Gasdermin A Is Required for Epidermal Cornification during Skin Barrier Regeneration and in an Atopic Dermatitis-Like Model.

Atopic dermatitis is featured with impaired skin barrier. The stratum corneum and the intercellular tight junctions constitute the permeability barrier, which is essential to protect water loss in the host and prevent pathogen entry. The epidermal barrier is constantly renewed by differentiating keratinocytes through cornification, during which autophagy contributes to elimination of organelles and nucleus. The human GSDMA and its mouse homologs Gsdma1-3 are expressed in the suprabasal epidermis. Although a pyroptotic role of GSDMA/Gsdma1 in host defense against Streptococcus pyogenes has been reported, the physiological function of Gsdma1/a2/a3 in epidermal homeostasis remains elusive. Here, through repeated epidermal barrier disruption, we found that tight junction formation and stratum corneum maturation were defective in the Gsdma1/a3-deficient epidermis. Using comparative gene profiling analysis, mitochondrial respiration measurement, and in vivo tracing of mitophagy, our data indicate that Gsdma1/a3 activation leads to mitochondrial dysfunction and subsequently facilitates mitochondrial turnover and epidermal cornification. In calcipotriol (MC903)-induced atopic dermatitis-like animal model, we showed that Gsdma1/a3-deficiency selectively enhanced the T helper type 2 response. Remarkably, the GSDMA expression is reduced in the epidermis of patients with atopic dermatitis compared with that of normal individuals. Gsdma1/a3-deficiency might be involved in atopic dermatitis pathogenesis, likely through GSDMA-mediated epidermal differentiation and cornification.

Limited effect of reducing pulmonary tuberculosis incidence amid mandatory facial masking for COVID-19.

Although the incidence and mortality rates associated with tuberculosis (TB) have been decreasing in many countries, TB remains a major public health concern. Obligatory facial masking and reduced health-care capacity because of COVID-19 may substantially influence TB transmission and care. The Global Tuberculosis Report 2021 published by the World Health Organization indicated a TB rebound at the end of 2020, which coincided with the COVID-19 pandemic. We explored this rebound phenomenon in Taiwan by investigating whether TB incidence and mortality are affected by COVID-19 because of their common route of transmission. In addition, we investigated whether the incidence of TB varies across regions with different incidences of COVID-19. Data (2010-2021) regarding annual new cases of TB and multidrug-resistant TB were collected from the Taiwan Centers for Disease Control. TB incidence and mortality were assessed in Taiwan's seven administrative regions. Over the last decade, TB incidence decreased continually, even during 2020 and 2021, the years coinciding with the COVID-19 pandemic. Notably, TB incidence remained high in regions with low COVID-19 incidence. However, the overall decreasing trends of TB incidence and mortality remained unchanged during the pandemic. Facial masking and social distancing may prevent COVID-19 transmission but exhibit limited efficacy in reducing TB transmission. Thus, during health-related policymaking, policymakers must consider TB rebound, even in the post-COVID-19 era.

The pathophysiology and current treatments for the subcutaneous panniculitis-like T cell lymphoma: An updated review.

Subcutaneous panniculitis-like T cell lymphoma (SPTCL) is a rare cutaneous T cell lymphoma, which is indolent in nature but could claim life if not correctly diagnosed and promptly treated. SPTCL is usually presented clinically as painless subcutaneous and erythematous nodules over the trunk or extremities. Active clinical vigilance for these subcutaneous nodules or panniculitis-like lesions is warranted. A biopsy must be performed in order to make a correct diagnosis. Positron emission tomography scan is utilized for disease staging and treatment follow-up. Due to the rarity of this lymphoma, a standard treatment protocol is not established yet. However, most cases of SPTCL could be treated well under immunosuppressive or polychemotherapeutic drugs except in cases with hemophagocytic syndrome. Hematopoietic stem cell transplantation may be used in refractory or relapse cases. In this review, we presented a case of SPTCL with long-term complete remission. Meanwhile, since most clinical evidences and experiences of SPTCL are based mostly on case reports or small case series, and the understanding of the SPTCL pathophysiology is limited, we reviewed and updated the pathophysiology and treatments of SPTCL.

IL-33 Enhances ACE2 Expression on Epidermal Keratinocytes in Atopic Dermatitis: A Plausible Issue for SARS-CoV-2 Transmission in Inflamed Atopic Skin.

BACKGROUND: Interleukin-33 (IL-33) is an important cytokine in the pathophysiology of atopic dermatitis (AD) and in the progression of COVID-19. Angiotensin converting enzyme 2 (ACE2), the entry receptor for SARS-CoV-2, is expressed in epidermal keratinocytes. Whether IL-33 could regulate the expression of ACE2 mechanistically in keratinocytes warrants investigation. OBJECTIVE: We questioned whether the ACE2 expression is increased in AD skin. We also questioned whether ACE2 is expressed in keratinocytes; if so, would its expression be enhanced mechanistically by IL-33. METHODS: We measured and compared the expression of ACE2 in skin from patients with AD, patients with psoriasis, and healthy controls using immunohistochemistry. Flow cytometry, immunofluorescent exam, and quantitative RT-PCR were used for measuring the ACE2 expression in cultured keratinocytes treated with IL-33 and IL-17. Blocking antibodies were utilized to study the intracellular signaling pathways governing the ACE2 expression using cytokines. RESULTS: The results showed that the ACE2 expression is increased in AD compared with that in healthy skin and psoriasis. In primary epidermal keratinocytes, ACE2 is constitutively expressed. IL-33 induces a time-dependent increase in ACE2 expression in cultured keratinocytes through quantitative PCR, flow cytometry, and immunofluorescent examinations. Furthermore, pretreatment of an ERK inhibitor, but not a STAT3 inhibitor, eliminated the increases in ACE2 by IL-33 in keratinocytes, indicating that IL-33 enhances ACE2 expression through ERK on epidermal keratinocytes. CONCLUSION: This is the first study to reveal that IL-33 enhances ACE2 expression on keratinocytes via ERK. Although further mechanistic studies are required, the increased ACE2 expression in IL-33 might have a biological implication on the transmission of SARS-CoV-2 in patients with AD.

Taiwanese dermatological association consensus for the definition, classification, diagnosis, and management of urticaria: A 2021 update.

Urticaria is a prevalent disease with substantial physical, psychological, and economic impacts. With the advent of understandings of the disease and the emerging evidence of treatments, the international guidelines for treating urticaria have been updated in recent years. In order to update the 2014 edition of the Taiwanese Dermatological Association (TDA) consensus of urticaria, a total of 17 dermatologists with extensive experience in urticaria management were invited to and attended the TDA consensus meetings. All the specific aspects of the content were approved by at least 75% of the experts in attendance. Comparing to the former edition, several substantial modifications were made. For diagnosis, D-dimer was added as the recommended routine test in patients with chronic spontaneous urticaria. For pharmacological management, treatment suggestions were simplified. The approved-dosed, the up-dosed second-generation antihistamines, omalizumab, and cyclosporine were listed as the first-line to the fourth-line treatment, respectively. In addition, the management for patients of special considerations, such as the elderly, children, and pregnant women, were all discussed and mentioned in the consensus. We hope the updated TDA consensus can serve as a reference for all physicians and can help the physicians providing up-to-dated managements for these patients.

Halved Incidence of Scrub Typhus after Travel Restrictions to Confine a Surge of COVID-19 in Taiwan.

Scrub typhus is a rickettsial disease that is usually transmitted by mite exposure. Infected patients may present with a fever, fatigue, headache, and muscle pain. A blackish skin lesion, called eschar, is pathognomic. The mortality rate in untreated cases is high. The first case of scrub typhus in Taiwan was reported in 1908 during the Japanese colonization. In this article, using the National Infectious Disease Statistics System (NIDSS) from the Taiwan CDC, we analyzed the dynamic incidence of scrub typhus from 2016 to 2021, both seasonally and geographically. In addition, we asked whether the recent travel restrictions and social distancing policy in Taiwan (19 May to 27 July 2021), implemented due to the COVID-19 outbreak, would change the incidence of scrub typhus. The results showed that scrub typhus was most common in summer, with an incidence almost twofold greater than that in winter or spring. Most cases were identified in rural regions. Interestingly, there was a significant 52% reduction in the summer incidence in 2021, compared to the average summer incidence of the past 5 years. This reduction coincided with the countrywide lockdown measures and travel restrictions. The restricted measures for outdoor activities may have contributed to the reduced incidence of scrub typhus.

Arsenic leads to autophagy of keratinocytes by increasing aquaporin 3 expression.

Exposure to arsenic, a ubiquitous metalloid on Earth, results in human cancers. Skin cancer is the most common arsenical cancers. Both autophagy and aquaporin pathway are known to promote carcinogenesis. However, the mechanisms by which arsenic regulates aquaporin and autophagy in arsenical skin cancers remain elusive. This study aims to address how arsenic regulates aquaporin-3, the predominant aquaporin in epidermal keratinocytes, and how this process would induce autophagy. Quantitative real-time PCR and immunofluorescence were used to measure the expression of aquaporin 3 in arsenical skin cancers and arsenic-treated keratinocytes. Beclin-1 expression and autophagy were measured. We examined if blocking aquaporin 3 could interfere arsenic-induced autophagy in keratinocytes. Expression of aquaporin 3 is increased in arsenical cancers and in arsenic-treated keratinocytes. Arsenic induced autophagy in primary human keratinocytes. Notably, the arsenic-induced autophagy was inhibited by pretreatment of keratinocytes with aquaporin inhibitors Auphen or AgNO3, or RNA interference against aquaporin 3. The data indicates that the aquaporin 3 is an important cell membrane channel to mediate arsenic uptake and contributes to the arsenic-induced autophagy.

A population-based study to estimate survival and standardized mortality of tuberous sclerosis complex (TSC) in Taiwan.

BACKGROUND: Tuberous sclerosis complex (TSC) is an autosomal dominant disease with systemic manifestations, which can cause significant mortality and morbidity. Population-based epidemiological studies on TSC mortality and survival remain scarce, though several recent studies provide evidence that TSC survival rates are high and disease prognosis is fair for most patients. This study aims to estimate the life expectancy and mortality statistics in Taiwanese TSC patients, investigate prognosis and associations of TSC mortality based on demographic variables, and compare these results to past literature, especially for Asian patients. METHODS: Taiwanese National Health Insurance (NHI) insurees can obtain Catastrophic Illness Certificates (CIC) for certain eligible diseases to waive copayments after diagnosis by two independent physicians. CIC holders for TSC during 1997-2010 were identified from the NHI Research Database. Queries on enrollment (CIC acquisition) age, endpoint (end of query period or death) age, sex, and comorbidities were obtained. Patients were separated into cohorts (endpoint age, sex, and age of diagnosis), and analyzed accordingly. RESULTS: 471 patients (232 male, 239 female) were identified, of which 14 died. Compared to literature, patients showed similar demographics (age range, diagnosis age, sex distribution); similar manifestations and prevalence (epilepsy, intellectual disability, renal disease); lower disease prevalence (1 in 63,290); lower mortality (0.21% per year); and near-identical standardized mortality ratio (4.99). A cumulative mortality of 4.08% was found over 14 years, though mortality plateaued at 7 years post-enrollment, suggesting a good overall survival rate; comparable with previous studies in Asian patients. Enrollment age was a significant prognostic factor, with late-enrollment (age > 18) patients at higher risk for all-cause mortality (Hazard ratio = 6.54). Average remaining lifetime was significantly lower than the general population, and decreased with age. CONCLUSIONS: This study reports a population-based disease database, highlights the importance of diagnosis age in prognosis prediction, and suggests the role of renal manifestations in mortality. Furthermore, it corroborates recent TSC studies in the Asian population in terms of survival. Overall, physician vigilance, early diagnosis, and careful monitoring are beneficial for disease outcome and patient survival.

GLUT-1 Enhances Glycolysis, Oxidative Stress, and Fibroblast Proliferation in Keloid.

A keloid is a fibroproliferative skin tumor. Proliferating keloid fibroblasts (KFs) demand active metabolic utilization. The contributing roles of glycolysis and glucose metabolism in keloid fibroproliferation remain unclear. This study aims to determine the regulation of glycolysis and glucose metabolism by glucose transporter-1 (GLUT-1), an essential protein to initiate cellular glucose uptake, in keloids and in KFs. Tissues of keloids and healthy skin were explanted for KFs and normal fibroblasts (NFs), respectively. GLUT-1 expression was measured by immunofluorescence, RT-PCR, and immunoblotting. The oxygen consumption rate (OCR) and extracellular acidification rate (ECAR) were measured with or without WZB117, a GLUT-1 inhibitor. Reactive oxygen species (ROS) were assayed by MitoSOX immunostaining. The result showed that glycolysis (ECAR) was enhanced in KFs, whereas OCR was not. GLUT-1 expression was selectively increased in KFs. Consistently, GLUT-1 expression was increased in keloid tissue. Treatment with WZB117 abolished the enhanced ECAR, including glycolysis and glycolytic capacity, in KFs. ROS levels were increased in KFs compared to those in NFs. GLUT-1 inhibition suppressed not only the ROS levels but also the cell proliferation in KFs. In summary, the GLUT-1-dependent glycolysis and ROS production mediated fibroblast proliferation in keloids. GLUT1 might be a potential target for metabolic reprogramming to treat keloids.

Risk of cancer development in patients with keloids.

Keloid is a skin disease characterized by exaggerated scar formation, excessive fibroblast proliferation, and excessive collagen deposition. Cancers commonly arise from a fibrotic microenvironment; e.g., hepatoma arises from liver cirrhosis, and oral cancers arise from submucosal fibrosis. As keloids are a prototypic fibroproliferative disease, this study investigated whether patients with keloids have an increased cancer risk. In a matched, population-based study, first 17,401 patients treated for keloids during 1998-2010 with 69,604 controls without keloids at a ratio of 1:4 were evaluated. The association between keloids and risk of cancer was estimated by logistic regression or Cox proportional hazard regression models after adjustment of covariates. In total, 893 first-time cases of cancer were identified in the 17,401 patients with keloids. The overall cancer risk was 1.49-fold higher in the keloids group compared to controls. Regarding specific cancers, the keloids group, had a significantly higher risk of skin cancer compared to controls (Relative risk = 1.73). The relative risk for skin cancer was even higher for males with keloids (Relative risk = 2.16). Further stratified analyses also revealed a significantly higher risk of developing pancreatic cancer in female patients with keloids compared to controls (Relative risk = 2.19) after adjustment for known pancreatic cancer risk factors. This study indicates that patients with keloids have a higher than normal risk for several cancer types, especially skin cancers (both genders) and pancreatic cancer (females). Therefore, patients with keloids should undergo regular skin examinations, and females with keloids should regularly undergo abdominal ultrasonography.

Nonmuscle Myosin II Activation Regulates Cell Proliferation, Cell Contraction, and Myofibroblast Differentiation in Keloid-Derived Fibroblasts.

Objective: Keloid is an abnormal scar that often develops in high-tension skin. It is caused by excessive fibroblast proliferation and collagen deposition. Nonmuscle myosin IIA (NM-IIA) is an important motor protein that regulates the mechanical transduction of cells. However, the role of NM-IIA in keloid pathogenesis remains unclear. Approach: NM-IIA expression was examined and compared in keloid skin and normal skin by immunofluorescence. The organization of smooth muscle actin (SMA)-mediated stress fibers in normal and keloid fibroblasts (NFs and KFs, respectively) were determined. Cell proliferation and cell contractility were measured in fibroblasts derived from normal and keloids. The NM-II pharmacological inhibitor (blebbistatin) and RNA interference were applied to block NM-IIA and investigate its regulatory role in SMA-mediated stress fibers, cell contractility, and cell proliferation after NM-IIA inhibition. Results: NM-IIA expression is increased in keloid tissue. Inhibition of NM-II by blebbistatin or targeting NM-IIA by RNA interference reduced transforming growth factor beta (TGF-ß)-mediated SMA-mediated stress fiber formation, cell proliferation, and cell contractility of NFs and KFs. Although TGF-ß failed to mediate phosphorylation of myosin light chain (pMLC, the activator of NM-II), pMLC can interact with SMA-mediated stress fiber. Finally, inhibition of NM-II by blebbistatin also reduced NF and KF proliferation after TGF-ß stimulation. Innovation: NM-IIA synergizes with TGF-ß to regulate fibroblast proliferation, contraction activity, and myofibroblasts differentiation. Conclusion: NM-IIA might be one of the therapeutic targets in keloids.

Targeting steroid receptor RNA activator (SRA), a long non-coding RNA, enhances melanogenesis through activation of TRP1 and inhibition of p38 phosphorylation.

Abnormal skin melanin homeostasis results in refractory pigmentary diseases. Melanogenesis is influenced by gene regulation, ultraviolet radiation, and host epigenetic responses. Steroid receptor RNA activator (SRA), a long noncoding RNA, is known to regulate steroidogenesis and tumorigenesis. However, how SRA contributes to melanogenesis remains unknown. Using RNA interference against SRA in B16 and A375 melanoma cells, we observed increased pigmentation and increased expression of TRP1 and TRP2 at transcriptional and translational levels only in B16 cells. The constitutive phosphorylation of p38 in B16-shCtrl cells was inhibited in cells with knocked down SRAi. Moreover, the melanin content of control B16 cells was increased by SB202190, a p38 inhibitor. Furthermore, reduced p38 phosphorylation, enhanced TRP1 expression, and hypermelanosis were observed in A375 cells with RNA interference. These results indicate that SRA-p38-TRP1 axis has a regulatory role in melanin homeostasis and that SRA might be a potential therapeutic target for treating pigmentary diseases.

Selective AhR knockout in langerin-expressing cells abates Langerhans cells and polarizes Th2/Tr1 in epicutaneous protein sensitization.

The aryl hydrocarbon receptor (AhR) represents an environmental sensor regulating immune responses. In the skin, AhR is expressed in several cell types, including keratinocytes, epidermal Langerhans cells (LC), and dermal dendritic cells (DC). The mechanisms how AhR activates or inhibits cutaneous immune responses remain controversial, owing to differences in the cell-specific functions of AhR and the different activating ligands. Therefore, we sought to investigate the role of AhR in LC and langerin+ and negative DC in the skin. To this aim, we generated Langerin-specific and CD11c-specific knockout (-/-) mice lacking AhR, respectively, in LC and Langerin+ dermal DC and in all CD11c+ cells. These were then tested in an epicutaneous protein (ovalbumin, Ova) sensitization model. Immunofluorescence microscopy and flow cytometry revealed that Langerin-AhR-/- but not CD11c-AhR-/- mice harbored a decreased number of LC with fewer and stunted dendrites in the epidermis as well as a decreased number of LC in skin-draining lymph nodes (LN). Moreover, in the absence of AhR, we detected an enhanced T helper type-2 (Th2) [increased interleukin 5 (IL-5) and interleukin 13 (IL-13)] and T regulatory type-1 (Tr1) (IL-10) response when LN cells were challenged with Ova in vitro, though the number of regulatory T cells (Treg) in the LN remained comparable. Langerin-AhR-/- mice also exhibited increased blood levels of Ova-specific immunoglobulin E (IgE). In conclusion, deletion of AhR in langerin-expressing cells diminishes the number and activation of LC, while enhancing Th2 and Tr1 responses upon epicutaneous protein sensitization.

Steroid Receptor RNA Activator, a Long Noncoding RNA, Activates p38, Facilitates Epithelial-Mesenchymal Transformation, and Mediates Experimental Melanoma Metastasis.

Melanoma metastasis signals dismal prognosis even with current checkpoint inhibitors. Long noncoding RNAs (lncRNAs) regulate dynamic metastasis in several cancers, including melanoma. We became interested in a lncRNA, steroid receptor RNA activator (SRA), because it is the first lncRNA also encoding a conserved protein, SRAP, and it regulates progression of prostate and breast cancers. We investigated how SRA mediates melanoma proliferation, migration, invasion, epithelial-mesenchymal transformation (EMT), and metastasis by RNA interference. The expression of SRAP was measured in melanoma tissue and in human and mouse B16 melanoma cells by immunofluorescence and PCR. The results showed that SRA knockdown decreased B16 cell and A375 cell proliferation and inhibited B16 cell migration significantly. Transwell analysis revealed that CCL21-mediated invasion was abolished in SRA-deficient B16 cells. In parallel, p38 dephosphorylation and reciprocal phosphorylation of B-Raf and mitogen-activated protein kinase kinase 1/2 were present in B16-SRA inhibited cells. The induction of EMT markers, ß-catenin and N-cadherin, by CCL21 was reduced in B16-SRA inhibited cells, suggesting that SRA promotes the EMT process. In vivo experimental metastasis showed that B16-SRA inhibited cells formed significantly fewer tumor nodules in the lungs grossly and microscopically. In summary, our results showed that SRA expression is increased in melanoma tissue and that SRA mediates p38 activation, cell invasion, and proliferation and regulates EMT and distant metastasis.

CCL21 Induces mTOR-dependent MALAT1 Expression, Leading to Cell Migration in Cutaneous T-Cell Lymphoma.

BACKGROUND: Mycosis fungoides (MF) is indolent, but may disseminate to leukemia. We reported that C-C motif chemokine ligand 21 (CCL21) is associated with MF invasion and progression. Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), a long noncoding RNA, is associated with several cancer types, however, how it interacts with CCL21 to regulate MF progression, remains unclear. MATERIALS AND METHODS: Expression of long noncoding RNAs MALAT1, antisense noncoding RNA in the INK4 locus (ANRIL), Hox antisense intergenic RNA (HOTAIR), highly up-regulated in liver cancer RNA (HULC), and leukemia-associated non-coding insulin-like growth factor 1 receptor activator RNA 1 (LUNAR1) in tissues from MF was studied using polymerase chain reaction and RNA interference in MF cell line MyLa were used to address this question. RESULTS: Expression of MALAT1 was selectively increased in MF tissues. C-C Chemokine receptor type 7 (CCR7) expression was found to be increased in MyLa cells. CCL21 was found not only to mediate migration, but also to enhance MALAT1 and mammalian target of rapamycin (mTOR) activation in MyLa cells. Knockdown of MALAT1 abrogated CCL21-mediated migration, but not mTOR activation. In contrast, mTOR inhibition reduced CCL21-mediated migration and MALAT1 expression. CONCLUSION: CCL21 induced mTOR activation in MyLa cells, followed by expression of MALAT1, causing cell migration. MALAT1 and mTOR are potential therapeutic targets for MF.

Efficacy and safety of topical SR-T100 gel in treating actinic keratosis in Taiwan: A Phase III randomized double-blind vehicle-controlled parallel trial.

BACKGROUND: Currently available topical treatments for actinic keratosis (AK) are associated with substantial side-effects. OBJECTIVES: To evaluate the efficacy and safety of topical SR-T100 gel in treating AK. METHODS: A multicenter, randomized, double-blinded phase III trial was conducted. Patients with at least two clinically visible AK were enrolled and a punch biopsy was performed on one of the AK to confirm the diagnosis. This study consisted of up to 16-week treatment and 8-week post-treatment periods. Medication was applied daily with occlusive dressing. RESULTS: 123 subjects were recruited and 113 were randomized. 76 subjects were in the SR-T100 and 37 in the vehicle arms. In SR-T100 and vehicle groups, 32.39% and 17.14% of subjects achieved complete clearance, respectively. For 75% partial clearance of lesions, 71.83% and 37.1% of subjects achieved this goal in SR-T100 and vehicle group, respectively. When comparing SR-T100 to vehicle, the odds ratio of complete clearance was 2.14 (p = 0.111), and odds ratio of partial clearance was 4.36 (p < 0.001). Severe local reactions were reported by only one subject using SR-T100. CONCLUSION: The imitation of the study was that not all the treated AK lesions were confirmed by histopathology. The diagnostic uncertainty may contribute to the high partial clearance rate in the vehicle group since the clinical-diagnosed AK showed higher clearance rate compared to histopathology-confirmed AK. The use of occlusive dressing was another possible explanation for high placebo effects. The results suggested that topical SR-T100 gel may be an effective and safe treatment for field therapy of AK.

Hyperpigmentation as a peculiar presentation of mycosis fungoides.

Hyperpigmented mycosis fungoides is an extremely rare subtype of mycosis fungoides. It presents as multiple pigmented macules and patches without poikilodermatous changes and characterized by a CD8+ phenotype on immunohistochemistry. This report describes a typical case of hyperpigmented mycosis fungoides in a 62-year-old woman, who presented with a 7-year history of multiple hyperpigmented macules and patches on the trunk and right leg with progression over this half a year. Histology and immunohistochemical staining of skin samples confirmed the diagnosis of mycosis fungoides. She received psoralen plus ultraviolet A (PUVA) therapy. After an 8-week treatment, the erythematous changes cleared without recurrence during a 6-month follow-up period. An intractable hyperpigmented patch should raise the clinical suspicion of mycosis fungoides with sequential skin biopsy.