Abstract P6-07-35: Dragonfly Effect or Ironic Paradox: Prognostic Implication of Postsurgical Drain in Breast Cancer Patients

Background: Surgical removal of primary breast cancer may result in subsequent alterations of host milieu. Massive clinical data have indicated that surgical extirpation favorably modifies the natural history for some patients, but it may also precipitate the metastatic outgrowth for others. Drainage fluid, harvested from a post-surgical wound, appears to be a physiological response to surgical trauma. However, few clinicians have recognized that the volume of wound drain might mirror the postoperative recurrence kinetics.

Methods: A total of 1439 patients were selected retrospectively from a large database of patients who underwent surgery between Jan 1, 2000 and Dec 31, 2002 in Fudan University Shanghai Cancer Center, Shanghai, China. The Spearman rank correlation analysis was conducted to evaluate the association between drainage volume of postoperative day 1 (POD1) and clinicopathological parameters, which included age at diagnosis, body weight at diagnosis, total number of excised axillary lymph nodes (ALNs), time to drainage volume less than 30ml (TTV30), total protein and albumin concentrations in serum. Survival curves were performed with Kaplan–Meier method and annual recurrence hazard was estimated by hazard function.

Results: Drainage volume of POD1 was positively correlated with age at diagnosis (Spearman's P < 0.001), weight at diagnosis (P <0 .001) and number of excised ALNs (P <0 .001) and TTV30 (P <0 .001), whereas it was inversely correlated with total protein concentration in serum (p = 0.028). We also observed that drainage volume of POD1 was significantly higher in patients with larger tumors (P < 0.001) and ALNs involvement (P = 0.030).

In the univariate survival analysis, there was less recurrence and death in patients with lower drainage volume of POD1 (both p = 0.006). Cox proportional hazards regression analysis revealed that drainage volume of POD1 was an independent predictor of recurrence-free survival (RFS; p = 0.035) and overall survival (OS; p = 0.047). Additionally, triple negative patients with larger volume of POD1 seemed to have poorer RFS (log-rank p = 0.022; Cox model P < 0.05) and OS (log-rank p = 0.015; Cox model P < 0.05).

Conclusions: Our study suggests that postsurgical drainage volume was strongly correlated with prognosis in breast cancer patients. The aim of this study was not only to enlighten novel prognostic factors, but also to infer that some host related characteristics such as extent of reaction to surgery play very important roles in the growth of micro-metastases. Therefore, integration of both host and tumor related factors be more precise to predict relapse risk than current modalities such as the St Gallen criteria, Oncotype-21 and Mammaprint etc. Further research on the underlying mechanism of this phenomena may lead the way to new adjuvant treatment targets and strategies.

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P6-07-35.

Visualizing orbital angular momentum of plasmonic vortices

Plasmonic vortices (PVs) are generated by focusing a radially polarized optical vortex (OV) beam onto a metal surface. The intensity distribution of the PV is registered with a near-field scanning optical microscopy and agrees well with a theoretical prediction as well as numerical calculation. Beside the dark central spot, the numerical calculation also shows an azimuthal Poynting vector belonging to the PV, implying that the orbital angular momentum (OAM) was transferred from the radially polarized OV. To directly verify the OAM, plasmonic trapping experiments with gold micrometer particles are performed and the particle rotation is visualized. Further experiments by varying the topological charge of radially polarized OVs show the corresponding changes in rotation in terms of speed and radius.

Emerging players in the initiation of eukaryotic DNA replication

Faithful duplication of the genome in eukaryotes requires ordered assembly of a multi-protein complex called the pre-replicative complex (pre-RC) prior to S phase; transition to the pre-initiation complex (pre-IC) at the beginning of DNA replication; coordinated progression of the replisome during S phase; and well-controlled regulation of replication licensing to prevent re-replication. These events are achieved by the formation of distinct protein complexes that form in a cell cycle-dependent manner. Several components of the pre-RC and pre-IC are highly conserved across all examined eukaryotic species. Many of these proteins, in addition to their bona fide roles in DNA replication are also required for other cell cycle events including heterochromatin organization, chromosome segregation and centrosome biology. As the complexity of the genome increases dramatically from yeast to human, additional proteins have been identified in higher eukaryotes that dictate replication initiation, progression and licensing. In this review, we discuss the newly discovered components and their roles in cell cycle progression.

Orc2 protects ORCA from ubiquitin-mediated degradation

Origin recognition complex (ORC) is highly dynamic, with several ORC subunits getting posttranslationally modified by phosphorylation or ubiquitination in a cell cycle-dependent manner. We have previously demonstrated that a WD repeat containing protein ORC-associated (ORCA/LRWD1) stabilizes the ORC on chromatin and facilitates pre-RC assembly. Further, ORCA levels are cell cycle-regulated, with highest levels during G(1), and progressively decreasing during S phase, but the mechanism remains to be elucidated. We now demonstrate that ORCA is polyubiquitinated in vivo, with elevated ubiquitination observed at the G(1)/S boundary. ORCA utilizes lysine-48 (K48) ubiquitin linkage, suggesting that ORCA ubiquitination mediates its regulated degradation. Ubiquitinated ORCA is re-localized in the form of nuclear aggregates and is predominantly associated with chromatin. We demonstrate that ORCA associates with the E3 ubiquitin ligase Cul4A-Ddb1. ORCA is ubiquitinated at the WD40 repeat domain, a region that is also recognized by Orc2. Furthermore, Orc2 associates only with the non-ubiquitinated form of ORCA, and Orc2 depletion results in the proteasome-mediated destabilization of ORCA. Based on the results, we suggest that Orc2 protects ORCA from ubiquitin-mediated degradation in vivo.

Derivation and characterization of matched cell lines from primary and recurrent serous ovarian cancer

Background

Cell line models have proven to be effective tools to investigate a variety of ovarian cancer features. Due to the limited number of cell lines, particularly of the serous subtype, the heterogeneity of the disease, and the lack of cell lines that model disease progression, there is a need to further develop cell line resources available for research. This study describes nine cell lines derived from three ovarian cancer cases that were established at initial diagnosis and at subsequent relapse after chemotherapy.

Methods

The cell lines from three women diagnosed with high-grade serous ovarian cancer (1369, 2295 and 3133) were derived from solid tumor (TOV) and ascites (OV), at specific time points at diagnosis and relapse (R). Primary treatment was a combination of paclitaxel/carboplatin (1369, 3133), or cisplatin/topotecan (2295). Second line treatment included doxorubicin, gemcitabine and topotecan. In addition to molecular characterization (p53, HER2), the cell lines were characterized based on cell growth characteristics including spheroid growth, migration potential, and anchorage independence. The in vivo tumorigenicity potential of the cell lines was measured. Response to paclitaxel and carboplatin was assessed using a clonogenic assay.

Results

All cell lines had either a nonsense or missense TP53 mutations. The ability to form compact spheroids or aggregates was observed in six of nine cell lines. Limited ability for migration and anchorage independence was observed. The OV3133(R) cell line, formed tumors at subcutaneous sites in SCID mice. Based on IC₅₀ values and dose response curves, there was clear evidence of acquired resistance to carboplatin for TOV2295(R) and OV2295(R2) cell lines.

Conclusion

The study identified nine new high-grade serous ovarian cancer cell lines, derived before and after chemotherapy that provides a unique resource for investigating the evolution of this common histopathological subtype of ovarian cancer.

Trends in the optical and redox properties of tetraphenyltetraphenanthroporphyrins

The results of TD-DFT calculations for a series of tetraaryltetraphenanthroporphyrins containing para-substituents with differing electron donating and accepting properties are compared to the observed optical and redox properties and Michl's perimeter model is used as a conceptual framework for analyzing the results.

High expression of EphA1 in esophageal squamous cell carcinoma is associated with lymph node metastasis and advanced disease

Eph receptors play important roles in the development of cancer. The present study aimed to investigate the expression of EphA1 and its clinicopathologic significance in esophageal squamous cell carcinoma (ESCC). The expression levels of the EphA1 transcript and protein were compared between ESCC and matched normal mucosa in the same patient. High expression levels of the EphA1 transcript and protein were detected in 25.6% (21/82) and 23.2% (19/82) of tumors compared with matched normal mucosa. The up-regulation of EphA1 transcript in tumors was positively associated with differentiation (p = 0.002), disease stage (p = 0.034), and lymph node metastasis (p = 0.042). Increased expression of EphA1 protein in tumors was more often observed in patients with well-differentiated tumors (p = 0.004), lymph node metastasis (p = 0.028), and advanced tumor stage (p = 0.008). EphA1 protein expression was detected in intraepithelial neoplasias as well. Decreased expression of EphA1 protein was detected in 65.2% (15/23) of samples with low-grade neoplasia and in 85.3% (8/15) of samples with high-grade intraepithelial neoplasia. Increased staining of EphA1 protein was not detected in low-grade intraepithelial neoplasia samples, but was detected in 21.3% (2/15) of high-grade intraepithelial neoplasia samples. Taken together, our results show that EphA1 appears to be a differentiation marker for esophageal squamous cells, and its increased expression is positively associated with lymph node metastasis and advanced disease stage.

HGFK1 inhibits bone metastasis in breast cancer through the TAK1/p38 MAPK signaling pathway

Breast cancer metastasis to bone represents a devastating complication of advanced breast cancer, frequently resulting in significant increases in morbidity and mortality. An understanding of the mechanisms that govern breast cancer metastasis at the molecular level should lead to more effective therapies. Recently, the kringle 1 domain of human hepatocyte growth factor (HGFK1) was identified as a candidate metastasis suppressor gene. Here, we investigated whether HGFK1 is a key regulator of breast cancer bone metastasis. Of the 193 human breast carcinoma tissue samples examined, HGFK1 expression was relative higher in 82 (42.4%) by western blot and in 84 (43.5%) by quantitative real-time PCR. The higher expression of HGFK1 was significantly associated with a better prognostic value (P<0.001) and inversely correlated with bone metastasis (P=0.003). The efficacy of adeno-associated virus carrying HGFK1 (AAV-HGFK1) in osteolytic bone metastasis was then evaluated using an in vivo bone metastasis model. AAV-HGFK1 significantly inhibited osteolytic bone metastasis and prolonged the survival of mice in this model (P<0.01). In vitro, HGFK1 expression resulted in significant anti-invasion effects, enhanced the phosphorylation of TAK1 (transforming growth factor-β-activated kinase 1), p38 MAPK (mitogen-activated protein kinase) and MAPKAPK2 (MAPK-activated protein kinase 2) and decreased the expression of receptor activator of nuclear factor-κB (RANK), which was abrogated by the p38 MAPK inhibitor SB203580. This study shows for the first time that HGFK1 significantly inhibits the metastasis of breast cancer to bone by activating the TAK1/p38 MAPK signaling pathway and inhibiting RANK expression. Thus, AAV-HGFK1 treatment represents a potential therapy for bone metastasis in breast cancer.

Synthesis, structure and spectroscopic properties of a porphycene-ReI complex

A new type of rhenium(I) tricarbonyl porphycene complex is reported based on a reaction between free-base 2,3,6,7,12,13,16,17-octaethylporphycene (H2OEPc) and Re(CO)5Cl . As is the case with tetraphenylporphyrin (TPP), a complex containing only one Re(CO)3 groups, which retains a pyrrole proton, can be isolated and characterized in addition to a bis- Re(I) complex. The ReI(HOEPc)(CO)3 complex was characterized by 1H NMR, 13C NMR, MS, IR, UV-visible, and MCD spectroscopy and cyclic voltammetry. A single crystal was successfully obtained, which enabled the determination of the X-ray structure.