Reprogramming of the tumour microenvironment by stromal PTEN-regulated miR-320

Phosphatase and tensin homolog deleted on chromosome ten (Pten) in stromal fibroblasts suppresses epithelial mammary tumors, but the underlying molecular mechanisms remain unknown. Using proteomic and expression profiling, we show that Pten loss from mammary stromal fibroblasts activates an oncogenic secretome that orchestrates the transcriptional reprogramming of other cell types in the microenvironment. Downregulation of miR-320 and upregulation of one of its direct targets, ETS2, are critical events in Pten-deleted stromal fibroblasts responsible for inducing this oncogenic secretome, which in turn promotes tumor angiogenesis and tumor cell invasion. Expression of the Pten-miR-320-Ets2 regulated secretome distinguished human normal breast stroma from tumor stroma and robustly correlated with recurrence in breast cancer patients. This work reveals miR-320 as a critical component of the Pten tumor suppressor axis that acts in stromal fibroblasts to reprogram the tumor microenvironment and curtail tumor progression.

P3-17-02: Targeting the Autophagy Pathway for Drug Resistance of Breast Tumor-Initiating Cells

Background: Our clinical data and experimental evidence reveal that the tumor-initiating cells (TICs) in the original tumor are intrinsically resistant to conventional chemotherapy and radiation therapy and greatly enriched in residual breast cancers after such treatments. We have published a gene expression signature of such breast TICs, and our pathway analysis on the gene signature suggests that the activation of autophagy pathway may be an intrinsic characteristic of the TICs. This motivates us to further investigate the role of the autophagy pathway in TICs self-maintenance and their resistance to hormonal and chemo therapies, as well as their response to TIC-targeted therapies.

Methods: A collective 84 well-documented autophagy pathway genes were used to compare the activation of autophagy pathway in different microarray datasets, 1) flow-sorted CD44+/CD24−/low cancer cells vs. all other cells (representing 20 patients), and cancer-derived MSs vs. corresponding primary bulk tumors (representing 17 patients), 2) before vs. after letrozole and doxetaxel treatments (representing 30 patient pairs), 3) before vs. after letrozole treatment (representing 176 patient pairs), and 4) before vs. after lapatinib treatment (representing 115 patient pairs). We applied the Significance Analysis of Microarrays (SAM) algorithm to analyze the expression data of 211 normalized probes for the 84 genes. Low-density RTPCR array for the 84 genes was used to confirm the differential expressed genes on tumor tissues of 18 letrozol treated patient pairs. Two human-cancer-in-mouse triple-negative xenograft tumor lines were treated with Notch pathway inhibitor alone or in combining with docetaxel. The tumor growth, mammosphere formation efficiency, and the expression of autophagy marker proteins were evaluated.

Results: Overall, the enrichment analysis of the 84-gene set in all the above microarray datasets showed that the autophagy genes are significantly enriched in the differential expressed genes. In particular, 28 out of the 84 autophagy genes are significantly up-regulated in the TICs populations while 5 other autophagy genes are down-regulated with the false discovery rate (FDR) less than 0.05. For the letrozole and doxetaxel treatment microarray analysis, 34 out of the 84 autophagy genes are significantly up-regulated in the after-treatment group (p<0.01), and only 3 out of the 84 autophagy genes are down-regulated (FDR<0.05). Interestingly, significantly more autophagy genes (15 out of the 84) are down-regulated in the after-lapatinib treatment group (p<0.05), and less genes (13 out of 84) are up-regulated after lapatinib treatment, thus confirming previous observations that lapatinib may affect TICs. We confirmed these findings in two human cancer xenograft studies of Notch pathway inhibitor (GSI) to target TICs, which showed significantly reduced expressions of LC3 and p62, two autophagic markers. In both xenograft models, GSI reduced mammosphere formation efficiency compared to vehicle control (p<0.05).

Conclusion: Activation of the autophagy pathway in TICs is a promising target to combat the drug resistance of breast cancer to conventional systemic therapy.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P3-17-02.

All-optical wavelength conversion for 10 Gb/s DPSK signals in a silicon ring resonator

We demonstrate all-optical wavelength conversion at 10 Gb/s for differential phase-shift keyed (DPSK) data signals in the C-band, based on four-wave mixing (FWM) in a silicon ring resonator. Error-free operation with a system penalty of ~4.1 dB at 10⁻⁹ BER is achieved.

First Report of Little cherry virus 2 in Flowering and Sweet Cherry Trees in China

Many viruses infect Prunus spp. and cause diseases on them. During a survey of stone fruit trees in 2008 and 2009, flowering cherry (Prunus serrulata) and sweet cherry (P. avium) trees with foliar chlorosis and reddening, stem deformity, and tree stunting were observed in private orchards in Anning and Fumin counties of Yunnan Province. Some sweet cherry trees with severe symptoms yielded small and few fruits and had to be removed. Leaf samples were collected from 68 flowering cherry and 30 sweet cherry trees, either symptomatic or asymptomatic, from private orchards and community gardens in Kunming and counties Anning, Chenggong, Fumin, Jinning, Ludian and Yiliang. Total nucleic acids were extracted with a CTAB extraction method and tested by reverse transcription (RT)-PCR assay using virus-specific primers. Little cherry virus 2 (LChV-2), Cherry virus A (CVA), Prunus necrotic ringspot virus (PNRSV), and Prune dwarf virus (PDV) were detected and infection rates were 68.4, 16.3, 9.2, and 7.1%, respectively. Infection of LChV-2 was common in all counties except Ludian where the orchards were healthy. Of 68 infected trees, 29 were found to be infected with LChV-2 and CVA, PDV or PNRSV. LChV-2 was detected in this study by RT-PCR using a pair of novel primers, LCV2-1 (5'-TTCAATATGAGCAGTGTTCCTAAC-3') and LCV2-4 (5'-ACTCGTCTTGTGACATACCAGTC-3'), in 59 flowering cherry (87%) and 8 sweet cherry (27%) trees, respectively. The primer pair was designed according to alignment of three available LChV-2 sequences (GenBank Nos. NC_005065, AF416335, and AF333237) to amplify the partial RNA-dependent RNA polymerase gene (ORF1b) of 781 bp. The amplicons of selected samples (Anning26 and Yiliang60) were sequenced directly and sequences of 651 bp (GenBank No. HQ412772) were obtained from both samples. Pairwise comparisons and phylogenetic analysis of the sequences show that the two isolates are identical to one another and share 92 to 96% at the amino acid (aa) sequence level to those of other isolates available in the GenBank database. The sequence data confirm that these isolates are a strain of LChV-2 and genetic variation among different strains is relatively high (2). Biological and serological assays are not available for the LChV-2 detection; therefore, the LChV-2 infections of these trees were further confirmed by RT-PCR using primer pair LCV2-5 (5'-TGTTTGTGTCATGTTGTCGGAGAAG-3') and LCV2-6 (5'-TGAATACCCGAGAACAAGGACTC-3'), which amplified the helicase domain (ORF1a) of ~451 bp. The amplicons from samples Anning26 and Yiliang60 were cloned and sequenced. The 408-bp sequences (excluding primer sequences) were 92 to 98% identical at the aa sequence level to those of other isolates, confirming again their viral origin. LChV-2 (genus Ampelovirus, family Closteroviridae) (4) has been associated with little cherry disease (LChD), a widespread viral disease of sweet and sour cherries (1,3). The virus is transferred between geographic areas mainly by propagated materials. Ornamental and sweet cherries are important crops in China and LChD has the potential to cause significant economic losses. Thus, certified clean stock should be used to establish new orchards. To our knowledge, this is the first report of LChV-2 in cherries in China. References: (1) N. B. Bajet et al. Plant Dis. 92:234, 2008. (2) W. Jelkmann et al. Acta Hortic. 781:321, 2008. (3) B. Komorowska and M. Cieslińska, Plant Dis. 92:1366, 2008. (4) M. E. Rott and W. Jelkmann. Arch. Virol. 150:107, 2005.

ηπ+ π- resonant structure around 1.8 GeV/c(2) and η(1405) in J/ψ → ωηπ+ π-

We present results of a study of the decay J/ψ → ωηπ+ π- using a sample of (225.2 ± 2.8) × 10(6) J/ψ events collected by the BESIII detector, and report the observation of a new process J/ψ → ωX(1870) with a statistical significance of 7.2σ, in which X(1870) decays to a(0)(±)(980)π±. Fitting to ηπ+ π- mass spectrum yields a mass M = 1877.3 ± 6.3(stat)(-7.4)(+3.4)(syst) MeV/c(2), a width Γ = 57 ± 12(stat)(-4)(+19)(syst) MeV/c(2), and a product branching fraction B(J/ψ → ωX) × B(X→a(0)(±)(980)π±) × B(a(0) (±)(980) → ηπ±) = [1.50 ± 0.26(stat)(-0.36)(+0.72) (syst)] × 10(-4). Signals for J/ψ → ωf(1)(1285) and J/ψ → ω η(1405) are also clearly observed and measured.

All-optical XOR logic gate for 40Gb/s DPSK signals via FWM in a silicon nanowire

We demonstrate an all-optical XOR logic function for 40Gb/s differential phase-shift keyed (DPSK) data signals in the C-band, based on four-wave mixing (FWM) in a silicon nanowire. Error-free operation with a system penalty of ~3.0dB and ~4.3dB at 10⁻⁹ BER is achieved.

Polymorphism H558R in the Human Cardiac Sodium Channel SCN5A Gene is Associated with Atrial Fibrillation

Atrial fibrillation (AF) is one of the most common sustained cardiac arrhythmias and its prevalence is increasing worldwide in line with the growing elderly population. Many single nucleotide polymorphisms and mutations are associated with AF, including the common loss-of-function histidine-558-to-arginine (H558R) polymorphism of the human cardiac sodium channel, voltage-gated, type V, α subunit (encoded by the SCN5A gene). The H558R polymorphism results from the T-C transition in the SCN5A gene. This study recruited 135 patients with AF and 296 healthy controls to scan for and perform targeted genotyping of the H558R polymorphism of the SCN5A gene. Logistic regression analysis showed that the TC and CC genotypes (i.e. genotypes that result in the R558 polymorphism) were significantly associated with an increased risk of developing AF. The R558 polymorphism conferred an odds ratio for AF of 3.451 (95% confidence interval 1.718, 6.931). In conclusion, this study provided evidence for the role of the H558R polymorphism of the SCN5A gene in increasing the susceptibility to AF.

Identification of a Novel de Novo STK11 Mutation in a Chinese Child with Peutz-Jeghers Syndrome

Peutz-Jeghers syndrome (PJS) is a rare autosomal dominant inherited disorder characterized by gastrointestinal polyposis and mucocutaneous pigmentation. PJS patients have an increased risk of cancer in multiple locations. Germ-line mutations in the STK11 gene have been found to be responsible for most PJS cases. DNA samples were obtained from a Chinese child with PJS, his clinically unaffected parents and 50 unrelated normal individuals, and the exons and flanking intronic sequences of the STK11 gene were analysed by polymerase chain reaction and direct sequencing. A novel de novo mutation (c.698_699insG; F234LfsX3) was identified in exon 5 of STK11, that resulted in a translational frameshift leading to termination at codon 236. This mutation was not found in the parents or unrelated individuals. These results enlarge the genotypic spectrum of STK11, particularly with regard to early onset, as observed in the present sporadic PJS case. This study may have important future implications for precise genotype-phenotype correlation research.

Observation of χ(c1) decays into vector meson pairs φφ, ωω, and ωφ

Using (106±4)×10⁻⁶ ψ(3686) events accumulated with the BESIII detector at the BEPCII e⁺e⁻ collider, we present the first measurement of decays of χ(c1) to vector meson pairs φφ, ωω, and ωφ. The branching fractions are measured to be (4.4±0.3±0.5)×10⁻⁴, (6.0±0.3±0.7)×10⁻⁴, and (2.2±0.6±0.2)×10⁻⁵, for χ(c1)→φφ, ωω, and ωφ, respectively, which indicates that the hadron helicity selection rule is significantly violated in χ(cJ) decays. In addition, the measurement of χ(cJ)→ωφ provides the first indication of the rate of doubly OZI-suppressed χ(cJ) decay. Finally, we present improved measurements for the branching fractions of χ(c0) and χ(c2) to vector meson pairs.

Metastatic endometrial stromal sarcoma of the lung: importance of immunohistochemical staining, clinical history and imaging studies

Proper evaluation of lung nodules is a difficult issue for clinical management of patients. Discriminating metastatic endometrial stromal sarcoma (ESS) from other primary spindle cell neoplasms of the lung using histological analysis can be challenging. This is particularly true when an adequate clinical history is lacking, because ESS metastasis can be delayed by a couple of decades. To emphasize the importance of the correlation of pathological findings with clinical history and imaging studies, we investigated 11 cases of ESS (seven low grade and four high grade) metastatic to the lung. All cases presented with one to multiple unilateral or bilateral lung nodules that were detected by chest computed tomography. Primary ESS was diagnosed from hysterectomy specimens except for one by endometrial biopsy, 0.5 to 23 years prior to metastasis. Immunohistochemical studies showed that all ESS cases were moderately to strongly positive for Bcl-2 and CD10 with >50% of tumor cells stained, except for one high grade ESS that was negative for CD10. Eight (72.7%) and seven (63.6) of the 11 cases showed positive estrogen and progesterone receptors, respectively, with a majority of positive cases showing diffuse and moderate to strong staining. Strong but patchy staining for CD34 was detected in one (9.1%) case with smooth muscle differentiation. CK7 and TTF-1 were negative in all cases. Two (18.2%) cases exhibited patchy and strong positivity for caldesmon. Two (18.2%) low grade ESS cases showed moderate to strong AE1/AE3 positivity in >50% of tumor cells, one of which also showed moderate CK19 and Cam 5.2 staining in >30% of tumor cells. One should be cautious when assessing spindle cell neoplasms of the lung in women with a history of hysterectomy. Correlation of clinical history and imaging studies with histological and immunohistochemical findings is essential to diagnosis of metastatic ESS to the lung.

Percutaneous vertebroplasty for pain management in spinal metastasis with epidural involvement

Percutaneous vertebroplasty (PVP) has been widely used for the treatment of painful malignant lesions of the spine. Spinal metastasis with epidural involvement, with or without symptoms of neurologic compression, is regarded by some authors as a contraindication or relative contraindication to the procedure. To evaluate safety and effectiveness of PVP in pain management of spinal metastasis with epidural involvement, we retrospectively analyzed PVP in 32 patients with metastatic disease, who presented with at least one vertebral lesion with destruction of the posterior vertebral body wall or epidural extension of tumor. Among these patients, nine had signs of spinal cord or cauda equina compression. Procedural safety was evaluated by any post-procedure adverse events. The PVP analgesic efficacy was evaluated by follow-up neurological examination. Pain intensity was scored on a visual analog scale scored from 0 (no pain) to 10 (maximum pain intensity). The effective pain relief was defined as at least 50% improvement in pain score as compared with pre- procedure baseline. Follow-up assessments were performed at 1 day; 1 week; 1, 3, and 6 months after the procedure. Fifty-three vertebrae in 32 patients were treated in this group. Analgesic efficacy in survival patients was rated at 97% (31/32) at 1day and 1 week, 86.7% (26/30) at 1 month, 82.3% (24/29) at 3 months, and 76.9% (20/26) at 6 months after procedure. Leakage of PMMA was detected in 64% (33/53) treated vertebrae. No systemic complications were observed in all treated patients.

Clinical observation of 73 nasopharyngeal carcinoma patients treated by helical tomotherapy: the China experience

The preliminary short-term clinical outcome of 73 nasopharyngeal carcinoma (NPC) patients treated with helical tomotherapy at our cancer institute has been evaluated. Between September 2007 and September 2009, 73 newly diagnosed NPC patients were treated with helical tomotherapy. The distributions of clinical stages according to the UICC 2002 Staging System were: 6, 27, 24, and 16 for Stage I, IIa-b, III, and IVa-b, respectively. The prescription dose was 70-74 Gy/33F to planning gross tumor volume containing the primary tumor and positive lymph nodes, with 60-62.7 Gy/33F to high risk planning target volume, while delivering 52-56 Gy/33F to low risk planning target volume. Twenty-four patients were treated with radiation therapy as single modality, 25 with concurrent cisplatin-based chemotherapy with or without anti-EGFR monoclonal antibody therapy, and 24 with concurrent anti-EGFR monoclonal antibody therapy. Setup errors were analyzed. Side-effects were evaluated with the established RTOG/EORTC criteria. Average beam-on-time was 468.8 sec/F (396.7-696.1 sec). The setup errors in the lateral, longitudinal and vertical directions were 0.00 ± 1.79 mm, -0.55± 2.17 mm and 0.38 ± 1.43 mm, corresponding to 3.80 mm, 4.20 mm, and 2.46 mm as the CTV-PTV margin in these directions. The grade 0, 1, 2 and 3 acute skin toxicity was 2.7%, 76.7%, 13.8% and 6.8%; the grade 0, 1, 2 and 3 acute mucositis was 1.4%, 32.9%, 60.2% and 5.5%; and the grade 0, 1, 2 and 3 acute xerostomia was 4.0%, 45.3%, 50.7% and 0, respectively. Only 5 patients suffered from grade 3 or 4 leucopenia. Xerostomia resolved with passing of time and no grade 2 or more xerostomia was noted one year after radiation therapy. Concurrent chemotherapy significantly increased incidence of severe acute toxicities. One month after radiation therapy the remission rates of primary tumor and positive lymph nodes were 91.8% and 98.1%, respectively. The median follow-up was 14.8 months. The one-year relapse-free survival, distant metastasis-free survival and overall survival was 95.6%, 97.2% and 94.8%, respectively. In conclusion, the incidence of severe acute toxicities and late xerostomia was relatively infrequent for NPC patients treated with helical tomotherapy. The long-term clinical outcome for these patients is under investigation.

RNA interference of ace1 and ace2 in Chilo suppressalis reveals their different contributions to motor ability and larval growth

Acetylcholinesterase (AChE, EC 3.1.1.7) is a key enzyme in terminating synaptic transmission. We knocked down the expression of Csace1 or Csace2 using chemically synthesized small interfering RNAs (siRNAs) designed from divergent regions. The mRNA abundance of the two ace genes was reduced to 50-70% of control levels. The enzyme activities were decreased to 40-70%. Silencing of Csace1 or Csace2 resulted in a ~25% mortality rate. Knockdown of Csace1 had major effects on larval growth inhibition and resulted in reduced larval weight and length, malformation and motor disability, whereas silencing of Csace2 had only minor effects. These results suggested that both AChE-1 and AChE-2 have important roles in maintaining life in this insect and indicated that AChE-1 might have nontypical functions in regulating larval growth and motor ability.