ognizant Communication Corporation

ONCOLOGY RESEARCH
AN INTERNATIONAL JOURNAL
INCORPORATING ANTI-CANCER DRUG DESIGN

ABSTRACTS
VOLUME 16, NUMBER 2

Oncology Research, Vol. 16, pp. 57-65
0965-0407/06 $90.00 + .00
E-ISSN 1555-3906
Copyright © 2006 Cognizant Comm. Corp.
Printed in the USA. All rights reserved.

Demonstration of Inter- and Intracellular Distribution of Boron and Gadolinium Using Micro-Proton-Induced X-Ray Emission (Micro-PIXE)

K. Endo,1 T. Yamamoto,1 Y. Shibata,1 K. Tsuboi,1 A. Matsumura,1 H. Kumada,2 K. Yamamoto,2 T. Sakai,3 T. Sato,3 M. Oikawa,3 Y. Ohara,3 and K. Ishii4

1Department of Neurosurgery, Institute of Clinical Medicine, University of Tsukuba, Ibaraki, Japan
2Department of Research Reactor, Japan Atomic Energy Agency (JAEA), Ibaraki, Japan
3Advanced Radiation Technology Center, Japan Atomic Energy Agency (JAEA), Ibaraki, Japan
4School of Engineering, Tohoku University, Sendai, Japan

Micro-proton-induced X-ray emission (Micro-PIXE) was applied to determine inter- and intracellular distribution of boron (10B) and gadolinium (157Gd), the capture atoms used to kill tumor cells in neutron capture therapy (NCT). Cultured 9L gliosarcoma cells on Mylar film were exposed to sodium borocaptate (BSH) and gadobenate dimeglumine (Gd-BOPTA). To analyze the inter- and intracellular distribution of 10B and 157Gd in 9L gliosarcoma cells, the cells were irradiated using a proton beam of 1.7 or 3 MeV energy collimated to 1 mm diameter and emission X-ray was detected. The distribution of  10B and 157Gd in 9L gliosarcoma cells was then examined. In this study, we could directly analyze the inter- and intracellular distribution of 10B and 157Gd elements in 9L gliosarcoma cells directly using Micro-PIXE. This is the first report on the distribution of 10B employing a method to detect g-rays resulting from the nuclear reaction of 10B using particle-induced g-ray emission (PIGE). These results show that the distribution of 157Gd elements was correctly measured using micro-PIXE. 157Gd should have the same tendency as 10B in cultured 9L gliosarcoma cells and agree with the distribution in 9L gliosarcoma cells. Further investigation is necessary for a higher spatial resolution and optimization of the measurement time or improvement of the sampling method. In the future, it will be possible to employ this method to analyze the intracellular microdistribution of the capture element and in the development of new drugs for NCT.

Key words: Micro-PIXE; Inter- and intracellular distribution; Boron-10 10B); Gandolinium-157 (157Gd); Boron neutron capture therapy (BNCT)

Address correspondence to Kiyoshi Endo, Department of Neurosurgery, Institute of Clinical Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba-shi, Ibaraki 305-8575, Japan. Tel: +81-29-853-3220; Fax: +81-29-853-3214; E-mail: neuro-2@hata-hp.or.jp




Oncology Research, Vol. 16, pp. 67-74
0965-0407/06 $90.00 + .00
E-ISSN 1555-3906
Copyright © 2006 Cognizant Comm. Corp.
Printed in the USA. All rights reserved.

Quercetin Induces p53-Independent Apoptosis in Human Prostate Cancer Cells by Modulating Bcl-2-Related Proteins: A Possible Mediation by IGFBP-3

Marati R. Vijayababu,1 P. Kanagaraj,1 A. Arunkumar,1 R. Ilangovan,1 A. Dharmarajan,2 and J. Arunakaran1

1Department of Endocrinology, Dr. ALM Postgraduate Institute of Basic Medical Sciences, University of Madras, Taramani Campus, Chennai-600 113, India
2School of Anatomy and Human Biology, The University of Western Australia, Crawley, Western Australia 6009, Australia

Quercetin, a flavonoid found in onion, grapes, green vegetables, etc., has been shown to possess potent antiproliferative effects against various malignant cells. We report insulin-like growth factor-binding protein-3 (IGFBP-3) as an effector of quercetin-induced apoptosis in human prostate cancer cell lines in a p53-independent manner. We evaluated the production of IGFBP-3 in quercetin-treated cells. Apoptosis was studied in quercetin-treated cells to study the IGFBP-3-mediated role with flow cytometry and DNA fragmentation. Protein expressions of Bcl-2, Bcl-xL, and Bax were studied by Western blot. Increased production of IGFBP-3 was associated with the increased ratio of proapoptotic to antiapoptotic members of the Bcl-2 family. In quercetin-treated PC-3 cells, an increase in Bax protein expression and a decrease in Bcl-xL protein and Bcl-2 protein were observed. As PC-3 is a p53-negative cell line, these modulations of proapoptotic proteins and induction of apoptosis were independent of p53. The level of IGFBP-3 on the response of PC-3 cells to quercetin was examined. There was a twofold increase in IGFBP-3 level in conditioned media of 100 mM quercetin-treated cells. Quercetin also brought a peak at sub-G1 in PC-3 cells. Thus, increased level of IGFBP-3 was associated with increased proapoptotic proteins and apoptosis in response to quercetin, suggesting it may be a p53-independent effector of apoptosis in prostate cancer cells via its modulation of the Bax/Bcl-2 protein ratio.

Key words: Quercetin; Insulin-like growth factor binding protein-3 (IGFBP-3); Bcl-2 protein; Apoptosis

Address correspondence to J. Arunakaran, Department of Endocrinology, Dr. ALM Postgraduate Institute of Basic Medical Sciences, University of Madras, Taramani Campus, Chennai-600 113, India. E-mail: j_arunakaran@hotmail.com




Oncology Research, Vol. 16, pp. 75-84
0965-0407/06 $90.00 + .00
E-ISSN 1555-3906
Copyright © 2006 Cognizant Comm. Corp.
Printed in the USA. All rights reserved.

Different Forms of Prolactin Have Opposing Effects on the Expression of Cell Cycle Regulatory Proteins in Differentiated Mammary Epithelial Cells

Wei Wu,1 Yen-Hao Chen,1 Eric Ueda,1,2 Dunyong Tan,1 Paolo Bartolini,2 and Ameae M. Walker1

1Division of Biomedical Sciences, University of California, Riverside, CA 92521-0121, USA
2IPEN-CNEN, Universidade de São Paulo, Brasil

Prolactin (PRL) is a hormone that contributes to both the growth and differentiation of mammary epithelial cells, activities likely to impact breast cancer in opposite ways. Whether PRL causes growth or differentiation has been solely attributed to the coexisting steroidal environment, with PRL stimulating mammary gland growth during pregnancy, and then milk production after the postpartum drop in estrogen and progesterone. However, previous work from our laboratory has shown that the form of PRL may also be an important factor. During pregnancy, unmodified PRL (U-PRL) promotes mammary growth, while an increase in phosphorylated PRL, or administration of a molecular mimic of phosphorylated PRL (S179D PRL), inhibits growth. Unknown, however, is whether these forms of PRL have opposite effects on growth in the absence of steroids and whether effects are directly on mammary epithelial cells. To mimic the glandular epithelium in vitro, we used contact-inhibited, differentiated cells and showed that even with these minimally growing cells that treatment with U-PRL caused increased expression of cyclin D1 and cyclin-dependent kinase 4, increased activity of both cdk4 and cdk2, while having no effect on the inhibitory protein, p21. S179D PRL, by contrast, had no effect on cyclin D1 and cdk4 expression, but increased p21 expression and expression of the vitamin D receptor (VDR). We conclude that increased U-PRL or decreased phosphorylated PRL can directly affect cell cycle control proteins in relatively differentiated mammary epithelial cells, thereby implicating the balance between these two forms of PRL in the early promotion of breast cancer.

Key words: Cell cycle regulatory proteins; Cyclin D; Cyclin-dependent kinases 2 and 4; MAP kinase; p21; Phosphorylated prolactin; Prolactin; 1,25 Dihydroxy vitamin D3; Vitamin D receptor

Address correspondence to Ameae M. Walker, Division of Biomedical Sciences, University of California, Riverside, CA 92521-0121, USA. Tel: (951) 827-5942; Fax: (951) 827-5504; E-mail: ameae.walker@ucr.edu




Oncology Research, Vol. 16, pp. 85-95
0965-0407/06 $90.00 + .00
E-ISSN 1555-3906
Copyright © 2006 Cognizant Comm. Corp.
Printed in the USA. All rights reserved.

Schedule-Dependent Interactions Between Pemetrexed and Cisplatin in Human Carcinoma Cell Lines In Vitro

Yasuhiko Kano,1 Miyuki Akutsu,1 Saburo Tsunoda,1 Tohru Izumi,1 Hiroyuki Kobayashi,1 Koichi Inoue,2 Kiyoshi Mori,3 Hirofumi Fujii,3 Hiroyuki Mano,4 Tsogbadrakh Odgerel,5 and Yusuke Furukawa5

1Division of Hematology, Tochigi Cancer Center, 4-9-13, Yonan, Utsunomiya, Tochigi, 320-0834, Japan
2Division of Radiation Oncology, Tochigi Cancer Center, 4-9-13, Yonan, Utsunomiya, Tochigi, 320-0834, Japan
3Division of Medical Oncology, Tochigi Cancer Center, 4-9-13, Yonan, Utsunomiya, Tochigi, 320-0834, Japan
4Division of Functional Genomics, Jichi Medical School, 3311-1, Minamikawachi, Tochigi, 329-0431, Japan
5Division of Stem Cell Regulation, Jichi Medical School, 3311-1, Minamikawachi, Tochigi, 329-0431, Japan

The combination of pemetrexed and cisplatin shows good clinical activity against mesothelioma and lung cancer. In order to study the potential cellular basis for this, and provide leads as to how to optimize the combination, we studied the schedule-dependent cytotoxic effects of pemetrexed and cisplatin against four human cancer cell lines in vitro. Tumor cells were incubated with pemetrexed and cisplatin for 24 h at various schedules. The combination effects after 5 days were analyzed by the isobologram method. Both simultaneous exposure to pemetrexed and cisplatin for 24 h and sequential exposure to cisplatin for 24 h followed by pemetrexed for 24 h produced antagonistic effects in human lung cancer A549, breast cancer MCF7, and ovarian cancer PA1 cells and additive effects in colon cancer WiDr cells. Pemetrexed for 24 h followed by cisplatin for 24 h produced synergistic effects in MCF7 cells, additive/synergistic effects in A549 and PA1 cells, and additive effects in WiDr cells. Cell cycle analysis of MCF7 and PA1 cells supported these findings. Our results suggest that the simultaneous clinical administration of pemetrexed and cisplatin may be suboptimal. The optimal schedule of pemetrexed in combination with cisplatin at the cellular level is the sequential administration of pemetrexed followed by cisplatin and this schedule is worthy of clinical investigations.

Key words: Pemetrexed; Cisplatin; Isobologram; Synergism; Antagonism

Address correspondence to Yasuhiko Kano, Division of Hematology, Tochigi Cancer Center, Yonan 4-9-13, Utsunomiya, Tochigi, 320-0834, Japan. Tel: 011-81-28-658-5151; Fax: 011-81-28-658-5488; E-mail: ykano@tcc.pref.tochigi.jp




Oncology Research, Vol. 16, pp. 97-106
0965-0407/06 $90.00 + .00
E-ISSN 1555-3906
Copyright © 2006 Cognizant Comm. Corp.
Printed in the USA. All rights reserved.

Synthesis and Antimelanoma Activity of Reversed Amide Analogues of N-Acetyl-4-S-cysteaminylphenol

Kathryn Nicoll,1 Jane Robertson,1 Neil Lant,1 Lloyd R. Kelland,2* Paul M. Rogers,2* and David J. Robins1

1WestCHEM, Department of Chemistry, University of Glasgow, Glasgow G12 8QQ, UK
2Cancer Research UK Centre for Cancer Therapeutics, Institute of Cancer Research, Haddow Laboratories, 15 Cotswold Road, Belmont, Sutton, Surrey SM2 5NG, UK

The melanin biosynthetic pathway from tyrosine is a potential target for combating malignant melanoma. N-Acetyl-4-S-cysteaminylphenol <b>1 is a previously synthesized analogue of tyrosine that probably acts by this pathway. It interferes with cell growth and proliferation via selective oxidation in melanocytes to an o-quinone that can alkylate cellular nucleophiles. We previously synthesized a range of analogues of the original lead compound 1 most of which displayed greater cytotoxicity than 1. Eighteen new analogues with the amide group reversed have now been synthesized and tested for antimelanoma activity. Most of these reverse amides showed greater cytotoxicity than N-Acetyl-4-S-cysteaminylphenol towards five representative melanoma cell lines. The highest cytotoxicity was observed for the piperidine and hexamethyleneimine derivatives 7, 8, 12, 13, and 17 and the catechol 18. The most active compound, 7, had cytotoxicity comparable to cisplatin against the five melanoma cell lines. The moderate activity of 7 and 18 against SK-Mel-24 (non-tyrosinase containing) and an ovarian cell line suggests that interference with the melanin pathway may not be the only mode of action of these compounds. Assays of some of the compounds as substrates for tyrosinase showed that the catechol 18 was the best substrate and that the piperidine derivative 7 was the best substrate of the phenolic compounds synthesized.

Key words: Antimelanoma; Cysteaminylphenol; Tyrosinase; Amide

Address correspondence to Professor David J. Robins, Department of Chemistry, University of Glasgow, Glasgow, G12 8QQ, UK. Tel: +44-(0)141-330-4378; Fax: +44-(0)141-330-4888; E-mail: D.Robins@chem.gla.ac.uk

*Current address: Antisoma plc, St Georges Hospital Medical School, Cranmer Terrace, London SW17 0QS, UK.