Human peripheral blood granulocytes and myeloid leukemic cell lines express both transcripts encoding for stem cell factor

ADAM8: a new therapeutic target for asthma

BACKGROUND

A proteinase with a disintegrin and a metalloproteinase domain-8 (ADAM8) has been linked to asthma.

OBJECTIVE

To explore whether ADAM8 is a therapeutic target for asthma.

METHODS

We reviewed literature on ADAM8's function and expression and activities in lungs of humans and mice with allergic airway inflammation (AAI). We used these data to generate hypotheses about the contributions of ADAM8 to asthma pathogenesis.

CONCLUSIONS

ADAM8 levels are increased in airway epithelium and airway inflammatory cells in mice with AAI and human asthma patients. Data from murine models of AAI indicate that ADAM8 dampens airway inflammation. It is not clear whether ADAM8 contributes directly to structural remodeling in asthmatic airways. Additional studies are required to validate ADAM8 as a therapeutic target for asthma.

Bone morphogenetic protein 15 (BMP15) alleles predict over-response to recombinant follicle stimulation hormone and iatrogenic ovarian hyperstimulation syndrome (OHSS)

OBJECTIVE

Controlled ovarian stimulation (COS) using recombinant follicle-stimulating hormone (rFSH) is the main treatment in assisted reproduction. We performed a pharmacogenetic analysis of bone morphogenetic protein 15 (BMP15) gene using single nucleotide polymorphisms (SNPs) in COS. We also investigated the role of the BMP15 gene in ovarian hyperstimulation syndrome (OHSS).

METHODS

We analysed different intragenic SNPs located within the BMP15 gene in 307 women treated with rFSH, evaluating its involvement in COS outcome.

RESULTS

First, we analysed two polymorphisms, by applying different tests for genetic association, and we found a minimum P-value in patients producing > or =12 follicles in COS (high responders) in both polymorphisms of the BMP15 gene. Using bi-directional DNA sequencing, we identified two additional single nucleotide DNA variants. Second, we conducted association studies with all polymorphisms together, and noticed that none of them seemed to fully explain the association of the BMP15 gene with over-response to rFSH. However, N103S missense mutation is predicted to disrupt the secondary structure of human BMP15 protein and is weakly associated with OHSS. This coding mutation of the BMP15 gene may partially explain the results obtained during our research. Using Thesias software, we reconstructed haplotypes with the four intragenic variants and calculated their frequencies in normal and over-responders to rFSH. The haplotype TGGA was over-represented in high responders when compared with the rest of patients. Moreover, this association was higher in patients with OHSS, with a significant global haplotypic effect of the BMP15 gene.

CONCLUSION

Our results suggest a direct relationship between increased follicle production during COS and BMP15 alleles in response to rFSH in humans. The use of BMP15 markers to prevent OHSS is also a possibility that requires thorough evaluation.

SCF, IL-1beta, IL-1ra and GM-CSF in the bone marrow and serum of normal individuals and of AML and CML patients

This study compared cytokine transcript and protein levels in BM cells of normal individuals and leukemic patients. AML differed from normal in that: (1) AML marrow cells contain more IL-1beta protein than normal cells, (2) IL-1ra transcripts are absent from AML marrow cells, (3) AML marrow serum contains less IL-1ra protein than normal, (4) peripheral blood and marrow serum of AML patireents contains more SCF protein than normal serum, and (5) SCF transcripts have been detected in AML marrow biopsies and not in aspirate cells. These data suggest that unbalanced cytokine production may make a significant contribution to the abnormal behaviour of AML cells.

Expression of SCF splice variants in human melanocytes and melanoma cell lines: potential prognostic implications

Stem cell factor (SCF), the ligand for c-Kit, is known to regulate developmental and functional processes of haematopoietic stem cells, mast cells and melanocytes. Two different splice variants form predominantly soluble (sSCF or SCF-1) and in addition some membrane-bound SCF (mSCF or SCF-2). In order to explore the prognostic significance of these molecules in melanoma, total SCF, SCF splice variants and c-Kit expression were studied in normal skin melanocytes and in 11 different melanoma cell lines, using reverse transcription polymerase chain reaction, immunocytochemistry and enzyme-linked immunosorbent assay. Nine of the 11 melanoma cell lines expressed SCF-1 mRNA, only two of them SCF-2, and these two also SCF-1. Coexpression of both SCF-1 and c-Kit was noted in five cell lines, and only one cell line as well as normal melanocytes expressed both SCF-1 and SCF-2 as well as c-Kit. Corresponding results were obtained on immunocytochemical staining. Of three exemplary melanoma cell lines studied, two expressing SCF mRNA also released SCF spontaneously and on stimulation, whereas the line lacking SCF and c-kit mRNA (SK-Mel-23) failed to do so. These data demonstrate thus that melanoma cell lines, particularly those known to metastasize in vivo, lose the ability to express SCF-2 mRNA, suggesting that this molecule may serve, next to c-Kit, as a prognostic marker for malignant melanoma.