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Dive into the research topics where Paul J. Christos is active.

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Featured researches published by Paul J. Christos.


Cancer Cell | 2010

DNA Methylation Signatures Identify Biologically Distinct Subtypes in Acute Myeloid Leukemia

Maria E. Figueroa; Sanne Lugthart; Yushan Li; Claudia Erpelinck-Verschueren; Xutao Deng; Paul J. Christos; Elizabeth D. Schifano; James G. Booth; Wim L.J. van Putten; Lucy Skrabanek; Fabien Campagne; Madhu Mazumdar; John M. Greally; Peter J. M. Valk; Bob Löwenberg; Ruud Delwel; Ari Melnick

We hypothesized that DNA methylation distributes into specific patterns in cancer cells, which reflect critical biological differences. We therefore examined the methylation profiles of 344 patients with acute myeloid leukemia (AML). Clustering of these patients by methylation data segregated patients into 16 groups. Five of these groups defined new AML subtypes that shared no other known feature. In addition, DNA methylation profiles segregated patients with CEBPA aberrations from other subtypes of leukemia, defined four epigenetically distinct forms of AML with NPM1 mutations, and showed that established AML1-ETO, CBFb-MYH11, and PML-RARA leukemia entities are associated with specific methylation profiles. We report a 15 gene methylation classifier predictive of overall survival in an independent patient cohort (p < 0.001, adjusted for known covariates).


Human Gene Therapy | 2008

Treatment of Late Infantile Neuronal Ceroid Lipofuscinosis by CNS Administration of a Serotype 2 Adeno-Associated Virus Expressing CLN2 cDNA

Stefan Worgall; Dolan Sondhi; Neil R. Hackett; Barry E. Kosofsky; Minal V. Kekatpure; Nurunisa Neyzi; Jonathan P. Dyke; Douglas Ballon; Linda Heier; Bruce M. Greenwald; Paul J. Christos; Madhu Mazumdar; Mark M. Souweidane; Michael G. Kaplitt; Ronald G. Crystal

Late infantile neuronal ceroid lipofuscinosis (LINCL) is an autosomal recessive, neurodegenerative lysosomal storage disease affecting the CNS and is fatal by age 8 to 12 years. A total average dose of 2.5 10(12) particle units of an adeno-associated virus (AAV) serotype 2 vector expressing the human CLN2 cDNA (AAV2 CU h-CLN2) was administered to 12 locations in the CNS of 10 children with LINCL. In addition to safety parameters, a neurological rating scale (primary variable) and three quantitative magnetic resonance imaging (MRI) parameters (secondary variables) were used to compare the rate of neurological decline for 18 months in treated subjects compared with untreated subjects. Although there were no unexpected serious adverse events that were unequivocally attributable to the AAV2 CU hCLN2 vector, there were serious adverse effects, the etiology of which could not be determined under the conditions of the experiment. One subject died 49 days postsurgery after developing status epilepticus on day 14, but with no evidence of CNS inflammation. Four of the 10 subjects developed a mild, mostly transient, humoral response to the vector. Compared with control subjects, the measured rates of decline of all MRI parameters were slower, albeit the numbers were too small for statistical significance. Importantly, assessment of the neurologic rating scale, which was the primary outcome variable, demonstrated a significantly reduced rate of decline compared with control subjects. Although the trial is not matched, randomized, or blinded and lacked a contemporaneous placebo/sham control group, assessment of the primary outcome variable suggests a slowing of progression of LINCL in the treated children. On this basis, we propose that additional studies to assess the safety and efficacy of AAV-mediated gene therapy for LINCL are warranted.


PLOS ONE | 2012

Intra- and Inter-Tumor Heterogeneity of BRAFV600EMutations in Primary and Metastatic Melanoma

Molly Yancovitz; Adam J. Litterman; Joanne Yoon; Elise Ng; Richard L. Shapiro; Russell S. Berman; Anna C. Pavlick; Farbod Darvishian; Paul J. Christos; Madhu Mazumdar; Iman Osman; David Polsky

The rationale for using small molecule inhibitors of oncogenic proteins as cancer therapies depends, at least in part, on the assumption that metastatic tumors are primarily clonal with respect to mutant oncogene. With the emergence of BRAFV600E as a therapeutic target, we investigated intra- and inter-tumor heterogeneity in melanoma using detection of the BRAFV600E mutation as a marker of clonality. BRAF mutant-specific PCR (MS-PCR) and conventional sequencing were performed on 112 tumors from 73 patients, including patients with matched primary and metastatic specimens (n = 18). Nineteen patients had tissues available from multiple metastatic sites. Mutations were detected in 36/112 (32%) melanomas using conventional sequencing, and 85/112 (76%) using MS-PCR. The better sensitivity of the MS-PCR to detect the mutant BRAFV600E allele was not due to the presence of contaminating normal tissue, suggesting that the tumor was comprised of subclones of differing BRAF genotypes. To determine if tumor subclones were present in individual primary melanomas, we performed laser microdissection and mutation detection via sequencing and BRAFV600E-specific SNaPshot analysis in 9 cases. Six of these cases demonstrated differing proportions of BRAFV600Eand BRAFwild-type cells in distinct microdissected regions within individual tumors. Additional analyses of multiple metastatic samples from individual patients using the highly sensitive MS-PCR without microdissection revealed that 5/19 (26%) patients had metastases that were discordant for the BRAFV600E mutation. In conclusion, we used highly sensitive BRAF mutation detection methods and observed substantial evidence for heterogeneity of the BRAFV600E mutation within individual melanoma tumor specimens, and among multiple specimens from individual patients. Given the varied clinical responses of patients to BRAF inhibitor therapy, these data suggest that additional studies to determine possible associations between clinical outcomes and intra- and inter-tumor heterogeneity could prove fruitful.


Annals of Surgical Oncology | 1999

Local and distant recurrence rates in skin-sparing mastectomies compared with non-skin-sparing mastectomies.

Rache M. Simmons; Susan Kersey Fish; Lloyd B. Gayle; Gregory S. La Trenta; Alexander Swistel; Paul J. Christos; Michael P. Osborne

BACKGROUND Skin-sparing mastectomies (SSMs) are being used more frequently to treat many cases of breast cancer. This type of surgery maximizes breast skin preservation and facilitates immediate reconstruction, resulting in a superior cosmetic appearance after mastectomy and a more satisfied patient. Although SSMs are becoming more common, there are few data regarding the local and distant recurrence rates. METHODS A total of 231 patients treated with mastectomies from 1990 to 1998 were studied, including 77 SSM and 154 non-skin-sparing (NSSM) mastectomy patients. RESULTS The local recurrence rates for SSM and NSSM were 3.90% (3 of 77 patients) and 3.25% (5 of 154 patients), respectively. The local recurrence-free survival at 5 years was 95.3% for SSM patients and 95.2% for NSSM patients (P = .28). The distant recurrence rates of SSM and NSSM were 3.9% (3 of 77 patients) and 3.9% (6 of 154 patients), respectively. The distant recurrence-free actuarial survival at 5 years was 90.2% for SSM patients and 92% for NSSM patients (P = .07). CONCLUSIONS Mastectomies using the skin-sparing technique do not appear to result in any increase in local or distant recurrence and improve aesthetic results of the immediate reconstruction.


Annals of Surgical Oncology | 2002

Analysis of nipple/areolar involvement with mastectomy: Can the areola be preserved?

Rache M. Simmons; Meghan B. Brennan; Paul J. Christos; Valencia King; Michael P. Osborne

Skin-sparing mastectomy (SSM), which involves the resection of the nipple/areolar complex with the breast parenchyma, improves the aesthetic outcome for breast cancer patients. Most patients undergoing SSM desire reconstruction of the nipple/areolar complex for symmetry. These data explore the possibility of preserving the areola in selected mastectomy patients. A retrospective analysis of 217 mastectomy patients was conducted to determine the frequency of malignant nipple and/or areola involvement. The association between nipple and/or areola involvement and prognostic factors, including tumor size, stage, nuclear grade, axillary nodal status, and tumor location, was evaluated. The overall frequency of malignant nipple involvement was 23 of 217 (10.6%). In a subgroup of patients with tumors <2 cm, peripheral tumors, and with two positive nodes or less, the incidence of nipple involvement was 6.7%. When the nipple and areolar involvement were analyzed separately, only 2 of 217 patients had involvement of the areola (0.9%). All patients with areolar involvement had stage 3 breast cancer and were located centrally in the breast. We conclude from these data that nipple preservation is not a reasonable option for mastectomy patients. However, preservation of the areola with mastectomy in selected patients warrants further study.BackgroundSkin-sparing mastectomy (SSM), which involves the resection of the nipple/areolar complex with the breast parenchyma, improves the aesthetic outcome for breast cancer patients. Most patients undergoing SSM desire reconstruction of the nipple/areolar complex for symmetry. These data explore the possibility of preserving the areola in selected mastectomy patients.MethodsA retrospective analysis of 217 mastectomy patients was conducted to determine the frequency of malignant nipple and/or areola involvement. The association between nipple and/or areola involvement and prognostic factors, including tumor size, stage, nuclear grade, axillary nodal status, and tumor location, was evaluated.ResultsThe overall frequency of malignant nipple involvement was 23 of 217 (10.6%). In a subgroup of patients with tumors <2 cm, peripheral tumors, and with two positive nodes or less, the incidence of nipple involvement was 6.7%. When the nipple and areolar involvement were analyzed separately, only 2 of 217 patients had involvement of the areola (0.9%). All patients with areolar involvement had stage 3 breast cancer and were located centrally in the breast.ConclusionsWe conclude from these data that nipple preservation is not a reasonable option for mastectomy patients. However, preservation of the areola with mastectomy in selected patients warrants further study.


Cancer | 2000

Patterns of detection in patients with cutaneous melanoma

Mary S. Brady; Susan A. Oliveria; Paul J. Christos; Marianne Berwick; Daniel G. Coit; Jared Katz; Allan C. Halpern

Despite the importance of early detection in preventing mortality from melanoma, little is known regarding how patients with the disease come to diagnosis.


Clinical Cancer Research | 2013

Phase II Study of Lutetium-177–Labeled Anti-Prostate-Specific Membrane Antigen Monoclonal Antibody J591 for Metastatic Castration-Resistant Prostate Cancer

Scott T. Tagawa; Matthew I. Milowsky; Michael J. Morris; Shankar Vallabhajosula; Paul J. Christos; Naveed Akhtar; Joseph R. Osborne; Stanley J. Goldsmith; Steve Larson; Neeta Pandit Taskar; Howard I. Scher; Neil H. Bander; David M. Nanus

Purpose: To assess the efficacy of a single infusion of radiolabeled anti-prostate-specific membrane antigen (PSMA) monoclonal antibody J591 (lutetium-177; 177Lu) by prostate-specific antigen (PSA) decline, measurable disease response, and survival. Experimental Design: In this dual-center phase II study, two cohorts with progressive metastatic castration-resistant prostate cancer received one dose of 177Lu-J591 (15 patients at 65 mCi/m2, 17 at 70 mCi/m2) with radionuclide imaging. Expansion cohort (n = 15) received 70 mCi/m2 to verify response rate and examine biomarkers. Results: Forty-seven patients who progressed after hormonal therapies (55.3% also received prior chemotherapy) received 177Lu-J591. A total of 10.6% experienced ≥50% decline in PSA, 36.2% experienced ≥30% decline, and 59.6% experienced any PSA decline following their single treatment. One of 12 with measurable disease experienced a partial radiographic response (8 with stable disease). Sites of prostate cancer metastases were targeted in 44 of 47 (93.6%) as determined by planar imaging. All experienced reversible hematologic toxicity, with grade 4 thrombocytopenia occurring in 46.8% (29.8% received platelet transfusions) without significant hemorrhage. A total of 25.5% experienced grade 4 neutropenia, with one episode of febrile neutropenia. The phase I maximum tolerated dose (70 mCi/m2) resulted in more 30% PSA declines (46.9% vs. 13.3%, P = 0.048) and longer survival (21.8 vs. 11.9 months, P = 0.03), but also more grade 4 hematologic toxicity and platelet transfusions. No serious nonhematologic toxicity occurred. Those with poor PSMA imaging were less likely to respond. Conclusion: A single dose of 177Lu-J591 was well tolerated with reversible myelosuppression. Accurate tumor targeting and PSA responses were seen with evidence of dose response. Imaging biomarkers seem promising. Clin Cancer Res; 19(18); 5182–91. ©2013 AACR.


Cancer | 2006

FDG‐PET after 1 cycle of therapy predicts outcome in diffuse large cell lymphoma and classic Hodgkin disease

Lale Kostakoglu; Stanley J. Goldsmith; John P. Leonard; Paul J. Christos; Richard R. Furman; Tamer Atasever; Angely Chandramouly; Sumeet Verma; Pratichi Kothari; Morton Coleman

Early prediction of response to therapy may offer the potential to identify patients who will benefit from standard conventional therapy. The objective of this study was to determine the predictive value of FDG‐PET as an early response indicator after 1 cycle of chemotherapy for progression‐free survival (PFS) in diffuse large cell lymphoma (DLCL) and classic Hodgkin disease (HD).


Journal of The American College of Surgeons | 2000

Predictive factors associated with axillary lymph node metastases in T1a and T1b breast carcinomas: analysis in more than 900 patients.

David E. Rivadeneira; Rache M. Simmons; Paul J. Christos; Kayane Hanna; John M. Daly; Michael P. Osborne

BACKGROUND Axillary lymph node metastasis (ALNM) represents the single most important prognostic indicator in patients diagnosed with breast cancer. The proportion of < or = 1-cm (T1a, T1b) invasive breast carcinomas is increasing. The incidence and predictive factors associated with ALNM in patients with < or = 1-cm tumors remains unclear and the role of axillary lymph node dissection in these patients has been questioned. The purpose of this study was to determine clinical and pathologic factors predictive of ALNM in patients with < or = 1-cm invasive breast carcinomas by univariate and multivariate analyses. STUDY DESIGN Review analysis from a prospective database identified patients with < or = 1-cm invasive breast cancers treated at our institution between 1990 and 1996. All patients underwent a resection of the primary tumor and axillary lymph node dissections. Routine patient and tumor characteristics evaluated included: age, race, tumor size, histologic grade, estrogen and progesterone receptor status, and lymphatic and vascular invasion. Univariate and multivariate analyses were performed. Adjusted odds ratios (OR) and 95% confidence intervals (CI) are presented. RESULTS A total of 919 patients were identified in this study with tumors < or = 1 cm. These included 199 patients (21.7%) with T1a tumors and 720 patients (78.3%) with T1b tumors. ALNM was detected in 165 patients with an overall incidence of 18.0%. Of the ALNM group, 32 patients (19.4%) had T1a tumors and 133 patients (80.6%) had T1b tumors. Four variables were found to be significant in univariate analysis. These included: increasing tumor size, poor histologic grade, presence of lymphatic or vascular invasion, and younger age of the patient. An increase in tumor size was associated with a significant risk of ALNM (OR = 2.66, 95% CI = 1.28 to 5.75; p = 0.01). Poor tumor grade and the presence of lymphatic or vascular invasion were also associated with an increased risk of ALNM (OR = 2.69, p = 0.003 and OR = 5.52, p = 0.0001, respectively). Patients with ALNM were more likely to have a tumor grade of 3 (25.0% ALNM versus 12.5% node-negative, p = 0.004) and lymphatic or vascular invasion (16.9% ALNM versus 3.5% node-negative, p < 0.0001). In multivariate analysis, an increased risk of ALNM was demonstrated with increasing tumor size (0.1-cm increments), poor histologic grade, and younger age. CONCLUSIONS This study investigated clinical and pathologic factors influencing ALNM in patients with T1a and T1b breast carcinomas. We have identified three factors by multivariate analysis as significant independent predictors of ALNM in this group of patients. These include increasing tumor size, poor histologic grade, and younger age. Given the significant amount of ALNM demonstrated in this study (overall 18%) and the inability to identify a subgroup of patients that had an acceptable low risk of ALNM, the complete omission of assessing the axilla for metastatic disease in patients with small breast cancers cannot be advocated. Our recommendation for patients diagnosed with T1a and T1b tumors is to have their axilla investigated for metastatic disease either by traditional axillary lymph node dissections or by intraoperative lymphatic mapping and sentinel lymph node biopsy techniques.


Journal of The European Academy of Dermatology and Venereology | 2006

Profile of 513 patients with alopecia areata: associations of disease subtypes with atopy, autoimmune disease and positive family history

C Goh; M Finkel; Paul J. Christos; Animesh A. Sinha

Background  Several lines of evidence support a genetic component to alopecia areata (AA), including differences in patients based on severity of AA, associated diseases and family history.

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