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Jennifer Hunt

Publications and source records attributed to Jennifer Hunt.

At least 19 recordsLinked to original sources
PubMed2007

Recurrent gynandroblastoma of ovary-A case report: a molecular and immunohistochemical analysis.

Gynandroblastoma is a rare ovarian tumor that is composed of both Sertoli cells and granulosa cells. Only 23 cases have been reported in the literature, and recurrence has never been described. We report the first case of a recurrent gynandroblastoma along with its molecular analysis and immunohistochemical studies. A 49-year-old Gravida 0 woman with a 10-year prior diagnosis of ovarian-mixed stromal tissue tumor (well-differentiated Sertoli cell and granulosa cell tumor) and staging laparotomy, presented now with a retroperitoneal mass and an elevated inhibin level. CT scan was suspicious for recurrence. The patient had no prior adjuvant therapy. The histomorphological features of the recurrent tumor had both Sertoli cell and granulosa cell tumor. The molecular analysis of both primary and recurrent tumor showed minor genetic instability in the 17q12.2 gene locus with no dedifferentiation or progression, which is consistent with a low-grade tumor. The immunohistochemical staining profile showed positivity for CD99, inhibin, calretinin, and vimentin; focal positivity for cytokeratin AE1/AE3 and negative for EMA and melan-A. All the previously mentioned immunostainings support the diagnosis. We report the first case of a recurrent gynandroblastoma 10 years after initial presentation along with its molecular analysis and immunohistochemical studies.

Adult↗
PubMed2006

Biological effects of anthropogenic contaminants in the San Francisco Estuary.

Concentrations of many anthropogenic contaminants in the San Francisco Estuary exist at levels that have been associated with biological effects elsewhere, so there is a potential for them to cause biological effects in the Estuary. The purpose of this paper is to summarize information about biological effects on the Estuary's plankton, benthos, fish, birds, and mammals, gathered since the early 1990s, focusing on key accomplishments. These studies have been conducted at all levels of biological organization (sub-cellular through communities), but have included only a small fraction of the organisms and contaminants of concern in the region. The studies summarized provide a body of evidence that some contaminants are causing biological impacts in some biological resources in the Estuary. However, no general patterns of effects were apparent in space and time, and no single contaminant was consistently related to effects among the biota considered. These conclusions reflect the difficulty in demonstrating biological effects due specifically to contamination because there is a wide range of sensitivity to contaminants among the Estuary's many organisms. Additionally, the spatial and temporal distribution of contamination in the Estuary is highly variable, and levels of contamination covary with other environmental factors, such as freshwater inflow or sediment-type. Federal and State regulatory agencies desire to develop biological criteria to protect the Estuary's biological resources. Future studies of biological effects in San Francisco Estuary should focus on the development of meaningful indicators of biological effects, and on key organism and contaminants of concern in long-term, multifaceted studies that include laboratory and field experiments to determine cause and effect to adequately inform management and regulatory decisions.

Animals↗
PubMed2006

Identification of a gene signature for rapid screening of oral squamous cell carcinoma.

PURPOSE: Oral cancer is a major health problem worldwide and in the U.S. The 5-year survival rate for oral cancer has not improved significantly over the past 20 years and remains at approximately 50%. Patients diagnosed at an early stage of the disease typically have an 80% chance for cure and functional outcome, however, most patients are identified when the cancer is advanced. Thus, a convenient and an accurate way to detect oral cancer early will decrease patient morbidity and mortality. The ability to noninvasively monitor oral cancer onset, progression, and treatment outcomes requires two prerequisites: identification of specific biomarkers for oral cancers as well as noninvasive access to and monitoring of these biomarkers that could be conducted at the point of care (i.e., practitioner's or dentist's office) by minimally trained personnel. EXPERIMENTAL DESIGN: Here, we show that DNA microarray gene expression profiling of matched tumor and normal specimens can identify distinct anatomic site expression patterns and a highly significant gene signature distinguishing normal from oral squamous cell carcinoma (OSCC) tissue. RESULTS: Using a supervised learning algorithm, we generated a 25-gene signature for OSCC that can classify normal and OSCC specimens. This 25-gene molecular predictor was 96% accurate on cross-validation, averaging 87% accuracy using three independent validation test sets and failing to predict non-oral tumors. CONCLUSION: Identification and validation of this tissue-specific 25-gene molecular predictor in this report is our first step towards developing a new, noninvasive, microfluidic-based diagnostic technology for mass screening, diagnosis, and treatment of pre-OSCC and OSCC.

Carcinoma, Squamous Cell↗
PubMed2006

Decreased STAT1 expression by promoter methylation in squamous cell carcinogenesis.

BACKGROUND: Dysregulation of signal transducers and activators of transcription (STATs) is associated with many cancers, but no role of STAT1 in human tumor progression has been demonstrated. METHODS: We compared STAT1 protein expression in squamous cell carcinoma of the head and neck (SCCHN) tumors (n = 28) and normal oropharyngeal mucosa samples (n = 10) from patients without cancer as assessed by immunoblotting. Stable clones were established from SCCHN 1483 cells that were transfected with a STAT1 expression construct; cell growth and cisplatin-induced apoptosis of the clones and vector control-transfected 1483 cells were compared using trypan blue exclusion and Annexin V staining and expression of the cyclin-dependent kinase inhibitor p21 was assayed by immunoblotting. The growth of STAT1-overexpressing SCCHN 1483 xenograft tumors was compared with that of xenograft tumors derived from cells transfected with vector control DNA. DNA from SCCHN tumors (n = 16) and paired peripheral blood lymphocytes were analyzed for STAT1 mutations and promoter methylation using methylation-specific polymerase chain reaction and bisulfite sequencing. SCCHN cell lines (PCI-15b, 1483, and UM-22B) were treated with the demethylating agent azacytidine alone or in combination with the cytotoxic drug cisplatin, and expression of STAT1 and p21 were monitored by immunoblotting. All statistical tests were two-sided. RESULTS: STAT1 levels were statistically significantly lower in the SCCHN tumors than normal mucosa (median = 0.8 relative units versus 2.4, difference = 1.6, 95% confidence interval [CI] = 1.3 to 2.0, P < .001). Overexpression of STAT1 abrogated the growth of SCCHN cells and xenograft tumors and increased p21 expression. STAT1 expression levels of the tumors with STAT1 promoter methylation (n = 12) were lower than those of tumors (n = 4) without promoter methylation of STAT1 (P = .008). Azacytidine treatment increased expression of STAT1 and p21 in SCCHN cell lines and increased apoptosis in cisplatin-treated 1483 cells compared with cisplatin treatment alone (mean = 61.3% versus 25.8%, difference = 35.5%, 95% CI = 24.5% to 43.4%; P = .028). CONCLUSION: STAT1 can function as a tumor suppressor in SCCHN cells. Silencing of the STAT1 gene via promoter methylation may contribute to SCCHN tumor cell growth.

Antineoplastic Agents↗
PubMed2006

Intraoperative assessment of ovarian tumors: a 5-year review with assessment of discrepant diagnostic cases.

Frozen section is often requested in the intraoperative assessment of patients, presenting with ovarian masses, to provide guidance for appropriate surgical management. To assess the accuracy of frozen section and identify causes of diagnostic error, we reviewed 914 consecutive ovarian frozen sections performed over a 5-year period in 2 laboratories; one of which provides a general surgical pathology service and, the other, a specialist gynecologic pathology service. Cases, in which there were significant diagnostic discrepancies between the intraoperative and the final histological diagnoses, were reviewed. The series included 552 benign lesions (60.4%), 96 borderline (atypical proliferating) epithelial tumors (10.5%), and 266 malignancies (29.1%). The overall accuracy of frozen section diagnosis was 95.3%. There were 43 cases with diagnostic discrepancy; 20 (3.8% cases) of which were reported in the specialist laboratory and 23 (5.9% cases) in the general laboratory. Underdiagnosis of tumor type accounted for 32 of 43 discrepant cases and was most frequent in borderline mucinous tumors. The most common cause of overdiagnosis was the misinterpretation of serous cystadenofibroma as borderline serous tumor. Slide review of the 41 assessable cases indicated that sampling error, pathologist misinterpretation, and suboptimal slide preparations contributed to misdiagnoses in 17, 23, and 9 tumors, respectively (in 9 cases, 2 factors were contributory), whereas no specific error was identified in the remaining case. Technical factors and pathologist misinterpretation were more common in the general pathology laboratory. This study confirms that ovarian frozen section is a generally reliable technique, but there are problematic areas, particularly involving the assessment of borderline tumors.

Cystadenoma, Mucinous↗
PubMed2005

Antitumor activity of human papillomavirus type 16 E7-specific T cells against virally infected squamous cell carcinoma of the head and neck.

Human papillomavirus (HPV)-associated squamous cell carcinoma of the head and neck (SCCHN) seems to be a suitable target for cancer vaccination. HPV-encoded oncogenic proteins, such as E7, are promising tumor-specific antigens and are obligatory for tumor growth. Because few immunologic studies have analyzed the endogenous HPV-specific immune response in this subset of SCCHN patients, we studied T-cell frequencies against HPV-16 E7(11-20) or E7(86-93) in tumor-bearing, human leukocyte antigen (HLA)-A*0201+ SCCHN patients, whose tumors were either HPV-16+ or HPV-16-. In HPV-16+ SCCHN patients, frequencies of T cells against either peptide were significantly elevated (P < 0.005) compared with HPV-16- patients or healthy volunteers. Tetramer+ T cells showed evidence of terminally differentiated phenotype (CD45RA+CCR7-) and an elevated level of CD107a staining for degranulation. Despite detectable expression of the restricting HLA class I allele, HLA-A*0201-E7(11-20)- or HLA-A*0201-E7(86-93)-specific CTL obtained by in vitro stimulation of healthy donor peripheral blood mononuclear cells only recognize a naturally HPV-16-transformed, HLA-A*0201+ SCCHN cell line after pretreatment with IFN-gamma. This cell line had little or no expression of LMP2, TAP1, and tapasin, critical components of the HLA class I antigen-processing machinery, which were up-regulated by IFN-gamma treatment. Immunohistochemistry of HPV-16+ SCCHN tumors showed that these antigen-processing machinery components are down-regulated in tumors in vivo compared with adjacent normal squamous epithelium. Thus, immunity to HPV-16 E7 is associated with the presence of HPV-16 infection and presentation of E7-derived peptides on SCCHN cells, which show evidence of immune escape. These findings support further development of E7-specific immunotherapy and strategies for up-regulation of antigen-processing machinery components in HPV-associated SCCHN.

Animals↗
PubMed2005

The relationship between UK hospital nurse staffing and emotional exhaustion and job dissatisfaction.

AIM: To explore the relationship between nurse outcomes (dissatisfaction and emotional exhaustion) and nurse workload, nurse characteristics and hospital variables. BACKGROUND: Concern about the impact of restructuring of nurse staffing, and reports of nurse shortages, on nurse and patient outcomes led to the research being reported on in this article. METHODS: A questionnaire survey of registered nurses in Scotland and England. A questionnaire survey of the hospitals in which these nurses worked. RESULTS: Respondents in the two countries were similar in terms of demographic, work and employment characteristics. Significant relationships were found using the combined English and Scottish data between nurse patient ratios and (1) emotional exhaustion and (2) dissatisfaction with current job reported by nurses. CONCLUSIONS: Increasing numbers of patients to nurses was associated with increasing risk of emotional exhaustion and dissatisfaction with current job.

Adult↗
PubMed2005

Understanding the genotype of follicular thyroid tumors.

Tumors of the thyroid with a follicular growth pattern are controversial and can be diagnostically challenging for the pathologist. This group of tumors includes both follicular derived lesions (adenomas and carcinomas) and papillary carcinoma (follicular variant of papillary carcinoma). H&E morphology has classically been the gold standard for diagnosis. In the past several decades, however, several important molecular markers have been identified that may be unique to different types of thyroid carcinomas. These include the translocations RET/PTC and PAX8-PPARgamma and point mutations in the BRAF and RAS genes. Other molecular events in tumor suppressor genes may be useful for diagnosis of these tumors as well. None of the mutational markers are very sensitive, and there is some question regarding specificity for malignancy, because mutations have also been described in histologically benign tumors. However, with increasing availability of molecular testing for the general pathologist, a molecular testing panel used in conjunction with the H&E morphology and immunohistochemical stains may become useful in the clinical setting for the diagnosis of thyroid tumors.

Carcinoma, Papillary, Follicular↗
PubMed2005

Performance of the revised Bethesda guidelines for identification of colorectal carcinomas with a high level of microsatellite instability.

CONTEXT: Criteria for microsatellite instability (MSI) testing to rule out hereditary nonpolyposis colorectal cancer were recently revised and include parameters such as age and specific histologic features that can be identified by the pathologist, triggering reflex MSI testing. OBJECTIVE: To review the performance of the revised Bethesda guidelines to identify MSI-positive colorectal cancers. DESIGN: Seventy-five patients with colorectal cancer were included; 68 patients younger than 50 years and 7 patients between 50 and 60 years were selected based on histopathologic criteria. Microsatellite instability testing with the National Cancer Institute--recommended panel and immunohistochemistry for hMLH1 and hMSH2 were performed. Tumors were classified into microsatellite instability high (MSI-H), low (MSI-L), or stable (MSS) categories. RESULTS: Overall, 17 (23%) of 75 colorectal cancer cases were classified as MSI-H, including 13 patients younger than 50 years and 4 patients between 50 and 60 years. Among the MSI-H tumors, 10 (59%) were characterized by loss of hMLH1 and 6 (35%) were hMSH2 negative. Histologic features suggestive of MSI-H phenotype were present in 80% of MSI-H and 35% of MSS/MSI-L tumors. The number of positive lymph nodes was higher in MSS/MSI-L adenocarcinomas (P = .04). CONCLUSIONS: By selecting for age and histologic features, we detected MSI-H tumors in approximately one quarter of colorectal cancer cases meeting the revised Bethesda guidelines and identified 17 MSI-H cases, whereas only 8 would have been recognized by the prior guidelines. These data indicate that reflex testing requested by pathologists based on the revised Bethesda guidelines increases the detection of MSI-H and potential hereditary nonpolyposis colorectal cancer cases.

Adaptor Proteins, Signal Transducing↗
PubMed2004

Allelic loss of tumor suppressor genes in ameloblastic tumors.

Ameloblastoma is an odontogenic tumor with a variety of histologic appearances and an unpredictable biologic behavior. Little is known about allelic losses of tumor suppressor genes in ameloblastomas. This study surveyed DNA damage in ameloblastomas and correlated this with histologic sub-type and clinical outcome. There were 12 ameloblastomas (two peripheral, eight solid, and two unicystic) and three ameloblastic carcinoma studied for loss of heterozygosity of tumor suppressor genes on chromosomes 1p, 3p, 9p,10q, and 17p (L-myc, hOGG1, p16, pten, and p53). The frequency of allelic loss and the intratumoral heterogeneity were calculated. L-myc (71% frequency of allelic loss) and pten (62% frequency of allelic loss) had the most frequent allelic losses. Overall frequency of allelic loss and intratumoral heterogeneity were higher in mandibular and in unicystic tumors and lower in tumors that recurred/metastasized. The rate of allelic loss in the three carcinomas was similar to that seen in benign tumors. The frequency of allelic loss and intratumoral heterogeneity did not correlate with age, gender, histologic subtype, or prognosis. Since tumors that behaved aggressively did not harbor more allelic losses, it is likely that DNA damage in ameloblastomas and ameloblastic carcinomas is sporadic and cumulative. We conclude that other genetic or epigenetic mechanisms may be responsible for malignant behavior in ameloblastic carcinomas.

Adult↗
PubMed2003

Galpha12 regulates epithelial cell junctions through Src tyrosine kinases.

Regulation and assembly of the epithelial cell junctional complex involve multiple signaling mechanisms, including heterotrimeric G proteins. Recently, we demonstrated that Galpha12 binds to the tight junction scaffolding protein ZO-1 through the SH3 domain and that activated Galpha12 increases paracellular permeability in Madin-Darby canine kidney (MDCK) cells (Meyer et al. J Biol Chem 277: 24855-24858, 2002). In the present studies, we explore the effects of Galpha12 expression on tight and adherens junction proteins and examine downstream signaling pathways. By confocal microscopy, we detect disrupted tight and adherens junction proteins with increased actin stress fibers in constitutively active Galpha12 (QLalpha12)-expressing MDCK cells. The normal distribution of ZO-1 and Na-K-ATPase was altered in QLalpha12-expressing MDCK cells, consistent with loss of polarity. We found that the tyrosine kinase inhibitor genistein and the Src-specific inhibitor PP-2 reversibly abrogated the QLalpha12 phenotype on the junctional complex. Junctional protein localization was preserved in PP-2- or genistein-treated QLalpha12-expressing cells, and the increase in paracellular permeability as measured by transepithelial resistance and [3H]mannitol flux was prevented by the inhibitors. Src activity was increased in QLalpha12-expressing MDCK cells as assessed by Src autophosphorylation, and beta-catenin tyrosine phosphorylation was also increased, although there was no detectable increase in Rho activity. Taken together, these results indicate that Galpha12 regulates MDCK cell junctions, in part through Src tyrosine kinase pathways.

Adherens Junctions↗
PubMed2003

Platelet factor 4 localization in carotid atherosclerotic plaques: correlation with clinical parameters.

Emerging evidence supports a role for platelets in the progression of atherosclerosis in addition to an involvement in thrombotic vascular occlusion. Platelet Factor 4 (PF4), a chemokine released by activated platelets, stimulates several pro-atherogenic processes. Therefore, we examined the localization of PF4 and the homologous protein, Neutrophil Activating Protein-2 (NAP-2) in lesions representing the evolution of human atherosclerotic plaques. Carotid plaques from 132 patients with critical carotid stenosis and 6 autopsy specimens were studied. Clinical, histologic and immunohistochemical data were analyzed using a chi(2)-test. PF4 was detected in the cytoplasm of luminal and neovascular endothelium, in macrophages and in regions of plaque calcification. The presence of PF4 in macrophages and neovascular endothelium correlated with lesion grade (p = 0.004; p = 0.044). Staining of macrophages for PF4 correlated with the presence of symptomatic atherosclerotic disease (p = 0.028). In early lesions, PF4 was commonly found in macrophages of early lesions (Grade I/II), whereas NAP-2 was rarely present. In conclusion, correlation between PF4 deposition, lesion severity and symptomatic atherosclerosis suggests that persistent platelet activation may contribute to the evolution of atherosclerotic vascular lesions. These studies support the rationale for the chronic use of anti-platelet therapy in patients at risk for developing symptomatic atherosclerosis.

Adult↗
PubMed2002

T cell receptor gamma-chain gene polymerase chain reaction to diagnose central nervous system involvement by cutaneous T cell lymphoma.

The authors describe a patient who was suspected of having cutaneous T cell lymphoma involvement of the brain despite repeatedly negative cerebrospinal fluid (CSF) cytology, inconclusive flow cytometry, and no discrete lesion for brain biopsy. The diagnosis was made by polymerase chain reaction (PCR) analysis that showed a monoclonal T cell receptor gamma-chain gene rearrangement in the CSF, identically sized to that present in a skin biopsy specimen. Thus, PCR could be used early and routinely to diagnose central nervous system spread of T cell lymphomas, because of its potentially superior sensitivity and specificity to CSF cytology.

Aged↗
PubMed2002

When (and what) is an egg?

The meaning of the term 'egg' is defined by the particular 'universe of discourse' in use. The discourse within an in vitro fertilization clinic will differ from the discourse in the domestic world of patients. Thus, it is imperative that any decision to donate or share eggs takes note of all possible universes, both present and future.

Female↗