The MURAL collection of prostate cancer patient-derived xenografts enables discovery through preclinical models of uro-oncology

Preclinical testing is a crucial step in evaluating cancer therapeutics. We aimed to establish a significant resource of patient-derived xenografts (PDXs) of prostate cancer for rapid and systematic evaluation of candidate therapies. The PDX collection comprises 59 tumors collected from 30 patients between 2012-2020, coinciding with availability of abiraterone and enzalutamide. The PDXs represent the clinico-pathological and genomic spectrum of prostate cancer, from treatment-naïve primary tumors to castration-resistant metastases. Inter- and intra-tumor heterogeneity in adenocarcinoma and neuroendocrine phenotypes is evident from bulk and single-cell RNA sequencing data. Organoids can be cultured from PDXs, providing further capabilities for preclinical studies. Using a 1 x 1 x 1 design, we rapidly identify tumors with exceptional responses to combination treatments. To govern the distribution of PDXs, we formed the Melbourne Urological Research Alliance (MURAL). This PDX collection is a substantial resource, expanding the capacity to test and prioritize effective treatments for prospective clinical trials in prostate cancer.

Inequalities in HIV testing uptake and needs among men who have sex with men living in Ireland: findings from an internet survey

OBJECTIVES

HIV disproportionately affects men who have sex with men (MSM) in Ireland. The aim of this study was to improve understanding of HIV testing among MSM living in Ireland to inform prevention and testing initiatives.

METHODS

We used data from the MSM Internet Survey Ireland 2015 (MISI 2015), a cross-sectional survey of MSM living in Ireland. We identified factors associated with never having tested for HIV using univariable and multivariable logistic regression. We identified preferred sites for future tests and examined the relationships between unmet HIV testing needs and socio-demographic groups.

RESULTS

More than one-third (n = 1006; 36%) of MSM had never tested for HIV. Multivariable logistic regression showed that untested men were more likely to be aged 18-24 years, live outside Dublin, have a lower level of education, be born in Ireland, identify as bisexual, be out to fewer people, and not have had sex with a man in the previous 12 months. The same groups of men also had the least knowledge about HIV and were least confident in accessing an HIV test. Men who had never tested for HIV were more likely to prefer testing by their general practitioner (GP) or using home sampling HIV kits and less likely to prefer testing in a sexual health clinic.

CONCLUSIONS

HIV prevention and testing programmes for MSM should be targeted towards younger men, those living outside Dublin and those with lower levels of education. We recommend increased promotion and availability of free HIV testing services in a range of clinical and nonclinical settings (including self-sampling and home testing).

Immunological efficacy of pneumococcal vaccine strategies in HIV-infected adults: a randomized clinical trial

The aim of this study was to compare the immunologic response to a prime-boost immunization strategy combining the 13-valent conjugate pneumococcal vaccine (PCV13) with the 23-valent polysaccharide pneumococcal vaccine (PPSV23) versus the PPSV23 alone in HIV-infected adults. HIV-infected adults were randomized to receive PCV13 at week 0 followed by PPSV23 at week 4 (n = 31, prime-boost group) or PPSV23 alone at week 4 (n = 33, PPSV23-alone group). Serotype specific IgG geometric mean concentration (GMC) and functional oposonophagocytic (OPA) geometric mean titer (GMT) were compared for 12 pneumococcal serotypes shared by both vaccines at week 8 and week 28. The prime-boost vaccine group were more likely to achieve a ≥2-fold increase in IgG GMC and a GMC >1 ug/ml at week 8 (odds ratio (OR) 2.00, 95% confidence interval (CI) 1.46–2.74, p < 0.01) and week 28 (OR 1.95, 95% CI 1.40–2.70, p < 0.01). Similarly, the prime-boost vaccine group were more likely to achieve a ≥4-fold increase in GMT at week 8 (OR 1.71, 95% CI 1.22–2.39, p < 0.01) and week 28 (OR 1.6, 95% CI 1.15–2.3, p < 0.01). This study adds to evidence supporting current pneumococcal vaccination recommendations combining the conjugate and polysaccharide pneumococcal vaccines in the United States and Europe for HIV-infected individuals.

HPV vaccine acceptability in HIV-infected and HIV negative men who have sex with men (MSM) in Ireland

Background Men who have sex with men (MSM), particularly HIV-infected MSM are disproportionately affected by HPV infection and associated disease. The HPV vaccine has potential to greatly reduce the burden of HPV-associated disease including anal cancer in MSM. The efficacy of the HPV vaccine is dependent on high levels of vaccine uptake. The aim of this study was to examine HPV vaccine acceptability and factors influencing vaccine acceptability in MSM in Ireland. Methods A self-administered survey was distributed to HIV-infected and HIV negative MSM examining HPV vaccine acceptability and factors associated with vaccine acceptability. Logistic regression was used to identify key variables and predictors of HPV vaccine acceptability. Results 302 MSM participated in the study. Acceptability of HPV vaccine was 31% (unconditional), 51% (conditional on stated efficacy and a cost of €300), 65% (conditional on stated efficacy and a cost of €100) and 78% (conditional on stated efficacy and no cost). Cost was negatively associated with HPV vaccine acceptability (p<0.01) while knowledge of HPV vaccine efficacy was significantly associated with vaccine acceptability, even in the context of associated cost (p<0.01). Conclusions Acceptability of HPV vaccine in MSM in Ireland is high based on no cost vaccine and on stated vaccine efficacy (78%). Cost is negatively associated with vaccine acceptability. Understanding levels of knowledge of HPV infection, HPV associated disease and attitudes toward HPV vaccination are important as they will contribute to HPV vaccine acceptability among MSM and will help guide effective preventive programs.

Smoking Behaviour Among People Living with HIV and AIDS: A Sub-Group Comparison

Recent advancements in the treatment of HIV have significantly improved long-term health outcomes and life expectancy among people living with HIV/AIDS. As such, healthcare professionals have begun to focus more seriously on health protective behaviour changes that could further reduce mortality including smoking and tobacco dependence. A cross-sectional survey was conducted with 438 people living with HIV/AIDS (PLWHA) attending a clinic in an urban area to measure current smoking behaviours. After removing missing data, the final sample was 402 service users. Among those surveyed 141 (35.0%) were current smokers with 35 (8.2%) ex-smokers. Rates among key sub-groups were higher. Comparatively, smoking prevalence was very low among African migrants (8, 7.2%), particularly African born women (1, 1.3%). In line with international studies, smoking prevalence among PLWHA was nearly double that of the general population. These findings come at a time when smoking in the general population in Ireland is at an all-time low, making the need to address tobacco dependence among PLWHA all the more vital.

Transmission of HIV Drug Resistance and the Predicted Effect on Current First-line Regimens in Europe

Transmitted human immunodeficiency virus drug resistance in Europe is stable at around 8%. The impact of baseline mutation patterns on susceptibility to antiretroviral drugs should be addressed using clinical guidelines. The impact on baseline susceptibility is largest for nonnucleoside reverse transcriptase inhibitors.

Background. Numerous studies have shown that baseline drug resistance patterns may influence the outcome of antiretroviral therapy. Therefore, guidelines recommend drug resistance testing to guide the choice of initial regimen. In addition to optimizing individual patient management, these baseline resistance data enable transmitted drug resistance (TDR) to be surveyed for public health purposes. The SPREAD program systematically collects data to gain insight into TDR occurring in Europe since 2001.

Methods. Demographic, clinical, and virological data from 4140 antiretroviral-naive human immunodeficiency virus (HIV)–infected individuals from 26 countries who were newly diagnosed between 2008 and 2010 were analyzed. Evidence of TDR was defined using the WHO list for surveillance of drug resistance mutations. Prevalence of TDR was assessed over time by comparing the results to SPREAD data from 2002 to 2007. Baseline susceptibility to antiretroviral drugs was predicted using the Stanford HIVdb program version 7.0.

Results. The overall prevalence of TDR did not change significantly over time and was 8.3% (95% confidence interval, 7.2%–9.5%) in 2008–2010. The most frequent indicators of TDR were nucleoside reverse transcriptase inhibitor (NRTI) mutations (4.5%), followed by nonnucleoside reverse transcriptase inhibitor (NNRTI) mutations (2.9%) and protease inhibitor mutations (2.0%). Baseline mutations were most predictive of reduced susceptibility to initial NNRTI-based regimens: 4.5% and 6.5% of patient isolates were predicted to have resistance to regimens containing efavirenz or rilpivirine, respectively, independent of current NRTI backbones.

Conclusions. Although TDR was highest for NRTIs, the impact of baseline drug resistance patterns on susceptibility was largest for NNRTIs. The prevalence of TDR assessed by epidemiological surveys does not clearly indicate to what degree susceptibility to different drug classes is affected.

Clinical and epidemiological characteristics of patients with early syphilis from three academic centres in Poland, Germany and Ireland: initial findings from the POETS study

OBJECTIVES

Syphilis recognition in HIV-positive patients has important implications. Initial data from this study, established in June 2012 to better understand the natural history of syphilis and treatment response, examine the characteristics of patients including sexual behaviour, rates of concurrent sexually transmitted infections (STI) and type of treatment given.

METHODS

Patients were recruited from Ireland, Poland and Germany. Data gathered included demographics, method of syphilis acquisition, stage of syphilis infection, HIV status, nadir and current CD4 counts and HIV viral suppression rates. Data were then subanalysed into HIV-positive and HIV-negative groups.

RESULTS

Of 175 patients recruited, 68% were HIV-positive and 86.3% were men who have sex with men. Most HIV-positive patients presented with secondary syphilis (55.7% vs 13.2%) (p=0.0001) while the majority of HIV-negative patients had primary syphilis noted at the time of recruitment (47.2% vs18.9%, p=0.0002). Approximately half of all patients had a HIV RNA viral load <40 copies/mL (55%). Previous syphilis infection occurred more frequently in HIV-positive than HIV-negative patients (p=0.0001). Concurrent STIs at the time of syphilis diagnosis were found in 26.8%, of whom 31 (25.4%) were HIV-positive (p=0.64). HIV-positive patients received doxycycline more frequently than their HIV-negative counterparts (33.6% vs 1.9%, p=0.0001) while HIV-negative patients were treated with long-acting penicillin in 88.7% of cases vs 58% of HIV-positive patients (p=0.0002).

CONCLUSIONS

A 40% rate of unsuppressed viraemia, high levels of STIs and varying treatment regimens represent a public health risk for Europe, suggesting the model of sexual healthcare delivery in HIV-positive patients requires further evaluation.

Circulating CD56dim natural killer cells and CD56+ T cells that produce interferon-γ or interleukin-10 are expanded in asymptomatic, E antigen-negative patients with persistent hepatitis B virus infection

Infection with hepatitis B virus (HBV) can result in spontaneous resolution or chronic infection, which can remain asymptomatic or can progress to cirrhosis and/or hepatocellular carcinoma. The host immune response is thought to be a major determinant of the outcome of HBV infection and virus-specific cytotoxic T lymphocytes (CTL) can mediate immunity against the virus and cause liver pathology. Antigen-nonspecific innate lymphocytes may also contribute to HBV infection and liver disease, therefore, we examined the frequencies, phenotypes, cytolytic activities and cytokine profiles of circulating natural killer (NK) cells, CD1d-restricted invariant natural killer T (iNKT) cells and CD56(+) T cells in 102 asymptomatic HBV-infected patients and compared them with those in 66 uninfected control subjects. NK cells expressing low levels of CD56 (CD56(dim)) and CD56(+) T cells were significantly expanded in the circulation of HBV-infected patients compared with control subjects. CD1d expression and iNKT cell frequencies were similar in both groups. Despite these expansions, we did not detect augmented natural or cytokine-induced cytotoxicity in the HBV-infected subjects. All lymphocyte populations studied produced interferon-γ (IFN-γ) significantly more frequently when taken from HBV-infected patients compared with when taken from healthy controls. Additionally, NK cells from the patients more frequently produced interleukin-10. As our HBV-infected cohort consisted of asymptomatic patients with low viral loads, we propose that CD56(dim) NK cells and CD56(+) T cells control HBV infection by noncytolytic mechanisms.

Clinically significant extra-cardiac findings in asymptomatic HIV-positive men undergoing cardiac magnetic resonance imaging

Increased research-based imaging has led to an increase in clinically significant extra-cardiac findings. HIV patients are at increased risk of having polypathology at a younger age; therefore, it may be hypothesised that they would have more incidental findings on imaging. We reviewed the magnetic resonance imaging results of 169 HIV-positive and 40 HIV-negative, clinically well volunteers undergoing cardiac magnetic resonance imaging scanning to assess the prevalence of subclinical cardiac pathology. This sub-study assessed the prevalence of clinically significant extra-cardiac findings. Associated risk factors were assessed and clinical follow-up and outcome were ascertained. Of the HIV-positive study group, 12/169 (7.1%) vs. 1/40 (2.5%) control patients had a clinically significant extra-cardiac finding which warranted further radiological or clinical intervention (p = 0.28). A total of three out of 169 (1.1%) were highly clinically significant findings. On logistic regression analysis, age was the only significant contributing factor (p = 0.049); no HIV-associated factors were found to be significant. The prevalence of clinically significant extra-cardiac findings of 7.1% in this HIV-positive cohort is comparable to the prevalence found in previous studies carried out on an older, sicker general population. This highlights the need for planning for unexpected outcomes and also the high rate of clinically significant findings in a seemingly well HIV-positive population.

Prevalence of human papillomavirus in men who have sex with men in the era of an effective vaccine; a call to act

OBJECTIVES

The incidence of human papillomavirus (HPV)-associated anal cancer is increasing. Men who have sex with men (MSM), particularly those coinfected with HIV, are disproportionately affected. Documenting the molecular epidemiology of HPV infection is important in guiding policy makers in formulating universal and/or targeted vaccine guidelines.

METHODS

A prospective cohort study was conducted. HIV-positive and HIV-negative MSM > 18 years old were invited to participate. Provider-performed anal swabs were collected and anal HPV infection was detected using consensus primer solution phase polymerase chain reaction (PCR) followed by type-specific PCR for high-risk (HR)-HPV types 16, 18 and 31. Between-group differences were analysed using χ(2) tests and Wilcoxon rank tests.

RESULTS

One hundred and ninety-four MSM [mean (standard deviation (SD)) age 36 (10) years; 51% HIV-positive) were recruited. The median number of sexual contacts in the preceding 12 months was 4 (interquartile range 2-10). HIV-positive subjects had a mean (SD) CD4 count of 557 (217) cells/μL, and 84% were on highly active antiretroviral therapy (HAART). Thirty-one samples were B-globin negative and thus excluded from further analysis. A total of 113 subjects (69%) had detectable HPV DNA. Sixty-eight subjects (42%) had an HR-HPV type detected. HR HPV type 16 was detected in 44 samples (27%), HR-HPV type 18 in 26 samples (16%) and HR-HPV type 31 in 14 samples (23%). Twenty-eight subjects (17%) had more than one type of HR-HPV type detected. When HPV and HR-HPV were stratified by age, those > 35 years had a higher prevalence (P = 0.001 and P = 0.028, respectively). HIV-positive subjects were more likely than HIV-negative subjects to have any detectable HPV (77% vs. 61%, respectively; P = 0.04), to have HR-HPV type 18 or 31 (P = 0.05 and P = 0.006, respectively) and to be infected with more than one HR-HPV type (31% vs. 3%, respectively; P < 0.001). Within the HIV-positive group, the prevalence of HPV was higher in those not on HAART (P = 0.041), although it did not differ when stratified by CD4 count.

CONCLUSIONS

The identified prevalence of anal HPV infection was high. Emerging patterns of HPV-related disease strengthen the call for universal vaccination of boys and girls with consideration of catch-up and targeted vaccination of high-risk groups such as MSM and those with HIV infection.

Use of the Alcohol Use Disorders Identification Test (AUDIT) to determine the prevalence of alcohol misuse among HIV-infected individuals

The aim of the paper is to evaluate alcohol misuse among an inner city adult HIV clinic population with AUDIT (Alcohol Use Disorders Identification Test). A cross-sectional HIV outpatient clinic analysis between 28 February 2011 and 11 March 2011 was carried out. AUDIT, demographic and clinical data were collected. Univariate analysis was performed to look for the associations between variables. Backward stepwise multivariate analyses were performed on significant variables from the univariate analysis to assess for predictors of alcohol dependence. In total, 111 patients were included (60% uptake of clinic attendees); 66% were men and 26% were hepatitis C virus (HCV) co-infected. The median AUDIT score was 5 (within normal range). Thirty-four 'AUDIT positive' cases were identified: five (4.5%) indicated consumption of hazardous levels of alcohol; 21 (19%) indicated harmful levels of alcohol; and eight (7%) were likely alcohol dependent. Younger age (<40 years old) was significantly associated with AUDIT positivity (P = 0.006). On multivariate analysis younger age (P = 0.045, odds ratio 13.8) and lower level of education (P = 0.006, odds ratio 6.7) were predictive of scores indicative of alcohol dependence (AUDIT ≥20). In conclusion, younger age and lower educational levels were associated with scores consistent with alcohol dependence. AUDIT was well tolerated and easy to administer in this outpatient HIV clinic population.

Long-term neurological follow-up of HIV-positive patients diagnosed with syphilis

No cerebrospinal fluid (CSF) abnormalities are found in HIV-positive patients in long-term follow-up after standard syphilis treatment. Syphilis has been reported to have immunological effects on HIV infection and HIV is known to modulate both the manifestations of syphilis and the serological response to therapy. HIV-positive patients who had been diagnosed with and treated for syphilis prior to 2007 were identified. Patients were consented for lumbar puncture. Serum HIV viral load, CD4 count and CSF were recorded. Thirty-five patients with previously diagnosed and treated syphilis underwent lumbar puncture. Thirty-four patients had a normal neurological exam. Only one patient had an abnormal mean white cell count (10.7 cells per high-power field). The finding that those with previously diagnosed syphilis had normal CSF and clinical findings is reassuring and supports the practice of using standard syphilis therapy in HIV-positive patients.

Soluble signals from mechanically disrupted lung tissue induce lung-related gene expression in bone marrow-derived cells in vitro

Differentiation of bone marrow (BM)-derived cells into lung epithelial cells has been reported in vivo in animal models of lung injury. Most studies have used cytokeratin or surfactant protein expression as markers of BM-to-lung cell differentiation. However, concerns as to whether fusion rather than differentiation is the mechanism involved, verification of BM-derived lung cells, and inconsistent findings with different injury models mean that the differentiation potential of BM-derived cells remains unclear. We used a co-culture system, in which BM cell-lung cell fusion is prevented, to examine the ability of 'damage' signals released from mechanically disrupted lung tissue to induce expression of lung-related genes in BM-derived cells in vitro. BM-derived hematopoietic progenitor cells (BM-HPCs) were co-cultured with mechanically disrupted lung tissue. Liver tissue and medium-only co-cultures were also studied as controls. BM-HPCs differentiated into myeloid cells in culture. BM-HPCs proliferated in response to soluble lung damage signals and differentiated into suspension and adherent populations with dendritic cell and Langerhans cell-like characteristics, respectively. Cytokeratins 7 and 18 and surfactant protein B mRNA expression was either induced or upregulated in the dendritic cell (DC)-like population in lung co-cultures. In contrast, these genes were not induced or up-regulated in medium only or liver co-cultures. Up-regulation of E-cadherin mRNA and protein expression also occurred in response to lung damage signals. These results confirm that signals released from damaged lung tissue can induce lung-related gene expression in BM-derived DC-like cells in the absence of cell fusion.

CFTR gene transfer to lung epithelium--on the trail of a target cell

Cystic fibrosis (CF) is a lethal inherited disease that afflicts up to 1 in 2,500 people in the western world. Since 1989, when mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene were identified as responsible for the disease, intense effort has been applied to the development of replacement gene therapy strategies to cure CF. Problems with basic gene delivery techniques along with limited knowledge of the pathogenesis of CF have hindered progress so far. However, recent insights into the expression patterns and functions of CFTR in developing and adult lungs are now advancing our understanding of this disease. It is becoming apparent that progress in gene delivery to cure CF may be best served by identification of a target cell(s) around which gene transfer strategies can be specifically tailored to most closely reproduce the effects of normal CFTR expression. In fact, accurate restoration of endogenous expression patterns may be crucial, not only for disease reversal, but also to avoid potentially deleterious effects of inappropriate expression. This approach is in turn confounded however, by ill-defined stem and progenitor cell pathways within the lung epithelium. Nonetheless, studies to date suggest that these pathways are relatively plastic and may respond differently during homeostasis compared with repair following injury. It may therefore be feasible to target the lung epithelium in a non-cell specific manner and allow endogenous differentiation pathways to subsequently establish correct CFTR distribution patterns. In this review, emerging information on CFTR expression and function in developing and adult lungs is discussed in the context of putative stem cell populations and their potential for current gene delivery approaches.

Immunologic assessment of a cluster of asymptomatic HTLV-I-infected individuals in New Orleans

PURPOSE

Although clusters of individuals infected with the human T-cell lymphotrophic virus type I (HTLV-I) have been identified in the United States, no systematic evaluation of the immunologic status of these persons has been reported. We therefore studied a group of 11 HTLV-I-infected former intravenous drug abusers who were long-term participants in a methadone maintenance program in New Orleans, Louisiana, to determine the effects of HTLV-I and chronic opiate use on immunity.

PATIENTS AND METHODS

Mitogenic responses and results of serologic studies, cell phenotype analysis, and cytotoxicity assays were compared to those in two other HTLV-I seronegative groups: a similar group of 17 methadone users and 15 healthy age-, sex-, and race-matched control subjects. All study participants were seronegative for human immunodeficiency virus type 1.

RESULTS

Percentages and numbers of total T lymphocytes (CD2+,CD3+), T-suppressor/cytotoxic lymphocytes (CD8+), cytotoxic lymphocytes (Leu7+, Leu11+, NKH-1+) and B lymphocytes (B4+) were similar among the study groups. Although percentages and numbers of total T-helper lymphocytes (CD4+) were also similar among the groups, HTLV-I-infected subjects had higher percentages and proportions of helper/inducer cells (CD4:4B4+) than did HTLV-I seronegative methadone users. Both methadone using groups had decreased percentages and numbers of suppressor/inducer T lymphocytes (CD4:2H4+). Major histocompatibility complex unrestricted T-cell cytotoxicity (lectin-dependent cellular cytotoxicity), natural killer cell function, and mitogenic responses to the T-cell mitogen phytohemagglutin were similar among the three study groups. Pokeweed mitogen responses were severely depressed in the HTLV-I-infected population.

CONCLUSIONS

We conclude that HTLV-I infection is associated with abnormalities in T-cell-dependent B-cell proliferative responses. Furthermore, both long-term methadone use and HTLV-I infection are associated with abnormalities in the distribution of CD4+ cell subpopulations. The increase in the helper/inducer and T-cell cell populations and decrease in the pokeweed mitogenic response noted in HTLV-I-infected subjects appear to be markers for infection with this retrovirus.