Prognostic nomogram for nonresectable pancreatic cancer treated with gemcitabine-based chemotherapy

Background:

A nomogram is progressively being used as a useful predictive tool for cancer prognosis. A nomogram to predict survival in nonresectable pancreatic cancer treated with chemotherapy has not been reported.

Methods:

Using prospectively collected data on patients with nonresectable pancreatic cancer receiving gemcitabine-based chemotherapy at five Japanese hospitals, we derived a predictive nomogram and internally validated it using a concordance index and calibration plots.

Results:

In total, 531 patients were included between June 2001 and February 2013. The American Joint Committee on Cancer (AJCC) TNM stages were III and IV in 204 and 327 patients, respectively. The median survival time of the total cohort was 11.3 months. A nomogram was generated to predict survival probabilities at 6, 12, and 18 months and median survival time, based on the following six variables: age; sex; performance status; tumour size; regional lymph node metastasis; and distant metastasis. The concordance index of the present nomogram was higher than that of the AJCC TNM staging system at 12 months (0.686 vs 0.612). The calibration plots demonstrated good fitness of the nomogram for survival prediction.

Conclusions:

The present nomogram can provide valuable information for tailored decision-making early after the diagnosis of nonresectable pancreatic cancer.

Ovarian and hormonal responses to follicular phase administration of investigational metastin/kisspeptin analog, TAK-683, in goats

This study evaluated the effects of follicular phase administration of TAK-683, an investigational metastin/kisspeptin analog, on follicular growth, ovulation, luteal function and reproductive hormones in goats. After confirmation of ovulation by transrectal ultrasonography (Day 0), PGF2α (2 mg/head of dinoprost) was administered intramuscularly on Day 10 to induce luteal regression. At 12 h after PGF2α administration, intravenous administration of vehicle or 35 nmol (50 μg)/head of TAK-683 was performed in control (n = 4) and treatment (n = 4) groups, respectively. Blood samples were collected at 6-h intervals for 96 h and then daily until the detection of subsequent ovulation (second ovulation). After the second ovulation, ultrasound examinations and blood sampling were performed every other day or daily until the subsequent ovulation (third ovulation). Mean concentrations of LH and FSH in the treatment group were significantly higher 6 h after TAK-683 treatment than those in the control group (12.0 ± 10.7 vs 1.0 ± 0.7 ng/ml for LH, 47.5 ± 28.2 vs 15.1 ± 3.4 ng/ml for FSH, p < 0.05), whereas mean concentrations of oestradiol in the treatment group decreased immediately after treatment (p < 0.05) as compared with the control group. Ovulation tended to be delayed (n = 2) or occurred early (n = 1) in the treatment group as compared with the control group. For the second ovulation, ovulatory follicles in the treatment group were significantly smaller in maximal diameter than in the control group (3.8 ± 0.5 vs 5.4 ± 0.2 mm, p < 0.05, n = 3). Administration of TAK-683 in the follicular phase stimulates gonadotropin secretion and may have resulted in ovulation of premature follicles in goats.

The expression of Fn14 via mechanical stress-activated JNK contributes to apoptosis induction in osteoblasts

Bone mass is maintained by the balance between the activities of bone-forming osteoblasts and bone-resorbing osteoclasts. It is well known that adequate mechanical stress is essential for the maintenance of bone mass, whereas excess mechanical stress induces bone resorption. However, it has not been clarified how osteoblasts respond to different magnitudes of mechanical stress. Here we report that large-magnitude (12%) cyclic stretch induced Ca(2+) influx, which activated reactive oxygen species generation in MC3T3-E1 osteoblasts. Reactive oxygen species then activated the ASK1-JNK/p38 pathways. The activated JNK led to transiently enhanced expression of FGF-inducible 14 (Fn14, a member of the TNF receptor superfamily) gene. Cells with enhanced expression of Fn14 subsequently acquired sensitivity to the ligand of Fn14, TNF-related weak inducer of apoptosis, and underwent apoptosis. On the other hand, the ASK1-p38 pathway induced expression of the monocyte chemoattractant protein 3 (MCP-3) gene, which promoted chemotaxis of preosteoclasts. In contrast, the ERK pathway was activated by small-magnitude stretching (1%) and induced expression of two osteogenic genes, collagen Ia (Col1a) and osteopontin (OPN). Moreover, activated JNK suppressed Col1a and OPN induction in large-magnitude mechanical stretch-loaded cells. The enhanced expression of Fn14 and MCP-3 by 12% stretch and the enhanced expression of Col1a and OPN by 1% stretch were also observed in mouse primary osteoblasts. These results suggest that differences in the response of osteoblasts to varying magnitudes of mechanical stress play a key role in switching the mode of bone metabolism between formation and resorption.

Improving adenovirus vector-mediated RNAi efficiency by lacking the expression of virus-associated RNAs

Several studies have reported that short hairpin RNA (shRNA)-mediated RNA interference (RNAi) was competitively inhibited by the expression of adenovirus (Ad)-encoded small RNAs (VA-RNAs), which are expressed from a replication-incompetent Ad vector, as well as a wild-type Ad; however, it remained to be clarified whether an shRNA-expressing Ad vector-mediated knockdown was inhibited by VA-RNAs transcribed from the same Ad vector genome. In this study, we demonstrated that a lack of VA-RNA expression from the Ad vector leads to an increase in knockdown efficiencies of Ad vector-mediated RNAi. In the cells transduced with a first-generation Ad vector (FG-Ad) expressing shRNA (FG-Ad-shRNA), the copy numbers of shRNA and VA-RNAs incorporated into the RNA-induced silencing complex (RISC) was comparable. In contrast, higher amounts of shRNA were found in the RISC when the cells were transduced with an shRNA-expressing helper-dependent Ad (HD-Ad) vector, in which all viral genes, including VA-RNAs, were deleted (HD-Ad-shRNA), compared with FG-Ad-shRNA. HD-Ad vectors expressing shRNA against luciferase and p53 showed 7.4% and 37.3% increases in the knockdown efficiencies compared to the corresponding FG-Ad-shRNA, respectively, following in vitro transduction. Furthermore, higher levels of knockdown efficiencies were also found by the transduction with shRNA-expressing Ad vectors lacking VA-RNA expression (AdΔVR-shRNA) than by transduction with FG-Ad-shRNA. These results indicate that VA-RNAs expressed from an Ad vector inhibit knockdown by the shRNA-expressing Ad vector and that HD-Ad-shRNA and AdΔVR-shRNA are a powerful framework for shRNA-mediated knockdown.

Simple push coating of polymer thin-film transistors

Organic semiconductors may be processed in solution under ambient conditions; however, liquid manipulation on hydrophobic surfaces is difficult, which may hinder development of devices. Here, a push-coating technique is used to produce large-area semiconducting polymer films over hydrophobic surfaces.

Solution processibility is a unique advantage of organic semiconductors, permitting the low-cost production of flexible electronics under ambient conditions. However, the solution affinity to substrate surfaces remains a serious dilemma; liquid manipulation is more difficult on highly hydrophobic surfaces, but the use of such surfaces is indispensable for improving device characteristics. Here we demonstrate a simple technique, which we call ‘push coating’, to produce uniform large-area semiconducting polymer films over a hydrophobic surface with eliminating material loss. We utilize a poly(dimethylsiloxane)-based trilayer stamp whose conformal contact with the substrate enables capillarity-induced wetting of the surface. Films are formed through solvent sorption and retention in the stamp, allowing the stamp to be peeled perfectly from the film. The planar film formation on hydrophobic surfaces also enables subsequent fine film patterning. The technique improves the crystallinity and field-effect mobility of stamped semiconductor films, constituting a major step towards flexible electronics production.

TLR7 stimulation of APCs results in inhibition of IL-5 through type I IFN and Notch signaling pathways in human peripheral blood mononuclear cells

TLR7 agonists modulate Th2 immune responses through mechanisms that have not been fully elucidated. Suppression of IL-5 production from Ag- or phytohemagglutinin-stimulated human PBMCs by the TLR7 antedrug AZ12441970 was mediated via type I IFN-dependent and type I IFN-independent mechanisms through TLR7 activation of plasmacytoid dendritic cells, B cells, and monocytes. The type I IFN-dependent inhibition of T cell-derived IL-5 was mediated by IFN-α acting directly on activated T cells. IL-10 was shown not to be involved in the type I IFN-independent inhibition of IL-5 and the mechanism of inhibition required cell-cell interaction. Notch signaling was implicated in the inhibition of IL-5, because addition of a γ-secretase inhibitor blocked the type I IFN-independent suppression of IL-5. Accordingly, AZ12441970 induced high levels of the notch ligands Dll1 and Dll4 mRNA, whereas immobilized DLL4 resulted in the suppression of IL-5 production. Therefore, we have elucidated two mechanisms whereby TLR7 agonists can modulate IL-5 production in human T cells. The suppression of Th2 cytokines, including IL-5, would be of benefit in diseases such as atopic asthma, so we assessed TLR7 function in PBMC from asthmatics and showed equivalent activity compared with healthy volunteers. Demonstrating this function is intact in asthmatics and knowing it links to suppression of Th2 cytokines support the case for developing such compounds for the treatment of allergic disease.

Salt is an oxidative stressor for gastric epithelial cells

Salt/NaCl has been reported to induce necrosis in gastric mucosal cells, however, the mechanisms for gastric injury by salt are not clarified. In this study, we elucidated whether salt is an oxidative stress inducer via mitochondrial injury on rat gastric epithelial cells (RGM-1) in 300, 450, 650 and 1000 mM of NaCl-contained medium. To clarify whether salt-induced reactive oxygen species (ROS) is derived from mitochondria, we also investigated a salt-induced ROS production in manganese superoxide dismutase overexpressing cells (RGM-MnSOD). MnSOD is a specific scavenger for superoxide anion produced from mitochondria. The results showed that cellular injuries in RGM-MnSOD were significantly less severe than that in normal RGM-1. The electron paramagnetic resonance (EPR) studies also provided an evidence that the salt-derived superoxide production in RGM-MnSOD was less than that in normal RGM-1. These results indicated that salt is not merely a necrotizing factor for gastric epithelial cells, but also an oxidative stress inducer.

Abstract P2-06-01: Breast-to-breast metastasis can cause hormone-receptor positive/triple negative bilateral synchronous tumors

Background: Prior work suggests that synchronous bilateral breast cancers may be clonal, with one tumor a metastasis, although prior techniques lacked resolution to prove this relationship. We used deep whole exome and shallow whole genome sequencing to compare bilateral tumors in two cases. In both cases, tumors were invasive and node negative with one tumor ER+/PR+/HER2− (HR+) lobular and the other triple negative (TN) ductal. Case 1 is a 75-year-old African American woman and Case 2 a 70-year-old white woman. With 44 and 12 months of follow up, respectively, neither patient has recurred.

Methods: Agilent SureSelect All Exon 50Mb Target Enrichment Kits were used for exome capture. Paired-end sequencing was performed with 200 base pair reads on the Illumina HiSeq 2000. Sequencing depth was targeted to cover 80% of the genome at 100x for three tumors with 70% cellularity, 200x for one tumor with 40% cellularity and 30x for germline. Tumor and germline exome results were compared to identify high confidence somatic single nucleotide variants (HC SNV). HC SNV's were called using GATK and stringent custom filtering to avoid false positives resulting from unrecognized germline single nucleotide polymorphisms. For each tumor pair, we define a clonality likelihood score (CLS) as the ratio of the number of HC SNV called at the same site and with the same alternate base in both tumors, to the total number of sites with an HC SNV called in either tumor. For comparison we analyzed the called SNV data from The Cancer Genome Atlas (TCGA) for exome sequenced HR+ or TN breast cancers.

Results: In Case 1, of 102 HC SNVs called in either tumor, 82 were shared, for a CLS of 80.3%. Additionally, 11 shared SNVs were synonymous, consistent with clonality. Lastly the non-shared HC SNVs were asymmetrically found in the TN tumor, consistent with clonal evolution during metastasis. Copy number analysis (CNA) showed Case 1 to have a deletion in 6q, including the ESR1 gene, unique to the TN tumor.

To assess significance of the CLS, we found three primary/metastatic clonal pairs in the TCGA to serve as positive controls. To serve as negative controls, from 357 ER+ and 46 TN primary TCGA tumors, we formed a total of 16,422 independent ER+/TN pairs. For the 3 clonal TCGA pairs, the CLS values were 39.3%, 58.5% and 60.0%. Most of the independent TCGA pairs had a CLS of zero (98.5%), with a maximum CLS of 2.8%. As the CLS for Case 1 lies above maximum observed CLS among 16,422 independent tumor pairs, we reject the hypothesis that this tumor pair is independent, at p &lt; 0.0001. For Case 2, of 222 HC SNV sites, 5 were shared for a CLS of 2.3%, consistent with independence.

Conclusion: Somatic single nucleotide mutations identified by exome sequencing found that the two tumors in Case 1 share &gt;80% of SNVs, consistent with clonal evolution of metastasis. The two tumors from Case 2 have few shared SNVs, consistent with independent origin. CNA results were consistent. This is the first clonality analysis reported from deep sequencing of phenotypically discordant synchronous bilateral breast cancers, and demonstrates that next-generation sequencing can distinguish clonal from independent tumor pairs with high confidence.

Funding: The Breast Cancer Research Foundation

Citation Information: Cancer Res 2012;72(24 Suppl):Abstract nr P2-06-01.

Risk factors for and prognosis of hemorrhagic cystitis after allogeneic stem cell transplantation: retrospective analysis in a single institution

Hemorrhagic cystitis (HC) is a major complication after allogeneic stem cell transplantation (allo-SCT) and can be life threatening. To analyze risk factors and prognosis, we retrospectively reviewed 249 cases receiving allo-SCT in our institution. Median age was 47 years (13-72 years). Disease status at SCT was progressive in 73 cases. Conditioning was myeloablative (MAC) in 146 cases. Acute graft-versus-host disease (aGVHD) grade II-IV treated with prednisolone occurred in 82 cases, and cytomegalovirus (CMV) was reactivated in 91 cases. HC was reported in 47 cases at a median of 35 days (7-469 days) after SCT, and 34 (72.3%) cases recovered after a median of 19.5 days (2-252 days). In univariate analysis, the identified risk factors for HC included age over 45 years, progressive disease status, MAC, aGVHD treated with prednisolone, and CMV reactivation. In multivariate analysis, older age, MAC, and CMV remained independent predictors (hazard ratios: 2.35, 3.50, and 2.87). In patients with severe HC, percentage recovery was lower (3 in 13 cases; 23.1%) and the median duration was longer (54 days) than in those with moderate HC (31 in 36 cases; 86.1%, 17 days, P < 0.01). Treatment-related mortality was also higher (59.1%, P = 0.03) and overall survival was poorer (16.7%, P < 0.01) at 1 year after SCT. Prospective studies should be started considering prophylactic antiviral administration in high-risk patients such as those identified in this study.

Hybrid energy-minimization simulation of equilibrium droplet shapes on hydrophilic/hydrophobic patterned surfaces

We have developed an efficient algorithm for simulating the equilibrium shape of a microdroplet placed on a flat substrate that has a fine, discontinuous, and arbitrarily shaped hydrophilic/hydrophobic patterned surface. The method uses a hybrid energy-minimization technique that combines the direct search method to determine the droplet shape around solid/liquid contact lines with the gradient descent method for the other parts of the droplet surface. The method provides high-convergence at a low computational cost with sufficient mesh resolution, providing a useful tool for the optimal design of printed electronic devices.