Method of identifying cancer biomarkers and cancer progression

Abstract

An efficient method for identifying important cancer biomarkers and identifying progression of bladder cancer using pro-u-PA as a clinical tool is provided. Searching for biomarkers critical for bladder carcinoma diagnosis and prognosis, secreted proteomes of highly malignant U1 and pre-malignant U4 cell lines are first analyzed. Proteins in the cultured media of the U1 and U4 cell-lines were systematically examined by SDS-PAGE combined with MALDI-TOF mass spectrometry. Expression of pro-u-plasminogen activator (pro-u-PA) was confirmed by Western blot analysis and further evaluated. A statistically significant relationship between the low level and absence of pro-u-PA in urine with high stages and grades of the tumor samples was established. Constitutive expression of Ras dominant negative protein led to increased expression of pro-u-PA in cultured media, indicating the loss of pro-u-PA is associated with oncogenic transformation. The loss of pro-u-PA in urine has been identified as a marker of more advanced bladder carcinoma.

Description

[0001]This application is a divisional application of, and claims a priority to the U.S. application Ser. No. 11 / 767,511 filed on Jun. 24, 2007, which is incorporated herewith in its entirety.BACKGROUND OF THE INVENTION[0002]1. Field of the Invention[0003]The present invention relates to cancer detection. More specifically, the present invention discloses an efficient method for identifying important cancer biomarkers and identifying cancer progression using loss of pro-u-PA in urine as a marker of more advanced carcinoma.[0004]2. Description of the Prior Art[0005]Transitional cell carcinoma of the bladder is the second most common malignancy of the genitourinary tract and the second most common cause of death from genitourinary tumors. Depending on the depth of muscle invasion, bladder cancers tend to occur in two principal forms: low-grade superficial tumors and high-grade invasive cancer. Superficial bladder cancer accounts for approximately 70% to 80% of all newly diagnosed blad...

AI Technical Summary

Benefits of technology

"The present invention provides an efficient and effective method for detecting the progression of cancer, specifically bladder cancer. The method uses the loss of pro-u-PA in urine as a marker of more advanced carcinoma, which is a poorly understood process that appears to involve genetic and epigenetic factors. The method involves analyzing proteins secreted from bladder cancer cells in cultured-medium and identifying potential markers of carcinogenesis that would form the basis of a test for diagnosis and monitoring prognosis. The method is non-invasive and efficient, and can help in identifying cancer progression at an early stage."

Problems solved by technology

Because of the multifocal nature of urothelial cancers, patients who survive bladder cancer remain at risk of invasive disease.

Most invasive tumors are nodular, metastatic during the early phase, and have poor prognosis.

The major problem with bladder cancers is the high recurrence rate of superficial cancers: more than half of superficial tumors recur within 5 years and 10-20% of these progress to invasive disease.

Cytologic analysis of voided urine is the most commonly used noninvasive method for detecting transitional cell carcinoma, but its utility is severely constrained by its low sensitivity.

Although analysis of these markers allows a more sensitive detection of bladder cancer than urine cytology, their use is limited by low specificity.

However, it has proven difficult to use these genetic alterations as diagnostic markers of bladder cancer because of their low sensitivity.

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