Nádia Lago Costa

Tumor-associated macrophages and the profile of inflammatory cytokines in oral squamous cell carcinoma

OBJECTIVE To evaluate and characterize macrophage populations (M1/M2) in the tumor microenvironment of oral cavity squamous cell carcinoma (OCSCC). The relationship between macrophages and clinicopathological factors, such as survival data, lymph node metastasis, tumoral proliferation, and WHO histological grading are also analyzed. MATERIALS AND METHODS The samples consisted of surgically excised specimens from patients with non-metastatic and metastatic OCSCC and normal oral mucosa (control). Immunohistochemistry, flow cytometry, and qRT-PCR were used to evaluate macrophage populations and the expression of pro- (IL-12, IL-23, and INF-γ) and anti-inflammatory (IL-10 and TGF-β) cytokines. The level required for statistical significance was defined as p<0.05. RESULTS The data showed a predominance of M2 phenotype (high percentage of IL-10(+)TGF-β(+)) macrophages in the tumor microenvironment of OCSCC. A higher percentage of macrophages expressing TGF-β was seen in the OCSCC group when compared with healthy individuals. The assessment of mRNA expression also presented a greater expression of anti-inflammatory cytokines TGFβ and IL10 in OCSCC when compared with the control group. The percentage of macrophages, demonstrated by immunohistochemistry, was significantly higher in the metastatic OCSCC group than in the non-metastatic and control groups. The log-rank test also showed that the mean survival time for patients with high levels of macrophages was less (44 months) when compared with patients with a low percentage of such cells (93 months). CONCLUSION A predominance of the M2 phenotype in the tumor microenvironment of OCSCC could contribute to local immunosuppression, via TGF-β production, and consequently greater lymph node involvement and reduced patient survival time.

Differential infiltration of CD8+ and NK cells in lip and oral cavity squamous cell carcinoma.

BACKGROUND CD8+ and natural killer (NK) cells have been considered the most effective cells in the combat of cancer, contributing to better prognosis and longer survival. METHODS The aim of this study was to evaluate the population of CD8+ and NK cells, by immunohistochemistry, in samples of oral cavity squamous cell carcinoma (OCSCC) and lip squamous cell carcinoma (LSCC), leukoplakia, actinic cheilitis, and healthy oral mucosa (control). The relationship of CD8+ and NK cells with survival data, lymph node metastasis, tumor size, and proliferative index was also evaluated. RESULTS The number of peritumoral and intratumoral CD8+ and NK cells was significantly higher in LSCC, when compared with control, pre-malignant lesions, and OCSCC. A higher proportion of peritumoral CD8+ cells demonstrated correlation with a lower neoplastic proliferative index. Moreover, patients with OCSCC with a high density of peritumoral CD8+ cells showed a tendency towards a longer survival time. CONCLUSIONS The differential CD8+ and NK cells infiltration in oral SCC might reflect a distinctive tumor microenvironment with a favorable local cytotoxic immune response against neoplastic cells.

Distinctive clinical and microscopic features of squamous cell carcinoma of oral cavity and lip

OBJECTIVE This study was undertaken to gain insight into the distinctive features of squamous cell carcinoma of the lip (LSCC) and oral cavity (OCSCC). STUDY DESIGN A total of 37 cases of LSCC and 54 of OCSCC were compared regarding clinical and microscopic findings. RESULTS Predominance of head and neck TNM stages (HNTNM) T1-T2 in LSCC and T3-T4 in OCSCC was observed. A significant percentage (33.3%) of patients with OCSCC at HNTNM T1-T2 presented cervical lymph node metastasis and 18.75% died, whereas lymph node metastasis was absent and no patient died with LSCC at HNTNM T1-T2. LSCC demonstrated a higher number of cases with intense peritumoral inflammatory infiltrate compared with OCSCC. The analysis of the proliferative index demonstrated a significantly higher percentage of PCNA+ and Ki-67+ cells in OCSCC compared with LSCC. CONCLUSION Our results suggest that OCSCC and LSCC demonstrate distinct clinical and microscopic characteristics that reflect different biologic behavior and prognosis.

The clinicopathological significance of the expression of Granzyme B in oral squamous cell carcinoma

Granzyme B (GB) is a serine protease synthesized by activated cytotoxic T-lymphocytes and natural killer cells that induces neoplastic cells apoptosis. The expression of GB in the tumor microenvironment has been considered a favorable prognostic factor in several types of human cancers. Thus, the aim of this study was to evaluate the density of GB(+) cells in samples of oral cavity squamous cell carcinoma (OCSCC), as well as their relationship with clinical and microscopic parameters. GB expression was analyzed in 55 cases of OCSCC and metastatic and non-metastatic lymph nodes by means of immunohistochemistry. The high density of GB(+) cells demonstrated an association with the high percentage of Bax(+) and annexin V(+) neoplastic cells. In addition, the number of peritumoral GB(+) cells was significantly higher in the OCSCC group without lymph node metastasis, when compared with the metastatic OCSCC group. Moreover, patients with OCSCC with a high density of peritumoral GB(+) cells showed a longer survival time when compared with patients with a lower density of these cells. In lymph node tissues, the density of GB(+) cells was significantly higher in non-metastatic lymph nodes than in metastatic lymph nodes. Our findings suggest that the increased of expression of GB in the tumor microenvironment of OCSCC and in lymph nodes may have beneficial effect against neoplastic cells, contributing to apoptosis of these cells and increased survival of patients.

Midkine expression in oral squamous cell carcinoma and leukoplakia.

BACKGROUND Midkine (MK), a 13-kDa heparin-binding growth factor, is overexpressed in various human cancers. However, its role in the development and progression of oral cavity squamous cell carcinoma (OCSCC) is still unclear. Thus, the aim of this study was to evaluate the expression of MK in samples of OCSCC, leukoplakia, and healthy oral mucosa (control). METHODS Surgically excised specimens from patients with primary OCSCC (n = 28) were immunostained for MK, Ki-67, PCNA, p53, bcl-2, Bax, and CD31. Besides this, MK expression was also investigated in leukoplakia and normal oral mucosa. The relationship of MK(+) cells with clinical parameters (tumor location, tumor size, lymph node metastasis, and survival) and microscopic parameters (WHO histological grading, intensity of inflammation, proliferation index, apoptosis, and angiogenesis) was also evaluated. RESULTS The results showed that MK expression was increased in OCSCC in relation to leukoplakia and normal mucosa. Furthermore, MK expression was increased in late-stage tumors (T3/T4) compared with early-stage lesions (T1/T2). MK-positive lesions also showed increased expression of the anti-apoptotic protein bcl-2. CONCLUSION OCSCC, particularly late-stage tumors, exhibits increased MK expression, which may be involved in tumor progression via upregulation of anti-apoptotic genes, as shown by the augmented bcl-2 positivity in MK-positive tumors.

Distinct expression of perforin and granzyme B in lip and oral cavity squamous cell carcinoma

BACKGROUND Perforin and granzyme B (GB) are the main constituents of cytotoxic T-lymphocyte granules, and they have important roles in preventing the initiation and progression of cancer. METHODS The aim of this study was to compare the expression of CD8(+) /perforin(+) double-staining and GB(+) cells, by immunohistochemistry, in primary oral cavity squamous cell carcinoma (OCSCC), lip squamous cell carcinoma (LSCC), non-dysplastic leukoplakia (LK), dysplastic LK, actinic cheilitis (AC), oral lichen planus (LP) and normal oral mucosa. RESULTS Our results showed a higher expression of CD8(+) /perforin(+) and GB(+) cells in LSCC when compared with the samples of OCSCC, non-dysplastic and dysplastic LK, AC, oral LP and normal oral mucosa. In addition, increased CD8(+) /perforin(+) and GB(+) cell numbers were observed in all pre-malignant lesions (non-dysplastic LK, dysplastic LK, AC) when compared with the control. CONCLUSIONS Perforin and GB proteins may contribute to antitumoural immunity, leading to the direct killing of tumour cells; however, it seems to occur more effectively in LSCC than OCSCC.

Inflammatory response of human dental pulp to at-home and in-office tooth bleaching

ABSTRACT Tooth bleaching is a technique of choice to obtain a harmonious smile, but bleaching agents may damage the dental pulp. Objective: This study evaluated the inflammatory responses of human dental pulp after the use of two bleaching techniques. Material and Methods: Pulp samples were collected from human third molars extracted for orthodontic reasons and divided into three groups: control - no tooth bleaching (CG) (n=7); at-home bleaching with 15% carbamide peroxide (AH) (n = 10), and in-office bleaching with 38% hydrogen peroxide (IO) (n=12). Pulps were removed and stained with hematoxylin-eosin for microscopic analysis of inflammation intensity, collagen degradation, and pulp tissue organization. Immunohistochemistry was used to detect mast cells (tryptase+), blood vessels (CD31+), and macrophages (CD68+). Chi-square, Kruskal-Wallis, and Mann Whitney tests were used for statistical analysis. The level of significance was set at p<.05. Results: The inflammation intensity and the number of macrophages were significantly greater in IO than in AH and CG (p<0.05). The results of CD31+ (blood vessels per mm2) were similar in CG (61.39±20.03), AH (52.29±27.62), and IO (57.43±8.69) groups (p>0.05). No mast cells were found in the pulp samples analyzed. Conclusion: In-office bleaching with 38% hydrogen peroxide resulted in more intense inflammation, higher macrophages migration, and greater pulp damage then at-home bleaching with 15% carbamide peroxide, however, these bleaching techniques did not induce migration of mast cells and increased the number of blood vessels.

Overexpression of immunosuppressive cytokines is associated with poorer clinical stage of oral squamous cell carcinoma

OBJECTIVE The aim of this study was to evaluate the expression of IL-10 and TGF-β2 in oral squamous cell carcinoma (OSCC) and its relationship with prognostic clinical and microscopic parameters. DESIGN Immunohistochemistry was used to assess the expression of IL-10 and TGF-β2 in OSCC samples from 43 patients who had undergone surgical excision and neck dissection. Metastatic lymph nodes were included in the study (n=23). Samples of healthy oral mucosa (n=20) were used as controls. The sections were evaluated using a semi-quantitative method in conjunction with staining intensity. RESULTS Our findings showed that the expression of IL-10 and TGF-β2 by neoplastic and stromal cells was high in most of the OSCC samples (>70% of samples), especially when compared to the controls (≅10% of samples) (P<0.05). OSCC neoplastic cells in cervical lymph nodes were also positive for IL-10 and TGF-β2. An association between high expression of IL-10 by neoplastic cells and advanced clinical stage (T3-T4) was verified (P=0.02). Although not statistically significant, the expression of TGF-β2 was also augmented in advanced stage tumours. CONCLUSIONS These data suggest that the ability of OSCC neoplastic cells to secrete immunosuppressive cytokines could contribute to clinical progression by maintaining a microenvironment conducive to evasion and tumour proliferation.

Characterization of dendritic cells in lip and oral cavity squamous cell carcinoma.

BACKGROUND There may be differences in the antitumor immunity induced by dendritic cells (DCs) during the development of squamous cell carcinoma (SCC) located in the lip rather than in the oral cavity. The aim of this study was to evaluate the number of immature and mature DCs in SCC and potentially malignant disorders of the oral cavity and lip. METHODS Immunohistochemistry was used to identify the number (cells/mm(2) ) of immature (CD1a(+) ) or mature (CD83(+) ) DCs in samples of oral cavity SCC (OCSCC) (n = 39), lip SCC (LSCC) (n = 23), leukoplakia (LK) (n = 21), actinic cheilitis (AC) (n = 13), and normal mucosa of the oral cavity (OC control, n = 12) and the lip (lip control, n = 11). RESULTS The number of CD1a(+) cells tended to be higher in the OC control samples compared with the LK (P = 0.04) and OCSCC (P = 0.21). Unlike, this cell population was lower in the lip control than in AC or LSCC (P < 0.05). The number of CD83(+) cells was increased in the LSCC samples compared with the AC and lip control (P = 0.0001) and in OCSCC compared with both the LK (P = 0.001) and OC control (P = 0.0001) samples. LSCC showed an elevated number of CD1a(+) and CD83(+) cells compared with OCSCC (P = 0.03). The population of mature DCs was lower than the population of immature DCs in all of the tested groups (P < 0.05). CONCLUSION There were a greater number of both mature and immature DC populations in the LSCC samples than in the OCSCC, which could contribute to establishing a more effective immune antitumor response for this neoplasm.

Traumatic neuroma of the mandible: A case report with spontaneous remission

Traumatic neuroma is a well-known disorder involving peripheral nerves, which occurs following trauma or surgery. The lesion develops most commonly in the soft tissues of the mental foramen area, lower lip and tongue. Intra-osseous lesions arising in jawbones are very uncommon. In this paper, we report a new case of an intra-osseous traumatic neuroma, discovered incidentally on a panoramic radiograph obtained for orthodontic documentation. In addition, the case herein described developed spontaneous remission, a situation not previously reported in the literature. Finally, we discuss relevant demographic, clinical, microscopic, immunohistochemical and treatment aspects of traumatic neuromas. Key words:Amputation neuroma, traumatic neuroma, mandible, spontaneous remission.