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Akt/protein kinase B signaling is very important for cancer cell survival and growth when cells are exposed to various apoptotic stimuli. Akt is constitutively activated in NSCLC cells and is a potential target for enhancing the cytotoxicity of chemotherapeutic agents in treatment of NSCLC. In our study, we investigated whether down-regulating Akt1 using RNAi techniques can enhance sensitivity to cisplatin in NSCLC cells. An siRNA targeting Akt1 significantly decreased the protein level of Akt1 and the activity of ERK. Treatment of these cells with 20 lM cisplatin increased apoptotic cell death 2.6-fold compared to cells transfected with a scrambled siRNA. While Akt activity was slightly reduced, ERK activity was greatly increased in cells treated with cisplatin alone. Pretreatment of these cells with the selective MEK inhibitor U0126 effectively reduced the level of cisplatin-induced apoptosis. These results imply that cisplatin-induced MEK/ERK activation appears to mediate apoptotic cell death, but that constitutively activated Akt1 and/or ERK pathway may mediate resistance to cisplatin in NSCLC cells. Taken together, our data demonstrate that down-regulation of Akt1 using RNAi enhances the chemosensitivity of NSCLC cells to cisplatin. ' 2008 Wiley-Liss, Inc.Key words: Akt1; siRNA; non-small cell lung cancer; cisplatin Lung cancer is a highly aggressive and challenging cancer that currently is the leading cause of cancer deaths throughout the world. Cisplatin-based doublet chemotherapy, in which patients are treated with a combination of cisplatin and a second chemotherapeutic agent, is a standard regimen for advanced non-small cell lung cancer (NSCLC). Although advances in chemotherapy have provided improvements in overall survival in advanced NSCLC, the development of chemoresistance is a major hurdle limiting treatment success.Akt forms as a hub in cell signaling pathways controlling cell survival and cell death. The Akt pathway promotes cell survival, migration, proliferation and angiogenesis. Akt activation is one of the most common molecular alterations in cancer and contributes to tumorigenesis, as well as promoting resistance to chemotherapy.1-3 Direct inhibition of Akt is a potential target for enhancing apoptosis in response to chemotherapeutic agents in NSCLC.Cisplatin activates Akt and/or the extracellular signal-regulated kinase (ERK) in various cell types. Many studies have shown that activation of Akt and/or ERK is associated with an increase in cell survival in cisplatin-treated cells. 4 However, other studies have suggested that ERK signaling plays a role in the induction of apoptosis by cisplatin.5 Therefore, whether Akt and/or ERK signaling is associated with the induction of apoptosis or with cell survival in cisplatin-treated NSCLC cells remains unresolved.In our study, we have investigated whether down-regulating Akt1 by RNA interference (RNAi) in NSCLC cells enhances the sensitivity to cisplatin through a decrease in ERK activity. Material and methods ReagentsCisplatin was obtained from...

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Abstract. Cathepsin L (CTSL) is a lysosomal cysteine protease that has been found to be overexpressed in ovarian cancer (OC). The aim of the present study was to investigate the possible involvement of CTSL in the development of OC. In this study, RNA interference with a CTSL small hairpin RNA (CTSL-shRNA), and a plasmid carrying CTSL were used to identify the effects of this enzyme on the regulation of the malignant behavior of OC cells. OV-90 and SKOV3 human ovarian cancer cell lines were selected as cell models in vitro and in vivo. The results showed that downregulation of CTSL significantly inhibits the proliferative and invasive capability of SKOV3 cells, and that upregulation of CTSL in OV-90 cells leads to opposite effects. Compared with parental OC cells, cells in which CTSL was silenced exhibited a reduced capacity to develop into tumors in nude mice, while the growth of tumor xenografts derived from these cells was markedly constrained. In conclusion, the results suggested that CTSL contributes to the proliferation and metastasis of OC, and that CTSL may be a novel molecular target for OC treatment.

Abstract. The collagen matrix constitutes the primary extracellular matrix (ECM) portion of mammalian connective tissues in which the interaction of the cell and the surrounding collagen fibers has a significant impact on cell and tissue physiology, including morphogenesis, development and motility. Discoidin domain receptors (DDR1 and DDR2) have been identified as the receptor tyrosine kinases that are activated upon collagen binding. However, there is a lack of evidence regarding the effect of DDRs on the mechanical interaction between fibroblasts and ECM. In this study, we demonstrated that one of the major phosphotyrosine proteins in human fibroblasts during 3D collagen matrix polymerization is DDR2. Treatment of fibroblasts in 3D collagen matrices with plateletderived growth factor (PDFG) has been shown to increase DDR2 phosphorylation. Silencing of DDR2 with siRNA in fibroblasts significantly reduced the number of dendritic extensions regardless of whether cells were cultured in the collagen or fibronectin 3D matrices. Decreasing dendritic extensions in DDR2-silenced cells has also been shown to decrease the ability of fibroblast entanglement to collagen fibrils in 3D collagen matrices. Finally, we also showed that the silencing of DDR2 decreased the cell migration in 3D nested collagen matrices but had no effect on 3D floating matrix contraction. Collectively, these results suggest that DDR2 functioning is required for the membrane dynamics to control the mechanical attachment of fibroblasts to the 3D collagen matrices in an integrin-independent manner.

Compound 1, as a KPNB1 inhibitor, might be a good target for future development of anticancer agents showing the activities of apoptosis and cell cycle arrest.

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Members of the Mongol imperial family (designated the Golden family) are buried in a secret necropolis; therefore, none of their burial grounds have been found. In 2004, we first discovered 5 graves belonging to the Golden family in Tavan Tolgoi, Eastern Mongolia. To define the genealogy of the 5 bodies and the kinship among them, SNP and/or STR profiles of mitochondria, autosomes, and Y chromosomes were analyzed. Four of the 5 bodies were determined to carry the mitochondrial DNA haplogroup D4, while the fifth carried haplogroup CZ, indicating that this individual had no kinship with the others. Meanwhile, Y-SNP and Y-STR profiles indicate that the males examined belonged to the R1b-M343 haplogroup. Thus, their East Asian D4 or CZ matrilineal and West Eurasian R1b-M343 patrilineal origins reveal genealogical admixture between Caucasoid and Mongoloid ethnic groups, despite a Mongoloid physical appearance. In addition, Y chromosomal and autosomal STR profiles revealed that the four D4-carrying bodies bore the relationship of either mother and three sons or four full siblings with almost the same probability. Moreover, the geographical distribution of R1b-M343-carrying modern-day individuals demonstrates that descendants of Tavan Tolgoi bodies today live mainly in Western Eurasia, with a high frequency in the territories of the past Mongol khanates. Here, we propose that Genghis Khan and his family carried Y-haplogroup R1b-M343, which is prevalent in West Eurasia, rather than the Y-haplogroup C3c-M48, which is prevalent in Asia and which is widely accepted to be present in the family members of Genghis Khan. Additionally, Tavan Tolgoi bodies may have been the product of marriages between the lineage of Genghis Khan’s Borjigin clan and the lineage of either the Ongud or Hongirad clans, indicating that these individuals were members of Genghis Khan’s immediate family or his close relatives.