Objective:To investigate the expression of anaplastic lymphoma kinase (ALK), tropomyosin receptor kinase (TRK), and recombinant C-Ros oncogene 1, receptor tyrosine kinase (ROS1) in Spitz tumors, and to analyze their associations with clinical and histopathological features of Spitz tumors.Methods:Clinical and histopathological characteristics, as well as follow-up data, were collected from patients with Spitz tumors at Department of Pathology, Hospital of Dermatology, Chinese Academy of Medical Sciences from January 2017 to August 2023, and retrospectively analyzed. Immunohistochemical staining for ALK, pan-TRK, and ROS1 was performed on skin tissues, and associations between the expression of these kinase proteins and clinicopathological features were analyzed.Results:A total of 57 patients with Spitz tumors were collected, including 36 females and 21 males. Immunohistochemical staining showed that 30 (52.6%) patients were positive for ALK, 4 (7.0%) were positive for ROS1, only 2 (3.5%) were positive for TRK, and 21 (36.8%) were negative for the three kinase proteins. Among the 30 ALK-positive patients, the median age was 9.5 years, 21 (70.0%) were females, and 15 (50.0%) presented with lesions on the face, which mainly manifested as papules or nodules; histologically, 29 (96.7%) patients had hypopigmented tumors with an exophytic growth pattern, and the tumor cells were mainly large and long spindle cells arranged in long cord-like, plexiform or fascicular patterns. Among the 4 ROS1-positive patients, there were 3 females and 1 male, presenting with exophytic papules or polyps; histologically, tumor cells were mostly arranged in small nests, without obvious clefts around cell nests. Two TRK-positive patients were both males aged 20 and 50 years respectively, and presented with brown and skin-colored flat papules, respectively; histologically, the tumors were located superficially with a flat base, and tumor cells spread in a pagetoid pattern in the epidermis, with some epithelioid cells and small cell nests. Among the 21 patients negative for the 3 kinase proteins, 9 were males and 12 were females, and they clinically presented with macules, papules and polypoid lesions; histologically, most tumors were located superficially, consisting of a mixture of epithelioid cells and spindle cells, with rare cytological atypia and mitotic figures, and 2 cases showed mild tissue structural and cellular atypia. Fifty-seven patients were followed up for 2 - 83.3 months, with a median follow-up of 19.2 months. Only 1 ALK-positive child experienced a recurrence, and no recurrence or lymph node metastasis was observed in the other cases.Conclusions:Among the three kinase proteins, ALK showed the highest positive rate in Spitz tumors in this study, while TRK- and ROS1-positive cases were sporadic. Histopathologically, ALK-positive Spitz tumor cells were mainly long spindle cells arranged in long cord-like or plexiform patterns, while TRK- and ROS1-positive Spitz tumors tended to have small cell nests. Both the kinase protein-positive and -negative Spitz tumors mostly had a good prognosis.

Objective:To investigate clinicopathological features and prognosis of transformed mycosis fungoides (TMF) .Methods:A retrospective analysis was performed on clinicopathological data collected from 24 patients with TMF, as well as on flow cytometry results of 16 peripheral blood samples obtained from 11 of the 24 patients, who visited Hospital of Dermatology, Chinese Academy of Medical Sciences between 2014 and 2020.Results:Among the 24 patients, 11 were males and 13 were females. Their average age at diagnosis of TMF was 50.0 years (range: 18 - 77 years), and patients with early-stage TMF (9 cases) and tumor-stage TMF (15 cases) were aged 44.8 and 52.6 years on average, respectively. The average time interval from diagnosis of MF to large cell transformation was 3.7 years, and 8 patients were diagnosed with TMF at the initial visit. Histopathologically, large cells infiltrated in a diffuse pattern in 20 cases, as well as in a multifocal pattern in 4, and the proportion of large cells in 7 cases was greater than 75%. Immunohistochemically, 18 patients showed positive staining for CD30, and the proportion of CD30-positive large cells was greater than 75% in 9; negative staining for CD30 was observed in 6. Flow cytometry of 16 peripheral blood samples showed the presence of cell subsets expressing clonal T cell receptor (TCR) -vβ in 2 of 4 patients with early-stage TMF and 10 of 12 with tumor-stage TMF, and tumor cells with higher forward scatter than normal lymphocytes were detected in 16 samples. During the follow-up, among the patients with early-stage TMF, 3 progressed to tumor-stage TMF 3.3 years on average after large cell transformation, 1 progressed to erythrodermic MF in stage IIIA, and the other 4 still showed an indolent course; among the patients with tumor-stage TMF, 1 progressed to stage-IV TMF, and 5 died 3.3 (1.5 - 6) years after large cell transformation.Conclusion:Large cell transformation may occur in patients with MF in any stage, some patients have poor prognosis, so close follow-up is needed for patients with TMF.

Objective: To analyze clinical and pathological features of papular elastorrhexis. Methods: Clinical data were collected from 22 patients with confirmed papular elastorrhexis in Hospital for Skin Diseases, Chinese Academy of Medical Sciences and Pekin Union Medical College from September 2006 to May 2018. Clinical manifestations, pathological findings and follow-up results were retrospectively analyzed. Results: The average age of onset of the 22 patients was 5.7 years (range: 1 - 10 years) , and the male to female ratio was 4.5∶1. The average duration from the occurrence of disease to the confirmation of diagnosis was 1.5 years, and no definite etiology was found. The patients had no itching or pain sensation. Skin lesions were soft, slightly elevated, well-circumscribed, round, oval or polygonal-shaped, white papules with diameters of 1 - 10 mm, and wrinkles appeared on the surface of the papule when the papule was pushed towards its center. Among the 22 patients, 16 (73%) presented with scattered lesions, 13 (59%) had less than 5 papules, and lesions were located in the trunk in 21 (95%) . Histopathological examination of skin lesions in 8 patients showed no obvious increase of collagen fibers in the superficial and middle dermis, which were normally arranged with slightly widened spaces between them. Elastic fiber staining showed that elastic fibers disappeared or were dissociated focally in the superficial and middle dermis. After confirmed diagnosis, the 22 patients received no treatment. In 18 patients, skin lesions did not continue to expand after onset, and no new skin lesions occurred. Skin lesions were slightly enlarged, but remained steady thereafter in 4 patients. Sixteen patients achieved partial remission. Conclusions Papular elastorrhexis is a rare skin disorder of elastic fibers that occurs predominantly during childhood and adolescence, and its diagnosis relies on clinical manifestations combined with histopathological findings. No special treatment is needed and the prognosis is good.

Objective To discuss the diagnosis and differential diagnosis of microcystic adnexal carcinoma (MAC).Methods Totally,10 patients with MAC were enrolled from Hospital for Skin Diseases,Chinese Academy of Medical Sciences from 2003 to 2017.Their clinical manifestations,histopathological and immunohistochemical features,treatment and prognosis were retrospectively analyzed.Results Of the 10 patients,3 were males and 7 were females.Their average age at the onset of MAC was 51.65 years.Skin lesions all occurred on the face,and on the upper lip in 6 cases.The lesions usually presented as solitary plaque or nodule,and ulceration occurred in 4 cases.Histopathologically,skin lesions consisted of epithelial cords with different numbers of keratinous cysts and tubular structures,and neural involvement occurred in 6 cases.However,mitotic figures were rare.Immunohistochemical staining showed epithelial cells and keratinous cysts stained positive for cytokeratin,as well as tubular structures and glandular cavities stained positive for carcinoembryonic antigen and epithelial membrane antigen.All the patients received surgical excision,and one patient experienced in situ recurrence 13 years later.No distant metastasis occurred in these patients.Conclusions MAC mainly presents as red plaques with occasional ulceration on the upper lip.Its definite diagnosis depends on characteristic histopathological changes in bidirectional differentiation into hair follicles and sweat glands,and immunohistochemical features are helpful to distinguish MAC from other adnexal tumors.

Objective To construct a recombinant lentiviral vector carrying the casitas B-lineage lymphoma (Cbl)-b short hairpin RNA (shRNA),and to evaluate its effect on the biological behavior of A375 melanoma cells in vitro.Methods Three specific shRNAs targeting Cbl-b gene and a negative control shRNA were designed and synthesized,and recombinant lentiviral vectors were constructed.A375 cells were divided into 5 groups to be transfected with 3 kinds of lentiviral vector expressing Cbl-b genespecific shRNAs (CBLB-shRNA-1 group,CBLB-shRNA-2 group and CBLB-shRNA-3 group),a lentiviral vector containing negative control shRNA (negative control group),and an empty vector (blank control group).Real-time fluorescence-based quantitative PCR and Western blot analysis were performed to determine the silencing efficiency at 72 hours after transfection.Cell counting kit-8 (CCK-8)assay was conducted to evaluate cellular proliferative activity at 24,48,72 and 96 hours after transfection,flow cytometry to detect cell apoptosis and cell cycle at 72 hours after transfection,and Transwell invasion assay to assess cellular invasive activity at 72 hours after transfection.Results Three recombinant lentiviral vectors containing Cbl-b shRNA were constructed successfully.As Western blot analysis revealed,the CBLB-shRNA-3 showed the highest silencing efficiency.CCK-8 assay indicated that the proliferative activity of A375 cells was significantly lower in the CBLB-shRNA-3 group than in the negative control group and blank control group at 72 and 96 hours after transfection(all P ＜ 0.01).Flow cytometry showed that the apoptosis rate of A375 cells was significantly higher in the CBLB-shRNA-3 group (22.73％ ± 6.58％) than in the negative control group (6.08％ ± 1.35％,P ＜ 0.01) and blank control group (6.34％ ± 1.07％,P ＜ 0.01).The CBLB-shRNA-3 group showed a significantly higher proportion of A375 cells at G1 phase,but a significantly lower proportion of A375 cells at S phase compared with the negative control group and blank control group(all P ＜ 0.01).Transwell assay showed that there were significant differences in the number of A375 cells crossing the artificial basement membrane (matrigel) at 72 hours after transfection among the negative control group,blank control group and CBLB-shRNA-3 group (76.60 ± 1.82,73.20 ± 3.83,19.60 ± 1.14,respectively;F =794.50,P ＜ 0.01).Conclusions A recombinant CBLB-shRNA-3-expressing lentiviral vector which can efficiently silence Cbl-b gene has been successfully constructed.It can inhibit the proliferation,cell cycle progression and invasive activity of A375 cells,but promote the apoptosis of A375 cells.

A 55-year-old male patient presented with plaques on the face for more than 20 years,and no immunodeficiency diseases were diagnosed.Skin examination showed large areas of pink plaques on the nose,bilateral cheeks and upper oral lips with slight desquamation,verrucous hyperplasia on the dorsal area of the nose,and a bean-sized verrucous protuberance on the tip of the nose.Histopathological examination of the skin lesions revealed pseudoepitheliomatous hyperplasia in the epidermis and hyphae-like structures in the stratum corneum.Moreover,there was diffuse infiltration of inflammatory cells in the dermis,which mainly included neutrophils,lymphocytes,histiocytes and multinucleated giant cells.Periodic acid-Schiff (PAS)-positive spore-like structures were observed in the multinucleated giant cells.Culture of the lesional tissues on Sabouraud dextrose agar (SDA) medium showed grey-brown villous colonies.Microculture on the potato dextrose agar (PDA) medium yielded dark septate hyphae and pycnidia filled with a large number of spores.Microsphaeropsis arundinis was identified by fungal molecular biological techniques.The patient was diagnosed with cutaneous phaeohyphomycosis caused by Microsphaeropsis arundinis.The patient was treated with CO2 laser for the removal of verrucous protuberance on the tip of the nose,and oral itraconazole capsules at a dose of 200 mg twice a day.After 3-month treatment,the skin lesions subsided and the drug was withdrew.During 6-month follow-up,no relapse occurred.

Objective To investigate clinical and pathological features of 6 cases of disabling pansclerotic morphea (DPM).Methods Clinical and pathological manifestations of and follow-up results in 6 patients,who were clinically and histopathologically diagnosed with DPM in the Department of Pathology,Hospital for Skin Diseases,Chinese Academy of Medical Sciences and Peking Union Medical College from 2007 to 2017,were retrospectively analyzed.Results Among the 6 patients,4 were male and 2 were female.The age of onset ranged from 3 to 10 years,with an average age of 6.5 years.The average duration from the occurrence to the confirmation of the diagnosis was 6.2 years (range,2-10 years).At all the lesional sites,skin atrophy,thining and tightness occurred,and the limbs became thin.Additionally,there were muscular atrophy and visible deep thick veins on the surface of the limbs.The contracture,deformity and dysfunction of the adjacent joints occurred in 4 cases,and the lower limbs were obviously shortened in 2 cases.Peripheral blood examination showed no increase of eosinophils or hypergammaglobulinemia.Imaging examination revealed smooth cortical bone and clear trabecular bone,and no osseous abnormality was observed.Histopathological examination of contracted skin lesions of the lower limbs revealed atrophic and thinned epidermis,hyperpigmentation in the basal layer,hyperplastic,thickened,hardened and partly homogenized collagen fibers in the middle to deep dermis,subcutaneous adipose tissue region and deep tissue of the skin.Conclusions DPM usually does not affect viscera,but often involves deep tissue of the limbs.Histopathologically,DPM is mainly characterized by obviously hyperplastic and hardened collagen fibers in the dermis and subcutaneous tissue.

Objective To analyze differentially expressed proteins in A375 melanoma cells before and after short hairpin RNA (shRNA)-mediated Cbl-b gene silencing.Methods The label-free quantitative proteomics approach was performed to identify differentially expressed proteins between A375 cells transfected with lentiviral vectors containing Cbl-b shRNA (Cbl-b shRNA group) and those with control lentiviral vectors (control group).Then,the properties of differentially expressed proteins were analyzed by gene ontology (GO) and Kyoto Encyclopedia of Genes and Genome (KEGG) enrichment analysis.Western blot analysis was conducted to determine the expression of differential proteins (EphA2 and GSK3β) and phosphorylated protein kinase (p-AKT) after shRNA-mediated Cbl-b gene silencing.Statistical analysis was carried out by t test of two independent-samples for comparison of protein expression abundance between the two groups with SPSS 23.0 software.Additionally,the results of GO and KEGG enrichment analysis were analyzed by Fisher's exact test.Results A total of 3 449 proteins were identified and quantified,and 74 of them were differentially expressed between the Cbl-b shRNA group and control group.Compared with the control group,52 proteins were up-regulated and 22 were down-regulated in the Cbl-b shRNA group.GO enrichment analysis of differential proteins revealed that the top five significantly enriched biological processes were integrin-mediated cell adhesion,single-organism metabolic process,regulation of integrin-mediated cell adhesion,regulation of protein-targeting mitochondria and nucleic acid metabolic process.The top five significantly enriched molecular functions included DNA binding,2-iron,2-sulfur cluster binding,signaling receptor activity,cadherin binding and cell adhesion molecule binding.The top five significantly enriched cell components included nucleosome,DNA packaging complex,photoreceptor connecting cilium,DNA-protein complex and extracellular region part.KEGG enrichment analysis demonstrated that the top five significantly enriched melanoma-related signaling pathways were folate biosynthesis,axon guidance,extracellular matrix-receptor interaction,adherens junction and Wnt signaling pathways.As Western blot analysis revealed,the Cbl-b shRNA group showed lower protein expression of EphA2 (0.369),but higher protein expression of GSK3β (3.524) compared with the control group (1),which were consistent with the results of proteomics analysis.Additionally,the protein expression of p-AKT was down-regulated in Cbl-b shRNA group (0.453) compared with the control group (1).Conclusion Cbl-b may be involved in the occurrence of melanoma through a variety of biological pathways,and the EphA2/PI3K/AKT signaling pathway may be one important pathway.

A 59?year?old female patient, who received bilateral lower limb amputation 39 years ago, presented with eczematoid changes in both lower limbs for over 20 years, and with chronic granuloma?like lesions complicated by verrucous hyperplasia for more than 10 years. There were large areas of infiltrative and proliferative lesions with exudation and peripheral erythema at the amputation sites in both knee joints. The lesions were hard with tenderness on palpation. Microscopic examination of lesional scales with 10%KOH showed negative results for fungi. However, three times of culture on the Sabouraud dextrose agar(SDA)medium all grew the same kind of fungus, and the front side and reverse side of its filamentous colony were white and orange yellow respectively. Microculture showed that linear hyaline conidiophores came out from lageniform mother cells with conidia ascending alongside. The conidia looked like dark brown eye lens, with an equatorial germ slit. Based on these findings, this fungus was identified as Arthrinium phaeospermum. Periodic acid?Schiff (PAS) staining showed scattered hyphae in the stratum corneum. The internal transcribe spacer(ITS)sequence of the isolated fungus showed 99%consistency with that of Arthrinium phaeospermum. The patient was diagnosed with cutaneous Arthrinium phaeospermum infection, and treated with oral itraconazole capsules 200 mg/d for 16 days. One month later, follow?up showed satisfactory outcomes.