The Role of Targeted Agents in the Treatment of Metastatic Breast Cancer

Expression of Protein 4.1 Family in Breast Cancer: Database Mining for 4.1 Family Members in Malignancies

BACKGROUND The protein 4.1 family is a family of cytoskeletal proteins that play an important role in maintaining normal cell morphology and cell adhesion, migration, division, and intercellular signaling. The main aim of this study was to explore the prognostic significance of the protein 4.1 family in breast cancer (BC) patients and to provide new biomarkers and therapeutic targets for the diagnosis and treatment of BC. MATERIAL AND METHODS The expression of 4.1 family members in various tumor types was compared to normal controls using the ONCOMINE and GOBO databases. The prognostic significance of the 4.1 family in BC patients was determined by Kaplan-Meier Plotter. RESULTS EPB41L2 (4.1G) was expressed at higher levels in normal tissues compared with BC patients for all 4.1 family members. In survival analysis, 4.1G and EPB41 (4.1R) mRNA high expressions were associated with better survival in BC patients. Moreover, 4.1G high expression was significantly associated with longer overall survival (OS) in luminal A and protracted relapse-free survival (RFS) in luminal B subtype BC patients who received Tamoxifen treatment. In addition, high expression of each 4.1 family member also showed better prognostic value in different molecular subtypes of BC. CONCLUSIONS These results indicate that the protein 4.1 family can be regarded as novel biomarkers and potential therapeutic targets for BC. Further research is needed to explore the detailed biological functions.

Photoactivatable Caged Prodrugs of VEGFR-2 Kinase Inhibitors

In this study, we report on the design, synthesis, photokinetic properties and in vitro evaluation of photoactivatable caged prodrugs for the receptor tyrosine kinase VEGFR-2. Highly potent VEGFR-2 inhibitors 1 and 3 were caged by introduction of a photoremovable protecting group (PPG) to yield the caged prodrugs 4 and 5. As expected, enzymatic and cellular proliferation assays showed dramatically diminished efficacy of caged prodrugs in vitro. Upon ultraviolet (UV) irradiation of the prodrugs original inhibitory activity was completely restored and even distinctly reinforced, as was the case for the prodrug 4. The presented results are a further evidence for caging technique being an interesting approach in the protein kinase field. It could enable spatial and temporal control for the inhibition of VEGFR-2. The described photoactivatable prodrugs might be highly useful as biological probes for studying the VEGFR-2 signal transduction.

[Targeted based therapies in metastatic breast cancer: future evolution]

Research on molecular alteration process mechanisms leading to cancerogenesis permitted the elaboration of many targeted therapies. Some therapeutic classes appeared recently and are currently being tested, including HER-2 dimerization inhibitors. However, most of these therapies are mostly ineffective with monotherapy. Clinical trials are ongoing, testing their efficiency in association with other molecules of the therapeutic arsenal which is available in oncology. Nevertheless, breast cancer remains a pathology life-threatening, most of the time. Within this review will be introduced the most efficient of these targeted therapies, including their eventual association with other cytotoxic molecules.