Recommendations for Prevention of Drug Re-Exposure in Toxic Epidermal Necrolysis

Drug re-exposure resulting in Stevens-Johnson syndrome (SJS) or toxic epidermal necrolysis (TEN) is a rare phenomenon and has scarcely been reported. With an aging population, polypharmacy, and a lack of a unified electronic medical record, standard recommendations to prevent or minimize the risk of re-exposure are necessary. We identified five patients, with diagnosis confirmed SJS/TEN, and determined the clinical characteristics and contributing risk factors leading to re-exposure. Polypharmacy, multiple prescribers, advanced age, medical illiteracy, retention of discontinued medications and self-prescribing all contributed to re-exposure in this cohort of patients. This case series demonstrates the potentially deadly effect of drug re-exposure, and the need for both streamlined and integrated medication allergy documentation systems. J Drugs Dermatol. 2019;18(10):1049-1052.

Multifocal pleomorphic dermal sarcoma and the role of inflammation and immunosuppression in a lung transplant patient: a case report.

BACKGROUND: Pleomorphic dermal sarcoma is the cutaneous variant of undifferentiated pleomorphic sarcoma. It is a rare malignancy of unclear histogenesis; it is a diagnosis of exclusion that requires extensive use of immunohistochemistry to rule out other malignancies. Pleomorphic dermal sarcoma typically presents as a solitary tumor in sun-exposed areas and may have unpredictable clinical behavior, with some tumors associated with metastasis and death. CASE PRESENTATION: We present an unusual case of multifocal pleomorphic dermal sarcoma arising in the areas of alpha-1-antitrypsin deficiency panniculitis in a lung transplant patient. Our patient was a 58-year-old white woman whose initial presentation was consistent with alpha-1-antitrypsin deficiency panniculitis. She then developed extensive multifocal, bleeding, and ulcerated nodules in the areas of the panniculitis. A skin biopsy was consistent with a diagnosis of pleomorphic dermal sarcoma. Her immunosuppressive regimen was decreased, and she was treated with liposomal doxorubicin 40 mg/m2 every 3 weeks with some initial improvement in the size of her tumors. However, soon after beginning therapy, she developed pneumonia and septic shock and ultimately died from multi-organ failure. CONCLUSIONS: We hypothesize that chronic, multifocal inflammation in the skin in the setting of immunosuppression led to simultaneous, malignant transformation in numerous skin lesions. We discuss the challenges of diagnosing pleomorphic dermal sarcoma, therapeutic options, and stress the need for multidisciplinary management of these cases.

How to take better photomicrographs: A step-wise approach.

The objective of our study was to establish a detailed photomicrographing protocol for pathologists and dermatopathologists using standard overhead camera and image editing packages. Through a trial-and-error approach we devised a series of steps that comprise our photomicrographing protocol. Descriptive and interpretive data analyses were performed to highlight how each step improves tinctorial quality of digital photomicrographs.

LINE-1 activity and regulation in cancer.

LINE-1 retrotransposons are ubiquitous genetic elements interspersed within the primary nuclear genome of modern day humans. Although shorter LINE-1-derived sequences occupy nearly one-in-five nucleotides of our genome, we are just beginning to appreciate the link between these important genetic elements and cancer, perhaps the most well-studied major degenerative disorder affecting humanity today. Herein, I summarize empirical observations linking LINE-1 to tumorigenesis. The work is organized into three major parts. First, I provide an overview of LINE-1 activity in cancer; highlighting major features of LINE-1 life-cycle such as: promoter methylation, transcription, translation, and retrotransposition. Second, I discuss three genetic pathways - epigenetic regulation, interferon signaling, and genome integrity - as they relate to LINE-1 regulation in cancer. Finally, I review most recent body of work linking LINE-1 as not only a diagnostic cancer biomarker, but also a potential therapeutic target.

Squamous proliferations on the legs of women: Qualitative examination of histopathology, TP53 sequencing, and implications for diagnosis in a series of 30 cases.

BACKGROUND: Women with multiple squamous cell carcinomas (SCCs) of the legs have a striking clinical phenotype. Numerous tumors can develop in a short period of time. OBJECTIVE: Because histopathologic findings can vary in women with multiple SCC lesions, from keratoacanthoma-like to well-differentiated SCC, we hypothesized that TP53 variants might shed light on the appropriate classification. METHODS: We sequenced TP53 in 30 SCCs from 6 women who had multiple SCCs on their legs during a 21-month time frame. RESULTS: Histopathologic analysis showed 16 of the 30 lesions did not have prominent cytologic atypia and were distinguished by having expanded follicle-like structures composed of large, glassy, eosinophilic keratinocytes; these lesions resembled keratoacanthoma and were categorized as keratoacanthoma-like squamous proliferations (KASPs). The 14 remaining tumors had more prominent cytologic atypia and remained classified as SCC. Twenty of 30 tumors (including the KASPs) from the 6 different patients lacked detectable TP53 mutations. Ten of the 14 tumors that remained classified as SCC had detectable TP53 mutations. LIMITATIONS: This is a small series. CONCLUSION: These findings suggest that some cutaneous squamous proliferations on the legs of women with multiple lesions lack prominent cytologic atypia as well as TP53 mutations and might be more akin to keratoacanthoma than SCC or might represent a reactive phenomenon.

Human transposon insertion profiling: Analysis, visualization and identification of somatic LINE-1 insertions in ovarian cancer.

Mammalian genomes are replete with interspersed repeats reflecting the activity of transposable elements. These mobile DNAs are self-propagating, and their continued transposition is a source of both heritable structural variation as well as somatic mutation in human genomes. Tailored approaches to map these sequences are useful to identify insertion alleles. Here, we describe in detail a strategy to amplify and sequence long interspersed element-1 (LINE-1, L1) retrotransposon insertions selectively in the human genome, transposon insertion profiling by next-generation sequencing (TIPseq). We also report the development of a machine-learning-based computational pipeline, TIPseqHunter, to identify insertion sites with high precision and reliability. We demonstrate the utility of this approach to detect somatic retrotransposition events in high-grade ovarian serous carcinoma.

Attenuation of genome-wide 5-methylcytosine level is an epigenetic feature of cutaneous malignant melanomas.

Epigenetic modification of DNA, namely covalent changes of cytosine residues, plays a key role in the maintenance of inactive chromatin regions, both in health and in disease. In the vast majority of malignant melanomas, the most notable known epigenetic abnormality is the attenuation of 5-hydroxymethylcytosine (5-hmC) residues. However, it remains unknown whether a decrease in 5-hmC represents a primary defect of melanoma cancer epigenome or whether it is secondary to the loss of 5-methylcytosine (5-mC), a chemical substrate for 5-hmC. Here, we evaluated 5-mC levels in a spectrum of melanocytic proliferations. To study the epigenetic features of melanocytic nuclei, we began by measuring 5-mC levels in histologic specimens semiquantitatively by immunohistochemistry. We next treated established melanoma cell lines with S-adenosyl methionine (SAM), a universal methyl group donor, in an effort to cause changes in 5-mC levels. We detected a marked reduction in 5-mC levels in both primary and metastatic melanomas compared with 5-mC levels in benign melanocytic nevi. We also empirically induced changes in 5-mC in melanoma cell lines by incubation with SAM. To our surprise, we observed a significant cytoreductive effect of SAM on all melanoma cell lines examined. At subcytotoxic levels, SAM treatment is accompanied by a genome-wide increase in 5-mC. Moreover, we recorded a dose-dependent increase in genome-wide 5-mC levels in melanoma cell lines following SAM treatment. Taken together, we report that genome-wide attenuation of 5-mC is a hallmark of malignant melanomas. We propose that genome-wide attenuation of 5-mC is not merely an epiphenomenon as it is required for melanoma cell growth, albeit by an as of yet undetermined mechanism. Given its potential benefit in slowing down the growth of melanoma cells, SAM should be studied further to determine its role in epigenome modulation.

Somatic retrotransposition is infrequent in glioblastomas.

BACKGROUND: Gliomas are the most common primary brain tumors in adults. We sought to understand the roles of endogenous transposable elements in these malignancies by identifying evidence of somatic retrotransposition in glioblastomas (GBM). We performed transposon insertion profiling of the active subfamily of Long INterspersed Element-1 (LINE-1) elements by deep sequencing (TIPseq) on genomic DNA of low passage oncosphere cell lines derived from 7 primary GBM biopsies, 3 secondary GBM tissue samples, and matched normal intravenous blood samples from the same individuals. RESULTS: We found and PCR validated one somatically acquired tumor-specific insertion in a case of secondary GBM. No LINE-1 insertions present in primary GBM oncosphere cultures were missing from corresponding blood samples. However, several copies of the element (11) were found in genomic DNA from blood and not in the oncosphere cultures. SNP 6.0 microarray analysis revealed deletions or loss of heterozygosity in the tumor genomes over the intervals corresponding to these LINE-1 insertions. CONCLUSIONS: These findings indicate that LINE-1 retrotransposon can act as an infrequent insertional mutagen in secondary GBM, but that retrotransposition is uncommon in these central nervous system tumors as compared to other neoplasias.

A map of mobile DNA insertions in the NCI-60 human cancer cell panel.

BACKGROUND: The National Cancer Institute-60 (NCI-60) cell lines are among the most widely used models of human cancer. They provide a platform to integrate DNA sequence information, epigenetic data, RNA and protein expression, and pharmacologic susceptibilities in studies of cancer cell biology. Genome-wide studies of the complete panel have included exome sequencing, karyotyping, and copy number analyses but have not targeted repetitive sequences. Interspersed repeats derived from mobile DNAs are a significant source of heritable genetic variation, and insertions of active elements can occur somatically in malignancy. METHOD: We used Transposon Insertion Profiling by microarray (TIP-chip) to map Long INterspersed Element-1 (LINE-1, L1) and Alu Short INterspersed Element (SINE) insertions in cancer genes in NCI-60 cells. We focused this discovery effort on annotated Cancer Gene Index loci. RESULTS: We catalogued a total of 749 and 2,100 loci corresponding to candidate LINE-1 and Alu insertion sites, respectively. As expected, these numbers encompass previously known insertions, polymorphisms shared in unrelated tumor cell lines, as well as unique, potentially tumor-specific insertions. We also conducted association analyses relating individual insertions to a variety of cellular phenotypes. CONCLUSIONS: These data provide a resource for investigators with interests in specific cancer gene loci or mobile element insertion effects more broadly. Our data underscore that significant genetic variation in cancer genomes is owed to LINE-1 and Alu retrotransposons. Our findings also indicate that as large numbers of cancer genomes become available, it will be possible to associate individual transposable element insertion variants with molecular and phenotypic features of these malignancies.

Clinical and Histologic Features of Lichenoid Mucocutaneous Eruptions Due to Anti-Programmed Cell Death 1 and Anti-Programmed Cell Death Ligand 1 Immunotherapy.

Importance: Antagonist antibodies to programmed cell death 1 (PD-1) and programmed cell death ligand 1 (PD-L1) have shown remarkable activity in multiple tumor types. Recent US Food and Drug Administration approval of such agents for advanced melanoma, non-small cell lung cancer, and renal cell carcinoma has hastened the need to better characterize their unique toxicity profiles. Objective: To provide a clinical and pathologic description of the lichenoid mucocutaneous adverse effects seen in patients receiving anti-PD-1/PD-L1 treatment. Design, Setting, and Participants: Patients with advanced cancer who were referred to dermatology at Yale-New Haven Hospital, a tertiary care hospital, after developing cutaneous adverse effects while receiving an anti-PD-1 or PD-L1 antibody therapy either as monotherapy or in combination with another agent were identified. Medical records from 2010 to 2015 and available skin biopsy specimens were retrospectively reviewed. Main Outcomes and Measures: Patient demographic characteristics, concurrent medications, therapeutic regimen, type of disease, previous oncologic therapies, clinical morphology of cutaneous lesions, treatment of rash, peripheral blood eosinophil count, tumor response, and skin histologic characteristics if biopsies were available. Results: Patients were 13 men and 7 women, with a mean (range) age of 64 (46-86) years. The majority of cases (16 [80%]) had a clinical morphology consisting of erythematous papules with scale in a variety of distributions. Biopsies were available from 17 patients; 16 (94%) showed features of lichenoid interface dermatitis. Eighteen patients were treated with topical corticosteroids, and only 1 patient required discontinuation of anti-PD-1/PD-L1 therapy. Only 4 of 20 patients (20%) developed peripheral eosinophilia. Sixteen patients (80%) were concurrently taking medications that have been previously reported to cause lichenoid drug eruptions. Conclusions and Relevance: Papular and nodular eruptions with scale, as well as mucosal erosions, with lichenoid features on histologic analysis were a distinct finding seen with anti-PD-1/PD-L1 therapies and were generally manageable with topical steroids. Concurrent medications may play a role in the development of this cutaneous adverse effect.

Somatically Acquired LINE-1 Insertions in Normal Esophagus Undergo Clonal Expansion in Esophageal Squamous Cell Carcinoma.

Squamous cell carcinoma of the esophagus (SCC) is the most common form of esophageal cancer in the world and is typically diagnosed at an advanced stage when successful treatment is challenging. Understanding the mutational profile of this cancer may identify new treatment strategies. Because somatic retrotransposition has been shown in tumors of the gastrointestinal system, we focused on LINE-1 (L1) mobilization as a source of genetic instability in this cancer. We hypothesized that retrotransposition is ongoing in SCC patients. The expression of L1 encoded proteins is necessary for retrotransposition to occur; therefore, we evaluated the expression of L1 open reading frame 1 protein (ORF1p). Using immunohistochemistry, we detected ORF1p expression in all four SCC cases evaluated. Using L1-seq, we identified and validated 74 somatic insertions in eight tumors of the nine evaluated. Of these, 12 insertions appeared to be somatic, not genetically inherited, and sub-clonal (i.e., present in less than one copy per genome equivalent) in the adjacent normal esophagus (NE), while clonal in the tumor. Our results indicate that L1 retrotransposition is active in SCC of the esophagus and that insertion events are present in histologically NE that expands clonally in the subsequent tumor.

Intratumoral multinucleated giant cells are not a prognostic pathologic feature in cutaneous melanoma.

BACKGROUND: Histopathologic diagnostic features such as tumor thickness, ulceration, mitoses, microsatellitosis and nodal metastases are principal pathologic staging components of cutaneous melanomas. We chose to focus on evaluating the presence of multinucleated giant cells in microscopic sections as a putative novel prognosticating diagnostic feature of melanoma. METHODS: We assembled a retrospective cohort comprised of 562 cases of melanoma. We annotated each case for a multitude of known clinicopathologic variables to allow robust statistical evaluation of our cohort. RESULTS: Only 37 cases (6.6%) exhibited the multinucleated giant cells phenotype. Virtually all multinucleated giant cells were localized in the reticular dermis. Of interest, melanomas with multinucleated giant cells were roughly twice more likely to occur on head and neck sites (p = 0.04). Melanomas with multinucleated giant cells phenotype had both comparable melanoma recurrence (p = 0.12) and similar melanoma-specific mortality when compared with melanomas without multinucleated giant cells phenotype (p = 0.26). CONCLUSION: Despite prior anecdotal reports possibly linking multinucleated giant cells phenotype to more aggressive clinical course, we find that melanomas with multinucleated giant cells phenotype is not associated with shorter survival.

Genome-wide characterization of human L1 antisense promoter-driven transcripts.

BACKGROUND: Long INterspersed Element-1 (LINE-1 or L1) is the only autonomously active, transposable element in the human genome. L1 sequences comprise approximately 17 % of the human genome, but only the evolutionarily recent, human-specific subfamily is retrotransposition competent. The L1 promoter has a bidirectional orientation containing a sense promoter that drives the transcription of two proteins required for retrotransposition and an antisense promoter. The L1 antisense promoter can drive transcription of chimeric transcripts: 5' L1 antisense sequences spliced to the exons of neighboring genes. RESULTS: The impact of L1 antisense promoter activity on cellular transcriptomes is poorly understood. To investigate this, we analyzed GenBank ESTs for messenger RNAs that initiate in the L1 antisense promoter. We identified 988 putative L1 antisense chimeric transcripts, 911 of which have not been previously reported. These appear to be alternative genic transcripts, sense-oriented with respect to gene and initiating near, but typically downstream of, the gene transcriptional start site. In multiple cell lines, L1 antisense promoters display enrichment for YY1 transcription factor and histone modifications associated with active promoters. Global run-on sequencing data support the activity of the L1 antisense promoter. We independently detected 124 L1 antisense chimeric transcripts using long read Pacific Biosciences RNA-seq data. Furthermore, we validated four chimeric transcripts by quantitative RT-PCR and Sanger sequencing and demonstrated that they are readily detectable in many normal human tissues. CONCLUSIONS: We present a comprehensive characterization of human L1 antisense promoter-driven transcripts and provide substantial evidence that they are transcribed in a variety of human cell-types. Our findings reveal a new wide-reaching aspect of L1 biology by identifying antisense transcripts affecting as many as 4 % of all human genes.

Cell and Tissue Display: An Alternative Multipurpose Tool for Microscopy.

We developed a method, termed Cell and Tissue Display (CTD), for embedding 16 or more different tissue samples in multi-compartment agarose blocks. The CTD-generated blocks allow uniform multiplexing of cell lines and small tissue fragments within a single histologic block. The distribution of individual cells within the CTD blocks is improved, likely because the individual agarose compartments are small and uniform. The composition of each CTD block can be customized based on intended use. Some potential uses of CTD histologic blocks include improved sectioning of small tissue fragments, such as needle biopsy specimens or punch biopsies; multiplexing of tissue fragments within a single block; and the generation of control slides for laboratory proficiency testing. .

Immunodetection of Human LINE-1 Expression in Cultured Cells and Human Tissues.

Long interspersed element-1 (LINE-1) is the only active protein-coding retrotransposon in humans. It is not expressed in somatic tissue but is aberrantly expressed in a wide variety of human cancers. ORF1p protein is the most robust indicator of LINE-1 expression; the protein accumulates in large quantities in cellular cytoplasm. Recently, monoclonal antibodies have allowed more complete characterizations of ORF1p expression and indicated potential for developing ORF1p as a clinical biomarker. Here, we describe a mouse monoclonal antibody specific for human LINE-1 ORF1p and its application in immunofluorescence and immunohistochemistry of both cells and human tissues. We also describe detection of tagged LINE-1 ORF2p via immunofluorescence. These general methods may be readily adapted to use with many other proteins and antibodies.

Diagnostic utility of 5-hydroxymethylcytosine immunohistochemistry in melanocytic proliferations.

Decreased hydroxymethylated cytosine (5-hydroxymethycytosine, 5-hmC) is reported to correlate with melanocyte dysplasia. The purpose of this study was to assess the diagnostic utility of this observation. 5-hmC immunohistochemistry was performed on tissue microarrays containing 171-melanocytic lesions from two different institutions. An immunohistochemical staining score representing the percentage and intensity of nuclear staining was assigned. The performance characteristics of 5-hmC immunohistochemistry for discriminating between a nevus and melanoma were determined. Additional cases of melanoma arising in a nevus (n = 8), nodal nevi (n = 5) and melanoma micrometastases to a lymph node (n = 6) were also assessed. Pronounced 5-hmC loss was observed in melanomas when compared with nevi (mean ± standard deviation = 6.71 ± 11.78 and 55.19 ± 23.66, respectively, p < 0.0001). While the mean immunohistochemical staining score values for melanocytic nevi and melanoma were distinct, there was considerable variability in immunohistochemical staining score within a single diagnostic category. The sensitivity and specificity of this assay for nevus vs. melanoma is 92.74 and 97.78%, respectively. Distinct biphasic staining patterns were observed in cases of melanoma arising in association with a nevus. Relative changes of 5-hmC expression within a single lesion may be more informative than absolute values when using 5-hmC as a diagnostic adjunct.

Retrotransposon insertions in the clonal evolution of pancreatic ductal adenocarcinoma.

Pancreatic ductal adenocarcinoma (PDAC) is typically diagnosed after the disease has metastasized; it is among the most lethal forms of cancer. We recently described aberrant expression of an open reading frame 1 protein, ORF1p, encoded by long interspersed element-1 (LINE-1; L1) retrotransposon, in PDAC. To test whether LINE-1 expression leads to somatic insertions of this mobile DNA, we used a targeted method to sequence LINE-1 insertion sites in matched PDAC and normal samples. We found evidence of 465 somatic LINE-1 insertions in 20 PDAC genomes, which were absent from corresponding normal samples. In cases in which matched normal tissue, primary PDAC and metastatic disease sites were available, insertions were found in primary and metastatic tissues in differing proportions. Two adenocarcinomas secondarily involving the pancreas, but originating in the stomach and duodenum, acquired insertions with a similar discordance between primary and metastatic sites. Together, our findings show that LINE-1 contributes to the genetic evolution of PDAC and suggest that somatic insertions are acquired discontinuously in gastrointestinal neoplasms.