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Featured researches published by Hiromichi Niikawa.


Cancer Research | 2005

Progesterone receptor in non-small cell lung cancer--a potent prognostic factor and possible target for endocrine therapy.

Hironori Ishibashi; Takashi Suzuki; Satoshi Suzuki; Hiromichi Niikawa; Liangying Lu; Yasuhiro Miki; Takuya Moriya; Shin-ichi Hayashi; Masashi Handa; Takashi Kondo; Hironobu Sasano

A possible involvement of gender-dependent factors has been postulated in development of human non-small-cell lung cancers (NSCLC), but its details remain unclear. In this study, we examined biological significance of progesterone receptor in NSCLCs. Progesterone receptor immunoreactivity was detected in 106 of 228 NSCLCs (46.5%). Progesterone receptor-positive NSCLC was frequently detected in female and adenocarcinoma, and was inversely associated with tumor-node-metastasis stage and histologic differentiation. Progesterone receptor status was also associated with better clinical outcome of the patients, and a multivariate analysis revealed progesterone receptor status as an independent prognostic factor. Progesterone-synthesizing enzymes were detected in NSCLCs, and tissue concentration of progesterone was higher in these cases (n = 42). Immunoblotting analyses showed the presence of progesterone receptor in three NSCLC cell lines (A549, LCSC#2, and 1-87), but not in RERF-LC-OK or PC3. Transcriptional activities of progesterone receptor were increased by progesterone in these three progesterone receptor-positive NSCLC cells by luciferase assays. Cell proliferation was inhibited by progesterone in these progesterone receptor-positive NSCLC cells in a dose-dependent manner, which was inhibited by progesterone receptor blocker. Proliferation of these tumor cells injected into nude mice was also dose-dependently inhibited by progesterone, with a concomitant increase of p21 and p27 and a decrease of cyclin A, cyclin E, and Ki67. Results of our present study suggested that progesterone receptor was a potent prognostic factor in NSCLCs and progesterone inhibited growth of progesterone receptor-positive NSCLC cells. Therefore, progesterone therapy may be clinically effective in suppressing development of progesterone receptor-positive NSCLC patients.


Clinical Cancer Research | 2008

Intratumoral Estrogens and Estrogen Receptors in Human Non–Small Cell Lung Carcinoma

Hiromichi Niikawa; Takashi Suzuki; Yasuhiro Miki; Satoshi Suzuki; Shuji Nagasaki; Jun-ichi Akahira; Seijiro Honma; Dean B. Evans; Shin-ichi Hayashi; Takashi Kondo; Hironobu Sasano

Purpose: The possible involvement of gender-dependent factors has been suggested in human non-small cell lung carcinomas (NSCLC), but their precise roles remain largely unclear. Therefore, we examined intratumoral estradiol concentrations in NSCLC to examine local actions of estrogens in NSCLC. Experimental Design: Fifty-nine frozen specimens of NSCLC were available for liquid chromatography/electrospray tandem mass spectrometry to study intratumoral estradiol concentrations. In addition, A549 NSCLC cells stably expressing estrogen receptor (ER) α (A549 + ERα) or ERβ (A549 + ERβ) were used in vitro studies. Results: Forty-three (73%) of 59 NSCLC showed higher concentration of estradiol in carcinoma tissues than the corresponding nonneoplastic lung tissues from the same patient, and intratumoral estradiol concentrations were significantly (P = 0.0002 and 2.2-fold) higher than the corresponding nonneoplastic lungs. The intratumoral concentration of estradiol was positively correlated with aromatase expression, tumor size, and Ki-67 status in ERα- or ERβ-positive cases. In in vitro studies, estradiol significantly increased cell proliferation of A549 + ERα or A549 + ERβ, which was significantly suppressed by selective ER modulators, tamoxifen or raloxifene. Both A549 + ERα and A549 + ERβ cells expressed aromatase. The cell proliferation level in these cells was significantly increased under treatment with testosterone, and it was inhibited by addition of the aromatase inhibitor letrozole. Conclusions: These results suggest that estradiol is locally produced in NSCLC mainly by aromatase and plays an important role in the growth of ERα- or ERβ-positive NSCLC. Therefore, use of selective ER modulators and/or aromatase inhibitors may be clinically effective in NSCLC that are positive for both ER and aromatase.


Human Pathology | 2010

Highly concordant coexpression of aromatase and estrogen receptor β in non-small cell lung cancer ☆

Keiko Abe; Yasuhiro Miki; Katsuhiko Ono; Miki Mori; Hideaki Kakinuma; Yuki Kou; Nobutaka Kudo; Masashi Koguchi; Hiromichi Niikawa; Satoshi Suzuki; Dean B. Evans; Shunichi Sugawara; Takashi Suzuki; Hironobu Sasano

Estrogen receptor expression has been reported in non-small cell lung cancer. We examined the correlation between aromatase, a key enzyme in the synthesis of estrogen, and estrogen receptor expressions in 105 non-small cell lung cancer cases. All patients were older than 60 years, and all female patients were postmenopausal. Estrogen receptor alpha and progesterone receptor were detected in only 1 and 14 cases, respectively. Estrogen receptor beta and aromatase were positive in 75 and 89 cases respectively. Estrogen receptor beta expression in non-small cell lung cancer showed an inverse correlation with lymph node metastasis (P < .05). Only among females, both estrogen receptor beta and aromatase expressions were correlated with higher Ki-67 labeling index and younger age (P < .05). Among 89 aromatase-positive cases, 70 were positive for estrogen receptor beta, demonstrating a significant concordance (P < .05). Simultaneous immunohistochemical staining for aromatase and estrogen receptor beta showed a high rate of double positive association. Male non-small cell lung cancer cases with double positivity for aromatase and estrogen receptor beta demonstrated lower status in N factor by TNM classification (P < .05). In addition, among 89 aromatase-positive cases, a low-Allred total score of estrogen receptor beta showed a significant relationship with large tumor size and high T factor by TNM classification (P < .05). In conclusion, frequent coexpression of aromatase and estrogen receptor beta in non-small cell lung cancer might suggest some functional correlation between aromatase and estrogen receptor beta, whereas estrogen receptor beta negativity might be correlated with malignant progression of non-small cell lung cancer.


Cancer Research | 2010

Intratumoral localization of aromatase and interaction between stromal and parenchymal cells in the non-small cell lung carcinoma microenvironment.

Yasuhiro Miki; Takashi Suzuki; Keiko Abe; Satoshi Suzuki; Hiromichi Niikawa; Shinya Iida; Shuko Hata; Jun-ichi Akahira; Kazushige Mori; Dean B. Evans; Takashi Kondo; Hisafumi Yamada-Okabe; Hironobu Sasano

Estrogens produced as a result of intratumoral aromatization has been recently shown to play important roles in proliferation of human non-small cell lung carcinomas (NSCLC), but the details have remained largely unknown. Therefore, in this study, we evaluated the possible roles of intratumoral aromatase in NSCLCs as follows: (a) evaluation of intratumoral localization of aromatase mRNA/protein in six lung adenocarcinoma cases using laser capture microdissection combined with quantitative reverse transcriptase-PCR and immunohistochemistry; (b) examination of the possible effects of isolated stromal cells from lung carcinoma tissues on aromatase mRNA transcript expression in lung carcinoma cell lines (A549 and LK87) through a coculture system; and (c) screening of cytokines derived from stromal LK001S and LK002S cells using cytokine antibody arrays and subsequent evaluation of effects of these cytokines on aromatase expression in A549 and LK87. Both aromatase mRNA and protein were mainly detected in intratumoral carcinoma cells but not in stromal cells. Aromatase expression of A549 and LK87 was upregulated in the presence of LK001S or LK002S cells. Several cytokines such as interleukin-6 (IL-6), oncostatin M, and tumor necrosis factor-alpha, all known as inducible factors of aromatase gene, were detected in conditioned media of LK001S and LK002S cells. Treatment of both oncostatin M and IL-6 induced aromatase gene expression in A549 an LK87, respectively. These results all indicated that intratumoral microenvironments, especially carcinoma-stromal cell interactions, play a pivotal role in the regulation of intratumoral estrogen synthesis through aromatase expression in human lung adenocarcinomas.


Respirology | 2009

Preoperative use of inhaled tiotropium in lung cancer patients with untreated COPD.

Seiichi Kobayashi; Satoshi Suzuki; Hiromichi Niikawa; Takafumi Sugawara; Masaru Yanai

Background and objective:  Lung cancer patients with COPD are at high risk during surgery. Tiotropium, a long‐acting bronchodilator, is a preferred maintenance therapy for COPD, but its efficacy in the perioperative period has not been clarified.


Life Sciences | 2012

Co-expression of estrogen receptor beta and aromatase in Japanese lung cancer patients: gender-dependent clinical outcome.

Mohit Kumar Verma; Yasuhiro Miki; Keiko Abe; Shuji Nagasaki; Hiromichi Niikawa; Satoshi Suzuki; Takashi Kondo; Hironobu Sasano

AIM The potential gender differences in lung cancer development have been proposed on the basis of hormonal actions. We aimed to evaluate whether estrogen receptors (ERs) in non-small cell carcinoma (NSCLC) patients may primarily depend upon intratumoral estrogen produced via aromatase pathway. MAIN METHODS We evaluated ER beta (ERβ) and aromatase status in 169 Japanese NSCLC patients through immunohistochemistry analysis (IHC). Significance of IHC was further confirmed in NSCLC cell lines via in vitro assays. KEY FINDINGS IHC analysis of NSCLC patients demonstrated that both ERβ and aromatase were highly co-expressed (p=0.032) in carcinoma cells. Overall survival in males was significantly worse than that in postmenopausal female among double positive NSCLC patients (p=0.010) but not in non-double positive patients. In addition, among double positive cases, overall survival of males was significantly worse than that of postmenopausal females in those with higher ERβ Allred score ≥5, (p=0.034), but not in those with lower ERβ Allred score=3-4. In-vitro analysis demonstrated aromatase activity on testosterone treatment, which resulted in in situ estrogen production (p<0.0001) and increased proliferation of ERβ overexpressing A549 cells (p<0.0001). Aromatase inhibitor i.e. letrozole abrogated this proliferation and also enhanced the androgenic activity (p<0.0001). Testosterone treatment resulted in estrogen responsive elements activation (p<0.0001) in ERβ vector transfected A549 and LK87 cells whereas ER blocker i.e. fulvestrant abrogated this effect, (p<0.0001). SIGNIFICANCE Our results suggest that co-expression of ERβ and aromatase in NSCLCs of Japanese males may result in tumor progression and potential endocrine therapy may confer therapeutic benefits to these patients.


Journal of Translational Medicine | 2013

Intratumoral localization and activity of 17β-hydroxysteroid dehydrogenase type 1 in non-small cell lung cancer: a potent prognostic factor.

Mohit Kumar Verma; Yasuhiro Miki; Keiko Abe; Takashi Suzuki; Hiromichi Niikawa; Satoshi Suzuki; Takashi Kondo; Hironobu Sasano

BackgroundEstrogens were recently demonstrated to be synthesized in non-small cell lung carcinomas (NSCLCs) via aromatase activity and aromatase inhibitor (AI) did suppressed estrogen receptor (ER) positive NSCLC growth. However, other enzymes involved in intratumoral production and metabolism of estrogens, i.e. 17β-hydroxysteroid dehydrogenases (i.e. 17βHSD1 and 17βHSD2) and others have not been studied. Therefore, in this study, we examined the clinical/ biological significance of 17β-hydroxysteroid dehydrogenases in NSCLCs.MethodologyArchival materials obtained from 103 NSCLC patients were immunohistochemically evaluated using anti-17βHSD1 and anti-17βHSD2 antibodies. The findings of immunohistochemistry were then correlated with intratumoral estrone (E1) and estradiol (E2) concentration, clinicopathological factors and overall survival of the patients. We further employed NSCLC cell lines, A549 and LK87 to study the functional significance of 17βHSD1, in vitro.ResultsA higher 17βHSD1 immunoreactivity tended to be positively associated with aromatase (p=0.057) and tumor stage (p=0.055) whereas a higher 17βHSD2 immunoreactivity was positively associated with a squamous cell and adenosquamous cell carcinomas subtypes (p=0.031), tumor stage (p=0.004), T factor of TNM classification (p=0.010), maximum tumor diameter (p=0.002) and tended to be associated with N factor of TMN classification (p=0.065). A higher 17βHSD1 immunoreactivity was also significantly associated with lower intratumoral E1 concentration (p=0.040) and a higher intratumoral E2/E1 concentration ratio (p=0.028). On the other hand a higher 17βHSD2 immunoreactivity was significantly associated with higher intratumoral E1 concentration (p=0.035). Results of multivariate regression analysis demonstrated an increased 17βHSD1 immunoreactivity in tumor cells as an independent negative prognostic factor (HR= 2.83, p=0.007). E1 treatment in 17βHSD1 positive NSCLC cells, A549 and LK87, resulted in E2 production (p<0.0001) and enhanced cell proliferation, which was abrogated effectively by 17βHSD1 siRNA knockdown (p<0.0001). In addition, aromatase inhibitor treatment resulted in 17βHSD1 up regulation in both A549 and LK87 cells.ConclusionResults of our present study suggest that 17βHSD1 may be considered an important prognostic factor in NSCLC patients and targeting 17βHSD1 activity may further improve the clinical response in estrogen responsive NSCLC patients.


Expert Opinion on Therapeutic Targets | 2012

Cytoplasmic estrogen receptor β as a potential marker in human non-small cell lung carcinoma

Mohit Kumar Verma; Yasuhiro Miki; Keiko Abe; Hiromichi Niikawa; Hironobu Sasano

Objectives: Estrogen has been reported to promote an increased susceptibility to lung cancer development. This study focusses on the role of cytoplasmic estrogen receptor β (c-ERβ) in NSCLC. Methods: NSCLC (n = 162) cases were analyzed using immunohistochemistry (IHC) for c-ERβ expression and its association with clinicopathological variables. Significance of c-ERβ expression was further examined using in vitro studies in NSCLC cell lines. Results: Among ERβ and aromatase positive NSCLC females, c-ERβ was significantly associated with greater tumor diameter and tended to be associated with worse overall survival. A549 and LCAM1 cells expressed aromatase, as well as c-ERβ and nuclear ERβ (n-ERβ). U0126 (MAPK/extracellular-signal-regulated kinase (ERK) inhibitor) abrogated MAPK phosphorylation, caused by estradiol via c-ERβ, more effectively than ICI 182780 (ER blocker) in either cell line. However, ICI 182780 completely abrogated the estrogen responsive elements (ERE)-luciferase activity caused by estradiol. Combination therapy with ICI 182780 and U0126 turned out to be far more effective than either treatment alone in either A549 or LCAM1 cells. Conclusion: The results indicated that ERβ may contribute to NSCLC via non-genomic action of estrogen through its cytoplasmic form, in addition to the genomic actions via n-ERβ. These actions of estrogen in NSCLCs may be abrogated by combination therapy with ICI 182780 and U0126.


Thorax | 2014

Dendriform pulmonary ossification: unusual cause of spontaneous pneumothorax

Jiro Abe; Hiroyuki Oura; Hiromichi Niikawa; Hiroshi Yaegashi; Takashi Kondo

A 53-year-old man was admitted to our hospital with a recurrence of spontaneous pneumothorax. He had no history of other diseases including chronic lung diseases. A month prior to this admission, he had a first pneumothorax and was treated with 4 days of intercostal drainage. CT scan showed no bulla, but revealed multiple small polygonal lesions consistent with fibrotic lesions mainly in the right lower lobe (figure 1). We performed right thoracotomy and found that air leakage arose from torn visceral pleura which had been pierced by a drumstick-shaped bony structure (figure 2A). Some other solid flat lesions were palpable in the …


Transplantation proceedings | 2015

Medical consultant system for improving lung transplantation opportunities and outcomes in Japan.

Yasushi Hoshikawa; Yoshinori Okada; J. Ashikari; Yasushi Matsuda; Hiromichi Niikawa; Masafumi Noda; T. Sado; Tatsuaki Watanabe; Hirotsugu Notsuda; F. Chen; M. Inoue; K. Miyoshi; Takeshi Shiraishi; T. Miyazaki; Masayuki Chida; N. Fukushima; Takashi Kondo

Because the shortage of donor organs is especially serious in Japan, since 2002 a unique partnership between transplant consultant physicians and local physicians has been developed to maximize the organ utilization rate. Since 2011, more than 25 lung consultant physicians have been registered to specifically assess donor lungs and provide advice on intensive respiratory care to donors. In this study, we retrospectively reviewed the efficacy of this system for lung transplantation opportunities and outcomes. One hundred eighty-seven brain-dead lung donor candidates were chronologically divided into 3 phases: I (May 1998-November 2006) and II (December 2006-January 2011), before and after medical consultants requested that local physicians administer aggressive bronchial suctioning using bronchoscopy, respectively; and phase III (February 2011-January 2013), after the emergence of lung consultants. The lung utilization rate, Pao2/Fio2 ratio at the first and second brain death examinations and at the tertiary assessment before recovery, and graft survival were analyzed. The lung utilization rate was significantly higher in phases II and III than in phase I. In phases I and II, the Pao2/Fio2 ratio at the tertiary assessment was significantly lower than that at the first or the second brain death examination, whereas it did not worsen with time in phase III. Graft survival was significantly better in phases II and III than in phase I. Graft death due to primary graft dysfunction was significantly more frequent in phase I than in phases II and III. In conclusion, this system is effective in improving lung transplantation opportunities and outcomes.

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