Intravascular recovery of VWF and FVIII following intraperitoneal injection and differences from intravenous and subcutaneous injection in mice

Intravenous infusion studies in humans suggest that both von Willebrand factor (VWF) and factor VIII (FVIII) remain intravascular in contrast to other coagulation proteins. We explored whether infusion of VWF and FVIII by either intraperitoneal (i.p.) or subcutaneous (s.c.) injection would result in efficient absorption of these large proteins into the vascular circulation. FVIII(null) or VWF(null) mice were infused with plasma-derived or recombinant VWF and/or FVIII by i.p., s.c., or intravenous (i.v.) injection. Both VWF and FVIII were absorbed into the blood circulation after i.p. injection with a peak between 2 and 4 h at levels similar to those observed in mice infused intravenously. In contrast, neither VWF nor FVIII was detected in the plasma following s.c. injection. Although i.v. injection achieved peak plasma levels quickly, both human VWF and FVIII rapidly decreased during the first 2 h following i.v. injection. Following both i.v. and i.p. infusion of VWF, the multimeric structure of circulating VWF was similar to that observed in the infusate. These results demonstrate that both VWF and FVIII can be efficiently absorbed into the blood circulation following i.p., but not s.c. injection, indicating that i.p. administration could be an alternative route for VWF or FVIII infusion.

A novel monoclonal antibody against human CD80 and its immune protection in a mouse lupus-like disease

Blockade of the interactions between CD28/CTLA-4 and their ligands, CD80 (B7, B7.1)/CD86 (B70, B7.2), is an attractive means to induce antigen-specific peripheral tolerance in autoimmune disease and organ transplantation. In this study, we generated and characterized a monoclonal antibody (Clone 4E5) against human CD80. 4E5 could recognize both human and mouse CD80 and suppress mixed lymphocyte reaction in vitro. To investigate their potency for clinical use, we further administrated 4E5 to a mouse lupus-like disease model (C57BL/J6) induced by Pristane. 4E5 could inhibit the immune response and attenuate the severity of lupus-like disease. The data showed 4E5 function and suggested that blockade of CD80/CD28 co-stimulatory signal pathway with 4E5 is a promising strategy to decelerate the progression of lupus-like disease and other autoimmune diseases.

MicroRNAs of rat articular cartilage at different developmental stages identified by Solexa sequencing

BACKGROUND

Expression profiles of microRNAs (miRNAs) can shape the repertoire of proteins expressed in development, differentiation and diseases. This study aimed to identify miRNA profile of articular cartilage at different developmental stages in rats.

METHODS

Three small RNA libraries were constructed from the femoral head cartilage of Sprague-Dawley (SD) rats at postnatal day 0, day 21 and day 42 and sequenced by a deep sequencing approach. Then a bioinformatics approach was employed to distinguish genuine miRNAs from small RNAs represented in the mass sequencing data. The expression of indicated miRNAs was determined by stem-loop RT-qPCR to valuate the consistency with Solexa sequencing.

RESULTS

Two hundred and fifty-eight of 310 known miRNA and miRNA* genes were organized into 91 compact clusters. Two hundred and forty-six miRNAs were detected in all three small RNA libraries of rat articular cartilage. Forty-six, fifty-two and fifty-six miRNA* genes were identified from three small RNA libraries, respectively, and 86 novel miRNA candidate genes were found simultaneously. In addition, 23 known miRNAs were up-regulated (fold change ≥ 4); six were down-regulated (fold change ≤ -4) during articular cartilage development. The predicted targets of differentially expressed miRNAs were locally secreted factors and transcription factors that regulate proliferation and differentiation of chondrocytes. The same expression tendency of indicated miRNAs during articular cartilage development stages was observed by using Solexa sequencing and stem-loop RT-qPCR.

CONCLUSION

Our study provided a unique opportunity to decipher how the elaboration of the miRNA repertoire contributes to the development process of articular cartilage.

Downregulation of transcription factor SOX2 in cancer stem cells suppresses growth and metastasis of lung cancer

Background:

The cancer stem cell hypothesis suggests that neoplastic clones are maintained exclusively by a small subpopulation of cells, which have indefinite proliferation and differentiation potentials and give rise to phenotypically diverse cancer cells. Cancer stem cells have been isolated by their ability to efflux Hoechst 33342 dye and are referred to as the ‘side population’ (SP).

Methods and results:

The Hoechst efflux assay was used to isolate and characterize the SP from murine D121 lung carcinoma cells. Here, we demonstrated that D121-SP cells contain cancer stem cell characteristics, that is, upregulation of the transcription factors SOX2 and Oct 4 in D121-SP cells. In addition, the migration of D121-SP was decreased, and apoptosis of D121-SP was upregulated following knocking down of SOX2 in D121 cells. Importantly, downregulation of SOX2 in D121 cells markedly suppressed their metastatic potential in syngeneic mice.

Conclusions:

These results suggest that the SP is an enriched source of lung tumour cells with stem cell properties and that SOX2 has an important role in maintaining stem cell properties and functions that may be a potential target for effective lung cancer therapy.

GCC expression in lymph nodes (LNs) as a significant determinant of recurrence in stage II colon cancer (CC) patients (pts)

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Background: A multi-center prospectively specified retrospective study Validating Indicators to Associate Recurrence (VITAR) is assessing the relationship between guanylyl cyclase C (GCC) gene expression in formalin fixed LNs and recurrence risk in stage II CC pts not treated with adjuvant chemotherapy. Here we report the preplanned initial analysis performed with 241 pts.

Methods: GCC mRNA was quantified by RT-qPCR using FFPE LNs tissues from untreated stage II CC pts diagnosed from 1999-2006 with at least 10 LN examined blinded to clinical outcomes. Cox regression models examined the relationship between GCC nodal status and the prespecified primary endpoint of recurrence risk.

Results: Twenty-ninepts (12%) had a disease recurrence or cancer death, median follow-up was 60 months and median LNs examined was 15. The ratio of the number of GCC+ LNs over the total number of informative LNs (LNR) significantly predicted higher recurrence risk for 84 pts classified as high risk (HR, 2.38; p=0.02). The estimated 5-yr recurrence rates were 10% and 27% for the low and high risk group, respectively. After adjusting for age, T stage, number of LNs assessed, and MMR status, the significant association remained (HR, 2.61; 95% CI, 1.17-5.83; p=0.02). In a subset of 181 pts with negative margin, T3 tumor only and ≥12 LN examined, the GCC LNR had a HR for recurrence of 5.06 (95% CI 1.61-15.91, p=0.003), translating into 5-yr recurrence rates of 4% among low risk pts and 27% for the high-risk group.

Conclusions: Our results suggest that GCC expression in LNs is a significant determinant of recurrence in appropriately staged CC pts not treated with adjuvant chemotherapy. The validation component of the study is ongoing.

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Two or three year disease-free survival (DFS) as a primary end-point in stage III adjuvant colon cancer trials with fluoropyrimidines with or without oxaliplatin or irinotecan: data from 12,676 patients from MOSAIC, X-ACT, PETACC-3, C-06, C-07 and C89803

BACKGROUND

The ACCENT group previously established disease-free survival (DFS) with 2 or 3 years median follow-up to predict 5 year overall survival (5 year OS) in stage II and III colon cancer. ACCENT further proposed (1) a stronger association between DFS and OS in stage III than II, and (2) 6 or 7 years necessary to demonstrate DFS/OS surrogacy in recent trials. The relationship between end-points in trials with oral fluoropyrimidines, oxaliplatin and irinotecan is unknown.

METHODS

Associations between the treatment effect hazard ratios (HRs) on 2 and 3 years DFS, and 5 and 6 years OS were examined in 6 phase III trials not included in prior analyses from 1997 to 2002. Individual data for 12,676 patients were analysed; two trials each tested oxaliplatin, irinotecan and oral treatment versus 5-FU/LV.

FINDINGS

Overall association between 2/3 year DFS and 5/6 year OS HRs was modest to poor (simple R² measures: 0.58-0.76, model-based R²: 0.17-0.49). In stage III patients, the association increased (model-based R² ≥ 0.79). Observed treatment effects on 2 year DFS accurately 5/6 year OS effects overall and in stage III patients.

INTERPRETATION

In recent trials of cytotoxic chemotherapy, 2 or 3 years DFS HRs are highly predictive of 5 and 6 years OS HRs in stage III but not stage II patients. In all patients the DFS/OS association is stronger for 6 year OS, thus at least 6 year follow-up is recommended to assess OS benefit. These data support DFS as the primary end-point for stage III colon cancer trials testing cytotoxic agents.

Abstract PD08-05: Longitudinal Change of Pain and Other Symptoms in Breast Cancer Patients with Anastrozole Treatment

Background About one in three breast cancer patients undergoing treated with aromatase inhibitors report problems with joint pain, some times interfering with work and other activities. We conducted a longitudinal study to characterize the course and impact of arthralgia and other symptoms during anastozole therapy by following how pain and other symptoms change during anastrozole treatment, and the impact of symptoms on patient's functioning, health-related quality of life (HRQoL), and work productivity.

Methods Two cohorts of patients were included: Cohort I recruited patients at the start of anastrozole therapy: Cohort II recruited patients at the beginning of their third year of treatment. Brief Pain Inventory and MD Anderson Symptom Inventory were used to monthly assess patients’ pain, multiple symptoms, and functioning. A single item of quality of life question and the Work Productivity and Activity Impairment Questionnaire: General Health V2.0 were used to measure patient's HRQoL and impairment of working productivity every 6 months. A joint pain self-assessment kit was used to locate the affected joints. Statistical analyses were based on the one-year follow-up data and t-test, mixed effects models, linear regression models, and correlation coefficients were used.

Results At this point in the study, thirty-eight patients have finished the one year assessment in cohort I and 37 patients in cohort II. Cohort I patients reported no or mild pain and symptoms before they started therapy. Compared to baseline, pain ratings on 0 to 10 scales significantly increased at the 5th month (4.17±3.66 vs. 1.52±2.38, p=.015) and then decreased to baseline levels at the 9th month. Similarly, patients reported higher level of distress (3.5±3.63 vs. 1.00±2.07, p=.014) and hot flashes (4.0±4.57 vs. 1.45±2.36, p=.039) at month 5 and decreased to baselines levels at month 9. Mixed effects model with the total symptom interference as the dependent variable identified that among all symptoms, pain had the greatest impact on patient functioning (p<.0001). Patients with 4 or greater pain at month 5 reported poorer HRQoL at month 6 than those reported 3 or lower pain level (5.40±1.82 vs. 8.25±2.14, p=.020). Severity of pain at month 5 was positively correlated with working productivity: impairment at work (r=.80, p=.010), overall work productivity loss (r=.81, p=.014), and activity impairment (r=.84, p=.005). During the third year of anastrozole treatment, no symptom reaches the peak level at month 5 and no significant change was found over time, as well their HRQoL and working productivity. For cohort I patients, right knee was the most affected joint and right wrist as the most affected one for cohort II patients.

Conclusion Breast cancer patients beginning analstrozole therapy reported increased pain, distress, and hot flashes at the first year of treatment, worsening around the 5th month. Increased pain negatively impacted functioning, HRQoL, and work productivity. This study indicates that symptoms related to starting anastrozole develop over the first several months of therapy and have a functional impact on patients. Symptoms emerge when patients may be less actively followed clinically. Methods of managing these symptoms need to be investigated.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr PD08-05.

Proapoptotic Bid mediates the Atr-directed DNA damage response to replicative stress

Proapoptotic BH3 interacting domain death agonist (Bid), a BH3-only Bcl-2 family member, is situated at the interface between the DNA damage response and apoptosis, with roles in death receptor-induced apoptosis as well as cell cycle checkpoints following DNA damage.(1, 2, 3) In this study, we demonstrate that Bid functions at the level of the sensor complex in the Atm and Rad3-related (Atr)-directed DNA damage response. Bid is found with replication protein A (RPA) in nuclear foci and associates with the Atr/Atr-interacting protein (Atrip)/RPA complex following replicative stress. Furthermore, Bid-deficient cells show an impaired response to replicative stress manifest by reduced accumulation of Atr and Atrip on chromatin and at DNA damage foci, reduced recovery of DNA synthesis following replicative stress, and decreased checkpoint kinase 1 activation and RPA phosphorylation. These results establish a direct role for the BH3-only Bcl-2 family member, Bid, acting at the level of the damage sensor complex to amplify the Atr-directed cellular response to replicative DNA damage.

Effect of the ratios of diameter of silo to bead on the pressure screening in granular columns

We present the apparent mass measurements at the bottom of granular packings for different bead and silo sizes. The redirection parameter K in Janssen theory is found to increase with the ratios of the diameter of the silo to the bead. We attribute this feature to the friction between the beads and the confining wall of silo; it is the role of friction that leads to variations in the shielding of vertical stresses as well as pressure screening.