Treponema denticola chymotrypsin-like proteinase may contribute to orodigestive carcinogenesis through immunomodulation.

BACKGROUND: Periodontal pathogens have been linked to oral and gastrointestinal (orodigestive) carcinogenesis. However, the exact mechanisms remain unknown. Treponema denticola (Td) is associated with severe periodontitis, a chronic inflammatory disease leading to tooth loss. The anaerobic spirochete Td is an invasive bacteria due to its major virulence factor chymotrypsin-like proteinase. Here we aimed to investigate the presence of Td chymotrypsin-like proteinase (Td-CTLP) in major orodigestive tumours and to elucidate potential mechanisms for Td to contribute to carcinogenesis. METHODS: The presence of Td-CTLP within orodigestive tumour tissues was examined using immunohistochemistry. Oral, tonsillar, and oesophageal squamous cell carcinomas, alongside gastric, pancreatic, and colon adenocarcinomas were stained with a Td-CTLP-specific antibody. Gingival tissue from periodontitis patients served as positive controls. SDS-PAGE and immunoblot were used to analyse the immumodulatory activity of Td-CTLP in vitro. RESULTS: Td-CTLP was present in majority of orodigestive tumour samples. Td-CTLP was found to convert pro MMP-8 and -9 into their active forms. In addition, Td-CTLP was able to degrade the proteinase inhibitors TIMP-1, TIMP-2, and α-1-antichymotrypsin, as well as complement C1q. CONCLUSIONS: Because of its presence within tumours and regulatory activity on proteins critical for the regulation of tumour microenvironment and inflammation, the Td-CTLP may contribute to orodigestive carcinogenesis.

Treponema denticola chymotrypsin-like protease as associated with HPV-negative oropharyngeal squamous cell carcinoma.

BACKGROUND: An opportunistic oral pathogen, Treponema denticola (Td), has been linked to orodigestive carcinogenesis, but its role in oropharyngeal squamous cell carcinoma (OPSCC) has remained open. We evaluated the presence of Td chymotrypsin-like protease (Td-CTLP) in a series of 201 unselected consecutive OPSCC patients, and the relation of the Td-CTLP to human papillomavirus (HPV) status, to expression of toll-like receptors (TLR) 5, 7, and 9, and to clinical parameters and patient outcome. METHODS: Clinicopathological data came from hospital registries. The expression of cell surface-bound Td-CTLP was evaluated by immunohistochemistry. Immunoexpression of TLRs 5, 7, and 9, and HPV status we studied earlier in this patient series. RESULTS: We detected Td-CTLP in 81% of the OPSCC, and especially in HPV-negative tumours (48% of all OPSCCs). Among the HPV-positive tumours (52% of all OPSCCs), low Td-CTLP expression associated with low TLR 5 and high TLR 7 expression. Among those HPV-negative, higher TLR 5 and lower TLR 7 expression associated with high Td-CTLP expression. Strong Td-CTLP expression associated with poor disease-specific survival, but no similar association among HPV-positive and HPV-negative subgroups emerged. CONCLUSIONS: Td-CTLP was highly expressed in OPSCC and was associated with the HPV status of tumour tissue.

Treponema denticola chymotrypsin-like proteinase is present in early-stage mobile tongue squamous cell carcinoma and related to the clinicopathological features.

BACKGROUND: Certain periodontopathogenic bacteria have been linked to cancers. Treponema denticola (Td) is associated with severe periodontitis. Chymotrypsin-like proteinase (CTLP), a major virulence factor of Td, can degrade various host proteins and peptides, and modulate inflammatory responses. However, the role of Td in the tongue carcinogenesis remains unknown. This study aimed to investigate the presence of Td-CTLP in early-stage mobile tongue squamous cell carcinoma (MTSCC) and its relation to clinical and pathological characteristics. METHODS: The immunopositivity of Td-CTLP was assessed in samples obtained from 60 patients with MTSCC and associated with their clinicopathological data. Additionally, Td-CTLP expression was compared with immunoexpression of matrix metalloproteinases (MMP-8 and MMP-9), toll-like receptors (TLR-2, TLR-4, TLR-7 and TLR-9), c-Myc, Ki-67, Bmi-1 and Snail. RESULTS: Treponema denticola-chymotrypsin-like proteinase was present in 95% of MTSCC tumours of which many (40.4%) showed high immunopositivity. Td-CTLP positivity was significantly associated with invasion depth, tumour diameter and the expression of TLR-7, TLR-9 and c-Myc. High Td-CTLP immunopositivity in younger patients (≤ 60 years old) predicted early relapse. CONCLUSION: Our data indicate that Td and its CTLP are present in early-stage MTSCC carcinoma and may contribute to carcinogenesis, and therefore provide novel perspectives into intervention and therapeutic measures of MTSCC.

Altered Expression of Toll-like Receptors in Human Oral Epithelium in Oral Lichenoid Reactions.

Oral lichenoid reactions (OLRs) are chronic inflammatory lesions induced by contact with allergens. Toll-like receptors (TLRs) are members of pattern-recognition receptor superfamily. Once activated, TLRs induce production of cytokines and chemokines, thus leading to inflammatory reaction in host tissue. In the present study, we aimed to investigate the potential role of TLRs in the initiation and perpetuation of OLRs, in which TLRs induce innate immune responses mounted against allergens. TLRs, 1 through 10, were mapped in tissue samples obtained from healthy donors and OLR patients using real-time quantitative reverse transcription polymerase chain reaction, immunostaining, and image analyses. We found that the immunoreactivity for all TLRs was increased in OLRs, except for TLR5, which was noticeably reduced. Gene analysis revealed that TLR1, TLR2, TLR4, TLR7, TLR8, and TLR9 transcripts were upregulated in OLRs compared with controls. In contrast, expression of TLR3, TLR5, and TLR6 genes were negatively regulated in OLRs. TLR10 remained unchanged in both groups. In conclusion, TLRs expression is deranged in OLRs in which TLRs could be sensitized by allergens and haptens derived from dental restorations. TLR reactivity is further enhanced by recruitment of T lymphocytes forming a diffuse lymphocytic infiltrate and thus creating a proinflammatory loop cycle. These findings suggest that TLRs are involved in OLRs and pave the way for alternative cost-effective therapeutic intervention.

In Vivo Regulation of Active Matrix Metalloproteinase-8 (aMMP-8) in Periodontitis: From Transcriptomics to Real-Time Online Diagnostics and Treatment Monitoring.

BACKGROUND: This study investigated in vivo regulation and levels of active matrix metalloproteinase-8 (aMMP-8), a major collagenolytic protease, in periodontitis. METHODS: Twenty-seven adults with chronic periodontitis (CP) and 30 periodontally healthy controls (HC) were enrolled in immunohistochemistry and transcriptomics analytics in order to assess Treponema denticola (Td) dentilisin and MMP-8 immunoexpression, mRNA expression of MMP-8 and its regulators (IL-1ß, MMP-2, MMP-7, TIMP-1). Furthermore, the periodontal anti-infective treatment effect was monitored by four different MMP-8 assays (aMMP-8-IFMA, aMMP-8-Oralyzer, MMP-8-activity [RFU/minute], and total MMP-8 by ELISA) among 12 CP (compared to 25 HC). RESULTS: Immunohistochemistry revealed significantly more Td-dentilisin and MMP-8 immunoreactivities in CP vs. HC. Transcriptomics revealed significantly elevated IL-1ß and MMP-7 RNA expressions, and MMP-2 RNA was slightly reduced. No significant differences were recorded in the relatively low or barely detectable levels of MMP-8 mRNAs. Periodontal treatment significantly decreased all MMP-8 assay levels accompanied by the assessed clinical indices (periodontal probing depths, bleeding-on-probing, and visual plaque levels). However, active but not total MMP-8 levels persisted higher in CP than in periodontally healthy controls. CONCLUSION: In periodontal health, there are low aMMP-8 levels. The presence of Td-dentilisin in CP gingivae is associated with elevated aMMP-8 levels, potentially contributing to a higher risk of active periodontal tissue collagenolysis and progression of periodontitis. This can be detected by aMMP-8-specific assays and online/real-time aMMP-8 chair-side testing.

Histamine H4 receptor signalling in tongue cancer and its potential role in oral carcinogenesis - a short report.

PURPOSE: Recent reports indicate that histamine and its novel, high-affinity histamine H4 receptor (H4R) play a role in carcinogenesis, and thus H4R signalling has become a focus of increasing interest in the pathogenesis of many cancers. The roles of H4R in oral epithelial dysplasia (OED) and oral tongue squamous cell carcinoma (OTSCC) are unknown. The purpose of this study was to assess H4R expression in OTSCC patients and in OTSCC-derived cell lines. METHODS: Biopsies taken from OED, OTSCC and healthy oral mucosa were studied by immunostaining. Primary human oral keratinocytes (HOKs) and two OTSCC-derived cell lines (HSC-3 and SCC-25) were used for the in vitro studies. Quantitative real-time PCR was used to measure oncogene expression in the stimulated HOKs. RESULTS: We found that H4R-immunoreactivity was significantly reduced in the OED and OTSCC samples, especially in the samples with higher histopathological grades and noticeably increased mast cell counts. The presence of H4R in HSC-3 cells had clearly waned, in contrast to the HOKs. Gene expression data indicated that histamine-relevant inflammatory and environmental elements may participate in the regulation of oncogenes. CONCLUSIONS: Our results suggest an association between H4R and oral carcinogenesis. Furthermore, our findings raise a potential implication of histamine-mediated factors in the regulation of oncogenes, possibly via mast cells, as crucial components of the tumor microenvironment. The identification of new elements that govern oral cancer development is highly relevant for the development of novel therapeutic approaches in OTSCC.