2006 and December 2011, thirty-one patients with histologically proven LS-SCLC who were treated with two cycles of chemotherapy followed by concurrent chemoradiotherapy and consolidation chemotherapy were retrospectively analyzed. The chemotherapy regimen was composed of etoposide and cisplatin. Thoracic radiotherapy consisted of 50 to 60 Gy (median, 54 Gy) given in 5 to 6.5 weeks. RESULTS: The follow-up period ranged from 5 to 53 months (median, 22 months). After chemoradiotherapy, 35.5% of the patients (11 patients) showed complete response, 61.3% (19 patients) showed partial response, 3.2% (one patient) showed progressive disease, resulting in an overall response rate of 96.8% (30 patients). The 1-, 2-, and 3-year overall survival (OS) rates were 66.5%, 41.0%, and 28.1%, respectively, with a median OS of 21.3 months. The 1-, 2-, and 3-year progression free survival (PFS) rates were 49.8%, 22.8%, and 13.7%, respectively, with median PFS of 12 months. The patterns of failure were: locoregional recurrences in 29.0% (nine patients), distant metastasis in 9.7% (three patients), and both locoregional and distant metastasis in 9.7% (three patients). Grade 3 or 4 toxicities of leukopenia, anemia, and thrombocytopenia were observed in 32.2%, 29.0%, and 25.8%, respectively. Grade 3 radiation esophagitis and radiation pneumonitis were shown in 12.9% and 6.4%, respectively. CONCLUSION: We conclude that early chemoradiotherapy for LS-SCLC provides feasible and acceptable local control and safety.

Effects of drinking hydrogen-rich water on the quality of life of patients treated with radiotherapy for liver tumors.

BACKGROUND: Cancer patients receiving radiotherapy often experience fatigue and impaired quality of life (QOL). Many side effects of radiotherapy are believed to be associated with increased oxidative stress and inflammation due to the generation of reactive oxygen species during radiotherapy. Hydrogen can be administered as a therapeutic medical gas, has antioxidant properties, and reduces inflammation in tissues. This study examined whether hydrogen treatment, in the form of hydrogen-supplemented water, improved QOL in patients receiving radiotherapy. METHODS: A randomized, placebo-controlled study was performed to evaluate the effects of drinking hydrogen-rich water on 49 patients receiving radiotherapy for malignant liver tumors. Hydrogen-rich water was produced by placing a metallic magnesium stick into drinking water (final hydrogen concentration; 0.55~0.65 mM). The Korean version of the European Organization for Research and Treatment of Cancer's QLQ-C30 instrument was used to evaluate global health status and QOL. The concentration of derivatives of reactive oxidative metabolites and biological antioxidant power in the peripheral blood were assessed. RESULTS: The consumption of hydrogen-rich water for 6 weeks reduced reactive oxygen metabolites in the blood and maintained blood oxidation potential. QOL scores during radiotherapy were significantly improved in patients treated with hydrogen-rich water compared to patients receiving placebo water. There was no difference in tumor response to radiotherapy between the two groups. CONCLUSIONS: Daily consumption of hydrogen-rich water is a potentially novel, therapeutic strategy for improving QOL after radiation exposure. Consumption of hydrogen-rich water reduces the biological reaction to radiation-induced oxidative stress without compromising anti-tumor effects.

Drinking hydrogen water ameliorated cognitive impairment in senescence-accelerated mice.

Hydrogen has been reported to have neuron protective effects due to its antioxidant properties, but the effects of hydrogen on cognitive impairment due to senescence-related brain alterations and the underlying mechanisms have not been characterized. In this study, we investigated the efficacies of drinking hydrogen water for prevention of spatial memory decline and age-related brain alterations using senescence-accelerated prone mouse 8 (SAMP8), which exhibits early aging syndromes including declining learning ability and memory. However, treatment with hydrogen water for 30 days prevented age-related declines in cognitive ability seen in SAMP8 as assessed by a water maze test and was associated with increased brain serotonin levels and elevated serum antioxidant activity. In addition, drinking hydrogen water for 18 weeks inhibited neurodegeneration in hippocampus, while marked loss of neurons was noted in control, aged brains of mice receiving regular water. On the basis of our results, hydrogen water merits further investigation for possible therapeutic/preventative use for age-related cognitive disorders.