The intermediates obtained from thermal decomposition of Zn/Cr-layered double hydroxide carbonates (Zr/Cr-LDH; Zn0.66Cr0.34(OH)2(CO3)0.170.57H2O) were studied by XRD, TPD, FT-IR, ESCA and chemical analyses. It was found that Cr(III) ions embedded originally in the hydroxide layers were oxidized to Cr(VI) species in the temperature range between 473 and 773 K where the layer structure was lost, and reduced again to Cr(III) in the spinel phase over 773 K.

Lung neoplasia is a major cause of death in cancer patients throughout the world. Diagnostic techniques and therapeutic modalities for lung cancer patients have been improved over the past decade; however, the overall death rate is still high. 1) Despite undergoing curative surgical treatment, many patients develop recurrent disease and most of such recurrent disease includes distant metastasis.2, 3) Therefore, controlling metastatic disease is one of the important problems that must be addressed in order to conquer lung neoplasia.Among the various clinicopathological factors, lymphatic metastasis is one of the most critical factors for the prognosis of lung cancer patients. [4][5][6] Although experimental models for lung cancer have been reported by several investigators, these models have included some important drawbacks, such as ectopic implantations and complicated procedures.7-9) Recently, we established a model of spontaneous lymphatic metastasis produced by orthotopic implantation of lung cancer cells.10) Direct implantation of Lewis lung carcinoma (LLC) admixed with "MATRIGEL" into the left lobe of the lung caused the formation of a solitary tumor followed by metastasis to the mediastinal lymph node. This model should be useful for investigating therapeutic approaches for lung cancer disease in preclinical studies.We have reported that 4-[3,5-bis(trimethylsilyl)benzamido]benzoic acid, TAC-101, abolished activating protein-1 (AP-1) binding to consensus DNA and inhibited the experimental liver metastasis of gastrointestinal tract cancer in animal models.11) AP-1 has been reported to be a major transcriptional enhancer for the expression of urokinase-type plasminogen activator, overexpression of which has been reported to be correlated with lymphatic metastasis of lung cancer. [12][13][14][15][16] In the present study, we investigated the effects of TAC-101 on the growth at the implantation site and the spontaneous lymphatic metastasis caused by the orthotopic implantation of LLC, and we examined its anti-metastatic mechanism of action in vitro. Since platinum agents have been used as standard treatment modalities for lung cancer, 1,17,18) combination therapy of TAC-101 and CDDP in the LLC model was also examined.