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Honda Y, Yamashita T, Iwamoto N, Goto R, Idera N, Horiguchi K, Miyamoto H, Aruga T, Yamada R, Kuroi K. The therapeutic possibility of intrathecal administration of trastuzumab for the carcinomatous meningitis of HER2-positive metastatic breast cancer: the low penetration of trastuzumab into the cerebrospinal fluid via intravenous administration. Eur J Cancer 2017. [DOI: 10.1016/s0959-8049(17)30143-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022]
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Horiguchi K, Saita C, Onishi M, Iwamoto N, Goto R, Idera N, Honda Y, Miyamoto H, Aruga T, Yamashita T, Horiguchi S, Kuroi K. Roles of CD44 and CD24 in predicting response to neoadjuvant chemotherapy. Eur J Cancer 2017. [DOI: 10.1016/s0959-8049(17)30225-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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Islam MS, Horiguchi K, Iino S, Kaji N, Mikawa S, Hori M, Ozaki H. Epidermal growth factor is a critical regulator of the cytokine IL-33 in intestinal epithelial cells. Br J Pharmacol 2016; 173:2532-42. [PMID: 27300306 DOI: 10.1111/bph.13535] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2015] [Revised: 04/28/2016] [Accepted: 06/08/2016] [Indexed: 01/07/2023] Open
Abstract
BACKGROUND AND PURPOSE IL-33 is a novel cytokine that is believed to be involved in inflammation and carcinogenesis. However, its source, its production and its secretion process remain unclear. Recently, we have reported that IL-33 is up-regulated in dextran sulfate sodium (DSS) colitis in mice. EXPERIMENTAL APPROACH Production of IL-33 from intestinal tissue was studied in a murine cancer model induced by azoxymethane (AOM) and DSS in vivo and in cultures of IEC-6 epithelial cells. Cytokine levels were measured by real time PCR, immunohistochemistry and elisa. KEY RESULTS Mice with AOM/DSS-induced colitis expressed all the characteristic symptoms of colon cancer pathology. Immunohistochemical analysis demonstrated epithelial cell-derived IL-33 in colon tissues from mice with AOM/DSS colitis. Real time PCR and quantitative PCR analysis revealed that AOM/DSS colitis tissues expressed up-regulated IL-1β, IL-33, TGF-β, and EGF mRNA. Gefitinib, an EGFR inhibitor, inhibited IL-33 mRNA expression in AOM/DSS colitis mice. The pathophysiological role of IL-33 in the rat intestinal epithelial cell line (IEC-6 cells) was then investigated. We found that EGF, but not TGF-β1 or PDGF, greatly enhanced mRNA expression of IL-33 and its receptor ST2. In accordance with the gene expression and immunohistochemical analysis of IL-33 levels, elisa-based analysis of cytoplasmic and nuclear extracts showed increased IL-33 protein levels in IEC-6 cells after treatment with EGF. CONCLUSIONS AND IMPLICATIONS Our results suggest that EGF is a key growth factor that increased IL-33 production and ST2 receptor expression during intestinal inflammation and carcinogenesis. The EGF/IL-33/ST2 axis represents a novel therapeutic target in colon cancer.
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Horiguchi K, Nishioka H, Fukuhara N, Yamaguchi-Okada M, Yamada S. A new multilayer reconstruction using nasal septal flap combined with fascia graft dural suturing for high-flow cerebrospinal fluid leak after endoscopic endonasal surgery. Neurosurg Rev 2016; 39:419-27. [PMID: 26886779 DOI: 10.1007/s10143-016-0703-1] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2015] [Revised: 08/12/2015] [Accepted: 10/31/2015] [Indexed: 10/22/2022]
Abstract
This study aimed to evaluate the usefulness and reliability of a new endoscopic multilayer reconstruction using nasal septal flap (NSF) to prevent high-flow cerebrospinal fluid leak after endoscopic endonasal surgery. This study was a retrospective review on 97 patients who underwent multilayer reconstructions using NSF combined with fascia graft dural suturing after endoscopic endonasal surgery between July 2012 and March 2014. Patients were divided into two groups, third ventricle opening group and nonopening group, based on the presence of a direct connection between the third ventricle and the paranasal sinus after tumor removal. Furthermore, we compared this procedure with our previous reconstruction after resection of craniopharyngioma. Finally, we checked the patients who had postoperative prolonged discomfort of the nasal cavity for over a year. Postoperative cerebrospinal fluid (CSF) leak occurred in three patients (3.1 %): one from the third ventricle opening group and the remaining two from the nonopening group. External lumbar drain was performed after surgery in only seven patients (7.2 %). The incidence of postoperative CSF leak was similar in both groups, whereas the rate of craniopharyngioma in the third ventricle opening group was significantly higher. The incidence of postoperative CSF leak after resection of craniopharyngioma was not statistically significant but obviously higher in the previous group (12.2 %) compared with that in the present group (2.3 %). Twelve patients (12.4 %) had postoperative nasal discomfort of the nasal cavity for over a year. Multilayer reconstruction using NSF combined with fascia graft dural suturing is a more reliable method for preventing postoperative high-flow CSF leakage after endoscopic endonasal surgery even if there is a direct connection between the third ventricle and the paranasal sinus. However, we should pay close attention especially to prolonged discomfort of the nasal cavity after harvesting NSF.
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Hirono S, Kawauchi D, Higuchi Y, Setoguchi T, Kihara K, Horiguchi K, Kado K, Sato M, Fukuda K, Nakamura T, Saeki N, Yamakami I. Life-Threatening Intracranial Hypotension after Skull Base Surgery with Lumbar Drainage. J Neurol Surg Rep 2015; 76:e83-6. [PMID: 26251819 PMCID: PMC4520994 DOI: 10.1055/s-0035-1547369] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2014] [Accepted: 12/16/2014] [Indexed: 01/29/2023] Open
Abstract
Although lumbar drainage (LD) is widely used in skull base surgery (SBS), no cases with intracranial hypotension (IH) following LD-assisted SBS have been reported, and skull base surgeons lack awareness of this potentially life-threatening condition. We report two cases of IH after LD-assisted SBS, a spheno-orbital meningioma and an osteosarcoma in the orbit. Despite a minimal amount of cerebrospinal fluid (CSF) drainage and early LD removal, severe postural headache and even a deteriorating consciousness level were observed in the early postoperative course. Neuroimages demonstrated epidural fluid collections, severe midline shift, and tonsillar sag compatible with IH. Epidural blood patch (EBP) immediately and completely reversed the clinical and radiologic findings in both patients. IH should be included in the differential diagnosis of postural headache after LD-assisted SBS that can be managed successfully with EBP. Persistent leakage of CSF at the LD-inserted site leads to IH. Broad dural dissection and wide removal of bony structure may be involved in the midline shift. EBP should be performed soon after conservative management fails. Further reports will determine the risk factors for IH development following LD-assisted SBS.
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Nakagawa A, Ogawa Y, Amano K, Ishii Y, Tahara S, Horiguchi K, Kawamata T, Yano S, Arafune T, Washio T, Kuratsu JI, Saeki N, Okada Y, Teramoto A, Tominaga T. Pulsed Laser-induced Liquid Jet System for Treatment of Sellar and Parasellar Tumors: Safety Evaluation. J Neurol Surg A Cent Eur Neurosurg 2015; 76:473-82. [PMID: 25594817 DOI: 10.1055/s-0034-1396436] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
Abstract
OBJECTIVE The pulsed laser-induced liquid jet (LILJ) system is an emerging surgical instrument intended to assist both maximal removal of the lesion and functional maintenance through preservation of fine vessels and minimal damage to the surrounding tissue. The system ejects the minimum required amount of pulsed water through a handy bayonet-shaped catheter. We have already shown a significant increase in removal rate, in addition to a noteworthy reduction of intraoperative blood loss and procedure time in the treatment of large pituitary and skull base tumors in a single-institution series. The present study evaluated the safety of the system in multiple institutions. METHODS The study included 46 patients, 29 men and 17 women (mean age: 59.1 years) who underwent microsurgical/endoscopic resection of lesions in or in the vicinity of the pituitary fossa through the transsphenoidal approach between October 2011 and June 2012 at six institutions. The histologic diagnoses were pituitary adenoma (31 cases), meningioma (4), craniopharyngioma (3), cavernous angioma (2), and Rathke cyst cleft (1). Lesion volume ranged from 2.0 to 30.4 cm³ (mean: 3.7 cm³). Cavernous sinus invasion was observed in 11 cases and suprasellar extension in 29 cases. RESULTS Preservation of intralesional arteries (diameter: 150 µm) was achieved in all situations in > 80% of cases. Intended surgical steps were achieved except for some restrictions in motion due to the use of an optical quartz fiber. No complications occurred directly related to the use of the device. CONCLUSIONS The LILJ system can be used for safe removal of lesions in or in the vicinity of the pituitary fossa.
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Fukuhara N, Horiguchi K, Nishioka H, Suzuki H, Takeshita A, Takeuchi Y, Inoshita N, Yamada S. Short-term preoperative octreotide treatment for TSH-secreting pituitary adenoma. Endocr J 2015; 62:21-7. [PMID: 25273395 DOI: 10.1507/endocrj.ej14-0118] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
Preoperative control of hyperthyroidism in patients with TSH-secreting pituitary adenomas (TSHoma) may avoid perioperative thyroid storm. Perioperative administration of octreotide may control hyperthyroidism, as well as shrink tumor size. The effects of preoperative octreotide treatment were assessed in a large number of patients with TSHomas. Of 81 patients who underwent surgery for TSHoma at Toranomon Hospital between January 2001 and May 2013, 44 received preoperative short-term octreotide. After excluding one patient because of side effects, 19 received octreotide as a subcutaneous injection, and 24 as a long-acting release (LAR) injection. Median duration between initiation of octreotide treatment and surgery was 33.5 days. Octreotide normalized free T4 in 36 of 43 patients (84%) and shrank tumors in 23 of 38 (61%). Length of octreotide treatment did not differ significantly in patients with and without hormonal normalization (p=0.09) and with and without tumor shrinkage (p=0.84). Serum TSH and free T4 concentrations, duration of treatment, incidence of growth hormone (GH) co-secretion, results of octreotide loading tests, form of administration (subcutaneous injection or LAR), tumor volume, and tumor consistency did not differ significantly in patients with and without hormonal normalization and with and without tumor shrinkage. Short-term preoperative octreotide administration was highly effective for TSHoma shrinkage and normalization of excess hormone concentrations, with tolerable side effects.
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Yamada S, Fukuhara N, Horiguchi K, Yamaguchi-Okada M, Nishioka H, Takeshita A, Takeuchi Y, Ito J, Inoshita N. Clinicopathological characteristics and therapeutic outcomes in thyrotropin-secreting pituitary adenomas: a single-center study of 90 cases. J Neurosurg 2014; 121:1462-73. [PMID: 25237847 DOI: 10.3171/2014.7.jns1471] [Citation(s) in RCA: 81] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT The aim of this study was to analyze clinicopathological characteristics and treatment outcomes in a large single-center clinical series of cases of thyrotropin (TSH)-secreting pituitary adenomas. METHODS The authors retrospectively reviewed clinical, pathological, and treatment characteristics of 90 consecutive cases of TSH-secreting pituitary adenomas treated with transsphenoidal surgery between December 1991 and May 2013. The patient group included 47 females and 43 males (median age 42 years, range 11-74 years). RESULTS Sixteen tumors (18%) were microadenomas and 74 (82%) were macroadenomas. Microadenomas were significantly more frequent in the more recent half of our case series (12 of 45 cases) (p = 0.0274). Cavernous sinus invasion was confirmed in 21 patients (23%). In 67 cases (74%), the tumors were firm elastic or hard in consistency. Acromegaly and hyperprolactinemia were observed, respectively, in 14 (16%) and 11 (12%) of the 90 cases. Euthyroidism was achieved in 40 (83%) of 48 patients and tumor shrinkage was found in 24 (55%) of 44 patients following preoperative somatostatin analog treatment. Conventional transsphenoidal surgery, extended transsphenoidal surgery, and a simultaneous combined supra- and infrasellar approach were performed in 85, 2, and 3 patients, respectively. Total removal with endocrinological remission was achieved in 76 (84%) of 90 patients, including all 16 (100%) patients with microadenomas, 60 (81%) of the 74 with macroadenomas, and 8 (38%) of the 21 with cavernous sinus invasion. None of these 76 patients experienced tumor recurrence during a median follow-up period of 2.8 years. Stratifying by Knosp grade, total removal with endocrinological remission was achieved in 34 of 36 patients with Knosp Grade 0 tumors, all 24 of those with Grade 1 tumors, 12 of the 14 with Grade 2 tumors, 6 of the 8 with Grade 3 tumors, and none of the 8 with Grade 4 tumors. Cavernous sinus invasion and tumor size were significant independent predictors of surgical outcome. Immunoreactivity for growth hormone, prolactin, or both hormones was present in 32, 9, and 24 patients, respectively. The Ki-67 labeling index was less than 3% in 71 (97%) of 73 tumors for which it was obtained and 3% or more in 2. Postsurgery pituitary dysfunction was found in 15 patients (17%) and delayed hyponatremia was seen in 9. CONCLUSIONS TSH-secreting adenomas, particularly those in the microadenoma stage, have increased in frequency over the past 5 years. The high surgical success rate achieved in this series is due to relatively early diagnosis and relatively small tumor size. In addition, the surgical strategies used, such as extracapsular removal of hard or solid adenomas, aggressive resction of tumors with cavernous sinus invasion, or extended transsphenoidal surgery or a simultaneous combined approach for large/giant multilobulated adenomas, also may improve remission rate with a minimal incidence of complications.
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Horiguchi K, Kato H, Nishioka H, Fukuhara N, Takeda H, Yamada S. Delayed postoperative epistaxis from the posterior lateral nasal branch of the sphenopalatine artery after endoscopic endonasal approach: Case report. INTERDISCIPLINARY NEUROSURGERY 2014. [DOI: 10.1016/j.inat.2014.05.004] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022] Open
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Islam MS, Kusakabe M, Horiguchi K, Iino S, Nakamura T, Iwanaga K, Hashimoto H, Matsumoto S, Murata T, Hori M, Ozaki H. PDGF and TGF-β promote tenascin-C expression in subepithelial myofibroblasts and contribute to intestinal mucosal protection in mice. Br J Pharmacol 2014; 171:375-88. [PMID: 24116743 DOI: 10.1111/bph.12452] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2013] [Revised: 09/02/2013] [Accepted: 09/29/2013] [Indexed: 01/25/2023] Open
Abstract
BACKGROUND AND PURPOSE Tenascin-C (TnC) is a multi-domain extracellular matrix glycoprotein that is expressed at a high level during embryogenesis but is almost absent during normal postnatal life. This multi-domain complex molecule is reported to associate with both pro-inflammatory and anti-inflammatory signalling cascades. In this study, we examined how TnC modulated intestinal inflammation. EXPERIMENTAL APPROACH TnC pathophysiology was evaluated in cultures of rat intestinal subepithelial myofibroblasts (ISEMF) and intestinal epithelial cells. Wild-type and TnC(-/-) mice were treated with dextran sodium sulfate (DSS) to induce colitis. KEY RESULTS DSS-induced colitis in mice markedly increased TnC in the damaged mucosal areas and up-regulated mRNA for TnC, pro-inflammatory cytokines and growth factors (PDGF-B and TGF-β1). In addition, 2,4,6-trinitrobenzene sulfonic acid-induced colitis and SAMP1/Yit mice, a model of spontaneous Crohn's disease, also exhibited increased mucosal TnC in colon and ilea respectively. PDGF receptor-α (PDGFRα) positive ISEMF were the primary TnC-producing cells in colon tissues. Accordingly, ISEMF collected from the rat colon constitutively expressed both TnC and PDGFRα. PDGF-BB and TGF-β1 up-regulated both TnC mRNA and protein levels in ISEMF. Knock-down of TnC gene increased susceptibility to DSS-induced colitis, compared with TnC(+/+) littermates. TnC(-/-) mice showed marked abrasion of intestinal mucosal barrier and increased inflammatory scores. Moreover, TnC accelerated both trans-well migration and wound healing in epithelial cells. CONCLUSIONS AND IMPLICATIONS The pharmacological profiles of PDGF-BB and TGF-β in colitis tissues and ISEMF suggest that increased TnC production during inflammation contributed to epithelial cell migration, remodelling and protection of intestinal barriers.
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Nishioka H, Fukuhara N, Horiguchi K, Yamada S. Aggressive transsphenoidal resection of tumors invading the cavernous sinus in patients with acromegaly: predictive factors, strategies, and outcomes. J Neurosurg 2014; 121:505-10. [PMID: 25014437 DOI: 10.3171/2014.3.jns132214] [Citation(s) in RCA: 83] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
OBJECT Cavernous sinus (CS) invasion is the most important preoperative predictor of remission in the surgical treatment of growth hormone-producing pituitary adenomas. The purpose of this study was to evaluate the effectiveness of an aggressive technique for removal of tumors invading the CS in patients with acromegaly. METHODS The authors retrospectively reviewed the cases of 150 consecutive patients with acromegaly who underwent primary transsphenoidal surgery in 2010 and 2011. The authors reviewed preoperative Knosp grade, intraoperative findings, histology of the medial wall of the CS, and surgical outcome according to the current consensus criteria for acromegaly. RESULTS Cavernous sinus invasion was identified in 55 patients (36.7%): definite CS involvement by the tumor was observed under direct vision in 41 patients (74.5%), while invasion was histologically verified in 39 patients (70.9%). Invasion increased in frequency with the higher Knosp grade but was observed in 14.4% (13 of 90) of Grade 0 and 1 tumors. Overall, the remission rate fulfilling stringent criteria was 84.7% (127 of 150). Although CS invasion was significantly associated with an unfavorable outcome (p < 0.0001), remission was achieved in 69.1% (38 of 55) of patients with invasion. No major complications occurred in this series. CONCLUSIONS Cavernous sinus invasion is the most significant, independent predictor of unfavorable outcome. Confirmation of invasion requires direct observation within the CS regardless of the microscope or endoscope used. Particularly in cases in which only the medial wall is involved, histological verification is always necessary to detect the occult invasion. Direct removal of the invading tumor, by sharp excision of the medial wall of the CS, is effective and safe and increases the chance of remission.
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Yamashita T, Aruga T, Miyamoto H, Kitagawa D, Idera N, Goto R, Horiguchi K, Kuroi K. Abstract P2-10-04: The clinicopathological features of androgen receptor expression in primary HER2-positive breast carcinomas. Cancer Res 2013. [DOI: 10.1158/0008-5472.sabcs13-p2-10-04] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: Human epidermal growth factor receptor 2 (HER2)-positive breast carcinomas are aggressive subtypes associated with a variable response to systemic therapies. HER2-positive breast carcinomas are not homogeneous, and it has been reported that androgen receptor (AR) signaling is an important determinant of cell growth and relation with HER3 expression. The aim of this study was to investigate the clinicopathological significance of AR expression in primary HER2-positive breast carcinomas.
Patients and Methods: 102 primary HER2-positive breast tumor samples were obtained from patients operated on at the Cancer and Infectious Disease Center, Tokyo Metropolitan Komagome Hospital from 2001 to 2010. 92 tumors were IHC (HercepTest) score 3, whereas 10 were IHC score 2 and FISH- positive. We evaluated AR using immunohistochemistry. Tumors with equal or more than 10% nuclear-stained cells were determined to be positive for AR and the relationship between AR and clinicopathological parameters was analyzed.
The expression of HER3 was evaluated by immunohistochemistry using the following scoring system: 0 (no staining), 1 (less than 20% of cells stained or weak staining), 2 (more than or equal to 20% of cells stained, or strong staining) and the relation with AR expression was examined.
The differences among variables were calculated by chi-square test.
Results: The median age of all patients was 56 years old (from 31 to 84). AR-positive carcinomas corresponded to 37(36.2%) of 102 HER2-positive breast carcinomas. The median age of AR-positive patients was 54 years old while that of AR-negative patients was 57 years old. There was no significant difference between the two groups.
AR-positive carcinomas were not associated with ER and progesterone receptor (PgR) co-expression and nuclear grade. The stage distribution of AR-positive patients was: stage I(n = 23), stage IIA(n = 11), stage IIB (n = 3), and averaged 18.5mm in tumor size, while AR-negative patients distributed as stage I(n = 16), stage IIA(n = 27), stage IIB (n = 15), stage IIIA(n = 5), stage IIIB(n = 2), and averaged 23.7mm in size. AR-positive carcinomas were associated with larger pathological tumor size and more advanced clinical stages, though lymph node involvement did not differ between the two groups.
The HER3 expression score distribution was: scrore 0 (n = 14), score 1 (n = 54), score 2 (n = 34). The expression of HER3 was not associated with clinicopathological parameters. Furthermore, there was no significant relation between AR expression and HER3 expression.
Median follow-up interval was 63 months. 20 patients (19.6%) suffered recurrence. Four patients suffered recurrence in the AR-positive group while there were 16 patients in the AR-negative group. AR-positive patients had significant better prognosis in recurrence than AR-negative patients.
Conclusion: Among HER2-positive breast carcinomas, AR-positive carcinomas have the tendency to be smaller in tumor size and of early clinical stage compared with those that are AR-negative. The expression of AR might be a better prognostic factor in HER2-positive breast carcinomas.
Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P2-10-04.
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Honda Y, Aruga T, Goto R, Idera N, Horiguchi K, Kitagawa D, Miyamoto H, Yamashita T, Kuroi K. Abstract P6-11-11: Characteristics of long-term survivors after brain metastases in breast cancer patients. Cancer Res 2013. [DOI: 10.1158/0008-5472.sabcs13-p6-11-11] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Background: Brain metastases (BM) occur in 10%-15% patients of breast cancer patients. It is associated with poor prognosis, requiring great effort to manage local and systemic treatment for BM. The purpose of this study was to analyze the clinico-pathological characteristics of long-term survivors with BM in breast cancer patients.
Method: 63 patients with breast cancer BM diagnosed from 2002 to 2010 at the Tokyo Metropolitan Komagome hospital were included. Long–term survival group (Long) was defined as to be consisted of the patients with survival duration more than 36 months after diagnosed with BM and the patients with less than 36 month was into Short-term survival group (Short) in this study. The clinico-pathological characteristics were compared between these two groups. Survival rate and prognostic factors of BM were analyzed by the Kaplan–Meier method and employed by Log–Rank test. Multivariate analysis was performed by the Cox proportional hazard model.
Results: Median age of the 63 patients was 53 years (range, 35–78). Median survival time after BM was 12 months (range, 1–168), with about 90 percent of cause of death related to BM (e.g. failure of PS due to BM). As for ER and HER2 status, the number of ER+/HER2- (Luminal:Lum), ER+or-/HER2+ (HER2-enrich:Her2-E), ER-/HER2- (Basal:Bas) were 18, 27, 18, respectively. Among those 63 patients, 11 survived 36 months or more after BM. However, there was no difference in the rate of ER status between Long (55%) and Short (38%), there were significantly high rate of Her2-E case in Long (73%) as compared with Short (29%). Median survival duration after diagnosed with BM of Lum, Her2-E and Bas were 11, 37, 3 months, respectively. Prognosis of Bas was significantly poor (Bas vs. Her2-E p<0.001), and although Her2-E was not significant as compared with ER (p = 0.188), survival time after BM of Her2-E was the tendency to be long. In univariate analysis, Karnofsky performance status (KPS≥70 or <70), HER2 status, disease free interval (from initial diagnosis to first recurrence, DFI≥2years or <2years) had significant impact on survival time after BM. (p = 0.0458, 0.0398, 0.0385, respectively). Meningitis status was a borderline. (p = 0.052) In multivariate analysis, KPS, HER2 status and DFI were significant prognostic factors. (KPS: RR 2.08, 95% CI 1.08-4.07; HER2: RR 2.911, 95% CI 1.396- 6.484; DFI: RR 1.933, 95% CI 0.83-4.102)
Conclusions: Although, it was believed that the prognosis after BM was poor, Her2-E BM had a comparatively good prognosis. An existing report supports extension of the survival time after BM by HER2–targeted treatment in BM cases with Her2 positive breast cancer. This newest study reviles the median survival after BM as 37 months in Her2-E BM group, but that of Bas group was only 3 months and this is not improved at all compared with historically reported survival duration (2.4-4.9months). Our reports suggested that the innovation of Her2–targeted treatment leads this surprising improvement of life extension in HER2 positive BM patients but innovation of cytotoxic agents could not contribute toward improvement of clinical outcome in triple negative BM patients. So the necessity of examining the medical treatment of breast cancer BM according to subtype from now on is also considered.
Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-11-11.
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Saeki N, Horiguchi K, Murai H, Hasegawa Y, Hanazawa T, Okamoto Y. Endoscopic endonasal pituitary and skull base surgery. Neurol Med Chir (Tokyo) 2013; 50:756-64. [PMID: 20885110 DOI: 10.2176/nmc.50.756] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Here we describe the procedures of endoscopic pituitary and skull base surgery in our institute. We also review the literature to reveal recent advances in this field. Endonasal approach via the sphenoid ostium was carried out for pituitary lesions without the nasal speculum. Postoperative nasal packing was basically not needed in such cases. For meningiomas, craniopharyngiomas, and giant pituitary adenomas, which required intra-dural procedures, nasal procedures such as middle nasal conchotomy and posterior ethmoidectomy, and skull base techniques such as optic canal decompression and removal of the planum sphenoidale were carried out to gain a wider operative field. Navigation and ultrasonic Doppler ultrasonography were essential. Angled endoscopes allowed more successful removal of tumors under direct visualization extending into the cavernous sinus and lower clivus. If cerebrospinal fluid (CSF) leakage occurred during operation, the dural opening was covered with a vascularized mucoseptal flap obtained from the nasal septum. Lumbar drainage system to prevent postoperative CSF rhinorrhea was frequently not required. Angled suction tips, single-shaft coagulation tools, and slim and longer holding forceps, all of which were newly designed for endoscopic surgery, were essential for smoother procedures. Endonasal endoscopic pituitary surgery allows less invasive transsphenoidal surgery since no postoperative nasal packing and less dependence on lumbar drainage are needed. Endoscopic pituitary surgery will be more common and become a standard procedure. Endoscopic skull base surgery has enabled more aggressive removal of extrasellar tumors with the aid of nasal and skull base techniques. Postoperative CSF leakage is now under control due to novel methods which have been proposed to close the dural defect in a water-tight manner. Endoscopic skull base surgery is more highly specialized, so needs special techniques and surgical training. Patient selection is also important, which needs collaboration with ear, nose, and throat specialists. As a safe and successful procedure in skull base surgery, this complex procedure should be carried out only in specialized hospitals, which deal with many patients with skull base lesions.
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Mine S, Saeki N, Horiguchi K, Hanazawa T, Okamoto Y. Craniofacial Resection for Sinonasal Malignant Tumors: Statistical Analysis of Surgical Outcome over 17 Years at a Single Institution. Skull Base 2012; 21:243-8. [PMID: 22470267 DOI: 10.1055/s-0031-1280686] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
We present a retrospective analysis of surgical outcome of sinonasal malignant tumors. Overall survival (OS), disease-specific survival (DSS), local control (LC), and disease-free survival (DFS) were calculated in 32 patients. Prognostic factors for survival and functional outcomes were investigated. The median follow-up period was 70 months. At 5 years, OS, DSS, LC, and DFS rates were 0.722, 0.745, 0.851, and 0.707, respectively. Prognostic factors for poor OS were involvement of the frontal sinus (p = 0.023), T classification (T4, p = 0.025), surgical complications (p = 0.029), chemotherapy (p = 0.035) postsurgical infection (p = 0.043), involvement of the orbit (p = 0.048), histology (squamous cell carcinoma, p = 0.049), and radiotherapy (p = 0.043). Prognostic factors for poor DSS were radiotherapy (p = 0.030), chemotherapy (p = 0.036), positive surgical margin (p = 0.034), and T classification (T4, p = 0.050). LC was adversely influenced by surgical procedure (combined frontotemporal resection, p = 0.035) and positive surgical margin (p = 0.049). DFS was adversely influenced by positive surgical margin (p = 0.001). Prognostic factors for poor functional outcome were postsurgical infection (p = 0.039), postsurgical complications (p = 0.040), tumor location (maxillary sinus, p = 0.042, orbit, p = 0.0002), number of sinuses involved (number of sinuses involved was inversely proportional to functional outcome, p = 0.027), T classification (T4 p = 0.007), pathology (squamous cell carcinoma, p = 0.023), and chemotherapy (p = 0.048). Craniofacial resection was an effective surgical option.
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Saeki N, Murai H, Horiguchi K. Endoscopic Endonasal Pituitary and Skull Base Surgery: Approach Selection, Monitoring, and Complications Based on More Than 700 Cases. Skull Base Surg 2012. [DOI: 10.1055/s-0032-1314057] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/28/2022]
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Tajima Y, Horiguchi K, Nakano S, Hirono S, Higuchi Y, Oide T, Iwadate Y, Saeki N. [Leptomeningeal carcinomatosis following 27 years remission from breast cancer with epidermoid: a case report]. NO SHINKEI GEKA. NEUROLOGICAL SURGERY 2012; 40:343-349. [PMID: 22466234] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
We herein report a patient with leptomeningeal carcinomatosis (LC) in long-term remission from breast cancer, co-existing with a posterior fossa epidermoid and an increase in the serum CA19-9 level which complicated the diagnosis. A 59-year-old woman underwent a left mastectomy due to breast cancer 27 years ago. She was admitted to our hospital suffering from a headache and diplopia. Her serum CA19-9 level on admission was elevated, and diffusion weighted images showed a high-intensity tumor in the prepontine and left cerebello-pontine cistern. A left lateral suboccipital craniotomy with endoscopic assistance was performed for tissue sampling. The pathological diagnosis was an epidermoid and LC from breast cancer. She died of progression of leptomeningeal carcinomatosis 31 days after surgery. LC alone following long-term remission from breast cancer is extremely rare. Meningeal irritation co-existing with an epidermoid mimicking chemical meningitis is even rarer. Pathological confirmation is required for such rare cases.
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Sekine F, Horiguchi K, Kashino Y, Shimizu Y, Yu LJ, Kobayashi M, Wang ZY. Gene sequencing and characterization of the light-harvesting complex 2 from thermophilic purple sulfur bacterium Thermochromatium tepidum. PHOTOSYNTHESIS RESEARCH 2012; 111:9-18. [PMID: 21594712 DOI: 10.1007/s11120-011-9658-9] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/25/2010] [Accepted: 04/18/2011] [Indexed: 05/30/2023]
Abstract
In this study, gene sequences coding for the light-harvesting (LH) 2 polypeptides from a thermophilic purple sulfur bacterium Thermochromatium tepidum are reported and characterization of the LH2 complex is described. Three sets of pucBA genes have been identified, and the gene products have been analyzed by electrophoresis and reversed-phase chromatography. The result shows that all of the genes are expressed but the distribution of the expression is not uniform. The gene products undergo post-translational modification, where two of the β-polypeptides appear to be N-terminally methylated. Absorption spectrum of the purified LH2 complex exhibits Q (y) transitions at 800 and 854 nm in dodecyl β-maltopyranoside solution, and the circular dichroism spectrum shows a "molischianum"-like characteristic. No spectral change was observed for the LH2 when the bacterium was cultured under different conditions of light intensity. In lauryl dimethylamine N-oxide (LDAO) solution, significant changes in the absorption spectrum were observed. The B850 peak decreased and blue-shifted with increasing the LDAO concentration, whereas the B800 intensity increased without change in the peak position. The spectral changes can be partially or almost completely reversed by addition of metal ions, and the divalent cations seem to be more effective. The results indicate that ionic interactions may exist between LH2, detergent molecules and metal ions. Possible mechanisms involved in the detergent- and cation-induced spectral changes are discussed.
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Horiguchi K, Sakamoto K, Koinuma D, Semba K, Inoue A, Inoue S, Fujii H, Yamaguchi A, Miyazawa K, Miyazono K, Saitoh M. TGF-β drives epithelial-mesenchymal transition through δEF1-mediated downregulation of ESRP. Oncogene 2011; 31:3190-201. [PMID: 22037216 PMCID: PMC3391666 DOI: 10.1038/onc.2011.493] [Citation(s) in RCA: 164] [Impact Index Per Article: 12.6] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
Abstract
Epithelial-mesenchymal transition (EMT) is a crucial event in wound healing, tissue repair and cancer progression in adult tissues. We have recently shown that transforming growth factor (TGF)-β-induced EMT involves isoform switching of fibroblast growth factor receptors by alternative splicing. We performed a microarray-based analysis at single exon level to elucidate changes in splicing variants generated during TGF-β-induced EMT, and found that TGF-β induces broad alteration of splicing patterns by downregulating epithelial splicing regulatory proteins (ESRPs). This was achieved by TGF-β-mediated upregulation of δEF1 family proteins, δEF1 and SIP1. δEF1 and SIP1 each remarkably repressed ESRP2 transcription through binding to the ESRP2 promoter in NMuMG cells. Silencing of both δEF1 and SIP1, but not either alone, abolished the TGF-β-induced ESRP repression. The expression profiles of ESRPs were inversely related to those of δEF1 and SIP in human breast cancer cell lines and primary tumor specimens. Further, overexpression of ESRPs in TGF-β-treated cells resulted in restoration of the epithelial splicing profiles as well as attenuation of certain phenotypes of EMT. Therefore, δEF1 family proteins repress the expression of ESRPs to regulate alternative splicing during TGF-β-induced EMT and the progression of breast cancers.
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Horiguchi K, Toi M, Horiguchi S, Sugimoto M, Naito Y, Hayashi Y, Ueno T, Ohno S, Sekine S, Kitagawa D, Aruga T, Suzuki E, Yamashita T, Funata N, Tomita M, Eishi Y, Kuroi K. OP9 Predictive value of CD24 and CD44 for response to neoadjuvant chemotherapy and prognosis in patients with primary breast cancer. EJC Suppl 2011. [DOI: 10.1016/j.ejcsup.2011.02.010] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
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Yamakami I, Higuchi Y, Horiguchi K, Saeki N. Treatment policy for petroclival meningioma based on tumor size: aiming radical removal in small tumors for obtaining cure without morbidity. Neurosurg Rev 2011; 34:327-34; discussion 334-5. [PMID: 21340545 DOI: 10.1007/s10143-011-0308-7] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2010] [Revised: 09/02/2010] [Accepted: 11/10/2010] [Indexed: 11/26/2022]
Abstract
Aggressive tumor removal is not always the best treatment for petroclival meningioma (PCM). However, radical removal actually provides the cure with minimal morbidity. We evaluated the relation of surgical results and tumor size in the PCM removal to clarify the treatment policy for PCM. This study comprised 32 consecutive patients with newly-diagnosed PCM who underwent tumor removal; tumor size was small (< 3 cm) in 12 patients and large (≥3 cm) in 20. Tumor removal was classified into radical (Simpson's grade I/II) and non-radical (Simpson's grade III/IV). Removal of small PCM was 11 radical and one non-radical; no surgical morbidity/mortality occurred and postoperative regular follow-up using magnetic resonance imaging showed no recurrence in the period of 66±45 months. Removal of large PCM was eight radical and 12 non-radical; despite no mortality, the incidence of permanent cranial nerve deficits and major neurological deficits newly developed postoperatively was 35% and 25%, respectively. Radical removal was significantly more frequent in small PCMs than in large PCMs. Permanent cranial nerve deficits newly developed postoperatively and poor outcome (Karnofsky score ≤80) were significantly more frequent in large PCMs than in small PCMs. Radical removal of small PCM is achieved with minimal morbidity and results in the cure. Notwithstanding high morbidity, aggressive removal of large PCM does not achieve a high rate of radical removal. To find and remove PCM radically while it is small is the only way to cure the disease with minimal morbidity.
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Suzuki S, Suzuki H, Horiguchi K, Tsugawa H, Matsuzaki J, Takagi T, Shimojima N, Hibi T. Delayed gastric emptying and disruption of the interstitial cells of Cajal network after gastric ischaemia and reperfusion. Neurogastroenterol Motil 2010; 22:585-93, e126. [PMID: 20040059 DOI: 10.1111/j.1365-2982.2009.01444.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/21/2023]
Abstract
BACKGROUND Gastrointestinal tract is one of the most susceptible organ systems to ischaemia. Not only mucosal injury but also alterations of the intestinal motility and loss of interstitial cells of Cajal (ICC) have been reported in response to ischaemia and reperfusion (I/R). However, there are few reports on the changes in the gastric motility after gastric I/R. The present study was designed to investigate the alterations in gastric emptying, the ICC and enteric nerves that regulate smooth muscle function in response to gastric I/R. METHODS Seven-week-old male Wistar rats were exposed to gastric I/R, and the gastric emptying rates at 12 and 48 h after I/R were evaluated by the phenol red method. Expressions of gene product of c-kit receptor tyrosine kinase (c-Kit), a marker of ICC, and of neuronal proteins were also examined. KEY RESULTS Gastric emptying was transiently delayed at 12 h after I/R, but returned to normal by 48 h. Expression of c-Kit protein as assessed by Western blotting and immunofluorescent staining of the smooth muscle layer, as well as expression of the mRNA of stem cell factor, the ligand for c-Kit, were reduced at both 12 and 48 h after I/R. The expression of neuronal nitric oxide synthase (nNOS) protein as assessed by Western blotting and immunofluorescent staining was also decreased at 12 h after I/R, but was restored to normal by 48 h. CONCLUSIONS & INFERENCES Gastric I/R evokes transient gastroparesis with delayed gastric emptying, associated with disruption of the ICC network and nNOS-positive neurons.
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Saeki N, Murai H, Hasegawa Y, Horiguchi K, Hanazawa T, Fukuda K. [Endoscopic endonasal surgery for extrasellar tumors: case presentation and its future perspective]. NO SHINKEI GEKA. NEUROLOGICAL SURGERY 2009; 37:229-246. [PMID: 19306643] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Endoscopic endonasal transsphenoidal surgery has been performed because of its advantages such as less invasive surgical management and more aggressive tumor removal of extrasellar lesions. In 2003, we began endoscope-assisting surgery. In 2006, we completely switched to the endoscopic endonasal approach without microscope or nasal specula. Today, we report endoscopic pituitary and skull base surgery in our institute. The endonasal approach via the sphenoid ostium was carried out without nasal specula. Postoperative nasal packing was basically not needed in such cases. In cases with meningiomas, craniopharyngiomas and giant pituitary adenomas, which needed intra-dural procedure, nasal procedures such as middle nasal conchotomy, posterior ethmoidectomy and skull base techniques such as optic canal decompression and removal of the planum sphenoidale were carried out to gain the wider operative field toward anterior skull base and lower clivus. Navigation and US-Doppler were essential. Angled endoscope attained more successful removal of tumor under direct visualization extending into the cavernous sinus (GH secreting ademomas) and lower clivus (chordoma). In the case of CSF (cerebrospinal fluid) leakage during operation, a newly designed balloon catheter was placed in the sphenoid sinus to fix the abdominal fat and fibrin glue at the leakage point. In recent cases, dural opening has been sutured. In the combination of such techniques, a lumbar drainage system to prevent postoperative CSF rhinorrhea became needless in many cases. Angled suction tips, single-shaft coagulation tools and slim and longer holding forceps, all of which were newly designed for endoscopic surgery, were essential for smoother procedure. Endonasal endoscopic pituitary surgery has resulted in less invasive transsphenoidal surgery since no postoperative nasal packing is needed and there is less dependency on lumbar drainage. Although better techniques to prevent postoperative CSF leakage needs to be developed, this endoscopic pituitary surgery will become more common and will become a standard procedure. Endoscopic skull base surgery has enabled more aggressive removal of extrasellar tumors with the aid of nasal and skull base techniques. This endoscopic skull base surgery is more highly specialized, needs special techniques and surgical training. Selection of patients is also important. This also needs collaboration with ENT (ear, nose, throat) doctors. To be acknowledged as a safe and successful procedure in skull base surgery, this complex procedure may be preferably carried out only in center hospitals, which deal with many patients with a skull base lesion.
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Aruga T, Suzuki E, Horiguchi S, Horiguchi K, Sekine S, Kitagawa D, Saji S, Funata N, Toi M, Kuroi K. A low number of tumor infiltrating FOXP3-positive cells after primary systemic chemotherapy is correlated with favorable relapse-free survival in breast cancer patients. Cancer Res 2009. [DOI: 10.1158/0008-5472.sabcs-5043] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Abstract #5043
Background: Cancer cells induce proliferation and local accumulation of immunosuppressive cells such as FOXP3-positive cells which known as regulatory T cells (Tregs). Tregs prevent the maturation of dendritic cells and their capacity to present tumor antigens to cytotoxic T lymphocytes (CTLs) and leads to tumor-induced tolerance. Although cancer chemotherapy was usually considered as immunosuppressive, some chemotherapeutic agents have recently been shown to activate an anticancer immune response, which is involved in the curative effect of these treatments. Therefore, we hypothesized that number of tumor infiltrating FOXP3-positive cells during primary systemic chemotherapy is correlated with therapeutic results in breast cancer patients.
 Methods: To test the hypothesis, between September 2000 and January 2005, breast cancer patients treated with primary systemic chemotherapy (PSC) (n=93) were included in the study. Three cases were excluded because main tumors were resected before PSC and three cases of pathological complete reaction were excluded because they were hard to define “tumor infiltrating” Tregs. To compare the number of FOXP3 positive cells in the tumors before and after PST, both core-needle biopsy (CNB) and surgical resected specimens were stained with FOXP3 monoclonal antibody. Numbers of tumor infiltrating FOXP3-positive cells were counted in 3 and 5 randomly chosen high power fields (CNB and surgical specimens, respectively). A median cutoff of >16.3 and > 6.6 defined patients with high numbers of Tregs (CNB and surgical specimens, respectively). We also divided the patients into four groups (high numbers of FOXP3 positive cells in both CNB and surgical specimens; HH, low numbers in the both specimens; LL, high numbers in CNB and low in the surgical specimens; HL, and low in CNB and high in surgical specimens; LH). All patients were treated with anthracyclin containing therapy and 79.3 %( n=69) of them were added taxanes sequentially.
 Results: In the tumors after PST, numbers of Tregs were significantly higher in lymphvessel invasion positive tumors (P=0.01) and ER negative tumors (P=0.02) but there was no correlation between lymph node involvement and numbers of Tregs (P=0.8). As for the comparison of four groups, LL group shows the longest relapse-free (P=0.04) and overall survival (P=0.09) and HH group shows the shortest relapse-free and overall survival among four groups. Interestingly, HL group shows better outcome than HH group and LH group shows worse one than LL.
 Conclusions: These findings suggest that the control of Tregs in the tumor is important for the control of the disease and Tregs might be an important therapeutic target for breast cancer. Furthermore, it is suggested that some chemotherapeutic agents could be a potential inhibitor of the Tregs in tumor and show antitumor effects addition to their direct cytotoxicity against cancer cells.
Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 5043.
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Horiguchi K, Tsutsui M, Kurokawa S, Sakai A. Electron transmission characteristics of Au/1,4-benzenedithiol/Au junctions. NANOTECHNOLOGY 2009; 20:025204. [PMID: 19417266 DOI: 10.1088/0957-4484/20/2/025204] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Electron transmission through individual 1,4-benzenedithiol molecules bridging between two gold electrodes (Au/BDT/Au junctions) has been studied by measuring the current-voltage (I-V) characteristics. Measurements were made at room temperature on three junction states of conductance 0.005G(0), 0.01G(0), and 0.1G(0), respectively, where G(0) is the quantum unit of conductance. All I-V curves are linear around zero bias and nonlinearly increase upward for biases above approximately 0.2 V. Absence of plateaus in the observed I-V characteristics up to +/- 1 V indicates that the electron transmission spectrum of Au/BDT/Au has no peaks within +/- 0.5 eV from the Fermi level.
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