Generation of 3D ex vivo mouse- and patient-derived glioma explant slice model for integration of confocal time-lapse imaging and spatial analysis.

Development of spatial-integrative pre-clinical models is needed for glioblastoma, which are heterogenous tumors with poor prognosis. Here, we present an optimized protocol to generate three-dimensional ex vivo explant slice glioma model from orthotopic tumors, genetically engineered mouse models, and fresh patient-derived specimens. We describe a step-by-step workflow for tissue acquisition, dissection, and sectioning of 300-µm tumor slices maintaining cell viability. The explant slice model allows the integration of confocal time-lapse imaging with spatial analysis for studying migration, invasion, and tumor microenvironment, making it a valuable platform for testing effective treatment modalities. For complete details on the use and execution of this protocol, please refer to Comba et al. (2022).1.

Gene Therapy for High Grade Glioma: The Clinical Experience.

INTRODUCTION: High-grade gliomas (HGG) are the most common malignant primary brain tumors in adults, with a median survival of ~18 months. The standard of care (SOC) is maximal safe surgical resection, and radiation therapy with concurrent and adjuvant temozolomide. This protocol remains unchanged since 2005, even though HGG median survival has marginally improved. AREAS COVERED: Gene therapy was developed as a promising approach to treat HGG. Here, we review completed and ongoing clinical trials employing viral and non-viral vectors for adult and pediatric HGG, as well as the key supporting preclinical data. EXPERT OPINION: These therapies have proven safe, and pre- and post-treatment tissue analyses demonstrated tumor cell lysis, increased immune cell infiltration, and increased systemic immune function. Although viral therapy in clinical trials has not yet significantly extended the survival of HGG, promising strategies are being tested. Oncolytic HSV vectors have shown promising results for both adult and pediatric HGG. A recently published study demonstrated that HG47Δ improved survival in recurrent HGG. Likewise, PVSRIPO has shown survival improvement compared to historical controls. It is likely that further analysis of these trials will stimulate the development of new administration protocols, and new therapeutic combinations that will improve HGG prognosis.

Development of immunotherapy for high-grade gliomas: Overcoming the immunosuppressive tumor microenvironment.

The preclinical and clinical development of novel immunotherapies for the treatment of central nervous system (CNS) tumors is advancing at a rapid pace. High-grade gliomas (HGG) are aggressive tumors with poor prognoses in both adult and pediatric patients, and innovative and effective therapies are greatly needed. The use of cytotoxic chemotherapies has marginally improved survival in some HGG patient populations. Although several challenges exist for the successful development of immunotherapies for CNS tumors, recent insights into the genetic alterations that define the pathogenesis of HGG and their direct effects on the tumor microenvironment (TME) may allow for a more refined and targeted therapeutic approach. This review will focus on the TME in HGG, the genetic drivers frequently found in these tumors and their effect on the TME, the development of immunotherapy for HGG, and the practical challenges in clinical trials employing immunotherapy for HGG. Herein, we will discuss broadly the TME and immunotherapy development in HGG, with a specific focus on glioblastoma multiforme (GBM) as well as additional discussion in the context of the pediatric HGG diagnoses of diffuse midline glioma (DMG) and diffuse hemispheric glioma (DHG).

Histidine decarboxylase inhibitors: a novel therapeutic option for the treatment of leydigioma.

Recent reports indicate an increase in Leydig cell tumor (LCT) incidence. Radical orchiectomy is the standard therapy in children and adults, although it entails physical and psychosocial side effects. Testis-sparing surgery can be a consideration for benign LCT of 2.5 cm or less in size. Malignant LCTs respond poorly to conventional chemotherapy, so new treatment modalities are needed. In this study, we observed increased histidine decarboxylase expression and pro-angiogenic potential in LCT surgically resected from pediatric patients (fetal to pubertal) vs control samples from patients without endocrine or metabolic disorders which were collected at necropsy. We, therefore, evaluated for the first time the antitumor efficacy of two histidine decarboxylase inhibitors (α-methyl-dl-histidine dihydrochloride (α-MHD) and epigallocatechin gallate (EGCG)), alone and combined with carboplatin, in two preclinical models of LCT. MA-10 and R2C Leydig tumor cells, representing two different LCT subtypes, were used to generate syngeneic and xenograft mouse LCT models, respectively. In the syngeneic model, monotherapy with α-MHD effectively reduced tumor growth and angiogenesis. In the xenografts, which showed co-expression of histidine decarboxylase and CYP19, the combination of EGCG plus carboplatin was the most effective therapy, leading to LCT growth arrest and undetectable levels of plasmatic estradiol. Testicular and body weights remained unaltered. On the basis of this study, histidine decarboxylase may emerge as a novel pharmacological target for LCT treatment.

Spatiotemporal analysis of glioma heterogeneity reveals COL1A1 as an actionable target to disrupt tumor progression.

Intra-tumoral heterogeneity is a hallmark of glioblastoma that challenges treatment efficacy. However, the mechanisms that set up tumor heterogeneity and tumor cell migration remain poorly understood. Herein, we present a comprehensive spatiotemporal study that aligns distinctive intra-tumoral histopathological structures, oncostreams, with dynamic properties and a specific, actionable, spatial transcriptomic signature. Oncostreams are dynamic multicellular fascicles of spindle-like and aligned cells with mesenchymal properties, detected using ex vivo explants and in vivo intravital imaging. Their density correlates with tumor aggressiveness in genetically engineered mouse glioma models, and high grade human gliomas. Oncostreams facilitate the intra-tumoral distribution of tumoral and non-tumoral cells, and potentially the collective invasion of the normal brain. These fascicles are defined by a specific molecular signature that regulates their organization and function. Oncostreams structure and function depend on overexpression of COL1A1. Col1a1 is a central gene in the dynamic organization of glioma mesenchymal transformation, and a powerful regulator of glioma malignant behavior. Inhibition of Col1a1 eliminates oncostreams, reprograms the malignant histopathological phenotype, reduces expression of the mesenchymal associated genes, induces changes in the tumor microenvironment and prolongs animal survival. Oncostreams represent a pathological marker of potential value for diagnosis, prognosis, and treatment.

Uncovering Spatiotemporal Heterogeneity of High-Grade Gliomas: From Disease Biology to Therapeutic Implications.

Glioblastomas (GBM) are the most common and aggressive tumors of the central nervous system. Rapid tumor growth and diffuse infiltration into healthy brain tissue, along with high intratumoral heterogeneity, challenge therapeutic efficacy and prognosis. A better understanding of spatiotemporal tumor heterogeneity at the histological, cellular, molecular, and dynamic levels would accelerate the development of novel treatments for this devastating brain cancer. Histologically, GBM is characterized by nuclear atypia, cellular pleomorphism, necrosis, microvascular proliferation, and pseudopalisades. At the cellular level, the glioma microenvironment comprises a heterogeneous landscape of cell populations, including tumor cells, non-transformed/reactive glial and neural cells, immune cells, mesenchymal cells, and stem cells, which support tumor growth and invasion through complex network crosstalk. Genomic and transcriptomic analyses of gliomas have revealed significant inter and intratumoral heterogeneity and insights into their molecular pathogenesis. Moreover, recent evidence suggests that diverse dynamics of collective motion patterns exist in glioma tumors, which correlate with histological features. We hypothesize that glioma heterogeneity is not stochastic, but rather arises from organized and dynamic attributes, which favor glioma malignancy and influences treatment regimens. This review highlights the importance of an integrative approach of glioma histopathological features, single-cell and spatially resolved transcriptomic and cellular dynamics to understand tumor heterogeneity and maximize therapeutic effects.

Current Approaches for Glioma Gene Therapy and Virotherapy.

Glioblastoma (GBM) is the most common and aggressive primary brain tumor in the adult population and it carries a dismal prognosis. Inefficient drug delivery across the blood brain barrier (BBB), an immunosuppressive tumor microenvironment (TME) and development of drug resistance are key barriers to successful glioma treatment. Since gliomas occur through sequential acquisition of genetic alterations, gene therapy, which enables to modification of the genetic make-up of target cells, appears to be a promising approach to overcome the obstacles encountered by current therapeutic strategies. Gene therapy is a rapidly evolving field with the ultimate goal of achieving specific delivery of therapeutic molecules using either viral or non-viral delivery vehicles. Gene therapy can also be used to enhance immune responses to tumor antigens, reprogram the TME aiming at blocking glioma-mediated immunosuppression and normalize angiogenesis. Nano-particles-mediated gene therapy is currently being developed to overcome the BBB for glioma treatment. Another approach to enhance the anti-glioma efficacy is the implementation of viro-immunotherapy using oncolytic viruses, which are immunogenic. Oncolytic viruses kill tumor cells due to cancer cell-specific viral replication, and can also initiate an anti-tumor immunity. However, concerns still remain related to off target effects, and therapeutic and transduction efficiency. In this review, we describe the rationale and strategies as well as advantages and disadvantages of current gene therapy approaches against gliomas in clinical and preclinical studies. This includes different delivery systems comprising of viral, and non-viral delivery platforms along with suicide/prodrug, oncolytic, cytokine, and tumor suppressor-mediated gene therapy approaches. In addition, advances in glioma treatment through BBB-disruptive gene therapy and anti-EGFRvIII/VEGFR gene therapy are also discussed. Finally, we discuss the results of gene therapy-mediated human clinical trials for gliomas. In summary, we highlight the progress, prospects and remaining challenges of gene therapies aiming at broadening our understanding and highlighting the therapeutic arsenal for GBM.

Heme oxygenase-1 arrests Leydig cells functions and impairs their regulation by histamine.

Testicular Leydig cells (LC) are modulated by several pathways, one of them being the histaminergic system. Heme oxygenase-1 (HO-1), whose upregulation comprises the primary response to oxidative noxae, has a central homeostatic role and might dysregulate LC functions when induced. In this report, we aimed to determine how hemin, an HO-1 inducer, affects LC proliferative capacity and whether HO-1 effects on LC functions are reversible. It was also evaluated if HO-1 interacts in any way with histamine, affecting its regulatory action over LC. MA-10 and R2C cell lines and immature rat LC were used as models. Firstly, we show that after a 24-h incubation with 25 µmol/L hemin, LC proliferation is reversibly impaired by cell cycle arrest in G2/M phase, with no evidence of apoptosis induction. Even though steroid production is abrogated after a 48-h exposure to 25 µmol/L hemin, steroidogenesis can be restored to control levels in a time-dependent manner if the inducer is removed from the medium. Regarding HO-1 and histamine interaction, it is shown that hemin abrogates histamine biphasic effect on steroidogenesis and proliferation. Working with histamine receptors agonists, we elucidated that HO-1 induction affects the regulation mediated by receptor types 1, 2 and 4. In summary, HO-1 induction arrests LC functions, inhibiting steroid production and cell cycle progression. Despite their reversibility, HO-1 actions might negatively influence critical phases of LC development and differentiation affecting their function as well as other androgen-dependent organs. What's more, we have described a hitherto unknown interaction between HO-1 induction and histamine effects.

Enhanced recovery after surgery protocol versus conventional perioperative care in colorectal surgery: a single center cohort study / Aceleração da recuperação após protocolo cirúrgico versus cuidados perioperatórios convencionais em cirurgia colorretal: um estudo de coorte em centro único

Abstract Background Enhanced recovery after surgery (ERAS) protocols consist of a set of perioperative measures aimed at improving patient recovery and decreasing length of stay and postoperative complications. We assess the implementation and outcomes of an ERAS program for colorectal surgery. Methods Single center observational study. Data were collected from consecutive patients undergoing open or laparoscopic colorectal surgery during 2 time periods, 3 years before (Pre-ERAS) and 2 years after (Post-ERAS) the implementation of an ERAS protocol. Baseline characteristics of both groups were compared. The primary outcome was the number of patients with 180 days follow-up with moderate or severe complications; secondary outcomes were postoperative length of stay, and specific complications. Data were extracted from patient records. Results There were 360 patients in the Pre-ERAS group and 319 patients in the Post-ERAS Group. 214 (59.8%) patients developed at least one complication in the pre ERAS group, versus 163 patients in the Post-ERAS group (51.10%). More patients in the Pre-ERAS group developed moderate or severe complications (31.9% vs. 22.26%, p = 0.009); and severe complications (15.5% vs. 5.3%; p < 0.0001). The median length of stay was 13 (17) days in Pre-ERAS Group and 11 (10) days in the Post-ERAS Group (p = 0.034). No differences were found on mortality rates (4.7% vs. 2.5%; p = 0.154), or readmission (6.39% vs. 4.39%; p = 0.31). Overall ERAS protocol compliance in the Post-ERAS cohort was 88%. Conclusions The implementation of ERAS protocol for colorectal surgery was associated with a significantly reduction of postoperative complications and length of stay.

Resumo Justificativa O protocolo ERAS - do Inglês Enhanced Recovery After Surgery - consiste em um conjunto de medidas perioperatórias destinadas a melhorar a recuperação do paciente e diminuir o tempo de internação e as complicações pós-operatórias. Avaliamos a implantação e os resultados de um protocolo ERAS para cirurgia colorretal. Métodos Estudo observacional em centro único. Os dados foram coletados de pacientes consecutivos submetidos à cirurgia colorretal aberta ou laparoscópica durante dois períodos: três anos antes (pré-ERAS) e dois anos após (pós-ERAS) a implantação de um protocolo ERAS. As características basais de ambos os grupos foram comparadas. O desfecho primário foi o número de pacientes com 180 dias de acompanhamento com complicações moderadas ou graves. Os desfechos secundários foram tempo de internação pós-cirurgia e complicações específicas. Os dados foram extraídos de prontuários dos pacientes. Resultados O grupo pré-ERAS foi composto por 360 pacientes e o grupo pós-ERAS por 319. No grupo pré ERAS, 214 pacientes (59,8%) desenvolveram pelo menos uma complicação versus 163 (51,10%) no grupo pós-ERAS. Um número maior de pacientes do grupo pré-ERAS desenvolveu complicações moderadas ou graves (31,9% vs. 22,26%, p = 0,009); e complicações graves (15,5% vs. 5,3%; p < 0,0001). A mediana do tempo de internação foi de 13 (17) dias no grupo pré-ERAS e de 11 (10) dias no grupo pós-ERAS (p = 0,034). Não houve diferença nas taxas de mortalidade (4,7% vs. 2,5%; p = 0,1554) ou de reinternação (6,39% vs. 4,39%; p = 0,31). A conformidade geral do protocolo ERAS na coorte pós-ERAS foi de 88%. Conclusões A implantação do protocolo ERAS para cirurgia colorretal foi associada a uma redução significativa das complicações pós-operatórias e do tempo de internação.

[Enhanced recovery after surgery protocol versus conventional perioperative care in colorectal surgery. A single center cohort study]. / Aceleração da recuperação após protocolo cirúrgico versus cuidados perioperatórios convencionais em cirurgia colorretal. Um estudo de coorte em centro único.

BACKGROUND: Enhanced recovery after surgery (ERAS) protocols consist of a set of perioperative measures aimed at improving patient recovery and decreasing length of stay and postoperative complications. We assess the implementation and outcomes of an ERAS program for colorectal surgery. METHODS: Single center observational study. Data were collected from consecutive patients undergoing open or laparoscopic colorectal surgery during 2 time periods, 3 years before (Pre-ERAS) and 2 years after (Post-ERAS) the implementation of an ERAS protocol. Baseline characteristics of both groups were compared. The primary outcome was the number of patients with 180 days follow-up with moderate or severe complications; secondary outcomes were postoperative length of stay, and specific complications. Data were extracted from patient records. RESULTS: There were 360 patients in the Pre-ERAS group and 319 patients in the Post-ERAS Group. 214 (59.8%) patients developed at least one complication in the pre ERAS group, versus 163 patients in the Post-ERAS group (51.10%). More patients in the Pre-ERAS group developed moderate or severe complications (31.9% vs. 22.26%, p=0.009); and severe complications (15.5% vs. 5.3%; p<0.0001). The median length of stay was 13 (17) days in Pre-ERAS Group and 11 (10) days in the Post-ERAS Group (p=0.034). No differences were found on mortality rates (4.7% vs. 2.5%; p=0.154), or readmission (6.39% vs. 4.39%; p=0.31). Overall ERAS protocol compliance in the Post-ERAS cohort was 88%. CONCLUSIONS: The implementation of ERAS protocol for colorectal surgery was associated with a significantly reduction of postoperative complications and length of stay.

Potential negative effects of anti-histamines on male reproductive function.

Histamine (HA) is a pleiotropic biogenic amine synthesized exclusively by histidine decarboxylase (HDC) in most mammalian tissues. The literature on the role of HA within the male gonad has expanded over the last years, attracting attention to potential unexpected side-effects of anti-histamines on testicular function. In this regard, HA receptors (HRH1, HRH2 and HRH4) have been described in Leydig cells of different species, including human. Via these receptors, HA has been reported to trigger positive or negative interactions with the LH/hCG signaling pathway depending upon its concentration, thereby contributing to the local control of testicular androgen levels. It should then be considered that anti-histamines may affect testicular homeostasis by increasing or decreasing steroid production. Additionally, HRH1 and HRH2 receptors are present in peritubular and germ cells, and HRH2 antagonists have been found to negatively affect peritubular cells and reduce sperm viability. The potential negative impact of anti-histamines on male reproduction becomes even more dramatic if we consider that HA has also been associated with human sexual behavior and penile erection. What is more, although testicular mast cells are the major source of locally produced HA, recent studies have described HDC expression in macrophages, Leydig cells and germ cells, revealing the existence of multiple sources of HA within the testis. Undoubtedly, the more we learn about the testicular histaminergic system, the more opportunities there will be for rational design of drugs aimed at treating HA-related pathologies, with minimum or nule negative impact on fertility.

Histamine H4 receptor as a novel therapeutic target for the treatment of Leydig-cell tumours in prepubertal boys.

Leydig-cell tumours (LCTs) are rare endocrine tumours of the testicular interstitium, with recent increased incidence. Symptoms include precocious puberty in children; and erectile dysfunction, infertility and/or gynaecomastia, in adults. So far, scientific evidence points to aromatase (CYP19) overexpression and excessive oestrogen and insulin-like growth factor (IGF) -1 production as responsible for Leydig-cell tumourigenesis. LCTs are usually benign; however, malignant LCTs respond poorly to chemo/radiotherapy, highlighting the need to identify novel targets for treatment. Herein, we investigated the potential role of the histamine receptor H4 (HRH4) as a therapeutic target for LCTs using R2C rat Leydig tumour cells, a well-documented in vitro model for Leydigioma. Also, we studied for the first time the expression of CYP19, IGF-1R, oestrogen receptor (ER) α, ERß, androgen receptor (AR) and HRH4 in human prepubertal LCTs versus normal prepubertal testes (NPTs). HRH4 agonist treatment inhibited steroidogenesis and proliferation in R2C cells and also negatively affected their pro-angiogenic capacity in vitro and in vivo, as assessed by evaluating the proliferative activity of human umbilical vein endothelial cells and by means of the quail chorioallantoic membrane assay, respectively. Moreover, E2 and IGF-1 inhibited HRH4 mRNA and protein levels. In human prepubertal LCTs, CYP19, IGF-1R, ERα and ERß were overexpressed compared with NPTs. In contrast, HRH4 staining was weak in LCTs, but moderate/strong and confined to the interstitium in NPTs. Importantly, HRH4 was absent or barely detectable in seminiferous tubules or germ cells. Overall, our results point to HRH4 as a novel therapeutic target in LCTs.

Evaluación de polimorfismos genéticos protrombóticos y alteraciones del sistema fibrinolítico en mujeres con historia de complicaciones obstétricas / Prothrombotics Evaluation of genetic polymorphisms and fibrinolytic system alterations in women with a history of obstetric complications

La presencia de polimorfismos protrombóticos y algunas alteraciones fibrinolíticas han sido descriptas en las pacientes con pérdidas de embarazos (PE) recurrentes si bien no hay datos concluyentes al respecto y menos aún en pacientes con falla de implantación. El objetivo del trabajo fue en primer lugar analizar la prevalencia de 3 polimorfismos protrombóticos [Factor V Leiden, Polimorfismo del gen de la Protrombina 20210 (PT 20210) y polimorfismo del promotor del PAI 1 (4G5G)] en 147 pacientes con historia de PE comparados con un grupo control de mujeres sanas con historia de embarazos sin complicaciones. En segundo lugar, analizar la correlación entre 3 pruebas del sistema fibrínolítico: PAI 1 inmunológico, Lisis de euglobulinas (LE) pre y post isquemia y polimorfismo del PAI 1 4G5G en un grupo de 92 mujeres con historia de PE (n=49) o fallas de implantación (FI) post procedimientos de fertilización in vitro ( n=43). La prevalencia de los polimorfismos protrombóticos estudiados en las pacientes no fue significativamente diferente de la hallada en el grupo control normal, excepto para el Factor V Leiden en PE tardías (p=0.03) y sólo una tendencia para el PAI 4G4G en abortos tempranos recurrentes (p=0.08). La respuesta en la LE post isquemia fue mala en el 17.4% y ligeramente alterada en el 19.3%. Considerando a la población total de 92 mujeres con complicaciones obstétricas, no existió relación entre los niveles de PAlIo la respuesta fibrinolitica a la isquemia con el genotipo del promotor del PAI. Los niveles de PAI 1 estuvieron significativamente más elevados en las mujeres que presentaban factores de riesgo clásico de enfermedad cardiovascular (32.46 vs. 20.6 ng/rol, p=0.023), y esto fue especialmente debido al grupo de portadoras del genotipo homocigota 4G4G. Los niveles de PAI 1 y las LE pre y post isquemia presentaron correlación positiva con el índice de masa corporal...

Evaluación de polimorfismos genéticos protrombóticos y alteraciones del sistema fibrinolítico en mujeres con historia de complicaciones obstétricas / Prothrombotics Evaluation of genetic polymorphisms and fibrinolytic system alterations in women with a history of obstetric complications

La presencia de polimorfismos protrombóticos y algunas alteraciones fibrinolíticas han sido descriptas en las pacientes con pérdidas de embarazos (PE) recurrentes si bien no hay datos concluyentes al respecto y menos aún en pacientes con falla de implantación. El objetivo del trabajo fue en primer lugar analizar la prevalencia de 3 polimorfismos protrombóticos [Factor V Leiden, Polimorfismo del gen de la Protrombina 20210 (PT 20210) y polimorfismo del promotor del PAI 1 (4G5G)] en 147 pacientes con historia de PE comparados con un grupo control de mujeres sanas con historia de embarazos sin complicaciones. En segundo lugar, analizar la correlación entre 3 pruebas del sistema fibrínolítico: PAI 1 inmunológico, Lisis de euglobulinas (LE) pre y post isquemia y polimorfismo del PAI 1 4G5G en un grupo de 92 mujeres con historia de PE (n=49) o fallas de implantación (FI) post procedimientos de fertilización in vitro ( n=43). La prevalencia de los polimorfismos protrombóticos estudiados en las pacientes no fue significativamente diferente de la hallada en el grupo control normal, excepto para el Factor V Leiden en PE tardías (p=0.03) y sólo una tendencia para el PAI 4G4G en abortos tempranos recurrentes (p=0.08). La respuesta en la LE post isquemia fue mala en el 17.4% y ligeramente alterada en el 19.3%. Considerando a la población total de 92 mujeres con complicaciones obstétricas, no existió relación entre los niveles de PAlIo la respuesta fibrinolitica a la isquemia con el genotipo del promotor del PAI. Los niveles de PAI 1 estuvieron significativamente más elevados en las mujeres que presentaban factores de riesgo clásico de enfermedad cardiovascular (32.46 vs. 20.6 ng/rol, p=0.023), y esto fue especialmente debido al grupo de portadoras del genotipo homocigota 4G4G. Los niveles de PAI 1 y las LE pre y post isquemia presentaron correlación positiva con el índice de masa corporal...(AU)

Thrombophilia in human immunodeficiency virus-infected patients with osteonecrosis: Is there a real connection? The first case-control study.

Several reports have described an increased incidence of osteonecrosis in human immunodeficiency virus-infected patients (HIV+), but the cause has not been established. The association between thrombophilia and osteonecrosis in HIV+ was studied. A case-control study in HIV+, 19 cases and 38 controls, was designed. Magnetic resonance imaging was made in both groups to confirm or exclude hip osteonecrosis. The extensive tests of thrombophilia were measured, and the clinical data were recorded, nadir of CD4(+) cell count and well-known risk factors for osteonecrosis. Thrombophilia has been frequently found both in patients with and without osteonecrosis (thrombophilia, 68.4% vs 60.5%), but no specific thrombophilia tests were significantly associated with osteonecrosis. A low nadir of CD4(+) (<60 cells/microL) and corticoid use were significantly (P < .05) associated with osteonecrosis. In multivariate analysis, only nadir of CD4(+) <60 cells/microL remained a predictor of osteonecrosis (odds ratio = 7.33; 95% confidence interval, 1.80-29.82, P = .005). Thrombophilia might have a limited role in the development of osteonecrosis in HIV+. Nadir of CD4(+) <60 cells/microL and corticoid use were main factors.