Xeroderma pigmentosum complementation group C single-nucleotide polymorphisms in the nucleotide excision repair pathway correlate with prolonged progression-free survival in advanced ovarian cancer.

BACKGROUND: The nucleotide excision repair (NER) pathway is the principal DNA repair pathway for removing bulky platinum DNA adducts. Suboptimal DNA repair may lead to improved response to platinum agents. The objective of this study was to determine whether single-nucleotide polymorphisms (SNPs) in NER pathway genes could be markers of platinum response in ovarian cancer. METHODS: The authors identified patients with advanced-stage, papillary serous ovarian cancer who underwent primary cytoreductive surgery followed by platinum-based chemotherapy. DNA was isolated from peripheral blood specimens. Twenty-two SNPs within NER genes (xeroderma pigmentosum [XP] complementation group A [XPA], XPB/excision repair cross-complementing rodent repair deficiency, complementation group 3 [ERCC3], XPC, XPD/ERCC2, XPF/ERCC4, XPG/ERCC5, Cockayne syndrome group B protein [CSB]/ERCC8, ERCC1) were genotyped using polymerase chain reaction analysis. RESULTS: In total, 139 patients with stage III and IV papillary serous ovarian cancer were genotyped. The XPC (reference SNP 3731108 [rs3731108]) adenosine-guanine (AG)/AA genotype versus the GG genotype was associated with prolonged a progression-free survival (PFS) of 21.3 months versus 13.4 months (hazard ratio [HR], 0.63; 95% confidence interval [CI], 0.42-0.95; P = .03). The XPC (rs1124303) guanosine-thymidine (GT)/GG genotype versus the TT genotype was associated with a prolonged PFS of 22.8 months versus 14.9 months (HR, 0.47; 95% CI, 0.24-0.94; P = .03). The XPC poly(AT) (PAT) (-/+)/(-/-) genotype versus the (+/+) genotype was associated with a prolonged PFS of 17 months versus 11.6 months (HR, 0.56; 95% CI, 0.36-0.89; P = .01). The XPF/ERCC4 (rs12926685) cytidine-thymidine (CT)/CC genotype versus the TT genotype was associated with a prolonged PFS of 16.7 months versus 12.4 months (HR, 0.63; 95% CI, 0.41-0.95; P = .03). On multivariate analysis adjusting for breast cancer (BRCA) gene and cytoreductive surgery status, the XPC SNPs remained significantly associated with prolonged PFS. CONCLUSIONS: The current results indicated that XPC is a key component of the NER pathway that participates in DNA damage repair. SNPs in the XPC gene may represent novel markers of ovarian cancer response to platinum-based chemotherapy.

Hidden abnormalities and novel classification of t(15;17) acute promyelocytic leukemia (APL) based on genomic alterations.

Acute promyelocytic leukemia (APL) is a hematopoietic malignant disease characterized by the chromosomal translocation t(15;17), resulting in the formation of the PML-RARA gene. Here, 47 t(15;17) APL samples were analyzed with high-density single-nucleotide polymorphism microarray (50-K and 250-K SNP-chips) using the new algorithm AsCNAR (allele-specific copy-number analysis using anonymous references). Copy-number-neutral loss of heterozygosity (CNN-LOH) was identified at chromosomes 10q (3 cases), 11p (3 cases), and 19q (1 case). Twenty-eight samples (60%) did not have an obvious alteration (normal-copy-number [NC] group). Nineteen samples (40%) showed either one or more genomic abnormalities: 8 samples (17%) had trisomy 8 either with or without an additional duplication, deletion, or CNN-LOH (+8 group); and 11 samples (23%) had genomic abnormalities without trisomy 8 (other abnormalities group). These chromosomal abnormalities were acquired somatic mutations. Interestingly, FLT3-ITD mutations (11/47 cases) occurred only in the group with no genomic alteration (NC group). Taken together, these results suggest that the pathway of development of APL differs in each group: FLT3-ITD, trisomy 8, and other genomic changes. Here, we showed for the first time hidden abnormalities and novel disease-related genomic changes in t(15;17) APL.

Cloning of genes involved in chromosomal translocations by high-resolution single nucleotide polymorphism genomic microarray.

High-resolution single nucleotide polymorphism genomic microarray (SNP-chip) is a useful tool to define gene dosage levels over the whole genome, allowing precise detection of deletions and duplications/amplifications of chromosomes in cancer cells. We found that this new technology can also identify breakpoints of chromosomes involved in unbalanced translocations, leading to identification of fusion genes. Using this technique, we found that the PAX5 gene was rearranged to a variety of partner genes including ETV6, FOXP1, AUTS2, and C20orf112 in pediatric acute lymphoblastic leukemia (ALL). The 3' end of the PAX5 gene was replaced by the partner gene. The PAX5 fusion products bound to PAX5 recognition sequences as strongly as wild-type PAX5 and suppressed its transcriptional activity in a dominant-negative fashion. In human B cell leukemia cells, binding of wild-type PAX5 to a regulatory region of BLK, one of the direct downstream target genes of PAX5, was diminished by expression of the PAX5-fusion protein, leading to repression of BLK. Expression of PAX5-fusion genes in murine bone marrow cells blocked development of mature B cells. PAX5-fusion proteins may contribute to leukemogenesis by blocking differentiation of hematopoietic cells into mature B cells. SNP-chip is a powerful tool to identify fusion genes in human cancers.

Chromosomal abnormalities and novel disease-related regions in progression from Barrett's esophagus to esophageal adenocarcinoma.

Barrett's esophagus (BE) is a metaplastic condition caused by chronic gastroesophageal reflux which represents an early step in the development of esophageal adenocarcinoma (EAC). Single-nucleotide polymorphism microarray (SNP-chip) analysis is a novel, precise, high-throughput approach to examine genomic alterations in neoplasia. Using 250K SNP-chips, we examined the neoplastic progression of BE to EAC, studying 11 matched sample sets: 6 sets of normal esophagus (NE), BE and EAC, 4 of NE and BE and 1 of NE and EAC. Six (60%) of 10 total BE samples and 4 (57%) of 7 total EAC samples exhibited 1 or more genomic abnormalities comprising deletions, duplications, amplifications and copy-number-neutral loss of heterozygosity (CNN-LOH). Several shared abnormalities were identified, including chromosome 9p CNN-LOH [2 BE samples (20%)], deletion of CDKN2A [4 BE samples (40%)] and amplification of 17q12-21.2 involving the ERBB2, RARA and TOP2A genes [3.1 Mb, 2 EAC (29%)]. Interestingly, 1 BE sample contained a homozygous deletion spanning 9p22.3-p22.2 (1.2 Mb): this region harbors only 1 known gene, basonuclin 2 (BNC2). Real-time PCR analysis confirmed the deletion of this gene and decreased the expression of BNC2 mRNA in the BE sample. Furthermore, transfection and stable expression of BNC2 caused growth arrest of OE33 EAC cells, suggesting that BNC2 functions as a tumor suppressor gene in the esophagus and that deletion of this gene occurs during the development of EAC. Thus, this SNP-chip analysis has identified several early cytogenetic events and novel candidate cancer-related genes that are potentially involved in the evolution of BE to EAC.

Frequent genomic abnormalities in acute myeloid leukemia/myelodysplastic syndrome with normal karyotype.

BACKGROUND: Acute myeloid leukemia is a clonal hematopoietic malignant disease; about 45-50% of cases do not have detectable chromosomal abnormalities. Here, we identified hidden genomic alterations and novel disease-related regions in normal karyotype acute myeloid leukemia/myelodysplastic syndrome samples. DESIGN AND METHODS: Thirty-eight normal karyotype acute myeloid leukemia/myelodysplastic syndrome samples were analyzed with high-density single-nucleotide polymorphism microarray using a new algorithm: allele-specific copy-number analysis using anonymous references (AsCNAR). Expression of mRNA in these samples was determined by mRNA microarray analysis. RESULTS: Eighteen samples (49%) showed either one or more genomic abnormalities including duplication, deletion and copy-number neutral loss of heterozygosity. Importantly, 12 patients (32%) had copy-number neutral loss of heterozygosity, causing duplication of either mutant FLT3 (2 cases), JAK2 (1 case) or AML1/RUNX1 (1 case); and each had loss of the normal allele. Nine patients (24%) had small copy-number changes (< 10 Mb) including deletions of NF1, ETV6/TEL, CDKN2A and CDKN2B. Interestingly, mRNA microarray analysis showed a relationship between chromosomal changes and mRNA expression levels: loss or gain of chromosomes led, respectively, to either a decrease or increase of mRNA expression of genes in the region. CONCLUSIONS: This study suggests that at least one half of cases of normal karyotype acute myeloid leukemia/myelodysplastic syndrome have readily identifiable genomic abnormalities, as found by our analysis; the high frequency of copy-number neutral loss of heterozygosity is especially notable.

Genome-wide loss of heterozygosity and uniparental disomy in BRCA1/2-associated ovarian carcinomas.

PURPOSE: The importance of the BRCA gene products in maintaining genomic stability led us to hypothesize that BRCA-associated and sporadic ovarian cancers would have distinctive genetic profiles despite similarities in histologic appearance. EXPERIMENTAL DESIGN: A whole-genome copy number analysis of fresh, frozen, papillary serous ovarian cancer DNA was done using the Affymetrix 50K Xba Mapping Array using each patient's normal genomic DNA as the matched control. Loss of heterozygosity and copy number abnormalities were summarized to define regions of amplification, deletion, or uniparental disomy (UPD), defined as loss of one allele and duplication of the remaining allele. Genomic abnormalities were compared between BRCA-associated and sporadic tumors. RESULTS: We compared 6 BRCA-associated with 14 sporadic papillary serous ovarian carcinomas. Genetic instability, measured by percentage of genome altered, was more pronounced in BRCA-associated tumors (median, 86.6%; range, 54-100%) than sporadic tumors (median, 43.6%; range, 2-83%; P = 0.009). We used frequency plots to show the proportion of cases affected by each type abnormality at each genomic region. BRCA-associated tumors showed genome-wide loss of heterozygosity primarily due to the occurrence of UPD rather than deletion. UPD was found in 100% of the BRCA-associated and 50% of the sporadic tumors profiled. CONCLUSIONS: This study reports on a previously underappreciated genetic phenomenon of UPD, which occurs frequently in ovarian cancer DNA. We observed distinct genetic patterns between BRCA-associated and sporadic ovarian cancers, suggesting that these papillary serous tumors arise from different molecular pathways.

Genetic profiling of myeloproliferative disorders by single-nucleotide polymorphism oligonucleotide microarray.

OBJECTIVE: Myeloproliferative disorders (MPD) are clonal hematopoietic diseases that include polycythemia vera (PV), essential thrombocytosis (ET), and primary myelofibrosis (PMF). Mutations in JAK2 are present in many MPD patients. Additional genomic abnormalities are not fully examined in MPD. MATERIALS AND METHODS: We used single-nucleotide polymorphism DNA microarray (SNP-chip) to analyze 43 patients with MPD (10 PV, 17 ET, and 16 PMF) for genomic aberrations. RESULTS: Genomic abnormalities were rare in ET. The region containing either RB (13q14) or NF1 (17q11) was deleted in 4 of the 16 PMF, especially PMF with no JAK2 mutations. All five cases of PV having homozygous JAK2V617F had loss of heterozygosity with normal copy number [uniparental disomy] involving the gene. A subpopulation with 9p uniparental disomy was detected in 11 MPD (3 PV, 1 ET, 7 PMF). Uniparental disomy at 1p was found in one PV and three PMF. A novel mutation of MPL (Y591D), which was involved in this uniparental disomy, was found in 1 PV with JAK2 mutation. The other three cases of PMF with 1p uniparental disomy had point mutations of the MPL gene, either a novel mutation (S204F) or the previously described W515L. CONCLUSION: Genomic abnormalities, including 9p uniparental disomy/JAK2 point mutations, 1p uniparental disomy/MPL point mutations, deletions of RB1 and NF1 are common alterations in MPD, especially in PMF.

FBXW7 mutation in adult T-cell and B-cell acute lymphocytic leukemias.

The FBXW7 (also known as AGO, hCDC4, FBW7 and SEL-10) gene encodes a subunit of an ubiquitin protein ligase which regulates levels of cyclin E, NOTCH and other proteins. Engineered FBXW7 null cells display cell cycle and chromosome stability defects. Mutations of FBXW7 have been found in human colorectal, ovarian, endometrial tumors and T-cell acute lymphocytic leukemias. Prompted by these findings we have examined acute myeloid leukemia, non-Hodgkin's lymphoma, T-cell acute lymphocytic leukemia, B-cell acute lymphocytic leukemia and adult T-cell leukemia DNA for mutations of the FBXW7 gene. Mutations were detected by PCR-SSCP of all coding exons of the three isoforms of FBXW7, shifted bands were direct sequenced. As expected, mutations were found in T-cell acute lymphocytic leukemias. However mutations of FBXW7 were also found in four of 118 B-cell acute lymphocytic leukemias and one of 24 adult T-cell leukemia samples. The nucleotide changes consisted of an insertion, resulting in a frameshift mutation, and missense mutations of highly conserved residues. All mutations affected the FBXW7 target interacting domain. These observations suggest that disruption of FBXW7 has a role in several forms of lymphocytic leukemias and not exclusively T-cell acute lymphocytic leukemia.

Functional domains of CCN1 (Cyr61) regulate breast cancer progression.

CCN1 plays diverse roles in cellular proliferation, survival, migration and angiogenesis. We determined the relationship between CCN1 protein expression and clinical factors that are important for the classification of breast cancer. CCN1 contains four functional domains; the contribution of each of the structural domains to the biological properties of CCN1 in breast cancer was investigated. We performed immunohistochemistry for CCN1 on a breast cancer tissue array, and conducted a detailed statistical analysis on the relationship between CCN1 protein expression and clinical factors that are important for the classification of breast cancer. The structure-function relationship was examined using four mutant constructs in which one of the modules (DM1-DM4) had been deleted. MCF-7 breast cancer cells were stably transfected with these constructs and their biological activity was tested in comparison to full-length CCN1. Staining of CCN1 in tumors was positively correlated with AJCC disease stage. A strong association also was found between lymph node involvement and high CCN1 expression in patients with invasive breast cancer; there was a significant increase in the breast cancer expression of CCN1 in patients with positive lymph nodes (P=0.004), and the levels of CCN1 correlated with the number of positive lymph nodes (P=0.0006). Deletion of module 4 rendered CCN1 unable to either bind heparin or associate with the extracellular matrix. Furthermore, MCF-7/DM4 cells demonstrated reduced cell spreading, migration and proliferation, indicating that module 4 of the protein is important for its ability to promote these activities. These findings indicate that CCN1 is involved throughout the clinical progression of breast cancer to an invasive phenotype. The multimodular structure of CCN1 enables it to fulfill multiple functions that may contribute to the different stages of cancer development, raising the prospect that specific regions of CCN1 could be targeted for therapeutic benefit to inhibit particular aspects of malignancy in breast cancer.

Epigenetic silencing of the candidate tumor suppressor gene Per1 in non-small cell lung cancer.

PURPOSE: Epigenetic events are a critical factor contributing to cancer development. The purpose of this study was to identify tumor suppressor genes silenced by DNA methylation and histone deacetylation in non-small cell lung cancer (NSCLC). EXPERIMENTAL DESIGN: We used microarray analysis to screen for tumor suppressor genes. RESULTS: We identified Per1, a core circadian gene, as a candidate tumor suppressor in lung cancer. Although Per1 levels were high in normal lung, its expression was low in a large panel of NSCLC patient samples and cell lines. Forced expression of Per1 in NSCLC cell lines led to significant growth reduction and loss of clonogenic survival. Recent studies showed that epigenetic regulation, particularly histone H3 acetylation, is essential for circadian function. Using bisulfite sequencing and chromatin immunoprecipitation, we found that DNA hypermethylation and histone H3 acetylation are potential mechanisms for silencing Per1 expression NSCLC. CONCLUSIONS: These results support the hypothesis that disruption of circadian rhythms plays an important role in lung tumorigenesis. Moreover, our findings suggest a novel link between circadian epigenetic regulation and cancer development.

Health status, physical disability, and obesity among adult Mississippians with chronic joint symptoms or doctor-diagnosed arthritis: findings from the Behavioral Risk Factor Surveillance System, 2003.

INTRODUCTION: The purpose of this study was to analyze 2003 Mississippi Behavioral Risk Factor Surveillance System (BRFSS) data to describe the health of Mississippians with arthritis or chronic joint pain. For this study, we made statistical estimates of the extent of arthritis burden among the respondents and delineated measurable differences in sociodemographic factors, health status, and the prevalence of associated risk factors. Our findings compare health-related quality of life, physical activity, and key demographic characteristics and obesity rates, controlling for differences among the subgroups by age, sex, educational attainment, income, and race/ethnicity. METHODS: Respondents to Mississippi's 2003 BRFSS were assigned to 1 of 5 distinct and mutually exclusive subgroups: 1) those with intermittent joint symptoms (IJS), 2) those with chronic joint symptoms (CJS), 3) those with doctor-diagnosed arthritis without CJS (DDA-CJS), 4) those with doctor-diagnosed arthritis with chronic joint symptoms (DDA+CJS), and 5) those with no joint symptoms (NJS). To determine the prevalence of arthritis and the continuum of disease progression, we compared the health-related quality of life, physical activity, and obesity of the respondents. RESULTS: Respondents with DDA+CJS were older than those with NJS (mean age, 57.1 years vs 38.7 years); they were more likely to be female (60.5% vs 51.7%), to have a high school diploma or less education (59.3% vs 45.4%), to be in fair to poor health (odds ratio [OR], 10.0), to be physically inactive (OR, 2.7), and to be overweight or obese (OR, 2.5). CONCLUSION: Health status, physical disability, and weight control may be substantially improved through heightened levels of physical activity. However, in spite of the potential for marked improvement, adult Mississippians, especially those clients with DDA+CJS, remain reluctant to commit to exercise regimens. Findings from this study suggest a need to encourage Mississippians with DDA+CJS to engage in some regular physical activity, which could reduce the damaging effects of disease and improve their health. Increasing the health care resources earmarked for arthritis self-help and physical activity programs is one potential avenue to address the problem.

Sociodemographic and health-related determinants of breast and cervical cancer screening behavior, 2005.

OBJECTIVES: To identify sociodemographic and health-related determinants of Breast and Cervical Cancer Screening behaviors and evaluate progress toward Healthy People 2010 cancer-related objectives. DESIGN: The Behavioral Risk Factor Surveillance System 2005 data served as the numerical predicate for identifying or validating sociodemographic and health-related quality of life predictors, or both, and for determining any relative progress. SETTING/PARTICIPANTS: Eleven U.S. states (n = 27,625 women). MAIN OUTCOME MEASURES: Determinants of Breast and Cervical Cancer Screening and assessment of progress toward Healthy People 2010 objectives 3-11 and 3-13. RESULTS: Nine significant predictors of annual Breast and Cervical Cancer Screening (reported as odds ratios) were identified through regression analysis: adequate health care coverage, nonsmoking, age between 40 and 64 years, age greater than or equal to 65 years, no activity limitations, Black, non-Hispanic race, income greater than or equal to $35K, current exercise performance, and no risk for high blood cholesterol. Also, Healthy People 2010 objective 3-11 was not met; however, objective 3-13 was exceeded by 2.0%. CONCLUSIONS: The national health initiatives appear to benefit select American women (overall declining mortality rates from breast and cervical cancer); however, there seems to be a negative economy of scale with respect to age-as age increases, Breast and Cervical Cancer Screening declines and morbidity/mortality increases. Given this disparity, as of 2005, related Healthy People 2010 objectives remain unrealized.

Rare mutations of the PIK3CA gene in malignancies of the hematopoietic system as well as endometrium, ovary, prostate and osteosarcomas, and discovery of a PIK3CA pseudogene.

Lipid kinase PIK3CA mutations have been described in several cancers. They clustered in two 'hot spots' located in helical (exon 9) and kinase (exon 20) domains associated with increased kinase activity strongly suggesting oncogenic potential. Mutational analysis of previously unexamined tumors showed an amino acid change from threonine to alanine (T1025A) in exon 20 in one of 28 endometrial cancer samples and 6 endometrial cell lines. Additionally, a silent polymorphism (T1025T) was found in two of 20 MDS samples, one of 43 NHL samples, two of 40 osteosarcoma samples and Ishikawa. The polymorphism was established by identifying two of 92 normal samples with the same change. No PIK3CA mutations were found in acute myeloid leukemia (AML), myelodysplastic syndromes (MDS) and non-Hodgkin lymphomas (NHL) as well as in osteosarcomas, prostate and ovarian cancer samples. Additionally, a previously unidentified PIK3CA pseudogene spanning exons 9-13 on chromosome 22 was discovered.

KLF6: mutational analysis and effect on cancer cell proliferation.

Kruppel-like factor 6 (KLF6/Zf9/CPBP), a member of the Kruppel-like family of zinc finger transcription factors, has recently been suggested to be a mutated tumor suppressor in selected human cancers. Initially, we investigated whether the KLF6 gene was altered in 36 paired non-small cell lung cancers (NSCLC), 89 brain tumors, 7 normal brains, 46 cancer cell lines from a large variety of tissues, and 144 peripheral blood cells from healthy individuals using single strand conformation polymorphism (PCR-SSCP) and DNA sequencing. Changes in the coding region of KLF6 were found in brain tumors (missense changes, 8%; silent polymorphisms, 2%), lung cancers (missense changes, 3%; silent polymorphisms, 6%) and cancer cell lines (missense changes, 2%; silent polymorphisms, 2%). All of the nucleotide changes in the lung tumor samples were present in their matched normal samples, suggesting that these changes were germline polymorphism. Many of the altered KLF6 genes found in the brain tumors were cloned into an expression vector and placed into a GBM cell line, and cell growth was monitored. Wild-type, deleted exon 3, or E30G missense KLF6 significantly reduced cell growth; in contrast, forced expression of KLF6 having either the S92R, P183L or A276G missense substitution did not alter the growth of transfected GBM cells (p > 0.05). Expression levels of KLF6 were higher in normal brain samples than in glioma samples as measured by real-time RT-PCR (p < 0.05). To our surprise, nucleotide changes were found at -4, -5, and -6 upstream of the start of translation in 45% of brain tumors, and 10% of normal blood samples. Focusing on the most frequent alteration (-4 C > A), the nucleotide change did not affect translation of KLF6. Taking together, KLF6 coding sequences are altered in 10% brain tumors, 8% NSLC, and 4% of cancer cell lines. All of those observed in lung cancer are germline polymorphisms. Several additional ones identified in GBM, have lost their ability to slow the growth of glioma cells; furthermore, a proportion of GBM have decreased expression of KLF6 as compared to normal brain tissue. Dysfunction of this gene may contribute to oncogenesis in the brain.

CYR61: a new measure of lung cancer outcome.

Cysteine-rich protein 61 (Cyr61) is a member of a family of growth factor-inducible, immediate-early genes. In this report, the authors measured the expression of Cyr61 mRNA in 94 human lung tumors and their normal matched lung samples. The Cyr61 mRNA levels were quantified by real time reverse transcriptase-polymerase chain reaction and calculated as a tumor/normal Cyr61 mRNA ratio in each case. Compared with normal matched lung tissues, expression of Cyr61 was decreased in 74 of 94 (79 percent) lung tumors. Differences in distribution of patient characteristics, such as gender, age, tumor size, and pathological diagnosis, between high or low Cyr61 expressing groups were not statistically significant. However, differences in distribution of clinical stage between high or low Cyr61 expressing groups was statistically significant; that is, the Cyr61 low expressor group was clinically more advanced than the Cyr61 high expressor group (p = 0.046). Furthermore, Cyr61 levels of the patients with N0 and N1 diseases were significantly higher than the expression in the N2 patients (p = 0.047). The 3-year survival between the Cyr61 very low tumor expressor group compared to matched normal lung (39 patients) and the higher Cyr61 expressor group (52 patients) was statistically significant (59 versus 91 percent; p = 0.05). Taken together, Cyr61 appears to guard against metastatic disease because low expression is associated with more advanced disease; and therefore, expression levels of Cyr61 correlate with the prognosis of lung cancer.

The impact of Hurricane Katrina upon older adult nurses: an assessment of quality of life and psychological distress in the aftermath.

The primary purpose of the current study was to evaluate the impact of Hurricane Katrina upon older nurses using cross sectional data from 291 respondents. Collected data served as the numerical predicate for the evaluation of quality of life and psychological distress among nurses who were affected by Hurricane Katrina. While the focus for the present study was upon older nurses, cross sectional data was reflected for the plenary sample as well. Predictors of Katrina's impact upon older nurses were identified through multinomial regression analyses and included the physical function subscale (OR=0.954), the fatigue subscale (OR=0.961), the arousal subscale (OR=4.190), average to poor health (OR=2.040), married (OR=2.769) and the MSPSS (OR = 0.780). Significant associations between age and storm impact (F=10.707, ñ=.001), depression (F=15.782, ñ< .001), social support (F=5.869, ñ=.016), health status (F=29.004, ñ<.001), anxiety (F=5.583, ñ=.019) and posttraumatic distress disorder (F .032, fñ= .46) remained after adjustment for other risk factors. These associations, as reflected in their respective mean scores, indicated that older nurses experienced greater storm impact (2.880 vs. 2.511), depressive symptoms (11.250 vs. 9.080), anxiety (77.800 vs. 75.430), posttraumatic distress (72.830 vs. 70.860) and lower health status (68.891 vs. 73.569). Accordingly, a more robust public policy paradigm for addressing the growing labor shortages in the medical community is needed. Heightened Congressional interest and increased resourcing is required in order to affect necessary programmatic, educational and institutional remediation. Furthermore, given the increasing role of older nurses in the work place, extensive studies are needed to evaluate their status and independent risk factors for sustaining quality of life and psychological well being among these contributors of health care.

SAHA, a HDAC inhibitor, has profound anti-growth activity against non-small cell lung cancer cells.

Current chemotherapy of advanced non-small cell lung cancer (NSCLC) produces only a modest increase in survival time. New approaches are needed for this disease. The development of lung cancer is associated with silencing tumor suppressor genes that can occur not only by deletion or mutation, but also by epigenetic changes including histone deacetylation of key lysines. Histone deacetylase inhibitor (HDACI) increases histone acetylation, resulting in DNA with a more open chromatin that favors transcription. We found that the HDACI, suberoylanilide hydroxamic acid (SAHA), suppressed cell growth of five non-small cell lung cancer cell lines in a dose-dependent manner (50% growth inhibition approximately 2 microM). Cell cycle assay by fluorescence-activated cell sorting (FACS) demonstrated that SAHA induced a significant G0-G1 growth arrest of NSCLC cells. Protein assay by Western blot analysis showed that SAHA induced expression of p21WAF1. These results demonstrated that administration of SAHA may be a novel approach to the treatment of non-small cell lung cancer.

Methylation, expression, and mutation analysis of the cell cycle control genes in human brain tumors.

Methylation status of the p15(INK4B), p16(INK4A), p14(ARF) and retinoblastoma (RB) genes was studied using methylation specific polymerase chain reaction (MSP) in 85 human brain tumors of various subtypes and four normal brain samples. These genes play an important role in the control of the cell cycle. Twenty-four out of 85 cases (28%) had at least one of these genes methylated. The frequency of p14(ARF) methylation was 15 out of 85 (18%) cases, and the expression of p14(ARF) in methylated gliomas was significantly lower than in unmethylated gliomas. The incidence of methylation of p15(INK4B), p16(INK4A) and RB gene was 4%, 7%, and 4%, respectively. Samples with p14(ARF) methylation did not have p16(INK4A) methylation even though both genes physically overlap. None of the target genes was methylated in the normal brain samples. In addition, the p53 gene was mutated in 19 out of 85 (22%) samples as determined by single strand conformation polymorphism (SSCP) analysis and DNA sequencing. Thirty out of 85 (35%) brain tumors had either a p53 mutation or methylation of p14(ARF). Also, the p14(ARF) expression in p53 wild-type gliomas was lower than levels in p53 mutated gliomas. This finding is consistent with wild-type p53 being able to autoregulate its levels by down-regulating expression of p14(ARF). In summary, inactivation of the apoptosis pathway that included the p14(ARF) and p53 genes by hypermethylation and mutation, respectively, occurred frequently in human brain tumors. Down-regulation of p14(ARF) in gliomas was associated with hypermethylation of its promoter and the presence of a wild-type p53 in these samples.

Cyr61 suppresses the growth of non-small-cell lung cancer cells via the beta-catenin-c-myc-p53 pathway.

Cysteine-rich protein 61 (Cyr61) is a growth factor-inducible, immediate-early gene that has multifaceted activities in various cancers. In a previous study, we found that Cyr61 inhibited the growth of the H520 and H460 non-small-cell lung cancer (NSCLC) cell lines. In further studies, we now report that p53 plays a pivotal role in Cyr61-dependent cellular growth arrest. Blocking Cyr61 with a Cyr61 antibody resulted in the downregulation of expression of p53 and p21, as well as partially reversing the growth suppression of H520-Cyr61 cells. Proliferation of NSCLC cell lines (NCI-H157, H125, H1299), having a mutant p53, were not suppressed by Cyr61. Inhibition of wild-type p53, by either human papilloma virus type 16 E6 or a dominant-negative p53, resulted in the rescue of the growth suppression mediated by Cyr61 in the H520-Cyr61 cells. The enhanced levels of p21WAF1 and p130/RB2, in the Cyr61-expressing H520-Cyr61 cells, were also inhibited by blocking p53 showing that p21 and p130 were induced by p53 in these cells. In addition, levels of both c-myc and beta-catenin increased in Cyr61 stably transfected H520 cells. Moreover, beta-catenin was translocated into the nucleus in these cells. Inhibition of c-myc expression in the H520-Cyr61 cells with antisense c-myc resulted in their decreased levels of p53. Transfecting cells with a dominant-negative T-cell factor (TCF4), the specific inhibitor of the beta-catenin/TCF4 complex, downregulated the expression of c-myc. Taken together, the data suggest that Cyr61 suppressed the growth of NSCLC cells by triggering a signal transduction pathway through beta-catenin. In this pathway, Cyr61 activated the beta-catenin/TCF4 complex, which promoted the expression of c-myc and the latter induced expression of p53, and p53 upregulated p21WAF1 and p130/RB2, resulting in growth arrest.

Allelic loss at 10q26 in osteosarcoma in the region of the BUB3 and FGFR2 genes.

Loss of heterozygosity at 10q26 was mapped using microsatellite markers in 20 osteosarcomas. A four-megabase region centered on marker D10S587 was affected by allelic loss in 60 percent of osteosarcomas. The most frequently lost marker was D10S1723. Around 15 known genes are found in this region. The gene immediately adjacent to D10S1723 encodes BUB3, an element of the spindle assembly mitotic checkpoint. Loss of BUB3 function could contribute to chromosomal instability. The fibroblast growth factor receptor 2 (FGFR2) gene is located 2 Mb from the BUB3 gene and has the potential for a role in cancer. Inherited mutations of the FGFR2 gene result in skeletal dysplasias. FGFR2 alterations have also been implicated in gastric cancer. Human genome project data were used to design primers for amplifying FGFR2 in 18 genomic segments and BUB3 in 7 genomic segments. In each case, the segments encompassed coding exons and flanking intron sequences. The primers were used to search for mutations by polymerase chain reaction-single-strand conformation polymorphism (PCR-SSCP). Several shifted bands were detected in the BUB3 exon 3 fragment. Sequencing resolved the BUB3 exon 3 fragment shifts into polymorphisms in intron 2. No mutations of BUB3 or FGFR2 were detected. It remains possible that BUB3 or FGFR2 hemizygosity alone contributes to osteosarcoma, or that one of the genes is cryptically inactivated by a higher-order modification or mutation outside the coding region. There may also be a yet undiscovered tumor suppressor gene in this region.