Should Patients with Renal Cell Carcinoma and Pathological Nodal Invasion Be Classified As Having Stage IV Disease?

BACKGROUND

Lymph node invasion is associated with poor outcome in patients with renal cell carcinoma (RCC).

PATIENTS AND METHODS

Patients with RCC within a single center from 2001 to 2018 were retrospectively obtained from the Chang Gung Research Database. Patient gender, physical status, Charlson Comorbidity Index, tumor side, histology, age at diagnosis, and body mass index (BMI) were compared. The overall survival (OS) and cancer-specific survival (CSS) of each group were estimated using the Kaplan-Meier method. Log-rank tests were used to compare between the subgroups.

RESULTS AND CONCLUSIONS

A total of 335 patients were enrolled, of whom 76 had pT3N0M0, 29 had pT1-3N1M0, 104 had T1-4N0M1, and 126 had T1-4N1M1 disease. Significant OS difference was noted between pT3N0M0 and pT1-3N1M0 groups with 12.08 years [95% confidence interval (CI), 8.33-15.84] versus 2.58 years (95% CI, 1.32-3.85), respectively (P < 0.005). No significant difference was observed in OS between pT1-3N1M0 and T1-4N0M1 groups with 2.58 years (95% CI, 1.32-3.85) versus 2.50 years (95% CI, 1.85-3.15, P = 0.72). The OS of N1M1 group was worse than that of N0M1 group with 1.00 year (95% CI, 0.74-1.26) versus 2.50 years (95% CI, 1.85-3.15, P < 0.05). Similar results were also observed in CSS. In summary, we claim that RCC with lymph node (LN) invasion should be reclassified as stage IV disease in terms of survival outcome.

Urinary MicroRNA Sensing Using Electrochemical Biosensor to Evaluate Colorectal Cancer Progression

Research in cancer diagnostics has recently established its footing and significance in the biosensor sphere, emphasizing the idea of a unique probe design used as a sensor and actuator, to identify the presence of protein, DNA, RNA, or miRNA. The fluorescein isothiocyanate (FITC) probe and biotinylated probe are designed for a two-pronged approach to the detection of the urinary miR-21 and miR-141, both of which have demonstrated significance in the development and progression of colorectal cancer, a leading cause of mortality and morbidity. The remainder of the apparatus is composed of a modified screen-printed carbon electrode (SPCE), to which the probes adhere, that transduces signals via the redox reaction between H2O2 and HRP, measured with chronoamperometry and cyclic voltammetry. The precise nature of our ultra-non-invasive biosensor makes for a highly sensitive and practical cancer detector, concluded by the significance when establishing disease presence (miR-21 p-value = 0.0176, miR-141 p-value = 0.0032), disease follow-up (miR-21 p-value = 0.00154, miR141 p-value < 0.0005), and even disease severity. This article hopes to emphasize the potential of an additional clinical tool for the management of colorectal cancer.

Glucose/Glutathione Co-triggered Tumor Hypoxia Relief and Chemodynamic Therapy to Enhance Photothermal Therapy in Bladder Cancer

Photothermal therapy (PTT) is a potential treatment for cancer that makes use of near-infrared (NIR) laser irradiation and is expected to assist traditional anti-cancer drug therapies; however, the therapeutic efficacy of PTT is restricted by thermal resistance due to the overexpression of heat shock proteins and insufficient penetration depth of lasers. Thus, PTT needs to be combined with additional therapeutic methods to obtain the optimal therapeutic efficacy for cancer. Herein, a multifunctional therapeutic platform combining PTT with glucose-triggered chemodynamic therapy (CDT) and glutathione (GSH)-triggered hypoxia relief was developed via GOx@MBSA-PPy-MnO₂ NPs (GOx for glucose oxidase, M for Fe₃O₄, BSA for bovine serum albumin, and PPy for polypyrrole). GOx@MBSA-PPy-MnO₂ NPs have excellent photothermal efficiency and can release Mn²⁺, which catalyzes the transformation of H₂O₂ into hydroxyl radicals (·OH) and O₂ via a Fenton-like reaction, effectively destroying cancer cells and relieving tumor hypoxia. Meanwhile, a high content of H₂O₂ was produced via GOx catalysis of glucose, further enhancing the CDT efficiency. In addition, in vitro and in vivo experiments showed that the inhibition of cancer cell proliferation and effective inhibition of tumors could be caused by the combined PTT/glucose-triggered CDT effects and hypoxia relief of the GOx@MBSA-PPy-MnO₂ NPs. Overall, this work provides evidence of a synergistic therapy that remarkably improves therapeutic efficacy and significantly prolongs the lifetime of mice compared with controls.

Gain of TPPP as a predictor of progression in patients with bladder cancer

The present study investigated the role of tubulin polymerization promoting protein (TPPP) in the regulation of bladder cancer (BC) cell proliferation and migration, in addition to the association between TPPP gene copy number amplification and clinicopathological characteristics of BC. TPPP gene amplification was measured in human BC epithelial cells and samples obtained from 52 patients with BC via fluorescence in situ hybridization. TPPP gain was defined as mean TPPP copy number >2.2 per nucleus (cutoff). The neutrophil-to-lymphocyte ratio (NLR) was also obtained from the preoperative data of the patients. For in vitro assays, BC cell lines were transfected with either TPPP small interfering RNAs or scrambled control, following which cell proliferation and migration were determined using Cell Counting Kit-8 and Transwell migration assays, respectively. The percentage of cells with TPPP copy number amplification in the four BC epithelial cell lines (MGH-U1, -U1R, -U3, -U4) examined (86.0-100.0%) was found to be higher compared with that in the normal human uroepithelial cell lines (3.0 and 9.0%). Patients were divided into one- (1.9%), two- (55.8%), three- (7.7%), four- (26.9%) and five-copy (7.7%) types. Results calculated using Fisher's exact test indicated that the gain of TPPP in patients with BC associated significantly with age (P<0.05), advanced histological grade (P<0.001), tumor stage (P<0.05), histological type (P<0.001) and NLR (P<0.05). In MGH-U1R and MGH-U4 cells, cell proliferation and migration were revealed to be significantly lower following TPPP knockdown compared with those in cells transfected with the scrambled control. In conclusion, findings from the present study suggest that TPPP is important for cell proliferation, cell migration and BC progression, such that TPPP copy number assessment would be advised for preoperative urine cytology for urothelial neoplasia diagnosis.

An Effective SARS-CoV-2 Electrochemical Biosensor with Modifiable Dual Probes Using a Modified Screen-Printed Carbon Electrode

Due to the severe acute respiratory syndrome coronavirus (SARS-CoV-2, also called coronavirus disease 2019 (COVID-19)) pandemic starting in early 2020, all social activities ceased in order to combat its high transmission rate. Since vaccination combats one aspect for halting the spread of the virus, the biosensor community has looked at another aspect of reducing the burden of the COVID-19 pandemic on society by developing biosensors that incorporate point-of-care (POC) testing and the rapid identification of those affected in order to deploy appropriate measures. In this study, we aim first to propose a screen-printed carbon electrode (SPCE)-based electrochemical biosensor that meets the ASSURED criteria (i.e., affordable, sensitive, specific, user-friendly, rapid, equipment-free, and deliverable) for POC testing, but more importantly, we describe the novelty of our biosensor’s modifiability that uses custom dual probes made from target nucleic acid sequences. Additionally, regarding the sensitivity of the biosensor, the lowest sample concentration was 10 pM (p = 0.0257) without amplification, which might challenge the traditional technique of reverse transcriptase-polymerase chain reaction (RT-PCR). The purpose of this study is to develop a means of diagnostics for the current pandemic as well as to provide an established POC platform for future epidemics.

Low PTEN expression and overexpression of phosphorylated AktSer473 and AktThr308 are associated with poor overall survival in upper tract urothelial carcinoma

The PI3K/Akt signaling pathway serves an essential role in various cellular processes, including cell growth, survival, cell motility, angiogenesis and cell metabolism. Loss of PTEN expression and hyperactivation of Akt can result in tumorigenesis. Previous studies observed expression of the Akt protein and absence of the PTEN protein in bladder cancer and non-small cell lung carcinoma tissues. The aim of the present study was to evaluate the expression status and prognostic value of PTEN and the PI3K/Akt signaling pathway in Taiwanese patients with upper tract urothelial carcinoma (UTUC). Archival formalin-fixed, paraffin-embedded (FFPE) tissues from 65 UTUC cases were stained via immunohistochemistry for PTEN, phosphorylated (p)Akt serine (Ser)⁴⁷³ and pAkt threonine (Thr)³⁰⁸. The expression levels of each protein were significantly correlated with clinicopathological parameters. PTEN, pAkt^Ser473 and pAkt^Thr308 protein expression levels were higher in adjacent normal tissues compared with those in tumor tissues. Cytoplasmic PTEN protein expression levels were lower in high-stage tumors compared with those in low-stage tumors, and nuclear and cytoplasmic pAkt^Thr308 protein expression levels were higher in high-grade tumors compared with those in low-grade tumors. Univariate analysis showed that high pathological tumor stage (pT2-4) [P=0.01; hazard ratio (HR)=3.40; 95% confidence interval (CI), 1.34-8.60], metastatic status (P=0.003; HR=3.55, 95% CI, 1.55-8.11), low cytoplasmic PTEN protein expression levels (P=0.016; HR=3.14; 95% CI, 1.24-7.95) and high cytoplasmic pAkt^Ser473 protein expression levels (P=0.019, HR=2.71, 95% CI, 1.18-6.21) were predictive of poor overall survival. However, only metastatic status (P=0.031; HR=2.73; 95% CI, 1.10-6.78), low cytoplasmic PTEN protein expression levels (P=0.017; HR=3.29; 95% CI, 1.24-8.73) and high cytoplasmic pAkt^Ser473 protein expression levels (P=0.027; HR=2.64; 95% CI, 1.12-6.23) remained significant in the multivariate analysis. Kaplan-Meier survival analysis showed that high T stage, metastasis, low expression levels of cytoplasmic PTEN protein and high expression levels of cytoplasmic pAkt^Ser473 protein were significantly associated with poor survival (P=0.006, 0.001, 0.011 and 0.014, respectively). Co-expression of PTEN^low/pAkt^Ser473/high and pAkt^Thr308/high phenotypes was associated with a less favorable overall survival (P=0.001). Overall, the present findings demonstrated that low expression levels of PTEN and high expression levels of pAkt^Ser473 and pAkt^Thr308 were predictors for poor overall survival in patients with UTUC.

Over-expression of TNNI3K is associated with early-stage carcinogenesis of cholangiocarcinoma

Cholangiocarcinoma (CCA) is a devastating disease with very poor prognosis due to late diagnosis and resistance to traditional chemotherapies and radiotherapies. Herein, thioacetamide (TAA)-induced rat CCA model and CGCCA cell line were used; we aim to study the cytogenetic features during tumoral development of CCA and uncover the mystery regarding carcinogenesis of CCA. The Array comparative genomic hybridization analysis, in silico method, gene knockdown, Western blot, cell count proliferation assay, clonogenecity assay, and IHC staining were applied in this study. Array comparative genomic hybridization analysis was performed on all different TAA-induced phases of rat tissues to reveal the certain pattern, +2q45, +Xq22, -12p12, have been identified for the tumor early stage, where involve the gene TNNI3K. In addition, 16 genes and 3 loci were associated with rapid tumor progression; JAK-STAT signaling pathway was highly correlated to late stage of CCA. In silico database was used to observe TNNI3K was highly express at tumor part compared with normal adjacent tissue in CCA patients from TCGA dataset. Furthermore, the growth of TNNI3K-knockdown SNU308 and HuCCT1 cells decreased when compared with cells transfected with an empty vector cell demonstrated by proliferation and colonogenecity assay. Besides, over expression of TNNI3K was especially confirmed on human CCA tumors and compared with the intrahepatic duct stone bile duct tissues and normal bile duct tissues (P < 0.001). Our findings might uncover the mystery regarding carcinogenesis of CCA, and provide the potential genetic mechanism to the clinicians some ideas for the patients' treatment.

EPA significantly improves anti-EGFR targeted therapy by regulating miR-378 expression in colorectal cancer

It is known that colorectal cancer (CRC) cells containing mutations of the genes KRAS and BRAF are predominate mechanisms causing resistance to epidermal growth factor receptor (EGFR) inhibitors, and commonly exhibit a lower expression of microRNA-378 (miR-378) when compared with the wild type. In the present study, the aim was to determine the possible mechanism which associates miR-378 with the mitogen-activated protein kinase pathway, and to determine the efficiency of eicosapentaenoic acid ethyl ester (EPA) in its ability to restore sensitivity towards cetuximab, an EGFR inhibitor. The results demonstrated that a combined treatment of 40 µM EPA with 0.2 µM cetuximab can significantly suppress the cell growth in KRAS-mutant and control wild-type cells. Furthermore, the higher phosphorylated protein level of extracellular-signal-regulated kinase 1/2 was notable in KRAS EPA-treated cells (P=0.006-0.047) and resulted in significantly increased cell death; however, inconsistent results were indicated in EPA-treated BRAF-mutant cells, compared with the original cells (without treatment). KRAS-mutant and wild-type Caco-2 cells treated with EPA exhibited increased cetuximab response rates, but these response rates were reduced in the BRAF-mutant cells. In conclusion, upregulation of miR-378 induced by EPA may result in the significant restoration of sensitivity to cetuximab in the KRAS-mutant cells. The present data will contribute to a notable potential therapeutic solution for future clinical CRC treatments.

Loss of tumor suppressor KDM6A amplifies PRC2-regulated transcriptional repression in bladder cancer and can be targeted through inhibition of EZH2

Trithorax-like group complex containing KDM6A acts antagonistically to Polycomb-repressive complex 2 (PRC2) containing EZH2 in maintaining the dynamics of the repression and activation of gene expression through H3K27 methylation. In urothelial bladder carcinoma, KDM6A (a H3K27 demethylase) is frequently mutated, but its functional consequences and therapeutic targetability remain unknown. About 70% of KDM6A mutations resulted in a total loss of expression and a consequent loss of demethylase function in this cancer type. Further transcriptome analysis found multiple deregulated pathways, especially PRC2/EZH2, in KDM6A-mutated urothelial bladder carcinoma. Chromatin immunoprecipitation sequencing analysis revealed enrichment of H3K27me3 at specific loci in KDM6A-null cells, including PRC2/EZH2 and their downstream targets. Consequently, we targeted EZH2 (an H3K27 methylase) and demonstrated that KDM6A-null urothelial bladder carcinoma cell lines were sensitive to EZH2 inhibition. Loss- and gain-of-function assays confirmed that cells with loss of KDM6A are vulnerable to EZH2. IGFBP3, a direct KDM6A/EZH2/H3K27me3 target, was up-regulated by EZH2 inhibition and contributed to the observed EZH2-dependent growth suppression in KDM6A-null cell lines. EZH2 inhibition delayed tumor onset in KDM6A-null cells and caused regression of KDM6A-null bladder tumors in both patient-derived and cell line xenograft models. In summary, our study demonstrates that inactivating mutations of KDM6A, which are common in urothelial bladder carcinoma, are potentially targetable by inhibiting EZH2.

Abstract 3984: Increasing microRNA-378 to enhance sensitivity of EGFR inhibitor in colorectal cancer

Colorectal cancer (CRC) is the fourth most frequently diagnosed cancer, more then 40% of patients with CRC have KRAS mutations are resistant to anti-EGFR therapy. Lower expression of microRNA-378 (miR-378) was reported to be associated with CRC contain with KRAS or BRAF mutation when compared with wild type of CRC cells. As known that miR-378 is derived from the 3′-UTR of PGC-1β (Peroxisome proliferator activated receptor gamma coactivator-1β) gene, and expressed abundantly could be stimulated by lauric acid. Therefore, we hypothesized once increase the expression level of miR-378 might restore the sensitivity to anti-EGFR sensitizing of cetuximab in KRAS or BRAF mutated colon cancer cells. Herein, we firstly enhanced expression level of miR-378 in mutants via transfection method, and further treated with cetuximab, hopefully, the mutants re-sensitizing to previously failed therapies could be demonstrated. Seven colon cancer cell lines with confirmed KRAS and BRAF statuses were used in current study. Untreated original cells, cells treated with cetuximab, cells transfected with miR-378, and miR-378 transfected cells combined with cetuximab treatment were included. Cell viabilities were then measured for all, and compared to each other group. Our results showed, after transfected miR-378, although most all of KRAS mutants increased cell viabilities except the BRAF mutated CRC cells; nevertheless, the mutants significantly responsed to cetuximab treatment could be observed when compared to the cells treated with cetuximab only. The results indicated that increased the level of miR-378 combined anti-EGFR drug treatment could lead cell viabilities significantly decreased in either BRAF mutants or 50% of KRAS mutated cells. Obviously, re-sensitized to anti-EGFR drug was coming off following transfected with miR-378 in mutated cells. Based on above findings, we then further tried to use lauric acid (C12:0) to enhance the expression level of miR-378 in the cancer cells, and hopefully it would benefit to those CRC cases who ever failed to anti-EGFR antibody treatment. The similar results showed once enhancing the expression level of miR-378, and then treated with anti-EGFR antibody, consequentially lower cell survival could be observed. Lower protein expression of ERK 1/2 has been also been observed in lauric acid treated CRC cells. All the results tend to disclose lauric acid might be an element, which could trigger KRAS cells restored sensitivity to anti-EGFR based drug. In conclusion, elevating miR-378 expression level in mutated CRC cells by lauric acid, which could be easily derived from olive oil, would allow drug re-sensitization in both BRAF and 50% of KRAS mutated cells, the cells were all significantly suppressed by cetuximab. The role of miR-378 in modulating anti-EGFR sensitivity is obvious; therefore, it was strongly suggested to be a potentially new strategy for the clinical CRC patients who have failed anti-EGFR drug treatment.

Note: This abstract was not presented at the meeting.

Citation Format: Shih-Chun Bian, Wai-Hung Leung, Yeu-Jye Pang, Yu-Wen Wu, Jing-Jung Chen, Wen-Hui Weng. Increasing microRNA-378 to enhance sensitivity of EGFR inhibitor in colorectal cancer. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 3984. doi:10.1158/1538-7445.AM2015-3984

Abstract 2695: Using eicosapentaenoic acid to improve cetuximab sensitivity in KRAS mutants

It is known that epidermal growth factor receptor (EGFR) inhibitor, cetuximab, does not respond to cells with KRAS or BRAF mutations; therefore, a large proportion (more than 40%) of colorectal cancer patients are unable to receive this type of target therapy, and can only undergo surgical as a way of management. In this study, we aim to provide an alternative therapeutic strategy to KRAS or BRAF mutated neoplasms. Our previous studies have demonstrated that there may be better sensitivity to anti-EGFR antibody therapy in KRAS or BRAF mutants with increasing expression levels of miR-378. As known, miR-378 is embedded within PPARGC1b, which encodes PGC-1β, and could be stimulated by feeding lauric acid in cells. However, lauric acid is a type of saturated fatty acid, and therefore daily intake in humans is no recommended. Consequently, we tried to replace it with eicosapentaenoic acid (EPA or also icosapentaenoic acid), an omega-3 unsaturated fatty acid that is FDA-approved. Following this, we modulated the expression level of miR-378 in KRAS or BRAF mutants by feeding EPA in vitro, and eventually revealed the mechanism of cancer cells remission that currently remains unknown. The western blotting and ELISA assay were performed to analyze the MAPK/ERK pathway and caspase pathway in three cell lines (SW480 and HCT116 with contain KRAS mutants, and HT29 with contain BRAF mutants), including cell lines before and after feeding with 40 μM concentration of EPA. All experiments were then compared to the wild type cells (caco2), the control cell line. The results showed higher expression of miR-378 in all types of mutated cells, except the wild type CRC cells. In addition, lower cancer cell survival rate was observed in cells that were given 0.2 μM of cetuximab treatment, especially in KRAS mutated cells as well as control wild type cells (p = 0.010∼0.013). The total ERK1/2 protein in the KRAS mutant CRC cells and wild type CRC cell showed lower expression levels after receiving 40 μM EPAee for 24 hours (p = 0.022∼0.035). A higher phosphorylated proteins status of ERK1/2 was also seen (p = 0.006∼0.047). However, the opposite result was noted in BRAF mutant cells. In cells further treated with anti-EGFR antibody for 48 hours, cell viability was significantly lowered in KRAS mutant and control wild type cells (p = 0.006∼0.013), but there was no sensitivity of anti-EGFR antibody reaction to the EPA-fed BRAF mutant cell. The data demonstrated with EPA may indeed significantly induce the expression of miR-378, and further restored the sensitivity of anti-EGFR antibody in KRAS mutant cells. In conclusion, KRAS mutant cells may restore sensitivity to cetuximab after up-regulation of the miR-378 induced by EPA. This finding has offered a new alternative therapeutic solution for future patients suffering from KRAS mutated colorectal cancer.

Citation Format: Chih-Wei Chen, Li-Wei Kuo, Yeu-Jye Pang, Wai-Hung Leung, Wen-Hui Weng. Using eicosapentaenoic acid to improve cetuximab sensitivity in KRAS mutants. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 2695. doi:10.1158/1538-7445.AM2015-2695

Mutation signatures implicate aristolochic acid in bladder cancer development

BACKGROUND

Aristolochic acid (AA) is a natural compound found in many plants of the Aristolochia genus, and these plants are widely used in traditional medicines for numerous conditions and for weight loss. Previous work has connected AA-mutagenesis to upper-tract urothelial cell carcinomas and hepatocellular carcinomas. We hypothesize that AA may also contribute to bladder cancer.

METHODS

Here, we investigated the involvement of AA-mutagenesis in bladder cancer by sequencing bladder tumor genomes from two patients with known exposure to AA. After detecting strong mutational signatures of AA exposure in these tumors, we exome-sequenced and analyzed an additional 11 bladder tumors and analyzed publicly available somatic mutation data from a further 336 bladder tumors.

RESULTS

The somatic mutations in the bladder tumors from the two patients with known AA exposure showed overwhelming AA signatures. We also detected evidence of AA exposure in 1 out of 11 bladder tumors from Singapore and in 3 out of 99 bladder tumors from China. In addition, 1 out of 194 bladder tumors from North America showed a pattern of mutations that might have resulted from exposure to an unknown mutagen with a heretofore undescribed pattern of A > T mutations. Besides the signature of AA exposure, the bladder tumors also showed the CpG > TpG and activated-APOBEC signatures, which have been previously reported in bladder cancer.

CONCLUSIONS

This study demonstrates the utility of inferring mutagenic exposures from somatic mutation spectra. Moreover, AA exposure in bladder cancer appears to be more pervasive in the East, where traditional herbal medicine is more widely used. More broadly, our results suggest that AA exposure is more extensive than previously thought both in terms of populations at risk and in terms of types of cancers involved. This appears to be an important public health issue that should be addressed by further investigation and by primary prevention through regulation and education. In addition to opportunities for primary prevention, knowledge of AA exposure would provide opportunities for secondary prevention in the form of intensified screening of patients with known or suspected AA exposure.

Genome-wide gene expression profiling of ischemia-reperfusion injury in rat kidney, intestine and skeletal muscle implicate a common involvement of MAPK signaling pathway

The mechanisms of ischemia‑reperfusion (I/R) injury have not been fully elucidated to date. In order to determine the genetic involvement across different organs during I/R injury, a DNA microarray approach was used to analyze the gene expression profiles of the kidney, intestine, and skeletal muscle in a rat model of I/R injury. Fifteen male Lewis rats were divided randomly into three different organ groups; a sham operation (control group), 60‑min‑ischemia (Is group) only, and 60‑min‑ischemia plus 60‑min‑reperfusion (I/R group), respectively. The target genes were identified by DNA microarray and studied by quantitative polymerase chain reaction (qPCR). By comparing the I/R group with the control group, a 2‑fold upregulation of 467, 172, and 3932 and a 2‑fold downregulation of 437, 416, and 4203 genes were identified in the kidney, small intestine, and skeletal muscle, respectively. Several commonly upregulated genes associated with mitogen‑activated protein kinase (MAPK) pathways, including Jun, Atf3, junB, Fos, Adm and Dusp 1, were differentially expressed in the I/R group. The mRNA expression levels of the target genes were confirmed by qPCR. The present study hypothesized that the MAPK pathway may function in a common pathway of I/R injury and regulate the pathogenesis through activator protein 1. The findings of the present study contributed to the understanding of the molecular pathways associated with I/R injury.

Aberrant expression of the PRAC gene in prostate cancer

Identification of aberrant expression patterns of genes in prostate cancer (PCa) is a key step towards the development of effective therapies. Prostate-specific antigen (PSA) levels are commonly measured for the early detection of PCa, but which itself is still not an ideal biomarker. We analysed the expression patterns of prostate cancer susceptibility candidate (PRAC) in prostate cancer. The PRAC gene is known to be commonly expressed in prostate tissue, rectum and colon. To provide clear insights into the expression patterns of PRAC in PCa, we examined the gene expression by quantitative real-time PCR (qRT-PCR), western blot analysis and immunohistochemistry (IHC). The results showed that PRAC expression levels in androgen‑insensitive cells (DU145 and PC3) are lower than those in androgen-sensitive cell lines (LNCaP, LNCaP-R and CW22R). However, treatment of the LNCaP cell line with androgen and anti-androgen demonstrated that PRAC is expressed in an androgen-independent manner. Further, PRAC expression was restored upon treatment of DU145 and PC3 cells with the methyltransferase inhibitor, 5-aza-2'-deoxycytidine (5-aza-CdR), which indicates the effect of methylation in the control of PRAC expression. In addition, IHC analysis revealed a significantly decreased immunoreactivity of PRAC protein in PCa tissues compared to benign prostatic hyperplasia (BPH) (p<0.0001). Thus, our findings suggest that the pathogenesis of PCa may be due to the expression levels of PRAC protein, and this protein can serve as a potential biomarker for the management of PCa.

cDNA microarray profiling of rat cholangiocarcinoma induced by thioacetamide

Cholangiocarcinoma (CCA) is a malignant neoplasm affecting thousands of individuals worldwide. CCA develops through a multistep process. In the current study, an oral thioacetamide (TAA)‑induced model of rat CCA was established which generates the histological progression of human CCA, particularly the mass‑forming type. Seven male Sprague‑Dawley rats were treated with TAA for 24 weeks to induce CCA. Following the generation of the rat CCA model, whole rat genomic oligo microarray was performed to examine gene expression profiles in CCA and non‑cancerous liver samples. In brief, 10,427 genes were found to be differentially expressed (8,318 upregulated and 3,489 downregulated) in CCA compared with non‑tumor liver tissue. The top 50 genes (upregulated or downregulated) were selected and their functional involvement in various pathways associated with cancer progression was analyzed, including cell proliferation, apoptosis, metabolism and the cell cycle. In addition, increased expression of CLCA3, COL1A2, DCN, GLIPr2 and NID1, and decreased expression of CYP2C7 and SLC10A1 were validated by quantitative real‑time PCR. Immunohistochemical analysis was performed to determine the protein expression levels of GLIPr2 and SLC10A1. The gene expression profiling performed in this study provides a unique opportunity for understanding the carcinogenesis of TAA‑induced CAA. In addition, expression profiling of a number of specific genes is likely to provide important novel biomarkers for the diagnosis of CCA and the development of novel therapeutic strategies for CCA.

Role of TRPV1 and P2X receptors in the activation of lung vagal C-fiber afferents by inhaled cigarette smoke in rats

Inhaled cigarette smoke (CS) triggers airway reflexes that are thought to result from the activation of lung vagal C-fiber afferents (LVCAs) via the action of reactive oxygen species in rats. We investigated the role of transient receptor potential vanilloid 1 (TRPV1) and P2X receptors in LVCA activation. Activities of LVCAs were recorded in anesthetized and artificially ventilated rats. Airway challenge of CS produced a concentration-dependent fiber stimulation. Pretreatment with dimethylthiourea [DMTU; a scavenger of hydroxyl radical (OH)], capsazepine (CPZ; a TRPV1 receptor antagonist) and iso-pyridoxalphosphate-6-azophenyl-2',5'-disulphonate (iso-PPADS; a P2X receptor antagonist) separately reduced the fiber responses by 64, 40 and 44%, respectively, whereas pretreatment with hexamethonium (a nicotinic acetylcholine receptor antagonist) failed to alter the response. A combination of CPZ and iso-PPADS exerted a greater inhibitory effect compared with the effect of either single pretreatment. However, a combination of DMTU, CPZ and iso-PPADS did not further reduce the fiber response compared with the combined effect of CPZ and iso-PPADS. It was concluded that both TRPV1 and P2X receptors, but not nicotinic acetylcholine receptors, participate in the stimulation of LVCAs by inhaled CS, possibly through the action of OH.

Efficient expansion of mesenchymal stem cells from mouse bone marrow under hypoxic conditions

To realize the therapeutic potential of mesenchymal stem cells (MSCs), a large number of high-quality MSCs isolated from different species, such as mouse, were acquired for preclinical animal studies. Surprisingly, isolation and purification of mouse MSCs (mMSCs) is arduous because of the low frequency of MSCs and contamination of haematopoietic cells in culture. We have developed a method based on low density and hypoxic culture to isolate and expand mMSCs from different strains, including BALB/c, C57BL/6J, FVB/N and DBA/2. The cells from all of the strains expanded more rapidly when plated at low density in hypoxic culture compared with normoxic culture. These cells expressed CD44, CD105, CD29 and Sca-1 markers but not CD11b, CD34, CD45 and CD31 markers. Moreover, they were able to differentiate along osteoblastic, adipocytic and chondrocytic lineages. In conclusion, we have developed a robust method for isolation and expansion of mMSCs by combining low-density culture with hypoxic culture.

Phosphorylated T567 ezrin is associated with merlin expression in KIT-mutant gastrointestinal stromal tumors

Membrane-cytoskeleton linker organizer ezrin is a member of the ERM (ezrin-radixin-moesin) protein family. It has been suggested as an important element in the oncogenic process, particularly in conferring a metastatic ability on tumor cells. We hypothesized that the KIT oncogenic form is one of the proteins that modulates expression of the ezrin protein via phosphorylated ezrin at different residues; furthermore, it may interact with the protein merlin, and promoting tumor development via the PI3K or MAPK pathway. In the present study, we observed that differential expression of ezrin was a common feature in gastrointestinal stromal tumors (GISTs). We further demonstrated that cases exhibiting expression of phosphorylated Thr567 in the ezrin protein were associated with immunoactivities of KIT and merlin expression (p=0.039 and 0.013, respectively). In conclusion, GISTs harbor activation of KIT protein may induce phosphorylation of the downstream protein ezrin at certain residues, thereby triggering subsequent signal transduction cascades and driving downstream pathways of tumor progression. However, a larger series of tumor samples should be analyzed in future studies, as well as the identification of phosphorylated sites to determine the role of ezrin in tumor progression thus shedding light on clinical outcomes.

Characterization of a novel rat cholangiocarcinoma cell culture model-CGCCA

AIM: To characterize a culture model of rat CCA cells, which were derived from a transplantable TTA-induced CCA and designated as Chang Gung CCA (CGCCA).

METHODS: The CGCCA cells were cultured at in vitro passage 12 times on a culture dish in DMEM medium. To measure the doubling time, 10³ cells were plated in a 96-well plate containing the growth medium. The cells were harvested 4 to 10 d after seeding, and a standard MTT assay was used to measure the growth. The phenotype of CACCA cell and xenograft was determined by immunohistochemical study. We also determine the chromosomal alterations of CGCCA, G-banding and spectral karyotyping studies were performed. The CGCCA cell line was transplanted into the nude mice for examining its tumorigenicity. 2-Deoxy-2-(¹⁸F)fluoro-D-glucose (FDG) autoradiography was also performed to evaluate the FDG uptake of the tumor xenograft.

RESULTS: The doubling time for the CGCCA cell line was 32 h. After transplantation into nude mice, FDG autoradiography showed that the tumors formed at the cell transplantation site had a latency period of 4-6 wk with high FDG uptake excluding necrosis tissue. Moreover, immunohistochemical staining revealed prominent cytoplasmic expression of c-erb-B2, CK19, c-Met, COX-II, EGFR, MUC4, and a negative expression of K-ras. All data confirmed the phenotypic features of the CGCCA cell line coincide with the xenograft mice tumors, indicating cells containing the tumorigenicity of CCA originated from CCA. In addition, karyotypic banding analysis showed that the diploid (2n) cell status combines with ring and giant rod marker chromosomes in these clones; either both types simultaneously appeared or only one type of marker chromosome in a pair appeared in a cell. The major materials contained in the marker chromosome were primarily identified from chromosome 4.

CONCLUSION: The current CGCCA cell line may be used as a non-K-ras effect CCA model and to obtain information and reveal novel pathways for CCA. Further applications regarding tumor markers or therapeutic targeting of CCA should be addressed accordingly.

Abstract 3881: Genetic alterations in intrahepatic cholangiocarcinoma- revealed by array CGH, SKY and gene expression microarray

Cholangiocarcinoma (CCA) is an adenocarcinoma of the biliary tract, which is considered to be an incurable and rapidly lethal disease. A major problem with CCA surveillance is the lack of reliable biomarkers, therefore, still less no significant aspects of client-centered therapy in clinical treatment so far. Here, we established a 25th week thioacetamide (TAA)-induced cholangiocarcinoma rat cell line model named Chang Gung CCA (CGCCA), aim to figure out the early alterations of cytogenetics, molecular and protein expressed characteristics of CCA. Array comparative genomic hybridization (aCGH) and Spectral karyotyping (SKY), gene expression microarray and immunohistochemistry were performed on either rat CCA tissues or CGCCA cell line in this study. Our results showed complicated alterations of genetic gain or loss on different chromosomal regions could be observed. The data compared with the gene expression profile, thirty-three genes aberrations could be further identified; for example, tumor metastasis-related genes ANXA1 and CLCA3, the genes MMP7 and MMP12 are related with tumor invasion, and proliferation-related genes PKM2 and OSMR have been pinpointed; The number of chromosome ranging between 50 to 56 diplody (2n); despite the apparently high incidence of chromosomal translocation was revealed by cytogenetic analyses, ring and/or giant rod marker chromosomes were detected in almost every CGCCA cells, and the genetic materials are mainly included chromosomes 4 and 8. Herein, we concluded ANXA1, CLCA3, MMP7, MMP12, PKM2 and OSMR genes could be considered as potential biomarkers for the risk of disease. Supernumerary ring or giant rod marker chromosomes could also be considered as a characteristic may be involved in the late stage of CCA. However, the genes involved in the tumorigenesis should be further investigated the function of the genes. In order to verify the clinical significance and potentially to be as therapeutic targets in the future, to confirm onto a series of human CCA tissues are necessary.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 102nd Annual Meeting of the American Association for Cancer Research; 2011 Apr 2-6; Orlando, FL. Philadelphia (PA): AACR; Cancer Res 2011;71(8 Suppl):Abstract nr 3881. doi:10.1158/1538-7445.AM2011-3881

Molecular characterization of acquired tolerance of tumor cells to picropodophyllin (PPP)

Background

Picropodophyllin (PPP) is a promising novel anti-neoplastic agent that efficiently kills tumor cells in vitro and causes tumor regression and increased survival in vivo. We have previously reported that PPP treatment induced moderate tolerance in two out of 10 cell lines only, and here report the acquired genomic and expression alterations associated with PPP selection over 1.5 years of treatment.

Methodology/Principal Findings

Copy number alterations monitored using metaphase and array-based comparative genomic hybridization analyses revealed largely overlapping alterations in parental and maximally tolerant cells. Gain/ amplification of the MYC and PVT1 loci in 8q24.21 were verified on the chromosome level. Abnormalities observed in connection to PPP treatment included regular gains and losses, as well as homozygous losses in 10q24.1-q24.2 and 12p12.3-p13.2 in one of the lines and amplification at 5q11.2 in the other. Abnormalities observed in both tolerant derivatives include amplification/gain of 5q11.2, gain of 11q12.1-q14.3 and gain of 13q33.3-qter. Using Nexus software analysis we combined the array-CGH data with data from gene expression profilings and identified genes that were altered in both inputs. A subset of genes identified as downregulated (ALDH1A3, ANXA1, TLR4 and RAB5A) or upregulated (COX6A1, NFIX, ME1, MAPK and TAP2) were validated by siRNA in the tolerant or parental cells to alter sensitivity to PPP and confirmed to alter sensitivity to PPP in further cell lines.

Conclusions

Long-term PPP selection lead to altered gene expression in PPP tolerant cells with increase as well as decrease of genes involved in cell death such as PTEN and BCL2. In addition, acquired genomic copy number alterations were observed that were often reflected by altered mRNA expression levels for genes in the same regions.

Neuregulin/erythroblastic leukemia viral oncogene homolog 3 autocrine loop contributes to invasion and early recurrence of human hepatoma

Intrahepatic metastasis is the primary cause of the high recurrence and poor prognosis of human hepatocellular carcinoma (HCC). However, neither its molecular mechanisms nor markers for its prediction before hepatectomy have been identified. We recently revealed up-regulation of erythroblastic leukemia viral oncogene homolog 3 (ERBB3) in human HCC. Here we examined the clinical and biological significance of ERBB3 in HCC. Up-regulation of ERBB3 in HCC was strongly associated with male gender (P < 0.001), chronic hepatitis B (P = 0.002), microscopic vascular invasion (P = 0.034), early recurrence (P = 0.003), and worse prognosis (P = 0.004). Phosphorylated ERBB3 and its ligands [neuregulins (NRGs)] were detected in both HCC tissues and cells. Phosphorylation of ERBB3 could be induced by conditioned media of HCC cells and abolished by the pretreatment of conditioned media with anti-NRG antibodies or by the silencing of the endogenous NRG expression of the donor HCC cells. Human epidermal growth factor receptor 2 was required for ERBB3 phosphorylation. The downstream phosphoinositide 3-kinase/v-akt murine thymoma viral oncogene homolog pathways were primarily elicited by NRG1/ERBB3 signaling, whereas the mitogen-activated protein kinase/extracellular signal-regulated kinase pathways were elicited by both epidermal growth factor/epidermal growth factor receptor and NRG1/ERBB3 signaling. The activation and silencing of ERBB3-dependent signaling had potent effects on both the migration and invasion of HCC cells, but neither had significant effects on the proliferation of HCC cells, tumor formation, or tumor growth in vitro and in vivo.

CONCLUSION

The constitutive activation of ERBB3-dependent signaling via the NRG1/ERBB3 autocrine loop plays a crucial role in the regulation of cell motility and invasion, which contribute to intrahepatic metastasis and early recurrence of HCC. ERBB3 is a marker for the prediction of intrahepatic metastasis and early recurrence. ERBB3-dependent signaling is a candidate target for the treatment of microscopic vascular invasion and for the prevention of HCC recurrence.

New sarcomatoid cancer cell line SAR-HCV established from a hepatitis C virus-related liver tumour lesion

A sarcomatoid carcinoma cell line (SAR-HCV) was established from a malignant liver lesion of a patient infected with hepatitis C virus. SAR-HCV cells were successfully xenografted in SCID mice. Vimentin was strongly positive in cultured SAR-HCV cells, the primary tumour lesion and the xenografts. Hepatocyte paraffin 1 protein and certain cytokeratin markers, CK8, CK18 and AE1/AE3 were not detected in cultured cells, but were focally positive in the tumour lesion and xenografts, suggesting that this cancer cell line preserves some features of hepatocyte differentiation when grown in vivo. HLA class I, N-cadherin, vascular endothelial growth factor, CD44, and heat-shock protein 70 were moderately expressed in this cell line. Spectral karyotyping analysis revealed a nearly triploid karyotype, 34-63<3n>, XXY[12] with complicated genetic abnormalities of chromosomal structure in all metaphases examined. This cell line will be useful in further studying hepato-sarcomatoid carcinoma cells and in understanding carcinogenesis and epithelial-mesenchymal transition in hepatitis C virus-related liver tumour.

Identification of genetic alterations in upper urinary tract urothelial carcinoma in end-stage renal disease patients

Clinical presentations of end-stage renal disease (ESRD) patients on dialysis with upper urinary tract urothelial carcinoma (UUT-UC) are different from those with normal renal function. The pathogenesis remains unknown. We investigated the pathogenetic influence of chromosomal aberrations in patient on dialysis with UUT-UC. The chromosomal aberrations of UUT-UC specimens from seven dialysis patients were assessed by conventional comparative genomic hybridization (cCGH). Subsequently, we further investigated 20 cases by whole genome and fine-tiling oligonucleotide array-based CGH to demonstrate gains and losses, and compared with the clinicopathologic background. The chromosomal aberrations in UUT-UC specimens from dialysis patients were more complex than in bladder urothelial carcinoma (B-UC). Our data showed that gains at 5p, 7, 19q, and losses at 4q, 9p, and 15q are common in UUT-UC of ESRD patients. Gains in regions associated with DNA repair genes were noted in this study. High-stage and high-grade tumors displayed more copy number variants. In addition, female ESRD patients with UUT-UC had more frequent chromosomal aberrations than their male counterparts. In conclusion, unique chromosomal aberrations were indentified in UUT-UC in ESRD patients.

Abstract 2045: microRNA expression patterns associated with resistance to platinum-based chemotherapy in human cancer cell lines

Platinum-based compounds, for example cisplatin and oxaliplatin, are the common anti-tumor drugs that have been used worldwide effective against a multitude of cancers. However, their clinical usage is impeded by toxic side effects or by the occurrence of drug resistance. MicroRNAs (miRNAs) are a group of the non-coding RNAs that play a role in controling the post-transcriptional expression of genes. Herein, we aimed to reveal the potential role of miRNAs in platinum-based drug resistance, and analyzed the miRNAs target genes that are supposed to be related with regulating the drug resistant mechanisms. The two human cancer resistant cell lines HONE-1 and TSGH were established by treating with the platinum-based compounds up to 6µm and 15µm, respectively. We then compared the expression level of genes among the parental lines and their resistant lines series using fluorescence in situ hybridization, miRNA array, expression microarray and western blot approach. The results showed the higher proteins expression level of p53 and p21 were presented in both resistant cell lines series while compared to the parental lines. However, there was no mutation occurred in both genes, either in gene structure or gene copy number change. Moreover, four miRNAs were detected from miRNA microarray by combining the results of both resistant cell line series. They included one high-regulated hsa-miR-193b; and three low-regulated hsa-miR-202, hsa-miR-509 and hsa-miR-575. Interestingly, corresponding genes that related to these miRNAs were also identified in the expression array. These genes included DNA replication related gene CDC34; cell cycle associated genes RRM2,S100A2,CCND1,CCNE1,CDC34; apoptotic pathway correlated gene CCND1; and RRM2 which is associated with DNA synthesis. In summary, as the high-expression level of protein p53 and p21 were observed on both resistant lines series without showing the gene status aberrations or RNA expression difference, we speculated that alteration could be occurred during the period of post-translational modification, and it may further regulate signal transduction of the resistant-associated genes. Therefore, genes that were targeted by hsa-miR-202, hsa-miR-509 and hsa-miR-575 should be highly noticed, and are worthwhile to further verify their potential role as the platinum-based compounds resistant biomarkers. Besides, the overexpressed gene IL-6, down stream gene Bcl-2 was known to be involved in the formation of chemoresistance, was also observed in the resistant lines. Therefore, further understanding of the regulatory pathways of IL-6 and Bcl-2 might provide novel insight into the platinum-drug resistance in clinical pharmacotherapy.

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 2045.

Abstract 3120: Aberrant activation of ERBB3 oncogenic signaling in human hepatocellular carcinoma

Background & aims: Recent evidence that ERBB3 is responsible for tumor resistance to EGFR or ERBB2 targeted therapies highlighted its crucial role in the oncogenic signaling of EGFR family. However, its roles in hepatocelluar carcinoma (HCC) remain unclear. Methods: Expression and phosphorylation of ERBB3 was examined in HCC tissues and cells. Gene number was determined using fluorescence in situ hybridization. Roles of EGEF, ERBB2, and neuregulin in phosphorylation of ERBB3 were evaluated via small-interference RNAs to silence their expression. The effects of ERBB3 on cell proliferation, invasion and tumorigenesis were assayed in vitro and in vivo. Results: Overexpression of ERBB3 was associated with a higher recurrence (P=0.000), and a worse prognosis (P=0.004). Gain of ERBB3 gene number was found in most HCC cells. EGFR, ERBB2, neuregulin and phosphorylated ERBB3 were detected in HCC cells. Phosphorylation of ERBB3 was induced by treatment with the conditioned media of HCC cells, while it was abolished by pre-treatment of the conditioned media with the anti-neuregulin antibodies or by silencing neuregulin expression. Phosphorylation of ERBB3 was suppressed by silencing the expression of ERBB2 but not EGFR. Induction of ERBB3 phosphorylation promoted cell proliferation, invasion and colony formation, while silencing ERBB3 expression suppressed xenograft tumor formation and growth in nude mice. Conclusions: Overexpression of ERBB3, primarily attributable to gene amplification, was associated with a poor prognosis of HCC. Aberrant activation of ERBB3, via an autocrine mechanism by dimerization with ERBB2, enhanced tumorigenesis in vitro and in vivo. The oncogenic signaling of ERBB3 can be the target for anti-HCC therapy.

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 3120.

Abstract 3348: Immunophenotyping, xenotransplantability and molecular cytogenetic features of the sarcomatoid renal carcinoma cell line RCC52: Pathobiological significance

The immunobiology of sarcomatoid renal cell carcinoma (RCC) and how it has been transformed or progressed from clear cell-RCC are currently poorly understood. We analyzed a sarcomatoid renal carcinoma cell line (RCC52) derived from a primary clear cell renal carcinoma with intensive sarcomatoid differentiation, with respect to its immunophenotyping, molecular cytogenetic features and xenotransplantability. RCC52 cells grown as monolayers consisted of mostly small-sized epithelioid cells along with a small proportion of spindle/fibroblast-like cells, suggestive of growth of the sarcomatoid, but not clear cell component of the tumor. Cytofluorometric analysis revealed a phenotype of cell surface HLA-I−, E-CDH−, N-CDH−, EpCAM−, CD44+, CD54+, CD58+, URO1+ and URO10+ and cytoplasmic AE1+, E-CDH−, N-CDH+, Vimentin+, S100+ and VEGF+. Spectral karyotyping (SKY) show the chromosomal abnormalities in 22 metaphases examined to be 40-42&lt;2n&gt;,X,-Y[22]; der(2)t(2,3)(q35;q21)[20]; der(14)(14;17)(p11;q12)[22]; −3[11]; +7,+7[14]; −14[9]; −15[14]; −10[10]; −22[16]. Numerical imbalances were also assessed by comparative genomic hybridization, which are found to be consistent with the findings determined by banding and SKY. These results along with the documented genotype have established the identity of the RCC52 cell lines. Nude mouse xenografts resulting from RCC52 cell s.c. injection and the original tumor shared similar histopathology with mostly sarcomatoid elements with occasional clear cell areas, suggesting malignant potential of this cell line and the capability of sarcomatoid RCC cells to undergo transdifferentiation or dedifferentiation. The total HLA class I loss caused by the two distinctive mutations in the β2-microglobulin gene and loss of heterozygosity (LOH) in chromosome 15 observed recently (Cancer ImmunoI Immunother, 58:395-408, 2009) did not prevent sarcomatoid RCC52 cells from undergoing such transdifferentiation. Overall our results is of immunological (evasion of the host immunosurveillance) and pathobiological (progression/differentiation/transdifferentiation) significance, which forms the basis of further investigations with additional cell lines/ clones and tissues of clear cell-RCCs with sarcomatoid differentiation to confirm (i) loss HLA class I expression in most, if not all, sarcomatoid RCCs, and (ii) the proposed sequence of clear cell-RCC → fibroblast-like sarcomatoid RCC → epithelioid sarcomatoid RCC, which could in turn transdifferentiate into clear cell-RCC.

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 3348.

Abstract 330: Genomic comparison of different subtypes of renal cell carcinoma using SKY, CGH

The cytogenetic biomarkers to monitor tumor progression and treatment efficacy for renal cell carcinoma (RCC) are lacking. There are few known prognostic biomarkers that limited to tumor vascularization. In almost all sporadic clear cell RCC (ccRCC), the VHL gene in either mutated or methylated form is inactivated and often involved in cellular oxygen homeostasis. Herein, we compared different subtypes of RCC: ccRCC, chromophobe RCC (CRCC), and sarcomatoid clear cell RCC (sccRCC) in culture by using SKY and CGH. In addition, cytofluorometric analysis was performed on these tumors to give an overall immunophenotyping profile of these RCCs. By comparison of genomic characteristics of these RCC subtypes, deletion of chromosome 3p has been frequently found in sporadic ccRCC; and more complex genetic patterns of the high frequencies losses of heterozygous on chromosomes 1p, 2p, 6p, 10p, 13q, 17q, and 21q have also been documented in CRCC. However, for the sarcomatoid RCC subtype, such characteristcs have rarely been studied so far. In the current study, the genetic profile of CRCC revealed by SKY was shown: 74-84&lt;4n&gt; XXXX, dic(1;11)(p21;q21)×2, −3, −4, −4, der(10)(q21.1- qter), −11, −11, −18, −18, der(19)t(5;19)(q31;q?)×2, −21, −21[21]; and SCCRCC cell line showed: 40-42&lt;2n&gt;, X,-Y; der(2)t(2,3)(q35;q21); −3; +7,+7; der(14)(14;17)(p11;q12); −14; −15; −10; −22 [22], the data were then further confirmed by CGH for gene copy number changes of the certain specific chromosomal regions. However, for the CRCC, except loss of chromosome 21, most of genetic aberrations were different from the previous reports. On the other hand, the genetic features of current sccRCC seemed not only similar to the characteristic of ccRCC (deletion 3p), but also the genetic changes sharing the those of familial RCC (t(2;3)(q35;q21)) and papillary RCC (gain of chromosome 7 and 17, and loss of Y) documented previously. Cytofluorometric analysis revealed that there were immunophenotypic differences between CRCC and sccRCC in that surface HLA class I expression was found total loss in sccRCC, whereas CRCC expressed HLA class I abundantly on the cell surface. Furthermore, bcl-2 and URO-7 were detected in the cytoplasm of CRCC, but not in sccRCC. On the other hand, CD54 was shown on cell surface; AE3, CD44v6, Hsp70, S100-β, URO-2, URO-5, URO-9 on cell cytoplasm only observed on sccRCC. In conclusion, gain of chromosome 7 and the region harbored the oncogene c-Met were found in sccRCC, which could be related with the expression of pY1349 HGFR/c-Met associated with a high pT stage and a high metastasis rate. Therefore, it is worth to further investigate the role of c-Met and its ligand HGF in sccRCC tumorigenesis, and may help to develop clinical therapeutic strategies in sccRCC. Moreover, the immunobiological evidences clarified the significant profile of these subtypes, the information is useful on predicting the patients 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 330.

Expression of ezrin is associated with invasion and dedifferentiation of hepatitis B related hepatocellular carcinoma

Background

Hepatocellular carcinoma (HCC) is the fifth most common malignancy in the world and constitutes the leading cause of cancer-related death among men, and second among women in Taiwan. Liver cirrhosis and HCC are relatively prevalent, and 80% to 85% of the patients with these conditions have positive results for hepatitis B surface antigen in Taiwan. Only 5% of the general population is seronegative for all hepatititis B virus (HBV) markers. This is the first study to determine the role of ezrin upon HBV HCC cell and patients with HBV HCC undergoing hepatectomy

Methods

Immunohistochemical study with ezrin in 104 human HBV-HCC cases were carried out to investigate its association with the clinicopathological features and the outcomes of 104 HBV-HCC patients undergoing hepatetomy. In addition, DNA constructs including the wild type ezrin (wt-ezrin) and mutant ezrin Tyr353 (Y353) were transfected into Hep3B cell to study its role in tumor invasion and differentiation.

Results

HBV HCC patients with ezrin over-expression independently have smaller tumor size, cirrhotic liver background, poor tumor differentiation, and more vascular invasion. Ezrin expression status has no impact on survival for HBV-HCC patients undergoing hepatectomy. The in vitro assay showed that wt-ezrin Hep3B cells have a significant higher level of AFP secretion and higher invasion ability as compared with the control and Y353- ezrin Hep3B cells.

Conclusion

Ezrin over-expression contributed to de-differentiation and invasion of HBV-HCC cell. HBV-HCC patients with ezrin over-expression were independently associated with tumor with smaller size, cirrhotic liver background, poor differentiation, and vascular invasion.

Thioredoxin-interacting protein: an oxidative stress-related gene is upregulated by glucose in human prostate carcinoma cells

Thioredoxin-interacting protein (TXNIP), also known as vitamin-D(3) upregulated protein 1, interacts with reduced thioredoxin. This protein modulates the cellular redox state and plays a role in stress-induced cellular apoptosis. This study examined TXNIP gene expression in prostate cancer cells. In vitro studies by immunoblot assay have shown that elevated glucose levels (1-15 mM) upregulate TXNIP gene expression two- to fourfold in human prostate carcinoma cells (LNCaP) and hepatocellular carcinoma cells (HepG2). Transient gene expression assays reveal that the promoter activity of the TXNIP gene is upregulated by glucose, 3-O-methylglucose, and maltose, but not by mannitol. These results suggest that glucose and 3-O-methylglucose induce TXNIP expression through both glucose metabolism-dependent and -independent pathways. Cotransfection of a plasmid expression carbohydrate response element-binding protein (ChREBP) with a TXNIP reporter vector into LNCaP cells dramatically enhances reporter activity in a low glucose (1 mM) condition. The effects of glucose are apparently mediated in a region located -341 to -324 bp upstream of the translational starting point of the TXNIP gene as indicated by 5'-deletion and site-directed mutagenesis reporter assays. Mutation of the putative carbohydrate response element (ChoRE) from CACGAGGGCAGCACGAG to TTTGAGGGCAGCACGAG abolishes glucose upregulation of TXNIP promoter activity. The present study demonstrates that TXNIP is transcription induced in both LNCaP and HepG2 cells in an increased glucose metabolism-dependent or -independent response, and a putative glucose regulatory system including ChREBP and ChoRE is needed for glucose-induced TXNIP gene in human prostate carcinoma cells.

Cytogenetic and expression profiles associated with transformation to androgen-resistant prostate cancer

BACKGROUND

The mechanisms underlying the progression of prostate cancer to androgen-resistant cancer are still not fully understood. Here, we studied the genetic events associated with this transformation.

METHODS

The androgen sensitive prostate cancer cells line LNCaP-FGC and its androgen resistant subline LNCaP-r were investigated using SKY, CGH, and cDNA microarray.

RESULTS

Karyotypically, several additional chromosomal aberrations were seen in LNCaP-r as compared to the parental line. CGH also revealed unique net chromosomal alterations in LNCaP-r compared to LNCaP-FGC, including gain of 2p13-23, 2q21-32, and 13q and loss of 6p22-pter. cDNA microarray analysis identified several genes involved in DNA methylation, such as DNMT2, DNMT3a, and methyl-CpG binding domain protein 2 and 4 that were higher expressed in LNCaP-r. Interestingly, androgen responsiveness of LNCaP-r was restored after treated with DNA methyltransferase inhibitor.

CONCLUSIONS

Our findings may serve as a basis for molecular dissection of the mechanisms involved in development of androgen resistant prostate cancer.

Prognostic impact of immunohistochemical expression of ezrin in highly malignant soft tissue sarcomas

PURPOSE

Ezrin is a cytoskeleton linker protein that is actively involved in regulating the growth and metastatic capacity of cancer cells. It has recently been reported to be involved in dissemination of pediatric soft tissue sarcoma (STS).

EXPERIMENTAL DESIGN

To further evaluate the prognostic value of ezrin in STS progression, we screened 50 primary STSs of high malignancy grade using immunohistochemistry. At the initial surgery, all patients were without local or distant metastasis. The expression was then compared with the outcome during follow-up for at least 4 years or until the patients' death.

RESULTS

Twenty-five of the 50 STSs analyzed (50%) showed ezrin immunoreactivity in the membrane and cytoplasm of the tumor cells. A significant association was shown between positive expressions of ezrin and death in disease as well as overall survival (P = 0.014 and 0.007, respectively). Similarly, ezrin expression was significantly associated with development of distant metastasis during follow-up (P = 0.031), also excluding locally recurrent disease (P = 0.049). The relative abundance of metastasis in ezrin-positive cases was observed both over time and irrespective of time. In comparison with clinical, histopathologic, and genetic characteristics of the STSs, ezrin expression was found to correlate significantly with an infiltrative growth pattern outside the tumor capsule as well as with copy number gain of chromosomal region 9cen-q22.

CONCLUSION

Our findings suggest that ezrin immunoreactivity could be valuable as an additional prognostic marker in highly malignant STSs and support a causative role of ezrin in STS tumor dissemination.

Immunophenotypic and molecular cytogenetic features of the cell line UP-LN1 established from a lymph node metastasis of a poorly-differentiated carcinoma

A lymph node metastatic cell line (UP-LN1) was established in vitro from a poorly-differentiated epithelial tumor, and characterized for immunobiological and molecular cytogenetic profiles. The morphology of UP-LN1 cells when grown as monolayers was unique in that, apart from typical colonies of adherent epithelial cells, many loosely attached round cell colonies emerged on and around the patches of epithelial cells. By means of immunofluorescence/flow cytometric analysis, UP-LN1 cells showed selective expression of cytokeratin markers AE1 and CK20, but expressed AE3 and CK7 poorly. The expression of CEA and CK20 but not CK7 in UP-LN1 cells was also exhibited in the tumor biopsy by immunohistochemistry, suggesting a gastrointestinal origin of this tumor. Down-regulation of HLA-class I and other surface molecules including ICAM-1, CD44s, CD44v5, CD44v6 and E-cadherin were observed, which all pointed to a progressive/invasive phenotype of the tumor. Spectral karyotyping revealed a hypertriploid (approximately 3n) chromosome content with 73-76 chromosomes, including numerical alterations and translocated derivative chromosomes. Seven different translocation chromosomes were observed, four of which involved chromosome 19. Numerical imbalances were also assessed by comparative genomic hybridization. This cell line should be useful for further studies of tumor invasion and metastatic processes because of the unusual in vitro and in vivo immunobiological and genetic characteristics observed.

Insulin-like growth factor type 1 receptor expression correlates to good prognosis in highly malignant soft tissue sarcoma

PURPOSE

To evaluate known and suggested prognostic markers, especially insulin-like growth factor type 1 receptor (IGF-1R), in highly malignant soft tissue sarcomas (STS).

EXPERIMENTAL DESIGN

A cohort of 101 patients with primary STS of high malignancy grade was studied with respect to development of metastasis, local recurrence, and survival during a minimum of 5 years follow-up. All tumors were analyzed by immunohistochemistry for expression of Ki-67, p53, p27, Bcl-2, IGF-1R, and microvessel density. The traditional clinical variables size, malignancy grade (3 or 4), necrosis, mitotic frequency, infiltrative tumor growth, vascular invasion, depth, and surgical margins were also evaluated.

RESULTS

A significant association was shown between high expression of IGF-1R and favorable outcome. Among STS with positive IGF-1R immunoreactivity, cases with high expression (76-100% positive cells) had the best outcome, whereas cases with the lowest expression (1-25% positive cells) had the worst. As expected, large tumor size (>11 cm), presence of necrosis, high mitotic count, intralesional surgery, and deep location were all significantly associated with poor outcome, both in univariate and multivariate analyses. No difference in outcome was observed between cases of malignancy grade 3 versus 4, whereas the included and more objective variables necrosis and mitotic count were found to be reliable prognostic markers.

CONCLUSION

IGF-1R expression is a common feature of highly malignant STS. Further elucidation of the role of IGF-1R and the IGF system in STS may both provide a basis for development of new prognostic tools in STS, as well as shed light on the basic mechanisms of the STS development.

Insulin-Like Growth Factor Type 1 Receptor Expression Correlates to Good Prognosis in Highly Malignant Soft Tissue Sarcoma

Purpose: To evaluate known and suggested prognostic markers, especially insulin-like growth factor type 1 receptor (IGF-1R), in highly malignant soft tissue sarcomas (STS).

Experimental Design: A cohort of 101 patients with primary STS of high malignancy grade was studied with respect to development of metastasis, local recurrence, and survival during a minimum of 5 years follow-up. All tumors were analyzed by immunohistochemistry for expression of Ki-67, p53, p27, Bcl-2, IGF-1R, and microvessel density. The traditional clinical variables size, malignancy grade (3 or 4), necrosis, mitotic frequency, infiltrative tumor growth, vascular invasion, depth, and surgical margins were also evaluated.

Results: A significant association was shown between high expression of IGF-1R and favorable outcome. Among STS with positive IGF-1R immunoreactivity, cases with high expression (76-100% positive cells) had the best outcome, whereas cases with the lowest expression (1-25% positive cells) had the worst. As expected, large tumor size (&gt;11 cm), presence of necrosis, high mitotic count, intralesional surgery, and deep location were all significantly associated with poor outcome, both in univariate and multivariate analyses. No difference in outcome was observed between cases of malignancy grade 3 versus 4, whereas the included and more objective variables necrosis and mitotic count were found to be reliable prognostic markers.

Conclusion: IGF-1R expression is a common feature of highly malignant STS. Further elucidation of the role of IGF-1R and the IGF system in STS may both provide a basis for development of new prognostic tools in STS, as well as shed light on the basic mechanisms of the STS development.

Molecular cytogenetic characterization of primary cultures and established cell lines from non-medullary thyroid tumors

To further delineate the role of chromosomal aberrations in non-medullary thyroid tumors, we performed cytogenetic analyses of established thyroid cancer cell lines and primary tumors using spectral karyotyping (SKY), G-banding and comparative genomic hybridization (CGH). Five of the primary thyroid tumors revealed an abnormal karyotype. In a follicular thyroid carcinoma, we observed two translocations t(2;10), t(2;5) and losses of chromosomes 10p and 22. In a papillary thyroid carcinoma (PTC), a balanced translocation t(3;15) was revealed, while a case of metastatic PTC carried several clonal translocations involving ten different chromosomes. Numerical aberrations were observed in two of the five follicular adenomas analyzed, both leading to gain of chromosome 7 material. Furthermore, we cytogenetically characterized the three established thyroid cancer cell lines CGTH W-1, ARO and DRO. SKY, in combination with G-banding, revealed structural and numerical karyotypic abnormalities in all three cell lines and the breakpoint regions partly overlapped those of the primary tumors. The copy number changes detected by CGH correlated well with the karyotypic findings and demonstrated high-level amplifications in chromosomes 1, 5, 7, 8, 9, 11 and 19. The results provide evidence of chromosomal regions involved in non-medullary thyroid tumorigenesis, while further characterization of the observed translocations may lead to the identification of novel fusion oncogenes for thyroid cancer.

Loss of chromosome 13q is a frequently acquired event in genetic progression of soft tissue sarcomas in the abdominal cavity

Soft tissue sarcomas (STSs) arising in the abdominal cavity constitute a group of aggressive tumours, typically of very large size and with a high recurrence rate in the affected patients. While some distinct genetic etiologies have been described, the genetic background of this tumour group is not well characterised. Here we have assessed gross chromosomal alterations in a series of such tumours obtained from 26 patients. CGH alterations were found in tumours from 23 of the patients (88%), the most frequent being loss of 13q21 (46%) and gain of 17p and/or q (46%). Furthermore, mutations of C-KIT exon 11 were demonstrated in five tumours from four patients, and the two myxoid liposarcomas exhibited a translocation t(12;16)(q13;p11). From the pattern of chromosomal alterations detected, a genetic progression of events was clearly evident in the tumours. Taken together with analysis of subsequent relapses from the same patients, the common CGH alteration +12q13 was suggested to be a relatively early event in the genetic progression, similar to t(12;16)(q13;p11) and C-KIT mutations. Moreover, -1p21-22, -13q21, -14q, -Xp22, +9q34, +17p, +17q, and +20q13 would all represent relative later events. The most consistent alteration was loss of 13q, that was found to target the 13q14-21 and 13q34 regions as determined by CGH and Southern blot analyses. Loss of 13q was identified independently of +12q13 and C-KIT mutation and the patient's sex, and was observed in all common subtypes of STS, suggesting that it is a general and late event in the genetic progression. The findings provide a starting point for further dissection of the target genes involved in development of STSs in the abdominal cavity.

Characterization of large chromosome markers in a malignant fibrous histiocytoma by spectral karyotyping, comparative genomic hybridization (CGH), and array CGH

In this study, we characterized the chromosomal composition of an intra-abdominal soft tissue sarcoma diagnosed as a malignant fibrous histiocytoma (MFH). By applying a combination of spectral karyotyping, G-banding, and comparative genomic hybridization (CGH), this case was shown to carry large chromosome markers with material mainly from chromosomes 6 and 8. Further characterization of this unique tumor revealed high-level amplifications at the 6q21 approximately q23, 8p21 approximately pter, 8q24 approximately qter, and 12q13 approximately q21 regions. Using array CGH, these amplified regions were found to include MASL1 in 8p, as well s MDM2 and CDK4 in 12q, which have been shown to be amplified in MFH. Similarly, gains of 6q and 8q have also been seen in MFH. In conclusion, our study demonstrates the occurrence of large chromosome markers in MFH and suggests that the regions 6q21 approximately q23, 8p21 approximately pter, 8q24 approximately qter, and 12q13 approximately q21 might harbor oncogenes that could play a role in MFH's tumorigenesis. In addition, gain of 12q13 approximately q21, which is typical of well-differentiated liposarcoma, may also occur in MFH, supporting the previously suggested overlap in genetic etiologies between these two tumor types.