Hypopigmented Mycosis Fungoides: A Clinicopathological Review of 32 Patients.

Background: Hypopigmented mycosis fungoides (hMF) is gradually acknowledged by more dermatologists, yet a consensus regarding its characteristics is not reached. The profile of Chinese hMF patients has not been deeply reviewed previously. Our research may contribute to the understanding of hMF, especially the Chinese patients with Fitzpatrick phototypes of III and IV. Aim: To have a better understanding of hMF in terms of clinical, histopathological and immunohistochemical features in the Chinese population and to determine if there are differences between the Chinese population and other ethnic groups. Methods: We made a retrospective analysis of clinical, histopathological and immunohistochemical features of 32 hMF patients in our hospital from 2010 to 2020. These features were then summarized and compared with previous reports. Results: All patients belonged to Fitzpatrick phototypes of III or IV. Twenty-one male (65.63%) patients and 11 female (34.37%) patients were analyzed, and the male to female ratio was 1.9:1. The age at diagnosis of patients ranged from 4 to 39 years, and the average age at diagnosis of these patients was 18 years, the median age was 16.5. Back was the most frequent site (34.37%). The clinical and histological results of lesions had no distinctive points. Immunohistochemically, among these 32 patients, there were 30 patients whose information was complete, there was 19 patients (63.33%) who were CD8 positive lymphocytes predominance, 9 patients (30%) had CD8 and CD4 positive lymphocyte mixed infiltration, and other 2 patients (6.67%) had CD4 positive lymphocytes predominance. Partial loss of CD7 was only observed in 1 patient (3.33%). Nearly all patients adopted topical nitrogen mustard and topical steroid and most of them had an excellent prognosis. Conclusion: The clinical profiles of hMF in Chinese population shared differences with other ethnic groups, but its histopathological, immunohistochemical results and prognosis condition were resembled with other previous reports. Hence, more patients were needed to find the characteristics of hMF.

Expression of Rho GTPases family in melanoma cells and its influence on cytoskeleton and migration.

Rho GTPases family members influenced the filopodia, lamellipodia, stress fiber and adhesion plaque of melanoma cells through regulating cytoskeleton recombination. The role of Rho GTPases family in the migration and invasion of melanoma and its molecular mechanism were explored. The morphological difference between three types of melanoma cells (M14, A375 and MV3) and human melanocyte (MC) was observed by the Hoffman microscope. Cells were stained by phalloidin labeled by rhodamine. The differences between 4 types of cells in filopodia, lamellipodia, stress fiber and adhesion plaque (microfilament is the main constituent) were observed under the super-high resolution microscope. The migration ability of 4 types of cells was detected by Transwell migration assay. QPCR was used to detect the mRNA transcription level of Rho GTPases family. WB was adopted to detect the expression of RhoD and DIAPH2 proteins. There were significant differences in filopodia, lamellipodia, stress fiber and adhesion plaque between MC and 3 types of melanoma cells (M14, A375 and MV3). MC did not have stress fiber or adhesion plaque, while M14, A375 and MV3 had stress fiber and adhesion plaque. All 4 types of cells had thin and short filopodia. MV3 had fewer but thicker stress fibers than the latter two. Transwell migration test indicated the followings: M14 and A375 had a similar high migration rate; the migration rate of MV3 was slightly low; MC did not have the ability of transmembrane migration. QPCR results of Rho GTPases family in 4 types of cells showed the change corresponding to immunofluorescence. WB results showed that RhoD was barely expressed in M14, A375 or MV3. DIAPH2, the downstream effector molecule of RhoD, had the corresponding change. Rho GTPases influences the migration and invasion of melanoma cells through regulating filopodia, lamellipodia, stress fiber and adhesion plaque (microfilament is the main constituent).

[Quantitative determination of podophyllotoxin in dermal and blood microdialysis samples of rats by liquid chromatography-tandem mass spectrometry].

OBJECTIVE: To develop and validate a sensitive method for quantitative analysis of podophyllotoxin in blood and dermal microdialysis samples of rats based on liquid chromatography-tandem mass spectrometry (UFLC-MS-MS). METHODS: The microdialysis samples were prepared by liquid-liquid extraction using ethyl acetate with etoposide as the internal standard (IS). Podophyllotoxin was separated with an Agilent ZORBAX XDB-C18 column (2.1 mmx50 mm, 3.5 microm). The mobile phase consisted of acetonitrile: 10 mmol/L ammonium acetate (40:60, V/V) at a flow rate of 0.3 ml/min and the analysis was performed at the ambient temperature. The UFLC-MS/MS system was operated in the mode of multiple reaction monitoring using the electrospray ionization technique in positive mode. RESULTS: Podophyllotoxin and etoposide responses were optimized at the transitions m/z 432.7-->397.3 and 589.5-->229.5, respectively. Calibration curves were linear over the range 2.0-1000 ng/ml. The lowest limits of quantification and detection values were 2.0 ng/ml and 0.7 ng/ml, respectively. The inter- and intra-day precision and accuracy were both less than 15%. CONCLUSION: This selective and sensitive method can be used to quantity podophyllotoxin in the blood and dermal microdialysates of rats.