Topical gene editing therapeutics using lipid nanoparticles: 'gene creams' for genetic skin diseases?

Patients living with inherited skin diseases have benefitted from recent advances in DNA sequencing technologies that provide new or improved diagnostics. However, developing and delivering new treatments for the "genodermatoses" remains challenging. The goal of creating topical preparations that can recover the inherent gene pathology remains largely aspirational. However, recent progress in two fields, the chemistry of topical delivery formulations (lipid nanoparticles) and the molecular biology of gene repair (CRISPR-Cas9, base and prime editing), now presents new opportunities to address that unmet need. In this review, we discuss how lipid nanoparticle delivery vehicles could be used to deliver gene editing tools to formulate topical "gene creams" suitable for the treatment of genodermatoses. We summarise the historical landscape of topical therapeutics and advances in gene editing which may herald an era of new therapies for patients with inherited skin disorders

In epithelial cancers, aberrant COL17A1 promoter methylation predicts its misexpression and increased invasion

Background: Metastasis is a leading cause of death among cancer patients. In the tumor microenvironment, altered levels of extracellular matrix proteins, such as collagens, can facilitate the first steps of cancer cell metastasis, including invasion into surrounding tissue and intravasation into the blood stream. However, the degree of misexpression of collagen genes in tumors remains understudied, even though this knowledge could greatly facilitate the development of cancer treatment options aimed at preventing metastasis. Methods: We systematically evaluate the expression of all 44 collagen genes in breast cancer and assess whether their misexpression provides clinical prognostic significance. We use immunohistochemistry on 150 ductal breast cancers and 361 cervical cancers and study DNA methylation in various epithelial cancers. Results: In breast cancer, various tests show that COL4A1 and COL4A2 overexpression and COL17A1 (BP180, BPAG2) underexpression provide independent prognostic strength (HR = 1.25, 95% CI = 1.17–1.34, p = 3.03 × 10; HR = 1.18, 95% CI = 1.11–1.25, p = 8.11 × 10; HR = 0.86, 95% CI = 0.81–0.92, p = 4.57 × 10; respectively). Immunohistochemistry on ductal breast cancers confirmed that the COL17A1 protein product, collagen XVII, is underexpressed. This strongly correlates with advanced stage, increased invasion, and postmenopausal status. In contrast, immunohistochemistry on cervical tumors showed that collagen XVII is overexpressed in cervical cancer and this is associated with increased local dissemination. Interestingly, consistent with the opposed direction of misexpression in these cancers, the COL17A1 promoter is hypermethylated in breast cancer and hypomethylated in cervical cancer. We also find that the COL17A1 promoter is hypomethylated in head and neck squamous cell carcinoma, lung squamous cell carcinoma, and lung adenocarcinoma, in all of which collagen XVII overexpression has previously been shown. Conclusions: Paradoxically, collagen XVII is underexpressed in breast cancer and overexpressed in cervical and other epithelial cancers. However, the COL17A1 promoter methylation status accurately predicts both the direction of misexpression and the increased invasive nature for five out of five epithelial cancers. This implies that aberrant epigenetic control is a key driver of COL17A1 gene misexpression and tumor cell invasion. These findings have significant clinical implications, suggesting that the COL17A1 promoter methylation status can be used to predict patient outcome. Moreover, epigenetic targeting of COL17A1 could represent a novel strategy to prevent metastasis in patients

Clinical and laboratory experience of vorinostat (suberoylanilide hydroxamic acid) in the treatment of cutaneous T-cell lymphoma

The most common cutaneous T-cell lymphomas (CTCLs) – mycosis fungoides (MF) and Sézary Syndrome – are characterised by the presence of clonally expanded, skin-homing helper-memory T cells exhibiting abnormal apoptotic control mechanisms. Epigenetic modulation of genes that induce apoptosis and differentiation of malignant T cells may therefore represent an attractive new strategy for targeted therapy for T-cell lymphomas. In vitro studies show that vorinostat (suberoylanilide hydroxamic acid or SAHA), an oral inhibitor of class I and II histone deacetylases, induces selective apoptosis of malignant CTCL cell lines and peripheral blood lymphocytes from CTCL patients at clinically achievable doses. In a Phase IIa clinical trial, vorinostat therapy achieved a meaningful partial response (>50% reduction in disease burden) in eight out of 33 (24%) patients with heavily pretreated, advanced refractory CTCL. The most common major toxicities of oral vorinostat therapy were fatigue and gastrointestinal symptoms (diarrhoea, altered taste, nausea, and dehydration from not eating). Thrombocytopenia was dose limiting in patients receiving oral vorinostat at the higher dose induction levels of 300 mg twice daily for 14 days. These studies suggest that vorinostat represents a promising new agent in the treatment of CTCL patients. Additional studies are underway to define the exact mechanism (s) of by which vorinostat induces selective apoptosis in CTCL cells and to further evaluate the antitumour efficacy of vorinostat in a Phase IIb study in CTCL patients

Staphylococcal enterotoxin A (SEA) stimulates STAT3 activation and IL-17 expression in cutaneous T-cell lymphoma

Cutaneous T-cell lymphoma (CTCL) is characterized by proliferation of malignant T cells in a chronic inflammatory environment. With disease progression, bacteria colonize the compromised skin barrier and half of CTCL patients die of infection rather than from direct organ involvement by the malignancy. Clinical data indicate that bacteria play a direct role in disease progression, but little is known about the mechanisms involved. Here, we demonstrate that bacterial isolates containing staphylococcal enterotoxin A (SEA) from the affected skin of CTCL patients, as well as recombinant SEA, stimulate activation of signal transducer and activator of transcription 3 (STAT3) and upregulation of interleukin (IL)-17 in immortalized and primary patient-derived malignant and nonmalignant T cells. Importantly, SEA induces STAT3 activation and IL-17 expression in malignant T cells when cocultured with nonmalignant T cells, indicating an indirect mode of action. In accordance, malignant T cells expressing an SEA-nonresponsive T-cell receptor variable region β chain are nonresponsive to SEA in monoculture but display strong STAT3 activation and IL-17 expression in cocultures with SEA-responsive nonmalignant T cells. The response is induced via IL-2 receptor common γ chain cytokines and a Janus kinase 3 (JAK3)-dependent pathway in malignant T cells, and blocked by tofacitinib, a clinical-grade JAK3 inhibitor. In conclusion, we demonstrate that SEA induces cell cross talk-dependent activation of STAT3 and expression of IL-17 in malignant T cells, suggesting a mechanism whereby SEA-producing bacteria promote activation of an established oncogenic pathway previously implicated in carcinogenesis

Mycosis fungoides: is it a Borrelia burgdorferi-associated disease?

Mycosis fungoides (MF) is the most frequently found cutaneous T-cell lymphoma with an unknown aetiology. Several aetiopathogenetic mechanisms have been postulated, including persistent viral or bacterial infections. We looked for evidence of Borrelia burgdorferi (Bb), the aetiologic agent of Lyme disease (LD), in a case study of MF patients from Northeastern Italy, an area with endemic LD. Polymerase chain reaction for the flagellin gene of Bb was used to study formalin-fixed paraffin-embedded lesional skin biopsies from 83 patients with MF and 83 sex- and age-matched healthy controls with homolocalised cutaneous nevi. Borrelia burgdorferi-specific sequence was detected in 15 out of 83 skin samples of patients with MF (18.1%), but in none out of 83 matched healthy controls (P<0.0001). The Bb positivity rates detected in this study support a possible role for Bb in the aetiopathogenesis of MF in a population endemic for LD

Malignant inflammation in cutaneous T-cell lymphoma: a hostile takeover

Cutaneous T-cell lymphomas (CTCL) are characterized by the presence of chronically inflamed skin lesions containing malignant T cells. Early disease presents as limited skin patches or plaques and exhibits an indolent behavior. For many patients, the disease never progresses beyond this stage, but in approximately one third of patients, the disease becomes progressive, and the skin lesions start to expand and evolve. Eventually, overt tumors develop and the malignant T cells may disseminate to the blood, lymph nodes, bone marrow, and visceral organs, often with a fatal outcome. The transition from early indolent to progressive and advanced disease is accompanied by a significant shift in the nature of the tumor-associated inflammation. This shift does not appear to be an epiphenomenon but rather a critical step in disease progression. Emerging evidence supports that the malignant T cells take control of the inflammatory environment, suppressing cellular immunity and anti-tumor responses while promoting a chronic inflammatory milieu that fuels their own expansion. Here, we review the inflammatory changes associated with disease progression in CTCL and point to their wider relevance in other cancer contexts. We further define the term "malignant inflammation" as a pro-tumorigenic inflammatory environment orchestrated by the tumor cells and discuss some of the mechanisms driving the development of malignant inflammation in CTCL

Cutaneous T‐cell lymphoma: 2017 update on diagnosis, risk‐stratification, and management

Disease overviewCutaneous T‐cell lymphomas are a heterogenous group of T‐cell lymphoproliferative disorders involving the skin, the majority of which may be classified as Mycosis Fungoides (MF) or Sézary Syndrome (SS).DiagnosisThe diagnosis of MF or SS requires the integration of clinical and histopathologic data.Risk‐adapted therapyTNMB (tumor, node, metastasis, blood) staging remains the most important prognostic factor in MF/SS and forms the basis for a “risk‐adapted,” multi‐disciplinary approach to treatment. For patients with disease limited to the skin, expectant management or skin‐directed therapies is preferred, as both disease‐specific and overall survival for these patients is favorable. In contrast, patients with advanced‐stage disease with significant nodal, visceral or blood involvement are generally approached with biologic‐response modifiers or histone deacetylase inhibitors prior to escalating therapy to include systemic, single‐agent chemotherapy. In highly‐selected patients, allogeneic stem‐cell transplantation may be considered, as this may be curative in some patients.Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/141823/1/ajh24876.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/141823/2/ajh24876_am.pd

Enhancement of cutaneous wound healing by Dsg2 augmentation of uPAR secretion

In addition to playing a role in adhesion, desmoglein 2 (Dsg2) is an important regulator of growth and survival signaling pathways, cell proliferation, migration and invasion, and oncogenesis. While low-level Dsg2 expression is observed in basal keratinocytes and is downregulated in non-healing venous ulcers, overexpression has been observed in both melanomas and non-melanoma malignancies. Here, we show that transgenic mice overexpressing Dsg2 in basal keratinocytes primed the activation of mitogenic pathways, but did not induce dramatic epidermal changes or susceptibility to chemical-induced tumor development. Interestingly, acceleration of full-thickness wound closure and increased wound-adjacent keratinocyte proliferation was observed in these mice. As epidermal cytokines and their receptors play critical roles in wound healing, Dsg2-induced secretome alterations were assessed with an antibody profiler array and revealed increased release and proteolytic processing of the urokinase-type plasminogen activator receptor (uPAR). Dsg2 induced uPAR expression in the skin of transgenic compared to wild-type mice. Wound healing further enhanced uPAR in both epidermis and dermis with concomitant increase in the pro-healing laminin-332, a major component of the basement membrane zone, in transgenic mice. This study demonstrates that Dsg2 induces epidermal activation of various signaling cascades and accelerates cutaneous wound healing, in part, through uPAR-related signaling cascades

Cutaneous T‐cell lymphoma: 2014 Update on diagnosis, risk‐stratification, and management

Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/108042/1/ajh23756.pd