Tazarotene, one of the acetylenic class of retinoids, is the 3rd-generation prescription topical retinoid.  It is approved for treating psoriasis, acne, and photo damaged skin  [1].
Tazarotene act as a retinoid prodrug and it is converted to free acid form by rapid deesterification when used in man and animals. Tazarotenic acid shows selectivity for (RAR)-β, and (RAR)-γ though it could bind to all three classes of the retinoic acid receptor (RAR) family, and this may modify gene expression.
Tazarotene mediates these effects by regulating gene transcription. Five nonsmall cell lung carcinoma (NSCLC) cell lines and the constitutive and all-trans retinoic acid (ATRA)-inducible expression of tazarotene-induced gene3 mRNA of the five head and neck squamous cell carcinoma (HNSCC) were examined to determine whether it is associated with their responsiveness to ATRA. Consequently, ATRA induced tazarotene-induced gene3 mRNA from 6 to 12h in most of the responsive cells. Depending on the cell line, the concentration of ATRA required for induction of tazarotene-induced gene3 was ranged from 1 to 500 nm [2].
67 patients aging from 13 to 30 with facial acne attended a study to evaluate the safety and efficacy of topical tazarotene 0.1% cream in the treatment of facial acne. Patients were instructed to apply topical tazarotene cream (0.1%) as a thin film over the affected part in the evening once a day for 12 weeks. And follow-ups were done at 2nd, 4th, 8th and 12th week. As a result, 53% of the patients got remission, 9% had good response, 34% had poor response and 4% of the patients by 12 weeks of treatment was no response. Topical tazarotene cream (0.1%) is an effective and safe treatment method for the face affected by acne vulgaris [3].
References:
[1]. Orlandi A ,Bianchi L, Costanzo A, et al. Evidence of increased apoptosis and reduced proliferation in basal cell carcinomas treated with tazarotene.  Journal of Investigative Dermatology, 2004, 122(4): 1037-1041.
[2]. Higuchi E, Chandraratna RAS, Hong, WK, et al. Induction of TIG3, a putative class II tumor suppressor gene, by retinoic acid in head and neck and lung carcinoma cells and its association with suppression of the transformed phenotype. Oncogene, 2003, 22(30): 4627-4635.
[3]. Zakaria AS, Paul HK, Rahman MA George S K, et al. Topical tazarotene cream (0.1%) in the treatment of facial acne: an open clinical trial. Bangladesh Med Res Counc Bull, 2010, 36(2): 43-46.