Urine screening by Seldi-Tof, followed by biomarker identification, in a Brazilian cohort of patients with Renal Cell Carcinoma (RCC)

Abstract

Purpose: To screen proteins/peptides in urine of Renal Cell Carcinoma (RCC) patients by SELDI-TOF (Surface Enhanced Laser Desorption Ionization -Time of Flight) in search of possible biomarkers. Material and Methods: Sixty-one urines samples from Clear Cell RCC and Papillary RCC were compared to 29 samples of control urine on CM10 chip. Mass analysis was performed in a ProteinChip Reader PCS 4,000 (Ciphergen Biosystems, Fremont, CA) with the software Ciphergen Express 3.0. All chips were read at low and at high laser energy. For statistical analysis the urine samples were clustered according to the histological classification (Clear Cell and Papillary Carcinoma). For identification urine was loaded on a SDS PAGE gel and bands of most interest were excised, trypsinized and identified by MS/MS. Databank searches were performed in Swiss-Prot database using the MASCOT search algorithm and in Profound. Results: Proteins that were identified from urine of controls included immunoglobulin light chains, albumin, secreted and transmembrane 1 precursor (protein K12), mannan--binding lectin-associated serine protease-2 (MASP-2) and vitelline membrane outer layer 1 isoform 1. Identification of immunoglobulins and isoforms of albumin are quite common by proteomics and therefore cannot be considered as possible molecular markers. K12 and MASP-2 play important physiological roles, while vitellite membrane outer layer 1 role is unknown since it was never purified in humans. Conclusions: The down expression of Protein K-12 and MASP-2 make them good candidates for RCC urine marker and should be validated in a bigger cohort including the other less common histological RCC subtypes.

Urinary Signatures of Renal Cell Carcinoma Investigated by Peptidomic Approaches

“…However, none of these groups were able to provide the identity of their markers. Recently Alves et al [36] could cluster RCC patients and controls using a SELDI-TOF approach. They were also able to provide the identity of several protein signals by SDS-PAGE followed by LC-ESI but no information about the diagnostic capability of the outcomes was given.…”

O presente e o futuro dos marcadores circulantes de câncer

“…Nosso grupo, em colaboração com um grupo alemão, e usando a plataforma SELDI-TOF, relatou a subexpressão das proteínas K-12 e MASP-2 em urina de pacientes de carcinoma renal (RCC -do inglês, renal cell carcinoma) de células claras. 40 Esses resultados, embora promissores, precisam ainda ser validados numa coorte maior de pacientes de RCC e células claras (principal tipo histológico), e em outros subtipos de RCC.…”

Genomic Analysis as the First Step toward Personalized Treatment in Renal Cell Carcinoma

“…In their functional assays, STC2 and VCAN were shown to promote cell survival (55). Older research was carried out in 2001 by Takahashi et al, who performed pioneering studies at that time to better understand the molecular mechanisms underlying ccRCC progression (56). This scientific group studied the gene-expression profiles of 29 ccRCC tumors by using 21,632 cDNA microarrays.…”