Putting sexuality (back) into HIV/AIDS: issues, theory and practice

After more than twenty years of programming and activism aimed at stemming the sexual transmission of HIV (and addressing the needs of those most vulnerable to infection) the HIV/AIDS epidemic continues to grow worldwide. Taking up this concern, this paper argues that one of the reasons why HIV prevention has had limited success is because of inadequate conceptualization of human sexuality in such work. Giving sexuality a more prominent position in responses to the epidemic raises a range of issues, including theorization of gender, understanding of sexual subjectivity, the significance of pleasure (or lack of pleasure) in sexual decision-making, and conceptualization of sexual behaviour and culture. Taking these themes forward entails asking significant questions about the underlying paradigmatic and methodological commitments of mainstream HIV/AIDS research, especially the tendency to reproduce accounts of human sexuality as if it were a measurable form of conduct only. Advocating new approaches that take the meaning and symbolic value of sexualities into account complicates established orthodoxies in the field whilst offering potential for more effective HIV prevention strategies.

Factors influencing family physicians' drug prescribing behaviour in asthma management in primary care

INTRODUCTION

Little is known about the decision pathway that family physicians (FP) take in considering drug therapy for their asthma patients. This study aimed to explore the factors that influence FPs' decisions in prescribing medications for their asthma patients.

METHODS

A qualitative method using focus group discussions (FGD) was used to gather qualitative data based on a semi-structured topic guide from FPs of different training backgrounds and practices. 29 Singapore FPs working as private general practitioners (GP), polyclinic doctors and locums were recruited into five FGDs.

RESULTS

The FPs' asthma drug prescription decisions were related to the FPs' medical training and acquisition of asthma-related information and updates. Uncertainty of disease diagnosis, patients' beliefs and their perceptions of the disease and treatment, as well as the FPs' concerns about drug side effects, were significant considerations for the participants. Costs related to differential subsidies in the consultation fees and drugs between public polyclinics and GP clinics in the local primary healthcare system, was a key factor in influencing the FPs' asthma drug treatment decisions.

CONCLUSION

FPs' asthma drug prescribing behaviour is influenced by their medical training, disease definition, patient factors and drug costs in the context of the local primary healthcare system and policy.

A qualitative study of factors influencing family physicians' prescription of the Written Asthma Action Plan in primary care in Singapore

INTRODUCTION

The Written Asthma Action Plan (WAAP) educates patients on the early recognition and treatment of deteriorating asthma. It has been adopted in Singapore polyclinics and restructured hospitals in the past few years as recommended by the Singapore National Asthma Programme. Local asthma patients can choose to be treated by family physicians at public polyclinics or by private general practitioners (GPs). In a previous study, half of the physicians in primary care self-reported that they formulated an asthma action plan for their patients, but little is known about their actual practices. This qualitative study explored family physicians' views of WAAP and its implementation in primary care in Singapore.

METHODS

Qualitative data was obtained for 29 participants from polyclinics, GP clinics or locum doctors at five separate focus group discussions. The data was coded using NVivo-7 software, audited and analysed to identify emergent themes.

RESULTS

The participants generally perceived the usefulness of WAAP. While WAAP was widely used in polyclinics, GPs rarely used it. Even in polyclinics, usage varied and was associated with participants' training and practice of WAAP and task substitution to nurses. They perceived that WAAP would benefit only selected motivated patients who could understand and use it. They were hampered by language barriers in educating their multiracial patients and the perceived lack of time related to patient loads in polyclinics. The GPs lacked training and practice, role models and relied on verbal instructions as a personalised form of care delivery.

CONCLUSION

Family physicians generally perceived WAAP as useful, but implementation was hampered by lack of training and practice, language barriers and perceived benefits for patients.

A retrospective study of drug response indicator test (DRIT) as a predictive test for therapeutic treatment outcomes of advanced breast cancer patients (ABC)

Abstract #6075

We conducted a retrospective study of DRIT, an investigational diagnostic test to predict chemotherapy and endocrine therapy treatment outcomes in ABC. DRIT is a quantitative measurement of Drug Response Indicator (DRI) expression levels in formalin fixed, paraffin embedded tumor tissue. DRI chosen for each drug is related to the perceived mechanism of action of the drug. The quantitative measurement of DRI expression in the tumor tissue is based on the fluorescent dye-labeled monoclonal antibody (mAb) staining, followed by acquisition of digital images using computer-assisted microscopy, calibrated to an external standard. DRI expression measurement results in classification of the tumor as sensitive or resistant to a particular drug based on our in vitro studies of drug sensitivity/resistance in cell lines. If a tumor is classified as sensitive to a drug/s by DRIT, this predicts that the patient (Pt) will respond to treatment, while if a tumor is classified as resistant this predicts that the Pt will not respond to the drug/s therapy. Clinically the treatment outcome is classified into a responsive group (non-progressive disease,CR, PR, SD) & a non-responsive group (progressive disease, PD). The drugs & DRI tested are: capcitabine/thymidylate synthase; Taxanes /β-tubulin isoform III, trastuzamab/HER-2, Endocrine therapy/estrogen receptor, gemcitabine/ribonucleotide reductase. 51 ABC received mono or doublet therapy as first 3 lines of therapy-(80 treatments). The percent accuracy (number of accurate predictions/number of treatment interventions) for monotherapy is 87% (61/70), 100% (10/10) for doublet therapy and 89% (71/80) for all treatments. The accuracy of prediction for responsive patients is 86% (60/69) and 100% (11/11) for non responsive patients. DRIT diagnostic performance for 80 treatment outcome predictions for endocrine therapy and mono and doublet chemotherapy is as follows: sensitivity 1.00, specificity 0.55, positive predictive value 0.87, negative predictive value 1.00, and overall accuracy 0.88. For the standard of care outcomes, the favorable response rate for the 80 treatments is 75% (60/80), the potential favorable response rate with DRIT input is 86% (60/69) with 11 ineffective treatments identified by DRIT accurately 100% (11/11). Thus, DRIT input can identify effective (86%) & ineffective (100%) treatments in this cohort of ABC patients. DRIT is under developement as a diagnostic test to predict treatment outcomes prior to the selection of a particular drug for anticancer therapy, so that the most effective drug can be prescribed for an individual cancer patient. This retrospective study in ABC patients shows that DRIT has a potential to be a useful test to predict treatment outcomes.
 Supported in part by Maryland Industry Partnership Program – MIPS.

Citation Information: Cancer Res 2009;69(2 Suppl):Abstract nr 6075.

Improving head growth in preterm infants--a randomised controlled trial II: MRI and developmental outcomes in the first year

BACKGROUND

Very preterm infants are at risk of poor growth and neurodevelopmental outcome. Illness and difficulties overcoming the challenges of feeding these infants often lead to undernutrition in the first few weeks.

OBJECTIVE

To explore the relationships between early nutrition, post-natal head growth, quantitative magnetic resonance imaging (MRI) and developmental outcome in the first year among infants born before 29 weeks' gestation.

DESIGN

Infants born before 29 weeks' gestation were randomised to receive hyperalimented or standard feeding regimen from birth to 34 weeks' postmenstrual age (PMA). The primary outcome was occipitofrontal circumference (OFC) at 36 weeks' OFC. Quantitative MRI was performed at 40 weeks' PMA. Developmental assessment using Bayley Scales of Infant Development II (BSID II) was carried out at 3 and 9 months post-term.

RESULTS

109 infants survived to the end of the first year PMA. 65 infants underwent MRI scan. 81 and 71 infants were seen at 3 and 9 months post-term. Quantitative MRI findings, mental development index (MDI) and psychomotor development index (PDI) were not statistically different between the two groups. Total brain volume (TBV) at 40 weeks' PMA, MDI and PDI at 3 months post-term correlated significantly with energy deficit at 28 days of age

CONCLUSIONS

Improving early energy deficit in very preterm infants may promote brain growth. Quantitative MRI may have a role to play in predicting developmental outcome. Post-natal growth at 36 weeks' PMA and quantitative MRI finding at 40 weeks' PMA appear to be closely related to mental outcomes in the first year.

TRIAL REGISTRATION NUMBER

ISRCTN 19509258.

Magnetic resonance direct thrombus imaging of the evolution of acute deep vein thrombosis of the leg

BACKGROUND

Accurate diagnosis of acute recurrent deep vein thrombosis (DVT) is relevant to avoid improper diagnosis and unnecessary life-long anticoagulant treatment. Compression ultrasound has high accuracy for a first episode of DVT, but is often unreliable in suspected recurrent disease. Magnetic resonance direct thrombus imaging (MR DTI) has been shown to accurately detect acute DVT. The purpose of this prospective study was to determine the MR signal change during 6 months follow-up in patients with acute DVT.

PATIENTS/METHODS

This study was a prospective study of 43 consecutive patients with a first episode of acute DVT demonstrated by compression ultrasound. All patients underwent MR DTI. Follow-up was performed with MR-DTI and compression ultrasound at 3 and 6 months respectively. All data were coded, stored and assessed by two blinded observers.

RESULTS

MR direct thrombus imaging identified acute DVT in 41 of 43 patients (sensitivity 95%). There was no abnormal MR-signal in controls, or in the contralateral extremity of patients with DVT (specificity 100%). In none of the 39 patients available at 6 months follow-up was the abnormal MR-signal at the initial acute DVT observed, whereas in 12 of these patients (30.8%) compression ultrasound was still abnormal.

CONCLUSION

Magnetic resonance direct thrombus imaging normalizes over a period of 6 months in all patients with diagnosed DVT, while compression ultrasound remains abnormal in a third of these patients. MR-DTI may potentially allow for accurate detection in patients with acute suspected recurrent DVT, and this should be studied prospectively.

SAG/ROC2/RBX2 is a HIF-1 target gene that promotes HIF-1 alpha ubiquitination and degradation

SAG (sensitive to apoptosis gene) or ROC2/RBX2 is the second family member of ROC1/RBX1, a component of SCF (Skp1, Cullin, F-box protein) and VCB (von Hippel-Lindau (VHL), Cullin and Elongin B/C) E3 ubiquitin ligases. SAG protected cells from hypoxia-induced apoptosis when overexpressed. We report here that SAG was subjected to hypoxia induction at the levels of mRNA and protein. Hypoxia induction of SAG was largely HIF-1alpha dependent. A consensus HIF-1-binding site, GCGTG was identified in the first intron of the SAG gene. In response to hypoxia, HIF-1 bound to this site and transactivated SAG expression. SAG transactivation required both the intact binding site in cis and HIF-1alpha in trans. On the other hand, like its family member, ROC1, SAG promoted VHL-mediated HIF-1alpha ubiquitination and degradation, which was significantly inhibited upon small interfering RNA silencing of SAG or ROC1. Furthermore, the endogenous HIF-1alpha at both basal and hypoxia-induced levels was significantly increased upon SAG silencing. Finally, SAG forms in vivo complex with Cul-5 and VHL under hypoxia condition. These results suggest an HIF-1-SAG feedback loop in response to hypoxia, as follows: hypoxia induces HIF-1 to transactivate SAG. Induced SAG then promotes HIF-1alpha ubiquitination and degradation. This feedback loop may serve as a cellular defensive mechanism to reduce potential cytotoxic effects of prolonged HIF-1 activation under hypoxia.

Death on the kidney waiting list--good candidates or not?

The waiting list for a kidney or simultaneous pancreas-kidney transplant is growing, and waiting times are getting longer. As a consequence, transplant candidates are dying while waiting for a transplant. In a retrospective analysis, we studied whether patients on our list who died while waiting were good candidates. From January 1, 2002, through September 30, 2004, 85 candidates on our list died. Of these, 71% were waiting for a first transplant; 62% had a current panel-reactive antibody (PRA) level of 0%. Of the 85 candidates who died, the mean (+/-SD) age was 53 +/- 11 years; mean waiting time from listing to death, 979 +/- 749 days. The most common cause of death was cardiovascular disease. Many of those candidates who died while waiting were young, first-transplant candidates with a low PRA level. But only limited information was available; prospective studies are necessary to determine whether or not they were, in fact, good candidates.

Mobilized retrotransposon Tos17 of rice by alien DNA introgression transposes into genes and causes structural and methylation alterations of a flanking genomic region

Tos17 is a copia-like endogenous retrotransposon of rice, which can be activated by various stresses such as tissue culture and alien DNA introgression. To confirm element mobilization by introgression and to study possible structural and epigenetic effects of Tos17 insertion on its target sequences, we isolated all flanking regions of Tos17 in an introgressed rice line (Tong35) that contains minute amount of genomic DNA from wild rice (Zizania latifolia). It was found that there has been apparent but limited mobilization of Tos17 in this introgression line, as being reflected by increased but stable copy number of the element in progeny of the line. Three of the five activated copies of the element have transposed into genes. Based on sequence analysis and Southern blot hybridization with several double-enzyme digests, no structural change in Tos17 could be inferred in the introgression line. Cytosine methylation status at all seven CCGG sites within Tos17 was also identical between the introgression line and its rice parent (Matsumae)-all sites being heavily methylated. In contrast, changes in structure and cytosine methylation patterns were detected in one of the three low-copy genomic regions that flank newly transposed Tos17, and all changes are stably inherited through selfed generations.

Serial monitoring for circulating cancer cells in blood samples of stage 1–4 breast cancer patients

623

Serial monitoring for presence, number & characterization of circulating cancer cells (CCC) may provide valuable information that may be relevant to prognosis and treatment outcomes of breast cancer patients (BCP). We conducted a serial blood sampling study at the University of Maryland in BCP with stage 1–4 breast carcinoma. 15–20 ml of venous blood were collected before the start of systemic therapy and periodically thereafter & processed using negative selection method with double-gradient centrifugation & magnetic cell sorting to remove WBCs. Digital images of FITC-positive epithelial cells were acquired with a fluorescence microscope & counted. CCC from 41 patients (Pts) were also stained with Trastuzu-mAb-532 to quantify the HER-2/neu cell surface receptor expression relative to a fluorescence standard. 105 Pts were accrued & 415 blood samples tested (median number of samples/pt; 4 (1–8). During the 24 mos. monitoring period CCC were detected in 57 of 105 pts (54%). The Table below shows that presence of >10 CCC/sample is associated with decreased survival and increased probability of having metastatic disease.(Exact chi-square test for presence vs. absence of metastatses in A, B, C, D groups, P < 0.0001; Fisher’s exact test to compare individual groups: for B vs C+ D, P < 0.001; B vs C, P=0.001). HER-2/neu expression was assessed in CCC of 25 pts (minimum of 4 CCC per sample) as compared with strongly HER-2/neu positive control cell line SKBR-3. 10 Pts were positive & 15 negative for HER-2/neu over-expression in CCC. CCC data & primary tumor data concurred in 6 of 7 Her-2/neu primary tumor tissue positive Pts & in 12 of 13 Her-2/neu primary tissue negative Pts. For 5 Pts tissue data was not available. Conclusions: Increasing CCC numbers/sample appear to correlate with adverse outcome of BCP. Our CCC Test may provide valuable information about prognosis of stage 1–4 BCP. HER-2/neu expression could be quantified in individual CCC & concurred with primary tumor data in 90% of Pts. Supported by NCI Grant CA081903

[Table: see text]

[Table: see text]

Gene expression profiling identifies two distinct papillary renal cell carcinoma (RCC) subgroups of contrasting prognosis

4503

Background: Despite the moderate incidence of papillary renal cell carcinoma (PRCC), there is a disproportionately limited understanding of its underlying genetic programs. There is no effective therapy for metastatic PRCC, and patients are often excluded from kidney cancer trials. A morphological classification of PRCC into Type 1 and Type 2 tumors has been recently proposed, but its biological relevance remains uncertain. Methods: We studied the gene expression profiles of 34 cases of PRCC using Affymetrix HGU133 Plus 2.0 arrays (54,675 probe sets) using both unsupervised and supervised analysis. Comparative genomic microarray analysis (CGMA) was used to infer cytogenetic aberrations, and pathways were ranked with a curated database. Expression of selected genes was validated by immunohistochemistry in 34 samples, with 15 independent tumors. Results: We identified two highly distinct molecular PRCC subclasses with morphologic correlation. The first class, with excellent survival, corresponded to three histological subtypes: Type 1, low-grade Type 2 and mixed Type 1/low-grade Type 2 tumors. The second class, with poor survival, corresponded to high-grade Type 2 tumors (n = 11). Dysregulation of G1/S and G2/M checkpoint genes were found in Class 1 and Class 2 tumors respectively, alongside characteristic chromosomal aberrations. We identified a 7-transcript predictor that classified samples on cross-validation with 97% accuracy. Immunohistochemistry confirmed high expression of cytokeratin 7 in Class 1 tumors, and of topoisomerase IIα in Class 2 tumors. Conclusions: We report two molecular subclasses of PRCC, which are biologically and clinically distinct, which may be readily distinguished in a clinical setting. This may also have therapeutic implications.

No significant financial relationships to disclose.

The von Hippel-Lindau gene mutation is associated with the good-prognosis profiling subtype of clear cell renal cell carcinoma

4532

Background: The prevalence of von Hippel-Lindau (VHL) mutations in clear cell renal cell carcinoma (ccRCC) is about 30–50%. The association between VHL mutation and patient prognosis remains controversial, despite extensive in vitro research on its role in hypoxia response. We have previously reported a robust prognostic classification of ccRCC using gene expression profiling. In view of reports of activity of anti-angiogenesis agents, we studied the association of VHL mutation with tumor profiling subtypes, survival and other clinical parameters. Methods: All exons of the VHL gene in 88 ccRCC samples were sequenced. Expression profiling using oligonucleotide arrays (54,675 probe sets) was also performed, and the samples classified using hierarchical clustering. For identification of VHL mutation specific signatures, nearest shrunken centroids with internal validation was used with a 10% misclassification cutoff. Results: 35% of the samples had VHL mutations. Mutation status was not significantly associated with survival on univariate analysis (p = 0.54). Hierarchical clustering yielded two ccRCC subtypes with divergent clinical outcomes (HR = 4.13, p < 0.001). VHL mutations were significantly associated with the good-prognosis profiling subtype of ccRCC tumors (OR 3.3, p = 0.04), but no effect modification between VHL mutation and the prognostic subtypes was found (p=0.31). No standard clinical parameter was associated with VHL mutation. No significant association between VHL mutation and downstream hypoxia response gene expression, including VEGF (p = 0.14), PDGF (p = 0.5), TGF-A (p = 0.24) and GLUT1 (p = 0.45) was found. Conclusion: While VHL mutation is associated with a biologically distinct good-prognosis profiling tumor subtype, its lack of prognostic value on univariate analysis suggests an expanded study to evaluate effect modification. The absence of a specific gene classifier for VHL mutation and the lack of association between VHL gene mutation and known hypoxia response genes suggest that VHL mutations result in heterogenous tissue phenotypes. These results support molecular subtyping of ccRCC in laboratory and clinical studies; in particular, this may be critical for trials involving anti-angiogenesis agents.

No significant financial relationships to disclose.

Autologous stem cell transplantation followed by consolidation chemotherapy for patients with multiple myeloma

Although high-dose therapy and autologous stem cell transplant (ASCT) is superior to conventional chemotherapy for treatment of myeloma, most patients relapse and the time to relapse depends upon the initial prognostic factors. The administration of non-cross-resistant chemotherapies during the post-transplant period may delay or prevent relapse. We prospectively studied the role of consolidation chemotherapy (CC) after single autologous peripheral blood stem cell transplant (auto-PBSCT) in 103 mostly newly diagnosed myeloma patients (67 patients were < or =6 months from the initial treatment). Patients received conditioning with BCNU, melphalan+/-gemcitabine and auto-PBSCT followed by two cycles of the DCEP+/-G regimen (dexamethasone, cyclophosphamide, etoposide, cisplatin+/-gemcitabine) at 3 and 9 months post-transplant and alternating with two cycles of DPP regimen (dexamethasone, cisplatin, paclitaxel) at 6 and 12 months post-transplant. With a median follow-up of 61.2 months, the median event-free survival (EFS) and overall survival (OS) are 26 and 54.1 months, respectively. The 5-year EFS and OS are 23.1 and 42.5%, respectively. Overall, 51 (49.5%) patients finished all CC, suggesting that a major limitation of this approach is an inability to deliver all planned treatments. In order to improve results following autotransplantation, novel agents or immunologic approaches should be studied in the post-transplant setting.

Upregulation and activation of PKC alpha by ErbB2 through Src promotes breast cancer cell invasion that can be blocked by combined treatment with PKC alpha and Src inhibitors

Although ErbB2 is known to enhance breast cancer metastasis, the signaling events responsible for this remain elusive. Alpha-isozyme of protein kinase C (PKCalpha), which is involved in cancer development and progression, has been suggested to be activated by ErbB2 without direct evidence. In addition, the roles of PKCalpha in ErbB2-mediated cancer cell malignancy have not been clearly identified. In this study, we investigated whether ErbB2 can activate PKCalpha and determined what role PKCalpha plays in ErbB2-mediated breast cancer cell invasion. We expressed wild-type and mutant ErbB2 with altered signaling capacities in MDA-MB-435 breast cancer cells and revealed that overexpression or activation of ErbB2 in MDA-MB-435 cells upregulated and activated PKCalpha and that downregulation of ErbB2 by small-interfering RNA decreased the expression and activity of PKCalpha in BT474 breast cancer cells. These in vitro results were supported by data from breast cancer patient samples. In 150 breast cancer tumor samples, ErbB2-overexpressing tumors showed significantly higher positive rates of PKCalpha membrane immunohistochemistry staining than that of ErbB2-low-expressing tumors. Mechanistically, we found that PKCalpha is co-immunoprecipitated with Src and PKCalpha expression and activity can be decreased by Src inhibitor PP2 and by the expression of a dominant-negative mutant of Src. Moreover, ErbB2-mediated upregulation of urokinase-type plasminogen activator receptor (uPAR) is reduced by either the PKCalpha inhibitor Go6976 or the Src inhibitor PP2, and the combination of Go6976 with PP2 is superior to either agent alone in suppressing uPAR expression and cell invasion. These results demonstrate that PKCalpha is critical for ErbB2-mediated cancer cell invasion and provide valuable insights for current and future PKCalpha and Src inhibitor clinical trials.