Ingenol mebutate for the treatment of actinic keratosis: effectiveness and safety in 246 patients treated in real-life clinical practice

Bioactive diterpenoid metabolism and cytotoxic activities of genetically transformed Euphorbia lathyris roots

Plants in the genus Euphorbia produce a wide variety of pharmacologically active diterpenoids with anticancer, multidrug resistance reversal, and antiviral properties. Some are the primary industrial source of ingenol mebutate, which is approved for treatment of the precancerous skin condition actinic keratosis. Similar to other high value phytochemicals, Euphorbia diterpenoids accumulate at low concentrations in planta and chemical synthesis produces similarly low yields. We established genetically transformed root cultures of Euphorbia lathryis as a strategy to gain greater access to diterpenoids from this genus. Transformed roots produced via stem explant infection with Agrobacterium rhizogenes strain 15834 recapitulated the metabolite profiles of field-grown plant roots and aerial tissues. Several putative diterpenoids were present in transformed roots, including ingenol and closely related structures, indicating that root cultures are a promising approach to Euphorbia-specific diterpenoid production. Treatment with methyl jasmonate led to a significant, albeit transient increase in mRNA levels of early diterpenoid biosynthetic enzymes (farnesyl pyrophosphate synthase, geranylgeranyl pyrophosphate synthase, and casbene synthase), suggesting that elicitation could prove useful in future pathway characterization and metabolic engineering efforts. We also show the potential of transformed E. lathyris root cultures for natural product drug discovery applications by measuring their cytotoxic activities using a panel of human carcinoma cell lines derived from prostate, cervix, breast, and lung.

Prevalence, Discontinuation Rate, and Risk Factors for Severe Local Site Reactions with Topical Field Treatment Options for Actinic Keratosis of the Face and Scalp

Actinic keratoses (AKs) are common lesions on chronically sun damaged skin, which are morphologically characterized by lower third to full thickness atypia of epidermal keratinocytes. These lesions carry a risk of progression towards invasive squamous cell carcinoma (SCC); therefore, treatment of visible lesions and the field in case of field cancerization is recommended. Treatment of AK includes the destruction of atypical keratinocytes that clinically presents with various degrees of erythema, scaling, crusting, erosion, and other visible and subjective symptoms. Such inflammatory reactions may have an impact on the patient’s social life and have shown to decrease compliance and adherence to therapy. Additionally, as various topical treatments have been proven to be effective in treating AK, tolerability of local site reactions (LSRs) might drive the decision for appropriate treatment in an individual scenario. Therefore, we aimed to review prevalence of severe LSRs among various topical treatments for AK. In addition, we summarized discontinuation rates due to LSRs and possible therapy-unrelated risk factors for the development of LSRs with increased severity.

Clinical utility of ingenol mebutate in the management of actinic keratosis: perspectives from clinical practice

Actinic keratoses (AKs) are epidermal cutaneous neoplasia observed predominantly in middle-aged and older subjects with mainly photo type I and photo type II on sun-exposed surfaces as a result of DNA damage. AKs have historically been characterized as being "precancerous"; however, now it is considered by many authors a carcinoma in situ that can persist or progress to invasive squamous cell carcinoma (SCC) with metastatic potential. Despite the advances in the recognition of typical clinic, dermoscopic and histologic patterns, currently it is not yet possible to predict which AKs will progress to SCC. For this reason, early diagnosis and effective therapy are recommended based on cost/risk/benefit analysis. Current treatment consists of lesion-directed or field-directed therapies or a combination of both. Among the topical field therapies, ingenol mebutate stands out for its therapeutic efficacy, both as directed lesion therapy and as field directed therapy. The aim of this review is to demonstrate the utility of ingenol mebutate in the management of AK in daily clinical practice and to highlight data from real world in order to confirm evidence from pivotal studies. In order to explore clinical data from real world, PubMed searches were performed with the search terms "clinical data ingenol mebutate" and "real world ingenol mebutate". The hits were examined for relevant articles using defaults criteria. The timeframe for the sample search started from the first publication on this topic in 2008 up to now. A total of 23 articles were found using the keywords specified above. The overview points out a low number of real-life studies on the effectiveness and tolerability of this novel treatment due to short period of clinical experience for its recent approval. Further real-life studies are required in order to better identify the efficacy, safety and adherence of the drug on a larger population.