A Study to Investigate the Role of Noncoding RNA miR146 Alpha as a Potential Biomarker in Prostate Cancer

There is a need for additional biomarkers for the diagnosis and prognosis of prostate cancer. MicroRNAs are a class of non-protein coding RNA molecules that are frequently dysregulated in different cancers including prostate cancer and show promise as diagnostic biomarkers and targets for therapy. Here we describe the role of micro RNA 146 a (miR-146a) which may serve as a diagnostic marker for prostate cancer, as indicated from the data presented in this report. Also, a pilot study indicated differential expression of miR-146a in prostate cancer cell lines and tissues from different racial groups. This report provides a novel insight into understanding the prostate carcinogenesis.

A health disparities study of MicroRNA-146a expression in prostate cancer samples derived from African American and European American patients

Considering the prevalence of prostate cancer all over the world, it is desired to have tools, technologies, and biomarkers which help in early detection of the disease and discriminate different races and ethnic groups. Genetic information from the single gene analysis and genome-wide association studies have identified few biomarkers, however, the drivers of prostate cancer remain unknown in the majority of prostate cancer patients. In those cases where genetic association has been identified, the genes confer only a modest risk of this cancer, hence, making them less relevant for risk counseling and disease management. There is a need for additional biomarkers for diagnosis and prognosis of prostate cancer. MicroRNAs are a class of non-protein coding RNA molecules that are frequently dysregulated in different cancers including prostate cancer and show promise as diagnostic biomarkers and targets for therapy. Here we describe the role of micro RNA 146a (miR-146a) which may serve as a diagnostic and prognostic marker for prostate cancer, as indicated from the data presented in this report. Also, a pilot study indicated differential expression of miR-146a in prostate cancer cell lines and tissues from different racial groups. Reduced expression of miR-146a was observed in African American tumor tissues compared to those from European Whites This report provides a novel insight into understanding the prostate carcinogenesis.

Abstract 3065: Role of noncoding RNA miR 146 alpha and let 7c in epithelial mesenchymal transition, proliferation, and cancer stem cell-like transformation analyzed by gene expression studies in a cohort of prostate cancer patients

Mir 146 alpha and let 7c are considered tumor suppressor miRs and are responsible for downregulating polycomb repressor proteins like EZH2, SUZ12, etc., and thereby prevent epithelial-mesenchymal transition (EMT),proliferation, spheroid formation and metastasis in prostate cancer cells. In this study, we investigated the role of these microRNAs in a cohort of 105 patients, both White (CA) and African American (AA), by gene expression studies using real-time PCR techniques. Our results showed definite downregulation of these noncoding RNAs in the cDNAs obtained from the matched biopsy samples of normal and cancer tissues. We further transfected these miR full-length constructs in PC3 prostate cancer cell lines and validated their effects by downregulation of their target 3'UTR target mRNAs. Our results showed decrease in EMT markers ALDH, increase in EMT marker E-cadherin, decrease in cell proliferation and spheroid formation; fluorescence microscopy studies showed a decrease in CD44-positive cells in the spheroids, signifying a possible hindrance in the growth of cancer stem cells (CSCs). Thus, miR 146 alpha and let7c could be ideal targets for diagnosis, prognosis and therapeutic intervention.

Citation Format: Hirendra N. Banerjee, Fazlul Sarkar, Myla Worthington, Sasha Hodge, Mukesh Verma, Santosh Mandal. Role of noncoding RNA miR 146 alpha and let 7c in epithelial mesenchymal transition, proliferation, and cancer stem cell-like transformation analyzed by gene expression studies in a cohort of prostate cancer patients [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 3065.

Abstract 120: A study of in vitro and in vivo effects of a novel peptide and rhenium compounds on prostate cancer

Emerging evidence suggests that acquisition of the epithelial-to-mesenchymal transition (EMT), a process that resembles the genesis of cancer stem-like cells, contributes to tumor aggressiveness and is mediated by deregulated expression of microRNAs (miRNAs), such as miR-200 and let-7 family. Loss of miR-200 expression results in the over-expression of Lin28B, which is prevalent in human Prostate Cancer( PCa) . Lin28B is also known to block the processing of another miRNA (pre-let-7 and pri-let-7), resulting in decreased mature let-7, thereby leads to increased Suz12 and EZH2 expression, which are important components of the polycomb repressive complex 2 (PRC2). Thus, over- expression of Lin28B and loss of miR-200 and let-7 appear to be responsible for PCa aggressiveness. A group of novel rhenium compounds have shown promising anti-cancer properties in various cancer cell lines tested in our laboratories. Our current investigations show that re-expression of miR-200b, miR-200c, and let-7 could be achieved by treating cells with our newly developed rhenium compounds by down-regulating the expression of Lin28B and EZH2. Based on our preliminary results, we hypothesize that over-expression of Lin28B leads to the acquisition of invasive and metastatic characteristics in PCa cells (EMT-phenotype cells) via down-regulation of miR-200b and miR-200c, resulting in increased expression of Suz12, ZEB1, and ZEB2. We also hypothesize that over-expression of Lin28B represses the maturation of let-7 family, leading to increased expression of EZH2, and these processes can be attenuated by treatment of cells with novel rhenium compounds in vitro. Our experiments were done on prostate cancer cell lines derived from both Caucasian(CA) and African American (AA)patients and also biopsy samples obtained from both CA and AA patients at Henry Ford Hospital and Karmanos Cancer Center of Wayne State University, Detroit, MI. We confirmed using gene expression studies by micro array and Real-Time PCR and then data analysis by Ingenuity software systemthe validity of our hypothesis and continued our research by testing one of these rhenium compounds-RPR1 on prostate cancer model of nude mice at Greenbaum Cancer Center(GCC) of University of Maryland at Baltimore. In vitro studies by Real -Time PCR, Flow Cytometry, Western Blotting ,Smart-Flare technology, cell death and proliferation assays along with inhibition of spheroid forming assays showed efficacy of these rhenium compounds as anti cancer agents. In vivo studies also showed decrease of tumor volume and mass ,no toxicity, thus efficacy of these novel drugs. ACKNOWLEDGEMENT: Supported by NIH- 3R01CA164318-03S1 and NIH-T-34-GM100831, a NSF-VESTEM award and NSF-LSAMP award .

Citation Format: Hirendra N. Banerjee, Sasha Hodge, William Kahan, Santosh Mandal, David Weber, Rena Lapidus, Fazlul Sarkar, Somiranjan Ghosh. A study of in vitro and in vivo effects of a novel peptide and rhenium compounds on prostate cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2017; 2017 Apr 1-5; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2017;77(13 Suppl):Abstract nr 120. doi:10.1158/1538-7445.AM2017-120

Abstract 4831: An investigation to study the role of novel rhenium compounds on onco miR's and oncogenes involved in epithelial mesenchymal transition of prostate cancer cell lines derived from African American and Caucasian patients

In this research, we seek to evaluate the efficacy of novel rhenium compounds as a novel targeted agent against prostate cancer (PCa) in pre-clinical model system. Since the incidence and aggressiveness of Pca is more prevalent in African Americans (AA) patients than Caucasian Americans (CA), we first assessed the relevance of genes Lin28B, EZH2, miR-200, and let-7 expression in human PCa tissue specimens for characterizing tumor aggressiveness, since these genes are involved in the process and also epithelial-mesenchymal transition(EMT).We also assessed whether these markers are deregulated by rhenium compounds using PCa cell lines. We tested the two novel rhenium compounds ie. Rhenium pentylcarbonato complexes (RPC), fac-(CO)3(á-diimine)ReOC(O)OC5H11 (where, á-diimines are 2,2’-bipyridyl and neocuproin for anticancer properties on PCa cell lines for apoptosis and cell death, and their bioactivity for anti-proliferative, anti-migratory and antispheroid forming capabilities, respectively on EO6-AA and MDA,Pca cell lines(from AA patients) and LNCAP,PC3 (from CA patients). We also studied the expression of miR-146á in these cell lines and Pca tissue specimens, since it is reported to be overexpressed in cancer cells for tumor survival advantage, regulated by down-regulating iNOS, the nitric oxide synthesizing gene. Our initial results of Real Time PCR,Western Blotting,MTT assay,smart flare assay,flow cytometry, in situ cytochemistry(TUNEL) and spheroid forming assays showed that these drugs have cytotoxic,anti proliferative and anti spheroid forming properties,can induce apoptosis in the Pca cell lines tested and can downregulate some of the onco miR's and onco genes involved in Pca aggressiveness and EMT conversions as tested by the expression profiles of miRNAs (miR-200b, miR-200c, and let-7 family) by RT-PCR, and the protein expression of EZH2, Suz12, and Lin-28B by Western Blots. It is important to emphasize here that an estimated 40,000 men die of PCa every year in the US and each year about 60,000 men will develop castrate resistant PCa for which newer drugs are needed. Therefore, our work will contribute towards the development of a novel therapy that may translate into an effective treatment regimen against PCa and is highly relevant to the mission of both basic and translational cancer researchers.

ACKNOWLEDGEMENT: Supported by a NCI disability supplement to NIH- grant# R01CA164318 and NIH-MARC

NIGMS,grant# 5 T34 GM 100831-4.We are grateful to Dr.Li, Dr.S.Banerjee and Ms.S.Ali of Detroit Medical Center,MI,USA for their support and help in conducting this research.

Citation Format: Hirendra N. Banerjee, Jameel Joyner, Alexis Barfield, B Morris, D Bell, William Kahan, Monet Stevenson, D Crummity, K Prabhakaran, Santosh Mandal, Fazlul Sarkar. An investigation to study the role of novel rhenium compounds on onco miR's and oncogenes involved in epithelial mesenchymal transition of prostate cancer cell lines derived from African American and Caucasian patients. [abstract]. In: Proceedings of the 107th Annual Meeting of the American Association for Cancer Research; 2016 Apr 16-20; New Orleans, LA. Philadelphia (PA): AACR; Cancer Res 2016;76(14 Suppl):Abstract nr 4831.

Abstract 4840: The role of miR-146a and novel Rhenium compounds on prostate cancer cell lines derived from African Americans and European American patients

African American (AA) men have disproportionately high incidence and mortality rates of prostate cancer (PCa) compared to other ethnic groups in the United States. The identification of molecular factors that contribute to this disparity could improve diagnosis and may predict therapeutic efficacy. MicroRNA-146a (miR-146a) suppresses PCa transformation from androgen-dependent to -independent state, and suppresses a kinase coding gene which reduces cell proliferation, invasion and metastasis. It is anticipated that miR-146a and other miRNAs may one day become biomarkers for clinical diagnosis and prognosis of several types of cancer including PCa. Novel rhenium compounds have shown anti-cancer properties especially in PCa. Therefore, the purpose of this study was to determine the expression of miR-146a in PCa cell lines derived from AA and European American (EA) patients. We also investigated the anti-cancer properties of two novel organorhenium pentylcarbonate (RPC) compounds. Relative levels of miRNA expression was determined by qRT-PCR, miRNA plate assay and smart flare technology after isolating total RNA from the cells and the exosomes from the tumor microenvironment. Cytotoxicity studies of the RPC compounds were done by using MTT and Trypan Blue assay. Our data showed a several fold increase in the expression of miR-146a in PCa cells derived from AA patient in comparison to cells derived from EA patients and a benign cell line. The RPC compounds showed bioactivity in all the PCa lines. To date, we are unaware of any studies that compared the miR-146a expression in PCa cells derived from the two racial groups. Our study suggests that miR-146a is up-regulated in PCa cells derived from AA patient compared to EA patient, which could possibly contribute to the aggressiveness associated in AA patients. We also found that the novel organorhenium compounds are bioactive with anti-cancer properties. Our results warrant further studies which are being done by our laboratory for assessing the mechanistic role of miR-146a associated with the anti-cancer activity of rhenium compounds and the role of miR-146a to define the racial disparity in PCa patients.

Acknowledgment: This research was supported by a grant from the Borroughs Wellcome Fund, NSF-LSAMP, NIH-MARC and a Disability Supplement grant from NIH.

Citation Format: Monet Stevenson, Jameel Joyner, Khadija Dildar, Oladipo Adedeji, Krishnan Prabhakaran, Hirendra N. Banerjee, Santosh Mandal, Fazlul Sarkar. The role of miR-146a and novel Rhenium compounds on prostate cancer cell lines derived from African Americans and European American patients. [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 4840. doi:10.1158/1538-7445.AM2015-4840

Abstract 3552: Differential expression of microRNAs in gastrointestinal neuroendocrine tumors

BACKGROUND: Various staging and grading systems are used to classify the gastrointestinal neuroendocrine tumors (GNTs). These systems attempt to stratify tumors, in order to predict survival after resection and the rate of progression to metastatic disease. At present, no specific molecular markers are available for diagnosis, prognosis or therapeutic targeting of GNTs. Microarray profiling analysis for the expression of miRNAs was performed on GNTs of stomach, small intestine, appendix, colon and rectum.

MATERIALS AND METHODS: Database search was carried out for patients with GNTs and pathological staging was performed in accordance with AJCC Cancer Staging manual (7th ed). The tumors evaluated included stomach (Stage I & II: 8 cases, Stage III&IV: 3 cases) , Ileum and cecum (Stage I and II:5, Stage III& IV: 17), appendix (Stage I &II: 3, goblet cell carcinoid: 7), and rectum (Stage I and II: 15, Stage III and IV: 3 cases). Kaplan Meir analysis revealed a worse overall survival of Stage III and IV tumors in comparison to Stage I and II in all subgroups. Formalin Fixed Paraffin Embedded (FFPE) archival tissue was obtained. Total RNA was isolated from FFPE tissue using the RNeasy Kit (Qiagen, Valencia, CA, USA). RNA was quantified and its purity was evaluated by the absorption ratio at 260/280nm using NanoDrop 2000 (Thermo Scientific, Pittsburgh, PA, USA). The microRNA profiling was performed by LC Sciences (Houston, TX) using miRBase v20 and data was normalized using selective housekeeping miRNAs.

RESULTS: The most significantly altered miRNAs amongst various groups are tabulated (Table no.1)

CONCLUSION: Stage III and IV GNTs are biologically distinct in comparison to Stage I and II GNTs. There is a significant up-regulation or down-regulation of specific miRNAs in these tumors. Bioinformatics analysis and further validation by RT-PCR are being performed which will likely provide information on the role of specific genes regulated by these miRNAs in GNTs.

Table no.1: Differential expression of miRNAs in GNTsmiRNAIleum Stage III and IV (G1)Ileum Stage I and II (G2)log G2/G1miR-9-5p(Tumor suppressor gene, TSG)621005-4.02miR-424-5p(TSG)4962853-2.52miR-376c-3p (Tumor oncogene, TO)553862.68miR-301a-3p (TO)7951252.66miRNAStomach Stage III and IV (G1)Stomach Stage I and II (G2)log G2/G1miR-18a-5p (TSG)2843635.39miR-19a-3p (TSG)2864795.17miR-6722-5p (TO)1211278-3.4miR-6858-3p (TO)112820-2.87miRNARectum Stage III and IV (G1)Rectum stage I and II (G2)log G2/G1miR-34a-5p (TSG)216933-2.11miR-150-5p (TSG)3981440-1.85miR-122-5p (TO)17131024.07miR-653-3p (TO)16272142.93miRNAGoblet cell carcinoid Stage III and IV (G1)Appendiceal carcinoid Stage I and II (G2)log G2/G1miR-642a-5p (TSG)11180-17.49miR-642b-5p (TSG)9620-17.28miR-7843-5p (TO)9916944.09miR-6775-5p (TO)134043601.70

Citation Format: Amarpreet Bhalla, Shadan Ali, Fazlul Sarkar, Anthony Shields, Amy Jencks, Romil Nathan, Vinod B. Shidham. Differential expression of microRNAs in gastrointestinal neuroendocrine tumors. [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 3552. doi:10.1158/1538-7445.AM2014-3552

Proceedings of the Indo-U.S. bilateral workshop on accelerating botanicals/biologics agent development research for cancer chemoprevention, treatment, and survival

With the evolving evidence of the promise of botanicals/biologics for cancer chemoprevention and treatment, an Indo-U.S. collaborative Workshop focusing on “Accelerating Botanicals Agent Development Research for Cancer Chemoprevention and Treatment” was conducted at the Moffitt Cancer Center, 29–31 May 2012. Funded by the Indo-U.S. Science and Technology Forum, a joint initiative of Governments of India and the United States of America and the Moffitt Cancer Center, the overall goals of this workshop were to enhance the knowledge (agents, molecular targets, biomarkers, approaches, target populations, regulatory standards, priorities, resources) of a multinational, multidisciplinary team of researcher's to systematically accelerate the design, to conduct a successful clinical trials to evaluate botanicals/biologics for cancer chemoprevention and treatment, and to achieve efficient translation of these discoveries into the standards for clinical practice that will ultimately impact cancer morbidity and mortality. Expert panelists were drawn from a diverse group of stakeholders, representing the leadership from the National Cancer Institute's Office of Cancer Complementary and Alternative Medicine (OCCAM), NCI Experimental Therapeutics (NExT), Food and Drug Administration, national scientific leadership from India, and a distinguished group of population, basic and clinical scientists from the two countries, including leaders in bioinformatics, social sciences, and biostatisticians. At the end of the workshop, we established four Indo-U.S. working research collaborative teams focused on identifying and prioritizing agents targeting four cancers that are of priority to both countries. Presented are some of the key proceedings and future goals discussed in the proceedings of this workshop.

Abstract P4-15-07: MicroRNA signature of breast cancer brain metastasis for novel targeted therapies

Rationale:

MicroRNAs (miRNAs) are recently described novel small non-coding endogenous RNAs which critically regulate cancer progression, invasion and metastasis. Altered expression of miRNAs has been proposed to control the invasive capability of cancer cells. Modulating altered miRNAs is a novel approach for targeted therapy for cancer. Breast cancer is the most common cancer among women in the US. Breast cancer-related mortality and morbidity are primarily due to metastatic disease especially brain metastasis which also impacts patients’ quality of life. Molecular mechanisms of brain metastasis of breast cancer are largely unknown.

Study Objectives:

Identifying molecular miRNA signatures in breast cancers which metastasize to the brain can assist in designing novel targeted therapies to prevent and eliminate brain metastasis.

Design:

RNA was extracted from formalin fixed paraffin embedded tumor tissues from a cohort of breast cancer patients with brain metastasis, and age, stage and follow-up matched breast cancer cases without brain metastasis. miRNA expression profiling was done using EQIXON microarray. Quantitative real-time PCR (qRT-PCR) was used to validate abnormal expression of miRNAs. Data was statistically analyzed using Kruskal-Wallis test to determine the clinical significance of the findings.

Results:

Over 2000 unique miRNA sequences were profiled in each case. The upregulated miRNAs included miR-3927-5p, miR-216b and miR-10b and the down regulated miRNAs were miR-4280, miR-3174 and miR-1244 and miR20b. Validation of the deregulated miRNAs by q RT-PCR showed statistically significant difference in the expression levels in the breast cancers with brain metastasis compared to breast cancers without brain metastasis (Kruskal-Wallis test; p < 0.001).

Conclusions:

A unique set of miRNAs were deregulated in breast cancers with brain metastasis. This panel of altered miRNAs have clinical relevance since they can be silenced by antagomirs (chemically modified anti-miRNA oligonucleotides) to treat and prevent brain metastasis. These molecular microRNA signature-based novel targeted prophylactic and therapeutic strategies could improve patients’ quality of life and overall survival in the era of personalized and precision medicine.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P4-15-07.

Targeting triple negative breast cancer cells by N3-substituted 9,10-phenanthrenequinone thiosemicarbazones and their metal complexes

Novel N(3)-substituted 9,10-Phenanthrenequinone thiosemicarbazones and their copper, nickel and palladium complexes are structurally characterized and reported along with the single crystal X-ray structures of three ligands and one nickel complex. All compounds were evaluated for their antiproliferative potential against Triple Negative Breast Cancer (TNBC) cells which have poor prognosis and no effective drugs to treat with. All compounds exhibited antiproliferative activity against these cells. Among the metal complexes evaluated, redox active copper complexes were found to be more potent. The possible mechanism for such enhanced activity can be attributed to the generation of oxidative stress, which was amenable for targeting through metal complexation.

Perspectives on new synthetic curcumin analogs and their potential anticancer properties

Curcumin is the active component of dried rhizome of Curcuma longa, a perennial herb belonging to ginger family, cultivated extensively in south and southeastern tropical Asia. It is widely consumed in the Indian subcontinent, south Asia and Japan in traditional food recipes. Extensive research over last few decades has shown that curcumin is a potent anti-inflammatory agent with powerful therapeutic potential against a variety of cancers. It suppresses proliferation and metastasis of human tumors through regulation of various transcription factors, growth factors, inflammatory cytokines, protein kinases and other enzymes. It induces apoptotic cell death and also inhibits proliferation of cancer cells by cell cycle arrest. Pharmacokinetic data has shown that curcumin undergoes rapid metabolism leading to glucuronidation and sulfation in the liver and excretion in the feces, which accounts for its poor systemic bioavailability. The compound has, therefore, been formulated and administered using different drug delivery systems such as liposomes, micelles, polysaccharides, phospholipid complexes and nanoparticles that can overcome the limitation of bioavailability to some extent. Attempts to avoid rapid metabolism of curcumin until now have been met with limited success. This has prompted researchers to look for new synthetic curcumin analogs in order to overcome the drawbacks of limited bioavailability and rapid metabolism, and gain efficacy with reduced toxicity. In this review we provide a summarized account of novel synthetic curcumin formulations and analogs, and the recent progress in the field of cancer prevention and treatment.

Perspectives on new synthetic curcumin analogs and their potential anticancer properties

Curcumin is the active component of dried rhizome of Curcuma longa, a perennial herb belonging to ginger family, cultivated extensively in south and southeastern tropical Asia. It is widely consumed in the Indian subcontinent, south Asia and Japan in traditional food recipes. Extensive research over last few decades has shown that curcumin is a potent anti-inflammatory agent with powerful therapeutic potential against a variety of cancers. It suppresses proliferation and metastasis of human tumors through regulation of various transcription factors, growth factors, inflammatory cytokines, protein kinases and other enzymes. It induces apoptotic cell death and also inhibits proliferation of cancer cells by cell cycle arrest. Pharmacokinetic data has shown that curcumin undergoes rapid metabolism leading to glucuronidation and sulfation in the liver and excretion in the feces, which accounts for its poor systemic bioavailability. The compound has, therefore, been formulated and administered using different drug delivery systems such as liposomes, micelles, polysaccharides, phospholipid complexes and nanoparticles that can overcome the limitation of bioavailability to some extent. Attempts to avoid rapid metabolism of curcumin until now have been met with limited success. This has prompted researchers to look for new synthetic curcumin analogs in order to overcome the drawbacks of limited bioavailability and rapid metabolism, and gain efficacy with reduced toxicity. In this review we provide a summarized account of novel synthetic curcumin formulations and analogs, and the recent progress in the field of cancer prevention and treatment.

Abstract 4485: Anticancer properties of novel rhenium compounds against human cancer cell lines

Cisplatin, carboplatin, oxaliplatin, and related metallodrugs are extensively being used in the treatment of a variety of cancers. Unfortunately these drugs are highly toxic and tumor becomes drug-resistance. These circumstances have led researchers to look for new cytotoxic agents that may exhibit less toxicity and devoid of drug resistance. It is believed that cisplatin and related drugs directly bind to genomic DNA through purine bases. Synthesis of new metallodrugs which does not follow the above mechanism of action might yield better drugs with less toxicity and devoid of drug resistance. Recently we have demonstrated that several anticancer rhenium compounds do not directly bind to DNA. We have synthesized numerous rhenium pentylcarbonato and acetylsalicylato complexes which include (CO)3(2,2’-Bipyridyl)ReOC(O)OC5H11 (PC-1), (CO)3(1,10-Phenanthroline)ReOC(O)OC5H11 (PC-2), (CO)3(5-Methyl-1,10-Phenanthroline)Re ReOC(O)OC5H11 (PC-3), (CO)3(2,9-Dimethyl-1,10-Phenanthroline)ReOC(O)OC5H11 (PC-4), (CO)3(5,6-Dimethyl-1,10-Phenanthroline)ReOC(O)OC5H11 (PC-5), (CO)3(4,7-Diphenyl-1,10-Phenanthroline)ReOC(O)OC5H11 (PC-6), (CO)3(2,9-Dimethyl-4,7-Diphenyl-1,10-Phenanthroline)Re ReOC(O)OC5H11 (PC-7), (CO)3(2,2’-Bipyridyl)ReOC(O)C6H4·C(O)OCH3 (ASP-1), (CO)3(1,10-Phenanthroline)ReOC(O)C6H4·C(O)OCH3, (ASP-2), (CO)3(5-Methyl-1,10-Phenanthroline)ReOC(O)C6H4·C(O)OCH3 (ASP-3), (CO)3(2,9-Dimethyl-1,10-Phenanthroline)ReOC(O)C6H4·C(O)OCH3 (ASP-4), (CO)3(5,6-Dimethyl-1,10-Phenanthroline)ReOC(O)C6H4·C(O)OCH3 (ASP-5), (CO)3(4,7-Diphenyl-1,10-Phenanthroline)ReOC(O)C6H4·C(O)OCH3 (ASP-6), (CO)3(2,9-Dimethyl-4,7-Diphenyl-1,10-Phenanthroline)ReOC(O)C6H4·C(O)OCH3 (ASP-7). The anticancer properties of the compounds were evaluated using human prostate, alveolar lung, brain, colon, and leukemia cancer cell lines and normal bone marrow cell lines. The results of this study demonstrate that these complexes have significant anticancer properties. Therefore, these complexes can potentially find applications in the treatment of these cancers.

Acknowledgment. The work at MSU was partially supported by grants from the National Institutes of Health (Grant No. G11HD038439) and Nuclear Regulatory Commission (Grant No. NRC-HQ-12-G-27-0086). The work at ECSU-UNC was partially supported by grant from the Department of Energy (TMCF/DOE grant).

Citation Format: Hirendra N. Banerjee, Deidre Vaughan, Jewe Medley, Gwyn Hyman, Christopher Krauss, Carl Parson, Santosh Mandal, Pola Olczak, Michael Mbagu, Divine Kebulu, Saroj Pramanik, Fazlul Sarkar. Anticancer properties of novel rhenium compounds against human cancer cell lines. [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 4485. doi:10.1158/1538-7445.AM2013-4485

Abstract 3296: The loss of miR-34a and activation of Notch-1 leads to aggressiveness of pancreatic cancer cells, which could be attenuated by CDF

Studies have shown that Notch-1 plays key roles in early development and also becomes activated during the development and progression of a variety of tumors including pancreatic cancer (PC), one of the most lethal malignant diseases, which is in part due to its potential for rapid growth, drug resistance, and metastasis. The expression of microRNA (miRNA) miR-34a, a potential tumor suppressor, has been reported to be decreased in many human tumors including PC, suggesting that miR-34a is a critical during tumor development and progression. Several recent experimental studies have shown an inhibitory role of miR-34a in tumor cell growth by targeting Notch-1 in various tumor cells lines derived from prostate cancer, colorectal cancer and pancreatic cancer. However, the mechanistic interrelationship between the loss of miR-34a and activation of Notch-1 has not been fully elucidated. Here, we show that the expression of miR-34a is significantly reduced in a number of PC cell line. Forced over-expression of Notch-1 by Notch-1 cDNA transfection led to decreased expression of miR-34a in AsPC-1 PC cells, which was consistent with increased tumor cell aggressiveness such as increased cell migration and sphere formation (pancreatospheres). Conversely, knock-down of Notch-1 by Notch-1 specific siRNA decreased the formation of pancreatospheres in AsPC-1 cells and cancer stem like cells (CSLCs) such as those which formed spheres. Re-expression of miR-34a by the transfection of its precursor decreased the expression of Notch-1 protein in Notch-1 over-expressing PC cells, which was consistent with a decrease in the formation of pancreatospheres. Moreover, re-expression of miR-34a also decreased angiogenesis in vitro, the production of VEGF as well as mRNA levels of Notch-1 and other CSC markers (Nanog, Oct4, and EZH2) in pancreatic CSLCs (sphere cells). Finally, we found that CDF, a novel synthetic analogue of natural compound Curcumin, could decrease cell growth, cell migration, angiogenesis in vitro, and the formation of pancreatospheres, consistent with decreased expression of Notch-1 and VEGF, and increased expression of miR-34a in PC cells and in mouse xenograft tumor model of PC. In conclusion, our findings suggest that the inhibitory effect of CDF on PC tumor growth in vitro and in vivo is in part mediated through deregulations of Notch-1 and miR-34a in PC, suggesting that further in-depth investigations are warranted.

Citation Format: Bin Bao, Shadan S. Ali, Asfar Azmi, Aamir Ahmad, Dejuan Kong, Yiwei Li, Sanjeev Banerjee, Amro Aboukameel, Subhash Padhye, Fazlul Sarkar. The loss of miR-34a and activation of Notch-1 leads to aggressiveness of pancreatic cancer cells, which could be attenuated by CDF. [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 3296. doi:10.1158/1538-7445.AM2013-3296

Abstract 241: Tumor initiating cells and FZD8 play a major role in drugresistance and tumor progression in triple negative breast cancer

Triple-negative breast cancer (TNBC) is usually associated with poor outcome in part due to lack of benefit from targeted therapy. Previous studies have shown that neoadjuvant chemotherapy before surgery was effective in the minority of women with TNBC; in contrast, the majority who had a residual tumor after treatment had a relatively poor outcome. In order to identify the mechanism by which residual cancer cells survive chemotherapy, we performed gene expression profile using CRL2335 TNBC cell line before and after treatment with cisplatin plus TRAIL. We found a significant increase in the expression of FZD8, one of the Wnt receptors, and its downstream targets LEF1 and TCF in residual tumor cells after treatment with cisplatin plus TRAIL compared with untreated controls. Inhibition of FZD8 by siRNA in the presence of cisplatin plus TRAIL reduced β-catenin and survivin levels, and increased apoptosis compared to scrambled siRNA-treated cells. In vivo, data demonstrate that cisplatin plus TRAIL treatment, significantly reduces tumor volume in nod/SCID mice. However, we found that cisplatin plus TRAIL treatment predominantly eliminated non-tumor initiating cells (non-TICs), as demonstrated by whole-body fluorescent imaging of mice injected with mammosphere-forming cells stably transfected with DsRed. This led to TIC enrichment in residual tumors, as confirmed by immunostaining for TIC markers. Moreover, an increase in FZD8 expression was observed in residual tumors treated with cisplatin and TRAIL. Taken together, our findings suggest that FZD8-mediated Wnt-signaling may play a major role in mediating resistance to chemotherapy, making it a potential target to enhance chemotherapeutic efficacy in patients with TNBC.

Citation Format: Kaladhar B. Reddy, Shuping Yin, R. Bonfil Daniel, Sanjeev Banerjee, Fazlul Sarkar, Seema Sethi. Tumor initiating cells and FZD8 play a major role in drugresistance and tumor progression in triple negative breast cancer. [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 241. doi:10.1158/1538-7445.AM2013-241

P53-independent induction of p21(waf1) pathway is preserved during tumor progression

The p21(WAF1) gene encodes a cyclin-dependent kinase inhibitor and plays an important role in controlling the cell cycle. Its expression can be induced through wild-type p53-dependent or -independent pathways. Since the p53-dependent pathway is disrupted in more than 50% of human tumors, we wondered whether the p53-independent pathway is also altered during tumor progression. In the present study, we have determined p21(WAF1) induction by mitogenic stimuli, which is known to be a p53-independent process. p21(WAF1) is induced by mitogenic stimuli in all cell lines tested regardless of the status of p53, i.e. wild-type, wild-type inactivated by SV40T or mutant, and the transformation of cells from immortal to tumorigenic and to metastatic. These results indicate that the p53-independent induction of p21(WAF1) pathway is preserved during tumor progression.

Association between COX-2 expression and effectiveness of COX-2 inhibitors in a phase II trial in patients with metastatic colorectal adenocarcinoma

AIM

The role for the cyclooxygenase-2 (COX-2) pathway in colorectal carcinogenesis has been suggested in pre-clinical models. In a previously reported phase II trial, the addition of COX-2 inhibitor celecoxib to irinotecan and capecitabine did not appear to significantly increase the activity of chemotherapy in patients with metastatic colorectal carcinoma (mCRC). We evaluated the COX-2 expression in the available tumors from enrolled patients by immunohistochemistry, as well as its correlation with clinical outcome.

PATIENTS AND METHODS

Fifty-one patients with mCRC were enrolled in the phase II study between June 2002 and November 2005. Patients received a combination of irinotecan 70 mg/m(2) over 30 min i.v. on days 1 and 8, capecitabine 1,000 mg/m(2) twice per day orally on days 1-14 and the COX-2 inhibitor celecoxib at a daily dose of 800 mg continuously. Cycles were repeated every 21 days. Formalin-fixed paraffin-embedded tumor tissue samples were available for 17 patients enrolled on this study. COX-2 expression was evaluated by immunohistochemistry and was correlated with clinical outcome.

RESULTS

In the phase II study, the objective response rate was 41%. The median time to progression was 7.7 months and median survival time was 21.2 months. Tumor COX-2 expression, by immunohistochemistry, was assessed for 17 patients enrolled in the same phase II study. While not statistically significant, the response rate was better for patients in the low COX-2 expression group, while time to progression and overall survival was longer in patients in the high COX-2 expression group. This discrepancy can be partially attributed to the small sample size.

CONCLUSION

In the previously published phase II study, the addition of celecoxib to irinotecan and capecitabine did not appear to significantly increase the activity of chemotherapy. COX-2 expression by immunohistochemistry was neither prognostic nor predictive for response.

Abstract B22: Re-expression of miR-200 by natural agents regulates the expression of PTEN and MT1-MMP in pancreatic cancer

Purpose: Membrane type-1 matrix metalloproteinase (MT1-MMP) is often activated and expressed in tumor cells with significant invasive properties, and is associated with poor prognosis of patients. This could partly be due to deregulated expression of microRNAs (miRNAs) which regulates the expression of MT1-MMP and PTEN (Phosphatase and tensin homolog) contributing to tumor invasion and metastasis.

Experimental Procedure: We initially compared the expression profile of miR-200 family, PTEN and MT1-MMP expression in six pancreatic cancer (PC) cell lines by qRT-PCR and western blot analysis. Based on our initial findings, we chose BxPC-3, MIAPaCa-2, and MIAPaCa-2-GR cells for further mechanistic studies. We assessed the effect of two separate novel agents CDF, (a synthetic analogue of curcumin) and BR-DIM (a natural agent) on PC cells.

Results: We found loss of expression of miR-200a, b, and c in chemo-resistant PC cell lines, which was correlated with loss of PTEN and over-expression of MT1-MMP. The expression of miR-200 family and PTEN was significantly re-expressed whereas the expression of MT1-MMP was down-regulated by CDF and BR-DIM treatment. Forced over-expression or silencing of miR-200c, followed by either CDF or BR-DIM treatment of MIAPaCa-2 cells altered the morphology of cells, wound-healing capacity, colony formation, and the expression of MT1-MMP and PTEN.

Conclusion: These results provide strong experimental evidence showing that the loss of miR-200 family and PTEN expression, and increased level of MT1-MMP leads to aggressive behavior of PC cells, which could be attenuated through re-expression of miR-200c by CDF and/or BR-DIM treatment, suggesting that these agents could be useful for treatment.

Abstract 4599: Comprehensive molecular oncogenomic profiling & miRNA analysis of prostate cancer

Background: Comprehensive molecular oncogenomic and microRNA (miRNA) profiling of tumors can provide tumor specific oncogenomic and miRNA signatures which can be useful to improve diagnostic accuracy, refine prognostic and predictive capabilities, and may serve as therapeutic targets. In prostate cancer (PCa) such a comprehensive analysis has not been reported. Design: DNA and RNA obtained from scant amounts of fresh frozen PCa tumor tissue samples (n=36) were profiled by (1) Mutation analysis: Sequenom Massarray & OncoCarta VI panel that profiles 238 common cancer mutations in 19 oncogenes (known predictors of response or resistance to targeted therapies);(2) Whole-genome gene expression Microarrays: Illumina Chip;(3) Single Nucleotide Polymorphisms (SNP) with genome-wide coverage:Illumina Omni microarrays. (4)miRNA analysis was done on RNA from FFPE PCa tumor tissues (n=126) using RT-PCR. Data was statistically analyzed & correlated with clinical & pathologic variables. Results: Massarray analysis identified a MET oncogene mutation, variant T992I, in a 49 year old patient with Gleason score 7 (4+3) tumor. Of the 47,224 genes analyzed by gene expression microarrays, 74 genes were significant predictors of high tumor grade by ordinal regression analysis (p<0.0001). TGIF1 was the most significant gene. Of the 731,442 SNP's analyzed, 638 significantly predicted high tumor grade by logistic regression analysis (p<0.0001). There was significant interaction between gene and SNPs in 531 SNP/gene pairs (p<0.05). Ingenuity Pathway analysis revealed the significant predictor genes (p<0.05) were involved in biological pathways for Gene Expression, Cell Cycle, Cancer,” “Inflammatory Response, Cell Death, Infection Mechanism & Cellular Assembly, Organization, Gene Expression, Cancer. P53 gene was found to be at the center hub of significant predicting pathways. Loss of miR-34a expression was found in PCa tissues consistent with the central role of p53. Conclusions: Using high throughput genomic profiling & miRNA analysis of small amounts of fresh-frozen and FFPE PCa tumor samples, we identified clinically relevant hot spot mutation in MET oncogene and several significant genes & SNPs to predict tumor grade. P53 gene is at the center hub of all significant pathways. Loss of miR-34a was consistent with p53 function in PCa. MET oncogene mutation is a novel finding, not previously reported in PCa against which small molecule inhibitors are under development. These molecular signatures may have a significant clinical impact on improving diagnostic and predictive capabilities & in designing targeted therapies to achieve the goal of personalized medicine.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 4599. doi:1538-7445.AM2012-4599

Enhanced anticancer effect of the combination of cisplatin and TRAIL in triple-negative breast tumor cells

Women with triple-negative breast cancer (TNBC) have a worse prognosis compared with other breast cancer subtypes. Hormonal or Herceptin-based therapies were found to be ineffective because of the loss of target receptors, such as ER, PR, and HER-2 amplification. Conventional chemo- and/ or radiation therapy also seems to have limited efficacy in TNBC patients. We studied the effects of cisplatin plus TRAIL on 1 normal and 2 TNBC cells in vitro. The in vitro studies indicate that cisplatin plus TRAIL significantly enhanced cell death in TNBC cell lines CRL2335 and MDA-MB-468 by approximately 60%-70% compared with approximately 10%-15% in CRL8799 normal breast cell line. Treatment with cisplatin/TRAIL also inhibited the expression of EGFR, p63, survivin, Bcl-2, and Bcl-xL in TNBC cells. Specific inhibition of EGFR and/or p63 protein in TNBC cells by small interfering RNA (siRNA) does not increase TRAIL-induced apoptosis. However, inhibition of survivin by siRNA enhances TRAIL-induced apoptosis. These observations suggested the possibility that survivin played an important role in cisplatin plus TRAIL-induced apoptosis in TNBC cells. In vivo experiments, treatment of mice with cisplatin plus TRAIL resulted in a significant inhibition of CRL2335 xenograft tumors compared with untreated control tumors. Taken together the data suggest that cisplatin plus TRAIL treatment have the potential of providing a new strategy for improving the therapeutic outcome in TNBC patients.

Abstract 5541: Daidzein protects against genistein-induced lymph node metastasis, and serve as a radiosensitizer in prostate cancer

We have previously reported that genistein, the major bioactive isoflavone of soybeans, acts as a radiosensitizer for prostate cancer (PCa) both in vitro and in orthotopic mouse models in vivo. However, pure genistein promoted increased spontaneous metastasis to regional lymph nodes, when administered alone in vivo. In contrast to genistein, a natural formulation of soy isoflavones mixture (43% genistein, 21% daidzein and 2% glycitein) did not cause increased metastasis, but like genistein, the soy mixture potentiated the therapeutic effect of radiation. We have now tested whether daidzein, the second main isoflavone of soybeans, could negate genistein-induced lymph node metastasis in PC-3 orthotopic prostate tumors in nude mice. Mice were treated with purified daidzein, or genistein or both combined; and also in conjunction with prostate tumor irradiation. Either daidzein or genistein alone or both combined caused the same extent of prostate tumor growth inhibition than the soy mixture. Treatment with daidzein alone did not increase metastasis to regional lymph nodes but still acted as a potent radiosensitizer for prostate tumors. Treatment with both genistein and daidzein combined did not cause an increase in lymph node metastasis, which is consistent with the findings obtained with the soy mixture. These studies show that pure daidzein could be the component of the soy isoflavones mixture that protects against genistein-induced lymph node metastasis. In order to gain further mechanistic insight on how daidzein negates the adverse effects of genistein, we compared the effects of each isoflavone and the soy mixture in vitro using PC-3 (androgen receptor AR-) and C4-2B (AR+) androgen independent PCa cell lines. We found that daidzein inhibited tumor cell growth and synergized with radiation in clonogenic assays but at doses higher than genistein or the soy mixture. We have previously demonstrated that genistein or the soy mixture cause tumor cell apoptosis and enhance radiation killing by inhibiting cell survival pathways activated by radiation including the repair enzyme/redox activator APE1/Ref-1 and the transcription factors HIF-1α and NF-κB. Compared to the effect of genistein or the soy mixture, daidzein treatment caused milder effects on PARP cleavage, inhibition of expression of APE1/Ref-1 and HIF-1α; and lower inhibition of HIF-1α and NF-κB DNA binding activities. These effects were reproduced in both PC-3 and C4-2B cell lines. Based on these results, we conclude that APE1/Ref-1, NF-κB and HIF-1α molecular pathways were also affected by daidzein, although to a lesser extent than genistein and soy mixture, in both AR+ and AR- PCa cancer cell lines, suggesting that this is an AR-independent mechanism. The protective effect of daidzein against lymph node metastasis induced by genistein appears to be independent of HIF-1α and NF-κB pathways, and remains to be clarified.

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 5541.

A phase II trial of 17-allylamino-17-demethoxygeldanamycin in patients with hormone-refractory metastatic prostate cancer

PURPOSE

17-Allylamino-17-demethoxygeldanamycin (17-AAG) is a benzoquinone ansamycin antibiotic with antiproliferative activity in several mouse xenograft models, including prostate cancer models. A two-stage phase II study was conducted to assess the activity and toxicity profile of 17-AAG administered to patients with metastatic, hormone-refractory prostate cancer.

EXPERIMENTAL DESIGN

Patients with at least one prior systemic therapy and a rising prostate-specific antigen (PSA) were eligible. Patients received 17-AAG at a dose of 300 mg/m2 i.v. weekly for 3 of 4 weeks. The primary objective was to assess the PSA response. Secondary objectives were to determine overall survival, to assess toxicity, and to measure interleukin-6, interleukin-8, and maspin levels and quality of life.

RESULTS

Fifteen eligible patients were enrolled. The median age was 68 years and the median PSA was 261 ng/mL. Patients received 17-AAG for a median number of two cycles. Severe adverse events included grade 3 fatigue (four patients), grade 3 lymphopenia (two patients), and grade 3 back pain (two patients). The median PSA progression-free survival was 1.8 months (95% confidence interval, 1.3-3.4 months). The 6-month overall survival was 71% (95% confidence interval, 52-100%).

CONCLUSIONS

17-AAG did not show any activity with regard to PSA response. Due to insufficient PSA response, enrollment was stopped at the end of first stage per study design. The most significant severe toxicity was grade 3 fatigue. Further evaluation of 17-AAG at a dose of 300 mg/m2 i.v. weekly as a single agent in patients with metastatic, hormone-refractory prostate cancer who received at least one prior systemic therapy is not warranted.

Copper conjugates of nimesulide Schiff bases targeting VEGF, COX and Bcl-2 in pancreatic cancer cells

Copper conjugates of Schiff base derivatives of nimesulide (1), a well-known cyclooxygenase-2 (COX-2) inhibitor, were synthesized, structurally characterized and evaluated for their COX selectivity indices and cytotoxicities on pancreatic tumor, BxPC-3 (COX-2 positive) and MiaPaCa (COX-2 negative) cell lines. Copper conjugates exhibit distorted square planar geometries as revealed by the single crystal X-ray structure determination of Cu(L1)(2) and show significant growth inhibition in both cell lines (IC50 values 3-26 microM for COX-2 positive and 5-9 microM for COX-2 negative cell line) than the parent nimesulide (35 microM for COX-2 positive and >100 microM for COX-2 negative cell line). The mechanistic pathway for the biological activity involves inhibition of vascular endothelial growth factor (VEGF) and COX inhibition, as well as down regulation of antiapoptotic Bcl-2 and Bcl-(XL) proteins.

Toxic effect of zinc on NF-κB, IL-2, IL-2 receptor α, and TNF-α in HUT-78 (Th0) cells

Zinc deficiency decreased cellular immune response. Zinc supplementation reverses this response. High concentration of zinc intake is reported to alter immune response. We hypothesize that higher concentration of zinc adversely affects T-cell immune response. In this study, we examined whether higher concentration of zinc affects expression of IL-2, IL-2Ralpha, and TNF-alpha, and NF-kappaB activation in HUT-78 (Th(0)) cells. The results show that HUT-78 cells incubated in 15, 50, and 100 microM zinc medium had significantly higher intracellular zinc contents and faster growth after 4 days of incubation, compared to the cells incubated in 1 microM zinc medium. After PMA/PHA stimulation, 1 microM zinc showed significant decreases in NF-kappaB activation, and in the levels of IL-2, IL-2Ralpha, and TNF-alpha production and mRNAs compared to 15 microM zinc. The cells incubated in higher concentrations of zinc (50 and 100 microM zinc) showed mild to moderate decreases in the levels of IL-2, IL-2Ralpha, and TNF-alpha production and mRNAs, and in NF-kappaB activation compared to those incubated in 15 microM zinc medium. These data indicate that not only low level of zinc, but also high levels of zinc decrease Th1 function.

Dual blockade of epidermal growth factor receptor (EGFR) and cyclooxygenase 2 (COX 2) may be dependent upon the EGFR mutational status in non-small cell lung cancer (NSCLC) cell lines

7170

Background: Recent data has shown that the benefit of EGFR TKIs (tyrosine kinase inhibitors) in NSCLC is in patients with tumors that have EGFR mutations and /or gene amplification. Even among these patients, the median survival with EGFR TKIs is only 22 months. Pre-clinical data has shown that dual blockade of EGFR and COX 2 pathways may be beneficial. A recent clinical trial conducted at our center suggested that this combination primarily impacted NSCLC tumors that have the EGFR biomarkers. We therefore hypothesized that the EGFR biomarker status determines the outcome of dual blockade of these pathways in NSCLC. Methods: Three different cell lines with varying biomarker status and sensitivities to EGFR TKIs were used- H3255 (L858R; gene amplified), H1650 (del E746-A750; gene amplified), H1781 (wild type). Cells were treated with erlotinib, EGFR TKI- 10nM-100nM or celecoxib, COX 2 inhibitor- 5 μM and with the combination of two drugs. Cell survival was determined by a standard MTT assay and apoptosis was measured by ELISA method. Western blot analysis was conducted to assess COX 2, EGFR and pAkt levels. Results: Celecoxib by itself had no effects on any of the cell lines. Erlotinib showed a concentration dependent growth inhibition of both H3255 (IC50–41.72nM; surviving fraction at 50nM was 52%) and H1650 (IC50 > 100nM; Surviving fraction at 50nM was 70%) but had no effect on H1781. Celecoxib added to erlotinib significantly enhanced the growth inhibition of H3255 (p = 0.001) and H1650 (p = 0.014) as well as apoptosis (H3255- p = 0.016; H1650- p = 0.011) at all concentrations of erlotinib but had no effect in H1781 cells. In western Blot analysis the combination significantly reduced levels of COX-2, EGFR and pAkt compared to baseline and either agent alone in H3255 cells. Conclusions: The addition of celecoxib to erlotinib has a differential effect in NSCLC cell lines based on their EGFR biomarker status. This beneficial effect of celecoxib addition may be through improved inhibition of each pathway.

[Table: see text]

DeltaNp63 expression in pancreas and pancreatic neoplasia

DeltaNp63 (DNp63) has become widely used, in particular, for distinguishing invasive carcinomas from noninvasive ducts by highlighting the myoepithelial or basal cells in the breast and prostate, respectively. It is not known whether this marker may have any application in another exocrine organ, the pancreas. As the ductal and intraductal proliferations of this organ become better characterized, the need for markers to distinguish among these processes increases. We investigated immunohistochemical expression of DNP63 in 105 cases. A total of 25 cases were non-neoplastic pancreata, 25 were pancreatic intraepithelial neoplasia (PanIN) of various grades, and 50 were examples of pancreatic ductal adenocarcinoma. Sections of non-neoplastic pancreata included various types of non-neoplastic processes such as squamous/transitional metaplasia (five cases), which can be mistaken for high-grade PanINs, as well as various degrees of reactive ductal atypia and incidental microcysts with attenuated lining (five cases). No DNp63 expression was noted in normal pancreatic ducts. On the other hand, all five foci of squamous/transitional metaplasia were strongly and uniformly positive for this marker. DNp63 labeling was also noted in those incidental microcysts lined by attenuated cells, seen amidst normal pancreatic lobules. All PanINs were negative. Among invasive carcinomas, DNp63 expression was detected only in areas of squamous differentiation and was completely absent in ordinary ductal areas. Based on this observation, five additional cases of adenosquamous/squamous carcinoma was retrieved and stained, and the squamous components of all of these were also positive. In conclusion, (I) DNp63 is a reliable marker of squamous differentiation in the pancreas. It is valuable in distinguishing squamous/transitional metaplasia from PanINs, a distinction of importance for both researchers and diagnosticians. Among invasive carcinomas, it seems to be entirely specific for areas of squamous differentiation. (II) Those incidental microcysts seen in acinar lobules and lined by attenuated cells are also positive for DNp63, which suggests that they may be metaplastic in nature, and that they do not represent neoplastic cells. (III) Unlike the ducts of other exocrine organs, breast and prostate, there are no DNp63-expressing cells in the normal pancreatic ducts, and therefore, this marker cannot be used in distinguishing invasive carcinomas from the non-invasive ducts. (IV) No p63-expressing 'stem' cells are present in the pancreas.

Pathogenesis of invasive micropapillary carcinoma: role of MUC1 glycoprotein

Invasive micropapillary carcinoma, a tumor with highly infiltrative characteristics is defined by a distinctive cleft formation around the neoplastic cell clusters which is presumably a result of the detachment of the cells from the stroma due to as yet undetermined factors. Ultrastructural examination performed on a handful of cases demonstrated an unexpected secretory activity in the stroma-facing surface of the cells. MUC1 is a glycoprotein typically expressed in the apical surface of normal epithelial cells, responsible for maintaining lumen formation. In conventional adenocarcinomas, MUC1 expression is largely intracytoplasmic, intercellular, or apical (in glandular areas). The MUC1 expression pattern was investigated by immunohistochemical staining in invasive micropapillary carcinoma of breast (n=11), pancreas (n=5), gynecologic tract (n=11) and urinary bladder (n=10). The results were contrasted with the staining pattern in conventional carcinomas of the same organs (n=202). In all invasive micropapillary carcinoma, MUC1 expression was predominantly in the stroma-facing surface of the cell clusters (basal), accentuating the outlines of the micropapillary units by forming a distinct band on this surface. In conventional carcinoma the labeling was mostly apical in areas with lumen formation and intracytoplasmic and intercellular in the poorly differentiated areas. In conclusion, in the micropapillary pattern of invasive carcinoma, the expression of MUC1, is largely limited to the basal surface of the cells in contrast to conventional carcinomas in which MUC1 is largely apical, intracytoplasmic or intercellular. This provides support for the reversal of cell orientation as an important factor of the morphogenesis and possibly the pathogenesis of invasive micropapillary carcinoma. Since MUC1 is known to have a role in lumen formation, and has an inhibitory role in the cell to stroma interaction, it is conceivable that it is a key factor in the detachment of cells from stroma allowing for the dissection of the connective tissue and easing the spread of cells.

Clinicopathological correlates of pancreatic intraepithelial neoplasia: a comparative analysis of 82 cases with and 152 cases without pancreatic ductal adenocarcinoma

Pancreatic intraepithelial neoplasia is often associated with pancreatic ductal adenocarcinoma and is presumed to be its precursor. It has been difficult to determine the frequency of these lesions because until recently, there was no consensus regarding the terminology and criteria for their grading. Here we compare the frequency and clinical correlates of pancreatic intraepithelial neoplasia in pancreata involved by ductal adenocarcinoma and in benign ones, using the criteria put forward recently. We evaluated pancreatectomy specimens from 82 patients with ductal adenocarcinoma and 152 patients who underwent pancreatectomy for reasons other than primary malignancy (trauma, pancreatitis, and metastatic tumor to pancreas) for the presence, grade, and number of foci of pancreatic intraepithelial neoplasia. Cases were graded by the highest grade of pancreatic intraepithelial neoplasia focus identified. An average of 5.3 sections of pancreas was available for evaluation (range, 1-28 sections). Overall, the frequency of pancreatic intraepithelial neoplasia lesions in ductal adenocarcinoma patients, including Grade 1A (mucinous duct lesions), was 82%, which was significantly higher than the one in benign pancreata -54%, P <.001. There was a progressive increase from normal pancreata to pancreatitis and to ductal adenocarcinoma in the frequency of overall pancreatic intraepithelial neoplasia lesions (16%, 60%, and 82%, respectively) and Grade 3 pancreatic intraepithelial neoplasia (0%, 4%, and 40%, respectively). In most instances, in any given case of higher-grade pancreatic intraepithelial neoplasia lesion, there were also several foci of lower grade lesions. The frequency of higher-grade pancreatic intraepithelial neoplasia lesions (2 and 3) in pancreata resected for ductal adenocarcinoma was 59%, significantly higher than in those without primary carcinoma (17%). This progressive increase in frequency of pancreatic intraepithelial neoplasia from incidental pancreatectomies (presumed to have a nonpathologic pancreas) to pancreatitis (considered a risk factor for carcinoma) and to ductal adenocarcinoma constitutes an indirect support for the precancerous role attributed to pancreatic intraepithelial neoplasia lesions. The relatively high absolute occurrence of pancreatic intraepithelial neoplasia Grade 1A (mucinous duct lesions) in benign conditions (43%) suggests that this group represents a combination of neoplastic and non-neoplastic lesions.

Genistein sensitizes diffuse large cell lymphoma to CHOP (cyclophosphamide, doxorubicin, vincristine, prednisone) chemotherapy

The incidence of non-Hodgkin's lymphoma (NHL) has been increasing and is now the leading cause of death in males aged 15-54. Diffuse large cell lymphoma (DLCL) is the most common subtype of NHL. These cells are notable for the high expression of the transcription factor nuclear factor kappa beta (NF-kappaB), raising the possibility that constitutive activation of the NF-kappaB pathway may contribute to the poor prognosis of DLCL patients. Soy isoflavone genistein promotes apoptosis by decreasing NF-kappaB activity. The combination of cyclophosphamide, doxorubicin, vincristine, and prednisone (CHOP) remains the standard therapy for DLCL with a cure rate of approximately 40%. The WSU-DLCL(2) cell line and its severe combined immunodeficient (SCID) xenograft have constitutively active NF-kappaB which provides us with an excellent model in which to study NF-kappaB modulation and CHOP sensitization by genistein. The antitumor activity of CHOP with or without a genistein was evaluated in our WSU-DLCL(2) model. In vivo, WSU-DLCL(2)-bearing SCID mice received genistein alone (800 micro g kg(-1) day(-1), p.o. as gavages for 5 days), CHOP alone ("C", 40 mg/kg, i.v.; "H", 3.3 mg/kg, i.v.; "O", 0.5 mg/kg, i.v.; and "P", 0.2 mg/kg, every day for 5 days, p.o.), or genistein for 5 days followed by CHOP. Tumor growth inhibition (T/C), tumor growth delay (T - C), and log(10) kill for genistein, CHOP, and genistein followed by CHOP were 33.6%, 19.2%, and 5.2%; 7, 8, and 17 days; and 1.0, 1.2, and 2.6, respectively. To begin elucidating the mechanism of genistein-induced sensitization of WSU-DLCL(2) cells to CHOP chemotherapy in this xenograft mouse model, we studied the in vitro effect of genistein on WSU-DLCL(2) growth inhibition, cell cycle, Bax:Bcl-2 ratio, NF-kappaB DNA binding, and apoptosis in vitro. At 30 micro M, genistein inhibited the growth significantly, induced G(2)-M arrest, increased Bax:Bcl-2 ratio, decreased NF-kappaB DNA binding, and induced apoptosis. Genistein also inhibited NF-kappaB DNA binding in vivo, whereas CHOP enhanced it. Our results show that genistein has growth modulatory effects on WSU-DLCL(2) cells and enhances the antitumor activity of CHOP. Because soy isoflavone genistein is a widely available nutritional supplement, its use in combination with CHOP chemotherapy should be further explored in a clinical trial in patients with NHL.

Pathogenesis of colloid (pure mucinous) carcinoma of exocrine organs: Coupling of gel-forming mucin (MUC2) production with altered cell polarity and abnormal cell-stroma interaction may be the key factor in the morphogenesis and indolent behavior of colloid carcinoma in the breast and pancreas

In the exocrine organs, breast and pancreas, colloid carcinoma (CC, pure mucinous carcinoma), characterized by well-circumscribed lakes of mucin that contain scanty, detached malignant cells, has a significantly better prognosis than conventional ductal carcinomas (DCs). It has been speculated by us and others that an inverse polarization of cells may be responsible for the accumulation of extracellular mucin. Another possibility is that this mucin is biochemically and biologically distinct from the mucin secreted by the conventional carcinomas of these organs. This study was undertaken to investigate these two hypotheses: 1) To test whether there is indeed an alteration in cell polarity in CC. Immunohistochemical stains for luminal surface glycoproteins (carcinoembryonic antigen in pancreas and MUC1 in breast) were performed in 18 pancreatic and 30 mammary CCs and compared with the expression pattern in DCs (37 pancreatic and 47 mammary) and normal ducts. The results disclosed that these glycoproteins were expressed predominantly in the stroma-facing surfaces of CC cells, in contrast to the DCs, in which the expression was either on the luminal surface (in well-differentiated areas) or dispersed throughout the cell, intracytoplasmic in the poorly differentiated areas. Ultrastructural examination performed on 10 breast and two pancreatic CCs showed the condensation of mucigen granules (generally underlying an apical-type cell membrane) in the stroma-facing surface in all cases. In contrast, in the DCs (five pancreatic and five mammary), no clustering of mucigen granules was identified in the cytoplasm facing the stroma in any of the cases. Furthermore, no external lamina or basement membrane was detected in any of the CCs, whereas in the DCs, a distinct (in 3 of 10) or discontinuous (4 of 10) external lamina separated the tumor cells from the stroma. 2) To determine the expression frequency of MUC2 in CCs and to compare it with that in DCs and normal tissue, immunohistochemical stains with MUC2 (clone ccp58) were performed. MUC2 expression was detected in 18 of 18 pancreatic and 30 of 30 breast CCs and was exceedingly rare in DCs (1 of 136 pancreatic DC and 3 of 47 mammary, p <0.0001 in both organs). No labeling was detected in normal ducts. In conclusion, it appears that coupling of two factors is important for the distinctive morphologic characteristics and slow growth of CCs: The first one is the alteration in cell orientation as evidenced by the direction of surface glycoproteins and secretory organelles to the stroma-facing surface of the cells and the disruption of cell-stroma interaction as manifested by lack of basal lamina formation. Apparently, this altered polarity allows the CC cells to secrete the mucin toward the stroma. The mucin produced, MUC2 (also called gel-forming mucin), is highly specific for CC and is known to form strong bonds with the stroma, and also was found recently to have tumor suppressor activity. This distinctive mucin, accumulated in the stroma surrounding the CC cells, may act as a containing factor, slackening the spread of the cells.

The dichotomy in the preinvasive neoplasia to invasive carcinoma sequence in the pancreas: differential expression of MUC1 and MUC2 supports the existence of two separate pathways of carcinogenesis

Emerging evidence suggests a dichotomy in the dysplasia-CIS-invasive carcinoma sequence in the pancreas. Pancreatic intraepithelial neoplasms (PanINs; small, incidental duct lesions) progress to invasive ductal adenocarcinomas (5-y survival of < 15%), whereas intraductal papillary mucinous neoplasms (large, intraductal tumors with ductal dilatation) are often associated with colloid carcinoma (5-y survival of > 55%). We explored the relationship of these lesions by examining the expression of MUC1 and MUC2, glycoproteins reportedly reflecting "aggressive" and "indolent" phenotypes in pancreas cancer, respectively. Immunohistochemical labeling with MUC1 (clone Ma695) and MUC2 (clone Ccp58) antibodies was performed on PanINs (n = 43), intraductal papillary mucinous neoplasms (n = 74), ductal adenocarcinomas (n = 136), and colloid carcinomas (n = 15). Fifty-four percent of the intraductal papillary mucinous neoplasms expressed MUC2, whereas none of the PanINs did. In contrast, PanINs, especially higher grade lesions, were often positive for MUC1 (61% of PanIN 3), whereas the expression of this glycoprotein was infrequent in intraductal papillary mucinous neoplasms (20%). This dichotomy was further accentuated in the invasive carcinomas with which these two preinvasive pathways are respectively associated: all colloid carcinomas were MUC2+ (100%) and MUC1- (0%), whereas the labeling pattern was the reverse for ductal adenocarcinomas: 63% were MUC1+ and only 1% were MUC2+. These results support a dichotomy in the dysplasia-CIS sequence in the pancreas. Because these two pathways often lead to different types of invasive carcinomas, this is an invaluable model for the study of carcinogenesis. The findings here also support the previous impression that MUC2 (the mucin associated with gel formation) is a marker of the "indolent" pathway (intraductal papillary mucinous neoplasm and colloid carcinoma), whereas MUC1 (the glycoprotein known to have an inhibitory role in cell-cell and cell-stroma interactions as well as in immunoresistance of tumor cells) is a marker of the "aggressive" pathway (PanIN to ductal adenocarcinoma).

Expression of inflammatory modulator COX-2 in pancreatic ductal adenocarcinoma and its relationship to pathologic and clinical parameters

Despite the exceedingly poor prognosis of pancreatic cancer, it is often histologically well to moderately differentiated. The apparent resistance to conventional therapeutic modalities is poorly understood and may be related to the molecules involved in its progression or its propensity for perineurial invasion. Cyclooxygenase-2 (COX-2) is an inducible enzyme homologous to COX-1 that is responsible for production of prostaglandins at sites of inflammation. It is activated by a variety of growth factors and tumor promoters, and it has been implicated in cancer progression. It may also have a role in the resistance to therapy. Anti-COX-2 agents have been documented to have antitumor activity, and some are now being tested in the therapy for various cancers, including those of the pancreas. Experience regarding the rate of COX-2 expression in pancreatic cancer and its relationship to the clinical and biologic parameters is very limited. In this study, immunohistochemical stains for COX-2 have been performed on 120 cases of pancreatic ductal adenocarcinoma. The stains were scored according to the percentage (0: no staining, 1: < 10%, 2: 10-50%, and 3: >50% of the cells staining) and intensity (0 for no staining, 1 for mild staining, and 2 for dark staining) of staining. Based on the combined score for each case, they were divided into low expressors (percentage and intensity < or =1) and high expressors (percentage or intensity >1). In addition to global scoring for each case, the glandular and solid (poorly differentiated) components, when present, were scored separately. The global scores were correlated with clinical and biologic parameters. Seventy-four percent of the cases exhibited expression of COX-2 and 53% were high expressors. No significant association was observed when comparing the global COX-2 expression to survival, tumor size, stage, and vascular invasion. Increased perineural invasion was found to be significantly associated with COX-2 expression (p < 0.05). Increased expression was also more common in the glandular component as compared with the solid component of the tumors (68% versus 35%, p < 0.05). Of the 34 patients who received radiotherapy, 9 were low expressor (median survival 19.5 months) and 25 were high expressors (median survival 14 months). The difference in survival was not statistically significant.

Colloid (mucinous noncystic) carcinoma of the pancreas

In the past, colloid (mucinous noncystic) carcinoma (CC) of the pancreas had been included under the category of ordinary ductal adenocarcinoma, a tumor with a dismal prognosis, or was frequently misdiagnosed as mucinous cystadenocarcinoma. The clinicopathologic features of CC have not yet been well characterized, because most cases on record have been parts of studies on either mucinous cystic neoplasms (MCN) or intraductal papillary mucinous neoplasms (IPMN), with which colloid carcinomas are frequently associated. To determine the clinicopathologic characteristics of CC, 17 pancreatic tumors composed predominantly (>80%) of CC (defined as nodular extracellular mucin lakes with scanty malignant epithelial cells) and in which the invasive carcinoma measured larger than 1 cm were studied. Ten of these were originally classified as mucinous ductal adenocarcinoma and four as mucinous cystadenocarcinoma. The mean age of the patients was 61 years; 9 were men and 8 were women. The mean size of the CC was 5.3 cm (range, 1.2-16 cm). In more than half of the patients, CC represented the invasive component of an IPMN (in nine cases) or MCN (in one case). The tumors were composed of well-defined pools of mucin with sparse malignant cells in various patterns of distribution. Signet-ring cells floating in the mucin (but not as individual cells infiltrating stroma, a characteristic finding of signet-ring cell adenocarcinomas) were commonly identified and were prominent in five cases. Perineurial invasion was noted in six cases and regional lymph node metastases in eight. Mutation in codon 12 of the k-ras gene was detected in only 4 of 12 cases studied and p53 mutation in 2 of 9. Immunohistochemical and histochemical mucin stains suggested luminalization of the basal aspects of the cells. Five-year survival was 57%. At an overall mean follow up of 57 months, 10 patients were alive with no evidence of disease (median, 79 mos), including four with lymph node metastasis, three others with perineurial invasion, and another with vascular invasion. Four patients died of disease (18, 18, 25, and 26 mos), and three died of thromboembolism (with persistent disease) at 2, 5, 10 months. All seven patients who died with or of tumor had undergone incisional biopsy of the tumor either before the operation or intraoperatively, whereas none of the patients who were alive had incisional biopsy. When compared with 82 cases of resectable ordinary ductal adenocarcinoma on whom follow-up and staging information was complete, it was found that the patients with CC present with larger tumors (p = 0.03) but lower stage (p = 0.01). The prognosis of CC is significantly better: 2-year and 5-year survival are 70% versus 28% and 57% versus 12%, respectively (p = 0.001). In conclusion, pancreatic CC may occur with or without an identifiable IPMN and MCN component, and should be distinguished from mucinous cystadenocarcinoma, ordinary ductal adenocarcinoma, and signet-ring cell adenocarcinoma. CC of the pancreas is associated with a significantly better prognosis than ordinary ductal adenocarcinoma. In addition to its distinctive morphologic and clinical characteristics, CC of the pancreas also appears to have a low incidence of mutation in codon 12 of the k-ras gene. In cases with a clinical suspicion of colloid carcinoma, the possibility that an incisional biopsy may contribute to thromboembolic complications or even dissemination of the tumor may need to be considered. The luminalization of the basal aspects of the tumor cells may be the cause of stromal mucin accumulation that characterizes colloid carcinoma and may act as a containing factor.