Actinic keratoses. Differential diagnosis and treatment

Structure-Based Identification of HIV-1 Nucleocapsid Protein Inhibitors Active against Wild-Type and Drug-Resistant HIV-1 Strains

HIV/AIDS is still one of the leading causes of death worldwide. Current drugs that target the canonical steps of the HIV-1 life cycle are efficient in blocking viral replication but are unable to eradicate HIV-1 from infected patients. Moreover, drug resistance (DR) is often associated with the clinical use of these molecules, thus raising the need for novel drug candidates as well as novel putative drug targets. In this respect, pharmacological inhibition of the highly conserved and multifunctional nucleocapsid protein (NC) of HIV-1 is considered a promising alternative to current drugs, particularly to overcome DR. Here, using a multidisciplinary approach combining in silico screening, fluorescence-based molecular assays, and cellular antiviral assays, we identified nordihydroguaiaretic acid (6), as a novel natural product inhibitor of NC. By using NMR, mass spectrometry, fluorescence spectroscopy, and molecular modeling, 6 was found to act through a dual mechanism of action never highlighted before for NC inhibitors (NCIs). First, the molecule recognizes and binds NC noncovalently, which results in the inhibition of the nucleic acid chaperone properties of NC. In a second step, chemical oxidation of 6 induces a potent chemical inactivation of the protein. Overall, 6 inhibits NC and the replication of wild-type and drug-resistant HIV-1 strains in the low micromolar range with moderate cytotoxicity that makes it a profitable tool compound as well as a good starting point for the development of pharmacologically relevant NCIs.

Actinic cheilitis: clinicopathologic profile and association with degree of dysplasia

BACKGROUND

Actinic cheilitis (AC) is a potentially malignant disorder of the lip caused by exposure to solar radiation.

OBJECTIVES

This study was conducted to evaluate the clinicopathologic profile of cases of AC and to verify associations with the degree of dysplasia.

METHODS

This retrospective study analyzed data for 40 patients with AC. Demographic, clinical, and histopathologic data were evaluated. Sections measuring 5 μm in thickness were cut, deparaffinized, and stained with hematoxylin and eosin for histologic examination. The degree of epithelial dysplasia was graded using the criteria defined by the World Health Organization. Two calibrated oral pathologists analyzed the slides.

RESULTS

Analysis of the AC patients sampled showed that 75.0% were male (P=0.002), 80.0% were aged≥40 years (P<0.001), 74.3% were Caucasian (P=0.004), and 68.6% had occupational exposure to sunlight (P=0.028). The most common clinical manifestation was white lesions (55.0%), and 40.0% of patients had no dysplasia. No significant associations emerged between the histologic grading of AC and gender (P=1.000), age (P=1.000), ethnicity (P=0.416), occupational exposure to sunlight (P=1.000), and clinical presentation (P=0.467).

CONCLUSIONS

The degree of dysplasia in AC was not statistically associated with gender, age, ethnicity, occupational exposure to sunlight, or clinical appearance. This study provides some support for the hypothesis that clinicopathologic features are not related to the degree of dysplasia in AC.

Ingenol mebutate gel 0.015% and 0.05%: in actinic keratosis

Ingenol mebutate is the main active constituent of sap from the plant Euphorbia peplus, which has traditionally been used as a home remedy for various skin conditions. Ingenol mebutate gel is approved in the US, EU, Australia and Brazil for the topical treatment of actinic keratosis. A short course of field-directed therapy with topical ingenol mebutate gel was effective in the treatment of actinic keratoses on the face or scalp (ingenol mebutate gel 0.015% once daily for 3 consecutive days) and on the trunk or extremities (ingenol mebutate gel 0.05% once daily for 2 consecutive days), according to the results of four randomized, double-blind, vehicle-controlled, multicentre studies. Significantly higher complete clearance rates (primary endpoint) and partial clearance rates were seen at day 57 in patients receiving ingenol mebutate gel than in those receiving vehicle gel. Treatment with ingenol mebutate gel was generally associated with sustained clearance of actinic keratoses in the longer term. Topical ingenol mebutate gel was generally well tolerated in the treatment of patients with actinic keratoses on the face or scalp and on the trunk or extremities. Application-site conditions were the most commonly occurring adverse events.

Microarray analysis of cutaneous squamous cell carcinomas reveals enhanced expression of epidermal differentiation complex genes

Gene expression profiles were determined for 12 cutaneous squamous cell carcinomas (SCC) removed from sun-exposed sites on nonimmunosuppressed patients. Gene expression in each SCC was compared to that in sun-exposed skin from the same patient using the Affymetrix HGU133 2.0 PlusGeneChip. We identified 440 genes with increased expression in SCC and 738 with decreased expression; overall we identified a large number of small changes in gene expression rather than a few marked changes that distinguished SCC from sun-exposed skin. Analyzing this robust data set according to biofunctional pathways using DAVID, transcriptional control elements using oPOSSUM, and chromosomal location using GSEA suggested genetic and epigenetic mechanisms of gene expression regulation in SCC. Some altered patterns of gene expression in SCC were consistent with regulation of spatially separated genes by a number of developmentally important transcription factors (forkhead, HMG, and homeo factors) that negatively regulated gene expression and to a few factors that positively regulated expression (Creb-1, NFkappaB, RelA, and Sp-1). We also found that coordinately enhanced expression of epidermal differentiation complex genes on chromosome 1q21 was a hallmark of SCC. A novel finding in our study was enhanced expression of keratin 13 in SCC, a result validated by immunohistochemical staining of an SCC tumor tissue array.

Actinic cheilitis: clinical and pathologic characteristics in 65 cases

OBJECTIVE

The purpose of this study was to determine the clinical and histopathologic presentation of actinic cheilitis.

STUDY DESIGN

A retrospective study on 65 patients attending an Oral Medicine clinic in Greece over a 10 year period. For each case the demographic, clinical and histopathologic information were evaluated.

RESULTS

The mean age at the time of diagnosis was 53.1 +/- 11.4 years. Thirty-nine patients (60%) used tobacco in any form. An outdoor occupation was indicated for 43 (66.2%) patients. The location of the lesions of actinic cheilitis was in all cases on the lower lip. Actinic cheilitis appeared in three forms; white non-ulcerated lesions (29%), erosions or ulcers of the lip (48%), mixed white and erosive (23%). The histopathologic characteristics included increased thickness of keratin layer, alterations of the thickness of spinous cell layer, epithelial dysplasia, connective tissue changes, perivascular inflammation and basophilic changes of connective tissue. In 11 cases (16.9%) the presence of squamous cell carcinoma was observed.

CONCLUSIONS

This case-series highlights varied clinical presentation of actinic cheilitis among whom a high proportion developed squamous cell carcinoma.

Design, synthesis, and biological evaluation of a cephalosporin-monohydroguaiaretic acid prodrug activated by a monoclonal antibody-beta-lactamase conjugate

A novel cephalosporin derivative of monohydroguaiaretic acid (cephem-M(3)N, 7) was synthesized and found to possess anticancer activity against human leukemia (K562), breast carcinoma (MCF7), human lung cancer (A549), human colon cancer (Colo205) and pancreatic cancer cells (Capan2 and MiaPaCa2). A tumor targeting fusion protein (dsFv3-beta-lactamase) was also used in conjunction with cephem-based M(3)N 7 and its potency toward K562, MCF7, A549, Colo205, Capan2, and MiaPaCa2 was found to approach that of the free M(3)N (4). In the presence of dsFv3-beta-lactamase, tumor cells were found to be much more susceptible to conjugate 7 than normal human embryonic lung (HEL) cells and normal fibroblasts (Hef522). These notions provide a new approach to the use of nordihydroguaiaretic acid (NDGA) and its derivatives for antitumor therapy.

Topical treatment of actinic keratoses with 3.0% diclofenac in 2.5% hyaluronan gel

BACKGROUND

Actinic keratoses (AKs) are premalignant skin lesions, which, if left untreated, can develop into squamous cell carcinoma. Current treatments for AKs are destructive and are often associated with significant adverse events. The development of an effective and well-tolerated topical treatment for AK is desirable.

OBJECTIVES

To evaluate the efficacy and safety of 3.0% diclofenac in 2.5% hyaluronan gel as a treatment for AK.

METHODS

This was a multicentre, double-blind, placebo-controlled study in which 195 patients with at least five AKs in up to three designated treatment blocks were randomized to four treatment groups. Patients randomized into the active treatment groups A30 (n = 49) and A60 (n = 48) received topical treatment with 3.0% diclofenac in 2.5% hyaluronan gel 0.5 g twice daily for 30 or 60 days, respectively. Patients in the placebo (vehicle gel) groups V30 (n = 49) and V60 (n = 49) received topical treatment with 2.5% hyaluronan gel 0.5 g twice daily for 30 or 60 days, respectively. Treatment efficacy was assessed by target and cumulative lesion number scores (TLNS and CLNS, respectively) and lesion total thickness score (TTS). Investigator and patient global improvement indices (IGII and PGII) were also used to rate overall improvement.

RESULTS

Compared with placebo, significantly more patients given active treatment for 60 days had TLNS = 0 (33% vs. 10%, P < 0.05; an improvement of 64% compared with 34% with placebo), CLNS = 0 (31% vs. 8%, P < 0.05; an improvement of 54% compared with 23% with placebo) and TTS = 0 (25% vs. 6%, P < 0.05; an improvement of 59% compared with 31% with placebo). The IGII and PGII scores were also significantly better when active treatment was compared with placebo (P < 0.05). Both treatments were generally well tolerated and the incidence of the most common adverse events was similar between groups.

CONCLUSIONS

Treatment with 3.0% diclofenac in 2.5% hyaluronan gel was effective when used for 60 days and was well tolerated in patients with AK.

Incipient intraepidermal cutaneous squamous cell carcinoma: a proposal for reclassifying and grading solar (actinic) keratoses

Actinic keratoses (AKs) are primarily induced by ultraviolet (UV) radiation and are often identified as premalignant lesions. In our opinion, AKs are proliferations of transformed, neoplastic keratinocytes confined to the epidermis that may eventually extend into the dermis, at which point they are termed squamous cell carcinoma (SCC). In contrast to AKs, SCCs have the potential to metastasize and kill. This process is analogous to that of evolving carcinoma of the uterine cervix that has been termed cervical intraepithelial neoplasia (CIN), a time-tested and reliable classification that provides clinicians with accurate information on which to base treatment decisions regarding cervical neoplasms following biopsy testing. A similar classification scheme could provide guidance to clinicians for the diagnosis and treatment of evolving SCC of the skin and as such, we propose a similar classification using the terminology keratinocytic intraepidermal neoplasia (KIN). This system is more reflective of the histology and natural history of SCC and eliminates ambiguity in the terminology of lesions currently referred to as AKs. The KIN classification defines features by which individual specimens can be objectively graded and specific treatment recommendations are made based on the grade of the lesion. We propose that the term keratinocytic intraepidermal neoplasia (KIN) be used to define and describe evolving SCC of the skin and that the term actinic (solar) keratosis be eliminated.