Heat shock protein (HSP) induction confers protection against diverse forms of cellular and tissue injury. However, the mechanism by which HSP exerts cytoprotective effects is unclear. Because HSP induction inhibits genetic expression of pro-inflammatory cytokines, the transcription of which is dependent on NF-κB activation, we explored the relationship between the anti-inflammatory effect of HSP induction and the NF-κB/IκBα pathway. Both HS and sodium arsenite treatment increased HSP70 expression time dependently at mRNA and protein levels. Prior induction of HSP suppressed cytokine-induced IL-8 and TNF-α expression at both mRNA and protein levels. Although HSP induction did not affect total cellular expression of NF-κB, TNF-α-induced increase in NF-κB-DNA binding activity and nuclear translocation of the p65 subunit of NF-κB were inhibited by prior HSP induction, suggesting that activation of NF-κB was blocked. Cytokine-induced IκBα phosphorylation and its degradation were blocked in HSP-induced cells. Immune complex kinase assays demonstrated that TNF-α induced increase in IκB kinase activity was suppressed by prior HSP induction. These results suggest that the anti-inflammatory effect of HSP induction in respiratory epithelial cells is related to stabilization of IκBα, possibly through the prevention of IκB kinase activation, which thereby inhibits activation of NF-κB.

Uteroglobin is a secretory protein synthesized by most epithelia, including the respiratory tract. It has strong anti-inflammatory properties that appear to be related to the inhibition of phospholipase A2. Recent experimental evidence indicates that uteroglobin has an inhibitory effect on the proliferation and invasion of cancer cells. We investigated the effects of the adenovirusuteroglobin (ad-UG) transduction on the growth of lung cancer cell lines, which did not express the uteroglobin gene. Upon transduction of ad-UG, the rate of cell growth and the ability to produce colonies in soft agar were evaluated. Cell cycle analysis, Western blot for cell cycle-related proteins and annexin V staining for apoptosis were carried out to see if they were associated with the changes in cell growth. All the tested lung cancer cell lines did not express the uteroglobin gene. The growth rates, and colonyforming ability of transformed cells, were significantly inhibited by the induction of uteroglobin gene expression. The DNA histogram showed that the cell fraction of the G2/M phase was increased, and this G2/M phase arrest was related to a decrease of cdk1 and cyclin A. However, a fraction of apoptotic cells were same as the control. From these results, uteroglobin is thought to have an inhibitory effect on the growth of lung cancer cells. This suggests a potential role for uteroglobin in gene therapy for lung cancer.

The fragile histidine triad (FHIT) gene is a frequent target of deletions in lung cancer. Previous studies have shown that FHIT gene transfer into lung cancer cells lacking FHIT expression results in induction of apoptosis. However, the effect of FHIT expression on apoptosis induced by chemotherapeutic agents and its intracellular mechanism is poorly understood. This study was undertaken to elucidate the effect of FHIT expression and the role of Bcl-2-caspase signaling in paclitaxel-induced apoptosis in lung cancer cells. NCI-H358 lung cancer cells, which lack FHIT expression, were stably transfected with plasmid vector containing FLAGtagged wildtype FHIT. We investigated effects of paclitaxel on apoptosis, activation of caspase system and expression of Bcl-2 family. We next evaluated whether these effects were reversed by blocking FHIT expression using siRNA. Paclitaxel enhanced apoptosis in FHIT-expressing cells compared to that in control vectortransfected cells, and this enhancement was suppressed by siRNA treatment. Activities of caspase-3 and caspase-7, but not of caspase-8, were higher in FHIT-expressing cells than in control vector-transfected cells, and this was reduced by siRNA treatment. When caspase activation was blocked by a pan-caspase inhibitor in FHIT-expressing cells, paclitaxel-induced apoptotic cell death was decreased similar to that in control vector-transfected cells. Bcl-2 and Bcl-xL expressions were down-regulated after paclitaxel treatment in FHIT-expressing cells, whereas Bax and Bad expressions were up-regulated. These were reversed by siRNA treatment. These results indicate that paclitaxel-induced apoptosis enhanced by FHIT expression in lung cancer cells might be associated with modulation of Bcl-2-caspase signaling. ' 2005 Wiley-Liss, Inc.Key words: fragile histidine triad (FHIT); paclitaxel; apoptosis; Bcl-2 protein; lung neoplasms Deletion of human chromosome 3p is one of the most frequently found genetic alterations in lung cancers, observed in more than 90% of small cell lung cancers and in about 80% of non-small cell lung cancers. [1][2][3][4] Further, it is known that chromosome 3p deletions occur even in an early stage of lung carcinogenesis including hyperplasia, dysplasia or carcinoma in situ. 5,6 Thus, chromosome 3p has been proposed to contain tumor suppressor genes of lung cancer, and several candidate genes have been identified. 7-10 The fragile histidine triad (FHIT) gene is located at 3p14.2 11 and its gene product, FHIT protein, is a diadenosine triphosphate (Ap3A) hydrolase belonging to the histidine triad superfamily of nucleotide-binding proteins. 12,13 Numerous studies have shown the FHIT gene is a frequent target of deletions associated with abnormal RNA and protein expression in primary tumors and cell lines of lung, esophageal, head and neck, cervical and breast cancer. [14][15][16][17] In lung cancer, FHIT inactivation has been detected very frequently. [18][19][20] For example, 80% of small cell lung cancers and 40% of non-small cell lung cancers showed abn...