[Show abstract][Hide abstract] ABSTRACT: Most primary breast cancers express estrogen receptor α and can be treated via endocrine therapy using anti-estrogens such as tamoxifen; however, acquired endocrine resistance is a critical issue. To identify tamoxifen response-related microRNAs (miRNAs) in breast cancer, MCF-7 cells infected with a lentiviral miRNA library were treated with 4-hydroxytamoxifen (OHT) or vehicle for 4 weeks, and the amounts of individual miRNA precursors that had integrated into the genome were evaluated by microarray. Compared to the vehicle-treated cells, 5 'dropout' miRNAs, which were downregulated in OHT-treated cells, and 6 'retained' miRNAs, which were upregulated in OHT-treated cells, were identified. Of the dropout miRNAs, we found that miR-574-3p expression was downregulated in clinical breast cancer tissues as compared with their paired adjacent tissues. In addition, anti-miR-574-3p reversed tamoxifen-mediated suppression of MCF-7 cell growth. Clathrin heavy chain (CLTC) was identified as a miR-574-3p target gene by in silico algorithms and luciferase reporter assay using the 3' untranslated region of CLTC mRNA. Interestingly, loss and gain of miR-574-3p function in MCF-7 cells causes CLTC to be upregulated and downregulated, respectively. These results suggest that functional screening mediated by miRNA libraries can provide new insights into the genes essential for tamoxifen response in breast cancer.
[Show abstract][Hide abstract] ABSTRACT: Optical imaging techniques for measuring tissue hemoglobin concentration have been recently accepted as a way to assess tumor vascularity and oxygenation. We investigated the correlation between early optical response to single-agent bevacizumab and treatment outcome.
PLoS ONE 06/2014; 9(6):e98715. · 3.53 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Purpose: Near-infrared diffuse optical spectroscopy (DOS) imaging can noninvasively measure tumor hemoglobin (Hb) concentration using high contrast to normal tissue, thus providing vascularity and oxygenation status. We assessed the clinical usefulness of DOS imaging in primary breast cancer.Materials and Methods: In all, 118 women with a histologically confirmed diagnosis of primary malignant tumor were enrolled. All participants underwent testing using time-resolved DOS before treatment initiation. Visual assessment of DOS imaging for detecting tumors was double-blindedly performed by two readers. Relative total Hb (rtHb) and oxygen saturation (stO2) of the tumors were compared with clinicopathological variables and 10-year prognosis was calculated.Results: Sensitivity for detecting a tumor based on the rtHb breast map was 62.7% (74/118). The sensitivity depended on T stage: 100% (7/7) for T3, 78.9% (45/57) for T2, 44.7% (17/38) for T1, and 31.3% (5/16) for Tis. Tumors showed unique features of higher rtHb with a wider range of stO2 than normal breast tissue, depending on a histological type. There was a significant correlation of rtHb with tumor size, lymphatic vascular invasion, and histological grade, and of stO2 with age and tumor size. Neither rtHb nor stO2 correlated with intrinsic biomarkers such as estrogen receptor, progesterone receptor, or HER2; rtHb inversely correlated with 10-year relapse-free survival and overall survival, with statistical significance.Conclusion: DOS imaging has limited utility for the early detection of breast cancer; nonetheless, the findings suggest that the degree of tumor angiogenesis and hypoxia may be associated with tumor aggressiveness and poor prognosis.This article is protected by copyright. All rights reserved.
[Show abstract][Hide abstract] ABSTRACT: Near-infrared optical imaging targeting the intrinsic contrast of tissue hemoglobin has emerged as a promising approach for visualization of vascularity in cancer research. We evaluated the usefulness of diffuse optical spectroscopy using time-resolved spectroscopic (TRS) measurements for functional imaging of primary breast cancer.
Fifty-five consecutive TNM stageI/II patients with histologically proven invasive ductal carcinoma and operable breast tumors (<5 cm) who underwent TRS measurements were enrolled. Thirty (54.5%) patients underwent 18F-fluoro-deoxy-glucose (FDG) positron emission tomography with measurement of maximum tumor uptake. TRS was used to obtain oxyhemoglobin, deoxyhemoglobin, and total hemoglobin (tHb) levels from the lesions, surrounding normal tissue, and contralateral normal tissue. Lesions with tHb levels 20% higher than those present in normal tissue were defined as "hotspots," while others were considered "uniform." The findings in either tumor type were compared with clinicopathological factors.
"Hotspot" tumors were significantly larger (P = 0.002) and exhibited significantly more advanced TNM stage (P = 0.01), higher mitotic counts (P = 0.01) and higher levels of FDG uptake (P = 0.0004) compared with "uniform" tumors; however, other pathological variables were not significantly different between the two groups.
Optical imaging for determination of tHb levels allowed for measurement of tumor vascularity as a function of proliferation and glucose metabolism, which may be useful for prediction of patient prognosis and potential response to treatment.
BMC Cancer 10/2013; 13(1):514. · 3.32 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Breast cancer is primarily a hormone-dependent tumor that is regulated by the status of the estrogen and progesterone receptors. We previously identified EBAG9 as an estrogen-responsive gene in MCF-7 human breast carcinoma cells. Upregulation of EBAG9 expression has been observed in several malignant tumors such as advanced breast cancers, indicating that EBAG9 might contribute to tumor progression.
In the present study, we generated a monoclonal antibody against EBAG9, and then performed immunohistochemical analysis of EBAG9 expression in specimens obtained from breast cancer patients treated with tamoxifen as an adjuvant therapy.
EBAG9 immunoreactivity was detected in the cytoplasm of breast cancer cells and was significantly elevated in breast cancer samples from patients who relapsed during or after adjuvant tamoxifen treatment. Positive EBAG9 immunoreactivity was significantly correlated with poor patient prognosis.
These results suggest that EBAG9 expression in tumor regions is associated with an unfavorable prognosis in breast cancer patients treated with tamoxifen.
Clinical Breast Cancer 10/2013; · 2.42 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We had previously reported a close association between pathological response and the maximum tumor standardized uptake value (SUVmax) measured by (18)F-fluorodeoxyglucose positron emission tomography prior to chemotherapy in estrogen receptor (ER)-positive breast cancer. We hypothesized that glucose hypermetabolism by luminal B tumors may result in chemotherapy responsiveness. Using a single-gene expression assay, TargetPrint® (Agendia) and a 70-gene expression classifier, MammaPrint® (Agendia), we divided 20 patients with ER-positive primary breast cancer into luminal A and luminal B subtypes and compared the tumor SUVmax value between the two groups. A significantly higher SUVmax was measured for luminal B tumors (n=10; mean±SD, 7.6±5.6) than for luminal A tumors (n=10; mean±SD, 2.6±1.2; p=0.01). Glucose hypermetabolism could help predict intrinsic subtyping and chemotherapy responsiveness as a supplement to ER, progesterone receptor, HER2, and Ki-67 histochemical scores.
Journal of Breast Cancer 09/2013; 16(3):342-4. · 1.32 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: We report a case of a trastuzumab-resistant human epidermal growth factor receptor-2(HER2)-positive breast cancer patient with extensive liver metastases and associated impaired liver function, who showed an excellent response to the combination of trastuzumab and capecitabine. The patient was a 59-year-old postmenopausal woman with multiple liver metastases at first examination. She first received anthracycline-based chemotherapy, and after progression was followed up with a combination of trastuzumab and paclitaxel. Despite an initial response to this treatment, liver metastases rapidly progressed. Although palliative treatment was considered because of her impaired liver function, she received capecitabine while continuing trastuzumab. This combination therapy showed an excellent response, and a good quality of life(QOL)was maintained for a long time without any severe adverse events. The continuation of trastuzumab is considered effective after having progressed by trastuzumab including pretreatment, and we consider it worth while to give a combination of trastuzumab and capecitabine to patients with extensive liver metastases and associated impaired liver function, because of the treatment's synergistic effect and low risk of causing severe adverse events.
Gan to kagaku ryoho. Cancer & chemotherapy 02/2013; 40(2):225-7.
[Show abstract][Hide abstract] ABSTRACT: Controversy surrounds the reliability of sentinel lymph node biopsy after primary systemic chemotherapy. In this study, we assessed axillary ultrasound for selecting patients most likely to optimally benefit from biopsy.
The study included 87 patients who received primary systemic chemotherapy and underwent a sentinel lymph node biopsy followed by axillary lymph node dissection. Lymph nodes >10 mm in diameter, irregularly swollen, round, and homogeneously hypoechoic without an echo-rich center were considered axillary ultrasound positive.
In axillary ultrasound-negative patients before and after primary systemic chemotherapy, identification, sensitivity, and false-negative rates were 81%, 100%, and 0%, respectively. However, in patients whose lymph nodes converted from positive to negative after primary systemic chemotherapy, these values were 83%, 70.8%, and 29.2%, respectively.
Axillary ultrasound-negative patients before and after primary systemic chemotherapy were suitable for sentinel lymph node biopsy. Axillary ultrasound should be used during primary systemic chemotherapy and before surgery.
American journal of surgery 04/2012; 204(4):487-93. · 2.36 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Breast cancer is primarily a hormone-dependent tumor that can be regulated by the status of the steroid hormones estrogen and progesterone. Forkhead box A1 (FOXA1) is a member of the forkhead box transcription factor family and functions as a pioneer factor of the estrogen receptor (ER) in breast cancer. In the present study, we demonstrate that FOXA1 mRNA was upregulated by estrogen and that estrogen receptor-α (ERα) recruitment to ER-binding sites in the vicinity of the FOXA1 gene was increased by estrogen in ERα-positive MCF-7 breast cancer cells. The estrogen-induced FOXA1 upregulation was repressed by 4-hydroxytamoxifen treatment. We also demonstrated that the proliferation and the migration of MCF-7 cells were decreased by FOXA1-specific small interfering RNA (siRNA; siFOXA1). Furthermore, siFOXA1 decreased the estrogen response element-driven transcription and the estrogen-dependent upregulation of ERα target genes in MCF-7 cells. Next, the immunohistochemical analyses of FOXA1 were performed using two groups of breast cancer specimens. The nuclear immunoreactivity of FOXA1 was detected in 80 (74%) of 108 human invasive breast cancers and was negatively correlated with tumor grade and positively correlated with hormone receptor status, including ERα and progesterone receptor, pathological tumor size, and immunoreactivity of FOXP1, another FOX family transcription factor. FOXA1 immunoreactivity was significantly elevated in the relapse-free breast cancer patients treated with tamoxifen. Notably, the double-positive immunoreactivities of FOXA1 and FOXP1 were significantly associated with a favorable prognosis for the relapse-free and overall survival of patients with tamoxifen-treated breast cancer, with lower P values compared with FOXA1 or FOXP1 immunoreactivity alone. These results suggest that FOXA1 plays an important role in the proliferation and migration of breast cancer cells by modulating estrogen signaling and that the double-positive immunoreactivities of FOXA1 and FOXP1 are associated with a favorable prognosis of tamoxifen-treated breast cancer.
[Show abstract][Hide abstract] ABSTRACT: Breast cancer stem cells are rich in triple negative or human epidermal growth factor receptor-2-positive breast cancers. The role of these stem cells in hormone receptor-positive breast cancers is unknown. Therefore, we launched this retrospective biomarker analysis to clarify the role of stem cells in relation with endocrine therapy in hormone receptor-positive breast cancer.
Formalin-fixed paraffin-embedded tissue samples from primary stage IV, hormone receptor-positive breast cancers prior to endocrine therapy were obtained from 4 cancer centers in Japan between 1999 and 2008. We examined the expression of ALDH1 and CD44/CD24 in breast tissue and correlated the results with response to endocrine therapy and patient prognosis.
ALDH1-positive and CD44+ CD24- cancer cells were found in 16% of 92 samples and 27% of 77 samples, respectively. Response to endocrine therapy was similar in the ALDH1-positive and ALDH1-negative tumor groups, and between CD44+ CD24- and other tumor groups. After a median follow-up period of 793 days, neither ALDH1 positivity nor CD44+ CD24- status of tumor cells was related to progression-free survival (ALDH1 positive vs. negative, 378 vs. 292 days, p = 0.53; CD44+ CD24- vs. others, 224 vs. 269 days, p = 0.52) or overall survival (ALDH1 positive vs. negative, 1,348 vs. 1,479 days, p = 0.17; CD44+ CD24- vs. others, 1,071 vs. 1,462 days, p = 0.54).
There is no correlation between biomarker expression and outcome in hormone receptor-positive breast cancer.
[Show abstract][Hide abstract] ABSTRACT: To assess whether the early metabolic response evaluated by (18)F-fluorodeoxy-glucose positron emission combined with computed tomography (FDG PET/CT) predicts the morphological, pathological, and cell-cycle responses to neoadjuvant endocrine therapy of hormone receptor-positive primary breast cancer.
Eleven patients (12 tumors) with estrogen receptor-positive (Allred score 7 or 8) primary breast cancer were enrolled. All patients received a daily dose (2.5 mg) of letrozole for 12 weeks followed by surgery. Sequential FDG PET/CT scans were performed before treatment (baseline), at 4 weeks after the initiation of endocrine therapy (PET2), and prior to surgery (PET3). Tumors showing a 40% or more reduction and those showing a less than 40% reduction in the standardized uptake value maximum (SUV(max)) at PET2 compared with the baseline PET were defined as metabolic responders and metabolic nonresponders, respectively. Change in tumor size as measured by ultrasound (morphological response), pathological response, and change in the Ki67 labeling index in tumor tissue (cell-cycle response) during the neoadjuvant letrozole therapy were compared between the metabolic responders and nonresponders.
The average decreases in SUV(max) at PET2 compared with the baseline PET in the metabolic responders (n = 6) and the metabolic nonresponders (n = 6) were 60.9% (±21.3 SD) and 14.2% (±12.0 SD), respectively. At PET3 compared with the baseline PET, the metabolic responders showed a significantly higher decrease of 64.5% (±18.7 SD) (p = 0.0004), whereas the nonresponders showed a nonsignificant decrease of 16.7% (±14.1 SD) (p = 0.06). The morphological and pathological responses after letrozole therapy did not differ between the metabolic responders and nonresponders. The metabolic responders showed a marked decrease in the Ki67 labeling index at 2 weeks after the initiation of treatment (62.9%, ±35.9 SD, p = 0.04) and at surgery (91.7%, ±10.7 SD, p = 0.03) compared with the baseline values. In contrast, metabolic nonresponders showed no significant change in the Ki67 index either after 2 weeks of therapy or at surgery.
Cell-cycle response monitored by the Ki67 labeling index correlates with metabolic response monitored by tumor SUV(max). Monitoring of tumor SUV(max) using FDG PET/CT may be feasible to predict cell-cycle response to neoadjuvant endocrine therapy of primary breast cancer.
Breast Cancer 10/2011; 18(4):299-308. · 1.51 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Breast cancer is primarily a hormone-dependent tumor that can be regulated by the status of steroid hormones, including estrogen and progesterone. Forkhead box P1 (FOXP1) is a member of the forkhead box transcription factor family and has been reported to be associated with various types of tumors. In the present study, we investigated the expression of FOXP1 in 133 human invasive breast cancers, obtained by core biopsy, by immunohistochemical analysis. Nuclear immunoreactivity of FOXP1 was detected in 89 cases (67%) and correlated positively with tumor grade and hormone receptor status, including estrogen receptor alpha (ERα) and progesterone receptor, and negatively with pathological tumor size. In ERα-positive MCF-7 breast cancer cells, we demonstrated that FOXP1 mRNA was upregulated by estrogen and increased ERα recruitment to ER binding sites identified by ChIP-on-chip analysis within the FOXP1 gene region. We also demonstrated that proliferation of MCF-7 cells was increased by exogenously transfected FOXP1 and decreased by FOXP1-specific siRNA. Furthermore, FOXP1 enhanced estrogen response element-driven transcription in MCF-7 cells. Finally, FOXP1 immunoreactivity was significantly elevated in relapse-free breast cancer patients treated with tamoxifen. These results suggest that FOXP1 plays an important role in proliferation of breast cancer cells by modulating estrogen signaling and that FOXP1 immunoreactivity could be associated with the estrogen dependency of clinical breast cancers, which may predict favorable prognosis in the patients treated with tamoxifen.
[Show abstract][Hide abstract] ABSTRACT: To assess the usefulness of positron emission tomography combined with computed tomography using (18)F-fluorodeoxyglucose (FDG PET/CT) for optimizing chemotherapy during neoadjuvant chemotherapy for primary breast cancer.
One hundred and eight patients (110 tumors) with breast cancer (≥2 cm, stages II and III) received neoadjuvant chemotherapy consisting of an anthracycline-based regimen and taxane. The maximal value of the baseline standardized uptake value (SUV) and the change in SUV after four cycles of an anthracycline-based regimen relative to baseline SUV were assessed for predicting pathological complete response (pCR) after sequential taxane.
Tumors with pCR had significantly higher baseline SUV (9.3 ± 3.7 SD) compared to those with non-pCR (7.2 ± 3.8 SD) (p = 0.02), but there was a considerable overlap between two groups. On PET scan after four cycles of chemotherapy, thirty-three patients (33.7%) with a 72.1% or greater reduction in SUV were considered as responders and the performance in predicting pCR had a sensitivity of 88.9% and specificity of 78.7%.
The baseline SUV could not be a useful indicator for predicting pCR due to the wide range in sensitivity. On the other hand, a relative change in SUV after completion of an anthracycline-based regimen could be useful for predicting pCR.
International Journal of Clinical Oncology 08/2011; 17(3):276-82. · 2.17 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: BACKGROUND: Sunitinib is a new tyrosine kinase inhibitor that has shown significant clinical activity in metastatic renal cell carcinoma (mRCC). We are reporting early clinical experiences of sunitinib at Akita University Hospital to evaluate its efficacy and safety for Japanese RCC patients. METHODS: Between April 2006 and November 2009 at our institution, 21 patients with a median age of 61 years (range, 37 to 80 years) with mRCC were treated with sunitinib. Eleven (52.4%) patients received sunitinib as a first-line treatment. The efficacy of sunitinib was evaluated with Response Evaluation Criteria In Solid Tumors (RECIST) guidelines. Progression-free survival (PFS) and adverse events (AEs) were assessed. RESULTS: At a median follow-up of 8 months (range, 1 to 43 months), our patients received an average of 6.2 cycles of sunitinib (range, 1 to 28 cycles). While no patients experienced complete response, partial response (PR) and stable disease (SD) were observed in 7 patients (28.5%) and 8 patients (38.0%), respectively; six patients (28.5%) had progressive disease (PD), median PFS was 10 months. The main grade 3/4 AEs were thrombocytopenia (47.6%), anemia (28.5%), leukocytopenia (19.0%), hand-foot syndrome (14.2%), and hypertension (14.2%). In addition to these AEs, hypothyroidism, which requires thyroid hormone replacement therapy, was noted in 14 (67.0%) patients. Seven patients discontinued sunitinib within 2 cycles (5 due to disease progression, 2 due to drug toxicities). Ten (66.7%) of 14 patients who received more than 3 cycles of sunitinib needed dose reduction during treatment. CONCLUSION: Sunitinib was effective for the treatment of mRCC in a real clinical setting, although there were several side effects that led to discontinuation of this drug. To utilize sunitinib safely and more effectively, further examination of this drug for Japanese RCC patients is necessary.
Japanese Journal of Clinical Oncology 03/2011; 41(3):i6-i17. · 1.75 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Breast cancer is primarily a hormone-dependent tumor that can be regulated by status of steroid hormones including estrogen and progesterone. Estrogen-related receptors (ERRs) are orphan nuclear receptors most closely related to estrogen receptor (ER) and much attention has been recently paid to the functions of ERRs in breast cancer in terms of the interactions with ER. In the present study, we investigated the expression of ERRγ in human invasive breast cancers by immunohistochemical analysis (n=110) obtained by radical mastectomy. Nuclear immunoreactivity of ERRγ was detected in 87 cases (79%) and tended to correlate with the lymph node status. No significant associations were observed with other clinicopathological characteristics, including the expression levels of both estrogen and progesterone receptors. In MCF-7 breast cancer cells, we demonstrated that ERRγ mRNA was up-regulated dose-dependently by estrogen, and that this up-regulation of ERRγ mRNA by estrogen was abolished by ICI 182,780 treatment. We also demonstrated that exogenously transfected ERRγ increased MCF-7 cell proliferation. Furthermore, ERRγ enhanced estrogen response element (ERE)-driven transcription in MCF-7 cells. In 293T cells, ERRγ could also stimulate ERE-mediated transcription with or without ERα. These results suggest that ERRγ plays an important role as a modulator of estrogen signaling in breast cancer cells.
The Journal of steroid biochemistry and molecular biology 09/2010; 123(1-2):1-7. · 3.98 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: A novel approach was introduced for breast surgery using the BiClamp, a new bipolar thermal energy device, to avoid complications and to shorten the time required for the dissection of the axillary lymph nodes.
Thirty-six patients with early breast cancer were assessed. The surgical parameters were compared between the procedures performed using the BiClamp technique (n = 14) and conventional surgery with suture ligation (n = 22). The parameters included the operation time, blood loss, and discharge on the first postoperative day. In addition, each of those parameters was compared between the patients with a high body mass index (BMI) (>22) and a low BMI (< or =22). The sealed vessels were examined histologically and heat-associated morphological vessel wall alterations were evaluated.
The operation time was significantly shorter in the BiClamp group than in the control group (P = 0.017, 90 +/- 18 vs 115 +/- 33 min). In addition, the blood loss in the BiClamp group tended to be smaller than in the control group, but the difference was not significant (P = 0.54, 61 +/- 47 vs 74 +/- 67 g). No other parameters showed any significant differences between the two groups.
The BiClamp thermofusion technique was safe and useful in breast surgery involving axillary dissection.
Surgery Today 08/2010; 40(8):706-10. · 1.21 Impact Factor
[Show abstract][Hide abstract] ABSTRACT: Recent advanced imaging modalities such as positron emission tomography (PET) detect malignancies using 2-[18F]-fluoro-2-deoxy-D: -glucose (18-FDG) with high accuracy, and they contribute to decisions regarding diagnosis, staging, recurrence, and treatment response. Here, we report a case of false-positive metastatic lymph nodes that were diagnosed by PET/CT and ultrasonography in a 48-year-old breast cancer patient who had undergone mastectomy. The tumors, which were oval shaped and resembled lymph nodes, were detected by ultrasonography. PET/CT revealed high uptake of 18-FDG in the tumors. To investigate the proposed recurrence and to re-evaluate the biology of the recurrent tumors, a tumor was removed from the brachial plexus of the patient. Histological findings revealed it to be a schwannoma. All imaging modalities including PET/CT failed to distinguish benign tumors from metastatic lymph nodes in the brachial plexus. After resection of the schwannomas, the patient complained of a slight motor disorder of the second finger on the right hand. Hence, it is important to consider a false-positive case of lymph node metastasis in a breast cancer patient following mastectomy.
Breast Cancer 07/2009; 18(2):141-4. · 1.51 Impact Factor