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- Swanson LW, Sanchez-Watts G, Watts AG. Comparison of melanin-concentrating hormone and hypocretin/orexin mRNA expression patterns in a new parceling scheme of the lateral hypothalamic zone. Neurosci Lett. 387(2):80- 4, 2005. - Takahashi A, Kawauchi H. Evolution of melanocortin systems in fish. Gen Comp Endocrinol. 2005 Nov 10. - Tobin DJ, Kauser S. Hair melanocytes as neuro-endocrine sensors-Pigments for our imagination. Mol Cell Endocrinol. 243(1-2):1-11, 2005. Epub 2005 Oct 11. 1421
4.. Phottobiiollogy (Dr. N. Smit) In a letter to the editor Hacker et al describe the various mouse models and genetic backgrounds that are capable of producing UVR induced melanoma. They used a brown mouse strain with a melanocyte-specific Hras mutant (G12V) transgene (TPras). The animals received a neonatal regimen of UVR (with Philips FS40 UVB lamps) and obtained cutaneous melanoma tumors with high penetrance (57%) whereas previous chronic exposure regimen did not result in development of tumors. There was a marked reduction in pigmentation of the neonatal TPras animals as compared to the adult highly pigmented TPras animals. The UV induced melanoma formation did not always involve loss of Ink4A or Arf and the authors concluded that NRAS and BRAF mutations co-operate with solar UVR in development of melanoma. Induction of melanoma in the different mouse models strongly depends on the genetic background and also on the pigmentation characteristics. Chintala et al describe the subtle gray (sut) mouse where a mutation in the Slc7a11 gene is responsible for a low rate of extracellular cystine transport. Next to influences on pheomelanin pigmentation the reduced cystine transport is also critical for cell proliferation and protection from oxidative stress. The sut mice are considered as a model for oxidative stress-related diseases. It could be possible that a strong uptake of cystine by pheomelanogenesis may also reflect such a situation in some cases of melanocytes with RedHairColour phenotype. The paper by Corre et al reviews the role of the upstream stimulating factors (USF). In melanocytes USF-1 has been implicated to play an important role in the (UV)-activation of genes associated with pigmentation. Next to the role of USF-1 in the tanning response the place of USF-transcription factors in various regulatory networks is outlined in the paper. In the introduction of the paper by Marrot et al also the induction of melanoma tumors in mouse models (see above) is mentioned and the lack of a clear "UV signature" in the melanoma cells is discussed. Various stress factors were already implicated in gene expression studies performed by others after UVA irradiation of melanocytes. In the study by Marrot induction of important cell cycling regulating proteins such as p21 and GADD45 were shown at various time points after different doses of solar simulated radiation (both UVB and UVA). A 10 min UV irradiation induced both p21 and GADD45 within 4 hrs. Twenty min irradiation resulted in a more prominent induction of GADD45 lasting up to 15 hrs whereas the p21 response was delayed (24 hrs). Effects on cell cycle and accumulation of cells in G2-M phase were shown by FACS analysis that may correlate well with the GADD45 induction. Another new finding is the early induction of heme oxygenase 1(HO-1) by SSR and UVA in the melanocytes. Interestingly this HO-1 induction was increased when melanogenesis in the cells was stimulated. This may be another important indication that intracellular melanin plays a role in UV induced stress. The paper by Curtin et al offers an interesting contribution to the discussion about melanoma, the role of UV-B or UV-A induced damage, pigmentation and "stress" cell cycling regulatory pathways. As was shown earlier in one of the refs (16 Maldonado et al JNCI 2003) BRAF and N-RAS mutations on skin without chronic sun-induced damage (non-CSD) occurred in 81% of melanomas. In other types (CSD, acral and mucosal) of melanoma a majority had mutations in neither gene. Among the four groups significant differences in copy numbers of CDKN2A, PTEN, CDK4 and CCND1 were demonstrated. Changes in the MAP-Kinase and PI3Kinase pathways are considered to be of major importance in melanoma. Next to BRAF and N-RAS, CDK4 and CCND1 could act as independent oncogenes promoting proliferation while loss of PTEN may influence survival via the PI3Kinase pathway. Reference List - Alexandre M, Kisner R, Sharpe I. Does skin cancer discriminate? What role does skin pigment play in the development of melanoma skin cancer? Ethn.Dis. 15:S4-66, 2005. 1422
Page 1 and 2: N° 53 Dec 2005 E S P C R B U L L E
Page 3 and 4: paper on photosensitization and lys
Page 5 and 6: The Pigment Cell Community knows Dr
Page 7 and 8: such scientists and recruit them to
Page 9 and 10: Optical spectra of melanin films ex
Page 11 and 12: 2.. Biiollogy off piigmentt celllls
Page 13 and 14: - Akhtar S, Gavalas NG, Gawkrodger
Page 15 and 16: Endothelin-1 indices CXCL1 and CXCL
Page 17 and 18: - Kym PR, Iyengar R, Souers AJ, Lyn
Page 19: Melanin-concentrating hormone induc
Page 23 and 24: - Grant WB, Garland CF, Holick MF.
Page 25 and 26: 5.. Neuromellaniins (Prof. M. d'Isc
Page 27 and 28: eye/ear pigmentation and suggest ve
Page 29 and 30: 6.. Genettiics,, mollecullar and de
Page 31 and 32: - Jungers KA, Le Goff C, Somerville
Page 33 and 34: Molecular dissection of mesenchymal
Page 35 and 36: 7.. Tyrosiinase,, TRPs,, otther enz
Page 37 and 38: The development of effective skin-l
Page 39 and 40: of PPO is practically null at low c
Page 41 and 42: Generation of superoxide anion and
Page 43 and 44: displayed a pattern, which correspo
Page 45 and 46: - Ohguchi K, Banno Y, Nakagawa Y, A
Page 47 and 48: substrates rather than catechol-typ
Page 49 and 50: 8.. Mellanosomes (Prof. J. Borovans
Page 51 and 52: transporting a melanosome increased
Page 53 and 54: 2006 36 th Annual ESDR Meeting Sept
Page 55 and 56: 2007 21 th Annual Meeting of the Ja
Page 57 and 58: Outgoings 9/2004-9/2005 IFPCS subsc
Page 59 and 60: Election of ESPCR Officers, 2006-20
Page 61: Mayuko KUMASAKA Developmental Genet

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