Lung cancer is a common malignancy and has a poor overall prognosis. Widespread metastasis is a common phenomenon in non-small cell lung cancer (NSCLC). It has been demonstrated that cancer relapse and survival can be predicted by the presence of a five-microRNA (miRNA) signature independent of stage or histologic type in NSCLC patients. Among the five miRNAs in the signature, miR-372 has been shown to play a significant role in metastasis and in the development of human testicular germ cell tumors. In addition, there is evidence that miR-372 posttranscriptionally downregulates large tumor suppressor, homolog 2 (Lats2), resulting in tumorigenesis and proliferation. To further investigate the cellular mechanisms involved in miR-372-induced silencing, we conducted a comparative proteomic analysis of NSCLC CL 1-0 cells expressing miRNA-372 and/or vector only by using two-dimensional gel electrophoresis (2DE), two-dimensional difference gel electrophoresis (2D-DIGE), and LC/MS/MS. Proteins identified as being up- or downregulated were further classified according to their biological functions. Many of the proteins identified in our study may be potential diagnostic biomarkers of NSCLC, particularly phosphorylated eIF4A-I.

Chondrocytes are the only cell type present in mature articular cartilage (2-5% of total tissue). The biological activities of the chondrocyte population are regulated by genetic, biologic and biochemical factors, as well as environmental factors (stress, flow and electric field). Although compressive forces within joint articular cartilage are required for maintenance of the normal composition of articular cartilage, there is a lack of knowledge about the number of pressure-related proteins expressed in articular cartilage. Two-dimensional gel electrophoresis (2-DE) and high-performance liquid chromatography-electrospray/tandem mass spectrometry (HPLC/ESI-MS/MS) were used to identify the levels of pressure-related proteins expressed by chondrocytes grown in the presence or absence of hydrostatic pressure. A total of 266 spots were excised from the gels and analyzed by HPLC/ESI-MS/MS. Functional classification of up-regulated proteins indicated that energy and protein fate were the main biological processes occurring in pressurized chondrocytes. Furthermore, membrane-bound transferrin-like protein p97, a marker of chondrocyte differentiation, was only expressed in chondrocytes under hydrostatic pressure. These data suggest that hydrostatic pressure can induce cell differentiation by increasing the expression level of energy metabolism- and protein fate-related proteins, indicating that hydrostatic pressure may be needed for normal biosynthesis and differentiation of articular chondrocytes.