In tobacco (Nicotiana tabacum), nicotine is the predominant alkaloid. It is produced in the roots and accumulated mainly in the leaves. Jasmonates play a central signaling role in damage-induced nicotine formation. The genome sequence of tobacco provides us an almost complete inventory of structural and regulatory genes involved in nicotine pathway. Phylogenetic and expression analyses revealed a series of structural genes of the nicotine pathway, forming a regulon, under the control of jasmonate-responsive ETHYLENE RESPONSE FACTOR (ERF) transcription factors. The duplication of NAD and polyamine metabolic pathways and the subsequent recruitment of duplicated primary metabolic genes into the nicotine biosynthesis regulon were suggested to be the drivers for pyridine and pyrrolidine ring formation steps early in the pathway. Transcriptional regulation by ERF and cooperatively acting MYC2 transcription factors are corroborated by the frequent occurrence of cognate cis-regulatory elements of the factors in the promoter regions of the downstream structural genes. The allotetraploid tobacco has homologous clusters of ERF genes on different chromosomes, which are possibly derived from two ancestral diploids and include either nicotine-controlling ERF189 or ERF199. A large chromosomal deletion was found within one allele of the nicotine-controlling NICOTINE2 locus, which is part of one of the ERF gene clusters, and which has been used to breed tobacco cultivars with a low-nicotine content.

It has recently been shown that an insertion (I)/deletion (D) polymorphism exists in the angiotensin-converting enzyme (ACE) gene, and that this polymorphism affects the serum ACE level. There are three genotypes: DD, DI, and II, with the ACE level highest in DD, intermediate in DI, and lowest in II. In the present investigation of the possible significance of the polymorphism for sarcoidosis, a total of 207 patients and 314 normal control subjects were examined. There were no significant differences in the I/D ratio and the genotype distribution between the two groups, and no significant variation in organ involvement (i.e., eye, skin, and heart) was noted among the three genotypes. To determine any prognostic influence of the polymorphism, we examined the disappearance ratio of abnormal shadow on chest radiography over 3 and 5 yr. No significant difference among the three genotypes was observed. New normal ranges of serum ACE level were determined for each genotype, and found to be 22% more sensitive overall than the conventional normal range and 39% more so for II type, suggesting an advantage for diagnosis and assessment of the disease activity of sarcoidosis.

Small cell lung cancer (SCLC) cell lines specifically express ganglioside GD2, and anti-GD2 monoclonal antibodies (mAbs) caused suppression of cell growth and induced apoptosis of SCLC cells with single use. Here, enhancement of the cytotoxic effects of various anti-cancer drugs with an anti-GD2 mAb was demonstrated. The cytotoxicity of all six drugs examined was markedly enhanced, i.e. 2.4-7.8-fold increase of cell sensitivity in terms of IC 50 . In particular, the combination of cisplatin (CDDP) with an anti-GD2 mAb resulted in prominent enhancement of cytotoxicity even in low-moderate GD2-expressing lines. The anti-GD2 mAb induced weak activation of c-Jun terminal kinase (JNK) in SCLC cells, and all anti-cancer drugs also induced its activation to various degrees. When CDDP and an anti-GD2 mAb were used together, significantly stronger JNK activation was observed corresponding to the cytotoxic effects, suggesting that synergistic phosphorylation of JNK with two reagents induced prominent apoptosis. The essential role of JNK in the induction of SCLC apoptosis with CDDP and anti-GD2 mAb was confirmed by experiments with a JNK inhibitor, curcumin. These results suggest that anti-GD2 mAbs would be very efficient in combination with anti-cancer drugs, both to achieve SCLC-specific cytotoxicity and to enhance its magnitude. Key words: Apoptosis -Small cell lung cancer -Chemotherapy -JNK -GD2Gangliosides are enriched in nervous tissues of vertebrates 1) and their expression is spatio-temporally regulated.2) In human malignant tumor cells, neuroectodermderived tumor cells such as melanomas, neuroblastomas, and gliomas frequently express characteristic gangliosides for individual tumor types.3-6) Sarcomas, 7) gastric cancers, 8,9) T cell leukemias [10][11][12] and small cell lung cancer (SCLC) cells 13) also express specific gangliosides. Specific monoclonal antibodies (mAbs) to these tumor-associated ganglioside antigens have been utilized for diagnosis, 14,15) prediction of the prognosis, 16,17) and detection of residual tumors.18) In particular, anti-ganglioside mAbs have been tried for immunotherapy of melanomas 19,20) and neuroblastomas. 21)During the early stage of mAb application, anti-GD3 mAb R24 was used for the first time in the treatment of recurrent melanomas, and showed the ability to reduce the tumor size or halt the progression.19) Anti-GD2 mAb was also applied in the treatment of neuroblastomas to extend remission.22) Moreover, a human mAb reactive with GD2 was tried for cutaneous melanomas with some effects. 20)However, further development of antibody therapy has not been successful mainly due to xenogeneic immunogenicity of mouse antibodies and poor penetration of antibodies into tumor tissues.Recently, application of mAbs for the treatment of various cancers has been re-evaluated based on the progress in recombinant molecular technology and protein engineering with site-directed mutagenesis. Anti-c-erbB2/HER2/neu mAb was used in the therapy of advanced stages of breast cancers 23) and anti-CD20 mAb ...