Unraveling the Mechanism of Cork Spot-like Physiological Disorders in 'Kurenainoyume' Apples Based on Occurrence Location

Cork spot-like physiological disorder (CSPD) is a newly identified issue in 'Kurenainoyume' apples, yet its mechanism remains unclear. To investigate CSPD, we conducted morphological observations on 'Kurenainoyume' apples with and without pre-harvest fruit-bagging treatment using light-impermeable paper bags. Non-bagged fruit developed CSPD in mid-August, while no CSPD symptoms were observed in bagged fruit. The bagging treatment significantly reduced the proportion of opened lenticels, with only 17.9% in bagged fruit compared to 52.0% in non-bagged fruits. In non-bagged fruit, CSPD spots tended to increase from the lenticels, growing in size during fruit development. The cuticular thickness and cross-sectional area of fresh cells in CSPD spots were approximately 16 µm and 1600 µm², respectively. Healthy non-bagged fruit reached these values around 100 to 115 days after full bloom from mid- to late August. Microscopic and computerized tomography scanning observations revealed that many CSPD spots developed at the tips of vascular bundles. Therefore, CSPD initiation between opened lenticels and vascular bundle tips may be influenced by water stress, which is potentially caused by water loss, leading to cell death and the formation of CSPD spots.

Visualization of ferroaxial domains in an order-disorder type ferroaxial crystal

Ferroaxial materials that exhibit spontaneous ordering of a rotational structural distortion with an axial vector symmetry have gained growing interest, motivated by recent extensive studies on ferroic materials. As in conventional ferroics (e.g., ferroelectrics and ferromagnetics), domain states will be present in the ferroaxial materials. However, the observation of ferroaxial domains is non-trivial due to the nature of the order parameter, which is invariant under both time-reversal and space-inversion operations. Here we propose that NiTiO₃ is an order-disorder type ferroaxial material, and spatially resolve its ferroaxial domains by using linear electrogyration effect: optical rotation in proportion to an applied electric field. To detect small signals of electrogyration (order of 10⁻⁵ deg V⁻¹), we adopt a recently developed difference image-sensing technique. Furthermore, the ferroaxial domains are confirmed on nano-scale spatial resolution with a combined use of scanning transmission electron microscopy and convergent-beam electron diffraction. Our success of the domain visualization will promote the study of ferroaxial materials as a new ferroic state of matter.

The presence of ferroaxial domain states is recently experimentally demonstrated by a nonlinear optical technique, which lacks high spatial resolution to visualize ferroaxial domains. Here, the authors visualize spatial distributions of ferroaxial domains in NiTiO₃ showing an order-disorder type ferroaxial transition.

Abstract OT2-01-01: Observational study of axilla treatment for breast cancer patients with 1 to 3 positive micrometastases or macrometastases in sentinel lymph nodes

[Background] Axilla surgery in node-positive breast cancer is dramatically changing from axillary lymph node dissection (ALND) to sentinel node biopsy (SNB). From the results of ACOSOG Z0011, IBCSG23-01 and AMAROS trials, adjuvant therapy and regional node irradiation could reduce regional lymph node recurrence for sentinel node-positive breast cancer patients. However, optimal indication of SNB alone remains uncertain. Trial design: To evaluate the outcome of sentinel node-positive breast cancer patients, the Japanese Society for Sentinel Node Navigation Surgery (SNNS) conducted a prospective cohort study in 2013 (UMIN000011782, Jpn J Clin Oncol, p.876-9, 2014). [Eligibility criteria] For eligible patients, SNB was performed or scheduled after 1 January 2012. Then 1 to 3 positive micrometastases or macrometastases in sentinel lymph nodes are confirmed by histological or molecular diagnosis. Primary chemotherapy before or after SNB is also acceptable for registration. [Specific aims] The primary endpoint is the 5-year recurrence rate of regional lymph node in patients treated with SNB alone. The secondary endpoint is the 5-year overall survival rate of this cohort. Patients treated with SNB followed by ALND are also registered simultaneously to compare the prognosis. The propensity score matching (PSM) is used to make the distributions of baseline risk factors comparable. [Statistical method] Based on an estimated recurrence rate of 5% at 5 years among patients treated with SNB alone, 240 patients are needed to give a 80% power to reject the null hypothesis that the recurrence rate is 10% with a one-sided type I error rate of 2.5%. If we consider that some patients will be lost to follow-up or become ineligible, a total of 250 patients will be needed to comprise the sample. [Present accrual] Eight hundred and eighty patients who underwent SNB alone or SNB followed by ALND were registered from 27 participating institutes between 2013 and 2016. Data cleaning is being performed. Patient's background and PSM will be reported.

Citation Format: Imoto S, Saito Oba M, Masuda N, Nagashima T, Wada N, Takashima T, Kitada M, Kawada M, Hayashida T, Taguchi T, Aihara T, Miura D, Toh U, Yoshida M, Sugae S, Yoneyama K, Matsumoto H, Jinno H, Sakamoto J. Observational study of axilla treatment for breast cancer patients with 1 to 3 positive micrometastases or macrometastases in sentinel lymph nodes [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr OT2-01-01.

Abstract P3-14-11: Comparative effectiveness of antiemetic regimens for highly emetogenic chemotherapy-induced nausea and vomiting: A systematic review and network meta-analysis

Background

The optimal choice of antiemetic therapy for chemotherapy-induced nausea and vomiting (CINV) needs to be clarified. This study assessed the efficacy and safety of antiemetic regimens for highly emetogenic chemotherapy (HEC).

Methods

Randomized trials that compared different antiemetic regimens were included from MEDLINE. Quality was assessed using the Cochrane risk-of-bias tool. We followed Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. Data were pooled using random-effects models. We conducted indirect comparisons using network meta-analysis of a Bayesian model. The main outcomes were the odds ratio (OR) for overall complete response (CR [i.e., no emesis and no rescue]). Safety was assessed from the trial description. All statistical tests were two-sided.

Findings

We systematically reviewed 24 randomized control trials (12,104 participants), which compared 12 different antiemetic regimens. Palonosetron (PAL) 0·75 mg (PAL0·75) + dexamethasone (Dex); aprepitant (APR) + a serotonin-3 receptor antagonist (5HT3) + Dex; and APR + PAL (0·25 mg or 0·50 mg) + Dex were more favorable than the reference regimen (OR, 1·51; 95% credibility interval [95%CrI], 1·18-1·91; OR, 1·78; 95%CrI, 1·58-2·05; and OR, 2·28; 95%CrI, 1·66-3·18, respectively). The oral combination of netupitant and palonosetron (NEPA) was more effective than conventional regimens (OR, 2·39; CrI, 1·73-3·30). Olanzapine (OLZ)-containing regimens were apparently the most effective: the ORs of OLZ + 5HT3 + Dex, OLZ + PAL + Dex, and OLZ + APR + 5HT3 + Dex were 2·78, 2·58, and 4·98, respectively.

Interpretation

The regimens of PAL0·75 + Dex, APR + 5HT3 + Dex, and APR + PAL + Dex were more favorable in conventional regimens (i.e., regimens without NEPA or OLZ), which support the NCCN guideline strategy. NEPA could be a better choice than conventional regimens. OLZ-containing regimens could be an optimal choice; thus, more trials need to be accumulated.

Citation Format: Yokoe T, Hayashida T, Nagayama A, Seki T, Takahashi M, Takano T, Abe T, Kitagawa Y. Comparative effectiveness of antiemetic regimens for highly emetogenic chemotherapy-induced nausea and vomiting: A systematic review and network meta-analysis [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-14-11.

Abstract P5-20-11: Comparative effectiveness of neoadjuvant therapy for HER2-Positive breast cancer: Addition of new clinical evidence to network meta-analysis and data update after 5 years

Background: It is becoming more popular to perform neoadjuvant chemotherapy including anti-HER2 agents to operable HER2-positive breast cancer patients. Increasing HER2-targeted treatment options urge us to define the best neoadjuvant therapy. In 2014, we reported the systematical assessment of the efficacy and safety of neoadjuvant therapy for HER2-positive breast cancer, using network meta-analysis based on Bayesian model (Nagayama et al., JNCI 2014). Network meta-analysis synthesizes information from a network of trials, which helps interpret the randomized evidence and can rank treatments from different trials. After five years from our first literature search, we decided to update our analysis due to accumulation of new clinical evidence.

Methods: We assessed odds ratio for pathological complete response (pCR), completion, and safety in seven treatment arms utilizing pooling effect sizes. The treatment arms included the combinations of chemotherapy (CT), trastzumab (tzmb), lapatinib (lpnb) and pertzumab (pzmb). All statistical tests were two-sided, and we followed Preferred Reporting Items for Systematic Reviews and MetaAnalyses (PRISMA) guidelines.

Results: A database search identified 993 articles with 13 studies meeting the eligibility criteria, adding three studies (a trial of CT + tzmb vs CT + lpnb, and two trials of CT + tzmb vs CT + lpnb vs CT + tzmb + lpnb) to previous analysis. In direct comparison, CT + tzmb significantly achieved more pCR than CT + lpnb (OR=0.68, 95% CI = 0.52 to 0.89, p=.005) despite no statistical difference was found previously. In indirect comparison, treatment arms of dual anti-HER2 agents with CT achieved more pCR than other arms, reducing their credibility intervals against all other arms. This trend was stronger in CT + tzmb + lpnb arm (CT + tzmb + lpnb vs CT + tzmb, OR = 1.62, 95% CrI = 1.19 to 2.22, p = .003), which we added sufficient clinical evidence. Moreover, it exposed the need for additional clinical data for pzmb relative arms. Values of surface under the cumulative ranking (SUCRA) suggested that CT + tzmb + pzmb had the highest probability of being the best treatment arm for pCR (SUCRA = 0.95), followed by CT + tzmb + lpnb (SUCRA = 0.87), and CT + tzmb (SUCRA = 0.62), widening the gap and differentiating the top two dual blockade arms which were close in our previous report. All outcomes from our present analysis were consistent with our previous report and strengthened data solidity by reducing confidence or credibility intervals.

Conclusion: Consistent results in not only in pCR but also in completion rates and adverse events indicate that we are looking at the results which are close to the truth. Additional trials of lpnb relative regimens are not probable to change the results, but pzmb relative trials are required to improve evidence solidity. New clinical data established stronger evidence in network meta-analysis that combining two anti-HER2 agents with CT is most effective in the neoadjuvant setting for HER2-positive breast cancer.

Citation Format: Nakashoji A, Hayashida T, Yokoe T, Maeda H, Watanuki R, Kikuchi M, Seki T, Takahashi M, Abe T, Kitagawa Y. Comparative effectiveness of neoadjuvant therapy for HER2-Positive breast cancer: Addition of new clinical evidence to network meta-analysis and data update after 5 years [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P5-20-11.

Abstract P2-01-37: Technical feasibility and validity of sentinel lymph node biopsy in patients with ipsilateral breast tumor recurrence

Background: The incidence of ipsilateral breast tumor recurrence (IBTR) was reported to be approximately 5-10% of breast cancer patients who had breast-conserving surgery. However, the role of sentinel lymph node biopsy (SLNB) in patients with IBTR still remains to be elucidated. The aim of this study wasto evaluate feasibility and validity of sentinel lymph node biopsy for ipsilateral breast tumor recurrence (second SLNB).

Patients and methods: A prospective database of 1607 patients with clinically node-negative breast cancer who underwent SLNB from January 2005 to May 2015 was analyzed and 46 patients with IBTR underwent SLNB. Lymphatic mapping was performed using a combined method of blue dye and radioisotope. ICG fluorescence imaging was performed in cases with failure of identification by blue dye and radioisotope.

Results: The median age was 52 (range: 36-82) years at the time of second SLNB and the mean size of recurrent tumor was 1.39 ± 0.63 cm. Thirty-one (67.4%) and 10 (21.7%) patients had a history of previous SLNB and axillary lymph node dissection (ALND), respectively. Another five (10.9%) patients had no previous axillary surgery for primary tumors. Preoperative lymphatic mapping by lymphoscintigraphy was successfully performed in 24 of 36 patients (66.7%). The identification rate by lymphoscintigraphy among patients with previous SLNB, ALND, and no axillary surgery was 64.0% (16/25), 66.6% (6/9) and 100% (2/2), respectively (P= 0.583). Overall, sentinel lymph nodes (SLNs) were successfully identified in 37 (80.4%) of 46 patients during surgery. The identification rate in patients with previous SLNB, ALND and no axillary surgery was 80.6% (25/31), 80.0% (8/10) and 80.0% (4/5), respectively (P=0.990). The aberrant lymphatic drainage to extra-ipsilateral axilla was found more frequently in patients with previous ALND compared with previous SLNB and no axillary surgery (40.0% vs. 6.5% vs. 0%, P=0.015).Among three (6.5%) patients with SLN metastases, one patient with previous SLNB had macrometastasis at the ipsilateral axilla and ALND found a positive non-SLN (1/21). The remaining two patients with previous SLNB and ALND had micrometastases at ipsilateral and contralateral axilla, respectively and both patients underwent no further axillary treatment. After second SLNB, systemic treatment including chemotherapy, endocrine therapy and trastuzumab was performed in 17 (37.0%), 36 (78.3%) and seven (15.2%) patients, respectively. No axillary recurrence was observed after a median follow-up time of 37.2 months from surgery for IBTR.

Conclusions: Second SLNB is technically feasible regardless of types of previous axillary surgery and may avoid complications from unnecessary ALND for IBTR. Furthermore, it could improve risk prediction for IBTR and provide valid information for deciding adjuvant therapy.

Citation Format: Matsumoto A, Jinno H, Yanagisawa T, Yoshikawa M, Takahashi Y, Seki T, Takahashi M, Hayashida T, Ikeda T, Kitagawa Y. Technical feasibility and validity of sentinel lymph node biopsy in patients with ipsilateral breast tumor recurrence [abstract]. In: Proceedings of the 2016 San Antonio Breast Cancer Symposium; 2016 Dec 6-10; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2017;77(4 Suppl):Abstract nr P2-01-37.

Comparison of oncological safety between nipple sparing mastectomy and total mastectomy using propensity score matching

INTRODCUTION

Although nipple sparing mastectomy (NSM) has attracted increased recognition as an alternative to traditional mastectomy approaches, its oncological safety is unclear. The purpose of this study was to compare the local recurrence rate between NSM and total mastectomy (TM).

METHODS

Between 2003 and 2013, 121 and 557 patients with stage 0-III breast cancer underwent NSM and TM respectively. Multivariate Cox regression and propensity score models were used to compare the two groups.

RESULTS

There was no significant difference in the five-year local recurrence rate between the NSM and TM groups (7.6% vs 4.9%, p=0.398). In multivariate analysis, NSM was not a risk factor for local recurrence (hazard ratio: 1.653, 95% confidence interval: 0.586-4.663, p=0.343). Propensity score matching found similar five-year local recurrence free survival rates between the two groups (92.3% vs 93.7%, p=0.655).

CONCLUSIONS

Our results suggest that NSM may provide oncological safety comparable with mastectomy for carefully selected patients.

Fate of aorta and clinical outcomes in patients with chronic type B aortic dissection: over 20-year experience

AIM

In type B double-barrel aortic dissection (AD), the fate of the affected aorta, causes of death, and very long-term clinical outcomes have not been completely elucidated. The purpose of this study was to clarify the fate of the affected aorta and long-term clinical outcomes in patients with type B AD during the chronic phase.

MEHODS

One hundred and four patients were entered into this study, and regular follow-up CT studies (mean; 87.6 months) were performed. Also, clinical data including AD-related events (including aneurysm formation, rupture, ischemia, and re-dissection), AD-related deaths, and long-term survival were retrospectively reviewed.

RESULTS

Forty-six of 104 patients (44.2%) had one more AD-related event during the follow-up period. The actuarial event-free rates for any AD-related events of all patients were 95±2%, 75±5%, 53±6%, and 13±7% at 1, 5, 10, and 20 years, respectively. Initial aortic diameter ≥40 mm and blood flow in the false lumen were significant risk factors for AD-related events in univariate and multivariate analysis.

CONCLUSION

In type B chronic aortic dissection, the affected aortas have a high incidence of AD-related events during the follow-up period. Prophylactic surgery or endovascular treatment for patients at high risk may reduce the AD-related events.

Hemoadsorption of high-mobility group box chromosomal protein 1 using a column for large animals

BACKGROUND

High-mobility group box chromosomal protein 1 (HMGB1) has recently been identified as an important mediator of various kinds of acute and chronic inflammation. A method for efficiently removing HMGB1 from the systemic circulation could be a promising therapy for HMGB1-mediated inflammatory diseases.

MATERIALS AND METHODS

In this study, we produced a new adsorbent material by chemically treating polystyrene fiber. We first determined whether the adsorbent material efficiently adsorbed HMGB1 in vitro using a bovine HMGB1 solution and a plasma sample from a swine model of acute liver failure. We then constructed a column by embedding fabric sheets of the newly developed fibers into a cartridge and tested the ability of the column to reduce plasma HMGB1 levels during a 4-hour extracorporeal hemoperfusion in a swine model of acute liver failure.

RESULTS

The in vitro adsorption test of the new fiber showed high performance for HMGB1 adsorption (96% adsorption in the bovine HMGB1 solution and 94% in the acute liver failure swine plasma, 2 h incubation at 37°C; p < 0.05 vs. incubation with no adsorbent). In the in vivo study, the ratio of the HMGB1 concentration at the outlet versus the inlet of the column was significantly lower in swine hemoperfused with the newly developed column (53 and 61% at the beginning and end of perfusion, respectively) than in those animals hemoperfused with the control column (94 and 93% at the beginning and end of perfusion, respectively; p < 0.05). Moreover, the normalized plasma level of HMGB1 was significantly lower during perfusion with the new column than with the control column (p < 0.05 at 1, 2, and 3 h after initiation of perfusion).

CONCLUSION

These data suggest that the newly developed column has the potential to effectively adsorb HMGB1 during hemoperfusion in swine.

Abstract P1-07-06: E2F-1 directly induces HOXB9 accelerating breast cancer progression

Homeobox B9 (HOXB9) is a member of the class I HOX genes with highly conserved 61 amino acid homedomain motif, known to be overexpressed in breast cancer and related to tumor angiogenesis, EMT (Hayashida et al., PNAS 2010), and radio-resistance (Chiba et al., PNAS 2011), being significant prognostic factor in breast cancer patients (Seki et al., Ann Surg Oncol 2012). In this study, we investigated how HOXB9 expression is regulated in breast cancer cells.

First, we analyzed the upstream promoter region of HOXB9 gene to determine the important sequence for HOXB9 transcription. The multiple lengths of HOXB9 promoter region from -2898 to +1 were cloned into pGL3 luciferase reporter vector. Luciferase activities in MDA-MB231 cells which overexpress HOXB9 were analyzed and determined that the region from -404 to -392 played the critical role for the transcription of HOXB9 gene. Computer prediction system for the binding ability to critical sequence raised several candidate genes including E2F-1, PAX-5, P53, Sp-I, ETS-1 and NFY-A which are known to be related with cancer progression. It was confirmed that all these genes could induce HOXB9 overexpression, and especially E2F-1 was the strong inducer. Then, E2F-1-induced cell lines from MCF7, MCF10A and MDA-MB231were established and the correlation between E2F-1 and HOXB9 mRNA expression was determined. ChIP assay revealed that E2F-1 could directly bind to the critical sequence of HOXB9 promoter. Electrophoretic Mobility Shift Assay (EMSA) also indicated the binding ability of E2F-1. Finally, the tissue samples of 141 breast cancer patients, who undertook breast cancer surgery as a primary treatment, were stained with E2F-1 and HOXB9 antibodies, and correlation between HOXB9 and E2F-1 expression was confirmed with statistical significance (p&lt;0.001).

There are many publications describe the E2F-1 relation to the breast cancer patients prognosis. The context of this research displays the direct dependence of HOXB9 gene's expression through E2F-1, which might be suppressed by specific treatment, for example CDK4/6 inhibitor, and improve breast cancer patients’ survival.

To confirm these genes might demonstrate novel factors and/or signaling pathways playing role in breast cancer progression through HOXB9 axis.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P1-07-06.

Abstract P6-06-43: Clinicopathological features of breast cancer patients with late recurrences

[Background]

With advances in early detection and improvements in treatments, long-term breast cancer survivors who had risk of late recurrence are increasing. Recent trials suggested 10 years of endocrine treatment produces a further reduction in recurrence and mortality rather than 5 years treatment. However, it remains to be elucidated which patients would have clinical benefit from longer endocrine treatment. We investigated clinicopathological features of breast cancer patients with late recurrences.

[Patients and Methods]

From 1989 to 2003, 1051 patients with primary breast cancer were treated at Keio University Hospital and classified into three groups: early recurrences (within 5 years), late recurrences (after 5 years) and no recurrences. Clinicopathological features of breast cancer patients with early and late recurrences were compared. Differences in frequency distribution were compared by the chi-squared test. Smoothed hazards estimates were used for estimation of recurrence rates depending on time.

[Results]

Among 1051 patients, 193 (18.4%) had early recurrences and 113 (10.8%) had late recurrences. Of all 306 recurrent patients, primary recurrent site was lung (24.2%), liver (8.8%), bone (20.0%), brain (1.3%), loco-regional (34.6%), distant lymph node (5.6%) and others (5.6%). Compared to patients with early recurrences, patients with late recurrences showed higher rate of positive hormone receptor (HR) status (58.0% vs. 81.4%, p&lt;0.001), lower rate of pathological nodal involvement (68.4% vs. 54.0%, p = 0.016), lower rate of lymphovascular invasion (LVI) (81.3% vs. 65.5%, p = 0.003) and smaller tumor size (2.99 cm vs. 2.46 cm, p = 0.005).

For node-positive patients, the hazard of estimates was similar between the HR-positive and HR-negative groups beyond 5 years. For node-negative patients, however, the hazard of HR-positive patients increased consistently, crossed with the hazard of HR-negative patients between 5 and 6 years and was higher than the hazard of HR-negative patients beyond 6 years.

Among 204 HR-positive recurrent patients, 112 (54.9%) had early recurrences and 92 (45.1%) had late recurrences. Compared to HR-positive patients with early recurrences, HR-positive patients with late recurrences had lower rate of pathological nodal involvement (71.4% vs. 55.4%, p = 0.026) and lower rate of LVI (81.3% vs. 66.3%, p = 0.023), however, tumor size was not significantly correlated with late recurrences of HR-positive patients. On the other hand, no clinicopathological factors including pathological nodal status, LVI and tumor size were significantly correlated with late recurrences among 102 HR-negative recurrent patients.

Among 193 patients with early recurrences, HR-positive patients had significantly longer post-recurrence survival than HR-negative patients (99.1 months vs. 60.0 months, p&lt;0.001). However, among 113 patients with late recurrences, post-recurrence survival of HR-positive patients was not significantly different from HR-negative patients (233.1 months vs. 231.2 months, p = 0.797).

[Conclusions]

These data suggested breast cancer patients with positive HR and negative nodal status had a high likelihood of developing late recurrences and should be treated with longer endocrine treatment.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P6-06-43.

Serine-204 in the linker region of Smad3 mediates the collagen-I response to TGF-β in a cell phenotype-specific manner

Regulation of TGF-β1/Smad3 signaling in fibrogenesis is complex. Previous work by our lab suggests that ERK MAP kinase phosphorylates the linker region (LR) of Smad3 to enhance TGF-β-induced collagen-I accumulation. However the roles of the individual Smad3LR phosphorylation sites (T179, S204, S208 and S213) in the collagen-I response to TGF-β are not clear. To address this issue, we tested the ability of Smad3 constructs expressing wild-type Smad3 or Smad3 with mutated LR phosphorylation sites to reconstitute TGF-β-stimulated COL1A2 promoter activity in Smad3-null or -knockdown cells. Blocking ERK in fibroblasts and renal mesangial cells inhibited both S204 phosphorylation and Smad3-mediated COL1A2 promoter activity. Mutations replacing serine at S204 or S208 in the linker region decreased Smad3-mediated COL1A2 promoter activity, whereas mutating T179 enhanced basal COL1A2 promoter activity and did not prevent TGF-β stimulation. Interestingly, mutation of all four Smad3LR sites (T179, S204, S208 and S213) was not inhibitory, suggesting primacy of the two inhibitory sites. These results suggest that in these mesenchymal cells, phosphorylation of the T179 and possibly S213 sites may act as a brake on the signal, whereas S204 phosphorylation by ERK in some manner releases that brake. Renal epithelial cells (HKC) respond differently from MEF or mesangial cells; blocking ERK neither changed TGF-β-stimulated S204 phosphorylation nor prevented Smad3-mediated COL1A2 promoter activity in HKC. Furthermore, re-expression of wild type-Smad3 or the S204A-Smad3 mutant in Smad3-knockdown HKC reconstituted Smad3-mediated COL1A2 promoter activity. Collectively, these data suggest that Serine-204 phosphorylation in the Smad3LR is a critical event by which ERK enhances Smad3-mediated COL1A2 promoter activity in mesenchymal cells.

Abstract P1-14-09: Immunohistochemical classification of intrinsic subtypes as a predictive biomarker of pathological compelete response in breast cancer patients treated with preoperative chemotherapy

Background: Analysis of gene expression arrays has resulted in the recognition of several fundamentally different subtypes of breast cancer. These subtypes have different natural histories and different responses to systemic and local therapies. However, widespread use of gene expression profiling is limited because of its expense and of technical difficulty. Alternatively, this classification has also been reproduced in immunohistochemical studies. The objective of this study was to evaluate the clinical utility of immunohistochemical classification of breast cancer intrinsic subtypes in the prediction of pathological compelete response (pCR) in a cohort of breast cancer patients receiving the sequential combination of taxane followed by anthracycline as preoperative chemotherapy.

Materials and methods: A prospective database of 150 women with stage II/ III breast cancer, who received neoadjuvant chemotherapy, was analyzed. The regimens were either four cycles of docetaxel (40 mg/m2 on day 1 every 3 weeks) with S-1 (80 mg/m2 on days 1–14 every 3 weeks) followed by four cycles of 5-fluorouracil (500 mg/m2), epirubicin (100 mg/m2) and cyclophosphamide (500 mg/m2) (FEC) or four cycles of docetaxel (60 mg/m2 on day 8 every 3 weeks) with capecitabine (1650 mg/m2 on days 1–14 every 3 weeks) followed by four cycles of FEC. Subtypes were classified into luminal A (lumA) (ER+ and/or PgR+, HER2−, Ki67&lt;14%), luminal B (lumB) (ER+ and/or PgR+, HER2−, Ki67&gt;14%), triple-positive (TP) (ER+ and/or PgR+, HER2+), HER2 (ER−, PgR−, HER2+), and triple-negative (TN) (ER−, PgR−, HER2−) by using immunohistochemically stained specimen obtained by core needle biopsy. Absence of invasive tumor cells in the breast at the time of surgery was defined as pCR.

Results: We found 34 women in lumA, 54 in lumB, 15 in TP, 8 in HER2, 33 in TN. The median age in each group was 53, 51, 50, 57 and 53 respectively (p = .397). The mean tumor size was 3.2cm, 3.5cm, 4.4cm, 3.9cm and 3.6cm respectively (p = .158). The clinical response rate measured by physical examination (calliper) was 80.6%, 93.9%, 86.7%, 100% and 82.4% (p = .378). pCR rate was 5.9%, 14.8%. 13.3%, 50%, 21.2% respectively (p = .031). The multivariate analysis showed ER negative, PgR negative and intrinsic subtype (TN) were the significant predictive factors of pCR (p = .027, p = .003, p = .004).

Conclusion: This study indicated that immunohistochemical classification of intrinsic subtype might be a useful predictive biomarker of pCR in breast cancer patients treated with preoperative chemotherapy.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P1-14-09.

Abstract P4-03-03: Feasibility study of a new volume navigation system-guided breast biopsy method for incidental enhancing lesions detected by breast contrast-enhanced magnetic resonance imaging

Background: Incidental enhancing lesions (IELs) undetected by conventional imaging such as mammography and ultrasonography (US) have been reported in 16–29% of patients undergoing subsequent breast contrast-enhanced magnetic resonance imaging (CE-MRI). We recently assessed IELs by performing breast biopsies using a volume navigation system (V-Navi) which synchronizse real-time US images with reconstructed CE-MRI data side-by-side on the same monitor. The aim of this retrospective study was to evaluate the feasibility of V-Navi-guided biopsy method as an IEL diagnostic procedure.

Methods: We performed breast biopsies on 333 patients after mammography, US and CE-MRI (GE Signa Excite HDx 1.5T, USA) examinations between January 2011 and May 2012 at Keio University Hospital. Patients with IELs detected by CE-MRI underwent a second-look US and a bilateral CE-MRI in the supine position in order to achieve the same position as in the US. CE-MRI data was then fused with real-time US images using a V-Navi (Logiq E9, GE Healthcare, USA). When an IEL was identified, we performed a V-Navi-guided vacuum-assisted needle biopsy (11G) or an excisional biopsy after V-Navi-guided marking.

Results: US-guided and stereo-guided breast biopsies were performed on 77.2% (257) and 16.8% (56) of the 333 patients, respectively. Twenty patients (6.0%) had IELs detected by CE-MRI and all such IELs were identified by the V-Navi. Sixteen (80%) of those 20 patients had IELs clearly detected by the V-Navi and underwent V-Navi-guided needle biopsies. The four remaining patients (20%) had IELs that were not clearly detected by the V-Navi and they underwent excisional biopsies. The median IEL size was 8.8mm (range, 5.0–48) and the median procedure time for V-Navi-guided needle biopsies was 42 minutes. No major complications were encountered in any of the cases. Histopathologically, nine IELs (45%) had malignant findings of invasive ductal carcinoma (5/20) and ductal carcinoma in situ (4/20) and 11 IELs (55%) had benign findings of fibrocystic disease (10/20) and intraductal papilloma (1/20).

Conclusion: The V-Navi-guided breast biopsy method was shown to be a safe and effective diagnostic method for the assessment of IELs detected by breast CE-MRI.

Pollen factors controlling self-incompatibility strength in Japanese pear

Japanese pear has a genetically controlled self-incompatibility system, but both the pollen-tube growth in a semi in vivo assay and fruit set after self-pollination differ considerably among cultivars. The percentage of styles in which pollen tubes have reached the base ranges from 0 to 36 %, a value determined by culture of styles in vitro, and fruit set ranges from 0.6 to 15.2 %. Based on these data, we have assigned a value for the self-incompatibility weakness to each cultivar. Here, we showed that pollen factors control the degree of self-incompatibility. When the pollen-tube growth of 13 cultivars was compared in a completely compatible 'Hougetsu' (S (1) S (7)) style, it differed a fair amount among cultivars and showed a significantly positive relation to self-incompatibility weakness (r = 0.707). The degree of self-incompatibility of pear is, therefore, determined by pollen factor(s) unrelated to the S-locus. Although the fruit set and fruit growth of 'Hougetsu' were not affected by the pollen donor, a positive relationship was also observed between seed number and self-incompatibility weakness (r = 0.972). However, in a style with no S-RNase production (genotype: S (4) (sm) S (4) (sm) ), the relationship disappeared (r = 0.341) and pollen-tube growth was promoted by 12-36 % except in one cultivar. These results suggest that S-RNase functions as a cytotoxin on compatible pollen in a cultivar-dependent manner, and that the degree of inhibition is determined by pollen factor(s) unrelated to the S-locus. The pollen factor also functions on S-RNase in incompatible styles, resulting in a different degree of self-incompatibility.

Increased plasma levels of high mobility group box 1 in patients with acute liver failure

BACKGROUND

High-mobility group box 1 (HMGB1) is a monocyte-derived late-acting inflammatory mediator, which is released in conditions such as shock, tissue injury and endotoxin-induced lethality. In this study, we determined the plasma and hepatic tissue levels of HMGB1 in patients with acute liver failure (ALF).

PATIENTS AND METHODS

We determined the plasma levels of HMGB1 and aspartate aminotransferase (AST) in 7 healthy volunteers (HVs), 40 patients with liver cirrhosis (LC), 37 patients with chronic hepatitis (CH), 18 patients with severe acute hepatitis (AH), and 14 patients with fulminant hepatitis (FH). The 14 patients with FH were divided into two subgroups depending upon the history of plasma exchange (PE) before their plasma sample collection. The hepatic levels of HMGB1 were measured in tissue samples from 3 patients with FH who underwent living-donor liver transplantation and from 3 healthy living donors. Hepatic tissue samples were also subjected to immunohistochemical examination for HMGB1.

RESULTS

The plasma levels of HMGB1 (ng/ml) were higher in patients with liver diseases, especially in FH patients with no history of PE, than in HVs (0.3 ± 0.3 in HVs, 4.0 ± 2.0 in LC, 5.2 ± 2.6 in CH, 8.6 ± 4.8 in severe AH, 7.8 ± 2.7 in FH with a history of PE, and 12.5 ± 2.6 in FH with no history of PE, p < 0.05 in each comparison). There was a strong and statistically significant relationship between the mean plasma HMGB1 level and the logarithm of the mean AST level (R = 0.900, p < 0.05). The hepatic tissue levels of HMGB1 (ng/mg tissue protein) were lower in patients with FH than in healthy donors (539 ± 116 in FH vs. 874 ± 81 in healthy donors, p < 0.05). Immunohistochemical staining for HMGB1 was strong and clear in the nuclei of hepatocytes in liver sections from healthy donors, but little staining in either nuclei or cytoplasm was evident in specimens from patients with FH.

CONCLUSION

We confirmed that plasma HMGB1 levels were increased in patients with ALF. Based on a comparison between HMGB1 contents in normal and ALF livers, it is very likely that HMGB1 is released from injured liver tissue.

P3-15-02: The Change of Bone Turnover Markers during Neoadjuvant Anastrozole Versus Exemestane: A Randomized Single-Center Study

Background: Non-steroidal aromatase inhibitors including anastrozole and letrozole have been reported to increase the rate of bone turnover, accelerate loss of bone, and increase the incidence of fractures. Although steroidal inactivator exemestane has similar inhibitory effect on the aromatization, animal studies have shown a weak but potentially important anabolic effect of exemestane metabolites, which might lead to decreased bone resorption. This randomized trial was conducted to compare the effect of exemestane and anastorozole on bone turnover markers.

Patients and Methods: Fifty-two postmenopausal women with ER-positive, HER2−negative, invasive, nonmetastatic, and operable breast cancer were randomly assigned to neoadjuvant exemestane (25 mg daily) or anastrozole (1 mg daily) for 4 months. The primary endpoint was change in bone turnover markers including resorption markers urinary and serum N-telopeptide (NTX) and the formation markers serum bone alkaline phosphatase (BAP). The secondary endpoint was tumor objective response (OR) assessed by both caliper and ultrasound. Comparisons were also made of breast conservation rate and adverse events.

Results: The changes in serum NTX from baseline to week 16 were not statistically different between anastrozole and exemestane. The changes in urinary NTX from baseline to week 16 were also not statistically different between both groups .BAP did not show any significant increase in the exemestane group (10.8%; p=0.21), whereas the increase in BAP from baseline to week 16 in the anastrozole group was 15.0% and marginally significant (p=0.05). There were no significant differences in OR in the intent-to-treat population between patients receiving anastrozole or exemestane (45.8% vs. 39.2%; p=0.63). The OR was similar between the patients with a baseline Ki67 index of ≥15% and &lt;15% in exemestane group (37.5% vs. 41.2%; p=0.86). In anastrozole group the OR in patients with a baseline Ki67 index of ≥15% and &lt;15% was 44.4% and 53.8%, respectively(p=0.66). Breast conservation rate was similar between anastrozole and exemestane (62.5% vs. 67.9%; p=0.68). Treatment was well tolerated and much the same for both groups.

Conclusions: There is no significant differences of the change in bone turnover markers between anastrozole and exemestane. These results indicate exemestane had no anabolic effects which would lead to fewer adverse effects on bone.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-15-02.

Loss of B-cell translocation gene 2 in estrogen receptor–positive breast cancer and tamoxifen resistance

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Background: The expression analysis in ER positive human breast cancer already demonstrated the loss of nuclear expression of BTG2, the cell cycle regulator, in 46% of tumors and showed a significant inverse correlation with cyclinD1 expression. Our analysis of Oncomine database suggested that BTG2 expression might be related to the clinical outcome in patients with tamoxifen treatment.

Methods: The examinations to evaluate whether BTG2 expression affects the sensitivity against tamoxifen were conducted both in vitro and in vivo.

Results: In vitro cellular proliferation assay using tamoxifen against ER positive cell lines revealed that T47D expressing high level of endogenous BTG2 showed more drug sensitivity than MCF7 expressing low level of BTG2. (MCF7; IC50=4.48uM, T47D; =1.31uM) Tetracycline-inducible BTG2 expression model was developed in MCF7 and the cellular proliferation was strongly inhibited by the concomitant administration of tetracyclin and tamoxifen in vitro. Then, the cell line was injected into the mammary fat pad of immunodeficient mice. After the tumors grew more than 125mm3, these tumor bearing mice were administered the water including tetracyclin and/or tamoxifen pellet for 3 weeks. Tumor growth ratio was significantly suppressed in the concomitant administration of tetracyclin and tamoxifen in comparison with the animal treated with single agent. (p=0.044) Consistently, tumor weight and Ki67 expression were also significantly suppressed in the mice administered both tamoxifen and tetracyclin. (BW; p=0.034, Ki67; p=0.039) The cohort of 60 patients treated with adjuvant tamoxifen monotherapy was available online. Comparison of disease-free survival (DFS) of patients with positive BTG2 expression versus patients with loss of BTG2 expression revealed an univariate association in the dataset (log-rank probability, p=0.029). Multivariate analysis indicated that BTG2 expression resulted an independent prognostic factor for DFS (HR, 0.69; 95% CI, 0.495 to 0.963; p=0.029).

Conclusions: Despite further validation studies need to be conducted, BTG2 expression may be useful biomarker to identify patients appropriate for tamoxifen treatment.

Relationship of BTG2 expression and anastrozole resistance in breast cancer

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Background: The B-cell translocation gene-2 (BTG2) belongs to a class of proteins known as the Tob and BTG antiproliferative protein family. It was shown that estrogen and progesterone suppress BTG2 expression for the development of mammary gland. We demonstrated that proliferation rate of low level BTG2 expression in MCF7 was strongly inhibited by the administration of tamoxifen. In postmenopausal breast cancer patients, androgens can be converted to mitogenic estrogens by aromatase in breast cancer cells. Based on these results, we hypothesized that BTG2 expression affects the sensitivity against aromatase inhibitior.

Methods: We used tetracycline-inducible BTG2 expression model in MCF7 stably transfected with the human aromatase gene (MCF7/tet/aro) as in vitro models of aromatase-driven breast cancer. The effects of BTG2 expression and administration of anastrozole in breast cancer cells were assessed by proliferation assays.

Results: Administration of androstendion increased 79.1% of cellular proliferation, suggested that introduced aromatase gene worked well. Elevated level of BTG2 mRNA expression by tetracycline treatment was confirmed by Quantitative-RTPCR. Anastrozole treatment (100nM) reduced 37.8% of cellular proliferation ability, whereas the concomitant administration of tetracycline and anastorozole reduced 59.0% of cellular proliferation. These results suggested that the inhibitory effect of anastrozol for cellular proliferation was enhanced under the condition of BTG2 expression.

Conclusions: Our results suggested loss of BTG2 expression may be affects the sensitivity against aromatase inhibitor.

HOXB9, a gene promoting tumor angiogenesis and proliferation, as a prognostic factor in breast cancer

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Background: We demonstrated that HOXB9, a member of homeobox genes, expression promoted tumor neovascularization and metastasis in vitro and in vivo assay. These findings imply that overexpression of HOXB9 contributes to tumor progression through activation of signaling pathways that alter both tumor-specific cell fates and tumor-stromal microenvironment, leading to increased invasion and metastasis. (Hayashida et al., PNAS 2010) We sought to determine whether these results could be extended to the clinical application. In this study, we evaluated the correlation between HOXB9 expression, clinical outcomes, and the clinicopathological variables in breast cancer patients, and the contribution of HOXB9 expression to tumor cell proliferation and angiogenesis.

Methods: A consecutive series of 141 patients with invasive ductal carcinoma who underwent surgical treatment were examined. HOXB9 protein expression was analyzed immunohistochemically using the anti-human HOXB9 polyclonal antibody. Immunostaining of Ki-67, CD31, and CD34 were performed to evaluate the association of proliferation and tumor angiogenesis with HOXB9 expression.

Results: Of 141 tumor specimens immunostained for HOXB9, 69 specimens (48.9%) were positive staining. Univariate logistic regression revealed ER and PgR negativity, HER2 positivity, high nuclear grade, and large pathological tumor size as significant variables associated with HOXB9 expression. Moreover, 12 (92.3%) out of 13 triple negative breast cancer showed HOXB9 expression. The disease-free survival (DFS) and the overall survival were significantly different between the HOXB9 positive and negative group; HR=20.714, p=0.001, HR 9.206, p=0.003, respectively. A Multivariate analysis indicated that HOXB9 expression was the only independent prognostic factor for DFS (HR=15.532, p=0.009). In subgroup analysis, HOXB9 positive tumors showed a significant increase in the number of vasculature and the Ki-67 ratio in comparison with HOXB9 negative.

Conclusions: Our results suggest that HOXB9 expression promoting the tumor proliferation and the angiogenesis is a significant prognostic factor in breast cancer.

A phase II neoadjuvant trial of concurrent trastuzumab and paclitaxel without anthracycline in women with HER2-positive operable breast cancer

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Background: Neoadjuvant paclitaxel plus trastuzumab followed by 5-fluorouracil, epirubicin, and cyclophosphamide plus trastuzumab revealed the high pathologic complete response (pCR) rate of up to 60% in patients with HER2-positive breast cancer. However, combination of trastuzumab and anthracycline has been associated with an increased incidence of cardiac dysfunction. The objective of this study was to determine the efficacy of concurrent administration of trastuzumab and paclitaxel without anthracycline as neoadjuvant chemotherapy. Predictive factors of pCR including deregulation of the phosphatidylinositol 3-kinase (PI3K) pathway were also investigated.

Methods: Patients with HER2-positive operable breast cancer received 12 cycles of weekly paclitaxel (80 mg/m2 IV) plus weekly trastuzumab (4mg/kg loading dose followed by 2 mg/kg IV) before surgery. PTEN status was evaluated by IHC with PTEN antibody (Thermo Scientific, CA). PTEN expression level was scored semiquantitatively based on staining intensity (0; no staining , 1+; reduced staining, and 2+; equal staining as compared to the internal control). PIK3CA mutation status was evaluated by sequencing of PIK3CA exons 9 and 20 using PCR amplification and direct sequencing. pCR was defined as no residual invasive carcinoma in the breast.

Results: Among 37 patients enrolled, ER and PgR were positive in 18 (48.6%) and 16 (43.2%) patients, respectively. The overall response rate was 86.5% (32/37) and the pCR rate was 48.6% (18/37). pCR rate was significantly correlated with PgR negativity (p=0.004) and higher Ki67 (p=0.01). PTEN loss was observed in 33.3% (8/24) of the tumor examined. PIK3CA sequence analysis of the 13 tumors identified 2 mutations in exon 20 and 2 mutations in exon 9, corresponding to a PIK3CA mutation frequency of 30.8%. PTEN loss and/or PIK3CA mutation were not significantly associated with pCR rate.

Conclusions: These data indicate that the combination of trastuzumab and paclitaxel without anthracycline is effective neoadjuvant chemotherapy with high pCR rate. PTEN loss and/or PIK3CA mutation were not useful predictors of resistance to trastuzumab.

Prognosis and non-sentinel lymph node status of the breast cancer patients with micrometastatic sentinel lymph nodes

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Background: Sentinel lymph node biopsy (SLNB) is a more sensitive and accurate nodal staging procedure than axillary lymph node dissection (ALND). Because of detailed pathologic evaluation in SLNs, more nodal micrometastases have been identified. However, it remains controversial whether to perform ALND for patients with micrometastases in SLNs and their prognostic significance is also a matter of debate. The purpose of this study is to determine the non-sentinel lymph node (NSLN) status and prognosis of the patients with micrometastatic SLNs.

Methods: A prospective database of 1,012 clinically node-negative, T1-T2 breast cancer patients, who underwent SLNB from January 2002 to Dec 2010 at Keio University Hospital was analyzed. SLNs were detected using a combined method of isosulfun blue dye and small-sized technetium-99m-labeled tin colloid. Intraoperative frozen examination was performed with hematoxylin and eosin (HE) staining. SLNs, fixed and embedded in paraffin, were additionally diagnosed with HE staining and immunohistochemical (IHC) analysis.

Results: Micrometastases in SLNs were found in 69 (6.8%) of 1,012 patients. Thirty eight (55.1%) of 69 patients with micrometastatic SLNs underwent immediate or delayed ALND and revealed no NSLN metastasis. Among 31 (44.9%) patients with micrometastatic SLNs who omitted ALND and axillary radiation therapy, no axillary lymph node recurrence has been observed after a median follow-up of 50 months, although 29 patients (93.5%) in these 31 patients received adjuvant systemic therapy. There is no significant difference in recurrence free survival between the patients with micrometastatic and negative SLNs (98.0% vs. 95.7%, respectively).

Conclusions: These date suggested that it may not be necessary to perform ALND for the patients with micrometastatic SLNs and the presence of micrometastases in SLNs may not worsen prognosis with proper systemic therapy.

Breast tumor progression induced by loss of BTG2 expression is inhibited by targeted therapy with the ErbB/HER inhibitor lapatinib

The B-cell translocation gene-2 (BTG2), a p53-inducible gene, is suppressed in mammary epithelial cells during gestation and lactation. In human breast cancer, decreased BTG2 expression correlates with high tumor grade and size, p53 status, blood and lymph vessel invasion, local and metastatic recurrence and decrease in overall survival, suggesting that suppression of BTG2 has a critical role in disease progression. To analyze the role of BTG2 in breast cancer progression, BTG2 expression was knocked down in mammary epithelial cells. Suppression of BTG2 enhances the motility of cells in vitro and tumor growth and metastasis in vivo. The effects of BTG2 knockdown are mediated through stabilization of the human epidermal growth factor receptor (HER) ligands neuregulin and epiregulin and activation of the HER2 and HER3 receptors, leading to elevated AKT phosphorylation. Suppression of HER activation using the tyrosine kinase inhibitor lapatinib abrogates the effects of BTG2 knockdown, including the increased cell migration observed in vitro and the enhancement of tumorigenesis and metastasis in vivo. These results link BTG2-dependent effects on tumor progression to ErbB receptor signaling, and raise the possibility that targeted inhibition of this pathway may be relevant in the treatment of breast cancers that have reduced BTG2 expression.

Abstract P5-10-13: Phase I Dose Escalation Study of Pirarubicin in Combination with Cyclophosphamide in Breast Cancer

Background: Doxorubicin containing combination chemotherapy regimens are widely used for treatment of breast and other cancers. However, these regimens are associated with significant toxicities including myocardialdysfunction and alopecia. Analogues of doxorubicin are being developed to reduce these side effects. Pirarubicin is a more lipophilic derivative of doxorubicin, with a higher uptake rate of cells, lower cardiotoxicity and better antitumor efficacy in preclinical models.

Purpose: We conducted a single-institution phase I clinical trial to determine the maximum-tolerated dose (MTD) and define the toxic effects and recommended dose (RD) of pirarubicin in combination with cyclophosphamide in patients with breast cancer. Patients and Methods: Patients who had received prior anthracycline therapy were excluded. Cohorts of three patients with breast cancer were treated with escalating doses of pirarubicin (40 to 70 mg/m2) intravenously administered every three weeks in combination with cyclophosphamide (60 mg/m2) for 4 or more cycles.

Results: Eleven patients of stage I/II operable breast cancer received a total of 46 cycles of pirarubicin and cyclophosphamide as post-operative adjuvant chemotherapy. The most frequently reported treatment-related grade 2 adverse events were constipation (36%) and nausea (27%). There were no grade 3/4 events. Grade 2 leukocytopenia and grade 2 fatigue were dose-limiting at 70 mg/m2, the maximum-tolerated dose was 60 mg/m2. Grade 2 alopecia was reported in 60 and 70 mg/m2 pirarubicin group. Conclusion: At the MTD of 60 mg/m2 every 3 weeks, pirarubicin in combination with cyclophosphamide was associated with mild, reversible toxicity. The recommended phase II dose is pirarubicin 50 mg/m2 and cyclophosphamide 60 mg/m2 on day 1 every 21 days.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P5-10-13.

Abstract P2-09-35: Differential Pathologic Response from Primary Systemic Chemotherapy across Breast Cancer Intrinsic Subtypes

Purpose: This study's purpose was to evaluate the clinical utility of breast cancer intrinsic subtypes in the prediction of pathological complete response (pCR) in a cohort of breast cancer patients receiving primary systemic chemotherapy.

Patients and Methods: Patients with stage II/III breast cancer received 4 cycles of XT (capecitabine 1650 mg/m2 on days 1-14 and docetaxel 60 mg/m2 on day 8 every 3 weeks), followed by 4 cycles of FEC (fluorouracil 500 mg/m2, epirubicin 90 mg/m2, cyclophosphamide 500 mg/m2 on day 1 every 3 weeks). Immunohistochemical analysis of estrogen receptor (ER), progesterone receptor (PgR), HER2, epidermal growth factor receptor (EGFR), cytokeratin (ck) 5/6, and Ki67 was performed in core needle biopsy samples at baseline. Tumors were classified as luminal A (ER+ and/or PgR+, and Ki67&lt;20%), luminal B(ER+ and PgR+, and Ki67≥20%), luminal-HER2 (ER+ and/or PgR+, and HER2+), HER2-enriched (ER-PgR-, and HER2+), or triple-negative (ER-, PgR-, and HER2-). Triple-negative tumors with and without EGFR+ and/or ck 5/6+ were further classified as basal-like and non-basal-like TN (NBTN), respectively. pCR was defined as no microscopic evidence of residual viable tumor cells, invasive or noninvasive, in all resected specimens of the breast. Results: Twenty-six (31.3%) patients were classified as luminal A, 12 (14.5%) were luminal B, 15 (18.1%) were luminal-HER2, 9 (10.8%) were HER2, 10 (12.0%) were basal-like, and 11 (13.3%) were NBTN. The overall response rate was 90.4%, including a complete response in 30 patients and a partial response in 45 patients. The overall pCR rate was 15.5% (12/83). The highest pCR rate (40.0%) was observed in patients with basal-like tumors. In triple-negative patients, basal-like patients showed significantly higher pCR rate than NBTN patients (40.0% vs. 9.1%, p=0.01). There were no cases with pCR in a cohort of luminal-HER2 subtype patients. A higher proportion of luminal B patients had pCR than luminal A patients (25.0% vs. 3.8%, p=0.01). With 33 months median follow-up, estimated 2-year disease-free survival for luminal A, luminal B, luminal-HER2, HER2, basal-like, and NBTN was 80.8%, 83.3%, 66.7%, 88.9%, 80.0%, and 81.8%, respectively.

Conclusions: Our data indicate that breast cancer subtypes are useful predictive biomarkers of pCR in breast cancer patients treated with primary systemic chemotherapy.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P2-09-35.

Abstract P4-07-07: HOXB9 Expression as a New Independent Prognostic Factor in Human Breast Cancer

Background: There are several reports showing a HOX gene family, which plays the critical roles for the differentiation during the embryonic stage, is associated with the tumorigenicity. It was demonstrated that HOXB9 is overexpressed in 42% of breast cancers, specifically those with high histological grade, and we defined the functional consequences of elevated HOXB9 expression in breast cancer. Moreover, HOXB9 expression promotes increased neovascularization and tumor metastasis to the lung in mouse xenograft models (Hayashida et al., PNAS, 2010). The puropose of this report is to evaluate the correlation between HOXB9 and clinicopathological variables in breast cancer patients. Patients and methods: A consecutive series of 141 patients with invasive ductal carcinoma who underwent surgical treatment at Keio University Hospital from January 2004 to January 2005 was involved. HOXB9 expression was analyzed immunohistochemically on formalin-fixed, paraffin-embedded tumor sections using rabbit anti-human HOXB9polyclonal antibody. Moreover, immunohistochemical stainings for Ki-67, CD31, and CD34 were also performed to evaluate the association with HOXB9 expression.

Results: The age at the diagnosis ranged from 30 to 93 years (median age, 58 years), and median observation period was 62.2 months. Of 141 tumor specimens immunostained for HOXB9, 69 specimens (48.9%) were positive staining. Univariate logistic regression revealed ER negativity (P&lt;0.001), PR negativity (P&lt;0.001), HER2 positivity (p=0.031), high nuclear grade (P&lt;0.001) and large pathological tumor size (p=0.002) as significant variables associated with HOXB9 expression. Notably, 12 (92. 3%) out of 13 triple negative breast cancer showed HOXB9 expression. The disease-free survival (DFS) at 5 year and the overall survival at 5 year were significantly different between the HOXB9 positive group and HOXB9 negative group; HR=8.5, 95%CI 3.3-21.9, p=0.001, HR 3.8, 95%CI 1.5-9.6, p=0.003, respectively. A Multivariate analysis indicated that HOXB9 expression was the independent prognostic factor for DFS (HR=14.1, 95% CI 1.851 to 107.4, p=0.011). Since HOXB9 expression accelerates the tumor angiogenesis in vitro and in vivo, we also evaluated the expression of vascular endothelial marker, CD31 and CD34 and cellular proliferation marker, Ki-67 in 45 patients with clinical T2 (tumor size, 2 to 5cm) tumor. In this subgroup analysis, HOXB9 positive patients (n=22) showed increased number of vasculature and Ki-67 ratio in comparison with HOXB9 negative patients (n=23) with statistical significance.

Correlations between HOXB 9 expression and Ki-67, CD31 and CD 34

Conclusion: The data identify HOXB9 expression as a new independent prognostic factor in breast cancer, which might help to improve the selection for appropriate therapy. Possibly, it might be useful to determine the application of anti-angiogenic therapy.

Abstract P1-11-04: A Phase II Preoperative Trial of Concurrent Trastuzumab and Paclitaxel without Anthracycline in HER2-Positive Operable Breast Cancer

Background

Concurrent trastuzumab with paclitaxel/fluorouracil, epirubicin, and cyclophosphamide (P/FEC) chemotherapy as neoadjuvant treatment revealed the high pathologic complete response (pCR) rate of 54.5% (Buzdar, 2007). Deregulation of the phosphatidylinositol 3-kinase (PI3K) pathway either through loss of PTEN or mutation of the catalytic subunit alpha of PI3K (PIK3CA) might confer resistance to trastuzumab. The objective of this study was to determine the efficacy of concurrent administration of trastuzumab and paclitaxel wtihout anthracycline as preoperative chemotherapy. The correlation between deregulation of PI3K and resistance to trastuzumab was also investigated. Patients & methods

Patients with HER2-positive, operable breast cancer received 12 cycles of weekly paclitaxel (80 mg/m2) and trastuzumab (4mg/kg loading dose then 2 mg/kg) for 12 weeks before surgery. PTEN status was evaluated by immunohistochemistry. PTEN staining intensity scores was recorded on an integer scale from 0 to 2+ (0; no staining, 1+; reduced staining, and 2+; equal staining as compared to the internal control). Sequencing of PIK3CA exons 9 and 20 was done by PCR amplification and direct sequencing. pCR was defined as no residual invasive carcinoma in the breast. Results

Twenty-eight patients were enrolled and assessable for clinical and pathologic responses. The overall response rate was 92.9%, including a complete response in 13 patients and a partial response in 13 patients. The pCR rate was 53.6% (15/28). Twenty-three patients (82.1%) underwent breast concerving surgery. Progesteron receptor (PgR) status was significantly correlated with pCR (p=0.025). Eight of 24 patients (33.3%) were scored PTEN negative. PIK3CA mutations were identified in 4 of 13 patients (30.8%). There was no significant difference in pCR rate and PTEN loss/PIK3CA mutation.

Correlation of PgR status and pCR

Conclusions

These data indicate that the combination of trastuzumab and paclitaxel without anthracycline is effective preoperative chemotherapy with high pCR rate. PTEN loss and/or PIK3CA mutation were not useful predictors of resistance to trastuzumab.