Glass fiber posts relining: can composite opacity influence retention to root canal dentin?

Odontology - This study aimed at evaluating the influence of glass-fiber post (GFP) relining with composites of different opacities on resin cement layer thickness (CLT), bond strength (BS) to root...     

Glutathione S-transferase Polymorphisms in Head and Neck Squamous Cell Carcinoma Treated with Chemotherapy and/or Radiotherapy

Background/Aim: The Glutathione S-transferases (GSTs) are important carcinogen-metabolizing enzymes. Polymorphisms involved in these enzymes can modulate the development and treatment of head and neck cancer. To investigate the association of GSTs polymorphisms with head and neck cancer and risk factors, clinical-pathological features, and survival time of the patients treated with chemotherapy and/or radiotherapy. Methods: The GST gene polymorphisms were evaluated in 197 cases and 514 controls by PCR-RFLP-Polymerase Chain Reaction Restriction Fragment Length Polymorphism. Results: The GSTP-313 was associated with a decreased risk for HNSCC (p=0.050). The GSTP1 haplotype analysis revealed a higher frequency of the AC and AT haplotypes in the case group than in the control group (p=0.013 and p=0.019, respectively), and the opposite for G-C haplotype (p = 0.015). Yet, the different combinations between the genotypes were associated with an increased risk of cancer. The study showed no association between the polymorphisms and primary tumor site, clinical-pathological characteristics, treatment (chemotherapy and/or radiotherapy) and survival time of the patients. Conclusion: The GST polymorphisms combination showed an increased risk for carcinogenesis, and studies with larger casuistry can contribute to the clarification of the role in individual patient differences for the response to chemotherapy and/or radiotherapy and identify biomarkers of susceptibility.     

Germline gain-of-function MMP11 variant results in an aggressive form of colorectal cancer

Matrix metalloproteinase-11 (MMP11) is an enzyme with proteolytic activity against matrix and nonmatrix proteins. Although most MMPs are secreted as inactive proenzymes and are later activated extracellularly, MMP11 is activated intracellularly by furin within the constitutive secretory pathway. It is a key factor in physiological tissue remodeling and its alteration may play an important role in the progression of epithelial malignancies and other diseases. TCGA colon and colorectal adenocarcinoma data showed that upregulation of MMP11 expression correlates with tumorigenesis and malignancy. Here, we provide evidence that a germline variant in the MMP11 gene (NM_005940: c.232C>T; p.(Pro78Ser)), identified by whole exome sequencing, can increase the tumorigenic properties of colorectal cancer (CRC) cells. P78S is located in the prodomain region, which is responsible for blocking MMP11's protease activity. This variant was detected in the proband and all the cancer-affected family members analyzed, while it was not detected in healthy relatives. In silico analyses predict that P78S could have an impact on the activation of the enzyme. Furthermore, our in vitro analyses show that the expression of P78S in HCT116 cells increases tumor cell invasion and proliferation. In summary, our results show that this variant could modify the structure of the MMP11 prodomain, producing a premature or uncontrolled activation of the enzyme that may contribute to an early CRC onset in these patients. The study of this gene in other CRC cases will provide further information about its role in CRC development, which might improve patient treatment in the future.