Abstract 4075: Proportion of breast cancer stem cells in fine needle aspirates co-relates with the marker of metastatic outcome TMEM

Cell surface biomarkers CD44, CD24 and CD133 and intracellular marker ALDH1 have recently been used to identify breast cancer stem cells. A very small number of these cancer stem cells can initiate a tumor growth and cause it to metastasize. The micro-anatomical sites of hematogenous dissemination of breast cancer cells called Tumor MicroEnvironment of Metastasis (TMEM) have been described in formalin-fixed paraffin-embedded invasive ductal carcinomas from patients. These sites are defined as the direct apposition of tumor cells and perivascular macrophages and are visualized using triple immunohistochemistry for CD68, CD31 and Mena to identify the macrophages, endothelial cells and invasive tumor cells respectively. The identification of TMEM sites is clinically important because TMEM density is a predictor of metastatic outcome. Migratory subpopulation of tumor cells has been shown to be enriched for cancer stem cells.

We have performed flow cytometry to identify CD44high/CD24low cells, mRNA fluorescent in situ hybridization (FISH) and qRT-PCR to identify CD133 and ALDH1 expression in breast cancer cells in 50 samples of invasive ductal carcinoma obtained from patients’ cancer excisions by fine needle aspiration (FNA) before formalin fixation. FNA is a minimally invasive method that uses 26 gauge needles to collect discohesive cancer cells primarily by capillary action. The stem cell marker expression was then compared to TMEM scores obtained from the very same cancer excisions after formalin fixation and paraffin embedding.

Our results show very strong correlation between the percentage of CD44high/CD24low cells with TMEM scores (r = 0.91), as well as the percentage of CD133 and ALDH1 expressing cells with TMEM scores (r = 0.88 and 0.86 respectively). We validated the results obtained by FISH with the direct qRT-PCR for CD133 and ALDH1 in the FNA samples. The correlation of CD133 and ALDH1 expression obtained by qRT-PCR with TMEM score was again very strong (r = 0.76 and 0.73 respectively).

Our findings here and those previously reported for migratory tumor cells demonstrate that TMEM rich microenvironments are enriched for cancer stem cells and partially explain positive correlation of TMEM scores with metastasis in patients. They also suggest that the assessment of stem cell proportion in breast cancers can be assessed in FNA samples. The clinical value of stem cell assessment using this approach for prognostic and predictive is under investigation.

Citation Format: Maja H. Oktay, Eli Grunblatt, Sweta Roy, Nathan Agi, Esther Adler, Joan G. Jones, John S. Condeelis, Sumanta Goswami. Proportion of breast cancer stem cells in fine needle aspirates co-relates with the marker of metastatic outcome TMEM. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 4075. doi:10.1158/1538-7445.AM2015-4075

Abstract 5125: Imaging the tumor microenvironment of metastasis reveals the mechanism of transient blood vessel permeability and tumor cell intravasation

Sites of direct contact between a macrophage, a tumor cell and endothelial cell [Tumor MicroEnvironment of Metastasis (TMEM)], correlates with metastasis in breast cancer patients independently of other clinical prognostic indicators suggesting a direct role for TMEM function in hematogenous dissemination. Here we show, using intravital high-resolution two-photon microscopy, that tumor cell intravasation occurs only at TMEM. Tumor cell intravasation occurs concurrently with transient, local vascular permeability at TMEM in an autochthonous mouse mammary carcinoma model and a human patient-derived xenograft model. Ablation of the presence or activity of the TMEM associated macrophages blocks tumor cell intravasation at TMEM demonstrating an essential role of perivascular macrophages in TMEM function. A subset of TMEM macrophages are identified as Tie2-expressing macrophages that are characterized by F4/80+/CD11b+/CD68+/MRC1+/Tie2Hi/VEGFAHi/CD11c-. VEGFA signaling from Tie2Hi TMEM-associated macrophages causes the local loss of vascular junctions resulting in transient vascular permeability and tumor cell intravasation at TMEM. Macrophage-specific ablation of VEGFA results in increased vascular junction stability and inhibition of intravasation, demonstrating that vascular junction dissolution at VEGFAHi/Tie2Hi TMEM-associated macrophages leads to vascular permeability and tumor cell intravasation. Inhibition of Tie2 with the first in class small molecular inhibitor rebastinib impairs TMEM function leading to a reduction in vascular permeability, tumor cell dissemination and metastasis. Further, rebastinib inhibition of Tie2 blocks tumor cell extravasation and metastatic growth in the lungs.

Together, the findings that TMEM macrophages mediate vascular permeability and tumor cell intravasation demonstrate an essential role for TMEM within the primary mammary tumor as sites of tumor cell dissemination. These data reveal the mechanism of tumor cell intravasation in breast cancer, explain the prognostic value of TMEM density in predicting distant metastatic recurrence in breast cancer patients and document a strategy for inhibition of dissemination.

This research is supported by the Department of Defense Breast Cancer Research Program under award number BC120227 (ASH), NIH CA100324 (JSC) and the Integrated Imaging Program.

Citation Format: Allison S. Harney, Esther N. Arwert, David Entenberg, Yarong Wang, Peng Guo, Bin-Zhi Qian, Bryan D. Smith, Jeffrey W. Pollard, Joan G. Jones, Daniel L. Flynn, John S. Condeelis. Imaging the tumor microenvironment of metastasis reveals the mechanism of transient blood vessel permeability and tumor cell intravasation. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 5125. doi:10.1158/1538-7445.AM2015-5125

Invasive breast carcinoma cells from patients exhibit MenaINV- and macrophage-dependent transendothelial migration

Metastasis is a complex, multistep process of cancer progression that has few treatment options. A critical event is the invasion of cancer cells into blood vessels (intravasation), through which cancer cells disseminate to distant organs. Breast cancer cells with increased abundance of Mena [an epidermal growth factor (EGF)-responsive cell migration protein] are present with macrophages at sites of intravasation, called TMEM sites (for tumor microenvironment of metastasis), in patient tumor samples. Furthermore, the density of these intravasation sites correlates with metastatic risk in patients. We found that intravasation of breast cancer cells may be prevented by blocking the signaling between cancer cells and macrophages. We obtained invasive breast ductal carcinoma cells of various subtypes by fine-needle aspiration (FNA) biopsies from patients and found that, in an in vitro transendothelial migration assay, cells that migrated through a layer of human endothelial cells were enriched for the transcript encoding Mena(INV), an invasive isoform of Mena. This enhanced transendothelial migration required macrophages and occurred with all of the breast cancer subtypes. Using mouse macrophages and the human cancer cells from the FNAs, we identified paracrine and autocrine activation of colony-stimulating factor-1 receptor (CSF-1R). The paracrine or autocrine nature of the signal depended on the breast cancer cell subtype. Knocking down Mena(INV) or adding an antibody that blocks CSF-1R function prevented transendothelial migration. Our findings indicate that Mena(INV) and TMEM frequency are correlated prognostic markers and CSF-1 and Mena(INV) may be therapeutic targets to prevent metastasis of multiple breast cancer subtypes.

Abstract 4940: Perivascular macrophages induce localized, transient blood vessel permeability and tumor cell intravasation

Metastasis is a multistep process involving tumor and stromal cells. The microanatomical site consisting of a perivascular macrophage interacting with a Mena over-expressing tumor cell has been named the “tumor microenvironment of metastasis” (TMEM). TMEM density predicts distant metastatic recurrence in breast cancer patients making the study of TMEM function essential. In spontaneous orthotopic mouse mammary tumors (MMTV-PyMT), as the tumor progresses to malignancy tumor cells have increased Mena expression and assemble TMEM. TMEM assembly is correlated with elevated levels of circulating tumor cells and lung metastases, indicating a functional role for TMEM in tumor cell dissemination. High-resolution multiphoton-based microscopy at single cell resolution has revealed transient blood vessel permeability events at TMEM, marked by the extravasation of otherwise impermeable serum markers such as Qdots and fluorescent 155 kDa dextran. In proximity to sites of permeability there is increased tumor cell and macrophage motility towards the blood vessel, and local intravasation of tumor cells. Blocking macrophage function results in decreased blood vessel permeability and decreased numbers of circulating tumor cells. TMEM-associated macrophages produce VEGF-A, and blocking VEGF-A reduces blood vessel permeability and circulating tumor cells. The observation that TMEM mediates tumor cell intravasation through localized blood vessel permeability in live animals demonstrates that TMEM is a key metastatic microenvironment in the primary tumor, explains the prognostic value of TMEM density in predicting distant metastatic recurrence in breast cancer patients and suggests a potentially valuable re-tasking of existing anti-angiogenesis drugs.

This research is supported by the Department of Defense [Breast Cancer Research Program)] under award number BC120227 (ASH).

Note: This abstract was not presented at the meeting.

Citation Format: Allison S. Harney, Esther N. Arwert, David Entenberg, Yarong Wang, Joan G. Jones, John S. Condeelis. Perivascular macrophages induce localized, transient blood vessel permeability and tumor cell intravasation. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4940. doi:10.1158/1538-7445.AM2014-4940

Tumor microenvironment of metastasis and risk of distant metastasis of breast cancer

BACKGROUND

Tumor microenvironment of metastasis (TMEM), consisting of direct contact between a macrophage, an endothelial cell, and a tumor cell, has been associated with metastasis in both rodent mammary tumors and human breast cancer. We prospectively examined the association between TMEM score and risk of distant metastasis and compared risk associated with TMEM score with that associated with IHC4.

METHODS

We conducted a case-control study nested within a cohort of 3760 patients with invasive ductal breast carcinoma diagnosed between 1980 and 2000 and followed through 2010. Case patients were women who developed a subsequent distant metastasis; control subjects were matched (1:1) on age at and calendar year of primary diagnosis. TMEM was assessed by triple immunostain and IHC4 by standard methods; slides were read by pathologists blinded to outcome. Odds ratios (ORs) and 95% confidence intervals (CIs) were estimated using logistic regression, adjusted for clinical variables. A Receiver Operating Characteristic analysis was performed, and the area under the curve was estimated. All statistical tests were two-sided.

RESULTS

TMEM score was associated with increased risk of distant metastasis in estrogen receptor (ER)(+)/human epidermal growth factor receptor (HER2)(-) tumors (multivariable OR high vs low tertile = 2.70; 95% CI = 1.39 to 5.26; P trend = .004), whereas IHC4 score had a borderline positive association (OR10 unit increase = 1.06; 95% CI = 1.00 to 1.13); the association for TMEM score persisted after adjustment for IHC4 score. The area under the curve for TMEM, adjusted for clinical variables, was 0.78. Neither TMEM score nor IHC4 score was independently associated with metastatic risk overall or in the triple negative or HER2(+) subgroups.

CONCLUSIONS

TMEM score predicted risk of distant metastasis in ER(+)/HER2(-) breast cancer independently of IHC4 score and classical clinicopathologic features.

Abstract P6-02-04: TMEM (Tumor MicroEnvironment of Metastasis) in human breast cancer is a blood vessel associated intravasation microenvironment unrelated to lymphatics

In breast cancer, both lymph node and distant metastasis represent dissemination of tumor cells from a primary site, but the mechanism of spread and the subsequent risk of mortality may not be the same. Historically, lymphatic spread has been documented both descriptively, as presence or absence of lymphovascular invasion (LVI), and as a formal part of TNM staging. Until recently, however, there has been no way to directly assess the risk of hematogenous dissemination by the primary tumor.

Observations from multiphoton-based intravital imaging of rodent models of breast cancer and the analysis of Mena function in tumor cells in vivo have characterized an intravasation microenvironment (ME) involved in the systemic dissemination of tumor cells from primary breast tumors. We have identified the corresponding structure in FFPE tissue and called it TMEM (Tumor MicroEnvironment of Metastasis). This microanatomic landmark is defined as the direct apposition of a Mena-overexpressing intravasation competent carcinoma cell, a perivascular macrophage, and an endothelial cell. In a case control study of 30 case-control pairs, where each matched pair differed only in their metastatic status – non-metastatic vs. metastatic – we found that the density of TMEM was significantly associated with development of systemic metastasis (p = 0.00006).

The relationship of hematogenous- and lymphatic-mediated tumor cell spread is not understood. Using the previously described cohort in which we showed that TMEM was associated with metastasis, the purpose of this study was to 1) assess intratumoral lymphatic density, 2) determine if TMEM- lymphatic structures associated with lymphatics exist, and 3) determine if TMEM- lymphatic structures correlate with systemic metastatic risk. Cases were stained with a triple immunostain identical to that used in our earlier study except that D2-40 (a lymphatic marker) was used, rather than CD31 (a blood vessel marker). The marker for macrophages (CD68) and invasive tumor cells (Mena) remained the same. Two pathologists, blinded to outcome, evaluated the presence or absence of intratumoral lymphatics and quantitated the number of TMEM-lymphatic structures per 10 high power (400x) fields in areas of highest intratumoral lymphatic density. A TMEM-lymphatic structure was defined as the direct apposition of a lymphatic (D2-40) endothelial cell with a macrophage and invasive tumor cell.

Intratumoral lymphatics were absent in a majority of tumors in each of the 2 groups (18 of 30 non-metastatic, 16 of 30 metastatic; p = 0.6). TMEM-lymphatic structures were rare and were equally present in the 2 groups (3 metastatic and 3 non-metastatic cases). Using the Wilcoxon (paired) signed-rank test, we found no significant difference in the density of these structures between the two groups (p = 0.4). Furthermore, TMEM-lymphatic structures did not correlate with the presence of lymph node metastases (p = 0.8). We conclude that lymphatic vessels do not participate in the TMEM assembly that has been associated with hematogenous metastasis. TMEM density assessment reflects a hematogenous intravasation ME and offers a novel approach to the assessment of metastatic risk.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P6-02-04.

Abstract 1410: TMEM (Tumor MicroEnvironment of Metastasis) in human breast cancer is a blood vessel associated intravasation microenvironment unrelated to lymphatics

Observations from intravital imaging (Wyckoff et al. Can Res 2007) and the analysis of Mena function in tumor cells in vivo (Roussos et al. JCS 2011) has characterized an intravasation microenvironment (ME) involved in the systemic dissemination of tumor cells from primary breast tumors. We have identified the corresponding structure in FFPE tissue and called it TMEM (Tumor MicroEnvironment of Metastasis). This microanatomic landmark is defined as the direct apposition of a Mena-overexpressing intravasation competent carcinoma cell, a perivascular macrophage, and an endothelial cell. In a case control study of 60 patients, where each matched pair differed only in their metastatic status - non-metastatic vs. metastatic - the density of TMEM was assessed and found to be significantly associated with development of systemic metastasis (p = 0.00006) (Robinson et al. Clin Can Res 2009). Although lymph node status is considered an important prognostic factor in breast cancer, the direct involvement of lymphatics in systemic tumor cell dissemination from primary tumors has not been demonstrated. In addition, the relationship of hematogenous- and lymphatic-mediated tumor cell spread is not understood. The purpose of this study was to 1) assess intratumoral lymphatic density in this same cohort, 2) determine if TMEM-like structures associated with lymphatics exist, and 3) determine if lymphaticTMEM-like structures correlate with systemic metastatic risk. Cases were stained with a triple immunostain identical to that used in the Robinson et al. study except that D2-40 (a lymphatic marker) was used, rather than CD31 (a blood vessel marker). The marker for macrophages (CD68) and invasive tumor cells (Mena) remained the same. Two pathologists, blinded to outcome, evaluated for the presence or absence of intratumoral lymphatics and quantitated the number of TMEM-like structures per 10 high power (400x) fields in areas of highest intratumoral lymphatic density. A TMEM-like structure was defined as the direct apposition of a lymphatic (D2-40) endothelial cell with a macrophage and invasive tumor cell. Intratumoral lymphatics were absent in a majority of tumors in each of the 2 groups (18 of 30 non-metastatic, 16 of 30 metastatic; p=0.6). TMEM-like structures were rare and were equally present in the 2 groups (3 metastatic and 3 non-metastatic cases). Using the Wilcoxon (paired) signed-rank test, we found no significant difference in the density of these structures between the two groups (p = 0.4). Furthermore, TMEM-like structures did not correlate with the presence of lymph node metastases (p=0.8). We conclude that lymphatic vessels do not participate in the TMEM assembly that has been associated with hematogenous metastasis. TMEM density assessment reflects a hematogenous intravasation ME and offers a novel approach to the assessment of metastatic risk.

Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 1410. doi:1538-7445.AM2012-1410

Correlated immunohistochemical and cytological assays for the prediction of hematogenous dissemination of breast cancer

Although metastasis is a major cause of death from breast cancer, our ability to predict which tumors will metastasize is limited (American Cancer Society 2010). Proper assessment of metastatic risk and elucidating the underlying mechanisms of metastasis will help personalize therapy and may provide insight into potential therapeutic targets. Traditionally, histologic grading, staging, hormone receptors, HER2/Neu, and proliferation assays have been the gold standard on which oncologists based their treatment decisions. However, all of these are indirect measures of metastatic risk. Recent insights from intravital imaging directly address questions of mechanism and have led to a new way of using histologic and cytologic material to assess metastatic risk. This review describes the tumor microenvironment model of invasion and intravasation, as well as an emerging histopathologic application based on this model. In particular, the authors describe a new immunohistochemical approach to the assessment of metastatic risk based on the density of intravasation microenvironment sites called the tumor microenvironment of metastasis. In addition, they describe an isoform assay for the actin regulatory protein Mena using fine needle aspiration samples and the details about how these 2 assays may be applied in clinical practice in a synergistic way to assess the risk of metastasis.

A Cohort Study of p53 Mutations and Protein Accumulation in Benign Breast Tissue and Subsequent Breast Cancer Risk

Mutations in the p53 tumor suppressor gene and accumulation of its protein in breast tissue are thought to play a role in breast carcinogenesis. However, few studies have prospectively investigated the association of p53 immunopositivity and/or p53 alterations in women with benign breast disease in relation to the subsequent risk of invasive breast cancer. We carried out a case-control study nested within a large cohort of women biopsied for benign breast disease in order to address this question. After exclusions, 491 breast cancer cases and 471 controls were available for analysis. Unconditional logistic regression was used to estimate odds ratios (OR) and 95% confidence intervals (95% CI). Neither p53 immunopositivity nor genetic alterations in p53 (either missense mutations or polymorphisms) was associated with altered risk of subsequent breast cancer. However, the combination of both p53 immunopositivity and any p53 nucleotide change was associated with an approximate 5-fold nonsignificant increase in risk (adjusted OR 4.79, 95% CI 0.28-82.31) but the confidence intervals were extremely wide. Our findings raise the possibility that the combination of p53 protein accumulation and the presence of genetic alterations may identify a group at increased risk of breast cancer.

Mena invasive (Mena(INV)) and Mena11a isoforms play distinct roles in breast cancer cell cohesion and association with TMEM

Mena, an actin regulatory protein, functions at the convergence of motility pathways that drive breast cancer cell invasion and migration in vivo. The tumor microenvironment spontaneously induces both increased expression of the Mena invasive (Mena(INV)) and decreased expression of Mena11a isoforms in invasive and migratory tumor cells. Tumor cells with this Mena expression pattern participate with macrophages in migration and intravasation in mouse mammary tumors in vivo. Consistent with these findings, anatomical sites containing tumor cells with high levels of Mena expression associated with perivascular macrophages were identified in human invasive ductal breast carcinomas and called TMEM. The number of TMEM sites positively correlated with the development of distant metastasis in humans. Here we demonstrate that mouse mammary tumors generated from EGFP-Mena(INV) expressing tumor cells are significantly less cohesive and have discontinuous cell-cell contacts compared to Mena11a xenografts. Using the mouse PyMT model we show that metastatic mammary tumors express 8.7 fold more total Mena and 7.5 fold more Mena(INV) mRNA than early non-metastatic ones. Furthermore, Mena(INV) expression in fine needle aspiration biopsy (FNA) samples of human invasive ductal carcinomas correlate with TMEM score while Mena11a does not. These results suggest that Mena(INV) is the isoform associated with breast cancer cell discohesion, invasion and intravasation in mice and in humans. They also imply that Mena(INV) expression and TMEM score measure related aspects of a common tumor cell dissemination mechanism and provide new insight into metastatic risk.

Impaired insulin stimulation of muscular ATP production in patients with type 1 diabetes

OBJECTIVE

in type 2 diabetic patients and their first-degree relatives, insulin resistance (IR) is associated with impairment of insulin-stimulated myocellular glucose-6-phosphate (g6p) and unidirectional flux through ATP synthase (fATP), suggesting the presence of inherited abnormal mitochondrial oxidative fitness. We hypothesized that patients with long-standing type 1 diabetes may also exhibit insulin resistance as well as lower fATP.

DESIGN

this single-centre trial was registered at ClinicalTrials.gov (NCT00481598).

SUBJECTS

we included eight nonobese type 1 diabetic patients (mean diabetes duration: 17 years) with near-target glycaemic control [haemoglobin A1c (HbA1c): 6.8 ± 0.4%] during treatment with continuous subcutaneous insulin infusion pumps and eight healthy volunteers (HbA1c: 5.4 ± 0.2%) of comparable age, body mass and level of physical activity.

OUTCOME MEASURES

myocellular fATP, g6p and intramyocellular lipid content (IMCL) were measured with (1) H/(31) P magnetic resonance spectroscopy during fasting and hyperinsulinaemic-euglycaemic clamp tests.

RESULTS

fasting fATP, g6p and IMCL did not differ between groups. During stimulation by insulin, type 1 diabetic patients exhibited approximately 50% (P < 0.001) lower whole-body glucose disposal along with approximately 42% (P = 0.003) lower intramyocellular g6p and approximately25% (P = 0.024) lower fATP. Insulin-stimulated fATP correlated positively with whole-body insulin sensitivity (R = 0.706, P = 0.002) and negatively with HbA1c (R = -0.675, P = 0.004).

CONCLUSIONS

despite documented near-target glycaemic control for 1 year, nonobese patients with long-standing type 1 diabetes can exhibit insulin resistance. This associates with lower insulin-stimulated flux through muscular ATP synthase which could result from glucose toxicity.

Abstract P3-10-16: Quantitative Subtractive Immunofluorescence To Develop a Surrogate for Mena Inv(asive) Isoform Is Associated with Poor Outcome in Breast Cancer

Introduction:

Previous work has shown that the inv isoform of Mena, an actin binding protein, is associated with invasion at the cellular level and metastasis in the context of the microenvironment in both animal models and humans (Robinson, B.D. et al. Clin Cancer Res 15, 2433-2441 (2009). However, the prognostic value for metastasis of MenaINV itself is unknown because there is no antibody that directly recognizes this isoform. Here we describe a method to assess a surrogate for MenaINV by measuring total Mena and subtracting the levels of the 11a (non-invasive) isoform. Method: Total Mena and Mena11a were measured in two independent retrospective breast cancer cohorts with 20 year follow-up using tissue microarray and quantitative immunofluorescence (AQUA) technology in a previously described multiplexed mode. AQUA scores for each marker were converted into z scores followed by subtraction of Mena 11a (noninvasive form of Mena) from total Mena (invasive and non-invasive) = Mena(inv) surrogate. This was calculated for each patient and correlated with clinical and pathological characteristics as well as disease-free survival in both cohorts.

Results: In the older Yale cohort, Kaplan Meier analysis dividing the Mena(inv) surrogate by quartiles suggested collapse of the top three quartiles followed by comparison to the fourth quartile (log rank p= 0.0003, n=501). The 4th quartile was also significant in node positive (log rank p=0.0047, n=267) and estrogen negative (ER) patient subgroups (log rank p=0.0003, n=234). Cox multivariate analysis showed Mena(inv) was independent of age, tumor size, nuclear grade, nodal status, ER, PR, Her2 (HR=0.636, 95% CI=0.47-0.86, p=0.0038, n=420). The newer Yale cohort showed similar results, but that cohort also had data on local vs. distant recurrence. The relative risk of distant recurrence in this cohort is 2.56 (p=0.011) for patients with high Mena (inv) compared to 1.96 (p=0.055) for any recurrence.

Conclusions: High Mena (inv) surrogate shows prognostic value for poor survival in two independent breast cancer cohorts with some suggestion of preferential prognostic value for distant recurrence.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P3-10-16.

Subsistence economy of el paraiso, an early peruvian site

Studies of food remains from the Preceramic monumental site of E1 Paraíso, Peru (1800 to 1500 B.C.), have shed new light on a debate regarding the relative importance of seafood versus terrestrial resources and the role of cultigens in subsistence economies during the early development of Peruvian civilization. Fish was the primary animal food at the site whereas plant foods consisted of a mixture of cultivated resources (squashes, beans, peppers, and jicama) with an additional reliance on fruits (guava, lucuma, and pacae). Wild plants, especially the roots of sedges and cat-tail, also may have accounted for a substantial part of the diet. Cotton was a chief crop, used in making fishing tackle and the textiles that served as clothing and items of high value and status. As an example of the beginnings of civilization, El Paraíso is a case in which impressive architecture was built on a relatively simple subsistence economy and energy was expended in the production of resources useful in local and regional exchange systems.

High-frequency mutations in a plasmid-encoded gas vesicle gene in Halobacterium halobium

Gas vesicle-deficient mutants of Halobacterium halobium arise spontaneously at high frequency (about 1%). The mutants are readily detected, forming translucent colonies on agar plates in contrast to opaque wild-type colonies. To investigate the mechanism of this mutation, we recently cloned a plasmid-encoded gas vesicle protein gene, gvpA, from H. halobium. In the wild-type NRC-1 strain the gvpA gene is encoded by a multicopy plasmid of approximately 150 kilobase pairs (kb). We have now characterized 18 gas vesicle-deficient mutants and 4 revertants by phenotypic and Southern hybridization analyses. Our results indicate that the mutants fall into three major classes. Class I mutants are partially gas vesicle-deficient (Vac(delta-)) and unstable, giving rise to completely gas vesicle-deficient (Vac(-)) derivatives and Vac(+) revertants at frequencies of 1-5%. The restriction map of the gvpA gene region in class I mutants is unchanged but the gene copy number is reduced compared to the Vac(+) strains. Class II mutants can be either Vac(delta-) or completely Vac(-) but are relatively stable. They contain insertion sequences within or upstream of the gvpA gene. A Vac(-) class II mutant, R1, contains the 1.3-kb insertion sequence, ISH3, within the gvpA gene, whereas four Vac(delta-) class II mutants contain other insertion sequences upstream of the gene. Class III mutants are stable Vac(-) derivatives of either the wild-type or class I mutants and have no detectable copies of the gvpA gene. Based on these results, we discuss the mechanisms of gas vesicle mutations in H. halobium.

Ecophysiological Evidence that Achromatium oxaliferum Is Responsible for the Oxidation of Reduced Sulfur Species to Sulfate in a Freshwater Sediment

Achromatium oxaliferum is a large, morphologically conspicuous, sediment-dwelling bacterium. The organism has yet to be cultured in the laboratory, and very little is known about its physiology. The presence of intracellular inclusions of calcite and sulfur have given rise to speculation that the bacterium is involved in the carbon and sulfur cycles in the sediments where it is found. Depth profiles of oxygen concentration and A. oxaliferum cell numbers in a freshwater sediment revealed that the A. oxaliferum population spanned the oxic-anoxic boundary in the top 3 to 4 cm of sediments. Some of the A. oxaliferum cells resided at depths where no oxygen was detectable, suggesting that these cells may be capable of anaerobic metabolism. The distributions of solid-phase and dissolved inorganic sulfur species in the sediment revealed that A. oxaliferum was most abundant where sulfur cycling was most intense. The sediment was characterized by low concentrations of free sulfide. However, a comparison of sulfate reduction rates in sediment cores incubated with either oxic or anoxic overlying water indicated that the oxidative and reductive components of the sulfur cycle were tightly coupled in the A. oxaliferum-bearing sediment. A positive correlation between pore water sulfate concentration and A. oxaliferum numbers was observed in field data collected over an 18-month period, suggesting a possible link between A. oxaliferum numbers and the oxidation of reduced sulfur species to sulfate. The field data were supported by laboratory incubation experiments in which sodium molybdate-treated sediment cores were augmented with highly purified suspensions of A. oxaliferum cells. Under oxic conditions, rates of sulfate production in the presence of sodium molybdate were found to correlate strongly with the number of cells added to sediment cores, providing further evidence for a role for A. oxaliferum in the oxidation of reduced sulfur.

A simplified method for deriving shunt and reduced VA/Q in infants

BACKGROUND

Right to left shunt and regional hypoventilation (reduced ventilation/perfusion ratio (V(A)/Q)) have different effects on the curve relating inspired oxygen (P(I)O(2)) to oxygen saturation measured by pulse oximetry (SpO(2)) and can be derived non-invasively from measurements of SpO(2) and inspired oxygen pressure (P(I)O(2)) using complex models of gas exchange. We developed a simpler computerised "slide-rule" method of making these derivations.

AIMS

To describe the slide-rule method and determine agreement between measurements derived with this and a more complex algorithm.

METHODS

Series of P(I)O(2) versus SpO(2) data points obtained during 43 studies in 16 preterm infants with bronchopulmonary dysplasia were analysed. Percentage shunt and the degree of right shift (kPa) of the P(I)O(2) versus SpO(2) curve compared with the oxyhaemoglobin dissociation curve (a measure of V(A)/Q) were determined for each dataset with both methods, and the results were compared using the method of Bland and Altman.

RESULTS

The computer slide-rule method produced results for all 43 datasets. The more complex model could derive results for 40/43 datasets. The mean differences (95% limits of agreement) between the two methods for measurements of shunt were -1.7% (-6.5 to +3.5%) and for measurements of right shift were 0.3 kPa (-2.9 to +3.6 kPa).

CONCLUSION

The slide-rule method was reliable for deriving shunt and right shift (reduced V(A)/Q) of the P(I)O(2) versus SpO(2) curve when compared with the more complex algorithm. The new method should enable wider clinical application of these measurements of oxygen exchange.

Sources of hepatic triglyceride accumulation during high-fat feeding in the healthy rat

Hepatic triglyceride (HTG) accumulation from peripheral dietary sources and from endogenous de novo lipogenesis (DNL) was quantified in adult Sprague-Dawley rats by combining in vivo localized (1)H MRS measurement of total hepatic lipid with a novel ex vivo (2)H NMR analysis of HTG (2)H enrichment from (2)H-enriched body water. The methodology for DNL determination needs further validation against standard methodologies. To examine the effect of a high-fat diet on HTG concentrations and sources, animals (n = 5) were given high-fat chow for 35 days. HTG accumulation, measured by in vivo (1)H MRS, increased significantly after 1 week (3.85 +/- 0.60% vs 2.13 +/- 0.34% for animals fed on a standard chow diet, P < 0.05) and was maintained until week 5 (3.30 +/- 0.60% vs 1.12 +/- 0.30%, P < 0.05). Animals fed on a high-fat diet were glucose intolerant (13.3 +/- 1.3 vs 9.4 +/- 0.8 mM in animals fed on a standard chow diet, for 60 min glycemia after glucose challenge, P < 0.05). In control animals, DNL accounted for 10.9 +/- 1.0% of HTG, whereas in animals given the high-fat diet, the DNL contribution was significantly reduced to 1.0 +/- 0.2% (P < 0.01 relative to controls). In a separate study to determine the response of HTG to weaning from a high-fat diet, animals with raised HTG (3.33 +/- 0.51%) after 7 days of a high-fat diet reverted to basal HTG concentrations (0.76 +/- 0.06%) after an additional 7 days of weaning on a standard chow diet. These studies show that, in healthy rats, HTG concentrations are acutely influenced by dietary lipid concentrations. Although the DNL contribution to HTG content is suppressed by a high-fat diet in adult Sprague-Dawley rats, this effect is insufficient to prevent overall increases in HTG concentrations.

Tumor microenvironment of metastasis in human breast carcinoma: a potential prognostic marker linked to hematogenous dissemination

PURPOSE

Multiphoton-based intravital imaging has shown that invasive carcinoma cells in mouse and rat mammary tumors intravasate when associated with perivascular macrophages, identifying a potential tumor microenvironment of metastasis (TMEM). We define TMEM as the tripartite arrangement of an invasive carcinoma cell, a macrophage, and an endothelial cell. The aim of this study was to determine if TMEM density in human breast carcinoma samples predicts the development of systemic, hematogenous metastases.

EXPERIMENTAL DESIGN

A case-control study of 30 patients who developed metastatic breast cancer and 30 patients without metastatic disease was done. Cases were matched to controls based on currently used prognostic criteria. Paraffin-embedded primary breast cancer samples were stained using a triple immunohistochemical method allowing simultaneous identification of carcinoma cells, macrophages, and endothelial cells. Two pathologists, blinded to outcome, evaluated the number of TMEM per 20 high-power fields.

RESULTS

No association was seen between TMEM density and tumor size or grade, lymph node metastasis, lymphovascular invasion, or hormone receptor status. TMEM density was greater in the group of patients who developed systemic metastases compared with the patients with only localized breast cancer (median, 105 versus 50, respectively; P = 0.00006). For every 10-unit increase in TMEM density, the odds ratio for systemic metastasis was 1.9 (95% confidence interval, 1.1-3.4).

CONCLUSIONS

TMEM density predicted the development of systemic, hematogenous metastases. The ability of TMEM to predict distant metastasis was independent of lymph node status and other currently used prognosticators. Quantitation of TMEM may be a useful new prognostic marker for breast cancer patients.

Sources of endogenous glucose production in the Goto–Kakizaki diabetic rat

Plasma glucose, insulin and glucose tolerance were quantified in diabetic Goto-Kakizaki (GK) rats (342+/-45 g, n = 5) and compared with weight-matched non-diabetic Wistars (307+/-30 g, n = 8). Compared to Wistars, GK rats had higher fasting plasma insulin (219+/-50 versus 44+/-14 pmol/l, P<0.002) and glucose (9.2+/-2.3 versus 5.5+/-0.5 mmol/l, P<0.025). GK rats showed impaired glucose tolerance (IPGTT 2 h plasma glucose=14+/-1.5 versus 6.4+/-0.1 mmol/l, P<0.001). Endogenous glucose production (EGP) from glycogenolysis, phosphoenolpyruvate (PEP) and glycerol after 6 hours of fasting was quantified by a primed infusion of [U-(13)C]glucose and (2)H(2)O tracers and (2)H/(13)C NMR analysis of plasma glucose. EGP was higher in GK compared to Wistar rats (191+/-16 versus 104+/-27 mumol/kg per min, P<0.005). This was sustained by increased gluconeogenesis from PEP (85+/-12 versus 35+/-4 mumol/kg per min, P<0.02). Gluconeogenesis from glycerol was not different (20+/-3 in Wistar versus 30+/-6 mumol/kg per min for GK), and glycogenolysis fluxes were also not significantly different (76+/-23 mumol/kg per min for GK versus 52+/-19 mumol/kg per min for Wistar). The Cori cycle accounted for most of PEP gluconeogenesis in both Wistar and GK rats (85+/-15% and 77+/-10%, respectively). Therefore, increased gluconeogenesis in GK rats is largely sustained by increased Cori cycling while the maintenance of glycogenolysis indicates a failure in hepatic autoregulation of EGP.