Efficacy and safety of topical administration of tacrolimus in oral lichen planus: An updated systematic review and meta-analysis of randomized controlled trials

Topical tacrolimus orabase versus topical clobetasol propionate orabase in the treatment of symptomatic oral lichen planus: a pilot randomized study

OBJECTIVES

This pilot study aimed to compare the efficacy of 0.1% tacrolimus and 0.05% clobetasol propionate in orabase for treating symptomatic oral lichen planus (OLP).

MATERIALS AND METHODS

Pilot, randomized, and controlled study conducted on 21 patients with symptomatic OLP, selected according to the clinical and histopathological criteria of Cheng et al. 2016. Twelve patients received 0.1% tacrolimus, and nine received 0.05% clobetasol, both in orabase for 30 days with a two-month follow-up. The patients were examined for scores of signs (ODSS), symptoms (VAS), quality of life (OHIP-14), anxiety (Beck Anxiety Scale), and treatment satisfaction (Hedonic Scale).

RESULTS

Both treatments were effective in reducing ODSS, VAS, and Beck Anxiety Scale scores and performed well on the hedonic scale, yet without statistical difference between them. However, at the 1-month follow-up, patients in group Clobetasol showed a greater percentage reduction in ODSS score compared to baseline by 50% (p = 0.02) and significantly lower average values (p = 0.03) than those in group Tacrolimus. Longitudinal intragroup analysis revealed significant improvements over time in both groups for ODSS, and only in the tacrolimus group for OHIP-14 and Beck scores.

CONCLUSIONS

Both tested protocols were effective over a three-month follow-up. However, due to the lower cost of clobetasol propionate it can be considered the first-choice option. Tacrolimus in orabase formulation may be a promising alternative for refractory lesions that do not respond to topical steroids.

CLINICAL RELEVANCE

Managing symptomatic OLP is challenging. Comparisons between tacrolimus and clobetasol propionate in orabase formulations have not yet been thoroughly explored.

Upregulation of IL-37 in epithelial cells: A potential new mechanism of T cell inhibition induced by tacrolimus

Oral lichen planus (OLP) is a chronic T cell-mediated mucocutaneous disease characterized by T cell infiltration at the connective tissue-epithelium interface. Traditionally, topical corticosteroids are used as the first-line drugs to treat OLP. However, long-term use of corticosteroids may lead to drug tolerance, secondary candidiasis, and autoimmune adrenal insufficiency. Although topical tacrolimus has often been recommended for short-term use in corticosteroid-refractory OLP, the precise role of tacrolimus in epithelial cells remains elusive. This study showed that tacrolimus could directly upregulate the expression of IL-37 in human gingival epithelial cells by promoting the TGF-βRI/Smad3 pathway independently of calcineurin inhibition and MAPKs. In contrast, dexamethasone, one of the corticosteroids, did not have the same effect. Moreover, IL-37 could inhibit the proliferation of activated T cells and the secretion of effector cytokines and alleviate epithelial cell apoptosis and death caused by activated T cells ina co-culturesystem. Furthermore, compared with healthy controls, IL-37 and p-Smad3 levels significantly increased in the oral mucosa affected by OLP, especially in the epithelium. IL-37 might have mediated a negative feedback mechanism to curb excessive inflammation in OLP. However, the expression of IL-37 was not associated with the infiltration of CD8+ T cells and Tregs in OLP, implying that IL-37 might mostly affect T cell activation rather than T cell differentiation and migration. Overall, this study discovered a potential novel mechanism by which tacrolimus might indirectly inhibit T cell-mediated immune damage by upregulating IL-37 in human gingival epithelial cells.

Efficacy of Platelet-Rich Plasma Therapy in Oral Lichen Planus: A Systematic Review

Background and Objectives: Oral lichen planus (OLP) is an autoimmune, mucocutaneous, oral potentially malignant disorder (OPMD), which characteristically manifests with chronic, recalcitrant lesions, with frequent flare-ups and remissions. The precise etiopathogenesis of OLP is still debatable, although it is believed to be a T-cell-mediated disorder of an unidentified antigen. Despite the availability of various treatments, no cure for OLP exists due to its recalcitrant nature and idiopathic etiology. Platelet-rich plasma (PRP) has antioxidant, anti-inflammatory, and immunomodulatory properties, in addition to its regulatory action on keratinocyte differentiation and proliferation. These salient properties substantiate the possible role of PRP in the treatment of OLP. Our systematic review focuses on assessing the therapeutic potential of PRP as a treatment modality in OLP. Materials and Methods: We conducted a detailed literature search for studies assessing PRP as a therapeutic regimen in OLP, using the Google Scholar and PubMed/MEDLINE search engines. The search was limited to studies published from January 2000 to January 2023 and included a combination of Medical Subject Heading (MeSH) terms. ROBVIS analysis was carried out for the assessment of publication bias. Descriptive statistics were performed using Microsoft Excel. Results: This systematic review included five articles that met the inclusion criteria. Most of the included studies demonstrated that PRP treatment considerably ameliorated both objective and subjective symptoms in OLP subjects, with comparable efficacy to the standard corticosteroid treatment. Further, PRP therapy offers the added benefit of minimal adverse effects and recurrences. Conclusion: This systematic review suggests that PRP has significant therapeutic potential for treating OLP. However, further research with larger sample sizes is imperative to corroborate these findings.

Evaluation of muco-adhesive tacrolimus patch on caspase-3 induced apoptosis in oral lichen planus: a randomized clinical trial

BACKGROUND

The study compared the clinical effectiveness of topical Tacrolimus (TAC) in patches or gel with Triamcinolone acetonide (TRI) gel for erosive/atrophic oral lichen planus (OLP) and investigated the influence of these therapies on Caspase-3 expression as a marker of apoptosis.

METHODS

Thirty patients were randomly assigned into three equal groups to receive either topical TAC 0.1% patch twice daily, topical TAC 0.1% gel, or topical TRI 0.1% gel four times daily for 8 weeks. Each patient's clinical score (CS), visual analogue scale (VAS), and total atrophic area (TAA) of the marker lesion were measured at baseline, 2, 4, and 8 weeks of treatment, as well as after 4 weeks of treatment free period. Caspase-3 expression and lymphocytic counts (LC) were assessed in pre- and post-treatment biopsied stained sections.

RESULTS

TAC patch resulted in a higher reduction in CS [- 14.00 (15.54%)] and VAS [- 70.21 (15.82%)] followed by TAC gel then TRI gel within the first two weeks. The reduction in VAS and TAA were significantly higher in TAC groups compared to TRI gel, although the difference between TAC treatment was not significant and this was observed throughout the treatment and follow-up periods. Caspase-3 expression increased in connective tissue in all groups. It decreased significantly within the epithelium in both TAC groups but increased in TRI gel. (LC) were significantly lowered with the TAC patch compared to other groups. The percentage change in Caspase-3 epithelial expression was significantly correlated to the CS, TAA, and LC.

CONCLUSION

Both TAC patch and gel significantly decreased pain and lesion size than TRI gel, with a significant reduction in Caspase-3 expression within the epithelium in comparison to the increase seen with TRI gel. The study protocol was registered at www.

CLINICALTRIALS

gov (NCT05139667) on 01/12/2021.

Glutamine promotes the proliferation of epithelial cells via mTOR/S6 pathway in oral lichen planus

BACKGROUND

Although abnormal cell proliferation and apoptosis are associated with the pathogenesis of oral lichen planus (OLP), the exactly mechanism of which is not yet known. It has been reported that glutamine (Gln) can promote cell proliferation and inhibit apoptosis of various tumor cells. This study aims to evaluate the effect of Gln metabolism on the balance of proliferation and apoptosis in epithelial cells of OLP.

METHODS

Thirty human OLP specimens and 11 normal controls were stained by immunohistochemistry to detect the levels of proliferation and Gln metabolism related proteins. Then, the critical role of Gln in cell proliferation and apoptosis was determined by Gln deprivation or treatment with glutaminase inhibitor (CB-839) to intervene Gln metabolism in human gingival epithelial cells. Cell proliferation was detected using CCK8, p-mTOR and p-S6 proteins were detected using Western Blot, cell apoptosis and cell cycle were detected using flow cytometry, and cell stress was detected using immunofluorescence.

RESULTS

Compared with normal controls, OLP specimens showed higher levels of Ki-67 and Gln metabolism-related proteins, including Gln transporter (ASCT2), glutaminase (GLS), and pathway proteins (p-mTOR and p-S6). In vitro, Gln promoted cell proliferation and simultaneously upregulated the activity of mTOR/S6 pathway. Moreover, rapamycin, an mTOR pathway inhibitor, could effectively block the Gln-induced cell proliferation. MHY1485, an mTOR pathway agonist, could effectively reverse the decline of cell proliferation under Gln deprivation. In addition, inhibiting Gln metabolism caused the accumulation of intracellular radical oxygen species (ROS) and induced cell apoptosis. However, N-acetylcysteine reversed this state and then decreased cell apoptosis by eliminating intracellular ROS.

CONCLUSION

Gln metabolism is essential to maintain the balance of proliferation and apoptosis in oral epithelial cells, and inhibition of Gln metabolism may have a beneficial effect on OLP treatment.

Lichenoid lesions of the upper labial mucosa: a systematic review and a report of a new case with extensive follow-up

OBJECTIVES

The paper reports the demographic characteristics of patients with lichenoid lesions affecting only the upper labial mucosa, with or without associated lesions in the maxillary anterior gingiva, alongside the lesions' clinical and histopathological features, treatment, follow-up and prognosis. Also, a new case with lengthy follow-up is presented.

MATERIALS AND METHODS

A systematic review was performed in line with PRISMA guidelines. The literature search sources were PubMed, Scopus and Web of Science.

RESULTS

In all, 26 patients (21 women, 5 men) were included in the review. 80.8% (n = 21) of the labial lesions were clinically erythematous and 19.2% (n = 5) were accompanied by white striations. The gingiva was affected in 46.2% of cases. All patients (100%, n = 24) reported symptoms. All of the lesions presented histological features of lichenoid inflammation. Granulomas were noted in 65.4% (n = 17) of the lesions. Topical corticosteroid was the most frequent therapy (89.5%, n = 17).

CONCLUSIONS

Lichenoid lesions found solely in the upper labial mucosa, with or without adjacent gingival lesions, are rarely reported in the literature, and the reporting is often incomplete. A definitive aetiology could not be established for the lesions. Likewise, there is little information about this condition's long-term prognosis.

Outcome and long-term treatment protocol for topical tacrolimus in oral lichen planus

BACKGROUND AND OBJECTIVE

Topical tacrolimus has been shown to be beneficial in the treatment of oral lichen planus (OLP). However, long-term effects and its optimal application protocol with gradual reduction have not been studied. Accordingly, we analysed the clinical response of OLP to tacrolimus in our daily clinical practice with a focus on the optimal long-term therapeutic scheme.

METHODS

Retrospective analysis of all consecutive patients diagnosed with OLP and treated with topical tacrolimus (0.03% oral rinse) in a clinical setting between 2015 and 2020. The objective clinical response was measured by a 4-point scale (complete remission, major remission, partial remission and no response), and subjective impairment by a 3-point scale (severe, moderate and none).

RESULTS

Fifty-seven patients (74% women; median age: 66 years) were included. Fifty-six (98%) patients had prior treatment with topical steroids. After introduction of tacrolimus, objective remission (major or complete) was reached by 28%, 62%, 87% and 97% of patients after 3, 6, 12 and 24 months respectively. Subjective remission was reported by 16%, 48%, 69% and 83% after 3, 6, 12 and 24 months of treatment respectively. The treatment frequency could be gradually reduced from initially twice daily to once daily or less in 28%, 61%, 78% and 87% after 3, 6, 12 and 24 months respectively; 41% of patients completely suspended the treatment at one point, but 67% of them experienced a relapse after a median time of 3.3 months. Four patients (7%) developed a squamous cell carcinoma (SCC) during the observation period. Otherwise, there were only few and minor side-effects.

CONCLUSION

Topical tacrolimus can be an effective second-line therapy for OLP refractory to potent topical corticosteroids. The therapy frequency can often be reduced during the maintenance period. Both signs of clinical activity and subjective impairment should guide therapy. Regular follow-up is necessary to recognize possible SCC.