Epithelial and Stromal Characteristics of Primary Tumors Predict the Bone Metastatic Subtype of Prostate Cancer and Patient Survival after Androgen-Deprivation Therapy.

Prostate cancer (PC) bone metastases can be divided into transcriptomic subtypes, by us termed MetA-C. The MetB subtype, constituting about 20% of the cases, is characterized by high cell cycle activity, low androgen receptor (AR) activity, and a limited response to standard androgen deprivation therapy (ADT). Complementary treatments should preferably be introduced early on if the risk of developing metastases of the MetB subtype is predicted to behigh. In this study, we therefore examined if the bone metastatic subtype and patient outcome after ADT could be predicted by immunohistochemical analysis of epithelial and stromal cell markers in primary tumor biopsies obtained at diagnosis (n = 98). In this advanced patient group, primary tumor International Society of Urological Pathology (ISUP) grade was not associated with outcome or metastasis subtype. In contrast, high tumor cell Ki67 labeling (proliferation) in combination with low tumor cell immunoreactivity for PSA, and a low fraction of AR positive stroma cells in the primary tumors were prognostic for poor survival after ADT. Accordingly, the same tissue markers were associated with developing metastases enriched for the aggressive MetB subtype. The development of the contrasting MetA subtype, showing the best response to ADT, could be predicted by the opposite staining pattern. We conclude that outcome after ADT and metastasis subtype can, at least to some extent, be predicted by analysis of primary tumor characteristics, such as tumor cell proliferation and PSA expression, and AR expression in stromal cells.

Rat prostate tumors induce DNA synthesis in remote organs.

Advanced cancers induce systemic responses. However, if such systemic changes occur already when aggressive tumors are small, have not been thoroughly characterized. Here, we examined how localized prostate cancers of different sizes and metastatic potential affected DNA synthesis in the rest of the prostate and in various remote organs. Non-metastatic Dunning R-3327 G (G) tumor cells, metastatic MatLyLu (MLL) tumor cells, or vehicle were injected into the prostate of immunocompetent rats. All animals received daily injections of Bromodeoxyuridine (BrdU), to label cells/daughter cells with active DNA synthesis. Equal sized G- and MLL-tumors, similarly increased BrdU-labeling in the prostate, lymph nodes and liver compared to tumor-free controls. Prior to metastasis, MLL-tumors also increased BrdU-labeling in bone marrow and lungs compared to animals with G-tumors or controls. In animals with MLL-tumors, BrdU-labeling in prostate, lungs, brown adipose tissue and skeletal muscles increased in a tumor-size-dependent way. Furthermore, MLL-tumors induced increased signs of DNA damage (γH2AX staining) and accumulation of CD68 + macrophages in the lungs. In conclusion, small localized prostate cancers increased DNA synthesis in several remote tissues in a tumor type- and size-dependent way. This may suggest the possibility for early diagnosis of aggressive prostate cancer by examining tumor-induced effects in other tissues.

Bone Cell Activity in Clinical Prostate Cancer Bone Metastasis and Its Inverse Relation to Tumor Cell Androgen Receptor Activity.

Advanced prostate cancer frequently metastasizes to bone and induces a mixed osteoblastic/osteolytic bone response. Standard treatment for metastatic prostate cancer is androgen-deprivation therapy (ADT) that also affects bone biology. Treatment options for patients relapsing after ADT are limited, particularly in cases where castration-resistance does not depend on androgen receptor (AR) activity. Patients with non-AR driven metastases may, however, benefit from therapies targeting the tumor microenvironment. Therefore, the current study specifically investigated bone cell activity in clinical bone metastases in relation to tumor cell AR activity, in order to gain novel insight into biological heterogeneities of possible importance for patient stratification into bone-targeting therapies. Metastasis tissue obtained from treatment-naïve (n = 11) and castration-resistant (n = 28) patients was characterized using whole-genome expression analysis followed by multivariate modeling, functional enrichment analysis, and histological evaluation. Bone cell activity was analyzed by measuring expression levels of predefined marker genes representing osteoclasts (ACP5, CTSK, MMP9), osteoblasts (ALPL, BGLAP, RUNX2) and osteocytes (SOST). Principal component analysis indicated a positive correlation between osteoblast and osteoclast activity and a high variability in bone cell activity between different metastases. Immunohistochemistry verified a positive correlation between runt-related transcription factor 2 (RUNX2) positive osteoblasts and tartrate-resistant acid phosphatase (TRAP, encoded by ACP5) positive osteoclasts lining the metastatic bone surface. No difference in bone cell activity was seen between treatment-naïve and castration-resistant patients. Importantly, bone cell activity was inversely correlated to tumor cell AR activity (measured as AR, FOXA1, HOXB13, KLK2, KLK3, NKX3-1, STEAP2, and TMPRSS2 expression) and to patient serum prostate-specific antigen (PSA) levels. Functional enrichment analysis indicated high bone morphogenetic protein (BMP) signaling in metastases with high bone cell activity and low tumor cell AR activity. This was confirmed by BMP4 immunoreactivity in tumor cells of metastases with ongoing bone formation, as determined by histological evaluation of van Gieson-stained sections. In conclusion, the inverse relation observed between bone cell activity and tumor cell AR activity in prostate cancer bone metastasis may be of importance for patient response to AR and/or bone targeting therapies, but needs to be evaluated in clinical settings in relation to serum markers for bone remodeling, radiography and patient response to therapy. The importance of BMP signaling in the development of sclerotic metastasis lesions deserves further exploration.

Inhibition of the insulin-like growth factor-1 receptor potentiates acute effects of castration in a rat model for prostate cancer growth in bone.

Prostate cancer (PCa) patients with bone metastases are primarily treated with androgen deprivation therapy (ADT). Less pronounced ADT effects are seen in metastases than in primary tumors. To test if acute effects of ADT was enhanced by concurrent inhibition of pro-survival insulin-like growth factor 1 (IGF-1), rats were inoculated with Dunning R3327-G tumor cells into the tibial bone marrow cavity and established tumors were treated with castration in combination with IGF-1 receptor (IGF-1R) inhibitor NVP-AEW541, or by each treatment alone. Dunning R3327-G cells were stimulated by androgens and IGF-1 in vitro. In rat tibia, Dunning R3327-G cells induced bone remodeling, identified through increased immunoreactivity of osteoblast and osteoclast markers. Tumor cells occasionally grew outside the tibia, and proliferation and apoptotic rates a few days after treatment were evaluated by scoring BrdU- and caspase-3-positive tumor cells inside and outside the bone marrow cavity, separately. Apoptosis was significantly induced outside, but unaffected inside, the tibial bone by either castration or NVP-AEW541, and the maximum increase (2.7-fold) was obtained by the combined treatment. Proliferation was significantly reduced by NVP-AEW541, independently of growth site, although the maximum decrease (24%) was observed when NVP-AEW541 was combined with castration. Tumor cell IGF-1R immunoreactivity was evaluated in clinical PCa bone metastases (n = 61), and positive staining was observed in most cases (74%). In conclusion, IGF-1R inhibition may be evaluated in combination with ADT in patients with metastatic PCa, or in combination with therapies for the subsequent development of castration-resistant disease, although diverse responses could be anticipated depending on metastasis site.

Perspectives and experiences of new migrants on health screening in Sweden.

BACKGROUND: In Sweden, migrants from countries considered to have a high burden of certain infectious diseases are offered health screening to prevent the spread of these diseases, but also identify their health needs. However, very little is known about their experiences and perceptions about the screening process. This study aimed at exploring these perceptions and experiences in order to inform policy and clinical practice. METHOD: Using an interpretive description framework, 26 new migrants were interviewed between April and June 2013 in four Swedish counties. Thematic analysis was used to analyze data. RESULTS: The three themes developed include: new country, new practices; new requirements in the new country; and unmet needs and expectations. Participants described what it meant for them to come to a new country with a foreign language, new ways of communicating with caregivers/authorities and being offered health screening without clarification. Participants perceived health screening as a requirement from the authorities to be fulfilled by all newcomers but conceded that it benefits equally the host society and themselves. However, they also expressed concern over the involvement of the Migration Board staff and feared possible collaboration with health service to their detriment. They further stated that the screening program fell short of their expectations as it mainly focused on identifying infectious diseases and overlooked their actual health needs. Finally, they expressed frustration over delay in screening, poor living conditions in reception centers and the restrictive entitlement to care. CONCLUSIONS: Migrants are aware of their vulnerability and the need to undergo health screening though they view it as an official requirement. Thus, those who underwent the screening were more concerned about residency rather than the actual benefits of screening. The issues highlighted in this study may limit access to and uptake of the screening service, and compromise its effectiveness. To maximize the uptake: (1) linguistically and culturally adapted information is needed, (2) other screening approaches should be tried, (3) trained medical interpreters should be used, (4) a holistic and human right approach should be applied, (5) the involvement of migration staff should be reconsidered to avoid confusion and worries. Finally, to improve the effectiveness, (6) all migrants from targeted countries should be offered screening and efforts should be taken to improve the health literacy of migrants and the living conditions in reception centers.

'It is a dilemma': perspectives of nurse practitioners on health screening of newly arrived migrants.

BACKGROUND: Screening newly arrived migrants from countries with high burden of communicable diseases of public health significance is part of the Swedish national strategy against the spread of these diseases. However, little is known about its implementation. OBJECTIVE: This study aimed at exploring caregivers' experiences in screening newly arrived migrants to generate knowledge that could inform policy and clinical practice. DESIGN: Using an interpretive description framework, we conducted semistructured interviews between November and December 2011 in four Swedish counties, with 15 purposively selected nurses with experience in screening migrants. Data were analyzed using thematic analysis. RESULTS: Participants described a range of challenges including discordant views between migrants and the nurses about medical screening, inconsistencies in rules and practices, and conflicting policies. Participants indicated that sociocultural differences resulted in divergent expectations with migrants viewing the participants as agents of migration authorities. They also expressed concern over being given a new assignment without training and being expected to share responsibilities with staff from other agencies without adequate coordination. Finally, they indicated that existing policies can be confusing and raise ethical issues. All these were compounded by language barriers, making their work environment extremely complex and stressful. CONCLUSIONS: These findings illuminate complex challenges that could limit access to, uptake, and delivery of health screening and undermine public health goals, and highlight the need for a multilevel approach. This entails avoiding the conflation of migration with health issues, harmonizing existing policies to make health care services more accessible and acceptable to migrants, and facilitating health professionals' work in promoting public health, improving interagency collaboration and the skills of all staff involved in understanding and effectively responding to migrants' needs, and improving migrants' health literacy through community outreach interventions.

Inhibition of the insulin-like growth factor-1 receptor enhances effects of simvastatin on prostate cancer cells in co-culture with bone.

Prostate cancer (PC) bone metastases show weak responses to conventional therapies. Bone matrix is rich in growth factors, with insulin-like growth factor-1 (IGF-1) being one of the most abundant. IGF-1 acts as a survival factor for tumor cells and we speculate that bone-derived IGF-1 counteracts effects of therapies aimed to target bone metastases and, consequently, that therapeutic effects could be enhanced if given in combination with IGF-1 receptor (IGF-1R) inhibitors. Simvastatin inhibits the mevalonate pathway and has been found to induce apoptosis of PC cells. The aims of this study were to confirm stimulating effects of bone-derived IGF-1 on PC cells and to test if IGF-1R inhibition enhances growth inhibitory effects of simvastatin on PC cells in a bone microenvironment. The PC-3 and 22Rv1 tumor cell lines showed significantly induced cell growth when co-cultured with neonatal mouse calvarial bones. The tumor cell IGF-1R was activated by calvariae-conditioned media and neutralization of bone-derived IGF-1 abolished the calvarium-induced PC-3 cell growth. Treatment of PC-3 and 22Rv1 cells with simvastatin, or the IGF-1R inhibitor NVP-AEW541, reduced tumor cell numbers and viability, and induced apoptosis. Combined simvastatin and NVP-AEW541 treatment resulted in enhanced growth inhibitory effects compared to either drug given alone. Effects of simvastatin involved down-regulation of IGF-1R in PC-3 and of constitutively active androgen receptor variants in 22Rv1 cells. In conclusion, we suggest that IGF-1 inhibition may be a way to strengthen effects of apoptosis-inducing therapies on PC bone metastases; a possibility that needs to be further tested in pre-clinical models.

Establishment and validation of an in vitro co-culture model to study the interactions between bone and prostate cancer cells.

Bone is the preferred site for prostate cancer (PCa) metastases. Once the tumor has established itself within the bone there is virtually no cure. To better understand the interactions between the PCa cells and bone environment in the metastatic process new model systems are needed. We have established a two-compartment in vitro co-culturing model that can be used to follow the trans-activation of bone and/or tumor cells. The model was validated using two PCa tumor cell lines (PC-3; lytic and LNCaP; mixed/osteoblastic) and one osteolytic inducing factor, 1,25-dihydroxyvitamin D(3) (D3). Results were in accordance with the expected bone phenotypes; PC-3 cells and D3 gave osteolytic gene expression profiles in calvariae, with up-regulation of genes needed for osteoclast differentiation, activation and function; Rankl, CathK, Trap and MMP-9, and down-regulation of genes associated with osteoblast differentiation and bone mineralization; Alp, Ocl and Dkk-1. LNCaP cells activated genes in the calvarial bones associated with osteoblast differentiation and mineralization, with marginal effects on osteolytic genes. The results were strengthened by similar changes in protein expression for a selection of the analyzed genes. Furthermore, the osteolytic gene expression profiles in calvarial bones co-cultured with PC-3 cells or with D3 were correlated with the actual ongoing resorptive process, as assessed by the release of collagen fragments from the calvariae. Our results show that the model can be used to follow tumor-induced bone remodeling, and by measuring changes in gene expression in the tumor cells we can also study how they respond to the bone microenvironment.

Tickborne relapsing fever diagnosis obscured by malaria, Togo.

Given the prevalence of relapsing fever (RF) in Senegal, this disease may cause illness and death in other areas of West Africa. We performed a cross-sectional, clinic-based study to investigate the presence of RF in Togo during 2002-2004. Blood samples from patients with fever were examined for RF spirochetes by microscopy, PCR, and DNA sequencing of amplicons and for antibodies to the glycerophosphodiester phosphodiesterase antigen. Although no spirochetes were seen in blood smears, approximately 10% of the patients were positive by PCR and approximately 13% were seropositive for spirochetes. DNA sequencing demonstrated that Borrelia crocidurae and B. duttonii were present. Most patients were treated for malaria whether or not plasmodia were observed. Thus, many RF patients originally had a misdiagnosis of malaria, which resulted in ineffective treatment. The inability of microscopic analysis to detect spirochetes compared with PCR demonstrates the need for tests with greater sensitivity.

In situ immune response in brain and kidney during early relapsing fever borreliosis.

Characterization of the host immune response during initial pathogenesis of relapsing fever neuroborreliosis would be a key to understanding Borrelia persistence and factors driving the inflammatory process. We analyzed immune cells in brain and kidney with the highly invasive B. crocidurae during the first two weeks of murine infection. In both organs, microglia and/or macrophages predominated while T-cell changes were minimal. Compared to kidney, brain neutrophils infiltrated more rapidly and B-cells were essentially absent. Our results indicate that during early neuroborreliosis, brain defense is comprised primarily of innate immune cells while adaptive immunity plays a minor role.

Complications of pregnancy and transplacental transmission of relapsing-fever borreliosis.

Relapsing-fever borreliosis caused by Borrelia duttonii is a common cause of complications of pregnancy, miscarriage, and neonatal death in sub-Saharan Africa. We established a murine model of gestational relapsing fever infection for the study of the pathological development of these complications. We demonstrate that B. duttonii infection during pregnancy results in intrauterine growth retardation, as well as placental damage and inflammation, impaired fetal circulation, and decreased maternal hemoglobin levels. We show that spirochetes frequently cross the maternal-fetal barrier, resulting in congenital infection. Furthermore, we compared the severity of infection in pregnant and nonpregnant mice and show that pregnancy has a protective effect. This model closely parallels the consequences of human gestational infection, and our results provide insight into the mechanisms behind the complications of pregnancy that have been reported in human relapsing-fever infection.

Persistent brain infection and disease reactivation in relapsing fever borreliosis.

Relapsing fever, an infection caused by Borrelia spirochetes, is generally considered a transient, self-limiting disease in humans. The present study reveals that murine infection by Borrelia duttonii can be reactivated after an extended time as a silent infection in the brain, with no bacteria appearing in the blood and spirochete load comparable to the numbers in an infected tick. The host cerebral gene expression pattern is indistinguishable from that of uninfected animals, indicating that persistent bacteria are not recognized by the immune system nor cause noticeable tissue damage. Silent infection can be reactivated by immunosuppression, inducing spirochetemia comparable to that of initial densities. B. duttonii has never been found in any host except man and the tick vector. We therefore propose the brain to be a possible natural reservoir of the spirochete. The view of relapsing fever as an acute disease should be extended to include in some cases prolonged persistence, a feature characteristic of the related spirochetal infections Lyme disease and syphilis.