Abstract P5-03-04: Effect of aging on the function and transformation of murine mammary stem cells

Epidemiological studies have shown that the risk of getting breast cancer progressively increases with age. A woman is 100 times more susceptible to develop breast cancer in her 60s than in her 20s. A better understanding of altered cellular and molecular mechanisms leading to the development of sporadic breast cancers as a result of aging are urgently needed for its prevention and treatment in growing population of older women. Recent research implicated that adult mammary stem cells (MaSCs) might be responsible for the initiation and progression of certain types of breast cancer. But no studies have been reported on how lifelong exposure of MaSCs to endogenous and environmental stresses during aging compromises their self-renewal and differentiation function and predispose them to neoplastic transformation either spontaneously or after carcinogen exposure. In our study, we have investigated the effect of progressive aging and carcinogen exposure on MaSC number and function in a murine model. The FACS isolated MaSC enriched basal cells, characterized by their immunophenotype (Lin−CD49fhighCD24med) were utilized to evaluate MaSC frequency and function during aging by in vitro mammosphere formation and 3D-ECM sphere differentiation assay as well as by in vivo cleared mammary fat pad transplantation (IVT). The results of our study showed that the percentage of MaSCs analyzed by both FACS profile and in vitro assays, increased steadily with increasing age observed at 2, 7, 17 and 25 month-old C57BL/6 mice. Subsequent IVT using mammosphers or 3D structures formed by young (4 months) and old MaSCs (28 months) derived from C57BL/6 mice showed similar in vivo functional mammary gland regenerative capacity indicating similar self-renewal/differentiation ability between young and old MaSCs. However, we found that the regenerated glands from old MaSCs had significantly higher number of spontaneous pre-neoplastic lesions (52.0%) than those from young MaSCs (18.3%). Significantly, MaSC frequency was also increased by the in vivo exposure of a carcinogen, N-Methyl-N-Nitrosourea (MNU, 25 mg/kg body weight, once a week for three consecutive weeks), in old mice with no effect on total mammary cell number. Furthermore, the old MaSCs expanded by MNU treatment were still capable of in vivo regeneration with similar success rate as that of normal old MaSCs. But, we observed increased frequency of hyperplasia and dysplasia in the regenerated glands initiated by MNU treated old MaSC. Our results indicate that MaSCs might be the precursors of preneoplastic lesions and old MaSCs appear to be predisposed to premalignant transformation, which is enhanced by the exposure to a DNA damaging agent.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P5-03-04.

Abstract P5-04-06: Soluble factors from activated immune cells induce epithelial mesenchymal transition in inflammatory breast cancer cells

Rationale: Inflammatory breast cancer (IBC) is the most insidious form of locally advanced disease. Emerging evidence suggests that host factors in the microenviromement may interact with underlying IBC genetics to promote the aggressive nature of the tumor. An integral part of the metastatic process involves epithelial to mesenchymal transition (EMT) where primary breast cancer cells gain motility and stem cell features that allow distant seeding. Interestingly, the IBC consortium microarray data found no clear evidence for EMT in IBC tumor tissues. However, it is unknown if soluble factors secreted by activated immune cells mediate EMT in the IBC microenvironment that may account for the absence of EMT in studies of the tumor cells themselves. Therefore, we tested whether the conditioned media of activated immune cells were capable of inducing EMT in IBC cells.

Methods: Conditioned media (CM) were generated using healthy donor peripheral blood mononuclear cells that were activated with anti-CD3 antibody immobilized to plastic and soluble anti-CD28 antibody to activate T cells through the T-cell receptor (TCR) or left unstimulated for 48 hours. Thereafter, CM from each of the cultures was harvested and filtered. Next, 48-hour pre-seeded SUM149 IBC cells were grown in culture medium consisting of 25% CM and 75% IBC culture medium for an additional 2 days. Unconditioned media and TGF-β were used as negative and positive controls, respectively for EMT. Following treatment with CM, RNA was extracted from the target cells and analyzed for the presence of EMT-related transcription factors (EMT-TF) and markers of epithelial and mesenchymal states by TaqMan® qRT-PCR. Subsequently, a panel of 24 genes was tested on 4 IBC cell lines (SUM149, SUM190, KPL4 and IBC-3) and 5 non-IBC cell lines (MCF-10a, MCF-7, MDA-231, and MDA-453) treated with immune-activated CM using the Fluidigm® Dynamic Array integrated fluidic circuit (“chip”) gene expression platform which allows for the simultaneous quantification of 2,304 data points using TaqMan® assays. Formalin-fixed, paraffin embedded blocks were prepared from trypsinized cells for immunohistochemical (IHC) staining to detect E-cadherin and vimentin expression.

Results: SUM149 cells cultured in the presence of TCR-activated CM for two days showed upregulation in EMT-TFs (SNAIL1, ZEB1, and TG2), vimentin and fibronectin by qRT-PCR. IHC staining showed increases in both vimentin and E-cadherin expression after 48-hour exposure to anti-TCR CM. Fluidigm® gene expression analysis of multiple cell lines exposed to anti-TCR CM showed that E-cadherin expression was unchanged or slightly decreased in non-IBC cell lines, whereas 3 of 4 IBC cell lines showed an increase in E-cadherin.

Discussion: These data suggest that soluble factors secreted by activated immune cells are capable of inducing EMT in IBC cells and may mediate the persistent E-cadherin expression observed in IBC. Such processes may contribute to the highly aggressive nature of the disease; however, an immune competent in vivo model is warranted to fully understand the implications of these findings.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P5-04-06.

Abstract P2-03-01: Identification of cancer stem cells (CD44+CD24−/lo) in bone marrow as a prognostic factor in early breast cancer patients

Background: Cancer stem cells (CSCs) in bone marrow (BM) are epithelial tumor cells that express CD44+CD24−/lo. CSCs can be further divided into those that have ALDH activity (Aldefluor+) and those that do not. We hypothesized that if CSCs are responsible for tumor dissemination, their presence in BM would be prognostic in early stages of breast cancer (EBC) patients. Therefore, using multiparameter flow cytometry (FACS), we assessed epithelial cells for expression of CD44+CD24−/low and Aldefluor in BM of EBC patients and correlated these findings with circulating tumor cells (CTC), disseminated tumor cells (DTC) and clinical outcome.

Methods: This is a prospective laboratory study (Protocol 04–0657) conducted in the Departments of Surgical Oncology and Hematopathology, at The University of Texas MD Anderson Cancer Center in Houston, TX, USA, and was approved by the institutional review board. BM aspirates were collected at the time of surgery from 108 patients with EBC. BM was analyzed for CSCs and ALDH activity by FACS analysis. Ten cytospin slides of the bone marrow mononuclear cells were prepared from each BM aspirate and reacted with a cocktail of antibodies, including AE1/AE3, CAM5.2, MNF116, CK8 and CK18, to identify epithelial cells (DTC) by immunohistochemistry (IHC). In addition, the CellSearch system (Veridex, Raritan, NJ) was used to enumerate CTCs in each of 3 tubes of 7.5 mL of peripheral blood per patient. Overall survival (OS) and disease-free survival (DFS) were calculated from the date of diagnosis and analyzed with Kaplan-Meier survival plots. Cox multivariate proportional hazards model was also performed.

Results: Of the 103 evaluable patients, 45 patients received neoadjuvant chemotherapy, 35 adjuvant chemotherapy and 23 no chemotherapy. The median follow-up was 40 months (range 7–66 months). Patients with CSCs in BM had a hazard ratio (HR) of 8.8 for DFS (p = 0.002); patients with Aldefluor+ CSCs had a HR of 5.9 (p = 0.052) for DFS. Seven patients have expired and all of them had CSCs in BM. Moreover, we evaluated the presence of DTCs by FACS (CD326+CD45−) in 104 patients. Sixty-one (75%) of patients had positive BM samples for DTC (CD326+CD45- BM cells ≥ 0.53%). No association was shown between DTC in BM as determined by FACS and CTCs in PB. In a multivariate model, after adjusting for age (< 45 years old), clinical T stage, N stage, ER, PR, HER2 status, and nuclear grading, the presence of CSCs was found to be an independent predictor of DFS (HR = 15.8, P = 0.017) as was the presence of CTCs (HR = 13.9, P = 0.007). In this subset of patients, the presence of Aldefluor+ CSCs and DTCs was not found to be predictive of DFS in the multivariate model including the same factors as listed above.

Conclusions: Our data indicate that the presence of BM metastasis is correlated to CSCs, and CSCs irrespective of ALDH activity are independent adverse prognostic factors in EBC patients. Moreover, the presence of CTCs was a strong independent predictor of DFS.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P2-03-01.

[Growth inhibition of transfection of p16 gene to lung adenocarcinoma cell lines Anip973 and AGZY83-a]

BACKGROUND

To investigate the suppression effect of tumor suppressor gene p16 on lung adenocarcinoma cell lines.

METHODS

p16 expression vector was transfected into high metastasis lung carcinoma cell line, Anip973, and low metastasis lung cancer cell line, AGZY83-a. The suppression effects of p16 gene on cell growth was detected by cell growth curve, cloning efficiency assay, flow cytometry analysis and TUNEL technique.

RESULTS

Overexpression of p16 gene in Anip973 and AGZY83-a could only lead the cells to arrest at G1 phase, but had no effects on cell growth curves, colony for mation rate and apoptosis.

CONCLUSIONS

Overexpression of p16 in Anip973 and AGZY83-a can not suppress the growth of the tumor cells.

[High dose chemotherapy combined with peripheral blood stem cell transplantation (PBSCT) in the treatment of patients with small cell lung cancer]

BACKGROUND

To investigate the therapeutic effect and safety of PBSCT combined with high dose chemotherapy in the treatment of small cell lung cancer(SCLC).

METHODS

From March, 1994 to June, 1999, high dose chemotherapy combined with PBSCT was carried out in 20 patients with SCLC. Eight patients were in CR status while twelve patients were for salvaging therapy. Allo-PBSCT was performed in 1 patient and Auto-PBSCT in 19 patients. After mobilization of stem cell, mononeuclear cell (MNC) was collected for ≥3.0×10⁸/kg, CD34+ cell≥2.0×10⁶/kg. The high dose chemotherapy included carboplatin 350 mg/m²×3 days, VP-16 120 mg/m²×5 days, and E-ADM 40 mg/m²×2 days.

RESULTS

Encouraging results were achieved in 8 patients who were in CR status. Seven of the eight patients survived after Auto-PBSCT. One patients survived more than 1 year, 4 cases over 2 years, and 3 cases over 3 years. Of the 3 patients, 2 survived more than 4 years. In the group of salvaging therapy, response was good, however there was no long-term survival and median remission time was only 3.5 months.

CONCLUSIONS

High dose chemotherapy combined with PBSCT in the treatment of SCLC with CR status is feasible and safe, although the side effects are severe too. It is worth further studying on clinical practice.

LV wall segmentation using the variational level set method (LSM) with additional shape constraint for oedema quantification

In this paper an automatic algorithm for the left ventricle (LV) wall segmentation and oedema quantification from T2-weighted cardiac magnetic resonance (CMR) images is presented. The extent of myocardial oedema delineates the ischaemic area-at-risk (AAR) after myocardial infarction (MI). Since AAR can be used to estimate the amount of salvageable myocardial post-MI, oedema imaging has potential clinical utility in the management of acute MI patients. This paper presents a new scheme based on the variational level set method (LSM) with additional shape constraint for the segmentation of T2-weighted CMR image. In our approach, shape information of the myocardial wall is utilized to introduce a shape feature of the myocardial wall into the variational level set formulation. The performance of the method is tested using real CMR images (12 patients) and the results of the automatic system are compared to manual segmentation. The mean perpendicular distances between the automatic and manual LV wall boundaries are in the range of 1-2 mm. Bland-Altman analysis on LV wall area indicates there is no consistent bias as a function of LV wall area, with a mean bias of -121 mm(2) between individual investigator one (IV1) and LSM, and -122 mm(2) between individual investigator two (IV2) and LSM when compared to two investigators. Furthermore, the oedema quantification demonstrates good correlation when compared to an expert with an average error of 9.3% for 69 slices of short axis CMR image from 12 patients.

Induction of autophagy and senescence by knockdown of ROC1 E3 ubiquitin ligase to suppress the growth of liver cancer cells

Regulator of Cullins-1 (ROC1) or RING box protein-1 (RBX1) is an essential RING component of Cullin-RING ligase (CRL). Our previous studies showed that ROC1 is required for the growth of several cancer cell lines while ROC1 siRNA silencing inactivates CRL, leading to cell cycle arrest, cell senescence and/or apoptosis. However, it is completely unknown whether ROC1 knockdown triggers autophagic response by inactivating CRL. Moreover, the role of ROC1 in liver cancer remains elusive. In this study, we reported that ROC1 knockdown significantly inhibited the growth of liver cancer cells by sequentially and independently inducing autophagy and p21-dependent cell senescence. Mechanism analysis revealed that ROC1 silencing triggered autophagy by inhibition of mammalian target of rapamycin (mTOR) activity due to accumulation of mTOR-inhibitory protein Deptor, a substrate of CRL. Consistently, Deptor knockdown significantly blocked autophagy response upon ROC1 silencing. Biologically, autophagy response upon ROC1 silencing was a survival signal, and blockage of autophagy pathway sensitized cancer cells to apoptosis. Finally, we demonstrated that ROC1 was overexpressed in hepatocellular carcinomas, which is associated with poor prognosis of liver cancer patients. These findings suggest that ROC1 is an appealing drug target for liver cancer and provide a proof-of-concept evidence for a novel drug combination of ROC1 inhibitor and an autophagy inhibitor for effective treatment of liver cancer by enhancing apoptosis.

DJ-1 protects dopaminergic neurons against rotenone-induced apoptosis by enhancing ERK-dependent mitophagy

Loss-of-function mutations in the gene encoding the multifunctional protein, DJ-1, have been implicated in the pathogenesis of early-onset familial Parkinson's disease (PD), suggesting that DJ-1 may act as a neuroprotectant for dopaminergic (DA) neurons. Enhanced autophagy may benefit PD by clearing damaged organelles and protein aggregates; thus, we determined if DJ-1 protects DA neurons against mitochondrial dysfunction and oxidative stress through an autophagic pathway. Cultured DA cells (MN9D) overexpressing DJ-1 were treated with the mitochondrial complex I inhibitor, rotenone. In addition, rotenone was injected into the left substantia nigra of rats 4weeks after injection with a DJ-1 expression vector. Overexpression of DJ-1 protected MN9D cells against apoptosis, significantly enhanced the survival of nigral DA neurons after rotenone treatment in vivo, and rescued rat behavioral abnormalities. Overexpression of DJ-1 enhanced rotenone-evoked expression of the autophagic markers, beclin-1 and LC3II, while transmission electron microscopy and confocal imaging revealed that the ultrastructural signs of autophagy were increased by DJ-1. The neuroprotective effects of DJ-1 were blocked by phosphoinositol 3-kinase and the autophagy inhibitor, 3-methyladenine, and by the ERK pathway inhibitor, U0126. Confocal imaging revealed that the size of p62-positive puncta decreased significantly in DJ-1 overexpression of MN9D cells 12h after rotenone treatment, suggesting that DJ-1 reveals the ability to clear aggregated p62 associated with PD. Factors that control autophagy, including DJ-1, may inhibit rotenone-induced apoptosis and present novel targets for therapeutic intervention in PD.

Thermal activation in atomic friction: revisiting the theoretical analysis

The effect of thermal activation on atomic-scale friction is often described in the framework of the Prandtl-Tomlinson model. Accurate use of this model relies on parameters that describe the shape of the corrugation potential β and the transition attempt frequency f(0). We show that the commonly used form of β for a sinusoidal corrugation potential can lead to underestimation of friction, and that the attempt frequency is not, as is usually assumed, a constant value, but rather varies as the energy landscape evolves. We partially resolve these issues by demonstrating that numerical results can be captured by a model with a fitted β and using harmonic transition state theory to develop a variable form of the attempt frequency. We incorporate these developments into a more accurate and generally applicable expression relating friction to temperature and velocity. Finally, by using a master equation approach, we verify the improved analytical model is accurate in its expected regime of validity.

Determination of norcantharidin in mouse tissues by liquid chromatography coupled to tandem mass spectrometry and its tissue distribution study

The purpose of this study is to determine the concentrations of norcantharidin (CAS NO: 5442-12-6) in mouse tissues and investigate its tissue distribution after intragastric administration of disodium norcantharidate solution. A highly sensitive and specific liquid chromatography-tandem mass spectrometric (LC-MS/MS) method was developed and validated, using ribavirin (CAS NO: 36791-04-5) as the internal standard (IS). Norcantharidin and IS were extracted from 0.3 mL tissue homogenates using protein precipitation with acetone under acid condition. The analyte was separated on a C18 reverse phase column and analyzed by MS/MS in the multiple reaction monitoring (MRM) mode using ESI with positive ionization, m/z 169→123 for norcantharidin and m/z 267→135 for IS. The developed method was validated over a linear range of concentrations 0.01~5 μg·mL - 1 in liver, lung, kidney, stomach, small intestine, uterus and testis, 0.005~0.5 μg·mL - 1 in heart, spleen and brain, the correlation coefficients (r2) were between 0.9918 and 0.9976. The tissue distribution study result was as follows: The AUC0-t of norcantharidin in tissues was in the order as follows: small intestine, stomach, uterus, kidney, testis, liver, lung, spleen, heart, brain.

Pharmacokinetic and bioequivalence studies of trospium chloride after a single-dose administration in healthy Chinese volunteers

The study aimed to compare and evaluate the bioequivalence of a new generic preparation of trospium chloride (CAS NO:10405-02-4) capsule (20 mg, test) and the available import tablet (20 mg , reference) for the requirement of state regulatory criteria in China. A randomized- sequence, 2-period crossover study was conducted in 20 healthy Chinese male volunteers in the fasted state. Blood samples were collected before and 1, 2, 3, 4, 5, 6, 7, 8, 12, 24, 36, 48, 60 h after administration of a single oral dose of 40 mg trospium chloride capsules or tablets, followed by a 7-day washout period. The concentration of trospium chloride was determined by a LC-MS/MS method. Drug And Statistical-Version 2.0 was used to calculate the pharmacokinetics parameters and assess bioequivalence of the two preparations. It was considered bioequivalent if the 90% CIs of the mean ratios (test: reference) for Cmax, AUC0-t and AUC0-∞ were within the range from 80% to 125%, respectively. The main pharmacokinetics parameters of test and reference were as follows: t1/2 was (15.11 ± 3.24) h and (16.00 ± 3.96) h; Tmax was (4.0 ± 1.2) h and (4.1 ± 0.9) h; Cmax was (3.76 ± 1.87) ng·mL - 1 and (3.70 ± 1.89) ng·mL - 1; AUC0-t was (33.51 ± 14.39) ng·mL - 1·h and (33.33 ± 14.88) ng·mL - 1·h, and the AUC0-∞ was (35.20 ± 14.88) ng·mL - 1·h and (35.16±15.17) ng·mL - 1·h. The ratios (test: reference) for Cmax, AUC0-t, and AUC0-∞ were 94.0%~111.7%, 96.4%~106.8%, and 96.1%~105.3%, respectively. No significant differences in pharmacokinetic parameters were found between preparations and periods (p>0.05). No obvious adverse events were monitored throughout the study based on clinical parameters and patient reports.

Beam-target double-spin asymmetry A{LT} in charged pion production from deep inelastic scattering on a transversely polarized {3}He target at 1.4<Q{2}<2.7 GeV{2}

We report the first measurement of the double-spin asymmetry A{LT} for charged pion electroproduction in semi-inclusive deep-inelastic electron scattering on a transversely polarized {3}He target. The kinematics focused on the valence quark region, 0.16<x<0.35 with 1.4<Q{2}<2.7  GeV{2}. The corresponding neutron A{LT} asymmetries were extracted from the measured {3}He asymmetries and proton over {3}He cross section ratios using the effective polarization approximation. These new data probe the transverse momentum dependent parton distribution function g{1T}{q} and therefore provide access to quark spin-orbit correlations. Our results indicate a positive azimuthal asymmetry for π{-} production on {3}He and the neutron, while our π{+} asymmetries are consistent with zero.

CMRI based 3D left ventricle motion analysis on patients with acute myocardial infarction

3D Quantitative measurement of left ventricle (LV) motion on patients with acute myocardial infarction has been recognized as essential for effective LV function diagnosis. This paper presents a method to quantify 3D LV motion obtained from conventional CINE MRI using image analysis based on mathematical modeling. Level set method is employed for segmentation, and a 3D LV geometry was reconstructed by co-registering different views of MRI images. A mathematical model of LV geometry was then constructed to quantitatively describe the LV wall inward motion. The results using real data show that the method is able to quantify the LV inward motion, and can clearly represent the changed motion pattern with the follow-up data. Furthermore, the LV motion analysis for 8 patients with acute myocardial infarction (MI) show that high inward motion occurs mainly in the basal region of LV while a negative relation is found between LV ejection fraction (EF) improvement after acute MI and solely basal region inward motion, which could be helpful for diagnosis and LV EF recovery prediction.

Precise measurement of deuteron tensor analyzing powers with BLAST

We report a precision measurement of the deuteron tensor analyzing powers T(20) and T(21) at the MIT-Bates Linear Accelerator Center. Data were collected simultaneously over a momentum transfer range Q=2.15-4.50 fm(-1) with the Bates Large Acceptance Spectrometer Toroid using a highly polarized deuterium internal gas target. The data are in excellent agreement with calculations in a framework of effective field theory. The deuteron charge monopole and quadrupole form factors G(C) and G(Q) were separated with improved precision, and the location of the first node of G(C) was confirmed at Q=4.19±0.05 fm(-1). The new data provide a strong constraint on theoretical models in a momentum transfer range covering the minimum of T(20) and the first node of G(C).

P4-20-04: Cytokine Synthesis by Activated Dendritic Cells in Relation to Disease Progression in Inflammatory Breast Cancer (IBC)

Background: Deficiencies in innate and adaptive immune responses by plasmacytoid dendritic cells (pDC) and myeloid DC (mDC) have been linked to poor clinical outcome in breast cancer (BC) (Treilleux, Clin Cancer Res, 2004, PMID 15569976). pDC produce IFN-a and pro-inflammatory cytokines that regulate innate and adaptive immunity in breast cancer. mDC present in blood and secondary lymphoid organs secrete IL-12 and induce inflammatory cytokine production by T cells. Therefore, we studied DC activity in the peripheral blood and assessed their function with clinical outcome in breast cancer patients.

Methods: We recruited 115 BC patients [25 with locally advanced non-IBC (LABC), 25 with IBC, 21 with metastatic breast cancer (MBC), and 44 with metastatic IBC (mIBC)] and 31 healthy donors (HD) for this study. Peripheral blood pDC and mDC were activated through toll-like receptor (TLR)-7 to assess IFN-α and IL-10 production whereas mDC were activated through TLR-8 to assess production of IL-12 and TNF-α by multi-parameter flow cytometry. Associations between cytokine production by TLR-activated pDC and mDC with progression free survival (PFS) and overall survival (OS) of patients were analyzed by Kaplan Meier Test.

Results: The median follow-up (FU) of 113 evaluable patients was 14.1 months with a median time to progression of 10.5 months; 54 patients had stable disease (SD) and 59 had progression of disease (PD). Metastasis, previous treatments, and IBC contributed to shorter PFS and OS. Compared to HD, BC patients had significantly fewer total DC (p=0.008), mDC (p=0.008), and pDC (p=0.003) per μL. In general, the number of TLR-7-activated pDC per μL that produced IFN-a(p=0.023) or IL-10 (p=0.027) and the number of TLR-8-activated mDC per μL that produced IL-12 (p&lt;0.001) or TNF-α (p=0,008) were significantly lower in BC patients than in HD. However, patients with DC that produced these cytokines above the median levels of HD had shorter PFS or OS. In IBC patients, higher numbers of TLR-8-activated mDC that produced TNF-α (p=0.025) or IL-12 (p=0.003) predicted shorter OS. In mIBC patients, a higher number of TLR-7-activated pDC producing IFN-α (p=0.024) or IL-10 (p=0.034) predicted shorter PFS.

Conclusion: BC patients had significantly fewer pDC and mDC in peripheral blood than HD. IBC patients with above average numbers of TLR-activated DC capable of producing proinflammatory cytokines had a significantly shorter PFS or OS. Disease progression in IBC is related to an increased number of activated dendritic cells producing inflammatory cytokines.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-20-04.

P1-02-07: Epithelial-Mesenchymal Transition Correlated with Serum Cytokine Profiling in Breast Cancer Patients

Background: Inflammation contributes to the increased invasiveness and poor prognosis in breast cancer (BC) patients. Specifically, the expression of the proinflammatory cytokines interleukin-6 (IL-6), tumor necrosis factor alpha (TNFα) and interleukin-1 (IL-1) have all been linked to increased invasiveness and poor prognosis. Interestingly, the increased invasiveness was associated with an increase in the acquisition of markers of epithelial-mesenchymal transition (EMT). Therefore, we determined whether the levels of circulating proinflammatory cytokines (IL-1, IL-6, TNFα) and antiinflammatory cytokines (IL10) were correlated with the induction of EMT transcription factors (TFs), Snail1, Zeb1, Twist1, in breast cancer patients.

Materials and Methods: From two laboratory-based ongoing studies at the MD Anderson Cancer Center, 41 BC patients were assessed for EMT-TFs in circulating CD45-ve cells (EMT-CTCs) and for serum proinflammatory cytokines before starting any treatment. 32 of 41 patients assessed for EMT had metastatic BC. EMT-CTCs were detected by qRT-PCR for the EMT-TFs Snail1, Zeb1 and Twist1 (Mego 2011; PMID 21387303) and serum cytokines were measured by Luminex bead array assay (MILLIPLEX™ MAP Human Cytokine/Chemokine Panel). Cytokine serum concentrations were compared with the median cytokine levels of healthy donors (HD). We examined the association of serum cytokines above the median HD levels and the presence of EMT-CTCs by non-parametric Mann-Whitney test with a statistical significance for p&lt;.05.

Results: Of the 41 patients assessed for both serum cytokines and EMT-CTCs, 14 (34%) were positive for at least one EMT-TF, including 3 of 9 (33%) patients with no-metastatic BC and 11 of 32 (34%) patients with metastatic BC. We found that serum levels of IL1a, IL2, TGFα, and TNFβ in patients that were above the median levels of HD sera were higher in patients with EMT-CTCs in the blood (higher IL1a concentration in patients with over expression of Snail1, Zeb1, and Twist1; IL2 with Zeb1; TGFα with Snail1; TNFβ with Zeb1, and Twist1). Further, the higher ratio of proinflammatory/anti-inflammatory cytokines, was associated with the presence of at least one EMT-TF, e.g., IL8/IL10 (p=.005) and TNFα/IL10 (p=.037). Discussion: Patients with proinflammatory cytokine (IL1a, IL2, TGFα, and TNFβ) levels above the median levels of HD or who had a predominantly proinflammatory cytokine profile were more likely to have at least one EMT-TF in their blood. These data are consistent with the hypothesis that proinflammatory cytokines promote EMT, which may be involved in tumor aggressiveness and disease progression.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-02-07.

P1-04-02: In Vitro Qualification and Quantification of Murine Mammary Stem/Progenitor Cells

Increasing evidence suggest that tumors with a cell origin of more basal or stem-like sources are often highly metastatic and associated with poor prognosis. Identification of the cell of origin thus has important implications for development of new preventive and therapeutic approaches. To identifying the cells of origin of various breast cancers, understanding the normal cellular hierarchy within the breast tissue is an important prerequisite. However, current understanding of normal mammary stem/progenitor cell is limited due to the lack of a robust in vitro assay. The newly developed cell surface markers (CD24+CD49fhi) can only be used for low percent of enrichment. The only gold standard assay for functional evaluation of stem cell property is the in vivo transplantation of cleared mammary fat pad assay, yet this assay is expensive, time consuming, and requires highly trained skills, and thus cannot be used routinely for experiments. The goal of our study is thus to develop a robust in vitro assay to qualify and quantify murine mammary stem/progenitor cells. Our rationale lies on our recent findings of in vitro study of different fractions of murine stem/progenitor cells. When we use isolated primary epithelial cells for in vitro mammosphere formation, we found that stem cell enriched fraction and progenitor cell enriched fraction both formed very small mammospheres (≤ 50 μm) and these spheres appear to be of clonal origin (one cell gives rise to one sphere). When we plated these small spheres into 3D extracellular matrix for colony formation, however, they gave rise to two distinct structures: stem-enriched fraction generated predominately solid structure while progenitor-enriched fraction is dominated by hollow structures. Previous studies have linked the solid structure to the basal/myoepithelial lineage and the hollow structure to the luminal lineage. We thus suspected that the small mammospheres derived from the stem or progenitor enriched fractions could be originated from single stem or progenitor cell, and the number of spheres could indicate the number of original stem/progenitor cells within these enriched fractions. Subsequent in vivo transplantation with single sphere or single solid structure cultured in 3D extracellular matrix derived from green fluorescent protein transgenic mice proved that single sphere or 3D solid structure can repopulate the gland-free mammary fat pad. To conclude, the in vitro mammosphere formation in combination with subsequent differentiation in 3D extracellular matrix can be used as a robust in vitro assay for qualification and quantification of murine mammary stem/progenitor cells. This in vitro assay will greatly facilitate our understanding of genes regulate stem cell self-renewal, proliferation, differentiation as well as mechanisms keeping them at quiescent state within the niche.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-04-02.

P3-03-02: Higher Expression Levels of Circulating miR-21, miR-19a and miR-10b Are Associated with High Risk Features in Breast Cancer

Background: MicroRNAs (miRs) have oncogenic and tumor-suppressor functions. MiR-21, miR-19a and miR-10b are overexpressed in breast cancer and regulate tumor cell migration, invasion and angiogenesis. We assessed the levels of miR-21, -19a, and -10b in sera of breast cancer patients and their association with the stage, histological type, hormonal receptor (HR) status and HER2 amplification in the primary tumor. Since circulating tumor cells (CTC) detected by CellSearch® are an independent and strong predictor of overall survival in metastatic breast cancer (MBC), we assessed the relationship between circulating miRs and CTCs.

Methods: The study consisted of 30 healthy donors (HD) and 95 breast cancer (BC) patients. Patients’ sera were collected before starting a new line of treatment. Total RNA was isolated, reverse transcribed to cDNA and then subjected to qRT-PCR for the detection of miR-21, -19a, -10b and -192 using the TaqMan MicroRNA Assay (Applied Biosystems, Foster City, CA). Mir-192 was used to normalize the expression levels of the other miRs. Fold-changes in expression of miRs were calculated using the 2−DCt method, where DCt= mean CTtarget-miRNA -mean CTmiR-192. CTCs were enumerated using CellSearch™ (Veridex LLC, Warren, NJ). Mann-Whitney U test was used to determine differences in serum miR expression levels between patients and HD.

Results: Of the 95 BC patients, 39 were non-MBC and 56 MBC. Patients grouped according to the receptor expression by immunohistochemical staining consisted of 27 HR+HER2−, 30 HR+HER2+, 20 HRHER2+, and 18 HRHER2− triple negative BC (TNBC). MiR-21 and miR-19a were higher in non-MBC patients than in HD (p=.001, p&lt;.001, respectively). MiR-21, miR-19a and miR-10b levels were higher in metastatic patients than in HD (p&lt;.001, p&lt;.001, p=.038, respectively). MBC patients had a higher median level of miR-21 than that of non-MBC patients (p=.02). Patients with (HR+HER2+, HR−HER2+, TNBC) had significantly higher median levels of both miR-21 (p=.018; p=.009; p=.045) and miR-10b (p=.011; p=.014; p=.03) compared with HR+HER2− BC. HER2+ patients had higher median levels of both miR-21 and miR-10b than those of HER2− BC (p=.033; p=.01) and HD (p&lt;.001; p=.009). Further, median miR-19a expression was higher in IBC patients than in non-IBC patients (p=.025). Finally, patients with &lt;5 CTCs had a higher median expression level of miR-10b than that of patients with ≥5 CTCs (p=.042).

Discussion: High expression levels of miR-21, miR-19a and miR-10b in sera are observed in breast cancer patients, especially with advanced disease. HER2+ BC patients had higher serum levels of miR-21 and miR-10b than HER2−. IBC patients had a higher serum level of miR-19a than non-IBC patients. Moreover, patients with &lt;5 CTCs had high serum levels of miR-10b that can be induced by Twist1 during the epithelial-mesenchymal transition (EMT) and, in part, explain the inability of CellSearch® to detect CTCs undergoing EMT.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-03-02.

P4-20-03: T-Cell Cytokine Production Related to Progression of Breast Cancer Patients

Background: Impaired immunosurveillance and immune dysregulation contribute to the pathogenesis and progression of breast cancer (BC). Upon activation, T cells synthesize inflammatory cytokines such as TNF-α that can promote or inhibit tumor growth. We therefore investigated T-cell cytokine syntheses as a predictor of disease progression.

Methods: We recruited 115 BC patients [25 with locally advanced breast cancer (LABC), 21 with metastatic breast cancer (MBC), 25 with non-metastatic inflammatory breast cancer (IBC), and 44 with metastatic IBC (mIBC)] and 31 healthy donors (HD) for this ongoing study. The tumor phenotype consisted of 69 hormone receptor (HR) positive (including 26 patients with HER2 positive disease), 16 HR negative but HER2+, 30 triple negative BC (TNBC). To evaluate T cell function, peripheral blood mononuclear cells from patients and HD were stimulated overnight with immobilized anti-CD3 and soluble anti-CD28 antibodies and assessed for the percentage of T cells that synthesized cytokines by multi-parameter flow cytometry. The associations of T cell cytokine production profile with patient progression free survival (PFS) were analyzed by Kaplan Meier Test.

Results: The median follow-up (FU) of 113 evaluable patients was 14.1 months with a median time to relapse of 10.5 months; 54 patients had stable disease (SD) and 59 patients had progression of disease (PD). In the entire cohort, on univariate analysis, metastasis, IBC, stage, and previous treatment predicted for worse PFS (p&lt; 0.05). In non-metastatic patients (LABC+IBC), absolute count of anti-CD3 activated CD8+ T cells producing IL-17 was significantly higher in the SD patients compared with patient with PD (p=0.038), but it did not predict PFS (p=0.073). Similarly in metastatic patients, anti-CD3 activated CD4+ T cells producing TNF-α were significantly higher in patients with SD (p=0.025) and was predictive of longer PFS (p=0.033). Considering all patients with IBC (IBC + mIBC), although patients with PD had significantly fewer (percent and absolute number) anti-CD3 activated T cells capable of producing cytokines, this immune impairment was mostly related to metastasis and previous treatment. However, the percentage of anti-CD3 activated CD8+ T cells producing TNF-α was an independent positive prognostic indicator of PFS (p=0.002).

Conclusion: Higher than average cytokine syntheses by anti-CD3 activated T cells are significantly associated with longer PFS. These data are consistent with the hypothesis that an adaptive immune response can control disease progression.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P4-20-03.

Heading date gene, dth3 controlled late flowering in O. Glaberrima Steud. by down-regulating Ehd1

Heading date in rice is an important agronomic trait controlled by several genes. In this study, flowering time of variety Dianjingyou 1 (DJY1) was earlier than a near-isogenic line (named NIL) carried chromosome segment from African rice on chromosome 3S, when grown in both long-day (LD) and short-day (SD) conditions. By analyzing a large F2 population from NIL × DJY1, the locus DTH3 (QTL for days to heading on chromosome 3) controlling early heading date in DJY1 was fine mapped to a 64-kb segment which contained only one annotated gene, a MIKC-type MADS-box protein. We detected a 6-bp deletion and a single base substitution in the C-domain by sequencing DTH3 in DJY1 compared with dth3 in NIL, and overexpression of DTH3 caused early flowering in callus. Quantitative real-time PCR revealed that the transcript level of dth3 in NIL was lower than that DTH3 in DJY1 in both LD and SD conditions. The Early heading date 1 (Ehd1) which promotes the RFT1, was up-regulated by DTH3 in both LD and SD conditions. Based on Indel and dCAPs marker analysis, the dth3 allele was only present in African rice accessions. A phylogenetic analysis based on microsatellite genotyping suggested that African rice had a close genetic relationship to O. rufipogon and O. latifolia, and was similar to japonica cultivars. DTH3 affected flowering time and had no significant effect on the main agronomic traits.