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Radiotherapy is routinely used for the treatment of head and neck squamous cell carcinoma (HNSCC). However, the therapeutic efficacy is usually reduced by acquired radioresistance and locoregional recurrence. In this study, The Cancer Genome Atlas (TCGA) analysis showed that radiotherapy upregulated the miR-182/96/183 cluster and that miR-182 was the most significantly upregulated. Overexpression of miR-182-5p enhanced the radiosensitivity of HNSCC cells by increasing intracellular reactive oxygen species (ROS) levels, suggesting that expression of the miR-182 family is beneficial for radiotherapy. By intersecting the gene targeting results from three microRNA target prediction databases, we noticed that sestrin2 (SESN2), a molecule resistant to oxidative stress, was involved in 91 genes predicted in all three databases to be directly recognized by miR-182-5p. Knockdown of SESN2 enhanced radiation-induced ROS and cytotoxicity in HNSCC cells. In addition, the radiation-induced expression of SESN2 was repressed by overexpression of miR-182-5p. Reciprocal expression of the miR-182-5p and SESN2 genes was also analyzed in the TCGA database, and a high expression of miR-182-5p combined with a low expression of SESN2 was associated with a better survival rate in patients receiving radiotherapy. Taken together, the current data suggest that miR-182-5p may regulate radiation-induced antioxidant effects and mediate the efficacy of radiotherapy.

Metastasis is the leading cause of death in non-small cell lung cancer patients (NSCLC). Actin cytoskeletal rearrangement is frequently accompanied by cancer cell invasion and metastasis induced by the epithelial-mesenchymal transition (EMT). The expression levels of the actin-associated protein cofilin-1 and the crucial EMT molecule Twist-1 in NSCLC tissues were investigated in this work. Immunohistochemical (IHC) staining was used to identify 67.4% of tissue locations that had reciprocal amounts of cofilin-1 and Twist-1 using lung cancer tissue arrays. This reciprocal expression pattern was also found in 10 out of 15 NSCLC cell lines and 21 out of 25 clinicopathological NSCLC tissue sections. Furthermore, in tissue arrays and clinicopathological tissue samples, high levels of cofilin-1 and low levels of Twist-1 accounted for 80% and 71.5% of the reciprocal expression pattern, respectively. This pattern was also found in normal lung tissues, lung cancer tissues in stages I and II, and NSCLC tissues with adenocarcinoma subtypes. Despite the fact that cofilin-1 and Twist-1 were expressed in opposite directions, there was a positive association between the two proteins in normal lung tissues and lung tumor tissues. In addition, induced expression of cofilin-1 in H1299 NSCLC cells may suppress Twist-1 expression. A public microarray dataset with a maximum of 1,926 NSCLC samples were made accessible through an online Kaplan-Meier survival analytic tool. The investigators discovered that high levels of expression of both the cofilin-1 and Twist-1 genes were linked to lower NSCLC patient survival, particularly in the adenocarcinoma subtype. The multivariate Cox regression model was used in the analysis. Even though more data is required to confirm the reciprocal relationship between cofilin-1 and Twist-1 expression levels and NSCLC survival rates, it could be a useful indication of NSCLC progression.

Hypopharyngeal cancer (HPC) accounts for the lowest survival rate among all types of head and neck cancers (HNSCC). However, the therapeutic approach for HPC still needs to be investigated. In this study, a theranostic 188Re-liposome was prepared to treat orthotopic HPC tumors and analyze the deregulated microRNA expressive profiles. The therapeutic efficacy of 188Re-liposome on HPC tumors was evaluated using bioluminescent imaging followed by next generation sequencing (NGS) analysis, in order to address the deregulated microRNAs and associated signaling pathways. The differentially expressed microRNAs were also confirmed using clinical HNSCC samples and clinical information from The Cancer Genome Atlas (TCGA) database. Repeated doses of 188Re-liposome were administrated to tumor-bearing mice, and the tumor growth was apparently suppressed after treatment. For NGS analysis, 13 and 9 microRNAs were respectively up-regulated and down-regulated when the cutoffs of fold change were set to 5. Additionally, miR-206-3p and miR-142-5p represented the highest fold of up-regulation and down-regulation by 188Re-liposome, respectively. According to Differentially Expressed MiRNAs in human Cancers (dbDEMC) analysis, most of 188Re-liposome up-regulated microRNAs were categorized as tumor suppressors, while down-regulated microRNAs were oncogenic. The KEGG pathway analysis showed that cancer-related pathways and olfactory and taste transduction accounted for the top pathways affected by 188Re-liposome. 188Re-liposome down-regulated microRNAs, including miR-143, miR-6723, miR-944, and miR-136 were associated with lower survival rates at a high expressive level. 188Re-liposome could suppress the HPC tumors in vivo, and the therapeutic efficacy was associated with the deregulation of microRNAs that could be considered as a prognostic factor.

// Liang-Ting Lin 1, 10, * , Shin-Yi Liu 2, * , Jyh-Der Leu 3, 4, * , Chun-Yuan Chang 1 , Shih-Hwa Chiou 5, 6, 7 , Te-Chang Lee 7, 8 and Yi-Jang Lee 1, 9 1 Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, Taiwan 2 Department of Radiation Oncology, MacKay Memorial Hospital, Taipei, Taiwan 3 Division of Radiation Oncology, Taipei City Hospital Ren Ai Branch, Taipei, Taiwan 4 Institute of Neuroscience, National Chengchi University, Taipei, Taiwan 5 Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei, Taiwan 6 Institute of Clinical Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan 7 Institute of Pharmacology, National Yang-Ming University, Taipei, Taiwan 8 Institute of Biomedical Sciences, Academia Sinica, Taipei, Taiwan 9 Biophotonics and Molecular Imaging Research Center (BMIRC), National Yang-Ming University, Taipei, Taiwan 10 Current address: Department of Health Technology and Informatics, The Hong Kong Polytechnic University, Hong Kong * These authors have contributed equally to this work Correspondence to: Te-Chang Lee, email: bmtcl@ibms.sinica.edu.tw Yi-Jang Lee, email: yjlee2@ym.edu.tw Keywords: arsenic trioxide; sestrin 2; miR-182; oxidative stress; anti-oxidant effect Received: April 12, 2017 Accepted: February 24, 2018 Published: March 23, 2018 ABSTRACT Arsenic trioxide (ATO) is a traditional Chinese medicine that can induce oxidative stress for treatment of cancer cells. However, ATO may generate anti-oxidative responses to compromise the cytotoxic effect, but the underlying mechanisms remain unclear. Here we found that ATO could inhibit miR-182-5p expression in patient-derived primary S1 glioblastoma (GBM) cells accompanied by up-regulation of Sestrin-2 ( SESN2 ) mRNA, a known anti-oxidant molecule. This phenomenon was also detected in a U87MG glioma cell line, human lung adenocarcinoma H1299 cell line and A549 cell line. Pretreatment with a free radical scavenger N-acetylcysteine (NAC) reduced the oxidative stress induced by ATO. Concomitantly, ATO mediated suppression of miR-182-5p and enhancement of SESN2 expression were also compromised. The MTT assay further showed that ATO induced cytotoxicity was enhanced by transfection of miR-182-5p mimics. Overexpression of miR-182-5p mimics significantly suppressed the expression of SENS2 and a firefly luciferase reporter gene fused to 3’- untranslated region (UTR) of SESN2 mRNA. Use of ribonucleoprotein immunoprecipitation (RNP-IP), ATO mediated suppression of miR-182-5p led to the stabilization of SESN2 mRNA as a result of Argonaute-2 (AGO2) dependent gene silencing. Furthermore, high expression of miR-182-5p and low expression of SESN2 mRNA tend to be associated with longer survival of glioma or lung cancer patients using public available gene expression datasets and online tools for prediction of clinical outcomes. Taken together, current data suggest that the miR-182-5p/SENS2 pathway is involved in ATO induced anti-oxidant responses, which may be important for the design of novel strategy for cancer treatment.

The current study aims to investigate whether MDM2-SNP309 and p53R72P polymorphisms were associated with the risk of bladder cancer in Mongolian populations. These polymorphisms were evaluated in 79 controls and 63 bladder cancer cases using a PCR-restriction fragment length polymorphism assay, followed by analysis using multivariate logistic regression model and the Kaplan-Meier model to determine the odds ratio (OR) and age at onset of bladder cancer, respectively. The results revealed that the homozygous (G/G) genotype of MDM2-SNP309 increased the risk of bladder cancer compared to the wild-type (T/T) genotype [OR=1.629; 95% confidence interval (CI)=0.622–4.266] among Mongolians. On the other hand, the homozygous (P/P) genotype of p53R72P tended to protect the population from bladder cancer compared with the wild-type (R/R) genotype (OR=0.445; 95% CI=0.1727–2.147). It also showed that G/G genotype of MDM2-SNP309 increased the risk of bladder cancer when combined with the R/R genotype of p53R72P (OR=3.355; 95% CI=0.3914–28.766). Stratification by smoking and history of chronic urinary tract diseases tended towards increasing the risk association of the G/G (OR=2.3704; 95% CI=0.4308–3.044) and T/G genotypes (OR=5; 95% CI=0.8442–30.4088) of MDM2-SNP309 with bladder cancer, respectively. The protective role of P/P of p53R72P remained following stratification. MDM2-SNP309 and p53R72P were not involved in early age onset of bladder cancer in Mongolian patients. Taken together, MDM2-SNP309 and p53R72P had no significant association with bladder cancer in Mongolian patients. The two SNPs were also not able to predict early age at onset of bladder cancer.

Radiation is a widely used therapeutic method for treating breast cancer. N-dihydrogalactochitosan (GC), a biocompatible immunostimulant, is known to enhance the effects of various treatment modalities in different tumor types. However, whether GC can enhance the radiosensitivity of cancer cells remains to be explored. In this study, triple-negative murine 4T1 breast cancer cells transduced with multi-reporter genes were implanted in immunocompetent Balb/C mice to track, dissect, and identify liver-metastatic 4T1 cells. These cells expressed cancer stem cell (CSC) -related characteristics, including the ability to form spheroids, the expression of the CD44 marker, and the increase of protein stability. We then ex vivo investigated the potential effect of GC on the radiosensitivity of the liver-metastatic 4T1 breast cancer cells and compared the results to those of parental 4T1 cells subjected to the same treatment. The cells were irradiated with increased doses of X-rays with or without GC treatment. Colony formation assays were then performed to determine the survival fractions and radiosensitivity of these cells. We found that GC preferably increased the radiosensitivity of liver-metastatic 4T1 breast cancer cells rather than that of the parental cells. Additionally, the single-cell DNA electrophoresis assay (SCDEA) and &gamma, H2AX foci assay were performed to assess the level of double-stranded DNA breaks (DSBs). Compared to the parental cells, DNA damage was significantly increased in liver-metastatic 4T1 cells after they were treated with GC plus radiation. Further studies on apoptosis showed that this combination treatment increased the sub-G1 population of cells, but not caspase-3 cleavage, in liver-metastatic breast cancer cells. Taken together, the current data suggest that the synergistic effects of GC and irradiation might be used to enhance the efficacy of radiotherapy in treating metastatic tumors.

Fisetin (3,7,3′,4′-tetrahydroxyflavone), which belongs to the flavonoid group of polyphenols and is found in a wide range of plants, has been reported to exhibit a number of biological activities in human cancer cells, including antioxidant, anti-inflammatory, antiangiogenic, anti-invasive and antiproliferative effects. Although previous in vitro studies have shown that fisetin treatment increases the apoptotic rate and enhances the radiosensitivity of human colorectal cancer cells, the in vivo effects of fisetin on tumor growth remain unclear. In the present study a murine xenograft tumor model was employed to investigate the therapeutic effects of fisetin in combination with radiation on CT-26 colon cancer cells and human HCT116 colorectal cancer cells. This revealed that intratumoral injection of fisetin significantly suppressed the growth of CT-26 tumors compared with the untreated control group, but had little effect on the growth of HCT116 tumors. However, fisetin in combination with 2-Gy radiation enhanced tumor suppressor activity in murine colon and human colorectal xenograft tumors, as compared with 2-Gy fractionated radiation administered alone for 5 days and fisetin alone. Interestingly, fisetin downregulated the expression of the oncoprotein securin in a p53-independent manner. However, securin-null HCT116 tumors showed only moderate sensitivity to fisetin treatment, and the combination of fisetin and radiation did not significantly suppress securin-null HCT116 tumor growth compared with normal HCT116 tumors. Therefore, the role of securin in mediating the effect of fisetin on colorectal cancer growth warrants further investigation. In conclusion, the results of the current study provide important preclinical data for evaluating the efficacy of fisetin and radiation combination treatment as an adjuvant chemoradiotherapy for human colorectal cancers.

// Liang-Ting Lin 1, 2 , Chun-Yuan Chang 1 , Chih-Hsien Chang 3 , Hsin-Ell Wang 1 , Shih-Hwa Chiou 2, 4, 5 , Ren-Shyan Liu 1 , Te-Wei Lee 3 , Yi-Jang Lee 1, 6 1 Department of Biomedical Imaging and Radiological Sciences, National Yang-Ming University, Taipei, Taiwan 2 Department of Medical Research and Education, Taipei Veterans General Hospital, Taipei, Taiwan 3 Isotope Application Division, Institute of Nuclear Energy Research, Taoyuan, Taiwan 4 Institute of Clinical Medicine, School of Medicine, National Yang-Ming University, Taipei, Taiwan 5 Institute of Pharmacology, National Yang-Ming University, Taipei, Taiwan 6 Biophotonics and Molecular Imaging Research Center (BMIRC), National Yang-Ming University, Taipei, Taiwan Correspondence to: Te-Wei Lee, email: tewei123456@gmail.com Yi-Jang Lee, email: yjlee2@ym.edu.tw Keywords: 188 Re-liposome, HNSCC, orthotopic tumor model, microarray analysis, let-7 microRNA Received: May 20, 2016 Accepted: August 13, 2016 Published: August 29, 2016 ABSTRACT Human head and neck squamous cell carcinoma (HNSCC) is usually treated by surgical resection with adjuvant radio-chemotherapy. In this study, we examined whether the radiopharmaceutical 188 Re-liposome could suppress the growth of HNSCC followed by an investigation of molecular mechanisms. The orthotopic HNSCC tumor model was established by human hypopharyngeal FaDu carcinoma cells harboring multiple reporter genes. The drug targeting and therapeutic efficacy of 188 Re-liposome were examined using in vivo imaging, bio-distribution, pharmacokinetics, and dosimetry. The results showed that 188 Re-liposome significantly accumulated in the tumor lesion compared to free 188 Re. The circulation time and tumor targeting of 188 Re-liposome were also longer than that of free 188 Re in tumor-bearing mice. The tumor growth was suppressed by 188 Re-liposome up to three weeks using a single dose treatment. Subsequently, microarray analysis followed by Ingenuity Pathway Analysis (IPA) showed that tumor suppressor let-7 microRNA could be an upstream regulator induced by 188 Re-liposome to regulate downstream genes. Additionally, inhibition of let-7i could reduce the effects of 188 Re-liposome on suppression of tumor growth, suggesting that let-7 family was involved in 188 Re-liposome mediated suppression of tumor growth in vivo . Our data suggest that 188 Re-liposome could be a novel strategy for targeting HNSCC partially via induction of let-7 microRNA.

Colorectal cancer is one of the major causes of cancer-related death in Taiwan and worldwide. Patients with peritoneal metastasis from colorectal cancer have reduced overall survival and poor prognosis. Hybrid protein-inorganic nanoparticle systems have displayed multifunctional applications in solid cancer theranostics. In this study, a gold nanocore-encapsulated human serum albumin nanoparticle (Au@HSANP), which is a hybrid protein-inorganic nanoparticle, and its radioactive surrogate 111In-labeled Au@HSANP (111In-Au@HSANP), were developed and their biological behaviors were investigated in a tumor/ascites mouse model. 111In-Au@HSANP was injected either intravenously (iv) or intraperitoneally (ip) in CT-26 tumor/ascites-bearing mice. After ip injection, a remarkable and sustained radioactivity retention in the abdomen was noticed, based on microSPECT images. After iv injection, however, most of the radioactivity was accumulated in the mononuclear phagocyte system. The results of biodistribution indicated that ip administration was significantly more effective in increasing intraperitoneal concentration and tumor accumulation than iv administration. The ratios of area under the curve (AUC) of the ascites and tumors in the ip-injected group to those in the iv-injected group was 93 and 20, respectively. This study demonstrated that the ip injection route would be a better approach than iv injections for applying gold-albumin nanoparticle in peritoneal metastasis treatment.

Metastasis is the primary cause of mortality in patients with non‑small cell lung cancer (NSCLC). Actin cytoskeletal reorganization is usually accompanied by the epithelial‑mesenchymal transition (EMT)‑induced invasion and metastasis of cancer cells. In the present study, expression levels of the actin‑associated protein cofilin‑1 and of the pivotal EMT molecule Twist‑1 were determined in NSCLC tissues. Using lung cancer tissue arrays, the identification of 67.4% of tissue spots that exhibited reciprocal levels of cofilin‑1 and Twist‑1 was achieved by immunohistochemical (IHC) staining. This reciprocal expression pattern was also detected in 21 out of 25 clinicopathological NSCLC tissue sections, and in 10 out of 15 NSCLC cell lines. In addition, high levels of cofilin‑1 and low levels of Twist‑1 accounted for 80 and 71.5% of the reciprocal expression pattern in tissue arrays and clinicopathological tissue samples, respectively. This pattern was also detected in normal lung tissues, stage I and II lung cancer tissues, and adenocarcinoma subtypes of NSCLC tissues. Although cofilin‑1 and Twist‑1 were expressed inversely, a positive correlation of these two proteins was present in normal lung tissues and lung tumor tissues. Furthermore, enforced expression of cofilin‑1 suppressed the expression level of Twist‑1 in NSCLC H1299 cells. An on‑line Kaplan‑Meier survival analytic tool allowed access to a public microarray dataset with a maximum of 1,926 NSCLC samples. The analysis revealed that high expression levels of both cofilin‑1 (CFL1) and Twist‑1 (TWIST1) genes were associated with decreased survival of NSCLC patients, notably with regard to the adenocarcinoma subtype. The analysis was conducted using the multivariate Cox regression model. Although the reciprocal association of the expression levels of cofilin‑1 and Twist‑1 with the survival rate of NSCLC patients requires additional information, it may be a significant indicator of the progression of NSCLC.

Despite standard treatment, about 70% of ovarian cancer will recur. Cancer stem cells (CSCs) have been implicated in the drug-resistance mechanism. Several drug resistance mechanisms have been proposed, and among these, autophagy plays a crucial role for the maintenance and tumorigenicity of CSCs. Compared to their differentiated counterparts, CSCs have been demonstrated to display a significantly higher level of autophagy flux. Moreover, mitophagy, a specific type of autophagy that selectively degrades excessive or damaged mitochondria, is shown to contribute to cancer progression and recurrence in several types of tumors. Nanomedicine has been shown to tackle the CSCs problem by overcoming drug resistance. In this work, we developed a nanomedicine, 188Re-liposome, which was demonstrated to target autophagy and mitophagy in the tumor microenvironment. Of note, the inhibition of autophagy and mitophagy could lead to significant tumor inhibition in two xenograft animal models. Lastly, we presented two cases of recurrent ovarian cancer, both in drug resistance status that received a level I dose from a phase I clinical trial. Both cases developing drug resistance showed drug sensitivity to 188Re-liposome. These results suggest that inhibition of autophagy and mitophagy by a nanomedicine may be a novel strategy to overcome drug resistance in ovarian cancer.

Non–small cell lung cancer (NSCLC) is a highly morbid and mortal cancer type that is difficult to eradicate using conventional chemotherapy and radiotherapy. Little is known about whether radionuclide-based pharmaceuticals can be used for treating NSCLC. Here we embedded the therapeutic radionuclide 188Re in PEGylated (PEG is polyethylene glycol) liposomes and investigated the biodistribution, pharmacokinetics, and therapeutic efficacy of this nanoradiopharmaceutical on NSCLC using a xenograft lung tumor model and the reporter gene imaging techniques. Methods: Human NSCLC NCI-H292 cells expressing multiple reporter genes were used in this study. 188Re was conjugated to N,N-bis(2-mercaptoethyl)-N′,N′-diethylethylenediamine (BMEDA) and loaded into the PEGylated liposome to form a 188Re-liposome. The tumor growth rates and localizations were confirmed using bioluminescent imaging and SPECT/CT after the 188Re-BMEDA or 188Re-liposome was intravenously injected. The accumulation of the nanodrug in various organs was determined by the biodistribution analysis and the nano-SPECT/CT system. The pharmacokinetic and dosimetric analyses were further determined using WinNonlin and OLINDA/EXM, respectively. Results: The biodistribution and nano-SPECT/CT imaging showed that PEGylated 188Re-liposome could efficiently accumulate in xenograft tumors formed by NCI-H292 cells that were subcutaneously implanted in nude mice. Pharmacokinetic analysis also showed that the retention of 188Re-liposome was longer than that of 188Re-BMEDA. In an orthotopic tumor model, ex vivo γ counting revealed that the uptake of 188Re-liposome was detected in tumor lesions but not in surrounding normal lung tissues. Moreover, we evaluated the therapeutic efficacy using bioluminescent imaging and showed that the lung tumor growth was suppressed but not eradicated by 188Re-liposome. The life span of 188Re-liposome–treated mice was 2-fold longer than that of untreated control mice. Conclusion: The results of biodistribution, pharmacokinetics, estimated dosimetry, nano-SPECT/CT, and bioluminescent imaging suggest that the PEGylated liposome–embedded 188Re could be used for the treatment of human lung cancers.

Aim Effects of radiofrequency ablation (RFA) combining immunoadjuvant glycated chitosan (GC) on tumor control and potent cytokine responses were investigated in a syngeneic breast tumor model. Materials and methods Murine 4T1 breast carcinoma cells harboring the luciferase reporter gene were used to evaluate the tumor growth rate and metastasis in vivo using bioluminescent imaging. Plasma of RFA/GC-treated tumor-bearing mice was collected for ex vivo cytotoxicity analysis and mouse chemokine array assays. Results Tumor growth and systemic metastasis were suppressed by combined RFA and GC when tumor size reached 300 mm3, not detected, however, when tumor size reached 800 mm3 The survival rate of mice bearing small tumors was also higher than that of large ones after RFA-GC treatment. Plasma extracted from RFA-GC-treated small tumor-bearing mice exhibited cytotoxicity on cultured 4T1 cells. Moreover, reduced tumor growth-related cytokines and increased antitumor-related cytokines were detected in the plasma collected. Conclusion RFA combining GC could control tumor progression with induced potent antitumor cytokine responses.

Ischemic shock and acute kidney injury (AKI) are the primary causes of high mortality in the intensive care unit (ICU) patients. In a rat model, ischemia is able to disrupt the actin cytoskeleton of proximal tubule cells. This effect is associated with the expression and excretion of actin depolymerizing factor (ADF)/cofilin. However, the human evidence of ADF/cofilin excreted in ICU patients with ischemic shock and/or AKI remains to be addressed. Here we developed a 96-well high-throughput, localized surface plasmon-coupled fluorescence biosensor (HT-LSPCFB) combining a sandwich immunoassay to measure the urine cofilin-1 in 57 ICU patients and 8 healthy controls. A linear relationship between 1 and 10 5 pg/mL of human cofilin-1 recombinant protein was determined ( R 2 = 0.9845) in this study. The highest normalized cofilin-1 levels obtained in the ICU patients and healthy adults were 1.985 and 0.726, respectively. The mean normalized cofilin-1 level of total ICU patients (0.7403) was also significantly higher than that of healthy adults (0.4759) ( p = 0.0052). An examination of the receiver operating characteristic (ROC) curve and area under curve (AUC) showed that cofilin-1 is acceptable for assessing the ICU patients (AUC = 0.775) and shock (AUC = 0.713), but not for AKI (AUC = 0.681). Therefore, the HT-LSPCFB is suitable for detecting the urine cofilin-1 which potentially becomes a prognostic factor for ICU patients with shock.

Oral squamous cell carcinoma (OSCC) is the most common malignancy of the oral cavity; however the treatment approaches are still unsatisfactory. We used a luciferase-transfected animal model to evaluate the therapeutic effects of curcumin. Human oral squamous cell carcinoma SAS cell line was stably transfected with luc gene, named SAS/luc cells. For the in vivo study, they were inoculated subcutaneously to 6-week-old male NOD/SCID mice which were separated into four groups for intraperitoneal injection (i.p.) of curcumin: control, daily with 35 mg/kg, 70 mg/kg every 2 days, and 100 mg/kg every 3 days. We applied SAS/luc bearing animal model and bioluminescent imaging (BLI) to study the inhibition effect of curcumin on tumor growth. The cytotoxic effect of curcumin on SAS/luc cells was mainly at G2/M phase and a significant dose dependent increase of the apoptotic SAS/luc cells as represented by sub-G1 phase was shown. Therapeutic efficacy evaluated by both caliper assay and BLI showed a significant difference between curcumin-treated mice and the controls (p < 0.01). The significant inhibition effects of curcumin on the proliferation and the growth of human OSCC are observed both in vitro and in vivo. No significant body weight change (i.e. within 20%) was observed in all SAS/luc-bearing mice with or without curcumin treatment. This SAS/luc human OSCC bearing animal model combined with multimodalities of molecular imaging permits a sensitive and non-invasive approach to evaluate the therapeutic efficacy in vivo.

Breast cancer is increasing with years in Taiwan because of dietary style, life behavior and several social-physiological factors. According to the record of Bureau of Health Promotion in Taiwan, the incidence of breast cancer is top one, and the mortality of that is top one cancer type in women. Compared with USA, most of breast cancer cases found in Taiwanese women have reached to stage 2 or 3. Current therapeutic strategies for breast cancer include surgery, radiation therapy, chemotherapy, hormone therapy and targeted therapy. However, these methods used for curing the late-stage breast cancer remains rare. Because the metastasis is the major problem of late-stage breast cancer, it is of interest to investigate whether a systemic therapy can reduce the symptoms of cancer. The immunotherapy, particularly an induction of autoimmune system, is probably important for the treatment of late-stage breast cancer. Glycated chitosan (GC) is derived from chitosan, a linear polysaccharide composed of D-glucosamine and N-acetyl-D-glucosamine through β–(1-4) linkage. Several lines of evidence have shown that GC is an immunoadjuvant that can target on primary and metastatic tumors formed in animal and human patients. In our previous data, GC was demonstrated to decrease the motility and invasion of mammalian breast cancer cells in vitro and in vivo. Radiofrequency ablation (RFA) is dependent on a small generator that delivers high frequency alternating electric current directly to burn a tumor lesion. Therefore, the temperature may reach up to above 60 °C. In this study, we used 4T1 mouse breast cancer cell that is the approximately equal to stage 4 of human breast cancer. And triple modality reporter gene (3R) was delivered into the cells using transfected piggyBac, a transposable element for observation of tumor growth and metastasis in vivo. Data showed that growth and metastasis of tumors smaller than 500mm3 were entirely suppressed by RFA-GC combination treatment. Plasma extraction from this group displayed an inhibitory effect on cultured 4T1 cells, suggesting some immunoreactions were triggered and therefore secreted some cytokines. Protein array data indicated that PF-4 may play a key role in GC-RFA caused tumor suppression but the further effects should be investigated. On the other hand, the survival rate of small tumor-bearing mice under RFA-GC treatment was higher than those of GC or RFA treatment only. In conclusion, this study confirmed that radiofrequency ablation combined with GC could trigger an autoimmune response to inhibit tumor metastasis and tumorigenesis. For metastatic cancers, this combination treatment may become the foundation for a feasible cancer treatment modality.

Immunotherapy has been reported to effectively treat various cancers. In addition, scientists are dedicated in finding whether the combination of radiotherapy and immunotherapy can efficiently suppress cancer progression and recurrence. Although radiotherapy has been widely used for breast cancer, better strategies to overcome the latestage breast cancer remains explored. The glycated chitosan (GC), a novel immunological stimulant, was demonstrated to trigger local immune response facilitating the enhancement of radiosensitivity. Our previous study also revealed that the cell mortality and invasive ability were decreased under GC treatment, but the underlying mechanism remains unclear. In this study, we used 4T1-3R-L, a derived murine breast cancer cell line from the spontaneous metastasized liver lesion. We combined ionizing radiation with GC to treat 4T1-3R-L and found the expression of DNA damage-related genes such as gamma-H2AX was more than radiation alone In addition, the cell cycle distribution and colony forming assay showed an increased sub-G1 population and decreased cell survival rate after IR combined GC treatment. Taken together, we sought to elucidate the underlying mechanism by the investigation of DNA damage repair process when IR combined with GC, and to explore another advantage of GC to aid other cancer treatments. Based on our most updated results, the GC treatment is able to effectively increase the radiosensitivity through an immune-responsive signaling transduction, indicating that GC could be a valuable therapeutic strategy for treating against advanced breast cancers.

Background and purpose Cancer stem cells exhibit distinctive cellular metabolism compared with the more differentiated counterparts or normal cells. We aimed to investigate the impact of a novel radionuclide anti-cancer agent 188 Re-Liposome on stemness markers' expression and cellular metabolism in an ovarian cancer model. Material and methods A 2×2 factorial experiment was designed in which factor 1 represented the drug treatment comparing 188 Re-BMEDA, a free form of 188 Re, with 188 Re-Liposome, a nanoparticle-encapsulated form of 188 Re. Factor 2 represented the delivery route, comparing intravenous with intraperitoneal delivery. Results Intraperitoneal delivery of 188 Re-Liposome predominantly killed the CSCs-like cells in tumours and switched metabolism from glycolysis to oxidative phosphorylation. Further, intraperitoneal delivery of 188 Re-Liposome treatment was able to block epithelial-to-mesenchymal transition (EMT) and reactivate p53 function. Collectively, these molecular changes led to a striking tumour-killing effect. Conclusions Radionuclides encapsulated in liposomes may represent a novel treatment for ovarian cancer when delivered intraperitoneally (a type of loco-regional delivery). In the future, this concept may be further extended for the treatment of several relevant cancers that have been proved to be suitable for loco-regional delivery of therapeutic agents, such as colon cancer, gastric cancer, and pancreatic cancer.

Summary Background The treatment of gliomas poses significant clinical challenges due to resistance to chemo and radiation therapy, and treatment side effects. Metronomic photodynamic therapy (mPDT), which involves long treatment time with low fluence rate and multiple or continuous photosensitizer administrations, has potential in treating gliomas without threatening the quality of life and has been demonstrated in rats and rabbits. mPDT in small animals such as mouse is not yet shown due to lack of lightweight illumination device for long periods of time. Methods We presented low fluence rate (3 mW/cm2) and long duration (3.7 h) PDT treatment in a nude mouse model of human glioblastoma by using organic light emitting diode (OLED) with single dose of 5-aminolevulinic acid (ALA) administration as photosensitizer. Tumor volume was measured using bioluminescent imaging and the animal survival time was recorded. Additionally, we have performed limited PDT dosimetric measurements of PpIX fluorescence, tumor oxygenation and hemoglobin concentration in 3 PDT mice. Results For animals with similar pre- and immediate post-light tumor volume, the averaged total survival time of PDT mice is 40.5 ± 9.2 days that are significantly longer than the control mice (26.0 ± 2.0 days). The post-light survival time of PDT mice is 14.3 ± 5.9 days that are marginally longer than the control group (8.0 ± 0.0 days). In the dosimetric measurement, good maintenance of PpIX fluorescence in one PDT mouse has relatively improved survival time, compared with the other two PDT mice (i.e., 24 days versus 16 and 17 days). Conclusions This pilot study demonstrated the feasibility of low-fluence rate and long treatment time of ALA-PDT using OLED without anesthetization of animals. The response of PDT treated animals with similar pre- and post-light tumor volume is encouraging to show a longer survival time than the controls. The dosimetric indices such as photosensitizer fluorescence and tissue oxygenation would help understand the possible treatment barriers for further improvement of treatment plans.

The actin-depolymerizing factor (ADF)/cofilin protein family has been reported to be associated with ischemia-induced renal disorders. We examine whether cofilin-1 is associated with acute kidney injury (AKI) using human urine samples. We exploited a 96-well based high-throughput biosensor that uses gold nanoparticles and a sandwich immunoassay to detect the urine cofilin-1 level of AKI patients. The mean urine cofilin-1 level of the AKI patients (n=37 from 47 cases analyzed) was twofold higher than that of healthy adults (n=21 from 29 cases analyzed). The receiver operating characteristic (ROC) curve showed that cofilin-1 was acceptable for discriminating AKI patients from healthy adults. However, an increase of the sample size is required to conclude the importance of urine cofilin-1 on AKI diagnosis, and the high-throughput ultrasensitive biosensor used in this study would greatly accelerate the measurement of urine cofilin-1 in an increased sample size.

Securin overexpression correlates with poor prognosis in various tumours. We have previously shown that securin depletion promotes radiation-induced senescence and enhances radiosensitivity in human cancer cells. However, the underlying molecular mechanisms and the paracrine effects remain unknown. In this study, we showed that radiation induced senescence in securin-deficient human breast cancer cells involving the ATM/Chk2 and p38 pathways. Conditioned medium (CM) from senescent cells promoted the invasion and migration of non-irradiated cancer and endothelial cells. Cytokine assay analysis showed the up-regulation of various senescence-associated secretory phenotypes (SASPs). The IL-6/STAT3 signalling loop and platelet-derived growth factor-BB (PDGF-BB)/PDGF receptor (PDGFR) pathway were important for CM-induced cell migration and invasion. Furthermore, CM promoted angiogenesis in the chicken chorioallantoic membrane though the induction of IL-6/STAT3- and PDGF-BB/PDGFR-dependent endothelial cell invasion. Taken together, our results provide the molecular mechanisms for radiation-induced senescence in securin-deficient human breast cancer cells and for the SASP responses.

The actin depolymerizing factor (ADF)/cofilin protein family has been reported to be associated with ischemia induced renal disorders. Here we examine if cofilin-1 is associated with acute kidney injury (AKI). We exploited a 96-well based fiber-optic biosensor that uses conjugated gold nanoparticles and a sandwich immunoassay to detect the urine cofilin-1 level of AKI patients. The mean urine cofilin-1 level of the AKI patients was two-fold higher than that of healthy adults. The receiver operating characteristic (ROC) curve showed that cofilin-1 is a potential biomarker for discriminating AKI patients from healthy adults for intensive care patients.

Glioblastoma multiforme (GBM) is the most malignant brain tumor with the characteristics of highly infiltrative growth and recurrent rate. In this study, we used animal imaging and molecular expressive profiles to investigate the characteristics of the primary tumor (GBM-3) cells and recurrent tumor (S1R1) cells from different GBM patients.Bioluminescent imaging and 3T magnetic resonance imaging (MRI) were used for assessing the orthotopical tumor development of GBM cells harboring a polycistronic reporter gene system. Western blot analysis and quantitative polymerase chain reaction were used to compare the molecular expressive profiles of two types of GBM cells.S1R1 cells exhibited apparent invasive ability compared to GBM-3 cells using in vitro invasion assay. In vivo bioluminescent imaging showed that intracranial tumors are formed by both types of GBM cells, but the bioluminescent signal was also detected in the lumbar region at late-stage tumor formed by S1R1 cells. The MRI showed that intracranial tumors formed by S1R1 cells were highly infiltrative compared to that formed by GBM-3 cells. Additionally, these two GBM types expressed different patterns of molecules associated with tumor development. Moreover, the suppressive effects of interleukine-23 (IL-23) on xenograft tumors formed by both GBM types were detected using bioluminescent imaging.The current data suggest that the in vivo growth behaviors and therapeutic responses of the primary and recurrent human GBMs were comparable using the reporter gene imaging, and different molecular expressive profiles exist between these two GBM types.

Vascular invasion into the normally avascular articular surface is a hallmark of advanced osteoarthritis (OA). In this study, we demonstrated that the expression of tissue inhibitor of metalloproteinases-2 (TIMP2), an anti-angiogenic factor, was present at high levels in normal articular chondrocytes, and was drastically decreased shortly after destabilization of the medial meniscus (DMM). We also investigated the anti-angiogenic properties of TIMP2 via knockout. We hypothesized that the loss of TIMP2 could accelerate osteoarthritis development via promotion of angiogenesis. Loss of TIMP2 led to increased periarticular vascular formation 1 month post DMM, compared to wild-type mice, and did so without altering the expression pattern of matrix metalloproteinases and vascular endothelial growth factors. The increased vascularization eventually resulted in a severe degeneration of the articular surface by 4 months post DMM. Our findings suggest that reduction of TIMP2 levels and increased angiogenesis are possible primary events in OA progression. Inhibiting or delaying angiogenesis by TIMP2 expression or other anti-angiogenic therapies could improve OA prevention and treatment.

Prostate-specific antigen (PSA) has been reported to be a potential biomarker of breast cancer. Serum PSA of normal women is around 1 pg/mL, which is usually undetectable by current assay methods; thus an ultrasensitive measurement of PSA expression in women's serum is necessary to distinguish normal from malignant breast diseases. To enhance the sensitivity of conventional immunoassay technology for the detection of PSA in sera, we adopted a localized surface plasmon coupled fluorescence fiber-optic biosensor, which combines a sandwich immunoassay with the localized surface plasmon technique. The concentration of total PSA (t-PSA) (from 0.1 to 1000 pg/mL) in phosphate-buffered saline solution and the normalized fluorescence signal exhibit a linear relationship where the correlation coefficient is 0.9574. In addition, the concentration of additional t-PSA in 10-fold-diluted healthly women's serum across a similar range was measured. The correlation coefficient for this measurement is 0.9142. In clinical serum samples, moreover, the experimental results of t-PSA detection show that both the mean value and median of normalized fluorescence signals in the breast cancer group (155.2 and 145.7, respectively) are higher than those in the noncancer group (46.6 and 37.1, respectively). We also examined the receiver operating characteristic curve for t-PSA, and the area under the curve (AUC) is estimated to be 0.9063, the AUC being used to measure the performance of a test to correctly identify diseased and nondiseased subjects.

Arsenic exerts its cytotoxicity via the generation of reactive oxygen species and inhibition of DNA repair. How arsenic disturbs oxidative DNA damage repair is, however, unclear. We found that arsenic trioxide (ATO), like ultraviolet (UV) irradiation, induced the expression of xeroderma pigmentosum group C (XPC) but not of xeroderma pigmentosum A in a human glioma cell line, U87. To explore the role of XPC in the toxic effects of ATO, small interfering RNA was used to silence XPC (siXPC) in U87 cells. siXPC cells were more susceptible to UV irradiation and ATO-induced cell death than control cells. Increased siXPC cell death induced by ATO was accompanied by increased senescence and autophagy. Because increased DNA strand breaks in siXPC cells were observed only when cells were concomitantly treated with ATO and DNA repair inhibitors, XPC silencing apparently did not interfere with repair of ATO-induced DNA damage. Although intracellular ROS levels were not significantly enhanced in siXPC cells, ATO treatment did result in increased 8-hydroxy-2'-deoxyguanosine and hyperoxidized peroxiredoxin. Enhanced superoxide production and autophagy by ATO in siXPC cells were suppressed by co-incubation with N-acetylcysteine (NAC). Furthermore, XPC silencing caused decreased glutathione levels and increased catalase and Mn-superoxide dismutase activities. Increased catalase activity in siXPC cells was suppressed by ATO treatment. XPC silencing also enhanced reporter activity of activator protein-1, whereas enhanced activity was suppressed by NAC. Taken together, our results indicate that XPC silencing causes increased ATO susceptibility by disturbing redox homeostasis rather than reducing DNA repair.

To investigate the risk association and compare the onset age of hepatocellular carcinoma (HCC) patients in Taiwan with different genotypes of MDM2-SNP309.We analyzed MDM2-SNP309 genotypes from 58 patients with HCC and 138 cancer-free healthy controls consecutively. Genotyping of MDM2-SNP309 was conducted by restriction fragment length polymorphism assay.The proportion of homozygous MDM2-SNP309 genotype (G/G) in cases and cancer-free healthy controls was similar (17.2% vs 16.7%). Multivariate analysis showed that the risk of G/G genotype of MDM2-SNP309 vs wild-type T/T genotype in patients with HCC was not significant (OR = 1.265, 95% CI = 0.074-21.77) after adjustment for sex, hepatitis B or C virus infection, age, and cardiovascular disease/diabetes. Nevertheless, there was a trend that GG genotype of MDM2-SNP309 might increase the risk in HCC patients infected with hepatitis virus (OR = 2.568, 95% CI = 0.054-121.69). Besides, the homozygous MDM2-SNP309 genotype did not exhibit a significantly earlier age of onset for HCC.Current data suggest that the association between MDM2-SNP309 GG genotype and HCC is not significant, while the risk may be enhanced in patients infected by hepatitis virus in Taiwan.

Oxaliplatin, a chemotherapeutic drug, induces DNA double-strand breaks (DSBs) and apoptosis in colorectal cancer cells. It has been shown that gamma-H2AX acts as a marker of DSBs. However, the molecular events associated with oxaliplatin-mediated cell cycle arrest and cell death remain unclear. In this study, we investigated the roles of p53 and gamma-H2AX following oxaliplatin treatment, as they are important effector proteins for apoptosis and DSB repair, respectively. Both phosphorylated-p53 (Ser-15) and gamma-H2AX were up-regulated and accumulated in the nuclei of p53-wild type human colorectal cancer HCT116 cells after exposure to oxaliplatin. Concomitantly, oxaliplatin-induced G2/M arrest was associated with a reduction in both cyclin B1 expression and phosphorylated-CDC2 (Thr-161). Release of G2/M arrest by caffeine was accompanied by a decrease in the levels of p53/p21; however, gamma-H2AX levels were unchanged. Furthermore, inhibition of p53 phosphorylation by pifithrin-alpha was sufficient to reduce the oxaliplatin-induced up-regulation of gamma-H2AX and apoptosis. Oxaliplatin-induced gamma-H2AX via a p53-independent pathway but did not cause caspase-3 activation in p53-null HCT116 cells. Interestingly, no changes were observed in the H2AX gene knockdown with regards to oxaliplatin-induced G2/M arrest in p53-wild type and S phase arrest in p53-null HCT116 cells. Taken together, these data indicate that a molecular pathway involving p53, gamma-H2AX and cell cycle arrest plays a pivotal role in the cellular response to oxaliplatin.

Background It has been suggested that the single nucleotide polymorphism 309 (SNP309, T -> G) in the promoter region of the MDM2 gene is important for tumor development; however, with regards to breast cancer, inconsistent associations have been reported worldwide. It is speculated that these conflicting results may have arisen due to different patient subgroups and ethnicities studied. For the first time, this study explores the effect of the MDM2 SNP309 genotype on Taiwanese breast cancer patients. Methods Genomic DNA was obtained from the whole blood of 124 breast cancer patients and 97 cancer-free healthy women living in Taiwan. MDM2 SNP309 genotyping was carried out by restriction fragment length polymorphism (RFLP) assay. The multivariate logistic regression and the Kaplan-Meier method were used for analyzing the risk association and significance of age at diagnosis among different MDM2 SNP309 genotypes, respectively. Results Compared to the TT genotype, an increased risk association with breast cancer was apparent for the GG genotype (OR = 3.05, 95% CI = 1.04 to 8.95), and for the TG genotype (OR = 2.12, 95% CI = 0.90 to 5.00) after adjusting for age, cardiovascular disease/diabetes, oral contraceptive usage, and body mass index, which exhibits significant difference between cases and controls. Furthermore, the average ages at diagnosis for breast cancer patients were 53.6, 52 and 47 years for those harboring TT, TG and GG genotypes, respectively. A significant difference in median age of onset for breast cancer between GG and TT+TG genotypes was obtained by the log-rank test (p = 0.0067). Conclusion Findings based on the current sample size suggest that the MDM2 SNP309 GG genotype may be associated with both the risk of breast cancer and an earlier age of onset in Taiwanese women.

Glioblastoma multiforme (GBM) is classified the fourth grade of human glioma that indicates the most malignant brain tumor with poor five-year survival (5%). Accumulated evidence showed that GBM cells were resistant to various therapeutic strategies. Recently, use of arsenic trioxide (ATO) to induce apoptosis and to increase the radiosensitivity was reported for the benefit in treating GBMs. However, the responsible signaling cascades are still remain investigation. MicroRNA, a category of RNA interference, regulates its downstream genes post transcriptionally by binding to the 3′untraslated region (UTR) of its targets. In this study, we used S1 and S1R1 GBM cells which were derived from the primary and the recurrent lesion respectively. Firstly, we identified that an oncogenic microRNA, miR-182, was down-regulated after the treatment of ATO in both GBM cells. In addition, one of the miR-182 targeted coding genes, Sestrin 2 (SESN2), plays an important role in relieving intracellular oxidative stress and participates in TP53 tumor suppressive pathway. Use of luciferase-based reporter assay confirmed that miR-182 directly bound to SESN2 3′UTR and interrupted the further translation. Intriguingly, the basal level of miR-182 in the primary S1 GBM was significantly lower than the recurrent S1R1 GBM, supporting the oncogenic evidence in the previous studies. The counteracted SESN2 expression was also determined by real-time qPCR and western blot. We then hypothesized that ATO may retarded the growth of GBM through a miR-182-SESN2 related regulatory axis. Overexpression of miR-182 in S1 GBM resulted in a decrease of SESN2 and insensitive to ATO treatment. On the opposite, inhibition of miR-182 in S1R1 GBM dramatically retarded the growth rate and sensitized the cells to ATO. Moreover, pretreatment of an antioxidant, N-acetyl-cysteine (NAC), rescued the miR-182 suppression, suggesting that ATO-induced oxidative stress may be dominant in this responsive axis. Concordant expression of miR-182/96/182 cassette was revealed, indicating the transcriptional regulation was unveiled. Further investigation on the detailed machinery still remain elucidating. Based on our findings, we displayed that ATO-induced oxidative stress triggered a tumor suppressive response through a miR-182-SESN2 dependent machinery. Citation Format: Liang-Ting Lin, Shih-Hwa Chiou, Yi-Jang Lee. Study of the tumor suppressive machinery of arsenic trioxide-induced glioblastoma multiforme inhibition via microRNA-182-Sestrin2 regulatory circuit. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 3548. doi:10.1158/1538-7445.AM2014-3548

Stimulation of the host immune system is crucial in cancer treatment. In particular, nonspecific immunotherapies, when combined with other traditional therapies such as radiation and chemotherapy, may induce immunity against primary and metastatic tumors. In this study, we demonstrate that a novel, non-toxic immunoadjuvant, glycated chitosan (GC), decreases the motility and invasion of mammalian breast cancer cells in vitro and in vivo. Lung metastatic ratios were reduced in 4T1 tumor-bearing mice when intratumoral GC injection was combined with local high-intensity focused ultrasound (HIFU) treatment. We postulate that this treatment modality stimulates the host immune system to combat cancer cells, as macrophage accumulation in tumor lesions was detected after GC-HIFU treatment. In addition, plasma collected from GC-HIFU-treated tumor-bearing mice exhibited tumor-specific cytotoxicity. We also investigated the effect of GC on epithelial-mesenchymal transition-related markers. Our results showed that GC decreased the expression of Twist-1 and Slug, proto-oncogenes commonly implicated in metastasis. Epithelial-cadherin, which is regulated by these genes, was also upregulated. Taken together, our current data suggest that GC alone can reduce cancer cell motility and invasion, whereas GC-HIFU treatment can induce immune responses to suppress tumor metastasis in vivo.

The sublethal dose radiation may induce cellular senescence and promote secondary maligancy during radiotherapy. However, the molecular mechanisms are unclear. It has been reported that a variety of early response oncogenes can be up-regulated by the low dose radiation. Because oncogene-induced senescence (OIS) has been considered important for tumor development, we are interested in investigating whether the sublethal dose radiation also raises OIS to affect the malignancy. To this end, human diploid fibroblasts WI-38 cells and human non-small lung cancer H1299 cells were exposed to less than 2Gy of X-rays delivered by the RS2000 X-rays machine. Both cell types exhibited senescent phenotypes within a dose-dependent manner using the senescence-associated β-galactosidase (SA-β-gal) staining. Subsequently, we investigated the expression of c-Myc and c-Ras oncogenes, and the results showed that sublethal dose radiation could induce c-Myc, but not c-Ras, in both transcriptional and translational levels. Additionally, up-regulated c-Myc exhibited transcriptional activity as demonstrated by the promoter-based reporter gene assys. Although the sublethal dose radiation caused cellular senescence and growth delay in exposed cells, the collected culture medium could increase the motility of non-irradiated H1299 cancer cells using the wound healing assay. Interestingly, the culture medium obtained from irradiated H1299 cancer cells caused higher motility in non-irradiated cells than that from irradiated WI-38 fibroblasts. Furthermore, the sublethal dose radiation induced senescent phenotype was suppressed in cells treated with siRNA against c-Myc. Meanwhile, the motility of non-irradiated cells was not increased by the cultured medium obtained from irradiated c-Myc silenced cells. Taken together, the current data suggest that the sublethal dose radiation causes a c-Myc oncogene induced senescence, and this event may promote the bystandard effects that influence the motility of non-irradiated cancer cells. Citation Format: Chia-Chien Lo, Yen-Ting Chou, Su-Jun Chiu, Jeng-Jung Hwang, Yi-Jang Lee. The sublethal dose radiation induces cellular senescence and potent bystander effects through c-Myc oncogene. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 440. doi:10.1158/1538-7445.AM2013-440 Note: This abstract was not presented at the AACR Annual Meeting 2013 because the presenter was unable to attend.

CD133 (Prominin-1) have been reported as one of CNS cancer stem cell markers, and is used for isolating cancer stem cells via fluorescence-activating cell sorting. However, more and more new evidence showed that CD133 cannot totally indicate to cancer stem cells, and the role of CD133 plays in glioblastoma still remains controversial. Here, we tend to use multiple imaging modalities to investigate CD133-positive and CD133-negative cells on tumorigenesis and recurrence in vivo. We sorted patient tumor-derived GBM cells by FACS with CD133-PE staining, and delivered multicistronic reporter system into each group of cells by lentivirus. The established cells stably expressed green fluorescent protein, firefly luciferase and thymidine kinase, and each of them was assayed in vitro. GFP expression was used for collecting cells with better reporter efficiency. Our in vitro results showed that CD133-positive cells revealed shorter doubling time and better transgene expression than CD133-negative cells. Furthermore, both groups of CD133 expression cells were xenografted orthotropically into left brain of NOD/SCID mice, and the tumorigenesis phenomenon were evaluated by magnetic resonance imaging and bioluminescence. Tumor formation was observed in both groups, suggested that CD133 may not be the key role in tumorigenesis of glioblastoma. Moreover, to demonstrate the relationship between cancer recurrence and cancer stem cells, we also treated the xenografted mice with ganciclovir to generate cytotoxicity by tk gene for 2 weeks, and in vivo imaging was recorded for upcoming 2 weeks. For future work, we plan to figure out whether the CD133 takes the most responsibility in tumor recurrence, and look forward to the other stemness-related markers such as Sox2, that may also provide a novel approach in cancer prognosis. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 101st Annual Meeting of the American Association for Cancer Research; 2010 Apr 17-21; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2010;70(8 Suppl):Abstract nr 3354.

Background 1-{4-[Bis(2-chloroethyl)amino]phenyl}-3-[2-methyl-5-(4-methylacridin-9-ylamino)phenyl]urea (BO-1051) is an N-mustard DNA alkylating agent reported to exhibit antitumor activity. Here we further investigate the effects of this compound on radiation responses of human gliomas, which are notorious for the high resistance to radiotherapy. Methods The clonogenic assay was used to determine the IC50 and radiosensitivity of human glioma cell lines (U87MG, U251MG and GBM-3) following BO-1051. DNA histogram and propidium iodide-Annexin V staining were used to determine the cell cycle distribution and the apoptosis, respectively. DNA damage and repair state were determined by γ-H2AX foci, and mitotic catastrophe was measure using nuclear fragmentation. Xenograft tumors were measured with a caliper, and the survival rate was determined using Kaplan-Meier method. Results BO-1051 inhibited growth of human gliomas in a dose- and time-dependent manner. Using the dosage at IC50, BO-1051 significantly enhanced radiosensitivity to different extents [The sensitizer enhancement ratio was between 1.24 and 1.50 at 10% of survival fraction]. The radiosensitive G2/M population was raised by BO-1051, whereas apoptosis and mitotic catastrophe were not affected. γ-H2AX foci was greatly increased and sustained by combined BO-1051 and γ-rays, suggested that DNA damage or repair capacity was impaired during treatment. In vivo studies further demonstrated that BO-1051 enhanced the radiotherapeutic effects on GBM-3-beared xenograft tumors, by which the sensitizer enhancement ratio was 1.97. The survival rate of treated mice was also increased accordingly. Conclusions These results indicate that BO-1051 can effectively enhance glioma cell radiosensitivity in vitro and in vivo. It suggests that BO-1051 is a potent radiosensitizer for treating human glioma cells.