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PubMed1988

Plasma 5-S-cysteinyldopa correlates with tumor size in melanoma-bearing mice.

A sensitive assay method employing high performance liquid chromatography with electrochemical detection (HPLC-ED) was used to compare 5-S-cysteinyldopa (CD) levels in plasma to tumor size in a murine melanoma model system. Plasma CD levels correlated with the sizes of primary tumor masses in mice, and the presence of metastatic tumors did not significantly affect the relationship. Elevated plasma CD levels appear to be directly related to tumor pigmentation: mice who had nonpigmented tumors induced by injections of amelanotic melanoma cells (NP) did not have elevated plasma CD levels. These studies indicate that plasma CD levels may serve as a marker for pigmented malignant melanomas and may be useful in following patients who are at high risk for these tumors.

Animals↗
PubMed1988

Urinary excretion of 5-S-cysteinyldopa in relation to skin type, UVB-induced erythema, and melanocyte proliferation in human skin.

5-S-Cysteinyldopa (5-S-CD) is found in all pigment-producing cells and is the major precursor of phaeomelanin. However, the melanocyte specificity of the compound has been questioned. In order to elucidate the origin of 5-S-CD, we have now systematically studied the relationship between the 5-S-CD excretion in urine and the size of the melanocyte organ, UV-induced melanocyte proliferation, skin type, and the erythemal reaction. The skin type had no influence on the basal excretion of 5-S-CD. There was no significant correlation between the basal 5-S-CD excretion and the size of the melanocyte organ; that is, the number of skin melanocytes and nevi. During the irradiation, subjects with skin type II developed a more pronounced erythema (p less than 0.01) and had a significantly higher 5-S-CD excretion than those with skin type III-IV (p less than 0.01). No correlation was found between 5-S-CD excretion and UV-induced melanocyte proliferation. The lack of correlation between the basal 5-S-CD excretion and skin type or number of melanocytes suggests that the basal 5-S-CD in urine is mainly of extra-melanocytic origin. Our findings favor the view that the increase in 5-S-CD excretion during UV irradiation is due to UV damage.

Adult↗
PubMed1982

Effect of DOPA-loading on glutathione-dependent 5-S-cysteinyldopa genesis in melanoma cells in vitro.

The effect of dopa, cysteine, and glutathione on 5-S-cysteinyldopa (5-S-CD) genesis in melanoma cells cultured in normal and tyrosine- and cysteine-free media has been studied. In normal media only melanotic melanoma cells have been found to secrete 5-S-CD into the medium. In the presence of dopa and cysteine, both, media incubated with and without cells have been found to produce 5-S-CD. In the presence of dopa and glutathione, however, cell-free media did not show the presence of 5-S-CD. In contrast melanoma cell-cultured media has been found to contain large quantities of this amino acid. The optimum condition for maximum production of 5-S-CD via glutathione-dependent pathway has been found to be at the dopa concentration of 10(-5) M when glutathione is present at the concentration of 10(-5) M in the culture medium. Thus dopa concentration with regards to glutathione is 1:1 on the molar basis which is twice the dopa concentration required in in vitro noncellular tyrosinase system. It is suggested that higher dopa requirement in our melanoma cell culture system reflects the co-existence of eu- and pheomelanin synthesis taking place according to their genetically predetermined proportions.

Animals↗
PubMed1983

Characterization of structural properties for morphologic differentiation of melanosomes. III. free and protein-bound dopa and 5-S-cysteinyldopa in B16 and Harding-Passey melanomas.

This study analyzed the free and protein-bound forms of dopa, 5-S-cysteinyldopa (5-S-CD), and 5-S-glutathionedopa (5-S-GD) in B16 and Harding-Passey (HP) mouse melanomas to investigate the role of these catechols for melanogenesis and melanosome morphogenesis, inasmuch as these tumors produce melanosomes different in color and ultrastructure, i.e., eumelanosome type in B16 and pheomelanosome type in HP. Between B16 and HP mouse melanomas, however, we found (a) no significant difference in the level of free dopa and 5-S-CD in melanosomes and tumors, although the levels of these catechols reflected well the type of melanogenesis in control hair of normal mice, (b) a significant difference in free 5-S-GD level, which might, in part, reflect the observed difference in melanogenesis, and (c) no apparent difference in the level of bound dopa and 5-S-CD in either melanosomes or tumors. Thus, the striking difference in the color of melanosomes between B16 and HP melanomas seems to be related primarily to the content--not the type--of melanin pigments.

Animals↗
PubMed1983

gamma-Glutamyl transpeptidase, tyrosinase, and 5-S-cysteinyldopa production in melanoma cells.

The distribution of gamma-glutamyl transpeptidase (gamma-GTP), tyrosinase, and 5-S-cysteinyldopa (5-S-CD) within melanoma cells has been studied in vitro as well as in vivo. Sodium periodate treatment of intact B-16 melanoma cells has been found to inhibit gamma-GTP present as an ectoenzyme. However, these periodate-treated cells in the presence of 10(-5) M dopa and glutathione have been found to continue to secrete large quantities of 5-S-CD in their medium. The large-granule fraction of Greene's melanotic melanoma contains substantial amounts of both tyrosinase and gamma-GTP. However, further separation of the large-granule fraction into sub-fractions indicates that tyrosinase and gamma-GTP seem to co-exist with premelanosome. It is suggested that glutathione-dependent t-S-CD genesis proceeds within premelanosomes through the formation of glutathione-dopa. The excess of glutathione-dopa and 5-S-CD, unutilized for pheomelanin formation overglow into the cytoplasm.

Animals↗
PubMed1990

Pedunculated pigmented eccrine poroma of the scalp with increased urinary excretion of 5-S-cysteinyldopa.

We describe a 52-year-old man with a pedunculated pigmented eccrine poroma mimicking a nodular malignant melanoma in the occipital region. The tumor was once resected but soon recurred. Histologically, the tumor mass extended from the epidermis downwards into the dermis and contained melanin granules in some areas. The tumor cells were uniformly cuboidal in appearance and had round, deeply basophilic nuclei. Initially, the urinary excretion level of 5-S-cysteinyldopa (5-S-CD) was high, but, after resection of the tumor, the level of 5-S-CD returned to normal.

Adenoma, Sweat Gland↗
PubMed1992

Serum 5-S-cysteinyldopa (5-S-CD) as a marker of melanoma progression.

We previously reported that serum 5-S-cysteinyldopa (5-S-CD) tended to elevate earlier and reflect melanoma progression better than urinary 5-S-CD. In patients without metastatic melanomas, serum concentration and urinary excretion of 5-S-CD and 6-hydroxy-5-methoxy-indole-2-carboxylic acid (6H5MI2C) were within the upper limits of normal controls. In this report, we presented more precisely the changes in these melanin-related markers and clinical courses of four melanoma patients. Serum and 24-hour urine samples were serially collected and assayed every 1 to 4 months. Three of them developed stage IV malignant melanomas and died of metastatic disease. 6H5MI2C in serum and urine did not reflect the progression of disease. Among the 4 parameters considered, 5-S-CD in serum appeared to be the best biochemical marker for melanoma progression. Serum 5-S-CD over the upper limit of 10 nmol/L was suggested as a serious sign of the progression of melanoma.

Aged↗
PubMed1996

Serum concentration of 5-S-cysteinyldopa in pediatric patients with giant pigmented nevi.

The serum concentrations of 5-S-cysteinyldopa (5-S-CD) in pediatric patients with giant pigmented nevi (GPN) were investigated and compared with those of pediatric patients with small- or medium-sized congenital nevi (CN), or non-melanocytic benign skin tumor (control group). Serum 5-S-CD levels in the GPN group (N = 21), particularly in patients less than 5 years old, were significantly higher (highest concentration 38.4, mean +/- S.D. 16.6 +/- 9.4 nmol/L) than those in the CN (N = 22) or control groups (N = 26). Serum 5-S-CD levels in the CN group were not significantly different from those in the control group. There was a significant correlation between the serum 5-S-CD level and size (surface area) of the GNP. There was a significant inverse correlation between the serum 5-S-CD level and age in the CN and control groups, but not in the GPN group. Serum 5-S-CD levels were transiently elevated immediately after treatment of patients with GPN with a combination of skin abrasion and cryotherapy with solid carbon dioxide. These results suggest that serum 5-S-CD levels in the GPN group reflected the 5-S-CD derived from GPN, particularly in patients less than 5 years old. This indicates that melanogenesis may be accelerated in infant patients in the GPN group.

Adolescent↗
PubMed1988

Plasma 5-S-cysteinyldopa as an index of melanogenesis.

Plasma 5-S-cysteinyldopa (5-S-CD) concentration measured in healthy volunteers in Edinburgh, Scotland (latitude 56 degrees N) showed only minor changes during the day. However, when measurements were performed over a 12-month period a significant rise in 5-S-CD concentration was found. Skin pigmentation and hair colour were not related to plasma 5-S-CD levels. Patients with psoriasis treated with ultraviolet-B or photochemotherapy (PUVA) developed an almost two fold increase in their plasma 5-S-CD level within the first five treatments, before pigmentation developed, subsequent increments of up to four times the pretreatment level being found in the PUVA group. Dithranol treatment caused an increase in plasma 5-S-CD in some psoriatic patients, suggesting a possible association between skin erythema and elevated 5-S-CD levels. The value of plasma 5-S-CD in the follow-up of patients with malignant melanoma does not seem to be invalidated by unavoidable exposure of the subjects to sunlight in a temperate climate such as that of South East Scotland.

Adult↗
PubMed1995

Seasonal variation in serum concentration of 5-S-cysteinyldopa and 6-hydroxy-5-methoxyindole-2-carboxylic acid in healthy Japanese.

Serum concentrations of 5-S-cysteinyldopa (5-S-CD) and 6-hydroxy-5-methoxyindole-2-carboxylic acid (6H5MI2C) have been used as biochemical markers of melanoma progression. We examined the effect of solar radiation on serum levels of 5-S-CD and 6H5MI2C in 10 healthy Japanese by measuring these markers every month during a period of 2 years. 5-S-CD levels were higher in early summer and lower in early winter. The difference in the average levels was approximately twofold, but among the 240 samples, no individual values exceeded the upper limit of normal value, 10 nmol/L. A significant correlation (P < 0.02) was observed between 5-S-CD level and solar radiation. 6H5MI2C levels showed a smaller variation than 5-S-CD. No correlation was observed between 6H5MI2C level and solar radiation. This study showed that serum 5-S-CD and 6H5MI2C in healthy Japanese did not exceed the upper limit of normal values even in sunny season.

Cysteinyldopa↗
PubMed1994

Photochemistry of 5-S-cysteinyldopa.

The photochemical behavior of 5-S-cysteinyldopa (5-S-CD), a colorless product of melanocyte metabolism, was investigated in neutral phosphate buffer with biologically relevant UV radiation. Exposure of 5-S-CD to pyrex-filtered UV light (wavelengths > 320 nm) was found to induce an oxygen-dependent reaction, leading to, besides abundant polymeric materials, the benzothiazine derivatives I and II (two diastereoisomers). Superoxide dismutase exerted a small inhibitory effect on 5-S-CD consumption, whereas other active oxygen scavengers had no effect on the reaction course. Addition of glutathione as a hydrogen donor completely suppressed the reaction. With UVB light (wavelength range 280-320 nm) photolysis of 5-S-CD proceeded mainly with formation of 3,4-dihydroxyphenylalanine, arising presumably by photohomolytic cleavage of the S-CH2 bond followed by desulfuration. These results are of interest in relation to the high susceptibility of fair-complexioned individuals to actinic damage and skin cancer.

Cysteinyldopa↗
PubMed2003

Neurocutaneous melanosis associated with malignant leptomeningeal melanoma in an adult: clinical significance of 5-S-cysteinyldopa in the cerebrospinal fluid---case report.

A 35-year-old male presented with a variant of neurocutaneous melanosis with leptomeningeal malignant melanoma. He had three pigmented nevi from birth. He suffered diplopia followed by headache. T1-weighted magnetic resonance (MR) imaging revealed hydrocephalus and a small linear hyperintense lesion in the right frontal cortex. Several parts of the cortical sulci and the brain surface were slightly enhanced by gadolinium. Ventriculoperitoneal shunting was performed and extensive pigmented leptomeninges were recognized. Open biopsy established the diagnosis of leptomeningeal malignant melanoma. Combined chemoimmunotherapy was repeated every other month with monitoring of the 5-S-cysteinyldopa (5-S-CD) level in the cerebrospinal fluid (CSF). The 5-S-CD level decreased after each treatment, but the basal level steadily increased prior to the next treatment. Two years after the onset, he showed paraplegia caused by an extramedullary mass at the T-6 level. MR imaging showed that melanoma had involved the entire subarachnoid space including the whole spine. He underwent emergent removal of the spinal tumor and showed transient marked improvement. Further intensive chemotherapy was given. However, he died 31 months after the onset of massive proliferation of intracranial leptomeningeal melanoma. Measurement of CSF 5-S-CD levels is valuable for evaluating the therapeutic efficacy and for monitoring the progression of melanoma.

Adult↗
PubMed1997

Evaluation of the clinical usefulness of measuring urinary excretion of 5-S-cysteinyldopa in melanoma: ten years' experience of 50 patients.

The urinary excretion of 5-S-cysteinyldopa (5-S-CD) is known to be increased in certain patients with melanoma. To evaluate its diagnostic and prognostic utility, we measured the urinary excretion of 5-S-CD on at least three different occasions in 50 patients with melanoma. No significant increase was found in 26 patients without metastases, in 10 patients with regional lymph node metastasis and 2 patients with amelanotic melanoma. However, all the 12 patients with distant metastases demonstrated a significant increase. The patients with 5-S-CD > 1,000 micrograms/day survived for a mean of 8.1 +/- 5.6 months, while those with 5-S-CD > 10,000 micrograms/day survived for 3.5 +/- 3.7 months. All the 4 patients with a maximum excretion of 5-S-CD > 40,000 micrograms/day had multiple liver metastases. In conclusion, while data on the urinary excretion of 5-S-CD was not useful in the detection of early regional lymph node metastases, its increase indicated the presence of distant metastases and also provided prognostic information.

Adult↗
PubMed2002

Clinical significance of 5-S-cysteinyldopa monitoring in patients with malignant melanoma.

5-S-cysteinyldopa is a precursor of melanin. Its serum and urinary level can reflect melanoma progression. In this study the concentration changes of 5-S-CD in melanomas of all stages were examined, and patients were monitored during and after treatment. Serum samples were taken from 479 melanoma patients with different Stages on 1924 occasions, from June 1996 to December 2000. Levels of 5-S-CD were determined by HPLC. The mean/median value of 5-S-CD in the Stage I-II-III patients and in the control group ranged around the normal level. Significant difference was found between Stage III and Stage IV as well as between patients with no evidence of disease and patients with tumor burden. In Stage IV 69.7% sensitivity, 61.5% specificity and 79.3% positive predictive value were evaluated. The survival of patients with normal 5-S-CD level (n=235) differed significantly from cases having elevated marker concentration (n=244). One hundred eighty cases were regularly monitored on 1210 occasions. Recurrence development was noticed in 57 patients. In 24.6% of these patients suffering from any type of disease progression the increasing marker level preceded the detection of metastasis by conventional methods. Serum 5-S-CD in Stage IV is sensitive enough to detect distant metastasis, and its predictive value has a great importance. It is a reliable marker for monitoring the clinical course in malignant melanoma.

Biomarkers, Tumor↗
PubMed1990

[Eumelanin and pheomelanin contents in hairs of healthy Japanese and patients with oculocutaneous albinism, and 5-S-cysteinyldopa and 5-hydroxy-6-methoxyindole-2-carboxylic acid levels in urine of oculocutaneous albinism].

The contents of eumelanin and pheomelanin in the scalp hairs of 4 Japanese patients with total albinism (3 tyrosinase-positive and one negative) and 100 healthy Japanese were measured by the melanin microquantitation method of Ito and Fujita. The urinary 5-S-Cysteinyldopa (5-S-CD) and 5-Hydroxy-6-Methoxyindole-2-Carboxylic acid (5H6MI2C) contents in the 4 albino subjects were also determined. Our findings included that (1) Regardless of ge, black hairs of all the healthy subjects contained phemelanin at a level of about 5% of the total melanin contents. The hair color of the 3 tyrosinase-positive subjects was pale-yellow, and their hairs contained only pheomelanin. The hair color of the one tyrosinase-negative subject was white, and neither eumalanin nor pheomelanin could be detected. (2) Urinary 5H6M12C, an indicator of eumelanin production in the body, could not be detected in either the tyrosinase-positive or tyrosinase-negative subjects, while the urinary 5-S-CD content of the tyrosinase-negative subject was much lower than that of the tyrosinase-positive subjects. These results suggested that the yellow hair color of patients with tyrosinase-positive albinism is attributable to the production of only pheomelanin and that the urinary 5-S-CD content does not necessarily reflect the ability to produce melanin.

Adolescent↗
PubMed1985

Urinary excretion of 5-S-cysteinyldopa and 6-hydroxy-5-methoxyindole-2-carboxylic acid: differences between pigmented and albino mice.

Urinary excretion of the phaeomelanin precursor 5-S-cysteinyldopa (5-S-CD) and the eumelanin metabolite 6-hydroxy-5-methoxyindole-2-carboxylic acid (6H5MI-2-C) was studied in black and albino mice. The urinary concentration of 5-S-CD was 31.7 ng/ml in black and 16.1 ng/ml in albino mice. The concentration of 6H5MI-2-C was 21.0 ng/ml in the urine of black mice. The compound could not be demonstrated in the urine of albino mice.

Albinism↗
PubMed1987

Seasonal variation in urinary excretion of 5-S-cysteinyldopa in healthy Japanese.

The urinary excretion of 5-S-cysteinyldopa was examined in 10 healthy Japanese subjects once a month during a period of one year. The mean values were highest in August (296 micrograms/day) and lowest in February (141 micrograms/day). Individual variations were so great that only a weak difference was observed (p less than 0.05).

Adolescent↗
PubMed1989

[Biochemical diagnoses of malignant melanomas with determinations of 5-S-cysteinyldopa in lesions].

To develop a biochemical diagnosis for malignant melanomas, 5-S-cysteinyldopa in the tissues of malignant melanomas and other pigmented tumors were quantitatively analysed. The mean 5-S-CD value from primary melanotic melanoma lesions was 202.4 ng/mg (80.6-821.4) and those of metastatic melanoma lesions was 214.0 ng/mg (96.2-520.0). There was no significant differences in these 5-S-CD values between the types of primary lesions. On the other hand, the 5-S-CD values from pigmented tumors other than melanomas, such as Spitz nevus, dysplastic nevus, pigmented basal cell epithelioma, and melanoepithelioma Bloch II were less than 55 ng/mg. From these results it is thought that pigmented tumors can be diagnosed as malignant melanomas, if the 5-S-CD values in the tissues are over 100 ng/mg. The mean 5-S-CD values of pigmented macules of SSM was 734.5 ng/mg (320.0-1666.3) and those of ALM was 1.8 ng/mg (0.7-3.6). These data suggest that the biochemical diagnoses of SSM in situ can be based on 5-S-CD values, the diagnoses of ALM in situ can not.

Adult↗