The role of control region mitochondrial DNA mutations in cardiovascular disease: stroke and myocardial infarction

Recent studies associated certain type of cardiovascular disease (CVD) with specific mitochondrial DNA (mtDNA) defects, mainly driven by the central role of mitochondria in cellular metabolism. Considering the importance of the control region (CR) on the regulation of the mtDNA gene expression, the aim of the present study was to investigate the role of mtDNA CR mutations in two CVDs: stroke and myocardial infarction (MI). MtDNA CR mutations (both fixed and in heteroplasmy) were analysed in two demographically-matched case-control samples, using 154 stroke cases, 211 MI cases and their corresponding control individuals. Significant differences were found, reporting mutations m.16145 G > A and m.16311 T > C as potential genetic risk factors for stroke (conditional logistic regression: p = 0.038 and p = 0.018, respectively), whereas the m.72 T > C, m.73 A > G and m.16356 T > C mutations could act as possible beneficial genetic factors for MI (conditional logistic regression: p = 0.001, p = 0.009 and p = 0.016, respectively). Furthermore, our findings also showed a high percentage of point heteroplasmy in MI controls (logistic regression: p = 0.046; OR = 0.209, 95% CI [0.045–0.972]). These results demonstrate the possible role of mtDNA mutations in the CR on the pathogenesis of stroke and MI, and show the importance of including this regulatory region in genetic association studies.This work was supported by MINECO (project: CGL2014-53781-r) and by Generalitat de Catalunya (Ref. 2017 SGR 1630). Postdoctoral fellowship SFRH/BPD/105660/2015 (AR) was supported by Fundação para a Ciência e a Tecnologia (FCT)

Tumorlets, multicentric carcinoids, lymph-nodal metastases, and long-term behavior in bronchial carcinoids.

Background: The clinical significance of lymph-node metastases, multicentric forms, and tumorlets in bronchial carcinoids is still a matter of debate. Aim of this study was to analyze their prevalence and clinical significance in a series of 123 bronchial carcinoids. Patients and Methods: Nodal dissection and serial sections of resected lung parenchima for research of multicentric forms and tumorlets were performed in most patients. Survival curve was produced using the Kaplan-Meyer method and multivariate analysis by the Cox proportional hazard model. Results: Lymph-node involvement was present in 14% of typical (14 of 100) and 13.04% of atypical carcinoids (3 of 23). Multicentric forms (syncronous carcinoids or tumorlets) were found in 11.3% of the total with a negative impact on survival (p = 0.021). Multiple tumorlets were found in 7.3% of all cases at the standard pathologic examination, but whenever accurate palpation and serial sections of the surgical specimen were performed, the percentage reached 24% of the cases. Overall survival was 98.2%, 95.8%, and 83.9% for typical and 71.6%, 57.3%, and 24% for atypical carcinoid respectively at 5, 10, and 15 years. Time from surgery was significantly directly correlated with recurrences (p < 0.0001) and disease related death (p = 0.0002). Conclusions: A high prevalence of tumorlets, multiple carcinoids, and lymph-nodal involvement was found in our series. On the basis of these observations bronchial carcinoids always require major surgical procedures with systematic nodal dissection, and a careful search for multifocal lesions should always be performed. Follow-up should always be accurate and protracted, due to the frequency of very long-term relapses (often more than 10 years after surgery). \ua9 2009 by the International Association for the Study of Lung Cance