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1.
Nat Commun ; 15(1): 7288, 2024 Aug 24.
Article in English | MEDLINE | ID: mdl-39179644

ABSTRACT

Correctly identifying perturbed biological pathways is a critical step in uncovering basic disease mechanisms and developing much-needed therapeutic strategies. However, whether current tools are optimal for unbiased discovery of relevant pathways remains unclear. Here, we create "Benchmark" to critically evaluate existing tools and find that most function sub-optimally. We thus develop the "Pathway Ensemble Tool" (PET), which outperforms existing methods. Deploying PET, we identify prognostic pathways across 12 cancer types. PET-identified prognostic pathways offer additional insights, with genes within these pathways serving as reliable biomarkers for clinical outcomes. Additionally, normalizing these pathways using drug repurposing strategies represents therapeutic opportunities. For example, the top predicted repurposed drug for bladder cancer, a CDK2/9 inhibitor, represses cell growth in vitro and in vivo. We anticipate that using Benchmark and PET for unbiased pathway discovery will offer additional insights into disease mechanisms across a spectrum of diseases, enabling biomarker discovery and therapeutic strategies.


Subject(s)
Benchmarking , Neoplasms , Humans , Neoplasms/drug therapy , Neoplasms/metabolism , Neoplasms/genetics , Signal Transduction/drug effects , Biomarkers, Tumor/metabolism , Biomarkers, Tumor/genetics , Drug Repositioning , Animals , Prognosis , Antineoplastic Agents/pharmacology , Antineoplastic Agents/therapeutic use , Cell Line, Tumor , Computational Biology/methods , Mice
2.
Mol Cancer Res ; 22(9): 879-890, 2024 Sep 04.
Article in English | MEDLINE | ID: mdl-38771248

ABSTRACT

Angiosarcoma is a vascular sarcoma that is highly aggressive and metastatic. Because of its rarity, treatment options for patients are limited. Therefore, more research is needed to identify possible therapeutic vulnerabilities. We previously found that conditional deletion of Dicer1 drives angiosarcoma development in mice. Given the role of DICER1 in canonical miRNA biogenesis, this suggests that miRNA loss is important in angiosarcoma development. After testing miRNAs previously suggested to have a tumor-suppressive role in angiosarcoma, miRNA-497-5p (miR-497) suppressed cell viability most significantly. We also found that miR-497 overexpression led to significantly reduced cell migration and tumor formation. To understand the mechanism of miR-497 in tumor suppression, we identified clinically relevant target genes using a combination of RNA-sequencing data in an angiosarcoma cell line, expression data from patients with angiosarcoma, and target prediction algorithms. We validated miR-497 direct regulation of cyclin-D2, cyclin-dependent kinase 6, and vesicle amine transport protein 1 (VAT1). One of these genes, VAT1, is an understudied protein that has been suggested to promote cell migration and metastasis in other cancers. Indeed, we find that pharmacologic inhibition of VAT1 with the natural product neocarzilin A reduces angiosarcoma migration. Implications: This work supports the potent tumor-suppressive abilities of miR-497 in angiosarcoma, providing evidence for its potential as a therapeutic agent, and provides insight into the mechanisms of tumor suppression through analysis of the target gene regulatory network of miR-497.


Subject(s)
Gene Regulatory Networks , Hemangiosarcoma , MicroRNAs , MicroRNAs/genetics , Humans , Hemangiosarcoma/genetics , Hemangiosarcoma/pathology , Mice , Animals , Gene Expression Regulation, Neoplastic , Cell Line, Tumor , Cell Movement/genetics
3.
bioRxiv ; 2023 Sep 25.
Article in English | MEDLINE | ID: mdl-37808715

ABSTRACT

Angiosarcoma (AS) is a vascular sarcoma that is highly aggressive and metastatic. Due to its rarity, treatment options for patients are limited, therefore more research is needed to identify possible therapeutic vulnerabilities. We previously found that conditional deletion of Dicer1 drives AS development in mice. Given the role of DICER1 in canonical microRNA (miRNA) biogenesis, this suggests that miRNA loss is important in AS development. After testing miRNAs previously suggested to have a tumor-suppressive role in AS, microRNA-497-5p (miR-497) suppressed cell viability most significantly. We also found that miR-497 overexpression led to significantly reduced cell migration and tumor formation. To understand the mechanism of miR-497 in tumor suppression, we identified clinically relevant target genes using a combination of RNA-sequencing data in an AS cell line, expression data from AS patients, and target prediction algorithms. We validated miR-497 direct regulation of CCND2, CDK6, and VAT1. One of these genes, VAT1, is an understudied protein that has been suggested to promote cell migration and metastasis in other cancers. Indeed, we find that pharmacologic inhibition of VAT1 with the natural product Neocarzilin A reduces AS migration. This work provides insight into the mechanisms of miR-497 and its target genes in AS pathogenesis.

4.
J Pathol ; 257(1): 109-124, 2022 05.
Article in English | MEDLINE | ID: mdl-35066877

ABSTRACT

Angiosarcomas are aggressive vascular sarcomas that arise from endothelial cells and have an extremely poor prognosis. Because of the rarity of angiosarcomas, knowledge of molecular drivers and optimized treatment strategies is lacking, highlighting the need for in vivo models to study the disease. Previously, we generated genetically engineered mouse models of angiosarcoma driven by aP2-Cre-mediated biallelic loss of Dicer1 or conditional activation of KrasG12D with Cdkn2a loss that histologically and genetically resemble human tumors. In the present study, we found that DICER1 functions as a potent tumor suppressor and its deletion, in combination with either KRASG12D expression or Cdkn2a loss, is associated with angiosarcoma development. Independent of the genetic driver, the mTOR pathway was activated in all murine angiosarcoma models. Direct activation of the mTOR pathway by conditional deletion of Tsc1 with aP2-Cre resulted in tumors that resemble intermediate grade human kaposiform hemangioendotheliomas, indicating that mTOR activation was not sufficient to drive the malignant angiosarcoma phenotype. Genetic dissection of the spectrum of vascular tumors identified genes specifically regulated in the aggressive murine angiosarcomas that are also enriched in human angiosarcoma. The genetic dissection driving the transition across the malignant spectrum of endothelial sarcomas provides an opportunity to identify key determinants of the malignant phenotype, novel therapies for angiosarcoma, and novel in vivo models to further explore angiosarcoma pathogenesis. © 2022 The Authors. The Journal of Pathology published by John Wiley & Sons Ltd on behalf of The Pathological Society of Great Britain and Ireland.


Subject(s)
Hemangiosarcoma , Soft Tissue Neoplasms , Animals , Carcinogenesis , Endothelial Cells/metabolism , Hemangiosarcoma/genetics , Hemangiosarcoma/pathology , Integrases , Mice , Proto-Oncogene Proteins p21(ras)/metabolism , TOR Serine-Threonine Kinases/metabolism
5.
Nat Commun ; 12(1): 5520, 2021 09 17.
Article in English | MEDLINE | ID: mdl-34535684

ABSTRACT

PTEN promoter hypermethylation is nearly universal and PTEN copy number loss occurs in ~25% of fusion-negative rhabdomyosarcoma (FN-RMS). Here we show Pten deletion in a mouse model of FN-RMS results in less differentiated tumors more closely resembling human embryonal RMS. PTEN loss activated the PI3K pathway but did not increase mTOR activity. In wild-type tumors, PTEN was expressed in the nucleus suggesting loss of nuclear PTEN functions could account for these phenotypes. Pten deleted tumors had increased expression of transcription factors important in neural and skeletal muscle development including Dbx1 and Pax7. Pax7 deletion completely rescued the effects of Pten loss. Strikingly, these Pten;Pax7 deleted tumors were no longer FN-RMS but displayed smooth muscle differentiation similar to leiomyosarcoma. These data highlight how Pten loss in FN-RMS is connected to a PAX7 lineage-specific transcriptional output that creates a dependency or synthetic essentiality on the transcription factor PAX7 to maintain tumor identity.


Subject(s)
PAX7 Transcription Factor/metabolism , PTEN Phosphohydrolase/metabolism , Rhabdomyosarcoma/metabolism , Rhabdomyosarcoma/pathology , Animals , Breeding , Cell Differentiation , Cell Line, Tumor , Gene Expression Regulation, Neoplastic , Homeodomain Proteins/metabolism , Humans , Integrases/metabolism , Mechanistic Target of Rapamycin Complex 1/metabolism , Mice, Knockout , Muscle Development , PTEN Phosphohydrolase/deficiency , Phosphoproteins/metabolism , Proto-Oncogene Proteins c-akt/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Rhabdomyosarcoma/genetics
6.
Ann Med Surg (Lond) ; 65: 102259, 2021 May.
Article in English | MEDLINE | ID: mdl-33996042

ABSTRACT

INTRODUCTION: The hallux valgus deformity is a complex deformity of the first ray of the foot, with more than 100 procedures developed for its treatment. The aim of this retrospective study was to assess the clinical and radiographic outcomes of a modified Mitchell's technique. METHODS: Between 2007 and 2018, 75 patients underwent the procedure. Clinical results were assessed by the AOFAS score. Radiological studies were evaluated by measuring pre-operative and post-operative HVA and IMA angles as well as the relative shortening of the first metatarsal. RESULTS: Of the initial 75 patients, 42 patients remained eligible with a total of 67 feet. The mean age and follow-up were 47.8 and 5.2 years respectively. Global AOFAS score improved from 45.3 to 88.8 (p < 0.01). Mean HVA and IMA improved from 37.0 to 10.2 (p < 0,01) and 12.1 to 5.6 (p < 0.01), respectively. The mean metatarsal shortening was 3.0 mm (p < 0.01). The statistical analysis showed no significant correlation between preoperative HVA and IMA angles with postoperative shortening, metatarsalgia, AOFAS scores nor the difference between the preoperative and postoperative AOFAS scores. CONCLUSION: Short- and long-term outcomes of this modified Mitchell's osteotomy have been reported. Compared to other studies, these modifications proved to result in very good clinical and radiological outcomes even in severe cases with HVA>40. It has shown to be reliable, reproducible, and cost-efficient with low complication rates. We would like to highlight the importance of proper patient selection, limited soft tissue stripping, and adherence to the proposed surgical steps to avoid unwanted complications.

7.
Oncology ; 99(9): 580-588, 2021.
Article in English | MEDLINE | ID: mdl-33957633

ABSTRACT

PURPOSE: Glioblastoma, the most common malignant brain tumor, was associated with a median survival of <1 year in the pre-temozolomide (TMZ) era. Despite advances in molecular and genetic profiling studies identifying several predictive biomarkers, none has been translated into routine clinical use. Our aim was to investigate the prognostic significance of a panel of diverse cellular molecular markers of tumor formation and growth in an annotated glioblastoma tissue microarray (TMA). METHODS AND MATERIALS: A TMA composed of archived glioblastoma tumors from patients treated with surgery, radiation, and non-TMZ chemother-apy, was provided by RTOG. RAD51, BRCA-1, phosphatase and tensin homolog tumor suppressor gene (PTEN), and miRNA-210 expression levels were assessed using quantitative in situ hybridization and automated quantitative protein analysis. The objectives of this analysis were to determine the association of each biomarker with overall survival (OS), using the Cox proportional hazard model. Event-time distributions were estimated using the Kaplan-Meier method and compared by the log-rank test. RESULTS: A cohort of 66 patients was included in this study. Among the 4 biomarkers assessed, only BRCA1 expression had a statistically significant correlation with survival. From univariate analysis, patients with low BRCA1 protein expression showed a favorable outcome for OS (p = 0.04; hazard ratio = 0.56) in comparison with high expressors, with a median survival time of 18.9 versus 4.8 months. CONCLUSIONS: BRCA1 protein expression was an important survival predictor in our cohort of glioblastoma patients. This result may imply that low BRCA1 in the tumor and the consequent low level of DNA repair cause vulnerability of the cancer cells to treatment.


Subject(s)
BRCA1 Protein/metabolism , Brain Neoplasms/metabolism , Glioblastoma/metabolism , Adolescent , Adult , Aged , Biomarkers, Tumor/metabolism , Brain Neoplasms/pathology , Brain Neoplasms/therapy , Cohort Studies , Combined Modality Therapy , Female , Glioblastoma/pathology , Glioblastoma/therapy , Humans , Kaplan-Meier Estimate , Male , Middle Aged , Proportional Hazards Models , Tissue Array Analysis , Young Adult
8.
Front Microbiol ; 10: 1941, 2019.
Article in English | MEDLINE | ID: mdl-31507558

ABSTRACT

In the last decade, extended-spectrum cephalosporin and carbapenem resistant Gram-negative bacilli (GNB) have been extensively reported in the literature as being disseminated in humans but also in animals and the environment. These resistant organisms often cause treatment challenges due to their wide spectrum of antibiotic resistance. With the emergence of colistin resistance in animals and its subsequent detection in humans, the situation has worsened. Several studies reported the transmission of resistant organisms from animals to humans. Studies from the middle east highlight the spread of resistant organisms in hospitals and to a lesser extent in livestock and the environment. In view of the recent socio-economical conflicts that these countries are facing in addition to the constant population mobilization; we attempt in this review to highlight the gaps of the prevalence of resistance, antibiotic consumption reports, infection control measures and other risk factors contributing in particular to the spread of resistance in these countries. In hospitals, carbapenemases producers appear to be dominant. In contrast, extended spectrum beta lactamases (ESBL) and colistin resistance are becoming a serious problem in animals. This is mainly due to the continuous use of colistin in veterinary medicine even though it is now abandoned in the human sphere. In the environment, despite the small number of reports, ESBL and carbapenemases producers were both detected. This highlights the importance of the latter as a bridge between humans and animals in the transmission chain. In this review, we note that in the majority of the Middle Eastern area, little is known about the level of antibiotic consumption especially in the community and animal farms. Furthermore, some countries are currently facing issues with immigrants, poverty and poor living conditions which has been imposed by the civil war crisis. This all greatly facilitates the dissemination of resistance in all environments. In the one health concept, this work re-emphasizes the need to have global intervention measures to avoid dissemination of antibiotic resistance in humans, animals and the environment in Middle Eastern countries.

9.
Bioethics ; 33(2): 267-273, 2019 02.
Article in English | MEDLINE | ID: mdl-30480852

ABSTRACT

According to the causal theory of parenthood, people incur parental obligations by causing children to exist. Proponents of the causal theory often argue that gamete donors have special obligations to their genetic offspring. In response, many defenders of current gamete donation practices would reject the causal theory. In particular, they may invoke the 'too many parents problem': many people who causally contribute to the existence of children - for instance, fertility doctors - do not thereby incur parental obligations. This article argues that the conclusions commonly drawn by causal theorists, and by their critics, are premature. Causal theorists have a promising response to the too many parents problem. This response, however, defuses the moral concern that many causal theorists have raised about gamete donation. A similar point, it is argued, applies to Rivka Weinberg's 'Hazmat Theory'.


Subject(s)
Donor Conception/ethics , Germ Cells , Moral Obligations , Parent-Child Relations , Parents , Reproduction/ethics , Tissue Donors/ethics , Adult , Bioethical Issues , Child , Dissent and Disputes , Female , Humans , Male , Physicians/ethics , Spermatozoa , Tissue and Organ Procurement
10.
Cancer Cell ; 33(1): 108-124.e5, 2018 01 08.
Article in English | MEDLINE | ID: mdl-29316425

ABSTRACT

Rhabdomyosarcoma (RMS) is a pediatric soft tissue sarcoma that histologically resembles embryonic skeletal muscle. RMS occurs throughout the body and an exclusively myogenic origin does not account for RMS occurring in sites devoid of skeletal muscle. We previously described an RMS model activating a conditional constitutively active Smoothened mutant (SmoM2) with aP2-Cre. Using genetic fate mapping, we show SmoM2 expression in Cre-expressing endothelial progenitors results in myogenic transdifferentiation and RMS. We show that endothelium and skeletal muscle within the head and neck arise from Kdr-expressing progenitors, and that hedgehog pathway activation results in aberrant expression of myogenic specification factors as a potential mechanism driving RMS genesis. These findings suggest that RMS can originate from aberrant development of non-myogenic cells.


Subject(s)
Endothelium/metabolism , Hedgehog Proteins/metabolism , Muscle Development/genetics , Rhabdomyosarcoma/metabolism , Stem Cells/metabolism , Animals , Cell Differentiation/physiology , Mice, Transgenic , Muscle, Skeletal/metabolism , Signal Transduction
11.
Oncogene ; 37(15): 1991-2007, 2018 04.
Article in English | MEDLINE | ID: mdl-29367756

ABSTRACT

Rhabdomyosarcoma is the most common soft-tissue sarcoma in childhood and histologically resembles developing skeletal muscle. Alveolar rhabdomyosarcoma (ARMS) is an aggressive subtype with a higher rate of metastasis and poorer prognosis. The majority of ARMS tumors (80%) harbor a PAX3-FOXO1 or less commonly a PAX7-FOXO1 fusion gene. The presence of either the PAX3-FOXO1 or PAX7-FOXO1 fusion gene foretells a poorer prognosis resulting in clinical re-classification as either fusion-positive (FP-RMS) or fusion-negative RMS (FN-RMS). The PAX3/7-FOXO1 fusion genes result in the production of a rogue transcription factors that drive FP-RMS pathogenesis and block myogenic differentiation. Despite knowing the molecular driver of FP-RMS, targeted therapies have yet to make an impact for patients, highlighting the need for a greater understanding of the molecular consequences of PAX3-FOXO1 and its target genes including microRNAs. Here we show FP-RMS patient-derived xenografts and cell lines display a distinct microRNA expression pattern. We utilized both loss- and gain-of function approaches in human cell lines with knockdown of PAX3-FOXO1 in FP-RMS cell lines and expression of PAX3-FOXO1 in human myoblasts and identified microRNAs both positively and negatively regulated by the PAX3-FOXO1 fusion protein. We demonstrate PAX3-FOXO1 represses miR-221/222 that functions as a tumor suppressing microRNA through the negative regulation of CCND2, CDK6, and ERBB3. In contrast, miR-486-5p is transcriptionally activated by PAX3-FOXO1 and promotes FP-RMS proliferation, invasion, and clonogenic growth. Inhibition of miR-486-5p in FP-RMS xenografts decreased tumor growth, illustrating a proof of principle for future therapeutic intervention. Therefore, PAX3-FOXO1 regulates key microRNAs that may represent novel therapeutic vulnerabilities in FP-RMS.


Subject(s)
MicroRNAs/genetics , Muscle Neoplasms/genetics , Oncogene Proteins, Fusion/physiology , Paired Box Transcription Factors/physiology , Rhabdomyosarcoma, Alveolar/genetics , Animals , Cell Proliferation/genetics , Cell Transformation, Neoplastic/genetics , Cells, Cultured , Child , Female , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Gene Knockdown Techniques , HEK293 Cells , Humans , Mice , Mice, SCID , Microarray Analysis , Muscle Neoplasms/pathology , Oncogene Proteins, Fusion/genetics , Paired Box Transcription Factors/genetics , Rhabdomyosarcoma, Alveolar/pathology
12.
Cancer Res ; 77(22): 6109-6118, 2017 11 15.
Article in English | MEDLINE | ID: mdl-28916654

ABSTRACT

Angiosarcoma is an aggressive vascular sarcoma with an extremely poor prognosis. Because of the relative rarity of this disease, its molecular drivers and optimal treatment strategies are obscure. DICER1 is an RNase III endoribonuclease central to miRNA biogenesis, and germline DICER1 mutations result in a cancer predisposition syndrome, associated with an increased risk of many tumor types. Here, we show that biallelic Dicer1 deletion with aP2-Cre drives aggressive and metastatic angiosarcoma independent of other genetically engineered oncogenes or tumor suppressor loss. Angiosarcomas in aP2-Cre;Dicer1Flox/- mice histologically and genetically resemble human angiosarcoma. miR-23 target genes, including the oncogenes Ccnd1 as well as Adam19, Plau, and Wsb1 that promote invasiveness and metastasis, were enriched in mouse and human angiosarcoma. These studies illustrate that Dicer1 can function as a traditional loss-of-function tumor suppressor gene, and they provide a fully penetrant animal model for the study of angiosarcoma development and metastasis. Cancer Res; 77(22); 6109-18. ©2017 AACR.


Subject(s)
DEAD-box RNA Helicases/genetics , Genetic Predisposition to Disease/genetics , Hemangiosarcoma/genetics , Mutation , Ribonuclease III/genetics , Animals , Gene Expression Profiling/methods , Gene Expression Regulation, Neoplastic , Genes, Tumor Suppressor , Hemangiosarcoma/pathology , Homozygote , Humans , Kaplan-Meier Estimate , Mice, Knockout , Mice, Transgenic , MicroRNAs/genetics
13.
Orthopedics ; 38(2): 81-6, 2015 Feb.
Article in English | MEDLINE | ID: mdl-25665106

ABSTRACT

The goal of this study was to evaluate contact area and surface pressure as a result of different suture patterns in the treatment of anterior shoulder instability caused by a Bankart lesion. Loads were applied through the humeral head to the glenoid surface in the intact shoulder and after simple suture labral repair (n=10) and vertical mattress labral repair (n=9). Peak contact pressure, mean contact pressure, and contact area were recorded for 0°, 45°, and 90° shoulder abduction, and then the repair was loaded to failure. A significant increase (P<.05) in mean contact pressure and peak contact pressure occurred in both repair groups at 90° abduction. No difference was seen between the 2 repair groups. Total contact area significantly decreased after both repairs at 90° abduction at 220 N force (P<.05). No significant difference occurred in load to failure between the groups. Joint loading properties can be affected by alterations in contact pressure within the glenohumeral joint. In the current study, the authors found no significant difference in contact pressure between the 2 repair groups. However, they found a significant increase in mean contact pressure and peak pressure between the intact specimen and the 2 repair groups. Both simple repair and vertical mattress repair provided similar load to failure for labral repair. Current techniques used to perform Bankart repair may need to be altered to provide the stability of current techniques with more normal glenohumeral joint contact pressure.


Subject(s)
Humeral Head/surgery , Shoulder Joint/surgery , Shoulder/surgery , Suture Techniques , Biomechanical Phenomena , Humans , Weight-Bearing , Wound Healing
14.
Orthopedics ; 36(8): e1047-52, 2013 Aug.
Article in English | MEDLINE | ID: mdl-23937752

ABSTRACT

Methods to reconstruct the coracoclavicular ligaments anatomically have been described. No clear advantage of 1 technique has been elucidated. The authors' hypothesis was that the biomechanical properties of a modified knot fixation technique would be similar to the anatomical double-bundle technique. Sixteen matched cadaveric shoulders were used for this study, and 1 additional shoulder was used in the knot fixation group only. Shoulders were randomly assigned to the anatomical double-bundle coracoclavicular ligament reconstruction technique (n=8) or a knot fixation technique (n=9). The intact coracoclavicular ligaments were tested to failure with superior displacement at a rate of 2 mm/s. Reconstruction was performed using a semitendinosus tendon allograft, and load to failure was repeated for each construct. Ultimate failure load, stiffness, and failure mode were compared using a paired t test (P<.05). No significant difference existed in load to failure between native and reconstructed ligaments or between reconstruction techniques. Stiffness decreased significantly after reconstruction in the double-bundle group (from 32.5 to 22.5 N/mm; P=.035) and in the modified knot fixation group (from 35.5 to 21.9 N/mm; P=.043). No significant difference existed in stiffness between the 2 reconstruction groups. A significant difference (P=.003) existed between failure modes between the 2 reconstruction techniques. Although less stiff than the native ligament, either technique used to reconstruct the coracoclavicular ligament can be performed to yield a load to failure similar to the intact ligament. The majority of failures in the double-bundle group were by means of the graft slipping at the screw-tendon interface at 1 of the clavicular drill holes. The modified knot fixation technique failed the majority of the time by graft elongation.


Subject(s)
Acromioclavicular Joint , Bone Screws , Ligaments , Plastic Surgery Procedures/instrumentation , Suture Anchors , Suture Techniques/instrumentation , Acromioclavicular Joint/injuries , Acromioclavicular Joint/physiopathology , Acromioclavicular Joint/surgery , Aged , Aged, 80 and over , Cadaver , Elastic Modulus , Female , Humans , Internal Fixators , Ligaments/injuries , Ligaments/physiopathology , Ligaments/surgery , Male , Middle Aged , Stress, Mechanical , Tensile Strength , Treatment Outcome
15.
Am J Sports Med ; 41(2): 291-5, 2013 Feb.
Article in English | MEDLINE | ID: mdl-23271005

ABSTRACT

BACKGROUND: Treatment for acromioclavicular (AC) joint pain may include distal clavicle excision (DCE). It is possible that DCE can disrupt the surrounding ligaments, leading to increased AC joint laxity. PURPOSE: To determine the load to failure and stiffness of the AC joint after DCE and symmetric acromioclavicular joint resection (ACJR). STUDY DESIGN: Controlled laboratory study. METHODS: Specimens were randomly assigned to 1 of 2 groups: 1-cm DCE (n = 10) or symmetric (5-mm excision of acromion and distal clavicle) ACJR (n = 10). The specimens were loaded intact in the anterior-posterior plane to determine anteroposterior translation. This was repeated after surgery and compared. The specimens were loaded at 2 mm/s until clinical failure. Force and displacement were recorded, and stiffness was calculated. RESULTS: The peak load to failure for the DCE group was 387.8 N (standard error of the mean [SEM], 31.4 N) and for the ACJR group was 468.5 N (SEM, 30.9 N) (P = .035). The average stiffness for the DCE group was 35.2 N/mm (SEM, 2.5 N/mm) and for the ACJR group was 37.4 N/mm (SEM, 2.3 N/mm) (P = .11). There was no significant difference in the anteroposterior translation before and after resection for either group (P > .05). CONCLUSION: This cadaveric study demonstrates that the anterior-posterior load to clinical failure of the AC joint after 5 mm of resection from the distal clavicle and medial acromion is significantly greater than 1 cm of the resected distal clavicle alone. CLINICAL RELEVANCE: Performing ACJR may improve joint stability, leading to fewer complications when compared with DCE.


Subject(s)
Acromioclavicular Joint/surgery , Arthralgia/surgery , Clavicle/surgery , Joint Instability/physiopathology , Shoulder Joint/surgery , Acromioclavicular Joint/physiopathology , Aged , Biomechanical Phenomena , Cadaver , Clavicle/physiopathology , Female , Humans , Joint Instability/etiology , Male , Middle Aged , Shoulder Joint/physiopathology
16.
Lab Invest ; 92(10): 1390-7, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22890556

ABSTRACT

Oncogenic and tumor suppressing microRNAs (miRNAs) have emerged as key regulators of gene expression in many types of cancer including melanoma. We utilized quantitative in situ hybridization (qISH) to evaluate the tumor suppressing properties of miRNA, miR-205 in a population of human tumors. We hypothesize decreased miR-205 would be associated with more aggressive tumors. Multiplexing miR-205 qISH with immunofluorescent assessment of S100/GP100 allowed us to quantitatively evaluate miR-205 expression using the AQUA method of quantitative immunofluorescence. The specificity of the assay was validated using blocking oligos and transfected cell lines as controls. Outcomes were assessed on the Yale Melanoma Discovery Cohort consisting of 105 primary melanoma specimens and validated on an independent set of 206 primary melanomas (Yale Melanoma Validation Cohort). Measurement of melanoma cell miR-205 levels shows a significantly shorter melanoma-specific survival in patients with low expression. Multivariate analysis shows miR-205 levels are significantly independent of stage, age, gender, and Breslow depth. Low levels of melanoma cell miR-205 expression as quantified by ISH show worse outcome, supporting the role of miR-205 as a tumor suppressor miRNA. The quantification of miR-205 in situ suggests potential for the use of miRNAs in future prognostic or predictive models.


Subject(s)
Biomarkers, Tumor/analysis , In Situ Hybridization/methods , Melanoma/diagnosis , MicroRNAs/analysis , RNA, Neoplasm/analysis , Skin Neoplasms/diagnosis , Aged , Analysis of Variance , Biomarkers, Tumor/genetics , Cell Line, Tumor , Female , Gene Expression Profiling/methods , Gene Expression Regulation, Neoplastic/genetics , Humans , Male , Melanoma/pathology , MicroRNAs/genetics , Middle Aged , Prognosis , RNA, Neoplasm/genetics , Retrospective Studies , Reverse Transcriptase Polymerase Chain Reaction , S100 Proteins/immunology , S100 Proteins/metabolism , Skin Neoplasms/pathology , Tissue Array Analysis/methods , gp100 Melanoma Antigen/immunology , gp100 Melanoma Antigen/metabolism
17.
Cancer Discov ; 2(8): 736-49, 2012 Aug.
Article in English | MEDLINE | ID: mdl-22750848

ABSTRACT

UNLABELLED: Leveraging The Cancer Genome Atlas (TCGA) multidimensional data in glioblastoma, we inferred the putative regulatory network between microRNA and mRNA using the Context Likelihood of Relatedness modeling algorithm. Interrogation of the network in context of defined molecular subtypes identified 8 microRNAs with a strong discriminatory potential between proneural and mesenchymal subtypes. Integrative in silico analyses, a functional genetic screen, and experimental validation identified miR-34a as a tumor suppressor in proneural subtype glioblastoma. Mechanistically, in addition to its direct regulation of platelet-derived growth factor receptor-alpha (PDGFRA), promoter enrichment analysis of context likelihood of relatedness-inferred mRNA nodes established miR-34a as a novel regulator of a SMAD4 transcriptional network. Clinically, miR-34a expression level is shown to be prognostic, where miR-34a low-expressing glioblastomas exhibited better overall survival. This work illustrates the potential of comprehensive multidimensional cancer genomic data combined with computational and experimental models in enabling mechanistic exploration of relationships among different genetic elements across the genome space in cancer. SIGNIFICANCE: We illustrate here that network modeling of complex multidimensional cancer genomic data can generate a framework in which to explore the biology of cancers, leading to discovery of new pathogenetic insights as well as potential prognostic biomarkers. Specifically in glioblastoma, within the context of the global network, promoter enrichment analysis of network edges uncovered a novel regulation of TGF-ß signaling via a Smad4 transcriptomic network by miR-34a.


Subject(s)
Glioblastoma/genetics , MicroRNAs/genetics , Transforming Growth Factor beta/metabolism , Animals , Cell Line, Tumor , Gene Expression Regulation, Neoplastic , Gene Regulatory Networks , Genes, Tumor Suppressor , Glioblastoma/metabolism , Humans , Mice , MicroRNAs/metabolism , Prognosis , Signal Transduction , Transforming Growth Factor beta/genetics
18.
Biotechniques ; 52(4): 235-45, 2012 Apr.
Article in English | MEDLINE | ID: mdl-22482439

ABSTRACT

MicroRNAs (miRNAs) have emerged as key regulators in the pathogenesis of cancers where they can act as either oncogenes or tumor suppressors. Most miRNA measurement methods require total RNA extracts which lack critical spatial information and present challenges for standardization. We have developed and validated a method for the quantitative analysis of miRNA expression by in situ hybridization (ISH) allowing for the direct assessment of tumor epithelial expression of miRNAs. This co-localization based approach (called qISH) utilizes DAPI and cytokeratin immunofluorescence to establish subcellular compartments in the tumor epithelia, then multiplexed with the miRNA ISH, allows for quantitative measurement of miRNA expression within these compartments. We use this approach to assess miR-21, miR-92a, miR-34a, and miR-221 expression in 473 breast cancer specimens on tissue microarrays. We found that miR-221 levels are prognostic in breast cancer illustrating the high-throughput method and confirming that miRNAs can be valuable biomarkers in cancer. Furthermore, in applying this method we found that the inverse relationship between miRNAs and proposed target proteins is difficult to discern in large population cohorts. Our method demonstrates an approach for large cohort, tissue microarray-based assessment of miRNA expression.


Subject(s)
In Situ Hybridization/methods , MicroRNAs/metabolism , Tissue Array Analysis/methods , Animals , Breast Neoplasms/genetics , Cell Line, Tumor , Female , Humans , Mice , Mice, Knockout , MicroRNAs/genetics , Neoplasm Proteins/metabolism , Prognosis , Reproducibility of Results
19.
Cancer ; 118(19): 4660-9, 2012 Oct 01.
Article in English | MEDLINE | ID: mdl-22359235

ABSTRACT

BACKGROUND: Microtubule-associated proteins (MAPs) endogenously regulate microtubule stability. Here, the prognostic value of stathmin, a destabilizing protein, was assessed in combination with MAP-tau, a stabilizing protein, in order to evaluate microtubule stabilization as a potential biomarker. METHODS: Stathmin and MAP-tau expression levels were measured in a breast cancer cohort (n = 651) using the tissue microarray format and quantitative immunofluorescence (AQUA) technology, then correlated with clinical and pathological characteristics and disease-free survival. RESULTS: Univariate Cox proportional hazard models indicated that high stathmin expression predicts worse overall survival (hazard ratio [HR] = 1.48; 95% confidence interval [CI] = 1.119-1.966; P = .0061). Survival analysis showed 10-year survival of 53.1% for patients with high stathmin expression versus 67% for low expressers (log-rank, P < .003). Cox multivariate analysis showed high stathmin expression was independent of age, menopausal status, nodal status, nuclear grade, tumor size, and estrogen receptor, progesterone receptor, and human epidermal growth factor receptor 2 expression (HR = 1.19; 95% CI = 1.03-1.37; P = .01). The ratio of MAP-tau to stathmin expression showed a positive correlation to disease-free survival (HR = 0.679; 95% CI = 0.517-0.891; P = .0053) with a 10-year survival of 65.4% for patients who had a high ratio of MAP-tau to stathmin versus 52.5% 10-year survival rate for those with a low ratio (log-rank, P = .0009). Cox multivariate analysis showed the ratio of MAP-tau to stathmin was an independent predictor of overall survival (HR = 0.609; 95% CI = 0.422-0.879; P = .008). CONCLUSIONS: Low stathmin and high MAP-tau are associated with increased microtubule stability and better prognosis in breast cancer.


Subject(s)
Biomarkers, Tumor/analysis , Breast Neoplasms/chemistry , Stathmin/analysis , tau Proteins/analysis , Adult , Aged , Analysis of Variance , Blotting, Western , Breast/chemistry , Breast Neoplasms/mortality , Breast Neoplasms/pathology , Cell Line, Tumor , Cohort Studies , Female , Fluorescent Antibody Technique , Gene Expression Regulation, Neoplastic , Humans , Immunohistochemistry , Kaplan-Meier Estimate , Lymphatic Metastasis , Middle Aged , Neoplasm Grading , Neoplasm Staging , Odds Ratio , Predictive Value of Tests , Prognosis , Proportional Hazards Models , RNA, Small Interfering/metabolism , Risk Assessment , Risk Factors , Tissue Array Analysis , Treatment Outcome
20.
Cancer Cell ; 20(1): 92-103, 2011 Jul 12.
Article in English | MEDLINE | ID: mdl-21741599

ABSTRACT

Clinical and genomic evidence suggests that the metastatic potential of a primary tumor may be dictated by prometastatic events that have additional oncogenic capability. To test this "deterministic" hypothesis, we adopted a comparative oncogenomics-guided function-based strategy involving: (1) comparison of global transcriptomes of two genetically engineered mouse models with contrasting metastatic potential, (2) genomic and transcriptomic profiles of human melanoma, (3) functional genetic screen for enhancers of cell invasion, and (4) evidence of expression selection in human melanoma tissues. This integrated effort identified six genes that are potently proinvasive and oncogenic. Furthermore, we show that one such gene, ACP5, confers spontaneous metastasis in vivo, engages a key pathway governing metastasis, and is prognostic in human primary melanomas.


Subject(s)
Melanoma/genetics , Melanoma/pathology , Oncogenes/genetics , Skin Neoplasms/genetics , Skin Neoplasms/pathology , Acid Phosphatase/genetics , Acid Phosphatase/metabolism , Animals , Cell Lineage/genetics , Conserved Sequence/genetics , Evolution, Molecular , Gene Expression Profiling , Gene Expression Regulation, Neoplastic , Genome/genetics , Humans , Isoenzymes/genetics , Isoenzymes/metabolism , Kaplan-Meier Estimate , Mice , Neoplasm Invasiveness , Neoplasm Metastasis , Neoplasm Staging , Phosphorylation , Reproducibility of Results , Tartrate-Resistant Acid Phosphatase , Tissue Array Analysis
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