title: Identification of protein clusters predictive of response to chemotherapy in breast cancer patients.
abstract: An attempt for the identification of potential biomarkers predictive of response to chemotherapy (CHT) in breast cancer patients has been performed by the use of two-dimensional electrophoresis and mass spectrometry analysis. Since growth and progression of tumor cells depend also on stromal factors in the microenvironment, we choose to investigate the proteins secreted in Tumor Interstitial Fluid (TIF) and in Normal Interstitial Fluids (NIF). One-hundred and twenty-two proteins have been analyzed and a comparison was also made between the proteomic profile of responders versus nonresponders to CHT. At baseline, proteins isolated in TIF and NIF of all the 28 patients show significant differences in expression. Two clusters of proteins, differentially expressed in TIF with respect to NIF were found. Most significant is the decreased expression in TIF of CRYAB. In the protein metabolism group, also FIBB was found decreased. Some proteins involved in energy pathways were overexpressed (PGAM-1, ALDO A, PGK1, G3Pcn), while some other were down-regulated (CAH2, G3Pdx, PRDX6, TPIS). The same trend was observed for signal transduction proteins, with 14-3-3-Z overexpressed, and ANXA2 and PEBP 1 down-regulated. Moreover, an analysis has been conducted comparing protein expression in interstitial fluids of responders and nonresponders, irrespective of TIF or NIF source. This analysis lead us to identify two clusters of proteins with a modified expression, which might be predictive of response to CHT. In responders, an increase in expression of LDHA, G3Pdx, PGK1sx (energy pathways), VIME (cell growth and maintenance) and 14-3-3-Z (signal transduction), coupled with a decreased expression of TPIS, CAH 2, G3Psx, PGK 1dx (energy pathways), TBB5 (cell growth and maintenance), LDHB and FIBB (protein metabolism), was found. We observed that CHT modifies the expression of these cluster proteins since, after treatment, their expression in TIF of responder is generally decreased. Patients not responding to CHT show an unchanged expression pattern in TIF, with the exception of protein 14-3-3-Z, which is overexpressed, and a decreased expression in NIF of several cluster proteins. In conclusion, the identification of protein clusters associated with response to CHT might be important for predicting the efficacy of a specific antineoplastic drug and for the development of less empiric strategies in choosing the therapy to be prescribed to the single patient.
authors.affiliation: Department of Oncology & Haematology, University of Modena and Reggio Emilia, Modena, Italy.
authors.forename: Laura
authors.initials: L
authors.lastname: Cortesi
authors.forename: Andrea
authors.initials: A
authors.lastname: Barchetti
authors.forename: Elisabetta
authors.initials: E
authors.lastname: De Matteis
authors.forename: Elena
authors.initials: E
authors.lastname: Rossi
authors.forename: Lara
authors.initials: L
authors.lastname: Della Casa
authors.forename: Luigi
authors.initials: L
authors.lastname: Marcheselli
authors.forename: Giovanni
authors.initials: G
authors.lastname: Tazzioli
authors.forename: Maria Grazia
authors.initials: MG
authors.lastname: Lazzaretti
authors.forename: Guido
authors.initials: G
authors.lastname: Ficarra
authors.forename: Massimo
authors.initials: M
authors.lastname: Federico
authors.forename: Anna
authors.initials: A
authors.lastname: Iannone
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000970:Antineoplastic Agents / Q000627:therapeutic use*; D014408:Biomarkers, Tumor / Q000032:analysis*; D001943:Breast Neoplasms / Q000737:chemistry / Q000188:drug therapy / Q000378:metabolism; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D016000:Cluster Analysis; D015180:Electrophoresis, Gel, Two-Dimensional / Q000379:methods; D045604:Extracellular Fluid / Q000737:chemistry*; D005260:Female; D015972:Gene Expression Regulation, Neoplastic; D006801:Humans; D008875:Middle Aged; D008969:Molecular Sequence Data; D009363:Neoplasm Proteins / Q000737:chemistry / Q000378:metabolism; D016896:Treatment Outcome; D055815:Young Adult
chemical_list: D000970:Antineoplastic Agents; D014408:Biomarkers, Tumor; D009363:Neoplasm Proteins