|ognizant Communication Corporation|
Featuring PRECLINICAL AND CLINICAL CANCER THERAPEUTICS
VOLUME 18, NUMBERS 5/6
Oncology Research, Vol. 18, pp. 193-201
0965-0407/09 $90.00 + .00
Copyright © 2009 Cognizant Comm. Corp.
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Evaluation of Molecular Markers in Canine Mammary Tumors: Correlation With Histological Grading
G. Vinothini,1 C. Balachandran,2 and S. Nagini1
1Department of Biochemistry and Biotechnology, Faculty of
Science, Annamalai University, Tamil Nadu, India
2Department of Veterinary Pathology, Madras Veterinary College, Tamil Nadu, India
The objective of this study was to evaluate molecular markers involved in mammary tumorigenesis in a canine model that mimics many essential elements of human breast cancer. Thirty mammary gland tumors and control tissues obtained from female dogs were included in the study. We analyzed changes in the expression of markers of hormone and receptor status (estradiol, estrogen receptor; ER and HER-2/neu), hormone metabolism (CYP1A1 and CYP1B1), cell proliferation and survival [proliferating cell nuclear antigen (PCNA), glutathione S-transferase-P (GST-P), nuclear factor-kB (NF-kB-p50, NF-kB-p65), phosphorylated-inhibitor of kB-a (p-IkB-a) and IkB], apoptosis (Bcl-2, Bax, caspases, Apaf-1, cytochrome-C, and PARP), invasion [matrix metalloproteinases-2 and -9 (MMP-2, MMP-9), tissue inhibitor of matrix metalloproteinase-2 (TIMP-2), and reversion-inducing cysteine-rich protein with Kazal motifs (RECK)], angiogenesis [vascular endothelial growth factor (VEGF)], and epigenetics [DNA methyltransferase (Dnmt-1), histone deacetylase (HDAC-1)] by immunohistochemical localization and Western blot analysis and correlated these with histological grade. The present study provides evidence that increased expression of ER, HER-2/neu, estradiol, and its metabolizing enzymes, as well as proteins involved in cell proliferation, apoptosis evasion, invasion, and angiogenesis may confer a selective growth advantage to canine mammary tumors. To our knowledge this is the first report on the hallmark capabilities of canine mammary tumors, which lends credence to the view that the dog is a valuable model for human breast cancer studies.
Key words: Apoptosis; Breast cancer; Canine mammary tumors; Estradiol
Address correspondence to Dr. S. Nagini, Professor, Department of Biochemistry and Biotechnology, Faculty of Science, Annamalai University, Annamalainagar-608 002, Tamil Nadu, India. Tel: +91-4144-239842; Fax: +91-4144-238145/238080; E-mail: email@example.com or firstname.lastname@example.org
Inhibition of TC-1 Tumor Progression by Cotransfection of Saxatilin and IL-12 Genes Mediated by Lipofection or Electroporation
Y. S. Park,1 K. S. Kim,2 Y. K. Lee,1 J. S. Kim,1 J. Y. Baek,1 and L. Huang3
1Department of Biomedical Laboratory Science, Yonsei University,
Wonju 220-710, Republic of Korea
2Department of Biomedical Sciences, Youngdong University, Chungbuk 370-701, Republic of Korea
3Division of Molecular Pharmaceutics, University of North Carolina School of Pharmacy, Chapel Hill, NC, USA
Recently, a number of reports have demonstrated that coexpression of therapeutic genes having different anticancer mechanisms is a more effective strategy for anticancer gene therapy than single gene expression. Saxatilin, a novel disintegrin from snake venom, has recently been shown to have potent antiangiogenic functions, such as inhibition of platelet aggregation, bFGF-induced proliferation of HUVEC, and vitronectininduced smooth muscle cell migration. IL-12 is a well-known immune modulator that promotes Th1-type antitumor immune responses and inhibits angiogenesis as well. The saxatilin and/or IL-12 genes were transfected intratumorally into C57BL/6 mice carrying TC-1 transformed mouse lung endothelial cells by either lipofection or electroporation. The plasmids encoding saxatilin and IL-12 were administered to tumor tissues via novel cationic liposomes consisting of dimyristyl-glutamyl-lysine (DMKE). On the other hand, expression of the genes was also induced by electroporation after naked pDNA injection to the tumor tissues. Lipofection of saxatilin and/or IL-12 genes appeared to be slightly more effective in inhibition of tumor growth than electroporation of the same genes. Cotransfection of saxatilin and IL-12 genes was clearly more effective than individual administration of either gene. This result implies that cotransfection of saxatilin and IL-12 genes represents an innovative modality for anticancer gene therapy.
Key words: TC-1 cancer cells; Saxatilin; IL-12; Inhibition of tumor progression
Address correspondence to Yong Serk Park, Ph.D., Department of Biomedical Laboratory Science, Yonsei University, Wonju, Gangwon 220-710, Republic of Korea. Tel: +82-371-760-2448; Fax: +82-371-763-5224; E-mail: email@example.com
Changes of Telomerase Activity by Alternative Splicing of Full-Length and b Variants of hTERT in Breast Cancer Patients
Sun Young Rha,1,2 Hei Cheul Jeung,1,2 Kyu Hyun Park,1 Jin Ju Kim,3 and Hyun Cheol Chung1,2
1Cancer Metastasis Research Center, Yonsei Cancer Center,
Yonsei University College of Medicine, Seoul, Korea
2Department of Internal Medicine, Yonsei University College of Medicine, Seoul, Korea
3Department of Laboratory Medicine, Inha University School of Medicine, Incheon, Korea
Human telomerase reverse transcriptase (hTERT) expression level may not always correlate with telomerase activity. Although the positions of the spliced sites suggest that many of the variants do not code for functional reverse transcriptase, the functions of the spliced variants of hTERT are unknown. We analyzed hTERT splicing patterns with respect to telomerase activity in breast cancer. We examined telomerase activity by telomeric repeat amplification protocol (TRAP) assay and detected spliced variants of hTERT by reverse transcription-polymerase chain reaction (RT-PCR). Of 45 breast cancer patients, 38 (84%) were found to express telomerase activity and 41 (91%) expressed hTERT. In patients with telomerase activity, 14 (37%) expressed all four types of variants (full length, a, b, and a/b). Eleven patients (29%) expressed both the full-length and b variant. Eight patients (22%) expressed the b variant only and 3 (8%) expressed the full-length type only. When comparing telomerase activity to the expression of splicing variants, a tendency was found for lower telomerase activity in patients expressing the b variant only (45 ± 11) versus those expressing all four types (64 ± 32) and those coexpressing the full-length type with the b variant (61 ± 22) (p = 0.06, respectively). In patients with both full-length and b variants coexpression, increment of b variant showed a decreased telomerase activity regardless of the full-length variant expression (p = 0.027). Telomerase activity changed with alternative splicing of the full-length and b variants expression of hTERT in breast cancer.
Key words: Alternative splicing; hTERT; Breast cancer; Full-length; b variant
Address correspondence to Hyun Cheol Chung, M.D., Ph.D., 134 Shinchon-dong, Seodaemun-gu, Cancer Metastasis Research Center, Yonsei Cancer Center, Yonsei University College of Medicine, 120-752 Seoul, Korea. Tel: 82-2-2228-8132; Fax: 82-2-393-3652; Ee-mail: firstname.lastname@example.org
ATP Depletion as a Consequence of Hypoxia Enhances Tamoxifen Antiproliferative Effects in T47D Breast Carcinoma Cells
M. Seyedabadi,1 M. H. Ghahremani,2 and S. N. Ostad2
1Department of Pharmacology, School of Medicine, Tehran University
of Medical Sciences, Tehran, Iran
2Department of Toxicology and Pharmacology, School of Pharmacy, Tehran University of Medical Sciences, Tehran, Iran
Tamoxifen causes a mitochondrial transmembrane potential dysfunction and ATP depletion, which may play a role in tamoxifen cytotoxicity. Administration of oligomycin-2 deoxy glucose (2DG) enhanced tamoxifen antiproliferative effects, which may be due to exacerbated ATP depletion following tamoxifen and oligomycin-2DG coadministration. Sodium nitroprusside (SNP) did not significantly change tamoxifen responsiveness at 0.1, 0.5, and 1 mM; however, 2 mM SNP hampered tamoxifen effects on cell proliferation and cell cycle. Oligomycin-2DG neither changed iNOS expression nor altered its attenuated expression due to tamoxifen exposure, suggesting that ATP depletion-mediated sensitivity to tamoxifen seems to be apart from iNOS.
Key words: Chemical hypoxia; T47D; Tamoxifen; Breast cancer; Nitric oxide synthase
Address correspondence to Professor S. N. Ostad, Department of Toxicology and Pharmacology, Tehran University of Medical Sciences, P.O. Box 14155/6451, Tehran, Iran. E-mail: email@example.com
Targeting of Multiple Signaling Pathways by the Hsp90 Inhibitor SNX-2112 in EGFR Resistance Models as a Single Agent or in Combination With Erlotinib
John W. Rice, James M. Veal, Amy Barabasz, Briana Foley, Patrick Fadden, Anisa Scott, Ken Huang, Paul Steed, and Steven Hall
Serenex, Inc., Durham, NC, USA
Inhibition of Hsp90 has emerged as a therapeutic strategy to target NSCLC subtypes, which are refractory to epidermal growth factor receptor (EGFR) inhibitor-based treatment. We report on a novel small molecule inhibitor of Hsp90, SNX-2112, and an orally bioavailable prodrug analog, SNX-5422. In cellular models of wild-type or mutant EGFR (L858R and T790M mutations), SNX-2112 alone and in combination with erlotinib inhibited EGF activation of pAKT,(473) and pSTAT3(705). pERK1/2 and pS6 were also potently inhibited by similar treatments. SNX-2112 reduced EGF cross-talk and activation of the c-Met receptor by causing c-Met degradation. In NCI-H1975 xenograft models, SNX-5422 showed activity as a single agent and in combination with erlotinib resulted in prolonged animal survival at reduced compound concentrations relative to either compound alone. These results support the advanced evaluation of SNX-5422 as a treatment for non-small cell lung cancer (NSCLC), especially in cases where the cancer is driven by c-Met amplification or mutated EGFR forms that are resistant to EGFR inhibitors.
Key words: Hsp90; SNX-2112; Non-small cell lung cancer (NSCLC); Erlotinib; Epidermal growth factor receptor (EGFR)
Address correspondence to John W. Rice, Pamlico Pharmaceuticals, Inc., PO Box 110284, Research Triangle Park, NC 27709, USA. Tel: 919-313-9661; E-mail: firstname.lastname@example.org
Na+-Stimulated Na+/H+ Exchange and an Unfavorable Ca2+ Homeostasis Initiate the Cycloxygenase-2 Inhibitors-Induced Apoptotic Signals in Colonic Epithelial Cells During the Early Stage of Colon Carcinogenesis
Shailender Singh Kanwar,1* Karnati R. Roy,2** Bimla Nehru,1 Pallu Reddanna,2 and Sankar Nath Sanyal1
1Department of Biophysics, Panjab University, Chandigarh,
2Department of Animal Sciences, School of Life Sciences, University of Hyderabad, Hyderabad, India
Evidence suggests that nonsteroidal anti-inflammatory drugs (NSAIDs) inhibit cycloxygenase (COX) and production of the proinflammatory prostaglandin, PGE2, and thus prevent carcinogenesis in the colon. Indeed, one of the specific COX-2 inhibitors, celecoxib, had been accepted by the US FDA for the treatment of familial adenomatous polyposis. However, the molecular mechanism of such inhibition is not clear, although apoptosis appears to be the dominant antiproliferative end effect. The present study delineates the intracellular ionic milieu in the colonocytes that could generate strong apoptotic signals where DMH-induced carcinogenesis was studied in the initiation stage in rats and its regression with the COX inhibitors. While DMH treatment produced a significant elevation in the Na+/H+ exchanger activity and resultant proton efflux, this was reversed by the NSAIDs, particularly so with celecoxib and etoricoxib compared to aspirin. Similarly, the intracellular pH was changed, with more alkalosis noted in DMH, which was reversed by NSAIDs. Also, an intracellular Ca2+ build up was noted by Fura 2 AM, which was also supported by a reduced Ca2+ ATPase and an enhanced inward movement of Ca22+. Further, mitochondrial dysfunction-related cyt C release, increased DNA ladder formation, activation of caspase-3, and cleavage product of poly (ADP-ribose) polymerase (PARP) were not seen in DMH but well noted in NSAIDs. Our results indicate that NSAIDs can induce apoptosis through a change in the colonic Na+/H+ exchange, intracellular pH, and an unfavorable Ca2+ homeostasis.
Key words: Colon carcinogenesis; Na+/Hs+ exchange; Intracellular pH; Ca2+ homeostasis; Apoptosis
Address correspondence to Prof Sankar N. Sanyal, Department of Biophysics, Panjab University, Chandigarh, 160 014, India. Tel: +91-172-2534122; E-mail: email@example.com
*Presently at John D. Dingell VA Medical Center, Department of Internal
Medicine, School of Medicine, Wayne State University, Detroit, MI 48201,
**Presently at Department of Cell Biology, University of Virginia, Charlottesville, VA 22903, USA.
Anticancer Activity and Apoptotic Effects of Bulnesia sarmienti Against Human Lung Cancer H460 Cells
Mohammad Lalmoddin Mollah,1 Jae-Chan Song,1 Chang-Ho Park,2 Gee-Dong Lee,2 Joo-Heon Hong,2 Zae Young Ryoo,3 Sanggyu Lee,3 Kyu-Tae Chang,4 and Kil-Soo Kim1
1College of Veterinary Medicine, Kyungpook National University,
Daegu, Republic of Korea
2Daegu Bio Industry Center, Daegu, Republic of Korea
3College of Natural Sciences, Kyungpook National University, Daegu, Republic of Korea
4National Primate Research Center, Korea Research Institute of Bioscience and Biotechnology, Ochangmyeon, Chungbuk, Republic of Korea
Bulnesia sarmienti (BS), a traditional South American herbal medicine native to Gran Chaco, has been used to treat various human ailments. The effects of BS aqueous extract (100, 200, and 400 mg/ml) on H460 cell lines were investigated. High-performance liquid chromatography (HPLC) confirmed that BS contains catechins as major compound. 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay, cell cycle analysis, DNA fragmentation, apoptosis, and immunoblot analysis on cells were carried out. BS has strong cytotoxic activity on the H460 cell lines (IC50; less than 100 mg/ml) in MTT assay. Flow cytometry indicated that BS arrested the cell cycle in the sub-G1 phase. When BS was treated on H460 cells, DNA fragmentation was increased, and early apoptotic cells were shown to be positive by annexin V staining. Also, the expressions of the p53 and Bax were increased and Bcl-2 protein was downregulated with BS treatment. These results indicated that the BS has anticancer activity on H460 cells and BS may be useful in future therapeutic applications for developing anticancer agents.
Key words: Bulnesia sarmienti; Cytotoxicity; Anticancer; Apoptosis; H460 cells
Address correspondence to Dr. Kil-Soo Kim, Department of Veterinary Toxicology, College of Veterinary Medicine, Kyungpook National University, Daegu, 702-701, Republic of Korea. Tel: +82 53 950 7792; Fax: +82 53 950 5955; E-mail: firstname.lastname@example.org
Role of the Adiponectin Leptin Ratio in Prostate Cancer
Michael E. Grossmann,1 Nancy K. Mizuno,1 Melissa J. L. Bonorden,1 Amitabha Ray,1 Irina Sokolchik,2 Meena L. Narasimhan,2 and Margot P. Cleary1
1Hormel Institute, University of Minnesota, Austin, MN, USA
2Bindley Bioscience Center, Purdue University, West Lafayette, IN, USA
We hypothesize that adiponectin and leptin may be capable of mediating some of the effects that body weight has on prostate cancer and that a mouse model may be effective to examine this hypothesis. We found that tumors from the TRAMP prostate cancer model expressed adiponectin and leptin receptors. TRAMP-C2 prostate cancer cell proliferation was reduced by adiponectin. Leptin was able to block the ability of adiponectin to reduce cell proliferation through altered signaling of the ERK pathway. Overall, this work suggests that adiponectin, leptin, and their receptors may play an important role in prostate cancer.
Key words: Prostate cancer; TRAMP mice; TRAMP-C2 cells; Adiponectin; Leptin; Osmotin
Address correspondence to Margot P. Cleary, Ph.D., Hormel Institute, University of Minnesota, 801 16th Avenue NE, Austin, MN 55912, USA. Tel: 507-437-9655; Fax: 507-437-9606; E-mail: email@example.com
Prognostic Factors in Women With Early Stage Small Cell Carcinoma of the Uterine Cervix
Chao-Yuan Huang,1,2 Yu-Li Chen,3 Tieh-Chi Chu,2,4 Wen-Fang Cheng,3,5 Chang-Yao Hsieh,3 and Ming-Chieh Lin6
1Division of Radiation Oncology, Department of Oncology,
National Taiwan University Hospital and National Taiwan University College
of Medicine, Taipei 10002, Taiwan
2Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, Hsinchu 30013, Taiwan
3Department of Obstetrics and Gynecology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei 10002, Taiwan
4Department of Radiological Technology, Yuanpei University, Hsinchu 30015, Taiwan
5Department of Medical Research, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei 10002, Taiwan
6Department of Pathology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei 10002, Taiwan
Small cell carcinoma of the uterine cervix (SCCUC) is an uncommon, aggressive disease accounting for less than 5% of all cervical cancers. Due to its rarity, definitive treatment strategies have not been developed. Our aim was to analyze the clinical factors, treatment modalities, sites of relapse, and overall survival of women with early stage SCCUC and thus determine prognostic factors. The clinical records of 18 women diagnosed with stage IB1 to IIA SCCUC were reviewed, and patient characteristics and treatment modalities were analyzed to determine the prognostic factors for disease-free survival (DFS) and overall survival (OS). DFS and OS were 39% and 44% at 2 years. Lymph node metastasis was a significant prognostic factor of DFS. International Federation of Gynecology and Obstetrics (FIGO) stage and lymph node metastasis were significant prognostic factors of OS as determined by multivariate analysis (p < 0.05). Radical hysterectomy followed by adjuvant chemotherapy resulted in higher 2-year survival rates compared to radical hysterectomy followed by adjuvant radiotherapy (62.5% vs. 16.7%); however, the difference was not statistically significant due to the small sample size. FIGO stage and lymph node metastasis are significant indicators of OS in patients with early stage SCCUC. Further larger scale analysis is warranted to determine whether adjuvant chemotherapy may facilitate a better prognosis than adjuvant radiotherapy.
Key words: Adjuvant therapy; Disease-free survival; FIGO stage; Overall survival; Small cell carcinoma; Uterine cervix
Address correspondence to Dr. Chao-Yuan Huang, Division of Radiation Oncology, Department of Oncology, National Taiwan University Hospital and National Taiwan University College of Medicine, Taipei 10002, Taiwan. Tel: 886-2-2312-3456, ext. 67635; Fax: 886-2-2331-2172; E-mail: firstname.lastname@example.org
Dynamic CD8 T-Cell Responses to Tumor-Associated Epstein-Barr Virus Antigens in Patients With Epstein-Barr Virus-Negative Hodgkin's Disease
Holbrook Kohrt,1,2* Alexandre Johannsen,1* Richard Hoppe,3 Sandra J. Horning,2 Saul A. Rosenberg,2 Ranjana Advani,2 and Peter P. Lee1
1Division of Hematology, Stanford University School of Medicine,
Stanford, CA, USA
2Division of Oncology, Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA
3Department of Radiation Oncology, Stanford University School of Medicine, Stanford, CA, USA
In almost half of patients diagnosed with Hodgkin's disease (HD), the malignant Reed-Sternberg (RS) cells express Epstein-Barr virus (EBV) antigens. Multiple translational efforts are actively investigating antitumor immune strategies by stimulating cytotoxic T lymphocytes (CTL) against tumor-associated EBV antigens. It has previously been believed that this therapeutic strategy and presence of EBV-specific CTLs are limited to EBV-positive HD. In an effort to explore the EBV-specific immune response, here we characterize EBV-specific CTL responses to lytic and latent EBV antigens in 12 consecutive EBV carriers with EBV-negative HD. Compared to healthy donors, we detected weak, baseline EBV-specific responses to both lytic and latent antigens by IFN-gELISPOT in patients with EBV-negative HD at diagnosis. Chemoradiotherapy was associated temporally with a decrease EBV-specific responses. At final follow-up (24 months), recovery of EBV-specific CTL responses was observed with robustness of lytic-specific response equivalent to healthy controls. We confirm evidence of EBV-specific CTLs in patients with EBV-negative HD and provide the first report of dynamic variance in this population during treatment. Our observation challenges prior belief that patients with HD remain immunodeficient following therapy and argues that the clinical significance of the EBV-specific immune response in EBV-negative HD should be further investigated.
Key words: Epstein-Barr virus; Hodgkin's disease; Lymphocyte; Immune response
Address correspondence to Peter P. Lee, M.D., CCSR Room 1155, 269 Campus Drive, Stanford, CA 94305, USA. Tel: 650-498-7942; Fax: 650-736-0974; E-mail: email@example.com or Ranjana H. Advani, M.D., Stanford Cancer Center, 875 Blake Wilbur Drive, MC5151, Stanford, CA 94305, USA. Tel: 650-724-8372; Fax: 650-724-5203; E-mail: firstname.lastname@example.org
*Authors contributed equally to this work.