HIV-related non-Hodgkin lymphomas affecting the oral cavity: a clinicopathologic study of 11 cases

Background: HIV-related non-Hodgkin lymphomas of the oral cavity are rare lesions with aggressive clinical behaviour. The aim of this study is to describe the clinicopathological features of a series of HIV-related oral non-Hodgkin lymphomas. Material and Methods: Eleven cases of oral lymphomas affecting HIV-positive patients were retrieved from 2012 to 2019. Clinicopathological features regarding age, sex, tumour location, clinical presentation, laboratory findings, disease stage and follow-up were obtained. Histologic, immunohistochemical and in situ hybridization for EBV detection were done for diagnosis confirmation. Overall survival was estimated by Kaplan–Meier curve. Results: Males predominated, with a mean age of 40.3 years-old. Maxilla and mandible were the mostly affected. Plasmablastic lymphoma and diffuse large B-cell lymphoma not otherwise specified (NOS) were the main histological types. Lesions presented as reddish ulcerated swellings, representing the first sign of AIDS in six cases. Stage IV were common (7 cases) and the mean HIV viral load was 10,557 copies/mL, with a mean of 266 CD4+ cells/mm3, 1,278 CD8+ cells/mm3 and a CD4+/CD8+ ratio of 0.26. Eight patients died of the disease (72.7%). Overall survival revealed that 78.2% of the patients died after 21 months of follow-up. Conclusions: HIV-related oral lymphomas present a poor prognosis usually diagnosed in advanced stages and in our series plasmablastic lymphoma was the most common subtype.(AU)

Oral Kaposi sarcoma development is associated with HIV viral load, CD4+ count and CD4+/CD8+ ratio / El desarrollo del sarcoma de Kaposi oral está asociado con carga viral de VIH, recuento de CD4+ y relación CD4+/CD8+

Background: Kaposi’s sarcoma (KS) is an uncommon, multifocal and angioproliferative lesion, which demon-strates a poor prognosis. The aim of the present research was to explore the association of HIV viral load, CD4+and CD8+ counts and the CD4+/CD8+ ratio on the risk of oral Kaposi’s sarcoma (KS) development.Material and Methods: A total of 62 patients were retrieved from March 2008 to October 2020 from the files oftwo oral pathology centres. Clinical, laboratory and follow-up data were retrieved from their medical files. Poissonregression was used to explore the role of history of immunosuppression and its association with oral KS develop-ment. A P-value <0.05 was considered significant.Results: Sixty-two patients were included in the present study (32 with oral KS and 30 with no presentation oflesions anywhere on the body). Patients with oral KS presented a mean age of 32.6 years, and male patients weremore affected. The hard palate (15 cases; 46.8%) was the main anatomical site affected. The lesions were mostlypresented as swellings (13 cases; 40.6%) and nodules (12 cases; 37.5%). Systemic manifestations were also ob-served, including candidiasis (4 cases; 12.5%), bacterial infection (3 cases; 9.3%), tuberculosis (3 cases; 9.3%),herpes simplex (3 cases; 9.3%) and pneumonia (3 cases; 9.3%). A significant correlation was observed betweenHIV viral load, CD4+ count and the CD4+/CD8+ ratio with oral KS development.Conclusions: HIV viral load, CD4+ count and the CD4+/CD8+ ratio are associated with oral KS development.(AU)

Protease-Activated Receptor Type 1 Activation Enhances Osteogenic Activity in Human Periodontal Ligament Stem Cells.

Protease-activated receptor 1 (PAR1) has been associated to tissue repair and bone healing. The aim of the present study was to evaluate the effect of PAR1 activation on the osteogenic activity of human periodontal ligament stem cells (PDLSCs). PDLSCs were cultured in the presence of PAR1-selective agonist peptide (100 nM), thrombin (0.1 U/mL), or PAR1 antagonist peptide (100 nM). Calcium deposits, calcium concentration (supernatant), alkaline phosphatase activity (ALP), cell proliferation, and gene (qPCR) and protein expression (ELISA assay) of osteogenic factors were assessed at 2, 7, and 14 days. PAR1 activation led to increased calcium deposits (p < 0.05), calcium concentration (p < 0.05), ALP activity (p < 0.05), and cell proliferation (p < 0.05). Further, PAR1 activation may increase gene and protein expression of Runx2 (p < 0.05) and OPG (p < 0.05). In conclusion, PAR1 activation increases osteogenic activity of PDLSCs, providing a possible new strategy for periodontal regenerative therapies.

Effects of Selective Versus Non-Selective COX-2 Inhibition on Experimental Periodontitis.

In the present study we compared the effects of the selective COX-2 inhibitor etoricoxib with those of the classical non-selective NSAID diclofenac on the inflammatory process and alveolar bone loss in an experimental model of periodontitis in rats. Ninety male Holtzman rats (250 g) were randomly sorted into four experimental groups: Sham+CMC and Ligature+CMC (control) groups which received 0.5% carboxymethylcellulose sodium (CMC) solution; Ligature+Diclofenac and Ligature+Etoricoxib groups which received Potassium Diclofenac and Etoricoxib, respectively, suspended in 0.5% CMC (10 mg/kg/day). At 7, 14 and 21 days after placing ligatures in the cervical region of both the lower right and left first molars, the animals were euthanized. At the end of each period, the mandibles were collected for radiographic examination of alveolar bone loss. In addition, alveolar bone and periodontal ligament tissue samples were collected for COX-2 expression analysis and gingival tissues were collected for measurement of PGE2 contents. Animals with ligature-induced periodontal disease showed significant increased COX-2 gene expression at days 7, 14 and 21 (p<0.05) on alveolar bone and periodontal ligament. However, both treatments resulted in significantly reduced alveolar bone loss when compared to the untreated Ligature group (p<0.05), with no statistical difference between Etoricoxib and Diclofenac Potassium groups. This study shows that both drugs were able to reduce alveolar bone loss after periodontal disease induction.