Oral healthcare attendance and the effectiveness of referrals for rural antenatal women.

OBJECTIVES: To analyse the effectiveness of targeted stakeholder engagement strategies and the impact they have on antenatal referrals, oral health admission, attendance and education of pregnant women in a rural public dental clinic. METHOD: Key stakeholders (obstetric trained general practitioners [GPs] and midwives) were educated and motivated to refer pregnant women to the rural public dental clinic via priority referral pathways. A 10-month pre- and post-intervention period of oral health assessments and treatments was compared and contrasted. DESIGN: Quasi-experimental study. SETTING: A rural health service in the Loddon Mallee region, Victoria. PARTICIPANTS: Local pregnant women, 18 years of age or older, eligible for public dental care. MAIN OUTCOME MEASURES: Increased oral health admission, attendance and education of pregnant women. RESULTS: Active engagement with key stakeholders significantly increased the oral health referral, admission and attendance of eligible antenatal women. Prior to the intervention, only 15.04% of eligible antenatal women sought oral health treatment, in comparison with 40.37% post-intervention. Of the 62 women referred, 44 actively received dental care. CONCLUSION: Active engagement with key stakeholders has demonstrated a clinically effective method of increasing antenatal referrals of socially disadvantaged women to a rural public dental clinic. Further collaboration between healthcare professionals can improve the oral health admission rates, attendance and education of antenatal women and their children.

Inhibition of matrix metalloproteinase-2 modulates malignant behaviour of oral squamous cell carcinoma cells.

BACKGROUND: Matrix metalloproteinases (MMPs) play a crucial role in the malignant phenotype of cancer cells. In particular, active levels of MMP2 in cancer cells have been associated with invasion and metastasis through the degradation of basement membrane extracellular matrix proteins. However, little is known about the role of this potential biomarker in oral cancer. Our aim was to investigate the effect of MMP2 inhibition on OSCC activity in vitro, as well as to assess MMP2 dysregulation in oral cancer samples. METHODS: Human OSCC cell lines H357 and H400 were tested with the selective MMP2 inhibitor ARP101 and the MMP2 neutralising monoclonal antibody MA5-13590 to assess cell proliferation in vitro using MTS assay. Cell migration at 12/24 h was assessed using a Transwell migration assay. Cell invasion was assessed at 24 h using a Corning Matrigel invasion assay. MMP2 expression was assessed in 208 tissue samples (related to 60 OSCC cases and nine normal control) using tissue microarray (TMA) and further analysed via TCGA. RESULTS: Both ARP101 and MA5-13590 monoclonal antibody reduced cell proliferation in both the cell lines tested. Treatment with 4µg/mL of MMP2 monoclonal antibody showed a significant decrease in cell migration at 24 hours. The administration of ARP101 and monoclonal antibody to H357 and H400 cell lines induced a drastic reduction in cell invasion at 24 h compared to the control. In patients, TCGA analysis demonstrated that oral cancer tissues express significantly higher levels of MMP2 mRNA compared to normal oral tissues. Further, IHC analysis on TMA showed significant difference in MMP2 protein expression between low and high histopathological grade OSCC. CONCLUSIONS: We have demonstrated, for the first time, that MMP2 inhibition affects oral cancer cells ability to survive, migrate and invade in vitro. Differences between MMP2 expression in normal and malignant tissues varied. Further research on the role of MMP2 in OSCC and novel mechanisms to inhibit MMP2-dependent pathways should be encouraged.

Expression Profile of Stemness Markers CD138, Nestin and Alpha-SMA in Ameloblastic Tumours.

Ameloblastic carcinoma is a rare malignant odontogenic neoplasm with a poor prognosis. It can arise de novo or from a pre-existing ameloblastoma. Research into stemness marker expression in ameloblastic tumours is lacking. This study aimed to explore the immunohistochemical expression of stemness markers nestin, CD138, and alpha-smooth muscle actin (alpha-SMA) for the characterisation of ameloblastic tumours. Six cases of ameloblastoma and four cases of ameloblastic carcinoma were assessed, including one case of ameloblastic carcinoma arising from desmoplastic ameloblastoma. In all tumour samples, CD138 was positive, whilst alpha-SMA was negative. Nestin was negative in all but one tumour sample. Conversely, the presence or absence of these markers varied in stroma samples. Nestin was observed in one ameloblastic carcinoma stroma sample, whilst CD138 was positive in one ameloblastoma case, one desmoplastic ameloblastoma case, and in two ameloblastic carcinoma stroma samples. Finally, alpha-SMA was found positive only in the desmoplastic ameloblastoma stroma sample. Our results suggest nestin expression to be an indicator for ameloblastic carcinoma, and CD138 and alpha-SMA to be promising biomarkers for the malignant transformation of ameloblastoma. Our data showed that nestin, CD138, and alpha-SMA are novel biomarkers for a better understanding of the origins and behaviour of ameloblastic tumours.

Kava constituents exert selective anticancer effects in oral squamous cell carcinoma cells in vitro.

Kava is a beverage made from the ground roots of the plant Piper Methysticum. Active compounds of Kava have previously been demonstrated to exert an antiproliferative effect through cell cycle arrest and promotion of apoptosis. Our aim was to investigate the in vitro effects of the main constituents derived from Kava on oral squamous cell carcinoma (OSCC) activity. Gas chromatography mass spectrometry (GCMS) was used to characterise the main constituents of two Kava preparations. Cell proliferation was assessed in two human OSCC cell lines (H400 and BICR56) and in normal oral keratinocytes (OKF6) treated with the identified Kava constituents, namely Flavokawain A (FKA), Flavokawain B (FKB), yangonin, kavain and methysticin using an MTS in vitro assay. Cell migration at 16 h was assessed using a Transwell migration assay. Cell invasion was measured at 22 h using a Matrigel assay. Cell adhesion was assessed at 90 min with a Cytoselect Adhesion assay. The two Kava preparations contained substantially different concentrations of the main chemical constituents. Treatment of malignant and normal oral keratinocyte cell lines with three of the identified constituents, 10 µg/ml FKA, 2.5 µg/ml FKB and 10 µg/ml yangonin, showed a significant reduction in cell proliferation in both H400 and BICR56 cancer cell lines but not in normal OKF6 cells. Remarkably, the same Kava constituents induced a significant reduction of OSCC cell migration and invasion. We have demonstrated, for the first time, that Kava constituents, FKA, FKB and yangonin have potential anticancer effects on OSCC. This highlights an avenue for further research of Kava constituents in the development of future cancer therapies to prevent and treat OSCC.

Protective effect of kava constituents in an in vitro model of oral mucositis.

PURPOSE: Oral mucositis is a debilitating inflammatory disorder observed in patients undergoing active cancer treatment, particularly cancer of the head and neck region. A key pathway believed to be involved in the pathogenesis of oral mucositis is the formation of reactive oxygen species (ROS). The identification of compounds that can inhibit this pathway may therefore be of benefit in treating this disorder. The kava plant (Piper methysticum) contains various constituents, including flavokawain A (FKA), flavokawain B (FKB), yangonin, methysticin and kavain. These constituents are known to be biologically active and possess anti-oxidative properties. This study therefore focused on examining these constituents for their effect on ROS formation in an in vitro oral mucositis model. METHODS: Cell proliferation was assessed in normal oral keratinocytes (OKF6) treated with and without kava constituents, namely FKA, FKB, yangonin, methysticin and kavain using an MTS in vitro assay. Oxidative stress was assessed by co-treating and pre-treating OKF6 cells with H2O2. The effects were quantified by analysis of ROS production, using a CM-H2DCFDA assay. RESULTS: Pre-treatment of cells for 24 h with 2.5 µg/ml kavain and 5 µg/ml FKA demonstrated a significant protective anti-oxidative effect. Similarly, FKB at a concentration of 2.5 µg/ml, demonstrated a trend of ROS reduction but was observed to be cytotoxic at concentrations greater than 5 µg/ml. Reduction in ROS production by methysticin and yangonin was compromised by their cell cytotoxicity. CONCLUSION: This was the first study to identify the anti-oxidative effects and safety of FKA and kavain with regard to oral keratinocytes, highlighting their potential use in the development of a preventative treatment for oral mucositis.

c-Myb Regulates the T-Bet-Dependent Differentiation Program in B Cells to Coordinate Antibody Responses.

Humoral immune responses are tailored to the invading pathogen through regulation of key transcription factors and their networks. This is critical to establishing effective antibody-mediated responses, yet it is unknown how B cells integrate pathogen-induced signals to drive or suppress transcriptional programs specialized for each class of pathogen. Here, we detail the key role of the transcription factor c-Myb in regulating the T-bet-mediated anti-viral program. Deletion of c-Myb in mature B cells significantly increased serum IgG2c and CXCR3 expression by upregulating T-bet, normally suppressed during Th2-cell-mediated responses. Enhanced expression of T-bet resulted in aberrant plasma cell differentiation within the germinal center, mediated by CXCR3 expression. These findings identify a dual role for c-Myb in limiting inappropriate effector responses while coordinating plasma cell differentiation with germinal center egress. Identifying such intrinsic regulators of specialized antibody responses can assist in vaccine design and therapeutic intervention in B-cell-mediated immune disorders.