Munenori Takaoka

Publications of Munenori Takaoka

• Strong anti-tumor effect of NVP-AUY922, a novel Hsp90 inhibitor, on non-small cell lung cancer.

  Authors: Tsuyoshi Ueno, Kazunori Tsukuda, Shinichi Toyooka, Midori Ando, Munenori Takaoka, Junichi Soh, Hiroaki Asano, Yuho Maki, Takayuki Muraoka, Norimitsu Tanaka, Kazuhiko Shien, Masashi Furukawa, Tomoki Yamatsuji, Katsuyuki Kiura, Yoshio Naomoto, Shinichiro Miyoshi

  Lung cancer (Amsterdam, Netherlands). 10/2011;

  The anti-tumor activity of a newly developed Hsp90 inhibitor, NVP-AUY922 (AUY922), against non-small cell lung cancer (NSCLC) was examined. Twenty-one NSCLC cell lines were used, the somaticThe anti-tumor activity of a newly developed Hsp90 inhibitor, NVP-AUY922 (AUY922), against non-small cell lung cancer (NSCLC) was examined. Twenty-one NSCLC cell lines were used, the somatic alterations of which were characterized. Cell proliferation was analyzed using a modified MTS assay. Expression of the client proteins was assessed using Western blotting. The cell cycle was analyzed using flow cytometry. The IC(50) value of AUY922 for the NSCLC cell lines ranged from 5.2 to 860nM (median, 20.4nM). Based on previous data, cells with an IC(50) of less than 50nM were classified as sensitive cells and 19 of the 21 NSCLC cell lines were judged to be sensitive. The IC(50) of five malignant pleural mesothelioma (MPM) cell lines revealed that the MPM cells had a significantly higher IC(50) value (median, 89.2nM; range, 22.2-24,100nM) than the NSCLC cells (p=0.015). There was significant depletion of both the total and phosphorylated client proteins - EGFR, MET, HER2 and AKT - at low drug concentrations (50-100nM) in drug-sensitive cell lines. Cell-cycle analysis was performed for two sensitive cell lines, H1975 and H838. Following AUY922 treatment, an increase in the sub-G(0)-G(1) cell population, as well as appearance of cleaved PARP expression, indicated the induction of apoptosis. In conclusion, AUY922 was effective against most NSCLC cell lines, independent of the type of known molecular alteration, and appears to be a promising new drug for the treatment of NSCLC.

• F-18 FDG PET/CT contributes to more accurate detection of lymph nodal metastasis from actively proliferating esophageal squamous cell carcinoma.

  Authors: Shunsuke Tanabe, Yoshio Naomoto, Yasuhiro Shirakawa, Yasuhiro Fujiwara, Kazufumi Sakurama, Kazuhiro Noma, Munenori Takaoka, Tomoki Yamatsuji, Takao Hiraki, Yoshihiro Okumura, Masahiko Mitani, Mitsumasa Kaji, Susumu Kanazawa, Toshiyoshi Fujiwara

  Clinical nuclear medicine. 10/2011; 36(10):854-9.

  Evaluating the status of disease progression is critical for planning a therapeutic strategy for esophageal cancer. In this regard, F-18 fluorodeoxyglucose-labeled positron emission tomography (PET)Evaluating the status of disease progression is critical for planning a therapeutic strategy for esophageal cancer. In this regard, F-18 fluorodeoxyglucose-labeled positron emission tomography (PET) is one of the most useful diagnostic modalities. However, there is room to improve its diagnostic performance, such as distinguishing lymph nodal metastases from false positives. In this study, we examined the diagnostic accuracy of fluorodeoxyglucose PET accompanied by computed tomography imaging (PET/CT) to detect regional lymph nodal metastasis from esophageal squamous cell carcinoma (ESCC). A total of 102 patients diagnosed as ESCC were subjected to this study. These patients had a preoperative PET/CT examination to evaluate the existence of metastasis. The values of maximum standardized uptake value (SUVmax) in primary tumors and in metastasized lymph nodes were measured to analyze their relationship with various clinicopathologic characteristics including the status of tumor cell proliferation, which was assessed by immunohistochemistry for Ki-67. The SUVmax of the primary tumor was positively correlated with tumor size and vessel invasion, and was positively related with the SUVmax of lymph nodal metastasis, especially in cases of poorly differentiated ESCC. The SUVmax of metastasized lymph nodes was higher in larger-sized metastasized lymph nodes, whereas the Ki-labeling index of lymph nodal metastasis was positively related with the SUVmax per unit area (SUVmax/mm). The diagnostic accuracy of PET/CT (87.3%) was higher than that of conventional CT scans (78.4%). The improved diagnostic accuracy of PET/CT can be explained by its ability to detect actively progressive metastasis at an early phase regardless of size.

• Inhibition of mTOR by temsirolimus contributes to prolonged survival of mice with pleural dissemination of non-small-cell lung cancer cells.

  Authors: Toshiaki Ohara, Munenori Takaoka, Shinichi Toyooka, Yasuko Tomono, Toshio Nishikawa, Yasuhiro Shirakawa, Tomoki Yamatsuji, Noriaki Tanaka, Toshiyoshi Fujiwara, Yoshio Naomoto

  Cancer science. 07/2011; 102(7):1344-9.

  Temsirolimus (CCI-779), a recently synthesized analogue of rapamycin, specifically inhibits mTOR and has been approved for clinical use in renal cell carcinoma. Recent reports have indicated theTemsirolimus (CCI-779), a recently synthesized analogue of rapamycin, specifically inhibits mTOR and has been approved for clinical use in renal cell carcinoma. Recent reports have indicated the growth inhibitory effect of temsirolimus in some cancers including non-small-cell lung carcinoma (NSCLC). In this study, we aimed to explore the potential therapeutic use of temsirolimus as a treatment for NSCLC. Using cultured NSCLC cells (A549, H1299, and H358), we determined the effect of temsirolimus on cell proliferation and its antitumor effects on subcutaneous tumors, as well as its contribution to the survival of mice having pleural dissemination of cancer cells, mimicking advanced NSCLC. Temsirolimus suppressed proliferation of NSCLC cells in a dose-dependent manner, with an IC(50) of <1 nM. Western blot analysis revealed that temsirolimus treatment specifically inhibited the phosphorylation of mTOR and its downstream effectors in 1 h, accompanied by an increased cell population in the G(0) /G(1) phase, but according to flow cytometry, the cell population did not increase in the sub-G(0) phase. When NSCLC subcutaneous tumor-bearing mice were treated with temsirolimus, tumor volume was significantly reduced (tumor volume on day 35: vehicle vs temsirolimus = 1239 vs 698 cm(3) ; P < 0.05). Furthermore, prolonged survival was observed in pleural disseminated tumor-bearing mice with temsirolimus treatment (median survival: vehicle vs temsirolimus = 53.5 vs 72.5 days; P < 0.05). These results suggest that temsirolimus could be useful for NSCLC treatment, due to its antiproliferative effect, and could be a potential treatment for advanced NSCLC, giving prolonged survival.

• Antitumor effect of novel HSP90 inhibitor NVP-AUY922 against oral squamous cell carcinoma.

  Authors: Tatsuo Okui, Tsuyoshi Shimo, Nur Mohammad Monsur Hassan, Takuya Fukazawa, Naito Kurio, Munenori Takaoka, Yoshio Naomoto, Akira Sasaki

  Anticancer research. 04/2011; 31(4):1197-204.

  Heat-shock protein 90 (HSP90) is a major cellular chaperone protein. HSP90 supports the correct conformation, stabilization, activation, and localization of 'client' oncoproteins, many of which areHeat-shock protein 90 (HSP90) is a major cellular chaperone protein. HSP90 supports the correct conformation, stabilization, activation, and localization of 'client' oncoproteins, many of which are involved in tumor progression. Therefore, the use of HSP90 inhibitors has become a new strategy in antitumor therapy. However, the effects of an HSP90 inhibitor on oral squamous cell carcinoma are still unclear. NVP-AUY922 (Novartis) is a novel 4,5-diaryloxazole adenosine triphosphate-binding site HSP90 inhibitor. In this study, we investigated the antitumor effect of novel HSP90 inhibitor NVP-AUY922 against oral squamous cell carcinoma. NVP-AUY922 inhibited the proliferation of oral squamous cell carcinoma cells in vitro. NVP-AUY922 caused degradation of client protein inducing ErbB2, p-Akt, p-S6, hypoxia-inducible factor 1-α (HIF1-α) and vascular endothelial growth factor (VEGF) and up-regulation of HSP70 in HSC-2 oral squamous cell carcinoma. NVP-AUY922 increased the expression of cleaved caspase-3 and induced apoptosis in HSC-2 cells. Treatment of NVP-AUY922 induced a robust antitumor response and suppressed p-Akt and VEGF expression in an HSC-2 xenograft model. In summary, NVP-AUY922 exhibits in vitro and in vivo efficiency against oral squamous cell carcinoma, representing a promising therapeutic approach for oral squamous cell carcinoma.

• Anti-tumor effect in human breast cancer by TAE226, a dual inhibitor for FAK and IGF-IR in vitro and in vivo.

  Authors: Naito Kurio, Tsuyoshi Shimo, Takuya Fukazawa, Munenori Takaoka, Tatsuo Okui, Nur Mohammad Monsur Hassan, Tatsuki Honami, Shinji Hatakeyama, Masahiko Ikeda, Yoshio Naomoto, Akira Sasaki

  Experimental cell research. 02/2011; 317(8):1134-46.

  Focal adhesion kinase (FAK) is a 125-kDa non-receptor type tyrosine kinase that localizes to focal adhesions. FAK overexpression is frequently found in invasive and metastatic cancers of the breast,Focal adhesion kinase (FAK) is a 125-kDa non-receptor type tyrosine kinase that localizes to focal adhesions. FAK overexpression is frequently found in invasive and metastatic cancers of the breast, colon, thyroid, and prostate, but its role in osteolytic metastasis is not well understood. In this study, we have analyzed anti-tumor effects of the novel FAK Tyr(397) inhibitor TAE226 against bone metastasis in breast cancer by using TAE226. Oral administration of TAE226 in mice significantly decreased bone metastasis and osteoclasts involved which were induced by MDA-MB-231 breast cancer cells and increased the survival rate of the mouse models of bone metastasis. TAE226 also suppressed the growth of subcutaneous tumors in vivo and the proliferation and migration of MDA-MB-231 cells in vitro. Significantly, TAE226 inhibited the osteoclast formation in murine pre-osteoclastic RAW264.7 cells, and actin ring and pit formation in mature osteoclasts. Moreover, TAE226 inhibited the receptor activator for nuclear factor κ B Ligand (RANKL) gene expression induced by parathyroid hormone-related protein (PTHrP) in bone stromal ST2 cells and blood free calcium concentration induced by PTHrP administration in vivo. These findings suggest that FAK was critically involved in osteolytic metastasis and activated in tumors, pre-osteoclasts, mature osteoclasts, and bone stromal cells and TAE226 can be effectively used for the treatment of cancer induced bone metastasis and other bone diseases.

• Glutamine depletion induces murine neonatal melena with increased apoptosis of the intestinal epithelium.

  Authors: Takayuki Motoki, Yoshio Naomoto, Junji Hoshiba, Yasuhiro Shirakawa, Tomoki Yamatsuji, Junji Matsuoka, Munenori Takaoka, Yasuko Tomono, Yasuhiro Fujiwara, Hiroshi Tsuchita, Mehmet Gunduz, Hitoshi Nagatsuka, Noriaki Tanaka, Toshiyoshi Fujiwara

  World journal of gastroenterology : WJG. 02/2011; 17(6):717-26.

  To investigate the possible biological outcome and effect of glutamine depletion in neonatal mice and rodent intestinal epithelial cells. We developed three kinds of artificial milk with differentTo investigate the possible biological outcome and effect of glutamine depletion in neonatal mice and rodent intestinal epithelial cells. We developed three kinds of artificial milk with different amounts of glutamine; Complete amino acid milk (CAM), which is based on maternal mouse milk, glutamine-depleted milk (GDM), and glutamine-rich milk (GRM). GRM contains three-fold more glutamine than CAM. Eighty-seven newborn mice were divided into three groups and were fed with either of CAM, GDM, or GRM via a recently improved nipple-bottle system for seven days. After the feeding period, the mice were subjected to macroscopic and microscopic observations by immunohistochemistry for 5-bromo-2'-deoxyuridine (BrdU) and Ki-67 as markers of cell proliferation, and for cleaved-caspase-3 as a marker of apoptosis. Moreover, IEC6 rat intestinal epithelial cells were cultured in different concentrations of glutamine and were subject to a 4-[3-(4-iodophenyl)-2-(4-nitrophenyl)-2H-5-tetrazolio]-1,3-benzene disulfonate cell proliferation assay, flow cytometry, and western blotting to examine the biological effect of glutamine on cell growth and apoptosis. During the feeding period, we found colonic hemorrhage in six of 28 GDM-fed mice (21.4%), but not in the GRM-fed mice, with no differences in body weight gain between each group. Microscopic examination showed destruction of microvilli and the disappearance of glycocalyx of the intestinal wall in the colon epithelial tissues taken from GDM-fed mice. Intake of GDM reduced BrdU incorporation (the average percentage of BrdU-positive staining; GRM: 13.8%, CAM: 10.7%, GDM: 1.14%, GRM vs GDM: P < 0.001, CAM vs GDM: P < 0.001) and Ki-67 labeling index (the average percentage of Ki-67-positive staining; GRM: 24.5%, CAM: 22.4% GDM: 19.4%, GRM vs GDM: P = 0.001, CAM vs GDM: P = 0.049), suggesting that glutamine depletion inhibited cell proliferation of intestinal epithelial cells. Glutamine deprivation further caused the deformation of the nuclear membrane and the plasma membrane, accompanied by chromatin degeneration and an absence of fat droplets from the colonic epithelia, indicating that the cells underwent apoptosis. Moreover, immunohistochemical analysis revealed the appearance of cleaved caspase-3 in colonic epithelial cells of GDM-fed mice. Finally, when IEC6 rat intestinal epithelial cells were cultured without glutamine, cell proliferation was significantly suppressed after 24 h (relative cell growth; 4 mmol/L: 100.0% ± 36.1%, 0 mmol/L: 25.3% ± 25.0%, P < 0.05), with severe cellular damage. The cells underwent apoptosis, accompanied by increased cell population in sub-G0 phase (4 mmol/L: 1.68%, 0.4 mmol/L: 1.35%, 0 mmol/L: 5.21%), where dying cells are supposed to accumulate. Glutamine is an important alimentary component for the maintenance of intestinal mucosa. Glutamine deprivation can cause instability of the intestinal epithelial alignment by increased apoptosis.

• Antitumor effect of temsirolimus against oral squamous cell carcinoma associated with bone destruction.

  Authors: Tatsuo Okui, Tsuyoshi Shimo, Takuya Fukazawa, Naito Kurio, Nur Mohammad Monsur Hassan, Tatsuki Honami, Munenori Takaoka, Yoshio Naomoto, Akira Sasaki

  Molecular cancer therapeutics. 11/2010; 9(11):2960-9.

  The mammalian target of rapamycin (mTOR) is engaged in the molecular pathogenesis of oral squamous cell carcinoma, which frequently invades the maxilla or the mandible. However, the effects of a mTORThe mammalian target of rapamycin (mTOR) is engaged in the molecular pathogenesis of oral squamous cell carcinoma, which frequently invades the maxilla or the mandible. However, the effects of a mTOR inhibitor on bone destruction associated with oral squamous cell carcinoma are still unclear. In this study, we investigated the antitumor effect of temsirolimus-mediated mTOR inhibition against advanced oral squamous cell carcinoma. Temsirolimus inhibited the proliferation and migration of HSC-2 oral squamous cell carcinoma cells in vitro and suppressed the growth of oral squamous cell carcinoma xenografts in vivo. Significantly, we clearly show that temsirolimus inhibited osteoclast formation both in vitro and in vivo. Reverse transcriptase-PCR analysis showed that temsirolimus decreased the mRNA expression of receptor activator for nuclear factor-κB ligand, known as an osteoclast differentiation factor in bone stromal ST2 cells. Moreover, temsirolimus normalized blood-free calcium concentration in mouse models for humoral hypercalcemia. These findings suggest that mTOR signaling is a potential target of oral squamous cell carcinoma associated with bone destruction, and hence we describe the efficacy of temsirolimus for the treatment of advanced oral squamous carcinoma.

• Preferential up-regulation of heparanase and cyclooxygenase-2 in carcinogenesis of Barrett's oesophagus and intestinal-type gastric carcinoma.

  Authors: Ryotaro Sonoda, Yoshio Naomoto, Yasuhiro Shirakawa, Yasuhiro Fujiwara, Tomoki Yamatsuji, Kazuhiro Noma, Shunsuke Tanabe, Munenori Takaoka, Mehmet Gunduz, Hidetsugu Tsujigiwa, Hitoshi Nagatsuka, Nobuya Ohara, Tadashi Yoshino, Kaiyo Takubo, Michael Vieth, Noriaki Tanaka

  Histopathology. 07/2010; 57(1):90-100.

  Metaplastic changes secondary to chronic inflammation at the gastro-oesophageal junction and at the pyloric antrum are recognized as the premalignant conditions of Barrett's oesophagealMetaplastic changes secondary to chronic inflammation at the gastro-oesophageal junction and at the pyloric antrum are recognized as the premalignant conditions of Barrett's oesophageal adenocarcinoma and intestinal-type gastric carcinoma (GC), respectively. Heparanase (HPSE) and cyclooxygenase (COX)-2 have been proved to play critical roles in inflammation as well as in cancer. The aim was to examine the meaning of their expression in inflammation-related carcinogenesis. First, expression of HPSE and COX-2 in 78 clinical tissues of Barrett's oesophagus was examined by immunohistochemistry and in situ hybridization. Their expression was increased during the metaplasia-dysplasia sequence with increased neovascularization. Successively, their expression in Barrett's dysplasia was compared with that of GC (22 cases of diffuse-type and 10 of intestinal-type). Interestingly, the expression pattern in Barrett's dysplasia was similar to that in intestinal-type GC, which mainly arises from chronic inflammation. Furthermore, cultured cell lines isolated from differentiated GC tissues, which are often found to be of intestinal-type, revealed up-regulated mRNA expression of HPSE and COX-2. HPSE and COX-2 are preferentially up-regulated in Barrett's oesophagus and intestinal-type GC. These molecules may play an important role during the development of inflammation-related adenocarcinoma of the upper gastrointestinal tract.

• HSP90 and its inhibitors.

  Authors: Huifang Hao, Yoshio Naomoto, Xiaohong Bao, Nobuyuki Watanabe, Kazufumi Sakurama, Kazuhiro Noma, Takayuki Motoki, Yasuko Tomono, Takuya Fukazawa, Yasuhiro Shirakawa, Tomoki Yamatsuji, Junji Matsuoka, Munenori Takaoka

  Oncology reports. 06/2010; 23(6):1483-92.

  The HSP90 molecular chaperone family is highly conserved and expressed in various organisms ranging from prokaryotes to eukaryotes. HSP90 proteins play essential housekeeping functions, such asThe HSP90 molecular chaperone family is highly conserved and expressed in various organisms ranging from prokaryotes to eukaryotes. HSP90 proteins play essential housekeeping functions, such as controlling the activity, turnover and trafficking of various proteins, promoting cell survival through maintaining the structural and functional integrity of some client proteins which control cell survival, proliferation and apoptosis, and play an important role in the progression of malignant disease. HSP90 proteins are ATP-dependent chaperones and the binding and hydrolysis of ATP are coupled to conformation changes of HSP90, which facilitate client protein folding and maturation. Many natural and synthetic molecular compounds have been proposed as promising cancer therapy via disrupting the formation of complex ATP-HSP90-client proteins.

• Autophagy: Can it become a potential therapeutic target?

  Authors: Xiao Hong Bao, Yoshio Naomoto, Hui Fang Hao, Nobuyuki Watanabe, Kazufumi Sakurama, Kazuhiro Noma, Takayuki Motoki, Yasuko Tomono, Takuya Fukazawa, Yasuhiro Shirakawa, Tomoki Yamatsuji, Junji Matsuoka, Munenori Takaoka

  International journal of molecular medicine. 04/2010; 25(4):493-503.

  Autophagy is a cellular lysosomal degradation pathway involved in proteins and organelles recycling for promoting cell survival, development and homeostasis. It is a multistep process and geneticAutophagy is a cellular lysosomal degradation pathway involved in proteins and organelles recycling for promoting cell survival, development and homeostasis. It is a multistep process and genetic studies have identified many proteins that participate in autophagosome formation and fusion with lysosomes, and various signaling factors that associate with the regulation of autophagy. In general, autophagy acts as a cell protector and its dysfunction is correlated with diverse pathologies, such as neurodegeneration, liver, heart and muscle diseases, cancer, inflammation and ageing. However, its role in cell death increases the complexity of the autophagic degradation system. A broad understanding of autophagy, ranging from detailed processes, including induction, formation and degradation, to function in physiology and pathology, revealed by accumulating studies, may be helpful for formulating therapeutic strategies for autophagy-associated human diseases.

• RAD001 offers a therapeutic intervention through inhibition of mTOR as a potential strategy for esophageal cancer.

  Authors: Zhi Gang Wang, Takuya Fukazawa, Toshio Nishikawa, Nobuyuki Watanabe, Kazufumi Sakurama, Takayuki Motoki, Shinji Hatakeyama, Osamu Omori, Toshiaki Ohara, Shunsuke Tanabe, Yasuhiro Fujiwara, Munenori Takaoka, Yasuhiro Shirakawa, Tomoki Yamatsuji, Noriaki Tanaka, Yoshio Naomoto

  Oncology reports. 04/2010; 23(4):1167-72.

  Esophageal cancer is one of the most frequently occurring cancers in the world. Targeting therapy strategy of cancer with specific inhibitors is developing and has showed promising antitumorEsophageal cancer is one of the most frequently occurring cancers in the world. Targeting therapy strategy of cancer with specific inhibitors is developing and has showed promising antitumor efficacy. It is known that mTOR is an important controller of cell growth. RAD001 (everolimus) is a specific inhibitor of mTOR that can block the mTOR signaling pathway. The purposes of this study was to explore the inhibitory effects of RAD001 on mTOR signaling and the mechanism of cell growth suppression by RAD001. We examined both the expression of mTOR, p70S6K and S6 in SEG-1 esophageal cancer cells and KOB-13 normal esophageal epithelial cells and the efficacy of RAD001 against SEG-1 esophageal cancer cells. mTOR, p70S6K and S6 were overexpressed in SEG-1 esophageal cancer cells compared with KOB-13 normal esophageal epithelial cells. SEG-1 esophageal cancer cells were sensitive to RAD001. The survival rate of the cells treated with RAD001 over 0.33 microM was significantly different compared with that of control (P<0.01). RAD001 inhibited the phosphorylation of mTOR (Ser2448) and S6 (Ser240/244) in different grades and the expressions of mTOR, p70S6K and S6. As a result, RAD001 induced a dose-dependent decrease in cell proliferation, G1/S arrest and damage of cell shape. Taken together, these data showed that RAD001 can inhibit mTOR signaling and proliferation in SEG-1 esophageal cancer cells in vitro. It offers a therapeutic intervention through inhibition of mTOR as a potential strategy for esophageal cancer.

• Hypoxia activates the cyclooxygenase-2-prostaglandin E synthase axis.

  Authors: James J Lee, Mitsuteru Natsuizaka, Shinya Ohashi, Gabrielle S Wong, Munenori Takaoka, Carmen Z Michaylira, Daniela Budo, John W Tobias, Michiyuki Kanai, Yasuhiro Shirakawa, Yoshio Naomoto, Andres J P Klein-Szanto, Volker H Haase, Hiroshi Nakagawa

  Carcinogenesis. 03/2010; 31(3):427-34.

  Hypoxia-inducible factors (HIFs), in particular HIF-1alpha, have been implicated in tumor biology. However, HIF target genes in the esophageal tumor microenvironment remain elusive. Gene expressionHypoxia-inducible factors (HIFs), in particular HIF-1alpha, have been implicated in tumor biology. However, HIF target genes in the esophageal tumor microenvironment remain elusive. Gene expression profiling was performed upon hypoxia-exposed non-transformed immortalized human esophageal epithelial cells, EPC2-hTERT, and comparing with a gene signature of esophageal squamous cell carcinoma (ESCC). In addition to known HIF-1alpha target genes such as carbonic anhydrase 9, insulin-like growth factor binding protein-3 (IGFBP3) and cyclooxygenase (COX)-2, prostaglandin E synthase (PTGES) was identified as a novel target gene among the commonly upregulated genes in ESCC as well as the cells exposed to hypoxia. The PTGES induction was augmented upon stabilization of HIF-1alpha by hypoxia or cobalt chloride under normoxic conditions and suppressed by dominant-negative HIF-1alpha. Whereas PTGES messenger RNA (mRNA) was negatively regulated by normoxia, PTGES protein remained stable upon reoxygenation. Prostaglandin E(2) (PGE(2)) biosynthesis was documented in transformed human esophageal cells by ectopic expression of PTGES as well as RNA interference directed against PTGES. Moreover, hypoxia stimulated PGE(2) production in a HIF-1alpha-dependent manner. In ESCC, PTGES was overexpressed frequently at the mRNA and protein levels. Finally, COX-2 and PTGES were colocalized in primary tumors along with HIF-1alpha and IGFBP3. Activation of the COX-2-PTGES axis in primary tumors was further corroborated by concomitant upregulation of interleukin-1beta and downregulation of hydroxylprostaglandin dehydrogenase. Thus, PTGES is a novel HIF-1alpha target gene, involved in prostaglandin E biosynthesis in the esophageal tumor hypoxic microenvironment, and this has implications in diverse tumors types, especially of squamous origin.

• The establishment of a new mouse model with orthotopic esophageal cancer showing the esophageal stricture.

  Authors: Toshiaki Ohara, Munenori Takaoka, Kazufumi Sakurama, Kaori Nagaishi, Haruo Takeda, Yasuhiro Shirakawa, Tomoki Yamatsuji, Takeshi Nagasaka, Junji Matsuoka, Noriaki Tanaka, Yoshio Naomoto

  Cancer letters. 02/2010; 293(2):207-12.

  We established a promising new experimental animal model with an orthotopic xenograft of esophageal cancer that successfully represents poor oral intake, a major clinical feature of esophagealWe established a promising new experimental animal model with an orthotopic xenograft of esophageal cancer that successfully represents poor oral intake, a major clinical feature of esophageal cancer. The advantage of this model is that no surgical technique is required, only the injection of a cell suspension by a needle and syringe via the esophageal lumen from the mouth, which provides a high reproducibility of tumor implantation and a rapid progress of outcome. We propose that this model is useful to study cancer-related outcomes and for developing new therapies for esophageal cancer, and we expect it to make a contribution to clinical practice.

• Progress in researches about focal adhesion kinase in gastrointestinal tract.

  Authors: Hui Fang Hao, Yoshio Naomoto, Xiao Hong Bao, Nobuyuki Watanabe, Kazufumi Sakurama, Kazuhiro Noma, Yasuko Tomono, Takuya Fukazawa, Yasuhiro Shirakawa, Tomoki Yamatsuji, Junji Matsuoka, Munenori Takaoka

  World journal of gastroenterology : WJG. 12/2009; 15(47):5916-23.

  Focal adhesion kinase (FAK) is a 125-kDa non-receptor protein tyrosine. Growth factors or the clustering of integrins facilitate the rapid phosphorylation of FAK at Tyr-397 and this in turn recruitsFocal adhesion kinase (FAK) is a 125-kDa non-receptor protein tyrosine. Growth factors or the clustering of integrins facilitate the rapid phosphorylation of FAK at Tyr-397 and this in turn recruits Src-family protein tyrosine kinases, resulting in the phosphorylation of Tyr-576 and Tyr-577 in the FAK activation loop and full catalytic FAK activation. FAK plays a critical role in the biological processes of normal and cancer cells including the gastrointestinal tract. FAK also plays an important role in the restitution, cell survival and apoptosis and carcinogenesis of the gastrointestinal tract. FAK is over-expressed in cancer cells and its over-expression and elevated activities are associated with motility and invasion of cancer cells. FAK has been proposed as a potential target in cancer therapy. Small molecule inhibitors effectively inhibit the kinase activity of FAK and show a potent inhibitory effect for the proliferation and migration of tumor cells, indicating a high potential for application in cancer therapy.

• [The transition of therapy for recurrent esophageal cancer by PET-CT].

  Authors: Yasuhiro Shirakawa, Shunsuke Tanabe, Yasuhiro Fujiwara, Kazuhiro Noma, Kazufumi Sakurama, Munenori Takaoka, Tomoki Yamatsuji, Minoru Haisa, Yoshio Naomoto

  Gan to kagaku ryoho. Cancer & chemotherapy. 11/2009; 36(12):2465-7.

  In our institute, we introduced PET-CT examination as the preoperative and postoperative screening for esophageal cancer patients in April 2006. During two years before the introduction of PET-CTIn our institute, we introduced PET-CT examination as the preoperative and postoperative screening for esophageal cancer patients in April 2006. During two years before the introduction of PET-CT examination, we performed an intensive local control therapy (operation, RFA, definitive chemoradiotherapy) to 13 cases with single region recurrence (including 5 cases of cervical lymph nodes recurrence, 5 of local recurrence, 3 of distant metastatic recurrence). On the other hand, we performed an intensive local control therapy to 21 cases (including 4 cases of cervical lymph nodes recurrence, 10 of local recurrence, and 7 of distant metastatic recurrence) during two years after the introduction of PET-CT examination. In any pattern, there was a tendency of improvement in the prognosis of recurrent esophageal cancer patients. These results raised the possibility that PET-CT examination was useful for an early detection of the recurrent lesions in postoperative follow-up for esophageal cancer patients. And there might be a chance of curability in patients with single region recurrence by the early detection.

• Focal adhesion kinase as potential target for cancer therapy (Review).

  Authors: Huifang Hao, Yoshio Naomoto, Xiaohong Bao, Nobuyuki Watanabe, Kazufumi Sakurama, Kazuhiro Noma, Takayuki Motoki, Yasuko Tomono, Takuya Fukazawa, Yasuhiro Shirakawa, Tomoki Yamatsuji, Junji Matsuoka, Z G Wang, Munenori Takaoka

  Oncology reports. 11/2009; 22(5):973-9.

  Focal adhesion kinase (FAK) is a 125-kDa non-receptor and non-membrane protein tyrosine. FAK can function with integrins and growth factor receptors to promote cell survival dependent kinase activityFocal adhesion kinase (FAK) is a 125-kDa non-receptor and non-membrane protein tyrosine. FAK can function with integrins and growth factor receptors to promote cell survival dependent kinase activity and nuclear FAK promotes cell proliferation and survival through FERM (FAK, ezrin, radixin, moesin) domain-enhanced p53 degradation independent kinase activity. Many previous studies have indicated that FAK plays a critical role in the biological processes of normal and cancer cells and FAK has been proposed as a potential target in cancer therapy. Small molecule inhibitors (PF-573,228; PF-562,271 and NVP-226) for use as potential cancer therapies have been developed. However, the detailed mechanism of the role for FAK in tumor cell generation and progression remain unclear, so future work is needed to explore these issues. New inhibitors that can be effectively inhibit the function of FAK still need to be explored due to the low specificity, and resistance.

• Involvement of focal adhesion kinase in the progression and prognosis of gastrointestinal stromal tumors.

  Authors: Nobuyuki Kamo, Yoshio Naomoto, Yasuhiro Shirakawa, Tomoki Yamatsuji, Seiichi Hirota, Yasuhiro Fujiwara, Kazuhiro Noma, Kazufumi Sakurama, Munenori Takaoka, Hitoshi Nagatsuka, Mehmet Gunduz, Junji Matsuoka, Noriaki Tanaka

  Human pathology. 09/2009;

  Gastrointestinal stromal tumors often express gene mutations to c-KIT and platelet-derived growth factor receptor-alpha, both of which result in constitutive activations of their signaling pathwaysGastrointestinal stromal tumors often express gene mutations to c-KIT and platelet-derived growth factor receptor-alpha, both of which result in constitutive activations of their signaling pathways that are quite essential for the proliferation and survival of tumor cells in most clinical gastrointestinal stromal tumors. Targeting these molecules provides a dramatic improvement to therapeutic strategy. To identify a new therapeutic target for gastrointestinal stromal tumor treatment, we focused on focal adhesion kinase, which is reported to be an up-regulated gene in clinical gastrointestinal stromal tumors, because so far no one has examined its expression status at the protein level. In this study, Western blot analysis revealed that all 10 of the examined gastrointestinal stromal tumor tissues strongly expressed focal adhesion kinase protein and that phosphorylated focal adhesion kinase was detected in 9 of them. Next, we assessed the expression status of focal adhesion kinase and phosphorylated focal adhesion kinase in 51 cases of gastrointestinal stromal tumor by immunohistochemistry. Positive stainings for focal adhesion kinase and phosphorylated focal adhesion kinase were confirmed in 44 (86.3%) and in 40 cases (78.4%) of the 51 gastrointestinal stromal tumors, respectively. We further found that the focal adhesion kinase-positive staining rate became higher along with the increased status of malignant behavior. Moreover, when the 51 gastrointestinal stromal tumors were divided into 2 groups based upon their focal adhesion kinase expression status, the 5-year overall survival of patients in the focal adhesion kinase-positive group (66.5%) was significantly poorer than that in the focal adhesion kinase-negative group (100%). These results indicate that the up-regulation of focal adhesion kinase protein may also contribute to the tumor progression of gastrointestinal stromal tumors and that focal adhesion kinase is a potential target for gastrointestinal stromal tumor treatment.

• [A Case Report of FOLFOX Treatment for Primary Duodenal Carcinoma with Multiple Liver Metastases.]

  Authors: Yasuhiro Fujiwara, Yoshio Naomoto, Shunsuke Tanabe, Kazufumi Sakurama, Kazuhiro Noma, Toshio Nishikawa, Takayuki Motoki, Munenori Takaoka, Yasuhiro Shirakawa, Tomoki Yamatsuji, Junji Matsuoka, Noriaki Tanaka

  Gan to kagaku ryoho. Cancer & chemotherapy. 05/2009; 36(4):655-7.

  We report a case of a woman in her sixties having primary duodenal carcinoma with multiple liver metastases who was treated with oxaliplatin in combination with infusionalWe report a case of a woman in her sixties having primary duodenal carcinoma with multiple liver metastases who was treated with oxaliplatin in combination with infusional 5-fluorouracil/Leucovorin(FOLFOX regimen). After completing 2 courses of the chemotherapy, computed tomography showed a partial response without any severe adverse events. Now at 8 months, the PR stage has been maintained. So far, no standard therapeutic strategy for metastatic duodenal carcinoma has been developed. However, we suggest a FOLFOX regimen can be highly effective as a safe approach for continuously maintaining the quality of life of patients with this rare type of cancer.

• Immunological aspects of REIC/Dkk-3 in monocyte differentiation and tumor regression.

  Authors: Masami Watanabe, Yuji Kashiwakura, Peng Huang, Kazuhiko Ochiai, Junichiro Futami, Shun-Ai Li, Munenori Takaoka, Yasutomo Nasu, Masakiyo Sakaguchi, Nam-Ho Huh, Hiromi Kumon

  International journal of oncology. 04/2009; 34(3):657-63.

  The REIC/Dkk-3 gene has been reported to be a tumor suppressor and the expression is significantly down-regulated in a broad range of cancer cell types. The protein is secretory, but theThe REIC/Dkk-3 gene has been reported to be a tumor suppressor and the expression is significantly down-regulated in a broad range of cancer cell types. The protein is secretory, but the physiological function remains unclear. This study demonstrated that recombinant REIC/Dkk-3 protein induced the differentiation of human CD14+ monocytes into a novel cell type (REIC/Dkk-3Mo). REIC/Dkk-3Mo resembles immature dendritic cells generated with IL-4 and GM-CSF. Both these cell populations exhibit similar proportions of CD11c+, CD40+, CD86+ and HLA-DR+ cells and endocytic capacity, but REIC/Dkk-3Mo is negative for CD1a antigen. An analysis of the signal transducers and activators of transcription (STAT) pathways revealed that REIC/Dkk-3 induces phosphorylation of STAT 1 and STAT 3. Furthermore, intratumoral administration of REIC/Dkk-3 protein significantly suppressed tumor growth with CD11c+ and CD8+ (dendritic and killer T cell marker, respectively) cell accumulation and enhanced anti-cancer cytolytic activity of splenocytes. These data indicated a cytokine-like role of REIC/Dkk-3 protein in monocyte differentiation that might be exploited therapeutically.

• Resistance to paclitaxel therapy is related with Bcl-2 expression through an estrogen receptor mediated pathway in breast cancer.

  Authors: Yoko Tabuchi, Junji Matsuoka, Mehmet Gunduz, Takako Imada, Ryoko Ono, Mitsuya Ito, Takayuki Motoki, Tomoki Yamatsuji, Yasuhiro Shirakawa, Munenori Takaoka, Minoru Haisa, Noriaki Tanaka, Junichi Kurebayashi, V Craig Jordan, Yoshio Naomoto

  International journal of oncology. 03/2009; 34(2):313-9.

  Taxanes are approved for the treatment of breast cancer that has spread to the lymph nodes, following surgery and doxorubicin containing chemotherapy. Taxanes have improved the survival of breastTaxanes are approved for the treatment of breast cancer that has spread to the lymph nodes, following surgery and doxorubicin containing chemotherapy. Taxanes have improved the survival of breast cancer patients, especially in estrogen receptor (ER) negative population in clinical settings. This time we examined the relationship between chemosensitivity to Taxanes and expresson of ERalpha in breast cancer cell lines. In vitro effects of paclitaxel in 4 ER-positive and 3 ER-negative breast cancer cell lines were investigated by MTT assay. We also investigated members of Bcl-2 family by Western blotting and RT-PCR to clarify their role in paclitaxel resistance both in ER-positive and in ER-negative cells. ER-negative cell lines were more sensitive to paclitaxel than ER-positive cells. ER-negative KPL-4 and ZR-75-30 cells, which were sensitive to paclitaxel, became resistant when they were treated with demethylation agent, 5-aza-2'-deoxycytidine. Analysis of proapoptotic (Bax) and antiapoptotic (Bcl-2) molecules suggested that Bcl-2 is likely to have a role in the resistance of ER-positive cells. Bcl-2 expression was increased in a time-dependent manner after treatment of ER-positive cell lines with estrogen (E2). On the other hand, Bcl-2 was not detected in ER-negative cell lines. However, no significant difference was detected for Bax mRNA levels before and after E2 treatment in ER-positive and negative cell lines. Activation of ER gene expression in ER-negative KPL-4 cells by 5-aza-2'-deoxycytidine resulted in up-regulation of Bcl-2 mRNA. To support our data, we examined paclitaxel sensitivity in ER-negative MDA-MB-231 and ER stable transfectant cells S30 and JM6. This experiment also showed ER-negative cells were sensitive to paclitaxel but ER-positive cells were resistant to it. These results suggest that ER influenced chemosensitivity to paclitaxel through regulation of Bcl-2 family and regulation of the pathway may be crucial to increase the efficacy of taxanes in ER-positive breast cancer.