Squamous cell carcinoma of the oral cavity associated with graft versus host disease: report of a case and review of the literature

Perspectives on oral chronic graft-versus-host disease from immunobiology to morbid diagnoses

Chronic Graft-versus-Host Disease (cGVHD) is a major long-term complication, associated with morbidity and mortality in patients following allogenic hematopoietic cell transplantation (HCT) for immune hematopoietic disorders. The mouth is one of the most frequently affected organs after HCT (45-83%) and oral cGVHD, which may appear as the first visible sign. Manifestations present with mucosal lichenoid lesions, salivary gland dysfunction and limited oral aperture. Diagnosis of oral cGVHD severity is based on mucosal lesions with symptoms of sensitivity and pain and reduced oral intake. However, diagnostic difficulties arise due to subjective definitions and low specificity to cover the spectrum of oral cGVHD. In recent years there have been significant improvements in our understanding of the underlying oral cGVHD disease mechanisms. Drawing upon the current knowledge on the pathophysiology and biological phases of oral cGVHD, we address oral mucosa lichenoid and Sjogren's Syndrome-like sicca syndromes. We consider the response of alloreactive T-cells and macrophages to recipient tissues to drive the pathophysiological reactions and biological phases of acute inflammation (phase 1), chronic inflammation and dysregulated immunity (phase 2), and subsequent aberrant fibrotic healing (phase 3), which in time may be associated with an increased malignant transformation rate. When formulating treatment strategies, the pathophysiological spectrum of cGVHD is patient dependent and not every patient may progress chronologically through the biological stages. As such there remains a need to address and clarify personalized diagnostics and management to improve treatment descriptions. Within this review, we highlight the current state of the art knowledge on oral cGVHD pathophysiology and biological phases. We address knowledge gaps of oral cGVHD, with a view to facilitate clinical management and improve research quality on lichenoid biology and morbid forms of oral cGVHD.

Are second primary head and neck cancers with previous hematological malignancy more aggressive than de novo head and neck cancers?

OBJECTIVES

Secondary solid tumors can occur after the treatment of hematological malignancies and are associated with a poor prognosis. We evaluated the survival outcomes of patients with second primary head and neck cancers according to the site of cancer origin, type of hematological malignancy, and age.

MATERIALS AND METHODS

We enrolled all patients who underwent surgery for second primary head and neck cancer and were previously treated for hematological malignancy between 1997 and 2020. We analyzed the survival outcomes of patients with second primary head and neck cancer, and compared them with 3126 de novo head and neck cancer patients diagnosed during the same period at our hospital.

RESULTS

The 5-year overall survival (OS) rate was significantly worse for second primary head and neck cancer patients than de novo cancer patients (52.0 % and 77.9 %, respectively; p = 0.04) and those results were similarly observed in second primary oral cavity cancer (33.3 % and 75.7 %, respectively; p < 0.01). Patients with myelodysplastic syndrome and acute myeloid leukemia showed significantly worse 5-year OS rate than those with other types of hematological malignancies (p = 0.036). Multivariate analysis showed that bone marrow transplantation (BMT) was a risk factor for the recurrence of head and neck cancers (odds ratio = 6.635, p = 0.042).

CONCLUSION

Patients with second primary head and neck cancer, particularly of the oral cavity, had a worse prognosis than patients with de novo head and neck cancer. BMT predicts recurrence in second primary head and neck cancer patients.

Oral Cancer in HSCT Pediatric Patients Arising on GVHD: A Comprehensive Review

After haematopoietic stem cell transplantation and a history of GVHD, the risk of developing secondary malignancies, including oral cancer, is higher. This risk increases with time post-transplantation; therefore, pediatric patients undergoing HSCT, who have long-term survival chances, are in a high-risk category. The aim of this review is to provide data on HSCT, GVHD, clinical manifestations, histological features and treatment of oral cancer, and outcomes in HSCT pediatric patients, affected by oral GVHD, who have been developed OSCC. Descriptive statistics were used to validate data. Fifteen studies on a total of 33 patients were selected. Data on oral cancer showed that the tongue was the most frequently involved site (13 pts; 39.39%), followed by the floor of the mouth (4 pts; 12.12%), and buccal mucosa (4 pts; 12.12%). Oral squamous cell carcinoma was the histological feature reported. There were 19 (57.58%) deaths occurring between 2 and 46.5 months after OC diagnosis. Eleven patients survived with a median follow-up of 34 months. Considering the high risk of developing oral cancer, a conventional oral examination every 6 months is recommended for HSCT pediatric patients who have developed GVHD.

Implementation of Routine Endoscopy with Narrow Band Imaging in the Evaluation of Oral and Upper Airways Lesions in Oral Chronic Graft-Versus-Host Disease: A Preliminary Study

(1) Background: The aim of our study is to investigate the main oral lesion patterns in patients with oral graft-versus-host disease and to describe and validate the use of endoscopy enhanced with narrow-band imaging (NBI) as a personalized, reliable and user-friendly tool for the early detection of oral potentially diseases. (2) Methods: We retrospectively evaluated the medical records of 20 patients with chronic GVHD and with oral manifestations, who were referred to our “Interdisciplinary Center for Oropharyngeal Pathology (CIPO)” from January 2017 to July 2022. (3) Results: Data on GVHD, oral localization and NBI endoscopic evaluation are collected. A total of six mucositis, one mucosal erythematous change, ten lichenoid-like changes, eight erosive lesions, one leukoplakia, two erythroplakia and two case of blisters were observed. Two vascular abnormalities were seen with NBI, leading to one excisional biopsy. The patient was diagnosed with squamous cell carcinoma. (4) Conclusion: Our study is the first to highlight the relevance of the routine use of endoscopy with NBI in patients with oral chronic GVHD. We highlighted its role as a reliable, reproducible, easy-to-use and tailor-made tool in the follow-up of those patients and to allow an earlier identification of aberrant neoangiogenesis related to oral potentially malignant disorders and oral cancer.

Oral Chronic Graft-Versus-Host Disease

Chronic oral graft-versus-host disease (cGVHD) is a complex, frequent, and highly impactful complication of allogeneic hematopoietic cell transplantation (alloHCT). It represents the leading cause of morbidity and mortality in long-term alloHCT survivors. cGVHD can affect almost any visceral organ system and commonly affects the skin, eyes and mouth, manifesting with signs and symptoms similar to other known immune-mediated and autoimmune diseases. Oral manifestations of GVHD include inflammation, thinning, and ulceration of oral mucosal tissues (similar to lichen planus), lymphocyte-mediated salivary gland dysfunction (similar to Sjögren/Sicca Syndrome), and decreased oral opening (trismus) secondary to sclerosis of oral and perioral tissues (analogous to limitation in scleroderma). Potential sequelae include severe mucosal pain, compromised nutrition, weight loss, limitation in opening, and sometimes irreversible fibrosis of the salivary glands. While some cases can be managed with topical therapies, management may also require long-term targeted immunosuppressive and/or corticosteroid therapy with associated risk of local and systemic infection, hyperglycemia, kidney dysfunction, osteopenia/osteoporosis, and possibly secondary malignancies. The aim of this mini-review is to provide an up-to-date review of literature related to the diagnosis and management of oral cGVHD to aid dental and medical clinicians in optimizing oral cGVHD therapy while minimizing potential adverse effects.

Herpes simplex virus-infected squamous cell carcinoma: a case report

BACKGROUND

Herpes simplex virus (HSV)-1 is a highly prevalent, non-oncogenic virus that has higher morbidity in immunocompromised hosts. Its most common clinical manifestation is superficial ulceration of the integument or mucus membranes.

CASE PRESENTATION

A 65-year-old woman with a history of acute myelogenous leukemia treated with allogenic peripheral blood stem cell transplant presented for resection of an ulcerated buccal squamous cell carcinoma. We report a case of HSV-1-infected malignant cells discovered on histopathological examination of the carcinoma specimen ultimately treated with valacyclovir.

CONCLUSIONS

HSV-1 is not considered an oncogenic virus itself but may increase risk of malignant progression. Cancer cells are vulnerable to superimposed viral infections, including HSV-1, which likely led to the findings in this case.

Two Lip Carcinomas following Allogeneic Hematopoietic Stem Cell Transplantation: A Case Report and Literature Review

Background

Secondary solid cancers are severe complications in patients who have undergone allogeneic hematopoietic stem cell transplantation (AHSCT) for malignant and nonmalignant lymphohematopoietic diseases.

Objective

The aim of this work was to report a case of two lip carcinomas following AHSCT and to warn doctors about the importance of regular check-ups of patients who have received HSCT. Observation. A 57-year-old man was referred by the dermatology department for the management of exophytic budding lesions on the lower lip evolving since 5 months. The patient was in complete remission following allogeneic bone marrow transplantation for acute myeloid leukemia since five years. Clinical and histological findings confirmed the diagnosis of a squamous cell carcinoma of the two lesions.

Conclusion

It is of paramount importance to seek an oral squamous cell carcinoma in the presence of persistent lesions in HSCT recipients.

Oral granuloma in a pediatric patient with chronic graft-versus-host disease: A case report

BACKGROUND

Oral mucositis is often observed with graft-versus-host disease (GVHD); however, the occurrence of oral granuloma is rare. The rapid increase in granulomatous lesions should be distinguished from malignant tumors in patients with GVHD because malignant diseases can develop in those patients. This case is the youngest pediatric patient with granuloma associated with GVHD.

CASE SUMMARY

The patient was a 1-year and 5-mo-old girl who presented to our department for the management of oral nodules. At the age of 5 mo, she was diagnosed with primary immunodeficiency disease, cord blood transplant was performed at 11 mo and bone marrow transplant at 1 year of age. After transplantation, GVHD and oral mucositis developed, and tacrolimus was administered. Interestingly, nodules appeared on the lower lip and buccal mucosa, which spontaneously disappeared. Then, a new nodule appeared on the left lateral border of the tongue. Resection was performed and the histopathological diagnosis was granuloma. The origin of these nodules were considered to be the fibroblasts activated under inflammation caused by GVHD because the calcineurin inhibitor tacrolimus acted on their proliferation.

CONCLUSION

It is very important to distinguish oral granulomatous lesions from malignancies if GVHD is present at the base and if immunosuppressive agents and steroids are being administered.

Oral potentially malignant disorders: A consensus report from an international seminar on nomenclature and classification, convened by the WHO Collaborating Centre for Oral Cancer

Oral potentially malignant disorders (OPMDs) are associated with an increased risk of occurrence of cancers of the lip or oral cavity. This paper presents an updated report on the nomenclature and the classification of OPMDs, based predominantly on their clinical features, following discussions by an expert group at a workshop held by the World Health Organization (WHO) Collaborating Centre for Oral Cancer in the UK. The first workshop held in London in 2005 considered a wide spectrum of disorders under the term "potentially malignant disorders of the oral mucosa" (PMD) (now referred to as oral potentially malignant disorders: OPMD) including leukoplakia, erythroplakia, proliferative verrucous leukoplakia, oral lichen planus, oral submucous fibrosis, palatal lesions in reverse smokers, lupus erythematosus, epidermolysis bullosa, and dyskeratosis congenita. Any new evidence published in the intervening period was considered to make essential changes to the 2007 classification. In the current update, most entities were retained with minor changes to their definition. There is sufficient evidence for an increased risk of oral cancer among patients diagnosed with "oral lichenoid lesions" and among those diagnosed with oral manifestations of 'chronic graft-versus-host disease'. These have now been added to the list of OPMDs. There is, to date, insufficient evidence concerning the malignant potential of chronic hyperplastic candidosis and of oral exophytic verrucous hyperplasia to consider these conditions as OPMDs. Furthermore, due to lack of clear evidence of an OPMD in epidermolysis bullosa this was moved to the category with limited evidence. We recommend the establishment of a global research consortium to further study the natural history of OPMDs based on the classification and nomenclature proposed here. This will require multi-center longitudinal studies with uniform diagnostic criteria to improve the identification and cancer risk stratification of patients with OPMDs, link them to evidence-based interventions, with a goal to facilitate the prevention and management of lip and oral cavity cancer.

Oral verruciform xanthoma and erythroplakia associated with chronic graft-versus-host disease: a rare case report and review of the literature

BACKGROUND

Oral verruciform xanthoma is an uncommon benign lesion. Although oral verruciform xanthoma occurs in healthy individuals, it has been also reported in association with some inflammatory conditions. The aim of this study is to report a case of oral verruciform xanthoma associated with chronic graft-versus-host disease and to review the literature on this topic.

CASE PRESENTATION

A 47-year-old Caucasian male presented to the Sector of Oral Medicine "V. Margiotta", University Policlinic "P. Giaccone" of Palermo complaining of a mass on the gingiva. He first noticed the painless mass 1 year ago. He reported to have undergone allogenic hematopoietic stem cell transplantation 15 years ago for acute lymphoblastic leukaemia. Intraoral examination revealed a well-circumscribed, sessile yellowish and verrucous nodule upon canine, multiple yellowish and verrucous nodules on the hard palate, yellowish and verrucous nodules on left buccal mucosa. In addiction an area of white striae in a reticular pattern with erythema and ulceration was present on the dorsum of the tongue. This lesion was consistent with a known history of oral chronic graft versus host disease. Moreover, we observed a suspected area of oral erythroplakia yet on the dorsum of the tongue. In biopsy specimen of hard palate histopathological examination revealed a diagnosis of verrucous xanthoma of the oral cavity; in addiction in biopsy specimen of the dorsum of the tongue revealed the presence of erythroplakia with high grade dysplasia.

CONCLUSION

Verruciform xanthoma of the oral cavity associated with chronic graft-versus-host disease is a rare condition with a usually benign clinical course but malignant transformation has been described in association with oral potential malignant disorder (e.g. chronic graft versus host disease, erythroplakia). Very rare cases showed association with oral chronic graft versus-host-disease. To date, only eight cases were published in the world literature. Therefore it could be important follow up patients also for oral verruciform xanthoma onset.

Diagnosis and Clinical Management of Human Papilloma Virus-Related Gingival Squamous Cell Carcinoma in a Patient With Leukemia: A Case Report

Introduction

Close clinical inspection for intraoral lesions in patients with leukemia that develop chronic graft-versus-host disease (cGVHD) is critical. Additionally, neoplasias developing in bone marrow transplant patients after treatment for leukemia represent a significant obstacle for long-term patient survival, necessitating lifetime follow-up by health care providers. This case report describes the identification, diagnosis, and treatment of gingival squamous cell carcinoma (SCC) in a patient with leukemia who was treated previously with a stem cell transplant and referred for routine periodontal care.

Case Presentation

A 53-year-old male was referred to the Department of Periodontics for an assessment of tooth #10 with 2+ mobility and associated cross-bite occlusion. The patient was diagnosed with acute myeloid leukemia at age 39 years, received hematopoietic stem cell transplantation (HSCT), and later developed cGVHD followed by human papilloma virus (HPV) infections. During the periodontal evaluation, a large, non-painful, exophytic, alveolar gingival mass was identified and later diagnosed as SCC. It is unusual that oral SCC presents as an exophytic, gingival swelling. The patient received comprehensive periodontal management in coordination with his otolaryngology team before and during the diagnosis of SCC secondary to cGVHD and HPV infection.

Conclusions

Patients with a history of HSCT treatment for leukemia and subsequent cGVHD are at a high risk of developing second primary oral malignancies, including SCC. Exposure to oncogenic HPV infection may compound this risk. Therefore, it is important for dentists to be aware of special treatment concerns and to frequently screen these patients to achieve early diagnosis and treatment of these neoplasms.

Dental treatment in patients with leukemia

Dental treatment of patients with leukemia should be planned on the basis of antineoplastic therapy which can be chemotherapy with or without radiotherapy and bone marrow transplantation. Many are the oral manifestations presented by these patients, arising from leukemia and/or treatment. In addition, performing dental procedures at different stages of treatment (before, during, or after) must follow certain protocols in relation to the haematological indices of patients, aimed at maintaining health and contributing to the effectiveness of the results of antineoplastic therapy. Through a literature review, the purpose of this study was to report the hematological abnormalities present in patients with leukemia, trying to correlate them with the feasibility of dental treatment at different stages of the disease. It is concluded in this paper that dental treatment in relation to haematological indices presented by patients with leukemia must follow certain protocols, mainly related to neutrophil and platelet counts, and the presence of the dentist in a multidisciplinary team is required for the health care of this patient.

Oral potentially malignant disorders: an overview of more than 20 entities

Cancer of the oral cavity accounts for approximately 3% of all malignancies diagnosed annually in 270,000 patients world-wide. Oral cancer is the 12th most common cancer in women and the 6th in men. Many oral squamous cell carcinomas develop from potentially malignant disorders (PMDs). Lack of awareness about the signs and symptoms of oralPMDs in the general population and even healthcare providers is believed to be responsible for the diagnostic delay of these entities. The aim of this article is to update and improve the knowledge of healthcare providers about oral PMDs.

Orofacial diseases in solid organ and hematopoietic stem cell transplant recipients

OBJECTIVE

Solid organ transplant (SOT) and hematopoietic stem cell transplant (HSCT) recipients are at risk of several diseases, principally attributable to immunosuppression. This global overview of SOT/HSCT-associated orofacial diseases is aimed at providing a practical instrument for the oral healthcare management of SOT/HSCT recipients.

METHODS

Literature search was made through MEDLINE. The associations between orofacial diseases and SOT/HSCT were assessed using observational studies and case series and were classified into 'association', 'no association', and 'unclear association'.

RESULTS

Lip/oral cancers, drug-induced gingival overgrowth (DIGO), infections, including hairy leukoplakia and, less frequently, post-transplantation lymphoproliferative disorders (PTLDs) and oral lichenoid lesions of graft-versus-host disease (GVHD), were associated with SOT. Lip/oral cancers, GVHD, mucositis, DIGO, infections and, less frequently, PTLDs were associated with HSCT. Associations of orofacial granulomatosis-like lesions and oral mucosa-associated lymphoid tissue-type lymphoma with SOT, and of pyogenic granuloma and hairy leukoplakia with HSCT were unclear. Periodontal disease and dental caries were not associated with SOT/HSCT. For none of the local treatments was there a strong evidence of effectiveness.

CONCLUSIONS

Solid organ transplant/HSCT recipients are at risk of orofacial diseases. Adequate management of these patients alleviates local symptoms responsible for impaired eating, helps prevent systemic and lethal complications, and helps where dental healthcare has been neglected.

Multiple squamous cell carcinomas of the oral cavity in a young patient with graft-versus-host disease following allogenic bone marrow transplantation

The development of secondary malignancies is a potential long-term complication after haematopoietic stem cell transplantation (HSCT). In particular, a higher incidence of oral squamous cell carcinoma (OSCC) has been reported in patients experiencing chronic graft versus host disease (cGvHD) secondary to HSCT. This report describes the development of two synchronous SCC of the buccal mucosa in a young female patient treated with HSCT for beta thalassemia major. She had undergone HSCT at the age of 9 years and developed oral GvHD 6 months after transplant. 17 years after HSCT she developed two synchronous carcinomatous lesions on the tongue and floor of the mouth. The current case highlights the association between oral cGvHD and OSCC, and the possible development of OSCC in young patients even many years after HSCT. This evidence suggests closer follow-up for all patients treated with HSCT who developed cGvHD, and more effective strategies to prevent and treat cGvHD.

A case of tongue carcinoma associated with chronic graft-versus-host disease after allogeneic haematopoietic stem cell transplantation

Graft-versus-host disease (GVHD) can occur at various sites, including the oral mucosa, where it is associated with a high risk of head and neck cancer. We report the case of a 46-year-old woman with tongue cancer that developed following Hodgkin's lymphoma and chronic GVHD, and we discuss the possible causes of cancer development.

Pathophysiology, etiologic factors, and clinical management of oral lichen planus, part I: facts and controversies

Lichen planus (LP) is an inflammatory disease of the stratified squamous epithelia of unknown etiology. LP affects most frequently the oral mucosa, but it may also involve other mucosa and the skin. Oral LP (OLP) most frequently affects woman aged between 30 and 60 years. Histopathologic examination typically shows orthokeratotic hyperkeratosis, basal cell degeneration, and a dense well-defined infiltrate of lymphocytes in the superficial dermis. OLP lesions may result from the induction of keratinocytes apoptosis by cytotoxic CD8+ T cells stimulated by a yet unidentified self-antigen on a genetically predisposed patient. The association of OLP with hepatitis C virus (HCV) has been more consistently demonstrated in the Mediterranean area. Although HCV RNA and HCV-specific CD4+ and CD8+ T cells have been retrieved in the mucosal lesions of patients with chronic HCV infection and OLP, the eventual pathophysiology of HCV in OLP lesions remains unclear. Available treatments of OLP are not curative, and many have potentially prominent side effects. The objectives of OLP management should be to prevent and screen for malignant transformation and alleviate symptoms on the long-term. Avoidance of potential precipitating drugs, tobacco, alcohol, and local trauma, as well as strict oral hygiene, is essential. The first-line pharmacologic treatment relies on topical steroids. Systemic steroids should be limited to the short-term cure of severe refractory OLP. Life-long clinical follow-up, at least annually, is fundamental.

Oral carcinoma after hematopoietic stem cell transplantation--a new classification based on a literature review over 30 years

Background

Patients undergoing hematopoietic stem cell transplantation (HSCT) have a higher risk of developing secondary solid tumors, in particular squamous cell carcinoma, because of several risk factors, including full-body irradiation (TBI), chemotherapy, and chronic graft versus host disease (GVHD). Based on the review presented here, a classification of oral changes is suggested in order to provide a tool to detect high-risk patients.

Methods and Results

The literature over the last 30 years was reviewed for development of malignoma of the oral cavity after HSCT. Overall, 64 cases were found. In 16 out of 30 cases, the tongue was the primary location, followed by the salivary gland (10 out of 30); 56.4% appeared in a latency time of 5 to 9 years after HSCT. In 76.6%, GVHD was noticed before the occurrence of oral malignancy. Premalignant changes of the oral mucosa were mucositis, xerostomia, and lichenoid changes, developing into erosive form.

Conclusion

All physicians involved in the treatment of post-HSCT patients should be aware of the increased risk, even after 5 years from the development of oral malignancy, in particular when oral graft versus host changes are visible. In order to develop evidence based management, screening and offer adequate therapy as early as possible in this patient group, multicenter studies, involving oncologists and head and neck surgeons, should be established.

Squamous cell carcinoma of the buccal mucosa in a young adult with history of allogeneic bone marrow transplantation for childhood acute leukemia

BACKGROUND

Secondary cancers are severe complications in patients who have had allogeneic bone marrow transplantation for childhood leukemia. We describe here a case of squamous cell carcinoma (SCC) of the buccal mucosa in a young adult patient who had had allogeneic bone marrow transplantation for childhood acute leukemia.

METHODS AND RESULTS

The primary tumor was treated with interstitial brachytherapy, and lymph node metastasis was treated by supraomohyoid neck dissection. The patient had a history of acute lymphoblastic leukemia (ALL) at 11 years of age and had received an allogeneic bone marrow transplant from a female donor. Further investigation of the tissue specimens by fluorescent in situ hybridization (FISH) revealed that an XX chromosome pattern was dominant in the tumor region, and this suggested that donor-derived cells might affect carcinogenesis in the recipient.

CONCLUSIONS

This case presents an incidence of secondary oral cancer associated with allogeneic bone marrow transplantation.

Oral mucosal disease: Lichen planus

Lichen planus (LP) is a common disorder in which auto-cytotoxic T lymphocytes trigger apoptosis of epithelial cells leading to chronic inflammation. Oral LP (OLP) can be a source of severe morbidity and has a small potential to be malignant. The diagnosis of OLP can be made from the clinical features if they are sufficiently characteristic, particularly if typical skin or other lesions are present, but biopsy is recommended to confirm the diagnosis and to exclude dysplasia and malignancy. OLP is treated with anti-inflammatory agents, mainly the topical corticosteroids, but newer agents and techniques are becoming available.

Dental management of patients with bone marrow and solid organ transplantation

With advances in transplant science, an increasing number of people are undergoing and surviving hematopoietic stem cell and solid organ transplantation. Those transplant recipients are also living longer. This means that many dentists nowadays will occasionally treat patients who are anticipating or who have received a transplant. Dentists thus should be knowledgeable about issues related to this population. The dentist's role is important because transplant patients are especially vulnerable to infection, which can stem from poor oral and dental hygiene. This article provides dentists with an overview of transplant science and guidance for dentists treating transplant patients.

Cyclosporin-induced downregulation of the expression of E-cadherin during proliferation of edentulous gingival epithelium in rats

BACKGROUND

To examine the role of E-cadherin in epithelial hyperplasia of cyclosporin A (CsA)-induced gingival enlargement, mRNA and protein levels of E-cadherin, beta-catenin, proliferating cell nuclear antigen (PCNA), and Cyclin D1 were examined in the edentulous gingiva of rats following CsA treatment.

METHODS

Three weeks after the extraction of all maxillary molars, 20 male Sprague-Dawley rats were assigned to a CsA-fed group (30 mg/kg daily) or a control group. Five rats per group were sacrificed at weeks 1 and 4. Edentulous ridge specimens were taken, and the expression levels of E-cadherin, beta-catenin, Cyclin D1, and PCNA mRNAs were estimated by reverse transcription-polymerase chain reaction (RT-PCR). Tissue specimens of the week 4 groups were examined using immunohistochemical (IHC) staining for proteins.

RESULTS

The mRNA expression of E-cadherin was significantly weaker in the CsA-treated group than the control group at both times. Using IHC staining, a weaker level of membrane-bonded E-cadherin was also observed in the gingival epithelial cells in the CsA group than in controls. By contrast, significantly stronger beta-catenin and Cyclin D1 mRNA expressions and protein levels were found in CsA-treated rats than controls by RT-PCR and immunohistochemistry at week 4, whereas PCNA production was stronger at both times.

CONCLUSIONS

CsA treatment reduced the production of E-cadherin but increased the production of beta-catenin, Cyclin D1, and PCNA. Thus, CsA may downregulate E-cadherin gene expression, leading to the epithelial cell proliferation of gingival overgrowth.