Scaling of the F2 structure function in nuclei and quark distributions at x>1

We present new data on electron scattering from a range of nuclei taken in Hall C at Jefferson Lab. For heavy nuclei, we observe a rapid falloff in the cross section for x>1, which is sensitive to short-range contributions to the nuclear wave function, and in deep inelastic scattering corresponds to probing extremely high momentum quarks. This result agrees with higher energy muon scattering measurements, but is in sharp contrast to neutrino scattering measurements which suggested a dramatic enhancement in the distribution of the "superfast" quarks probed at x>1. The falloff at x>1 is noticeably stronger in 2H and 3He, but nearly identical for all heavier nuclei.

Probing quark-gluon interactions with transverse polarized scattering

We have extracted QCD matrix elements from our data on doubly polarized inelastic scattering of electrons on nuclei. We find the higher twist matrix element d˜2, which arises strictly from quark-gluon interactions, to be unambiguously nonzero. The data also reveal an isospin dependence of higher twist effects if we assume that the Burkhardt-Cottingham sum rule is valid. The fundamental Bjorken sum rule obtained from the a0 matrix element is satisfied at our low momentum transfer.

Polarization transfer in the 4He(e,e'p)3H reaction at Q2=0.8 and 1.3 (GeV/c)2

Proton recoil polarization was measured in the quasielastic 4He(e,e'p)3H reaction at Q{2}=0.8 and 1.3  (GeV/c){2} with unprecedented precision. The polarization-transfer coefficients are found to differ from those of the 1H(e,e'p) reaction, contradicting a relativistic distorted-wave approximation and favoring either the inclusion of medium-modified proton form factors predicted by the quark-meson coupling model or a spin-dependent charge-exchange final-state interaction. For the first time, the polarization-transfer ratio is studied as a function of the virtuality of the proton.

Human lactoferrin stimulates skin keratinocyte function and wound re-epithelialization

BACKGROUND

Human lactoferrin (hLF), a member of the transferrin family, is known for its antimicrobial and anti-inflammatory effects. Recent studies on various nonskin cell lines indicate that hLF may have a stimulatory effect on cell proliferation.

OBJECTIVES

To study the potential role of hLF in wound re-epithelialization.

MATERIALS AND METHODS

The effects of hLF on cell growth, migration, attachment and survival were assessed, with a rice-derived recombinant hLF (holo-rhLF), using proliferation analysis, scratch migration assay, calcein-AM/propidium iodide staining and terminal deoxynucleotidyl transferase-mediated dUTP nick-end labelling (TUNEL) method, respectively. The mechanisms of hLF on cell proliferation and migration were explored using specific pathway inhibitors. The involvement of lactoferrin receptor low-density lipoprotein receptor-related protein 1 (LRP1) was examined with RNA interference technique. An in vivo swine second-degree burn wound model was also used to assess wound re-epithelialization.

RESULTS

Studies revealed that holo-rhLF significantly stimulated keratinocyte proliferation which could be blocked by mitogen-activated protein kinase (MAPK) kinase 1 inhibitor. Holo-rhLF also showed strong promoting effects on keratinocyte migration, which could be blocked by either inhibition of the MAPK, Src and Rho/ROCK pathways, or downregulation of the LRP1 receptor. With cells under starving or 12-O-tetradecanoylphorbol-13-acetate exposure, the addition of holo-rhLF was found greatly to increase cell viability and inhibit cell apoptosis. Additionally, holo-rhLF significantly increased the rate of wound re-epithelialization in swine second-degree burn wounds.

CONCLUSIONS

Our studies demonstrate the direct effects of holo-rhLF on wound re-epithelialization including the enhancement of keratinocyte proliferation and migration as well as the protection of cells from apoptosis. The data strongly indicate its potential therapeutic applications in wound healing.

Complexity and accuracy of image registration methods in SPECT-guided radiation therapy

The use of functional imaging in radiotherapy treatment (RT) planning requires accurate co-registration of functional imaging scans to CT scans. We evaluated six methods of image registration for use in SPECT-guided radiotherapy treatment planning. Methods varied in complexity from 3D affine transform based on control points to diffeomorphic demons and level set non-rigid registration. Ten lung cancer patients underwent perfusion SPECT-scans prior to their radiotherapy. CT images from a hybrid SPECT/CT scanner were registered to a planning CT, and then the same transformation was applied to the SPECT images. According to registration evaluation measures computed based on the intensity difference between the registered CT images or based on target registration error, non-rigid registrations provided a higher degree of accuracy than rigid methods. However, due to the irregularities in some of the obtained deformation fields, warping the SPECT using these fields may result in unacceptable changes to the SPECT intensity distribution that would preclude use in RT planning. Moreover, the differences between intensity histograms in the original and registered SPECT image sets were the largest for diffeomorphic demons and level set methods. In conclusion, the use of intensity-based validation measures alone is not sufficient for SPECT/CT registration for RTTP. It was also found that the proper evaluation of image registration requires the use of several accuracy metrics.

Obstructed small bowel ruptured toward the inguinal canal resulting from metastatic colon carcinoma in an irreducible, recurrent inguinal hernia with mesh-plug repair: Report of a case

Four years after treatment of colon cancer an 82-year-old man presented with an irreducible, recurrent inguinal hernia with mesh-plug repair. Delayed surgical exploration revealed metastatic cancer with small bowel adhesion to the mesh-plug and perforation. The mesh-plug with adherent tissue was removed through the inguinal incision, and the ruptured small bowel was resected. Histopathology revealed moderately differentiated mucinous adenocarcinoma of the tissue adhering to the prosthetic material corresponding to the original colon cancer.

Aflatoxin-albumin adducts and correlation with decreased serum levels of vitamins A and E in an adult Ghanaian population

A study of aflatoxin (AF) exposure and the levels of vitamins A and E was carried out with a group of 507 Ghanaian participants. AFB(1)-albumin adducts (AFB-AA) were measured by radioimmunoassay and vitamins A and E were measured by high-performance liquid chromatography (HPLC). The average level of serum AFB-AA was 0.94 +/- 0.64 (range = 0.1-4.44) pmol mg(-1) albumin. Mean levels of vitamins A and E were 1.32 +/- 0.48 (range = 0.41-4.85) micromol l(-1) and 15.68 +/- 4.12 (range = 6.35-30.40) micromol l(-1), respectively. A significantly negative correlation was found between serum AFB-AA and vitamin A levels (r = -0.110, p = 0.013). An even stronger, significant negative, correlation was found between serum AFB-AA and vitamin E levels (r = -0.149, p < 0.001). Serum AFB-AA levels were statistically higher (median = 0.985 pmol mg(-1) albumin) in subjects who had low levels of both vitamins A and E as compared with the levels (median = 0.741 pmol mg(-1) albumin) subjects who had high vitamins A and E levels (p(trend) = 0.001). To verify these findings, blood samples were again collected from 165 of the 507 people 3 months after the initial collection. Significantly negative correlations were confirmed between levels of serum AFB-AA and both vitamins A (r = -0.232, p = 0.003) and E (r = -0.178, p = 0.023). Again, high serum AFB-AA concentrations (median = 1.578 pmol mg(-1) albumin) were found in subjects with low levels of vitamins A and E compared with the concentrations (median = 1.381 pmol mg(-1) albumin) in subjects with high levels of vitamins A and E (p(trend) = 0.002). These data show that AF exposure was associated with decreased levels of serum vitamins A and E in high-risk human populations, which may significantly influence the incidence of AF-related adverse health effects.

Coexpression and Synergistic Role of Multiple Atypical Chemokine Binders in Breast Cancer

Background: The expression and role of Duffy antigen receptor for chemokine (DARC), D6 and ChemoCentryx chemokine receptor (CCX-CKR) in breast cancer have already been studied independently in the past several years. However, the relationship and importance of these atypical chemokine binders (ACB) are still unclear. In this large scale clinical study, we invastigated the characteristics of multiple ACB simultaneously. Material and Methods: The protein levels of DARC, D6 and CCX-CKR were analyzed by immunohistochemistry in 517 patients with invasive breast cancer, 29 patients with noninvasive breast cancer. All of these cases come from the Cancer Hospital of Fudan University during 2001-2006, with complete clinicopathological data and follow-up data, including survival information. Results: In the invasive breast cancer patients, triple, double and single positive expression of these ACB were 135 cases (26.1%), 154 cases (29.8%) and 121 cases (23.4%), respectively. On the other hand, 107 cases (20.7%) were complete negative. The triple positive staining was significantly conversely correlated with lymph node metastasis, disease stage, relapse-free survival (RFS) as well as overall survival (OS). DARC, D6, and CCX-CKR were independent factors that influenced lymph node metastasis and their coexpression was favorable prognostic factor for RFS and OS. Discussion: Our results confirmed that DARC, D6, and CCX-CKR play a negative role in breast cancer. Furthermore, their triple or double high coexpression is more favorable for the patients, suggesting that multiple ACB may provide better protection against metastasis and relapse by synergistically regulating chemokine network in breast cancer.

Citation Information: Cancer Res 2009;69(24 Suppl):Abstract nr 4166.

Different pathways are involved in arsenic-trioxide-induced cell proliferation and growth inhibition in human keratinocytes

BACKGROUND

Arsenic is a carcinogen that is associated with an increased risk of human skin cancer. On the other hand, arsenic trioxide (As(2)O(3)) has potential anticancer activity against a wide range of carcinomas. The mechanisms involved in these two opposing processes remain unclear.

METHODS

We used normal human keratinocytes (NHK), the human keratinocyte HaCaT cell line and human epidermal carcinoma cells (A431 cell line) to investigate potential pathways involved in the effects on cell proliferation and growth inhibition by different concentrations of As(2)O(3).

RESULTS

At low concentrations (0.5-32 nM), As(2)O(3) enhanced keratinocyte proliferation and regulated the expression of about 172 genes. Among them, cell cycling pathway genes (including CDK4 and E2F1) were significantly upregulated. At high concentrations (0.5-10 microM), As(2)O(3) inhibited cell growth in NHK and HaCaT cells, but not in A431 cells. As(2)O(3) significantly induced NHK and HaCaT apoptosis through the activation of caspase-3, as well as cell cycle arrest at the G2-M phase.

CONCLUSION

Our data suggest that different pathways are involved in As(2)O(3)-mediated proliferation and growth inhibition. In addition, skin carcinoma cells were resistant to As(2)O(3)-induced cell growth inhibition and apoptosis when compared to NHK and HaCaT cells. Therefore, As(2)O(3) may not be appropriate for treatment of skin carcinomas.

New measurements of the European Muon Collaboration effect in very light nuclei

New Jefferson Lab data are presented on the nuclear dependence of the inclusive cross section from (2)H, (3)He, (4)He, (9)Be and (12)C for 0.3 < x < 0.9, Q(2) approximately 3-6 GeV(2). These data represent the first measurement of the EMC effect for (3)He at large x and a significant improvement for (4)He. The data do not support previous A-dependent or density-dependent fits to the EMC effect and suggest that the nuclear dependence of the quark distributions may depend on the local nuclear environment.

Clinical features of ileal pouch-anal anastomosis in African American patients with underlying ulcerative colitis

BACKGROUND

The prevalence of inflammatory bowel disease in African Americans appears to be increasing. The data on differences in disease behavior and severity between the races have been conflicting.

AIM

To evaluate the effect of race on outcome and natural history of patients with ileal pouch-anal anastomosis.

METHODS

All African American patients with underlying ulcerative colitis and ileal pouch-anal anastomosis who were seen in our subspecialty Pouchitis Clinic from 2002 to 2008 were included. The control group consisted of Caucasian patients with ulcerative colitis and ileal pouch-anal anastomosis who were randomly selected from the same Pouch Registry at a ratio of 4:1. We compared pouch failure, Crohn's disease of the pouch, and chronic pouchitis rates, as well as other 23 demographic and clinical variables between African American and Caucasian patients.

RESULTS

A total of 12 African American patients and 48 Caucasian patients were evaluated in this case-control study. There were no significant differences in the frequency of pouch failure, Crohn's disease of the pouch, or chronic pouchitis between the African American and Caucasian groups. However, African American patients were found to have a significantly shorter duration of inflammatory bowel disease (11.5 years vs. 17.0 years, P = 0.024) as well as significantly shorter duration of pouch (1.5 years vs. 4 years, P = 0.02). African Americans were also less likely to have pancolitis at the time of colectomy (83% vs. 100%, P = 0.037).

CONCLUSIONS

While there were no significant differences in pouch outcomes between the races, African American patients appeared to have more left-sided colitis at the time of colectomy, with a shorter duration of inflammatory bowel and ileal pouch. This finding suggests that the natural history of ulcerative colitis and disease course before and after restorative proctocolectomy may be different between these racial groups.

Distribution of pathogenic Yersinia enterocolitica in China

Yersinia enterocolitica (1,295 strains) was isolated from diarrhea patients, livestock, poultry, wild animals, insect vectors, food, and the environment. They were studied for epidemiology distribution using bacterial biochemical metabolism tests, their virulence genes, and pulsed-field gel electrophoresis (PFGE) sub-typing. The data showed that 416 of the 1,295 strains were pathogenic, where the pathogenic Chinese isolates were of serotypes O:3 and O:9. These two serotypes were found in livestock and poultry, with swine serving as the major reservoir. The geographic distribution of pathogenic isolates was significantly different, where most of the strains were isolated from the cold northern areas, whereas some serotype O:3 strains were recovered from the warm southern areas. By the analysis of the data of the Ningxia Hui Autonomous Region, we find the phenomenon of 'concentric circle distribution' around animal reservoirs and human habitation. The clustering of PFGE showed that the patterns of the pathogenic strains isolated from diarrhea patients were identical compared to those from the animals in the same area, thus, suggesting that the human infection originated from the animals.

Assessment of two dosing schedules of GSK1363089 (GSK089), a dual MET/VEGFR2 inhibitor, in metastatic gastric cancer (GC): Interim results of a multicenter phase II study

4502

Background: GSK089 is an oral, small-molecule inhibitor of cMET and VEGFR2/KDR, and has potent antitumor activity in cMET-amplified cell lines and xenografts. cMET is reportedly amplified, overexpressed and/or activated in GC, making it an attractive therapeutic target. This phase II study examines the safety and efficacy of 2 dosing schedules of GSK089 as a single agent in patients (pts) with metastatic GC. Methods: Pts with distal esophagus, GE junction or stomach adenocarcinoma, 0–2 prior chemotherapy regimens, adequate organ function, measurable disease, and ECOG PS 0–2 are sequentially enrolled in 2 cohorts: 1) Intermittent 5 days on/9 off - GSK089 240 mg/d on D1–5 repeated every 14 days, and 2) Daily - 80 mg/d. Primary study endpoint (response) is assessed every 8 weeks. cMET amplification by FISH (≥2 copies of cMET per copy of chromosome 7) is not an entry criterion, but is determined on archival tissue for all pts. Pre- and on-treatment tumor biopsies in select pts and plasma samples in all pts are analyzed for GSK089 effects on direct and downstream drug targets. GSK089 pharmacokinetics (PK) are also evaluated. Results: As of 12/19/08, enrollment to the 5 on/9 off cohort is complete with 41 evaluable pts, and 14 evaluable pts have enrolled on the daily cohort. cMET amplification was seen in 3/43 (7%) pts tested; all 3 were in 5 on/9 off cohort. Best response of stable disease (SD), was noted in 6/41 (15%) pts in the 5 on/9 off cohort (none were cMET-amplified), with 2 pts SD >6 months, 1 ongoing; and in 3/14 (21%) pts in the daily cohort. Among all-enrolled pts (48 pts in 5 on/9 off, 16 pts in daily cohort), LFT abnormalities (9%), fatigue (5%), and venous thromboembolism (3%) were the most common GSK089 related grade 3- 4 adverse events (AE). Only 1 possibly related grade 5 AE, death due to unknown cause, was noted. Conclusions: GSK089 is well tolerated on both dosing schedules. cMET amplification in metastatic GC is rare. Single agent GSK089 demonstrates minimal antitumor activity in a cMET-unselected gastric population on the 5 on/9 off schedule. Enrollment on the daily dosing schedule continues, now with mandatory pre- and on-treatment biopsies to better define cMET pathway and target inhibition with GSK089.

No significant financial relationships to disclose.