Abstract P5-10-05: Novel Mechanisms of Metformin Action in TN Breast Cancer: Upregulation of miRNA 141 and 192, are Associated with a Decrease in Targets GRB2 and MSN Involved in Signaling and Motility Respectively

BACKGROUND: We have previously shown that the anti-diabetic agent, metformin, inhibits cellular proliferation, colony formation and cell signaling, with an induction of S-phase arrest and apoptosis in triple negative (TN) breast cancer cell lines in vitro, and cell outgrowth and proliferation in vivo. These changes are associated with profound shifts in phosphorylated cell signaling intermediates, including EGFR, IGF-1R, Akt, MAPK and others (Liu, et al Cell Cycle 2009). We have also shown that Stat3 activity (via phosphorylation at serine and tyrosine sites) is critical to the effects of metformin against TN cells (Deng, et al Cell Cycle 2012). In unpublished studies, we have noted that metformin significantly inhibits cellular motility in vitro. In this study we focus on mechanisms underlying the effects of metformin in TN cancer cell signaling and motility.

METHODS: TN breast cancer cell lines MDA-MB-468 and MDA-MB-231were used to study mechanisms of metformin action in vitro. Invasion chamber and motility assays were used to quantitate the effects of metformin as compared to untreated controls, with and without a variety of inhibitors at normal or supraphysiological glucose concentrations. Affymetrix chips Human Gene 1.1 and miRNA 2.0 were used to identify genes and miRNA up or down regulated by metformin treatment at 6 and 24 hr at glucose concentrations of 5, 10 or 17 mM. Appropriate primers and antibodies were used to validate these data at the transcript and protein levels respectively by qRT-PCR and western blot analyses. Lentiviral expression vectors and mimics were used to manipulate miRNA expression levels. Direct targeting of the GRB2 and MSN 3′ UTR's were performed using luciferase reporters.

RESULTS: TargetScan and Diana miR-Path analysis of miRNA's up-regulated at 6 hr following metformin treatmetns identified genes that were down regulated with metformin treatment such as GRB2 (a predicted target of miR-141) and MSN (a predicted target of miR-192), as possible mechanisms of drug action. GRB2 regulated the phosphorylation of numerous receptor tyrosine kinase (RTK) gene pathway intermediates, including those downstream of EGFR, IGF-1R and MAPK. Knock-down of miR-141 by an antagomir showed that miR-141 regulated GRB2. Invasion chamber and motility assays confirm that the metformin associated reduction in TN cell motility and invasion capacity involved miR-193 and MSN.

CONCLUSIONS: Metformin acts by diverse molecular mechanisms; some of these may be cell type specific. In TN breast cancer cells, metformin causes a rapid increase in miR-141, which targets GRB2, a gene that encodes a critical regulator upstream of many growth factors. Metformin treatment also upregulates miR-192, which represses MSN to reduce motility and invasion.

Supported by Komen Breast Cancer Foundation Grant KG100575 (SME, JKR, ZF, NSS, ADT)

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P5-10-05.

Abstract P2-05-19: Pathway-based analysis of breast cancer

Objective: Although HER2 and ER pathways are predominant pathways altered in breast cancer, it is now well accepted that many other signaling pathways are also involved in the pathogenesis of breast cancer, especially in triple negative breast cancer. The understanding of these additional pathways may assist in identifying new therapeutic approaches for breast cancer.

Methods: 13 invasive ductal carcinoma tissues and 5 benign breast tissues were analyzed for the mRNA expression level of 1243 cancer pathway-related genes using SmartChip (WaferGen, CA), a real-time PCR-base method. In addition, the levels of 154 cancer pathway-related proteins and phosphoproteins were measured using our innovative Protein Pathway Array.

Results: Out of 1,243 mRNAs, 68.7% were detected in breast cancer and 73 mRNAs were statistically significant between benign and cancer tissues. Of these mRNAs, 105 only expressed in breast cancer tissues and 33 mRNAs only expressed in normal breast tissues. Out of 154 proteins and phosphoproteins, 39% were detected in cancer tissues and 50 proteins were significantly differentiated between tumor and normal tissues. Interestingly, only 3 genes (CDK6, Vimentin and SLUG) showed decrease of both protein and mRNA. Six proteins (BCL6, CCNE1, PCNA, PDK1, SRC and XIAP) showed differentially expressed between tumor and normal tissues but no differences were observed at mRNA levels. Analyses of mRNA and protein data using Ingenuity Pathway Analysis showed more 15 pathways were altered in breast cancers and 6 of them shared between mRNAs and proteins, including p53, IL17, HGF, NGF, PTEN and PI3K/AKT.

Conclusion: There is a broad dysregulation of various pathways in breast cancer both at protein levels and mRNA levels. It is important to note that mRNA expression does not correlate with protein level, suggesting that different regulation mechanisms between proteins and mRNAs.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P2-05-19.

Abstract P5-03-14: Expression of ALDH1 in metastasizing axillary lymphnodes in breast cancer

Background: There is increasing evidences that a wide variety of malignancies, including breast cancer, may be driven by a small subset of ‘tumor-initiating cells’ or ‘cancer stem cells’ (CSC) which are able to form tumors in immunocompromised mice as well as to generate the phenotypic heterogeneity of the initial tumor. Enzyme aldehyde dehydrogenase (ALDH1) has been reported as a possible marker for mammary CSC. These cells are a source of tumor recurrence and metastasis, and are resistant to chemotherapy, radiotherapy and hormone therapy.

Objective: Assuming that the detection of CSC in axillary lymph nodes is more effective to predicting cancer outcome than the widely used detection of cancer cells in axillary lymph nodes, we measure ALDH1 levels to predict their presence into axillary lymph nodes on development of cancer and anticipate outcomes.

Methods: ALDH1 protein was detected by an immunohistochemical technique in 229 cases of breast cancer diagnosed from 2002 to 2011 Follow-up ranged from 11.5 months to 96.9 months, with a mean of 73.9 months. A survival assay was used to determine the relationship between distant metastatic rate and survival rate.

Results: ALDHl expression was detected in 79cases and the Positive rate in metastatic axillary lymph nodes was 34.5%. Negative ER, PR status were related to the ALDH1 positive cases(P = 0.012). See Table 1. Mortality rate between ALDH1 positive cases (50.8%) and negative cases (28.8%) were significantly different (P = 0.001). See Table 2. Further, survival analysis of recurrence-free survivals (RFS) and survival rate decreased significantly between ALDHl positive and negative cases (P = 0.001) (see table 2) and COX analysis shows that ALDH1 expression is an independent predictor of poor outcome in breast cancer(P = 0.011).

Discussion: What cancer stem cells migrate to the axillary nodes have more important prediction than that the matastesis of normal cancar cells in axillary node. It might be a role resulting in dying in breast cancer.

Recruitment of Grb2 and SHIP1 by the ITT-like motif of TIGIT suppresses granule polarization and cytotoxicity of NK cells

Activating and inhibitory receptors control natural killer (NK) cell activity. T-cell immunoglobulin and ITIM (immunoreceptor tyrosine-based inhibition motif) domain (TIGIT) was recently identified as a new inhibitory receptor on T and NK cells that suppressed their effector functions. TIGIT harbors the immunoreceptor tail tyrosine (ITT)-like and ITIM motifs in its cytoplasmic tail. However, how its ITT-like motif functions in TIGIT-mediated negative signaling is still unclear. Here, we show that TIGIT/PVR (poliovirus receptor) engagement disrupts granule polarization leading to loss of killing activity of NK cells. The ITT-like motif of TIGIT has a major role in its negative signaling. After TIGIT/PVR ligation, the ITT-like motif is phosphorylated at Tyr225 and binds to cytosolic adapter Grb2, which can recruit SHIP1 to prematurely terminate phosphatidylinositol 3-kinase (PI3K) and MAPK signaling, leading to downregulation of NK cell function. In support of this, Tyr225 or Asn227 mutation leads to restoration of TIGIT/PVR-mediated cytotoxicity, and SHIP1 silencing can dramatically abolish TIGIT/PVR-mediated killing inhibition.

Prolonged survival of allogeneic islets in cynomolgus monkeys after short-term triple therapy

Preclinical studies in nonhuman primates (NHP) are particularly useful to evaluate the safety and efficacy of new therapeutic proteins developed for use in clinical transplantation. We hypothesized that a treatment that selectively destroys activated cytopathic donor reactive T cells while sparing resting and immunoregulatory T cells in a mouse model might also produce long-term drug-free engraftment and tolerance without the hazards of lymphopenia in the challenging nonhuman primate islet allograft model. Short-term treatment with a regimen consisting of rapamycin, and IL-2.Ig plus mutant antagonist-type IL-15.Ig cytolytic fusion proteins (triple therapy) posttransplantation results in prolonged, drug-free engraftment of cynomolgus islet allografts. Moreover slow progressive loss of islet function in some recipients was not associated with obvious pathologic evidence of rejection.

Inter-sheet-effect-inspired graphene sensors: design, fabrication and characterization

With their sub-nanometer inter-sheet spacing, few-layer graphenes (FLGs) are alignment-free building blocks for nanosensors based on the inter-sheet effects. In this paper, we have tackled the challenges towards batch fabrication of inter-sheet graphene sensors through controlled layer engineering, edge tailoring and selective electrode fabrication on different atomic layers. An oxygen plasma etching (OPE) technique is developed to remove graphene layer by layer, enabling the batch fabrication of FLGs in a controllable fashion because of the faster speed and readiness of patterning of this process as compared to the conventional mechanical exfoliation. Vapor sensing experiments have shown that 'inter-sheet' sensors possess a higher sensitivity than conventional 'intra-sheet' ones. Vapor sensitivity is improved more than two times in normalized resistance changes by taking the 'inter-sheet' design upon exposure to 0.5% ethanol-nitrogen mixture and 500 Pa water vapor environments, respectively. These remarkable improvements can mainly be attributed to the inter-sheet effects such as electron tunneling, chemical doping, physical insertion and enhanced edge effects. Such effects may result from molecule adsorption/desorption, force/displacement, pressure, surface tension or thermal energy, and can potentially remarkably enrich the applicable transduction mechanisms.

Induced chirality through electromagnetic coupling between chiral molecular layers and plasmonic nanostructures

We report a new approach for creating chiral plasmonic nanomaterials. A previously unconsidered, far-field mechanism is utilized which enables chirality to be conveyed from a surrounding chiral molecular material to a plasmonic resonance of an achiral metallic nanostructure. Our observations break a currently held preconception that optical properties of plasmonic particles can most effectively be manipulated by molecular materials through near-field effects. We show that far-field electromagnetic coupling between a localized plasmon of a nonchiral nanostructure and a surrounding chiral molecular layer can induce plasmonic chirality much more effectively (by a factor of 10(3)) than previously reported near-field phenomena. We gain insight into the mechanism by comparing our experimental results to a simple electromagnetic model which incorporates a plasmonic object coupled with a chiral molecular medium. Our work offers a new direction for the creation of hybrid molecular plasmonic nanomaterials that display significant chiroptical properties in the visible spectral region.

Helicobacter pylori may cause otitis media with effusion: a pilot study

OBJECTIVES

To evaluate the presence of Helicobacter pylori (HP) in middle ear effusion from Chinese adult patients with otitis media with effusion (OME).

METHODOLOGY

A total of 60 aspiration samples collected from adult patients (ranging from 19 to 73 years old) were included in the study. The effusion samples aspirated from the patients' middle ears were analyzed with polymerase chain reaction (PCR) assay and cultured for 7 days under microaerobic conditions. Subsequently, Gram staining and urease testing were performed to identify HP.

RESULTS

Of the 60 middle ear effusion samples, 24 (40%) were shown to be HP-positive by PCR assay. Of these, seven specimens were confirmed HP-positive by both culture and urease test.

CONCLUSIONS

The present study clearly demonstrates the presence of HP in the middle ear effusion of some Chinese adult patients with OME. This finding suggests that HP may be involved in the etiology of OME. Additional studies are needed to investigate the exact role of HP in the pathogenesis of OME.

P2-11-09: EGFR Overexpression in Triple Negative Breast Cancer (TNBC) and Its Association with the Prognosis

Objective: The aim of this study is to investigate EGFR expression in Triple Negative Breast Cancer (TNBC), and to find the relationship between EGFR overexpression and prognosis of TNBC, further to clarify the significance of EGFR in TNBC and provide valuable information for TNBC therapy.

Methods: 42 triple ***negandection ***ssitive breast cancer patients(studying group) and 40 HER2(3+) breast cancer patients(controling group) who underwent surgery from January 2000 to December 2005 were analyzed. 82 cases of paraffin-embedded specimens were detected by Immunohistochemistry(IHC), fluorescence in situ hybridization(FISH) and polymerase chain reaction(PCR) to investigate the overexpression, amplification and mutation of EGFR gene. The distant-free survival(DFS) and overall survival(OS) of these patients were used to investigate the relationship between EGFR overexpression and the prognosis of TNBC.

Results: 34(43.9%) EGFR overexpression was observed in all cases, while gene amplification was only 7(9.1%) cases. No EGFR gene mutation was found in all cases. Overexpression of EGFR occurring in 57.1% patients in TNBC group and 25.0% patients in HER2 group, and we didn't found any correlation between EGFR overexpression and clinicopathology. 50(61.0%) patients relapsed (TNBC 28,HER2 22) and 27(32.9%) patients died(TNBC 18,HER2 9) were observed during the more than 5 years follow-up. The 5-year DFS was 57.1% and 77.5% respectively, the 5-year OS was 71.4% and 87.5% in TNBC and HER2 groups. In TNBC group, the survival of the EGFR-overexpressing group patients was significantly lower than that of the non-EGFR-overexpressing group patients (p=0.018 for DFS, p=0.026 for OS); In HER2 group, no statistical difference was found (p=0.079 for DFS, p=0.055 for OS).

Conclusions: This study showed that EGFR overexpression increased significantly in TNBC patients, which was no correlation with their clinico-pathological data. EGFR gene amplification was much less frequent than its overexpression. It suggested that EGFR gene amplification may not be the unique mechanism of EGFR overexpression in TNBC. There may be other possible mechanisms and pathways that cause EGFR overexpression. In addition, it may suggest that gefitinib therapy is useless in TNBC patients because we did not find any mutations in the tested exons of TNBC. EGFR overexpression may associate with a poor outcome of TNBC patients which suggest it could be a significant prognostic factor for TNBC patients. EGFR may play important role for molecular-targeting therapy of TNBC.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P2-11-09.

Granzyme K inhibits replication of influenza virus through cleaving the nuclear transport complex importin α1/β dimer of infected host cells

The influenza A virus is a causative agent of influenza, which infects human cells and uses host factors to accomplish viral genome replication as part of its life cycle. The nucleoprotein (NP) and PB2 of the influenza virus associate with importin α1 to gain access to the host nucleus through a ternary import complex. Killer cell-mediated cytotoxicity is the primary mechanism of eliminating the influenza virus. Here, we showed that lymphokine-activated killer cells participated in the elimination of the influenza virus. Granzyme (Gzm) K inhibition elevated viral replication in vitro and aggravated viral infection in vivo. We identified that importin α1 and its transport partner protein importin β are physiological substrates of GzmK. Proteolysis of these two substrates wrecked their association to generate the importin α1/β dimer and disrupted transportation of viral NP to the nucleus, leading to inhibition of influenza virus replication.

FADD cleavage by NK cell granzyme M enhances its self-association to facilitate procaspase-8 recruitment for auto-processing leading to caspase cascade

Granzyme M (GzmM), an orphan Gzm, is constitutively and abundantly expressed in innate effector natural killer cells. We previously demonstrated that GzmM induces caspase (casp)-dependent apoptosis and cytochrome c release from mitochondria. We also resolved the crystal structure for GzmM and generated its specific inhibitor. However, how GzmM causes casp activation has not been defined. Here we found that casp-8 is an initiator caspase in GzmM-induced casp cascade, which causes other casp activation and Bid cleavage. GzmM does not directly cleave procaspase-3 and Bid, whose processing is casp dependent. Casp-8 knockdown or deficient cells attenuate or abolish GzmM-induced proteolysis of procaspase-3 and Bid. Extrinsic death receptor pathway adaptor Fas-associated protein with death domain (FADD) contributes to GzmM-induced casp-8 activation. GzmM specifically cleaves FADD after Met 196 to generate truncated FADD (tFADD) that enhances its self-association for oligomerization. The oligomerized tFADD facilitates procaspase-8 recruitment to promote its auto-processing leading to casp activation cascade. FADD-deficient cells abrogate GzmM-induced activation of casp-8 and apoptosis as well as significantly inhibit lymphokine-activated killer cell-mediated cytotoxicity. FADD processing by GzmM can potentiate killing efficacy against tumor cells and intracellular pathogens.

Activation of glycogen synthase kinase-3 beta mediates β-amyloid induced neuritic damage in Alzheimer's disease

β-Amyloid (Aβ) plaques in Alzheimer (AD) brains are surrounded by severe dendritic and axonal changes, including local spine loss, axonal swellings and distorted neurite trajectories. Whether and how plaques induce these neuropil abnormalities remains unknown. We tested the hypothesis that oligomeric assemblies of Aβ, seen in the periphery of plaques, mediate the neurodegenerative phenotype of AD by triggering activation of the enzyme GSK-3β, which in turn appears to inhibit a transcriptional program mediated by CREB. We detect increased activity of GSK-3β after exposure to oligomeric Aβ in neurons in culture, in the brain of double transgenic APP/tau mice and in AD brains. Activation of GSK-3β, even in the absence of Aβ, is sufficient to produce a phenocopy of Aβ-induced dendritic spine loss in neurons in culture, while pharmacological inhibition of GSK-3β prevents spine loss and increases expression of CREB-target genes like BDNF. Of note, in transgenic mice GSK-3β inhibition ameliorated plaque-related neuritic changes and increased CREB-mediated gene expression. Moreover, GSK-3β inhibition robustly decreased the oligomeric Aβ load in the mouse brain. All these findings support the idea that GSK3β is aberrantly activated by the presence of Aβ, and contributes, at least in part, to the neuronal anatomical derangement associated with Aβ plaques in AD brains and to Aβ pathology itself.

Expression of smoothened in mouse embryonic maxillofacial development

Hedgehog (Hh) signaling plays many key roles in the development of Drosophila and vertebrate embryos including regulation of craniofacial development. The seven-transmembrane protein, smoothened (Smo) transduces the Hh signal across the plasma membrane as an essential receptor of PTCHED1/2. There are few studies that evaluate the detailed expression of Smo in mouse embryonic craniofacial development. We investigated the expression patterns of Smo during murine embryonic craniofacial development using in situ hybridization (ISH), studies of whole-mounts and sections, immunohistochemistry, quantitative real time PCR, and Western blot analysis. We found that Smo mRNA was expressed in the face of mouse embryos at 11 and 12.5 days post coitum (dpc). After 13.5 dpc, the expression decreased to a low level and was faintly detected after birth. Smo protein could be detected also in embryos at 11, 12.5, and 14.5 dpc. After 15.5 dpc, the expression was very faint and paralleled the gene expression studies. No expression was detected in whisker follicle during facial development and faint signal was detected in Meckel's cartilage. These findings concerning Smo expression should guide further investigation of sonic Hh signaling pathway gene function during maxillofacial development.

Ventilation and dampness in dorms and their associations with allergy among college students in China: a case-control study

To study the associations between dorm environment and occupants' health, a nested case-control study on 348 college students was carried out in 2006-2007 at Tianjin University, China. Two hundred and twenty-three dorm rooms where the 'cases' and 'controls' resided were inspected. Measured variables were ventilation rate, air temperature, and relative humidity indoors. Allergic symptoms in the last 12 months were self-reported by occupants. Adjusted odds ratios (AORs) of a 'localized moldy smell/moisture indicator' in 'special places' (e.g., in a room corner or close to the radiator under the window) for wheezing was 3.56 [95% Confident Interval (CI): 1.56-8.14] and for rhinitis 2.81 (95% CI: 1.32-5.97). The AOR of a low air change rate (below the median value of 0.7/h) for wheezing was 2.28 (95% CI: 1.38-3.75) and for dry cough 2.26 (95% CI: 1.08-4.75). The prevalence of students with allergic symptoms in dorm rooms decreased with increasing ventilation rate. The combination of a 'localized moldy/moisture indicator' and a low air change rate significantly increased the AOR of case status to 13.35 (95% CI: 3.73-47.83), compared to the reference condition with no-dampness and high ventilation rate (above the median). This supports the hypothesis that ventilation rate is an effect modifier for moisture problems and indoor pollutants.

Sequence variation and genetic diversity in the giant panda

About 336-444 bp mitochondrial D-loop region and tRNA gene were sequenced for 40 individuals of the giant panda which were collected from Mabian, Meigu, Yuexi, Baoxing, Pingwu, Qingchuan, Nanping and Baishuijiang, respectively. 9 haplotypes were found in 21 founders. The results showed that the giant panda has low genetic variations, and that there is no notable genetic isolation among geographical populations. The ancestor of the living giant panda population perhaps appeared in the late Pleistocene, and unfortunately, might have suffered bottleneck attacks. Afterwards, its genetic diversity seemed to recover to some extent.

Vagal Nerve Monitoring during Parapharyngeal Space Tumor Removal

The vagus nerve innervates the intrinsic and extrinsic laryngeal musculature as well as the complex pharyngeal plexus. Acute paralysis of this nerve results in dysfunctional speech, deglutition, and airway protection. These untoward effects, which lead to additional infectious and aerodigestive complications, may arise following manipulation of the vagus nerve during the surgical removal of a variety of neoplasms found in the parapharyngeal space.The vagal nerve has been intraoperatively monitored in an effort to maintain its anatomic and functional integrity. Bipolar hook-wire electrodes are introduced transcutaneously through the cricothyroid membrane and are guided into the vocalis muscle by an assistant performing direct laryngoscopy. Continuous, real-time monitoring of the vagal nerve is provided by audio and visual feedback to the operating surgeon. Potentially injurious stretching, heating, and compression of the nerve are easily detected, and monopolar stimulation of the nerve is used to map the nerve's course through the tumor bed.This presentation outlines our technique for vagal nerve monitoring in patients with tumors of the parapharyngeal space and intact preoperative vocal cord mobility. Selected cases are presented and illustrated through intraoperative and postoperative videotapes.

Formation of Buried Porous Silicon Structure by Hydrogen Plasma Immersion Ion Implantation

Plasma Immersion Ion Implantation (PIII) excels in several areas over conventional ion implantation, for example, higher dose, shorter implantation time, and lower overall cost. The technique can be used to fabricate buried porous silicon. In our experiment, hydrogen is implanted into Si by PIII at 5–30kV to form underlying porous silicon (PS) which emits light at an energy higher than the Si bandgap. The optical properties of the PS samples as measured by photoluminescence are quite good. The PHI technique therefore offers an alternative means to fabricate buried porous silicon structures which can potentially be used to fabricate optoelectronic devices in silicon.

Abstract P6-03-04: Opening, Dynamic Prospective Cohort Research on the Small Focus Less than 1.1cm Shown by B Ultrasound in Breast

BACKGROUND: Ultrasound is the most frequent clinical way to examine breast in China. Because Chinese have small and high density breasts, mammography can not show some lesions, and it costs too much. There are 5%-10% patients detected small, nonpalpable lesions by ultrasound in clinic and physical examination. Most of the lesions are very small, without typical characteristics of malignant or benign tumor. So many positive results bother doctors and patients. OBJECTIVE To find an appropriate way to detect breast cancer early and reduce unnecessary biopsy. METHODS: A Opening, dynamic prospective cohort research on the small focus less than 1.1cm shown by B ultrasound has been performed from 1 st January 2009. 791 cases and 1064 lesions were selected to the study group. All patients are female, from 35 to 75 years old. The lesions are from 0.25 cm to 1.1cm in ultrasound and less than grade 3 in mammography according to BI-RADS. The patients are divided to 2 groups according to the mammography grade of BI-RADS. The first subgroup concludes 260 cases with grade 3, and the second subgroup concludes 531 cases with less than grade 2. The patients who were more than grade 4 in ultrasound according to BI-RADS accepted biopsy as soon as they got into group. Other patients accept ultrasound per 3 months and mammography per year. We will do biopsy when the lesions rise up to 130% of the original size, and when the lesion reduce to 70% of the original size in consecutive two times examination on ultrasound , the patient will leave the group. RESULTS: Total 70 cases were performed biopsy during 17months. 2 cases (0.7%) without family history of breast cancer were breast cancer during biopsy in the first subgroup.2 cases (0.3%) with family history of breast cancer were mastopathy with atypia during the procedure of follow up—biopsy in the second subgroup. CONCLUSIONS: Most small lesions which are negative on mammography are benign and need not be performed resection. Use of mammography can reduce unnecessary biopsy in Chinese. Ultrasound and family history of breast cancer should be considered well.

the cases of screening and biopsy

Abstract P1-01-27: Level III and Interpectoral Lymph Nodes Involvement in Breast Cancer with Positive Axillary Lymph Nodes after Neoadjuvant Chemotherapy

Background: In the era of sentinel node biopsy (SNB), mainly aimed at local control, the axillary dissection (AD) was performed for breast cancer with positive node. It was argued that only level I/II lymph nodes dissection might be inadequate because nodes involvement was found in level III and interpectoral region when axillary node was positive. It is necessary to assess the extent of AD after modern preoperative axillary staging. The aim of this study was to investigate the incidence and associated factors of node involvement in level III/interpectoral region. Methods: A consecutive series of 338 core needle biopsy confirmed T0-2 invasive breast cancer cases were included in this study. Axillary node metastases were proved by ultrasound guided needle biopsy (NB) if ultrasonographic abnormal node was detected prior to SNB or by SNB if no abnormal node was detected. Cases of negative NB but positive SNB with image abnormal node were excluded. Prior to AD included level III and interpectoral lymph nodes, 4 to 8 cycles of neoadjuvant chemotherapy with anthrocyclin and/or taxane regimen were completed for each case. The chi-square test was used to determine the relation between level III/interpectoral lymph nodes metastases and clinicopathological factors. Multivariate logistic regression was analyzed for covariate selection. Results: A median of 19 axillary nodes was harvested per case (range: 5-46, average: 19.2). The pathologic complete response rate of axillary nodes was 35.3% (70/198) in NB positive subgroup. Level III and interpectoral lymph nodes were harvested in 76.9% (260/338) of cases (range: 1-8, average: 1.9, median: 1) and 49.7% (168/338) of cases (range: 1-10, average: 1.6, median: 1), respectively. The incidence of positive level III and interpectoral lymph nodes were 8.9% (30/338) and 8.9% (30/338), respectively. Node involvement of level III/interpectoral region was found in 13.3% (45/338) of these cases. The incidence of node involvement in level III/interpectoral region of NB positive subgroup (14.6%, 29/198) was not significantly higher compared with SNB positive subgroup (11.4%, 16/140, P=0.391). Increasing tumor size was significantly correlated with increasing likelihood of node involvement in level III/interpectoral region (T0-1: 6.3% vs T2: 16.7%, P=0.008). In SNB positive T0-1 subgroup, there was no positive node found in level III/interpectoral region. Multivariate analysis showed that tumor size was the only independent factors predicting node involvement in level III/interpectoral region (OR=3.488, 95%CI:1.427-8.528, P=0.006).

Conclusions: The incidence of node involvement in level III/interpectoral region was 13.3% of nodes positive T0-2 breast cancer treated with neoadjuvant chemotherapy. Tumor size may be the predictor of node involvement in this region.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P1-01-27.

Micromachining a miniaturized capillary electrophoresis-based chemical analysis system on a chip

Micromachining technology was used to prepare chemical analysis systems on glass chips (1 centimeter by 2 centimeters or larger) that utilize electroosmotic pumping to drive fluid flow and electrophoretic separation to distinguish sample components. Capillaries 1 to 10 centimeters long etched in the glass (cross section, 10 micrometers by 30 micrometers) allow for capillary electrophoresis-based separations of amino acids with up to 75,000 theoretical plates in about 15 seconds, and separations of about 600 plates can be effected within 4 seconds. Sample treatment steps within a manifold of intersecting capillaries were demonstrated for a simple sample dilution process. Manipulation of the applied voltages controlled the directions of fluid flow within the manifold. The principles demonstrated in this study can be used to develop a miniaturized system for sample handling and separation with no moving parts.

Amitosis-like nuclear division in erythrocytes of triploid rainbow trout Oncorhynchus mykiss

This work shows that the atypical erythrocytes in triploid rainbow trout Oncorhynchus mykiss were morphologically similar to those of toads. The nuclei of the cells can be bell-shaped, constricted or irregular. It is presumed that such nuclear division is probably amitosis.

Selective Effects of Glucose, Insulin and Leptin by Molecular Breast Cancer Subtype

Background: Type II diabetes and obesity are important risk factors for post-menopausal luminal A (LA) and triple negative (TN) pre-menopausal breast cancers, particularly in African American (AA) and Hispanic women. Breast cancer patients with these chronic metabolic diseases also have a worse prognosis, independent of other factors. We have published that metformin inhibits cell growth (S phase arrest) and induces apoptosis, only in TN cell lines in vivo and in vitro. It is less active, growth inhibitory (G1 arrest) and does not induce apoptosis in other breast cancer cell subtypes (Cell Cycle, 2009).Methods: We investigated the effects of glucose as a mitogen at physiologic (5mM), metabolic syndrome (7mM) or diabetic levels (10mM), with or without insulin (100 ng/ml) or leptin (100 ng/ml) using cell lines representing all molecular subtypes of breast cancer. Metformin was then used in combination with the above, to determine whether it would block the mitogenic or signaling effects of supraphysiological glucose, insulin or leptin.Results: The LA (MCF-7) and 2 of 5 TN cell lines (derived from AA patients; HCC 1806 and MDA 468) showed the most cell growth in response to glucose >5mM (75% for MCF-7, 30-50% for AA TN lines). Three TN cell lines from Caucasians (MDA231, HCC1937, BT20), the HER2 (SKBR3) and luminal B (BT-474) cells showed less growth induction with glucose >5mM. In TN lines only, glucose associated mitogenesis was associated with increased EGFR, pEGFR, IGF1R, pIGF1R, AKT and pAKT and decreases in AMPK, pAMPK, p38, IRS2, and the cyclins D1, E and A in a dose dependent manner. Metformin abrogated glucose induced cell growth and the aforementioned protein expression/phosphorylation changes involving EGFR, IGF1R, and AKT, increased AMPK and pAMPK and induced a profound reduction in Cyclin D1 across all glucose concentrations in TN cell lines from AA women. It reduced but did not eliminate glucose associated mitogenesis in the TN cell lines from Caucasian patients. Metformin had a more variable effect on cell lines of other molecular subtypes grown under high glucose conditions. The 5 TN breast cancer cell lines were uniformly resistant to both leptin and insulin associated mitogenesis, across a wide range of glucose concentrations. In contrast, both leptin and insulin significantly promoted LA breast cancer cell growth. These effects were resistant to metformin treatment. Leptin and insulin had the least growth promoting effects on HER2 breast cancer cell lines, whereas they induced modest growth induction in LB cell lines.Conclusions: All TN cell lines showed significant mitogenesis in response to glucose >5mM, whereas they were uniformly resistant to both leptin and insulin. The glucose associated mitogenesis was more pronounced in lines derived from AA patients, as were the anti-mitgenic effects of metformin. LA cells showed marked growth induction by glucose, leptin and insulin, whereas HER2 cell lines showed general resistance to all of these factors. These data suggest that metabolic and hormonal shifts with obesity and diabetes, as well as metformin response vary by the molecular subtype of breast cancer cells and ethnicity.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 5154.

Metformin Enhances Trastuzumab Efficacy and Overcomes Resistance in HER2 Type Breast Cancer Cells

Background: HER2 alterations occur in one-fourth of breast cancers and are associated with an aggressive tumor phenotype. The anti-HER2 agent trastuzumab reduces cell proliferation, angiogenesis, DNA repair and induces antibody-dependent cellular cytotoxicity. Objective response rates and median duration of response for eligible patients given trastuzumab alone is low (12-34% and 9 months respectively), hence, it is administered in combination with other agents. Mechanisms of trastuzumab resistance include: altered receptor antibody interactions, increased signaling through other EGFR type I growth factor receptors, modulation of p27 kip1 and increased insulin-like growth factor 1 receptor (IGF-1) signaling. We have reported that metformin inhibits HER2 expression, tyrosine kinase activity (phosphorylated HER2 at both auto- and Src- phosphorylation sites), AKT/mTOR signaling, Cyclin D1 and E2F1 with G1 arrest in HER2 overexpressing breast cancer cells. We sought to determine if metformin would enhance trastuzumab associated cytotoxicity and modulate acquired resistance in vitro.Methods: We used trastuzumab sensitive (SKBR3, BT474) and resistant cell lines (BT-474/HR20, SKBR3/P2, MCF-7/713 and MCF-7/HER2Δ16) to study the effects of metformin, metformin + trastuzumab and trastuzumab alone. Assays included MTS for proliferation, clonogenicity studies, Western blots, and pull down experiments with Western blots.Results: Trastuzumab sensitive breast cancer cells were less sensitive to metformin alone, compared to trastuzumab resistant HER2 subtype breast cancer cell lines. Trastuzumab sensitive cells showed enhanced growth and clonogenicity inhibition when treated by both metformin and trastuzumab. At the molecular level, these bi-treated cells showed decreases in HER2/pHER2, erbB3/perbB3, and inactivation of AKT and MAPk signaling. Metformin as low as 20mM increased the efficacy of trastuzumab. All HER2 resistant cell lines showed higher levels of IGF1R and HER2/IGF1R complexes, as compared to sensitive parental lines. In these resistant lines Metformin decreased cell proliferation and clonogenicity, HER2/IGF1R complexes (identified through pull down experiments) and protein expression of HER2/pHER2, erbB3/perbB3, IGF1R/pIGF1R as well as downstream signaling via Akt and IGF1 pathways. Metformin overcame trastuzumab resistance as demonstrated by growth and clonogenicity assays.Conclusions: HER2 amplified trastuzumab resistant breast cancer cells showed greater sensitivity to metformin than sensitive parental lines. Metformin reversed trastuzumab resistance and decreased HER2:IGF1R complexes, HER2/pHER2 and IGF1R expression, whereas sensitive parental lines showed no complex formation. These preclinical data suggest a combination of metformin and trastuzumab may have clinical benefit, improving the efficacy and reducing the emergence of or reversing trastuzumab resistance in HER2 positive breast cancer patients.Herceptin graciously provided by Genentech

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 1133.

Intracellular delivery and calcium transients generated in sonoporation facilitated by microbubbles

Ultrasound application in the presence of microbubbles is a promising strategy for intracellular drug and gene delivery, but it may also trigger other cellular responses. This study investigates the relationship between the change of cell membrane permeability generated by ultrasound-driven microbubbles and the changes in intracellular calcium concentration ([Ca(2+)](i)). Cultured rat cardiomyoblast (H9c2) cells were exposed to a single ultrasound pulse (1MHz, 10-15cycles, 0.27MPa) in the presence of a Definity(TM) microbubble. Intracellular transport via sonoporation was assessed in real time using propidium iodide (PI), while [Ca(2+)](i) and dye loss from the cells were measured with preloaded fura-2. The ultrasound exposure generated fragmentation or shrinking of the microbubble. Only cells adjacent to the ultrasound-driven microbubble exhibited propidium iodide uptake with simultaneous [Ca(2+)](i) increase and fura-2 dye loss. The amount of PI uptake was correlated with the amount of fura-2 dye loss. Cells with delayed [Ca(2+)](i) transients from the time of ultrasound application had no uptake of PI. These results indicate the formation of non-specific pores in the cell membrane by ultrasound-stimulated microbubbles and the generation of calcium waves in surrounding cells without pores.

Dampness in dorm rooms and its associations with allergy and airways infections among college students in China: a cross-sectional study

A cross-sectional study was carried out at Tianjin University campus, China, from February 21 to June 10, 2006, to survey the association between dampness in dorms, and allergy and airways infections among college students. The health and dampness conditions were self-reported by 3436 students living in 1511 dorm rooms located in 13 buildings on the campus. The buildings were selected according to their positions, construction periods and occupant densities. The symptoms involved wheezing, dry cough during night, rhinitis, eczema, cold/flu, ear inflammation, pneumonia and tuberculosis. The indoor moisture signs were mould/damp spots on walls, ceilings and floors; suspected or ever happened water damage; condensation on windowpane in winter and odours perceived by subjects themselves. There was a significant positive association between condensation and dry cough. Eczema was often reported in rooms with moisture problem. Dampness was a significant risk factor for common cold.

PRACTICAL IMPLICATIONS

Dampness problems in dorms of Chinese students are a risk factor for allergic symptoms, and hence there is a need for dorm environment improvement. Health problems related to ventilation and microbiology problems in dorms should be further studied.

Granzyme F induces a novel death pathway characterized by Bid-independent cytochrome c release without caspase activation

Granzyme F (GzmF) belongs to a unique group of granzymes in mice. Murine GzmF is highly expressed in NK3.1 cells and in lymphokine-activated killer (LAK) cells. However, the manner in which GzmF works in granule-mediated cytolysis is unknown. In this study, we first demonstrated that GzmF causes a novel cell death pathway. The death is characterized by an externalization of phosphatidylserine, by nuclear condensation, mitochondrial damage, cytochrome c (cyt c) release, caspase inactivation and single-stranded DNA nicking. GzmF-induced chromatin was incompletely condensed and segmented at the nuclear periphery. Cellular organelles were damaged and the cytoplasm showed an extensive vacuolization that is reminiscent of necroptosis. GzmF can cause rapid mitochondrial swelling, depolarization and reactive oxygen species accumulation. GzmF-induced death does not involve caspase activation, Bid cleavage or activation of DNA nickase NM23H1. GzmF-silenced LAK cells showed reduced cytotoxicity against caspase-inhibited target tumor cells. Moreover, cyt c release is independent of Bid or Bax/Bak. We further showed that GzmF impairs mitochondrial electron transport to abolish ATP generation. ATP decline may contribute to a failure of apoptosome formation, leading to caspase inactivation.

Case mix, quality and high-cost kidney transplant patients

A better understanding of high-cost kidney transplant patients would be useful for informing value-based purchasing strategies by payers. This retrospective cohort study was based on the Medicare Provider Analysis and Review (MEDPAR) files from 2003 to 2006. The focus of this analysis was high-cost kidney transplant patients (patients that qualified for Medicare outlier payments and 30-day readmission payments). Using regression techniques, we explored relationships between high-cost kidney transplant patients, center-specific case mix, and center quality. Among 43 393 kidney transplants in Medicare recipients, 35.2% were categorized as high-cost patients. These payments represented 20% of total Medicare payments for kidney transplantation and exceeded $200 million over the study period. Case mix was associated with these payments and was an important factor underlying variation in hospital payments high-cost patients. Hospital quality was also a strong determinant of future Medicare payments for high-cost patients. Compared to high-quality centers, low-quality centers cost Medicare an additional $1185 per kidney transplant. Payments for high-cost patients represent a significant proportion of the total costs of kidney transplant surgical care. Quality improvement may be an important strategy for reducing the costs of kidney transplantation.

Superparamagnetic iron oxide nanoparticle-labeled cells as an effective vehicle for tracking the GFP gene marker using magnetic resonance imaging

BACKGROUND

Detection of a gene using magnetic resonance imaging (MRI) is hindered by the magnetic resonance (MR) targeting gene technique. Therefore it may be advantageous to image gene-expressing cells labeled with superparamagnetic iron oxide (SPIO) nanoparticles by MRI.

METHODS

The GFP-R3230Ac (GFP) cell line was incubated for 24 h using SPIO nanoparticles at a concentration of 20 microg Fe/mL. Cell samples were prepared for iron content analysis and cell function evaluation. The labeled cells were imaged using fluorescent microscopy and MRI.

RESULTS

SPIO was used to label GFP cells effectively, with no effects on cell function and GFP expression. Iron-loaded GFP cells were successfully imaged with both fluorescent microscopy and T2*-weighted MRI. Prussian blue staining showed intracellular iron accumulation in the cells. All cells were labeled (100% labeling efficiency). The average iron content per cell was 4.75+/-0.11 pg Fe/cell (P<0.05 versus control).

DISCUSSION

This study demonstrates that the GFP expression of cells is not altered by the SPIO labeling process. SPIO-labeled GFP cells can be visualized by MRI; therefore, GFP, a gene marker, was tracked indirectly with the SPIO-loaded cells using MRI. The technique holds promise for monitoring the temporal and spatial migration of cells with a gene marker and enhancing the understanding of cell- and gene-based therapeutic strategies.

Dampness at dorm and its associations with allergy and airways infection among college students in China: a cross-sectional study

A cross-sectional study was carried out at Tianjin University campus, China, from February 21 to June10, 2006, to survey the association between dampness in dorms and allergy and airways infection among college students. The health and dampness condition were self-reported by 3436 students living in 1511 dorm rooms located in 13 buildings on the campus. The buildings were selected according to their positions, construction periods and occupant densities. The allergy and airways infection symptoms involved wheezing, dry cough during night, rhinitis, eczema, cold/flu, ear inflammation, pneumonia and tuberculosis. The indoor moisture signs were mould/damp spots on walls, ceilings and floors; suspected or ever happened water damage; condensation on windowpane in winter and odours perceived by subjects themselves. This study showed there was significantly positive association between condensation and dry cough. Eczema was often reported in rooms with suspected moisture problem. Dampness was a significantly risk factor for common cold.

PRACTICAL IMPLICATIONS

This paper indicated that dampness problem at dorms of Chinese students was a risk factor in irritating allergic symptoms, and hence there is a need for dorm environment improvement. The ventilation and microbiology problems in dorm environment corresponding to dampness should be further studied, especially when it is associated to occupants' health.

Expression of ER-a36, a novel variant of estrogen receptor a, and resistance to tamoxifen treatment in breast cancer

Abstract #3037

Background: Recently, a 36 kDa variant of estrogen receptor a (ER-a66), ER-a36, has been identified and cloned. ER-a36 predominantly localizes on the plasma membrane and in the cytoplasm and mediates a membrane-initiated “nongenomic” signaling pathway. In this study, we investigated the association between ER-a36 expression and tamoxifen resistance in breast cancer patients.&#x2028; Methods: ER-a36 protein expression in tumors from 710 breast cancer patients with a median follow-up of 7.9 years was assessed using immunohistochemistry (IHC) assay. Survival curves were compared using the log-rank test and multivariate analysis was performed using Cox model. All statistical tests were two-sided.&#x2028; Results: Among the patients with ER-a66 positive tumors who received tamoxifen treatment (n=307), overexpression of ER-a36 was associated with poorer disease-free survival (DFS) and disease-specific survival (DSS) and remained as an unfavorable independent factor of survival in multivariate analyses (DFS: HR=2.27; 95% CI= 1.40 to 3.68; P=. 001; DSS: HR=2.42; 95% CI= 1.37 to 4.28; P= .002). In contrast, among patients with ER-a66 positive tumors who did not receive tamoxifen (n=129), ER-a36 expression was not associated with survival, indicating a correlation between ER-a36 expression and tamoxifen resistance. Furthermore, ER-a36 expression was not associated with survival in ER-a66 negative tumors whether the patients received tamoxifen (n=73) or not (n=149). Our in vitro experiments with MCF7/ER36 cells also confirmed that high ER-a36 expression resulted in tamoxifen resistance.&#x2028; Conclusions: Patients with ER-a66 positive tumors that also express high levels of ER-a36 are less likely to benefit from tamoxifen treatment. ER-a36 is an important predictive marker for tamoxifen therapy in ER-a66 positive breast cancer patients.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 3037.

Metabolomics of basal breast carcinomas: a potential target for treatment intervention

Abstract #6026

Breast cancers of the basal subtype (ER, PR and HER2 negative; EGFR and/or CK5/6 positive) are typically high grade, rapidly proliferative, associated with a poor outcome and are resistant to many chemotherapeutic regimens. They occur more frequently in women with BRCA-1 mutations, African Americans and obese individuals. At the molecular level, basal cancers have impairment of BRCA-1 and p53 signaling and are driven, in part, through EGFR which activates the PI3K/AKT/mTOR pathways. Treatment of basal carcinoma cell lines with the FDA approved anti-diabetic drug metformin significantly reduces cellular proliferation, induces cell cycle arrest (late G1/S phase) and apoptosis in vivo and in vitro. Similar effects were not observed in breast cancer cells of the luminal A, B or HER2 subtypes. Metformin induces a wide spectrum of metabolic and molecular changes in basal carcinoma cell lines in vitro, including: a reduction in glucose uptake, enhanced lactate release, a decrease in cellular proliferation and colony formation, a decrease in EGFR, phospho-EGFR and downstream signaling including pAKT, pMAPK and psrc, inhibition of cyclins D1 and E, reduced E2F1, PARP cleavage and activation of caspases 3, 8 and 9 in a dose and time dependent manner. Nude mice with basal cell line MDA-MB-231 xenografts treated with metformin showed significantly reduced tumor growth and prolonged survival as compared to control untreated mice. Pre-treatment with metformin prior to xenograft inoculation reduced both tumor formation and growth as compared to mice treated with metformin after implantation or untreated control mice, suggesting that metformin may have some use in basal cancer prevention. Epidemiologic data has shown that women treated with metformin have a reduced rate of breast cancer and, for those patients with breast cancer, an improved disease free and overall survival. In aggregate, these data suggest that further study of metformin to prevent or treat breast cancer in some patient subgroups may be indicated.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 6026.

Torsional waves propagation along a waveguide of arbitrary cross section immersed in a perfect fluid

Guided torsional waves in a bar with a noncircular cross section have been exploited by previous researchers to measure the density of fluids. However, due to the complexity of the wave behavior in the noncircular cross-sectional shape, the previous theory can only provide an approximate prediction; thus the accuracy of the measurement has been compromised. In this paper, a semianalytical finite element method is developed to model accurately the propagation velocity and leakage of guided waves along an immersed waveguide with arbitrary noncircular cross section. An accurate inverse model is then provided to measure the density of the fluid by measuring the change of the torsional wave speed. Experimental results obtained with a rectangular bar in a range of fluids show very good agreement with the theoretical predictions. Finally, the potentials to use the model for sensor optimization are discussed.