On a Test of Whether one of Two Random Variables is Stochastically Larger than the Other

Mann, Henry B.; Whitney, Douglas R.

doi:10.1214/aoms/1177730491

Cited by 10,735 publications

(5,988 citation statements)

References 2 publications

Supporting

Mentioning

5,496

Contrasting

Unclassified

118

Order By: Relevance

“…Since most variables did not comply with normal Gaussian distribution as determined by the Kolmogorov-Smirnov test, 18,19 a nonparametric Mann-Whitney U-test 20 or Kruskal-Wallis test 21 was applied in order to compare independent samples of continuous variables. All p-values were based on 2-sided tests and the threshold to accept statistical significance was set at the alpha level 0.05.…”

Section: Discussionmentioning

confidence: 99%

CXCR4 expression reflects tumor progression and regulates motility of bladder cancer cells

Retz

Sidhu

Blaveri

et al. 2004

Intl Journal of Cancer

View full text Add to dashboard Cite

Transitional cell carcinoma of the urinary bladder remains life threatening due to the high occurrence of metastases. Emerging evidence suggests that chemokines and their receptors play a critical role in tumor metastases. In our study, we performed a systematic analysis of the mRNA and protein expression levels of all 18 chemokine receptors in normal urothelium and bladder cancer. CXCR4 was the only chemokine receptor whose mRNA expression level was upregulated in bladder cancer cell lines as well as in invasive and locally advanced bladder cancer tissue samples (pT2-pT4). In contrast, superficial bladder tumors (pTa and pT1) displayed low CXCR4 expression levels and normal urothelial cells were negative for CXCR4. Immunohistochemistry of a bladder cancer tissue microarray (TMA) confirmed that a subgroup of invasive bladder cancers revealed a high CXCR4 protein expression, while superficial bladder tumors showed low immunoreactivity. To investigate the functional significance of CXCR4 expression, we performed migration and invasion assays. Exposure of CXCR4-positive bladder cancer cells to CXCL12 in a Boyden chamber type assay provoked a significant increase in migration as well as invasion across a Matrigel barrier. Enhanced migration and invasion were inhibited by a CXCR4-specific blocking antibody. In contrast, normal urothelial cells did not respond to CXCL12 and lacked chemotactic migration. In conclusion, bladder cancer cells express CXCR4 progressively with advanced tumorigenesis and this receptor interacts with CXCL12 to mediate tumor chemotaxis and invasion through connective tissue. These properties identify CXCR4 as a potential target for the attenuation of bladder cancer metastases. © 2004 Wiley-Liss, Inc.Key words: chemokine; bladder cancer; metastasis; migration; invasion Transitional cell carcinoma of the bladder is the most frequent tumor of the urinary tract. Despite advances in early detection and therapy, bladder cancer remains life threatening due to the high occurrence of metastases. Radical cystectomy is the preferred treatment for muscle-invasive bladder cancer in the United States, Japan and some countries of Europe. However, at least 50% of patients with locally advanced disease are expected to develop systemic progression within 3 years. 1 Patients suffering from metastatic bladder cancer are commonly treated with systemic chemotherapy. Analyzing survival rates from standard chemotherapy schedules such as M-VAC (methotrexate, vinblastine, adriamycin and cisplatin), results are more or less discouraging. In the Loehrer trial, only 5 of 133 (3.7%) of the patients randomized to M-VAC were alive at the 6-year follow-up time. These results indicate that patients with systemic metastases continue to be incurable by chemotherapy. 2,3 Despite the fact that it is the metastases rather than the primary tumors that cause most cancer deaths, there has been little progress in identifying drugs to specifically block metastases.Metastasis is not a simple phenomenon, but a highly organized process com...

show abstract

Section: Discussionmentioning

confidence: 99%

CXCR4 expression reflects tumor progression and regulates motility of bladder cancer cells

Retz

Sidhu

Blaveri

et al. 2004

Intl Journal of Cancer

View full text Add to dashboard Cite

show abstract

“…None of the groups exhibited normal distribution. Hence each group was first subjected to the non-parametric Mann-Whitney U Test for independent samples [21] to measure the significance of difference, then examined for concordance correlation q c [22], which evaluates the degree to which pairs of observations fall on the 45°line through the origin and contains a measurement of precision q and accuracy C b (q c = qÁC b ) and finally compared using two models of Regression: Deming [23], which takes measurement errors for both methods into account and Passing-Bablok [24], which requires no special assumptions regarding the distribution of the samples and the measurement errors. Based on these findings, Bland-Altman plots [25], where the differences (or alternatively the ratios) between the two techniques are plotted against the averages of the two techniques, were constructed for each group.…”

Section: Statistical Analysesmentioning

confidence: 99%

TSH Comparison Between Chemiluminescence (Architect) and Electrochemiluminescence (Cobas) Immunoassays: An Indian Population Perspective

Sarkar¹

2013

Ind J Clin Biochem

View full text Add to dashboard Cite

Although 3rd generation TSH assays are the most widely used immunoassays, credible comparison studies, specially involving Indian sub-populations are practically non-existent. To compare the TSH measurements between chemiluminescence (Architect) and electrochemiluminescence (Cobas) inmmunoassays in an urban ambulatory Indian population. 1,615 subjects were selected randomly from the usual laboratory workflow, their TSH measured in Architect and Cobas and the paired data thus generated were statistically analysed. TSH values of Cobas were observed to be higher than the Architect values by 28.7 %, with a significant proportional difference between the two, but majority of the Cobas values (above 90 %) were within the limits of agreement with Architect values. In situations where both the instruments are in use simultaneously, a standardization of the methods is imperative, in larger interest of the patient populace.

show abstract

“…Statistical significance of the differences for non-normally distributed data was tested between age groups with the Mann-Whitney U-test. 16 Normal distribution of ELISA data was evaluated by calculating Lilliefors probabilities based on KolmogorovSmirnov test. 17 In order to test the relationship between actual age and cytokine secretion levels, Spearman's rank order correlations were calculated.…”

Section: Tissue Processing and Immunofluorescencementioning

confidence: 99%

Systematic expression profiling of innate immune genes defines a complex pattern of immunosenescence in peripheral and intestinal leukocytes

et al. 2008

View full text Add to dashboard Cite

Immunosenescence is characterized by a quantitative decline of adequate immune responses, which renders the elderly individual particularly susceptible to bacterial, viral and fungal pathogens. Whereas changes of the aging adaptive immune system (for example, reduced immunoglobulin secretion) have been extensively characterized, alterations of the innate immune system are still poorly understood. The aim of the present study was to systematically examine mRNA expression levels of innate immune genes and proinflammatory cytokines in peripheral and intestinal leukocytes of subjects of different ages. In both, whole blood samples and in colonic biopsies most of the Toll-like receptors (TLRs) and nucleotide-binding and oligomerization domain-like receptors (NLRs) transcript levels were significantly downregulated in elderly subjects (90-99 years). Older individuals, when compared to the younger, exhibited an increased expression and/or secretion of proinflammatory cytokines by peripheral and intestinal leukocytes as well as an increased level of nuclear factor-kB activation in colonic biopsies. The observed downregulation of TLRs and NLRs during the aging process may contribute to the lack of effective recognition of invading pathogens or the commensal flora. This effect results in aberrant secondary immune cell activation and could significantly contribute to morbidity and mortality at advanced age.

show abstract

On a Test of Whether one of Two Random Variables is Stochastically Larger than the Other

Cited by 10,735 publications

References 2 publications

CXCR4 expression reflects tumor progression and regulates motility of bladder cancer cells

CXCR4 expression reflects tumor progression and regulates motility of bladder cancer cells

TSH Comparison Between Chemiluminescence (Architect) and Electrochemiluminescence (Cobas) Immunoassays: An Indian Population Perspective

Systematic expression profiling of innate immune genes defines a complex pattern of immunosenescence in peripheral and intestinal leukocytes

Contact Info

Product

Resources

About