Patients with BRAF-mutated colorectal cancer (BRAFV600E CRC) are currently treated with a combination of BRAF inhibitor and anti-EGFR antibody with or without MEK inhibitor. A fundamental problem in treating patients with BRAFV600E CRC is intrinsic and/or acquired resistance to this combination therapy. By screening 78 compounds, we identified tretinoin, a retinoid, as a compound that synergistically enhances the antiproliferative effect of a combination of BRAF inhibition and MEK inhibition with or without EGFR inhibition on BRAFV600E CRC cells. This synergistic effect was also exerted by other retinoids. Tretinoin, added to BRAF inhibitor and MEK inhibitor, upregulated PARP, BAK, and p-H2AX. When either RARα or RXRα was silenced, the increase in cleaved PARP expression by the addition of TRE to ENC/BIN or ENC/BIN/CET was canceled. Our results suggest that the mechanism of the synergistic antiproliferative effect involves modulation of the Bcl-2 family and the DNA damage response that affects apoptotic pathways, and this synergistic effect is induced by RARα- or RXRα-mediated apoptosis. Tretinoin also enhanced the antitumor effect of a combination of the BRAF inhibitor and anti-EGFR antibody with or without MEK inhibitor in a BRAFV600E CRC xenograft mouse model. Our data provide a rationale for developing retinoids as a new combination agent to overcome resistance to the combination therapy for patients with BRAFV600E CRC.

Post inflammatory hyperpigmentation (PIH) affects all skin types with a heightened predilection for darker skin tones. Its course is chronic once developed and treatment is often difficult. This systematic review aims to summarize the treatment outcomes for PIH with a focus on skin of colour (SOC) individuals. A literature search was conducted using MEDLINE (from 1946), Embase (from 1974), PubMed, and Cochrane in adherence to the Preferred Reporting Items for Systematic Reviews and Meta-Analysis guideline. Results from 48 studies summarized 1356 SOC individuals. The mean age was 29 years (n = 1036) and 78% were female (n = 786). The ethnic prevalence was 70% Black, 27% Asian, and 3% Latin. Overall, 20% were Fitzpatrick skin type (FST) III, 40% FST IV, 34% FST V, and 6% FST VI. Most cases were precipitated by inflammatory conditions (89%) and localized to the face (83%). The most frequently reported interventions were topical retinoids (22%) and laser therapy (17%). Partial improvement was seen in 85% and 66% of participants, respectively. Laser was the only intervention that offered complete resolution in a subgroup of patients (26%); however, there were reported cases of PIH exacerbation following treatment. Chemical peels (9%) and hydroquinone (7%) were among other treatments with less effective outcomes. PIH and its persistence is a prevalent issue, significantly affecting many affected individuals with darker skin tones. Our results show a lack of robust efficacy across all treatment modalities. There is considerable room for improvement in interventions for at-risk populations.

Acne vulgaris is a common, often chronic inflammatory disease that can affect all ages and skin tones. Beyond acute lesions, the sequelae of acne - specifically scarring and dyspigmentation - can be long-lasting, challenging to treat and have substantial psychosocial impact on affected individuals. For acne scarring, treatment modalities include topical, physical, and laser and light therapies, with combination approaches typically yielding optimal outcomes. Trifarotene is a novel fourth generation retinoid with targeted action towards retinoid acid receptor gamma (RAR-γ), the most common isotype found in the epidermis, that has previously been approved for the management of moderate-to-severe facial and truncal acne in individuals over the age of 12 years. Recently, data on trifarotene supports its application in acne scarring. Herein, we provide a succinct review on various treatments for acne scarring and explore how trifarotene and its mechanism of action present an additional topical approach to target atrophic acne scarring.

BACKGROUND: An expert panel of Canadian dermatologists was assembled to develop consensus statements regarding the current landscape of topical therapies for plaque psoriasis and the place in therapy of the recently approved fixed-dose combination halobetasol propionate (HP)/tazarotene (TAZ) lotion (HP/TAZ) in the treatment algorithm for plaque psoriasis.
METHODS: A modified nominal group technique, which combined both independent and group input from the expert panel, was used to develop the consensus statements. The expert panel completed surveys to elicit their independent views on the current landscape of topical therapies for plaque psoriasis in Canada. The first expert panel session was held to discuss the existing body of literature and develop draft consensus statements about topical therapies and the place in therapy of HP/TAZ. Independent feedback on the draft consensus statements was solicited from expert panel members prior to another expert panel session where the amended consensus statements were further discussed, edited and, finally, voted on.
RESULTS: The expert panel reached consensus on 20 statements.
CONCLUSIONS: Expert panel members agreed, based on the existing body of literature, that there is a place in therapy for HP/TAZ to address several current unmet treatment needs of patients with plaque psoriasis. Studies have shown that HP/TAZ is an effective and safe first-line treatment for moderate-to-severe plaque psoriasis. Due to its cosmetically pleasing vehicle and once-daily administration, HP/TAZ may improve patient acceptance and treatment adherence.

暂无摘要。

BACKGROUND: A three-pronged approach to acne treatment combining an antibiotic, antimicrobial, and retinoid may be more efficacious than single/double treatments while potentially reducing antibiotic resistance. This study evaluated the efficacy and safety of the first fixed-dose, triple-combination topical acne product, clindamycin 1.2%/adapalene 0.15%/benzoyl peroxide (BPO) 3.1% gel (CAB) using pooled phase 3 data.
METHODS: In two identical phase 3 (N = 183; N = 180), double-blind, 12-week studies, participants aged ≥ 9 years with moderate-to-severe acne were randomized 2:1 to receive once-daily CAB or vehicle gel. Endpoints included ≥ 2-grade reduction from baseline in Evaluator\'s Global Severity Score and clear/almost clear skin (treatment success) and least-squares mean percent change from baseline in acne lesion counts. Treatment-emergent adverse events (TEAEs) and cutaneous safety/tolerability were evaluated.
RESULTS: At week 12, 50.0% of participants achieved treatment success with CAB versus 22.6% with vehicle gel (P < 0.001). CAB resulted in > 70% reductions in inflammatory and noninflammatory lesions at week 12 (77.9% and 73.0%, respectively), which were significantly greater than vehicle (57.9% and 48.2%; P < 0.001, both). Most TEAEs were of mild-moderate severity, and < 3% of CAB-treated participants discontinued study/treatment because of AEs. Transient increases from baseline in scaling, erythema, itching, burning, and stinging were observed with CAB, but resolved back to or near baseline values by week 12.
CONCLUSIONS: The innovative fixed-dose, triple-combination clindamycin phosphate 1.2%/adapalene 0.15%/BPO 3.1% gel was efficacious and well tolerated in children, adolescents, and adults with moderate-to-severe acne. Half of participants achieved clear/almost clear skin by 12 weeks, rates not previously seen in clinical studies of other topical acne products.
BACKGROUND: ClinicalTrials.gov identifier NCT04214639 and NCT04214652.

OBJECTIVE: Bexarotene has been approved to treat advanced stage cutaneous T-cell lymphomas (CTCL) since 1999. However, very few data have been published on its long-term safety and efficacy profile. The aim of this study is to determine the tolerability to bexarotene and outcomes by collecting the 2nd largest case series to date on its long-term use vs CTCL.
METHODS: This was a multicenter retrospective review of 216 patients with mycosis fungoides (174), or Sézary syndrome (42) on a 10-year course of bexarotene alone or in combination with other therapies at 19 tertiary referral teaching hospitals.
RESULTS: A total of 133 men (62%) and 83 women (38%) were included, with a mean age of 63.5 year (27-95). A total of 45% were on bexarotene monotherapy for the entire study period, 22% started on bexarotene but eventually received an additional therapy, 13% were on another treatment but eventually received bexarotene while the remaining 20% received a combination therapy since the beginning. The median course of treatment was 20.78 months (1-114); and the overall response rate, 70.3%. Complete and partial response rates were achieved in 26% and 45% of the patients, respectively. Treatment was well tolerated, being the most common toxicities hypertriglyceridemia (79%), hypercholesterolemia (71%), and hypothyroidism (52%). No treatment-related grade 5 adverse events were reported.
CONCLUSIONS: Our study confirms bexarotene is a safe and effective therapy for the long-term treatment of CTCL.

暂无摘要。

OBJECTIVE: Bexarotene has been approved to treat advanced stage cutaneous T-cell lymphomas (CTCL) since 1999. However, very few data have been published on its long-term safety and efficacy profile. The aim of this study is to determine the tolerability to bexarotene and outcomes by collecting the 2nd largest case series to date on its long-term use vs CTCL.
METHODS: This was a multicenter retrospective review of 216 patients with mycosis fungoides (174), or Sézary syndrome (42) on a 10-year course of bexarotene alone or in combination with other therapies at 19 tertiary referral teaching hospitals.
RESULTS: A total of 133 men (62%) and 83 women (38%) were included, with a mean age of 63.5 year (27-95). A total of 45% were on bexarotene monotherapy for the entire study period, 22% started on bexarotene but eventually received an additional therapy, 13% were on another treatment but eventually received bexarotene while the remaining 20% received a combination therapy since the beginning. The median course of treatment was 20.78 months (1-114); and the overall response rate, 70.3%. Complete and partial response rates were achieved in 26% and 45% of the patients, respectively. Treatment was well tolerated, being the most common toxicities hypertriglyceridemia (79%), hypercholesterolemia (71%), and hypothyroidism (52%). No treatment-related grade 5 adverse events were reported.
CONCLUSIONS: Our study confirms bexarotene is a safe and effective therapy for the long-term treatment of CTCL.

Among endocrine disruption, interference with the thyroid hormone (TH) regulation is of increasing concern. Respective compounds encode through their structural features both the potential for TH disruption, and the bioavailability mitigating the toxicological effect. The aim of this study is to provide a substructure-based screening-level QSAR (quantitative structure-activity relationship) that discriminates bioavailable TH disruptors from not bioavailable counterparts, covering both direct and indirect (retinoid- and AhR-mediated) modes of action. The QSAR has been derived from literature data for 1642 compounds, and takes into account Lipinski\'s rule-of-five and the brain/blood partition coefficient Kbrain/blood. For its validation, an external test set of 145 substances has been used. For 1787 compounds meeting the model application domain, the model yields only one false negative. The discussion addresses the mechanistic meaning of the bioavailability triggers molecular weight, H-bond donor and acceptor, hydrophobicity (log Kow), and the physicochemical properties underlying log Kbrain/blood. The model may serve as bioavailability-screening step within a decision support system for the predictive assessment of chemicals regarding their potential to disrupt thyroid hormone function in a direct or indirect manner.