Propagermanium Induces NK Cell Maturation and Tends to Prolong Overall Survival of Patients With Refractory Cancer.

BACKGROUND/AIM: Propagermanium (PG) inhibits the CCL2/CCR2 axis, and has been shown to function as an immune modulator. This study investigated its anti-tumor mechanism in patients with refractory cancers. MATERIALS AND METHODS: Five healthy volunteers and 23 patients with refractory oral (n=8) or gastric (n=15) cancer received PG (30 mg/day). We performed flow cytometry (FCM) of peripheral blood mononuclear cells and in vitro killing assays. RESULTS: FCM revealed that CD16+/CD56Dim NK cells (i.e., mature, cytolytic subset) increased, and the apoptosis induction rate of cancer cells increased after PG administration. Among gastric cancer patients, median OS was 172.0 days. Two patients showed complete remission of lung or liver metastasis. Survival of patients with oral cancer also tended to be prolonged. CONCLUSION: PG induces NK cell maturation, and may potentiate anti-tumor activity.

Molecular analysis of keratocystic odontogenic tumor cell lines derived from sporadic and basal cell nevus syndrome patients.

Keratocystic odontogenic tumor (KCOT) is a benign tumor often associated with basal cell nevus syndrome (BCNS). Mutations in Patched 1 (PTCH1), the Hedgehog (Hh) receptor, are responsible for BCNS. BCNS is distinguished by morphological anomalies and predisposition to benign and malignant tumors, including medulloblastoma, basal cell carcinoma, KCOT and ovarian fibromas. Among these tumors, KCOT is the least well studied because a suitable model system is not available for its investigation. To enable KCOT to be studied, we established two KCOT cell lines, one from a BCNS case (designated as iKCOT1) and one from a sporadic KCOT case (designated as sKCOT1). The BCNS­derived KCOT cell line, iKCOT1, retained a germline-mutated PTCH1 allele and a wild-type PTCH1 allele. The sporadic KCOT-derived KCOT cell line, sKCOT1, had different loss-of-function PTCH1 mutations on both alleles. Both cell lines expressed stem cell markers (CD44, SOX2 and BMI1), mesenchymal cell markers (CDH2, VIM and SNAI2) and a neurogenic marker (NEFL). Culture of the cell lines in high calcium concentration media induced expression of epithelial cell and keratinocyte marker proteins (CDH1, CLDN1, KRT10 and IVL). Parakeratosis, which is characteristic for KCOTs, was observed in 2-D cultures. The similarities in protein expression patterns between the two cell lines suggested that common mechanisms underlie the development of both types of KCOT and a probable common origin of KCOT cells.

Caffeic acid production by simultaneous saccharification and fermentation of kraft pulp using recombinant Escherichia coli.

Caffeic acid (3,4-dihydroxycinnamic acid) serves as a building block for thermoplastics and a precursor for biologically active compounds and was recently produced from glucose by microbial fermentation. To produce caffeic acid from inedible cellulose, separate hydrolysis and fermentation (SHF) and simultaneous saccharification and fermentation (SSF) reactions were compared using kraft pulp as lignocellulosic feedstock. Here, a tyrosine-overproducing Escherichia coli strain was metabolically engineered to produce caffeic acid from glucose by introducing the genes encoding a 4-hydroxyphenyllactate 3-hydroxylase (hpaBC) from Pseudomonas aeruginosa and tyrosine ammonia lyase (fevV) from Streptomyces sp. WK-5344. Using the resulting recombinant strain, the maximum yield of caffeic acid in SSF (233 mg/L) far exceeded that by SHF (37.9 mg/L). In the SSF with low cellulase loads (≤2.5 filter paper unit/g glucan), caffeic acid production was markedly increased, while almost no glucose accumulation was detected, indicating that the E. coli cells experienced glucose limitation in this culture condition. Caffeic acid yield was also negatively correlated with the glucose concentration in the fermentation medium. In SHF, the formation of by-product acetate and the accumulation of potential fermentation inhibitors increased significantly with kraft pulp hydrolysate than filter paper hydrolysate. The combination of these inhibitors had synergistic effects on caffeic acid fermentation at low concentrations. With lower loads of cellulase in SSF, less potential fermentation inhibitors (furfural, 5-hydroxymethyfurfural, and 4-hydroxylbenzoic acid) accumulated in the medium. These observations suggest that glucose limitation in SSF is crucial for improving caffeic acid yield, owing to reduced by-product formation and fermentation inhibitor accumulation.