Remitting Seronegative Symmetrical Synovitis with Pitting Edema Syndrome as a Manifestation of Recurrent Ovarian Cancer

We herein report a case of ovarian cancer recurrence detected every time with symptoms of remitting seronegative symmetrical synovitis with pitting edema (RS3PE) syndrome. A 46-year-old woman who had a history of ovarian cancer 9 months earlier developed joint pain along with pitting edema in both hands and was diagnosed with RS3PE syndrome. Two and four years after initial surgery for ovarian cancer, symptoms of RS3PE syndrome appeared, and a recurrent site was detected. With resection of the relapsed sites and increased maintenance dose of methylprednisolone, these symptoms improved within a month.

Seronegative Full-house Nephropathy with Crohn's Disease

Systemic lupus erythematosus (SLE) is a chronic autoimmune inflammatory disease. Lupus nephritis (LN) is a major risk factor for mortality in SLE, and glomerular "full-house" immunofluorescence staining is a well-known characteristic of LN. However, some cases of non-lupus glomerulonephritis can also present with a "full-house" immunofluorescence pattern. We recently encountered a patient with full-house nephropathy (FHN) during adalimumab administration for Crohn's disease. IgA nephropathy or idiopathic FHN was diagnosed, and treatment with steroids was started, after which there was improvement in proteinuria. The prognosis of FHN has been reported to be poor; therefore, aggressive treatment is required for such patients.

OC-005 ENDOSCOPIC SURGICAL SKILL QUALIFICATION SYSTEM IN JAPAN: PROVEN PERFORMANCE IN HERNIA SURGERY

Endoscopic Surgical Skill Qualification System by Japan Society for Endoscopic Surgery is implemented from 2004.

Laparoscopic inguinal hernia repair (TAPP, TEP) is positioned as a low difficulty level operation under general surgery field in this system.

An application qualification to the system demands the list of a specified operative cases, to participate in education seminars, and training of endoscopic surgery over 2 years after the Board Certified.

A specified case quantity is the operative experience of above 5 examples of a high-difficulty level and 45 examples of a low difficulty level operation.

Candidates submit 3 no edited videos of the endoscopic surgery performed for indirect hernia with the orifice above 1.5 cm in a male-sex. Which to examine among 3 videos is decided randomly by the society.

Two hernia-specified referees examine one candidate. When both results don't agree, an extra referee will examine newly and fixes the result.

An evaluation is estimated within 60 points of common standards and 40 points by an hernia. Equal to or more than 70 points in amount become a pass. Acceptance rate in hernia was 16% in 2021.

The Nationwide Survey of Endoscopic Surgery reported recurrence rates of after laparoscopic hernia surgery as 5% in TEP in and 4% in TAPP in 2012–2013, 2.0% and 1.3% in 2018∼2019, what is improved beyond the period.

It's no exaggeration to say that the Qualification System has played a big part.

The Qualification System like no other in the world is to be introduced.

Short-term physical inactivity induces diacylglycerol accumulation and insulin resistance in muscle via lipin1 activation

Physical inactivity impairs muscle insulin sensitivity. However, its mechanism is unclear. To model physical inactivity, we applied 24-h hind-limb cast immobilization (HCI) to mice with normal or high-fat diet (HFD) and evaluated intramyocellular lipids and the insulin signaling pathway in the soleus muscle. Although 2-wk HFD alone did not alter intramyocellular diacylglycerol (IMDG) accumulation, HCI alone increased it by 1.9-fold and HCI after HFD further increased it by 3.3-fold. Parallel to this, we found increased protein kinase C ε (PKCε) activity, reduced insulin-induced 2-deoxyglucose (2-DOG) uptake, and reduced phosphorylation of insulin receptor β (IRβ) and Akt, key molecules for insulin signaling pathway. Lipin1, which converts phosphatidic acid to diacylglycerol, showed increase of its activity by HCI, and dominant-negative lipin1 expression in muscle prevented HCI-induced IMDG accumulation and impaired insulin-induced 2-DOG uptake. Furthermore, 24-h leg cast immobilization in human increased lipin1 expression. Thus, even short-term immobilization increases IMDG and impairs insulin sensitivity in muscle via enhanced lipin1 activity.NEW & NOTEWORTHY Physical inactivity impairs muscle insulin sensitivity. However, its mechanism is unclear. To model physical inactivity, we applied 24-h hind-limb cast immobilization to mice with normal or high-fat diet and evaluated intramyocellular lipids and the insulin signaling pathway in the soleus muscle. We found that even short-term immobilization increases intramyocellular diacylglycerol and impairs insulin sensitivity in muscle via enhanced lipin1 activity.

Abstract P3-09-05: Getting the most out of the 21-gene recurrence score assay: Increasing actionable results with a combined pathologic-genomic model

Introduction: The 21-gene recurrence score (RS) assay categorizes hormone receptor positive, node negative breast cancers (BC) into 3 risk groups for recurrence. We previously showed that the AAMC Model, using only standard pathology data, accurately does the same. This study compares the recurrence rate of the AAMC Model's risk groups to RS-based risk groups. A 2-step approach then is used, in which the AAMC model is applied first, and the RS assay is used only for AAMC intermediate risk cases. AAMC intermediate cases were reclassified by RS into low or high risk groups.

Methods: From a prospective registry of newly diagnosed BC, we selected invasive, hormone receptor positive, HER2 negative, lymph node negative cases from 2005 to 2015 tested with RS assay. Five-year Kaplan-Meier distant recurrence rates were calculated for each risk category.

Results: 1268 cases were included. Five-year recurrence rates were similar between the AAMC Model's low risk group and RS<18 low risk group, as well as between the AAMC Model's high risk group and the RS>30 high risk group. Applying the RS assay to the 715 cases in the AAMC Model's intermediate group resulted in re-classifying 417 (58%) as low risk and 41 (6%) as high risk. Using RS alone, 33% of cases were intermediate risk (n=424), whereas in the 2-step approach 20% were intermediate risk (n=257). For the 2-step approach, the 5-year distant recurrence rate was 3.3% for the low risk group (n=740) and 24.4% for the high risk group (n=271).

Conclusions: Five-year recurrence rates in the AAMC Model's low and high risk groups were similar to those in RS-based risk groups. The 2-step approach, with RS used only for AAMC intermediate cases, resulted in larger low and high risk groups with equivalent prognostic accuracy, compared to use of the RS assay alone. The 2-step approach reliably identifies a large number of patients unlikely to benefit from 21 gene assay and provides substantial cost savings.

Kaplan-Meier Calculated 5-year Distant Recurrences Rates for 4 Models: 1268 Patients Oncotype DXTAILORxAAMC Model2 Step Model with OncotypeDX for AAMC IntermediatesLow RiskRS < 18 (n=703)RS < 11 (n=250)Grade 1 and PR ≥ 1% (n=323)AAMC Low or AAMC intermediate/RS <18 (n=740) 3.4% (95% CI 1.6 – 5.1%, nf=17)4.0% (95% CI 0.8 – 7.2%, nf=8)2.7% (95% CI 0.0 – 5.4%, nf=5)3.3% (95% CI 1.4 – 5.2%, nf=16)Intermediate RiskRS 18 - 30 (n=424)RS 11 - 25 (n=787)Not meeting AAMC definition for low or high risk (n=715)AAMC Intermediate and RS 18-30 (n=257) 15.2% (95% CI 10.3 – 20.1%, nf=38)7.3% (95% CI 4.7 – 9.9%, nf=35)8.4% (95% CI 5.4 – 11.3%, nf=36)12.0% (95% CI 5.8 – 18.1%, nf=15)High RiskRS > 30 (n=141)RS > 25 (n=231)Grade 3 or ER < 20% (n=230)AAMC High or AAMC intermediate/RS > 30 (n=271) 23.0% (95% CI 14.7 – 31.3%, nf=27)22.9% (95% CI 15.9 – 29.9%, nf=39)22.8% (95% CI 16.1 – 29.5%, nf=41)24.4% (95% CI 18.0 – 30.7%, nf=51)RS= Recurrence Score, nf=number of recurrences, CI = confidence interval.

Citation Format: Mylander C, Rosman M, Gage M, Fujii T, Le Du F, Raghavendra A, Sinha A, Espinosa Fernandez JR, James A, Ueno N, Tafra L, Jackson R. Getting the most out of the 21-gene recurrence score assay: Increasing actionable results with a combined pathologic-genomic model [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 P3-09-05.

Hole-phonon coupling effect on the band dispersion of organic molecular semiconductors

The dynamic interaction between the traveling charges and the molecular vibrations is critical for the charge transport in organic semiconductors. However, a direct evidence of the expected impact of the charge-phonon coupling on the band dispersion of organic semiconductors is yet to be provided. Here, we report on the electronic properties of rubrene single crystal as investigated by angle resolved ultraviolet photoelectron spectroscopy. A gap opening and kink-like features in the rubrene electronic band dispersion are observed. In particular, the latter results in a large enhancement of the hole effective mass (> 1.4), well above the limit of the theoretical estimations. The results are consistent with the expected modifications of the band structures in organic semiconductors as introduced by hole-phonon coupling effects and represent an important experimental step toward the understanding of the charge localization phenomena in organic materials.The charge transport properties in organic semiconductors are affected by the impact of molecular vibrations, yet it has been challenging to quantify them to date. Here, Bussolotti et al. provide direct experimental evidence on the band dispersion modified by molecular vibrations in a rubrene single crystal.

Receptor clustering and activation by multivalent interaction through recognition peptides presented on exosomes

We demonstrate a novel system for inducing clustering of cell surface receptors via recognition peptide segments displayed on exosomes, leading to receptor activation. With this system, targeting of receptor-expressing cells and facilitation of the endocytic uptake of exosomes, which contained the anti-cancer protein saporin, were successfully achieved, leading to cell death.

PU.1 acts as tumor suppressor for myeloma cells through direct transcriptional repression of IRF4

We previously reported that PU.1 is downregulated in the majority of myeloma cell lines and primary myeloma cells of certain myeloma patients, and conditional expression of PU.1 in such myeloma cell lines induced cell cycle arrest and apoptosis. We found downregulation of IRF4 protein in the U266 myeloma cell line following induction of PU.1. Previous studies reported that knockdown of IRF4 in myeloma cell lines induces apoptosis, prompting us to further investigate the role of IRF4 downregulation in PU.1-induced cell cycle arrest and apoptosis in myeloma cells. PU.1 induced downregulation of IRF4 at the protein level, cell cycle arrest and apoptosis in six myeloma cell lines. Chromatin immunoprecipitation (ChIP) revealed that PU.1 directly binds to the IRF4 promoter, whereas a reporter assay showed that PU.1 may suppress IRF4 promoter activity. Stable expression of IRF4 in myeloma cells expressing PU.1 partially rescued the cells from apoptosis induced by PU.1. As it was reported that IRF4 directly binds to the IRF7 promoter and downregulates its expression in activated B cell-like subtype of diffuse large B cell lymphoma cells, we performed ChIP assays and found that IRF4 directly binds the IRF7 promoter in myeloma cells. It is known that IRF7 positively upregulates interferon-β (IFNβ) and induces apoptosis in many cell types. Binding of IRF4 to the IRF7 promoter decreased following PU.1 induction, accompanied by downregulation of IRF4 protein expression. Knockdown of IRF7 protected PU.1-expressing myeloma cells from apoptosis. Furthermore, IFNβ, which is a downstream target of IRF7, was upregulated in myeloma cells along with IRF7 after PU.1 induction. Finally, we evaluated the mRNA expression levels of PU.1, IRF4 and IRF7 in primary myeloma cells from patients and found that PU.1 and IRF7 were strongly downregulated in contrast to the high expression levels of IRF4. These data strongly suggest that PU.1-induced apoptosis in myeloma cells is associated with IRF4 downregulation and subsequent IRF7 upregulation.

Abstract OT2-01-22: NCT02456857: A phase II trial of liposomal doxorubicin, bevacizumab and everolimus (DAE) in patients (pts) with localized triple-negative breast cancer (TNBC) with tumors predicted insensitive to standard neoadjuvant chemotherapy (NACT)

BACKGROUND: Approximately 50% of TNBC pts treated with standard taxane/anthracycline-based NACT will have chemo-insensitive disease (CID) manifested as extensive residual disease (RCB-II or III) at the time of surgery. 40-80% of these pts will develop recurrence within 3 years of initial diagnosis. Recent advances in molecular profiling have identified subsets of TNBC with distinct, targetable molecular features. We developed a clinical trial to identify and characterize CID (ARTEMIS: A Randomized, TNBC Enrolling trial to confirm Molecular profiling Improves Survival). In the ARTEMIS trial, treatment naïve pts with localized TNBC undergo a pretreatment biopsy and then immediately start their initial phase of anthracycline-based chemotherapy so that the results of the molecular characterization are used in combination with response assessment (clinical exam/diagnostic imaging) to identify CID and inform the second phase of NACT, thus using a 'second hit' strategy in the middle of NACT to overcome drug resistance. The mesenchymal subtypes of TNBC have a high incidence of PI3K pathway activation. Preclinical models demonstrated response to PI3K inhibitors in this subtype. Metaplastic breast cancers make up ∼30% of tumors characterized as 'claudin-low/mesenchymal' by gene signature and are also associated with a high rate of PI3K activating molecular aberrations. A combination regimen of liposomal doxorubicin, bevacizumab and the mTOR inhibitors temsirolimus or everolimus (DAT or DAE) demonstrated response (including durable complete responses) in metastatic metaplastic breast cancer.

PRIMARY OBJECTIVE: Determine the rate of pathologic complete response (pCR/RCB-0) or minimal residual disease (RCB-I) after 4 cycles of DAE for treatment of mesenchymal TNBC deemed to be CID through the ARTEMIS trial

TRIAL DESIGN AND STATISTICAL METHODS: Only pts deemed to have mesenchymal CID on the ARTEMIS trial can enter this non-randomized phase II study. Realizing that pts without response to their initial cycles of chemotherapy have very low chance (5%) of achieving pCR with additional cycles of chemotherapy, it would be clinically meaningful to see pCR in this pt population improved to 20%. Counting pCR (RCB-0) or RCB-I as response, a two-stage Gehan-type design will be employed with 14 pts in the first stage. If at least one pt responds, 23 more pts will be added for a total of 37 pts. This design has a 49% chance of terminating after the first stage if the true response rate is 0.05, 23% chance if the true rate is 0.10, 10% if the true rate is 0.15 and 4% if the true rate is 0.20. If accrual continues to the second stage and a total of 37 pts are enrolled, the 95% confidence interval for a 0.20 response rate will extend from 0.10 to 0.35.

BRIEF ELIGIBILITY CRITERIA: Inclusion: localized TNBC enrolled onto ARTEMIS trial, adequate organ, bone marrow and cardiac parameters Exclusion: metastatic disease, pregnant or lactating pts, medical illness that increases chance of moderate to severe toxicity

CORRELATIVE SCIENCE: Correlate vimentin expression by IHC, mesenchymal signatures and PI3K pathway aberrations with response.

Citation Format: Moulder S, Hess K, Rauch M, Astrada B, Litton J, Mittendorf E, Ueno N, Tripathy D, Lim B, Piwnica-Worms H, Thompson A, Symmans WF. NCT02456857: A phase II trial of liposomal doxorubicin, bevacizumab and everolimus (DAE) in patients (pts) with localized triple-negative breast cancer (TNBC) with tumors predicted insensitive to standard neoadjuvant chemotherapy (NACT) [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 OT2-01-22.

Abstract P3-16-01: Immune characterization of inflammatory breast cancer and correlation to pathological complete response

Background:

Treatment of inflammatory breast cancer (IBC) includes neoadjuvant chemotherapy (NAC) followed by mastectomy and radiation. Responses are limited however with low pathological complete response (pCR) rates and poor survival. Recent RNA expression studies suggest that activated T cell signaling pathways and immunomodulatory markers such as PD-L1 are associated with a higher pCR rate in IBC; however comprehensive studies of tumor infiltrating lymphocytes (TIL) and protein expression of immunomodulatory molecules are lacking. There is a critical need therefore to study molecular and immune determinants of therapeutic response in IBC, with the goal of identifying biomarkers and actionable strategies to improve treatment outcomes.

Methods:

Baseline core biopsies from 36 IBC patients, 22 with stage III and 14 with stage IV disease were evaluated. Of these, 21 stage III and 10 stage IV patients underwent mastectomy following NAC, the latter for palliative purposes. Tumor subtype distribution was 14 patients with HER2-/HR-, 6 with HER2+/HR-, 11 with HER2-/HR+, and 5 with HER2+/HR+ disease. TIL infiltration in the tumor stroma was quantified on H&E slides based on consensus guidelines as well as by immunohistochemistry (IHC) staining for CD8. PD-L1 expression in the TIL and invasive tumor was evaluated by IHC in tumors with >1%TIL.

Results:

Stromal TIL were found in the invasive tumor on pretreatment biopsies in 26 (72%) patients, with TIL percentages ranging from 1% to 60% (mean=11.6; sd=13.8); of note, 1 patient biopsy sample only had tumor emboli on the tissue block and therefore was not evaluable. Higher TIL infiltrate was noted in stage III versus stage IV disease (mean TIL 11.6% versus 3.5%, p=0.028). Mean TIL infiltrate was 11.5% in HER2-/HR-, 10.0% in HER2+/HR-, 10.4% in HER2+/HR+, and 3.6% in HER2-/HR+ tumors (p=NS). At mastectomy, 7/21 stage III patients and 1/10 stage IV patients achieved a pCR. Mean TIL was 13.4% in the pCR group versus 8.2% in the non-pCR group (p=0.37) CD8 and PD-L1 staining was performed on samples with >1%TIL (n=15, of which 14 samples were available for additional staining). An average of 42% of TIL stained positive for CD8 (range 10-80%). There was no significant relationship between %CD8 and pCR, stage, or receptor status. None of these 14 patients demonstrated membranous PD-L1 positivity but all had focal weak cytoplasmic staining in the lymphocytes.

Conclusions:

Differences exist in the presence of stromal TIL in distinct groups within IBC (stage III versus stage IV disease and across histologic subtypes) and may contribute to differential responses to therapy. When comparing these results to published non-IBC literature (FinHER trial), our IBC patient cohort had lower TIL infiltrate in several histologic subtypes (HER2-/HR- 11.5% vs 25%, p=0.015), HER2+/HR-(10% vs 20%, p=0.10), and HER-/HR+ disease (3.6 vs 7.5%, p=0.01); TIL was comparable for HER2+/HR+ disease. Additional studies are underway (including multiplex analysis of myeloid and lymphoid markers, T cell receptor sequencing, and molecular profiling) in pre-treatment and surgical samples to better understand mechanisms of treatment response and resistance.

Citation Format: Reddy SM, Wargo JA, Reuben A, Reuben J, Woodward W, Ueno N, Mittendorf EA, Krishnamurthy S. Immune characterization of inflammatory breast cancer and correlation to pathological complete response [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 P3-16-01.

Has racial difference in cause-specific death improved in older patients with late-stage breast cancer?

BACKGROUND

Research on temporal mortality trends for stage IV breast cancer is limited, especially among older patients by race. We evaluated factors associated with overall, breast cancer-specific and other-cause mortalities using contemporary population data.

PATIENTS AND METHODS

Using the Surveillance, Epidemiology, and End Results-Medicare linked data, we identified older women (≥ 66 years) with stage IV breast cancer diagnosed in 2002-2009. Overall mortality was estimated by the Kaplan-Meier method, compared by log-rank tests, and modeled by Cox models. Competing risk analysis was used to evaluate breast cancer-specific and other-cause mortalities.

RESULTS

The median overall survival time for non-Hispanic blacks improved from 8.6 months in 2002-2003 to 9.9 months in 2007-2009, whereas that for non-Hispanic whites improved from 12.1 to 14.8 months. In the multivariate model, the risk of breast cancer-specific death for patients diagnosed in 2007-2009 was significantly lower (P = 0.02), whereas the risk of other-cause mortality changed little (P = 0.88) compared with those risks for patients diagnosed in 2002-2003. Non-Hispanic blacks had the higher risk of both mortality types compared with non-Hispanic whites; a diagnosis time-race interaction term was not statistically significant for either cause of death.

CONCLUSION

Breast cancer-specific mortality among older women modestly improved from 2002 to 2009 across all races, but not other-cause mortality. Racial disparity in mortality persisted, but did not widen in this period. Efforts should be devoted to improving other-cause mortality for all women, with special attention toward decreasing breast cancer mortality for non-Hispanic black women.

INPP4B Is a PtdIns(3,4,5)P3 Phosphatase That Can Act as a Tumor Suppressor

Inositol polyphosphate 4-phosphatase B (INPP4B) has been identified as a tumor suppressor mutated in human breast, ovary, and prostate cancers. The molecular mechanism underlying INPP4B's tumor-suppressive role is currently unknown. Here, we demonstrate that INPP4B restrains tumor development by dephosphorylating the PtdIns(3,4,5)P3 that accumulates in situations of PTEN deficiency. In vitro, INPP4B directly dephosphorylates PtdIns(3,4,5)P3. In vivo, neither inactivation of Inpp4b (Inpp4b(Δ/Δ)) nor heterozygous deletion of Pten (Pten(+/-)) in mice causes thyroid abnormalities, but a combination of these mutations induces malignant thyroid cancers with lung metastases. At the molecular level, simultaneous deletion of Inpp4b and Pten synergistically increases PtdIns(3,4,5)P3 levels and activates AKT downstream signaling proteins in thyroid cells. We propose that the PtdIns(3,4,5)P3 phosphatase activity of INPP4B can function as a "back-up" mechanism when PTEN is deficient, making INPP4B a potential novel therapeutic target for PTEN-deficient or PIK3CA-activated cancers.

SIGNIFICANCE

Although INPP4B expression is reduced in several types of human cancers, our work on Inpp4B-deficient mice provides the first evidence that INPP4B is a bona fide tumor suppressor whose function is particularly important in situations of PTEN deficiency. Our biochemical data demonstrate that INPP4B directly dephosphorylates PtdIns(3,4,5)P3.

microRNA-18a induces apoptosis in colon cancer cells via the autophagolysosomal degradation of oncogenic heterogeneous nuclear ribonucleoprotein A1

It is well known that microRNAs (miRs) are abnormally expressed in various cancers and target the messenger RNAs (mRNAs) of cancer-associated genes. While (miRs) are abnormally expressed in various cancers, whether miRs directly target oncogenic proteins is unknown. The present study investigated the inhibitory effects of miR-18a on colon cancer progression, which was considered to be mediated through its direct binding and degradation of heterogeneous nuclear ribonucleoprotein A1 (hnRNP A1). An MTT assay and xenograft model demonstrated that the transfection of miR-18a induced apoptosis in SW620 cells. A binding assay revealed direct binding between miR-18a and hnRNP A1 in the cytoplasm of SW620 cells, which inhibited the oncogenic functions of hnRNP A1. A competitor RNA, which included the complementary sequence of the region of the miR-18a-hnRNP A1 binding site, repressed the effects of miR-18a on the induction of cancer cell apoptosis. In vitro single and in vivo double isotope assays demonstrated that miR-18a induced the degradation of hnRNP A1. An immunocytochemical study of hnRNP A1 and LC3-II and the inhibition of autophagy by 3-methyladenine and ATG7, p62 and BAG3 siRNA showed that miR-18a and hnRNP A1 formed a complex that was degraded through the autophagolysosomal pathway. This is the first report showing a novel function of a miR in the autophagolysosomal degradation of an oncogenic protein resulting from the creation of a complex consisting of the miR and a RNA-binding protein, which suppressed cancer progression.

Homoeologous chromosomes of Xenopus laevis are highly conserved after whole-genome duplication

It has been suggested that whole-genome duplication (WGD) occurred twice during the evolutionary process of vertebrates around 450 and 500 million years ago, which contributed to an increase in the genomic and phenotypic complexities of vertebrates. However, little is still known about the evolutionary process of homoeologous chromosomes after WGD because many duplicate genes have been lost. Therefore, Xenopus laevis (2n=36) and Xenopus (Silurana) tropicalis (2n=20) are good animal models for studying the process of genomic and chromosomal reorganization after WGD because X. laevis is an allotetraploid species that resulted from WGD after the interspecific hybridization of diploid species closely related to X. tropicalis. We constructed a comparative cytogenetic map of X. laevis using 60 complimentary DNA clones that covered the entire chromosomal regions of 10 pairs of X. tropicalis chromosomes. We consequently identified all nine homoeologous chromosome groups of X. laevis. Hybridization signals on two pairs of X. laevis homoeologous chromosomes were detected for 50 of 60 (83%) genes, and the genetic linkage is highly conserved between X. tropicalis and X. laevis chromosomes except for one fusion and one inversion and also between X. laevis homoeologous chromosomes except for two inversions. These results indicate that the loss of duplicated genes and inter- and/or intrachromosomal rearrangements occurred much less frequently in this lineage, suggesting that these events were not essential for diploidization of the allotetraploid genome in X. laevis after WGD.

Mast cell maturation is driven via a group III phospholipase A2-prostaglandin D2-DP1 receptor paracrine axis

Microenvironment-based alterations in phenotypes of mast cells influence the susceptibility to anaphylaxis, yet the mechanisms underlying proper maturation of mast cells toward an anaphylaxis-sensitive phenotype are incompletely understood. Here we report that PLA2G3, a mammalian homolog of anaphylactic bee venom phospholipase A2, regulates this process. PLA2G3 secreted from mast cells is coupled with fibroblastic lipocalin-type PGD2 synthase (L-PGDS) to provide PGD2, which facilitates mast-cell maturation via PGD2 receptor DP1. Mice lacking PLA2G3, L-PGDS or DP1, mast cell-deficient mice reconstituted with PLA2G3-null or DP1-null mast cells, or mast cells cultured with L-PGDS-ablated fibroblasts exhibited impaired maturation and anaphylaxis of mast cells. Thus, we describe a lipid-driven PLA2G3-L-PGDS-DP1 loop that drives mast cell maturation.

Global metabolomic analysis of heart tissue in a hamster model for dilated cardiomyopathy

Dilated cardiomyopathy (DCM), a common cause of heart failure, is characterized by cardiac dilation and reduced left ventricular ejection fraction, but the underlying mechanisms remain unclear. To investigate the mechanistic basis, we performed global metabolomic analysis of myocardial tissues from the left ventricles of J2N-k cardiomyopathic hamsters. This model exhibits symptoms similar to those of human DCM, owing to the deletion of the δ-sarcoglycan gene. Charged and lipid metabolites were measured by capillary electrophoresis mass spectrometry (MS) and liquid chromatography MS(/MS), respectively, and J2N-k hamsters were compared with J2N-n healthy controls at 4 (presymptomatic phase) and 16weeks (symptomatic) of age. Disturbances in membrane phospholipid homeostasis were initiated during the presymptomatic phase. Significantly different levels of charged metabolites, occurring mainly in the symptomatic phase, were mapped to primary metabolic pathways. Reduced levels of metabolites in glycolysis, the pentose phosphate pathway, and the tricarboxylic acid cycle, together with large decreases in major triacylglycerol levels, suggested that decreased energy production leads to cardiac contractile dysfunction in the symptomatic phase. A mild reduction in glutathione and a compensatory increase in ophthalmate levels suggest increased oxidative stress in diseased tissues, which was confirmed by histochemical staining. Increased levels of 4 eicosanoids, including prostaglandin (PG) E2 and 6-keto-PGF1α, in the symptomatic phase suggested activation of the protective response pathways. These results provide mechanistic insights into DCM pathogenesis and may help identify new targets for therapeutic intervention and diagnosis.

Abstract P3-10-09: Peptide-based molecular targeting of inflammatory breast cancer

Inflammatory breast cancer (IBC) is a subtype of breast cancer that has a frequent association with metastatic disease and a poorer prognosis than comparative non-inflammatory breast cancers. While IBC is now considered a distinct subclass of breast cancer, the lack of molecular characterization, both at the genomic and proteomic levels, has hampered the development of rationalized and targeted therapies. Inherent receptor/ligand interactions that can occur on the surface of tumor cells can act as a dynamic molecular address that can enable targeted delivery of drugs and imaging agents to tumors. We hypothesize that such molecular addresses within IBC can be exploited for ligand-based imaging and early detection of disease sites. To this end, it is our goal to generate targeted imaging and therapeutic agents by combining ligand-directed targeting with efficient transduction of IBC cells by hybrid gene delivery vectors. Our strategy utilizes a hybrid vector with genomic elements from adeno-associated virus (AAV) and an M13-derived phage. Ligand-targeted, AAV/phage (AAVP) chimeras can display tumor-homing peptides that mediate selective internalization of viral particles through specific ligand-receptor interactions in vitro and in vivo. Such targeted vehicles are suited for the delivery of different reporter genes that can be used for imaging, diagnosis and therapy of breast cancer

As a part of our ongoing studies we have identified, characterized and evaluated a peptide (WIFPWIQL, amino acid sequence) that can target GRP78, a stress-response protein that is expressed in IBC tumors and elevated during metastatic progression. Indeed, we found that this GRP78-targeting peptide can bind to, and internalize within IBC cells. As a result, we sought to characterize the ability of this peptide to mediate the delivery of fluorescent-based compounds and toxic moieties in preclinical models of IBC and breast cancer metastasis. Using amine-based chemical coupling, we conjugated near-infrared dyes on both WIFPWIQL-phage and on a WIFPWIQL-peptide engrafted antibody. When these fluorescent construct were administered into mice bearing IBC or IBC-like tumors, we could visualize tumor-specific targeting of the vectors in vivo. To demonstrate efficacy of GRP78-targeted therapeutics, we conjugated the tumor-homing, GRP78 ligand to a cell-death inducing domain (creating a compound called BMTP-78, βone metastasis targeting peptide-78), which can selectively kill cells upon internalization. We show here that BMTP78 therapy in mice with established GRP78-positive tumors, but not matched GRP78-negative tumors, could effectively reduce tumor growth and metastatic burden. Finally, we demonstrate a WIFPWIQL-AAVP construct that expresses a suicide gene (HSVtk) under the control of either CMV or GRP78 promoter, could sensitize IBC tumor xenografts to the pro-drug ganciclovir. Collectively, our results demonstrate an in vivo receptor/ligand system that has the potential for imaging and therapeutic targeting of IBC and aggressive breast tumors.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P3-10-09.

Growth suppression of low HER-2/neu-expressing breast cancer cell line MDA-MB-435 by tyrosine kinase inhibitor emodin

The tyrosine kinase inhibitor emodin (3-methyl-1,6,8-tridroxyanthaquinone) is known to preferentially suppress the growth of the HER-2/neu-overexpressing breast cancer cell line. In this study, emodin effectively suppressed growth of MDA-MB-435, a breast cancer cell line with low HER-2/neu expression. Since emodin is a tyrosine kinase inhibitor, we questioned whether another tyrosine kinase might play a role in the tumorigenicity of MDA-MB-435. By Western blotting with anti-phosphotyrosine antibody, we detected a 72-kDa protein which is uniquely phosphorylated on tyrosine in MDA-MB-435. The level of phosphotyrosine in the 72-kDa protein was significantly reduced by treatment with emodin. This suggests that a strong tyrosine kinase may reside in MDA-MB-435 and the 72-kDa protein serves as a substrate for the tyrosine kinase.

Stenotrophomonas maltophilia infection in hematopoietic SCT recipients: high mortality due to pulmonary hemorrhage

To clarify the clinical features and outcome of Stenotrophomonas maltophilia infection among hematopoietic SCT (HCT) recipients, we retrospectively reviewed the records of 1085 consecutive HCT recipients and identified 42 episodes in 31 HCT recipients with S. maltophilia infection. We compared these recipients with 30 non-HCT patients with S. maltophilia infection. The mortality rate in HCT recipients was significantly higher than that in non-HCT patients (relative risk 5.7, P=0.04), and we identified seven patients with pulmonary hemorrhage due to S. maltophilia, exclusively in the HCT cohort. Six of these latter seven patients died within 1 day from the onset of hemorrhage and the isolate was identified after death in most cases; one patient, who received empiric therapy for S. maltophilia and granulocyte transfusion, survived for more than 2 weeks. The patients with pulmonary hemorrhage had a more severe and longer duration of neutropenia, persistent fever despite of the use of broad-spectrum antibiotics, complication by pneumonia and higher C-reactive protein levels than those without pulmonary hemorrhage. In conclusion, S. maltophilia was associated with fulminant and fatal pulmonary hemorrhage in HCT recipients. Empiric therapy with antibiotics before the onset of pulmonary hemorrhage may be effective in HCT recipients who carry the conditions identified.

P4-20-05: Inflammatory Breast Cancer: Comparison of Epidemiology, Biology, and Prognosis between Japan and the United States, a Hospital-Based Study

Background: Inflammatory breast cancer (IBC) is a challenging disease characterized by low incidence, rapid progression, and poor survival. The epidemiology of IBC has been slow to emerge, given that the rarity of IBC makes large prospective clinical trials difficult. Compared to non-IBC, well-established features of IBC include a younger age of onset and lower frequency of hormone receptor positivity. Higher body mass index (BMI) is a purported risk factor. Previous reports also suggest that IBC is associated with more racial disparities, including incidence and age at diagnosis. The epidemiology of IBC in East Asia, however, has not been investigated. We performed a comparative study of IBC in Japan versus the United States to determine its epidemiologic and clinical features and to evaluate the differences in epidemiological factors between the two countries.

Patients and Method: Patients who visited St. Luke's International hospital (SLIH) in Tokyo, Japan and The University of Texas MD Anderson Cancer Center (MDA) in Texas, USA between 2003 and 2009 were identified. Epidemiological and biological data were collected from electronic medical records. Patient and tumor characteristics were tabulated and stratified by hospital. Kaplan-Meier curves were created for survival estimates and log-rank test was used for cross-group comparisons. Cox proportional-hazard analysis was used to identify a subset of significant prognostic variables that related to overall survival.

Result: 34 patients at SLIH and 531 patients at MDA were identified. Mean age at diagnosis was 52 years old (range, 32–81, SD, 10.8) and 50 years old (range, 22–87, SD, 11.6), respectively (P=0.476). Mean BMI was 22.9 kg/m2 (range, 17.3−30.5, SD 3.3 ) and 31.0 kg/m2 (range, 13.6−88.9, SD, 7.8) respectively (P<0.01). Clinical Staging was not significantly different; Stage IIIB 38.2%, Stage IIIC 26.5%, and Stage IV 32.4% at SLIH versus 48.6%, 23.7%, and 27.3% at MDA (P= 0.167). Estrogen receptor (ER) and progesterone receptor (PR) negative cases were, respectively, 50.0% and 64.7% at SLIH and 50.5% and 64.2% at MDA (ER, P= 0.935; PR, P=0.908). Her-2 over-expression cases were 38.2% at SLIH and 28.6% at MDA (P=0.174). A significant difference in nuclear grade was seen between SLIH and MDA: 20.6% at SLIH were Grade 3 versus 68.7% at MDA (P<0.01). Median overall survival at SLIH was 3.6 years versus 2.3 years at MDA (P=0.570). No prognostic factors were associated with overall survival.

Conclusion: Though IBC at SLIH differed significantly from IBC at MDA by several epidemiologic and biologic factors, there was no significant difference in survival. To define the epidemiological, prognostic, and risk factors of IBC in Japan, as well as in the world, further studies are needed.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-20-05.

P2-01-13: Impact of Erlotinib on MSC-Mediated TIC Expansion and EMT

Background: Recently, we have demonstrated that mesenchymal stem cells (MSC) and MSC secreted factors (MSC-CM) have a profound effect on tumor initiating cells (TIC) enriched mammosphere formation and latency of tumor xenografts formation from breast cancer cell lines. Furthermore these interactions increased the expression of epithelial mesenchymal transition (EMT)-associated proteins which are associated with tumor cell invasion and metastasis as well as the TIC phenotype. (Klopp, A. H. et al., 2010, PLoS One. 5, e12180). Our data suggest that the presence of MSC in the tumor microenvironment may increase metastases by conferring stem progenitor cell biology on more differentiated non-metastatic cells. In addition, preliminary data suggested MSC-CM upregulated EGFR signaling in breast cancer cells. Therefore, we hypothesized that inhibiting EGFR signaling with erlotinib (tyrosin kinase inhibitor) can suppress MSC-mediated TIC expansion and EMT.

Methods & Results: In order to demonstrate that erlotinib inhibits MSC-CM promoted expansion of TIC, we cultured breast cancer cells lines (SUM149, SUM159, SUM190, MDA-IBC3 and MCF-7) in anchorage independent conditions with MSC-CM and treated them with increasing concentrations of erlotinib. The efficiency of mammosphere formation was examined after 5 days. We found that erlotinib inhibited MSC mediated increase in mammosphere formation in triple negative cell lines SUM149 and SUM159, and HER2−positive cell lines SUM190 and MDA-IBC3, but not in ER-positive, erlotinib resistant MCF-7 cells. Furthermore, we evaluated the impact of erlotinib on cell cultures grown with breast cancer patient-derived fluids, such as seroma and malignant pleural effusions. We observed that the effect of erlotinib on mammospheres formation was attenuated by both types of patient fluids.

Discussion: Patients with triple negative breast cancer have the highest rates of metastases and no available targeted therapies for treatment. EGFR is expressed in a significant proportion of triple negative breast cancers, and recent clinical and preclinical studies suggest that EGFR may contribute to the metastasis or aggressiveness of triple negative breast cancer. Here we demonstrate that host and environmentally-derived factors are critical for determining resistance to erlotinib. In vivo studies regarding the ability of erlotininb to prevent MSC-enhanced TIC survival and metastases are underway.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-01-13.

P1-04-01: The Mechanism of Anti-Breast Cancer TICs Effect of Pyrvinium Pamoate Is through WNT/beta-Catenin Signaling

We have previously shown that pyrvinium pamoate can decrease breast cancer TICs in vitro and shrink the tumor size in vivo. Although pyrvinium pamoate has been shown to target beta-catenin through activating CK-1alpha in a vitro model, the mechanism of its anti-breast cancer TICs effect is unknown. Herein, we use a constitutively active WNT/beta-catenin signaling construct EBETAP (ref) to determine if the anti-breast TIC effect of pyrvinium pamoate is through WNT/beta-catenin signaling. Using aldefluor expression and mammosphere formation efficiency as TIC surrogate assays, we found that TICs of SUM-159 transfected with EBETAP construct are resistant to pyrvinium pamoate treatment compared to control cells. Moreover, microarray analysis reveals a series of genes and signaling downstream of WNT-catenin were down-regulated in SUM-159 cells treated with pyrvinium pamoate. In summary, mechanism of anti-breast cancer TICs effect of pyrvinium pamoate is through WNT/beta-catenin signaling.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-04-01.

P5-01-17: HER2 Amplification in Primary Tumor: A Potential Marker for Presence of Circulating Tumor Cells in Inflammatory Breast Cancer Patients?

Background: Inflammatory breast cancer (IBC) is a rare but aggressive form of invasive breast cancer accounting for 3–6% of all cases and have higher rates of distant recurrence. Circulating tumor cells (CTCs) are known to predict outcome in metastatic breast cancer (BC) patients, but little is known about their prognostic significance in non-metastatic BC. We hypothesized that CTCs can be identified in patients with IBCs and may correlate with primary tumor characteristics. Methods: All patients had blood samples collected at the time of primary surgery. CTCs (per 7.5 ml blood) were detected using the Cell Search™ system (Veridex) and were defined as nucleated cells lacking CD45 but expressing cytokeratins (CK) 8, 18, or 19. The presence of ≥ 1 epithelial cells meeting morphologic criteria for malignancy was considered a positive result. Statistical analyses employed Chi square and Fisher's exact tests using STATA IC 11. Results: We prospectively evaluated 41 IBC patients enrolled in an IRB approved protocol undergoing surgery for stage I-III breast cancer. Median follow-up was 30 months. Mean age was 52 years. Thirty five patients (94%) had positive lymph nodes (LNs) at presentation, 30 (75%) had high-grade tumors and 20 (53%) had lymphovascular invasion. Eleven patients (28%) were ER positive, 11 (27%) were PR positive and 18 (44%) were HER2 positive. IBCs were more likely to be high grade (P<0.0001), ER negative (P<0.0001), PR negative (P<0.0001), HER2 positive (P<0.0001), High Ki-67 (P= 0.005) and had a BMI of more than 25kg/m2 (P=0.04). Eleven (27%) patients were CTC positive. CTCs were more likely be found in HER2 positive (8/18; 44%) vs. HER2 negative primary tumors (3/20; 15%) [OR= 4.53; 95% C.I. = 1.02−19.52; P= 0.04]. We found no statistically significant correlations between primary tumor characteristics (ER, PR, LNs, high grade) and presence of CTCs. Conclusions: About a quarter of IBC patients had CTCs at the time of primary surgery. In these patients HER2 overexpression predicted the presence of CTCs. Studies with longer follow-ups is needed to determine if CTCs predicted survival.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P5-01-17.

The diagnostic accuracy of high-resolution endoscopy, autofluorescence imaging and narrow-band imaging for differentially diagnosing colon adenoma

BACKGROUND AND STUDY AIMS

Conventional colonoscopy can result in unnecessary biopsy or endoscopic resection due to its inability to distinguish adenomas from hyperplastic polyps. This study therefore evaluated the efficacy of high-resolution endoscopy (HRE), autofluorescence imaging (AFI), and narrow-band imaging (NBI) in discriminating colon adenoma from hyperplastic polyps.

PATIENTS AND METHODS

This was a prospective multicenter study in patients undergoing AFI and NBI examinations. HRE, AFI, and NBI images were classified into two groups based on morphological characteristics, the predominant color intensities, and the visibility of meshed capillary vessels, respectively. Each of the endoscopic photographs were independently evaluated by a single endoscopist. The images were then assessed by three specialists and three residents, the latter having performed < 500 colonoscopies and < 30 NBI and AFI examinations. Diagnostic test statistics were calculated to compare the accuracy in differentiating colon adenoma from hyperplastic polyps for each method.

RESULTS

A total of 183 patients were enrolled in the study and 339 adenomas and 85 hyperplastic polyps were identified. AFI and NBI could distinguish adenoma from hyperplastic polyps with an accuracy of 84.9 % and 88.4 %, respectively, whereas HRE exhibited an accuracy of 75.9 %. In the 358 lesions in which the AFI diagnosis was consistent with that of NBI, the accuracy, sensitivity, and specificity were high, at 91.9 %, 92.7 %, and 92.9 %, respectively. During the study comparing specialists and residents, AFI and NBI dramatically improved the diagnostic accuracy of residents from 69.1 % to 86.1 % and 84.7 %, respectively.

CONCLUSIONS

Both AFI and NBI are considered to be feasible tools that can discriminate colon adenoma from hyperplastic polyps, and their use may be particularly beneficial for less-experienced endoscopists.

Analysis of two major intracellular phospholipases A(2) (PLA(2)) in mast cells reveals crucial contribution of cytosolic PLA(2)α, not Ca(2+)-independent PLA(2)β, to lipid mobilization in proximal mast cells and distal fibroblasts

Mast cells release a variety of mediators, including arachidonic acid (AA) metabolites, to regulate allergy, inflammation, and host defense, and their differentiation and maturation within extravascular microenvironments depend on the stromal cytokine stem cell factor. Mouse mast cells express two major intracellular phospholipases A(2) (PLA(2)s), namely group IVA cytosolic PLA(2) (cPLA(2)α) and group VIA Ca(2+)-independent PLA(2) (iPLA(2)β), and the role of cPLA(2)α in eicosanoid synthesis by mast cells has been well documented. Lipidomic analyses of mouse bone marrow-derived mast cells (BMMCs) lacking cPLA(2)α (Pla2g4a(-/-)) or iPLA(2)β (Pla2g6(-/-)) revealed that phospholipids with AA were selectively hydrolyzed by cPLA(2)α, not by iPLA(2)β, during FcεRI-mediated activation and even during fibroblast-dependent maturation. Neither FcεRI-dependent effector functions nor maturation-driven phospholipid remodeling was impaired in Pla2g6(-/-) BMMCs. Although BMMCs did not produce prostaglandin E(2) (PGE(2)), the AA released by cPLA(2)α from BMMCs during maturation was converted to PGE(2) by microsomal PGE synthase-1 (mPGES-1) in cocultured fibroblasts, and accordingly, Pla2g4a(-/-) BMMCs promoted microenvironmental PGE(2) synthesis less efficiently than wild-type BMMCs both in vitro and in vivo. Mice deficient in mPGES-1 (Ptges(-/-)) had an augmented local anaphylactic response. These results suggest that cPLA(2)α in mast cells is functionally coupled, through the AA transfer mechanism, with stromal mPGES-1 to provide anti-anaphylactic PGE(2). Although iPLA(2)β is partially responsible for PGE(2) production by macrophages and dendritic cells, it is dispensable for mast cell maturation and function.

Abstract P6-14-06: Prospective Testing of Three Different Gene-Signatures for Patient Selection for Dasatinib Therapy in Metastatic Breast Cancer

Background: Several gene signature-based predictors of response to targeted drugs have been proposed in the literature but none has been prospectively tested as patient selection tools in the clinic. The goal of this trial is to assess the positive predictive value of 3 conceptually different multi-gene signatures as predictors of response to the multitargeted kinase inhibitor dasatinib.

Methods: This clinical trial requires biopsy of a metastatic lesion for gene expression profiling and employs a parallel, multi-arm, two-step, phase II design. Three markers are assessed including a (i) cell-line derived dasatinib-sensitivity signature, (ii) a src-pathway activity signature and (iii) a dasatinib target index calculated as the weighted average expression of all known dasatinib targets. Only markerpositive patients are treated with dasatinib 100 mg po daily and each marker arm is considered as a separate study with early stopping rules for futility (minimum sample size 9, maximum sample size 40/marker arm). A predictor is considered worthy of further study if the clinical benefit rate (i.e. positive predictive value) is ≥25%.

Results: Forty seven patients were accrued from July 2009 through June, 2010, 49 biopsies were performed (soft tissues n=31, liver n=8, bone n=3, lung n=1, adrenal gland n=1), 6 samples had poor cellularity and 3 failed array QC. There was no patient recall, hospitalization or emergency room visit due to biopsy procedure. The median time from biopsy to genomic prediction result was 5 days (range 3-7). Twenty three (57%) patients had positive result for at least 1 predictor (5 were positive for 2) and 20 are receiving therapy (3 withdraw or progressed before therapy began). Responses as of June 2010; Target index arm (n=9): 5 PD (progressive disease), 4 SD (3 stable disease at 8 weeks 1 SD at 16 weeks); SRC Pathway arm (n=5): 3 PD, 2 SD at 8 weeks; Cell line predictor arm (n=6): 2 PD, 1 SD at 8 weeks, 3 not yet reached response evaluation. None of the 3 predictive marker arms have met early stopping yet and accrual is ongoing. Conclusion: Gene-expression signature based patient selection for targeted therapy is feasible and FNA biopsies of metastatic lesions for genomic testing are safe. Updated efficacy results will be reported.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P6-14-06.

p53 Mutation in Inflammatory Breast Cancer Cell Lines

Background: Inflammatory breast cancer (IBC) is the most aggressive manifestation of primary breast cancer and represents 1% to 2% of primary breast cancer in the United States. IBC is characterized by an acute inflammation of the skin of the affected breast generally believed to be caused by blockage of the dermal lymphatics by tumor emboli. Wild type (WT) p53 is a tumor suppressor gene, which induces apoptosis and p53 mutations are associated with poor prognosis in breast cancer. Compared with locally advanced breast cancers, IBC patients have higher levels of mutated p53 protein that has been associated with more aggressive tumors, anthracycline resistance, shorter progression free survival, shorter overall survival, and less favorable long-term outcome. The aim of this study was to determine if there are unique genetic variations in IBC cell lines that would provide specific genetic p53 mutations that could be exploited for targeted therapy with the intent of improving response to treatment and overall survival in IBC.Materials and Methods: Genomic DNA was extracted from six breast cancer cell lines (MDA-453, SUM149, MCF-7, KPL4, MDA321, and SUM190) and the immortalized human mammary epithelial cells (HMLE) using the Qiagen DNA Blood Mini Kit (Valencia, CA). Among the 6 breast cancer cell lines, KPL-4, SUM149 and SUM190 are IBC cell lines; MDA231 and SUM149 have basal-like phenotype; MCF-7 has wild-type p53; SUM190 and KPL-4 are Her2 amplified. The DNA purity and concentration were determined by spectrophotometric measurements of absorbance at 260nm and 280 nm. Polymerase chainreaction (PCR) was performed to amplify the fragments of exons 2-11 of the p53gene using consensus primers. The PCR products were scanned and identified using the Agilent Bioanalyzer 2100. DNA sequencing was performed on PCR products in the ABI PRISM 310 Genetic Analyzer. The BLAST search was used to identify p53 mutations compared with the reference sequence, X54156, from Genbank.Results: We screened 2-11 exon sequences of the p53 gene in the 7 human breast cell lines. We identified two IBC cell lines (SUM149, SUM-190) with a p53 gene alteration that predicted a change in the encoded protein, SUM149 at exon 7 (ATG to ATA, Met-237-Ile) and SUM190 at exon 9 (CAG to TAG, Gln -317-stop). Both mutations have been previously reported. Five nonsense mutations were identified in two other cell lines, MDA-453 and MDA321. No mutations were identified in KPL4 and HMLE cells.Conclusions: The p53 mutation profile in breast cancer cell lines suggests an additional biological feature for the characterization of IBC. Furthermore, these data support the previously reported association between p53 status and chemo- and radioresistance in this disease responsible for poor prognosis. Therapies directed to restore p53 function should be explored in IBC models and in clinical trials.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3161.

Circulating Tumor Cells and FDG-PET/CT for the Therapeutic Monitoring of Bone Metastases from Breast Cancer

Background: Circulating tumor cells (CTCs) and [18F]fluorodeoxyglucose positron emission tomography/computed tomography (FDG-PET/CT) are two promising new tools for monitoring therapy in patients with metastatic breast cancer. The two modalities showed high sensitivity in detection of bone relapse/progression from breast cancer (De Giorgi U et al. Ann Oncol 2009). In this study, we sought to evaluate the prognostic significance of two different modalities represented by the detection of CTC and FDG-PET/CT in patients with bone metastases from breast cancer treated with standard therapies. Our objective was to compare the two modalities to identify which technology could be more sensitive in prospectively monitoring such patients.Patients and Methods: This is a retrospective study of 54 patients with bone metastases from breast cancer without visceral metastases treated at The University of Texas M. D. Anderson Cancer Center from September 2004 to May 2008. CTC were detected and enumerated using the CellSearch system (Veridex LLC, Rariten NJ, USA). Patients were categorized according to first follow-up CTC counts as having a favorable (&lt; 5 CTC/7.5 mL of blood) or unfavorable (≥ 5 CTC) outcome. Reassessment of disease status by CTC count and FDG-PET/CT was performed approximately 2-3 months after initiation of the new treatment, depending on treatment type and schedule. Progression-free survival (PFS) and overall survival (OS) were estimated by Kaplan-Meier product limit method, and compared between groups with the log-rank test.Results: In 54 evaluable patients, the median overall survival time was 17 months (range, 3 to &gt;36). Follow-up CTC levels and FDG-PET/CT response predicted both PFS (p = 0.02 and p = 0.0001, respectively) and OS (p = 0.01 and p = 0.02, respectively), while baseline CTC predicted neither PFS (p = 0.8) nor OS (p = 0.76). In patients with either CTC or FDG-PET/CT response PFS has been 13 months, while in patients with discordant CTC and FDG-PET/CT response PFS has been 6 months and in patients with neither CTC nor FDG-PET/CT response PFS has been 5 months (p = &lt;0.00002). In patients with either CTC or FDG-PET/CT response, OS has not been reached (&gt;31 months); in patients with discordant CTC and FDG-PET/CT response, OS has been 24 months; and in patients with neither CTC nor FDG-PET/CT response, OS has been 18 months (p = 0.02).Conclusions: CTC and FDG-PET/CT are useful tools for therapeutic monitoring of bone metastases from breast cancer. Prospective studies in this specific clinical context are needed to assess the critical roles that CTC and FDG-PET/CT individually as well as collectively play in the prognostic and therapeutic monitoring of bone metastases from breast cancer.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 1109.

Addition of Granulocyte-Macrophage Colony-Stimulating Factor (GM-CSF) to Trastuzumab Stabilizes Disease in Patients with Trastuzumab-Resistant, HER2+ Metastatic Breast Cancer

Introduction: Trastuzumab with or without chemotherapy is the standard of care for patients with HER2+ metastatic breast cancer. The proposed mechanism of trastuzumab-induced regression of HER2+ tumors includes inhibition of tumor cell proliferation, potentiation of chemotherapy, and facilitation of immune function through antibody-dependent cell-mediated cytotoxicity. GM-CSF (Leukine) is a cytokine that mediates antibody-dependent cell-mediated cytotoxicity. We studied the feasibility and efficacy of adding GM-CSF to trastuzumab in patients with trastuzumab-resistant, HER2+ metastatic breast cancer.Patients and Methods: Patients with measurable, HER2+ metastatic breast cancer that progressed after treatment with trastuzumab with or without chemotherapy were continued on trastuzumab alone at 2 mg/kg intravenous weekly. GM-CSF (250 μg/m2 subcutaneous daily) was added until the absolute neutrophil count (ANC) was greater than 10,000/mm3, then given every other day while the ANC was maintained below 10,000/mm3. Disease was restaged every 8 weeks. Treatment with trastuzumab and GM-CSF was continued until disease progression or intolerable toxicity.Results: Of 18 eligible patients with progressive HER2+ metastatic breast cancer, 17 (median age 48 yr, range 27–75 yr) were evaluable. Nine had hormone receptor–positive disease. The median number of metastatic sites was 2 (range 1–3); the most common site was the liver (n=10). The median number of prior regimens (trastuzumab with or without chemotherapy) for metastatic disease was 2 (range 1–5). One patient developed rapidly progressive disease 2 weeks after the start of study therapy and died soon after. The other 16 patients continued treatment until disease progression. No disease response was observed, but 5 patients (29%) had stable disease with a median duration of 15.8 weeks (range 10–53.9 weeks). Thirteen patients had grade 1 toxic effects; 6 patients, grade 2; and 2 patients, grade 3 (fatigue and muscle aches). The most common toxic effect was rash at the injection site, followed by skin rash, fatigue, and muscle aches. No grade 4 or irreversible toxic effect was seen.Conclusion: The addition of GM-CSF to trastuzumab alone in patients with trastuzumab-resistant, HER2+ metastatic breast cancer stabilizes the disease for a median duration of 15.8 weeks without causing any significant toxic effects in 29% of heavily pretreated patients. Its administration is simple, safe, and feasible. This regimen, trastuzumab and GM-CSF, needs further evaluation in combination with chemotherapy or other biological agents.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 5103.

Effect of Trastuzumab and Chemotherapy on Circulating Tumor Cells in Patients with Poor Prognosis Metastatic Breast Cancer

Background. Trastuzumab has significant activity in HER2 neu amplified metastatic breast cancer (MBC). We hypothesized that it may selectively act against circulating tumor cells (CTC) in HER2-positiveMBC. We assessed the effect of trastuzumab-based regimens on CTC in HER2-positive MBC with poor prognosis (≥ 5 CTC).Patients and Methods. We retrospectively evaluated patients with poor prognosis MBC (baseline ≥ 5 CTC) treated with a first-line regimen consisting of trastuzumab+antimitotic agents in 11 HER2-positive patients not previously pretreated with trastuzumab, chemotherapy with antimitotic agents in 24 HER2-normal patients, and other chemotherapeutic drugs (mainly capecitabine) in other 16 HER2-normal patients. CTC were detected and enumerated using the CellSearch system (Veridex LLC, Warren NJ, USA). We evaluated the effect on CTC counts and on progression-free survival (PFS) and overall survival (OS).Results. At a median follow-up of 16 months (range, 4 to 48), 24 patients (47%) died. All 11 HER2-positive patients treated with trastuzumab+antimitotic agents had &lt;5 CTC during the treatment. Only 16 (67%) with HER2-normal MBC had &lt;5 CTC with antimitotic agents (p = 0.037), and 28 (70%) with other chemotherapeutic regimens (p = 0.048). No statistically significant difference was observed between patients treated with antimitotic agents and those treated with other chemotherapeutic agents (p = 0.73). There was no difference between patients receiving polychemotherapy and monochemotherapy (p = 0.73). The median PFS was 12 months in HER2-positive patients treated with trastuzumab+antimitotic agents compared with 7 months for those with HER2-normal (p = 0.09). The median OS was not reached (&gt;20 months) and 19 months (p = 0.034), respectively. The median PFS was 8 months in HER2-normal patients with ≥5 CTC and 4 months in those with &lt;5 CTC (p = 0.01). The median OS was not reached (&gt;17 months) and 9 months (p = 0.01), respectively.Conclusions. Trastuzumab is highly effective in patients with HER2-positive MBC with poor prognosis (≥ 5 CTC). Antimitotic agents and other chemotherapy agents did not show a similar effect in HER2-normal MBC. CTC might be useful in the monitoring of poor prognosis MBC patients undergoing therapy with trastuzumab.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3014.

Synergistic Effect of Lapatinib and the Class 1 HDAC Inhibitor SNDX-275 in Breast Cancer

Background: Inflammatory breast cancer (IBC) is a rare but aggressive form of primary breast cancer with high metastasis rates and poor survival outcomes in patients. Currently, no specific targeted therapy is available to improve patient outcomes, although agents (i.e. trastuzumab and lapatinib) targeting the human epidermal growth factor 2 (HER2) have shown promise in clinical trials. Histone deactylases (HDACs) represent another family of proteins for which inhibitors have been clinically validated and shown to inhibit proliferation of breast cancer cells in vitro and in vivo. In these studies we determined the single agent activity of the class 1 selective HDAC inhibitor entinostat (SNDX-275) in IBC cell models and whether SNDX-275 was synergistic with the HER2 targeted agent lapatinib.Methods: SNDX-275 activity was evaluated in SUM190, SUM149 and KPL-4 IBC cell lines using standard proliferation assays and compared to the non-IBC cell lines MDA-MB-231, SKBr3 and MCF-7. Apoptotic activity and cell cycle analysis were analyzed. SNDX-275 combination with lapatinib was initially determined in vivo in a HER2+ breast cancer model and subsequently in the SUM190, SUM149, KPL-4 IBC cells. For xenograft studies, athymic nude mice bearing human breast (BT474) tumor xenografts were treated with SNDX-275 at 15 or 30 mg/kg/day and lapatinib at 30 mg/kg/ 2xday or 75 mg/kg/ 2xday.Results: Significant anti-proliferative activity of SNDX-275 was observed in IBC (IC50, 250–500 nM) when compared with the non-IBC breast cancer cell lines MDA-MB-231, SKBr3, and MCF-7 (IC50 2–5 mM). Cell cycle analysis showed the onset of apoptosis in IBC cell lines (10%-17%); in the non-IBC cell lines, very little apoptosis occurred (0.8%–3.1%), although G1 stage arrest was seen in the non-IBC cell lines MDA-231 and MCF-7. The SNDX-275–induced apoptosis in IBC cell lines was dependent on caspase 9 rather than Caspase 8 cleavage indicating that the intrinsic apoptotic pathway is activated. The experiments with lapatinib demonstrated a significant benefit of the SNDX-275/lapatinib combination in both the BT474 xenograft study as well as the IBC cell lines tested. In the animal group that was treated with 15 mg/kg SNDX-275 plus 75 mg/kg lapatinib, synergistic effects were observed with tumor regression that was continued at least for 4 weeks after treatment was stopped. Similarly, synergistic anti-proliferative activity was found in almost all (4 of the 5) cell lines tested (SUM190, SUM149, KPL-4, and BT474). Investigation into the mechanism of SNDX-275–mediated apoptosis and the combined effects of lapatinib and SNDX-275 in IBC are under way. Our data demonstrate that HDACi as single agents and particularly in combination with HER2 targeted agents represent a promising new approach for clinical development in IBC breast cancer and patients with HER2-overexpressing breast cancer.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3135.

Clinical Outcomes in Two Different Cohorts of Patients with Inflammatory Breast Cancer (IBC) Treated at the MD Anderson Cancer Center: The Experience of the Morgan Welch IBC Research Program and Clinic

BACKGROUND: Inflammatory Breast Cancer (IBC) is a rare but aggressive manifestation of primary breast cancer. Survival in patients with IBC is significantly lower than for non-IBC breast cancer patients. Appropriate diagnostic and treatment strategies provided by a specialized multidisciplinary team could impact the overall prognosis of the disease. We recently established an IBC research program and clinic including investigators from various disciplines solely dedicated to this disease. We sought to compare the characteristics and clinical outcomes of newly diagnosed IBC patients evaluated and treated using novel diagnostic and therapeutic approaches with an historical cohort of IBC patients treated at our institution.METHODS: We included 240 IBC patients treated at MD Anderson Cancer Center between January 1970 and August 2000. In this analysis we compared characteristics, 1 year progression free survival (PFS) and 1 year survival between the historic cohort and 47 patients diagnosed with IBC and seen at our IBC clinic between August 2007 and September 2008. The new patients are part of a prospective IBC registry. All of them had staging and monitoring with breast MRI and FDG-PET/CT. When indicated, they were treated with targeted therapies (e.g. trastuzumab and tipifarnib), that were not available for the patients in the old cohort. Descriptive statistics were used. Kaplan Meier product-limit method was used to calculate survival outcomes, groups were compare by log-rank test.RESULTS: Median age was similar in both cohorts (53 vs 51). In the new cohort 40% of the patients had evidence of distant metastasis at presentation. The most common sites were contralateral lymph nodes (26%), pleura (16%), bone (16%) and liver (11%). In the old cohort only 17% presented with stage IV. 38.7% of the new patients had Her2-neu amplified and 34%, triple receptor negative IBC. There was no difference in 1-year survival between the two groups (92.4% vs. 93.8%, p=0.637). For patients with stage III disease, the 1-year survival was 95% for both groups. The 1 year-PFS was 86.4% in the new cohort compared to 77.9% (p=0.43) in the old cohort. With a median follow up of 13 months, 51%of the patients in the new cohort are disease free and 87% are still alive.CONCLUSIONS: IBC is an aggressive but rare disease with poor prognosis. We have established a specialized IBC research program and clinic that introduces novel concepts and strategies in laboratory, imaging diagnostics and targeted therapies. This approach may accelerate our understanding of the biology, develop new therapeutic strategies and finally improve the outcome of IBC. Early results of this multidisciplinary approach show a modest, but not significant difference in outcome. We hope that with additional patients and longer follow-up a significant improvement in outcomes will become apparent.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 5119.

Predictive Value of Circulating Tumor Cells (CTCs) in Metastatic Breast Cancer Patients Treated by Bevacizumab-Based Therapy

Background:Circulating tumor cells (CTC) are involved in cancer dissemination and are an independent prognostic factor in metastatic breast cancer (MBC). Antiangiogenic, bevacizumab-based chemotherapy improves response rate and progression free survival in patients with metastatic breast cancer (MBC), without impact on overall survival. Preclinical data suggest the possibility of increased metastatic potential of tumor cells pretreated by anti-angiogenic therapy (Ebos et al. Cancer Cell 2009,15: 232–9). The aim of this study was to determine the prognostic value of CTC in MBC patients treated by bevacizumab-based therapy.Patients and Methods: This retrospective study included 48 MBC treated with bevacizumab combined chemotherapy regimens and 46 patients treated with chemotherapy alone between January 2004 and December 2008 at M.D.Anderson Cancer Center. CTCs were detected and enumerated before patients started therapy using the CellSearch™ system (Veridex, LLC, NJ, USA). Progression free survival (PFS) and overall survival (OS) were calculated from the date of CTC measurement, estimated by the Kaplan-Meier product limit method, and compared between groups with the log-rank test.Results: At a median follow up of 10.1 months (range: 1-26 months), 22 patients (45.8%) had died. The estimated medians of PFS in bevacizumab-treated patients were 8.1 vs. 5.2 months (p = 0.42) in patients with baseline &lt; 5 CTCs vs. ≥ 5 CTCs. Moreover, the OS for the two subgroups were 18.3 vs. 12.4 months (p = 0.41), respectively. Twenty-three patients had CTC measurements at the time of progression. Median CTC counts at baseline and at time of disease progression were 6 (range: 0-230) and 7 (range: 0-359) respectively in the bevacizumab-treated group. The median CTC counts in the control group at same time points were 7 (range: 0-724) and 2 (range:0-999), respectively. Thirteen (56.5%) and 12 (52.2%) patients had CTC ≥ 5 at baseline and at time of disease progression in bevacizumab-treated group compared to CTC counts of 24 (52.2%) and 17 (37%) in control group treated with chemotherapy without bevacizumab. Post progression overall survival in patients with CTC &lt; 5 and CTC ≥ 5 measured at time of disease progression were 11.0 and 10.4 months (p = 0.36), in the bevacizumab treated group vs. 27 and 12.4 months (p = 0.04), in the control group respectively.Conclusion: Our data support the prognostic value of CTC measured before therapy in MBC. The detection of higher CTC counts at time of disease progression and the limited prognostic value of CTC after failure of bevacizumab-based chemotherapy although intriguing, warrants further prospective investigations. Moreover, a comparison between the differential effects of monoclonal antibodies and tyrosine kinases inhibitors on CTCs detection and monitoring will better clarify the role of specific targeted therapies on micrometastatic disease.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 3013.