Genomic evidence of SARS-CoV-2 reinfection cases in southern Brazil.

Cases of reinfection with severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) have been reported worldwide. We investigated reinfection cases in a set of more than 30,000 samples, and the SARS-CoV-2 genomes from selected samples from four patients with at least two positive diagnoses with an interval ≥ 45 days between tests were sequenced and analyzed. Comparative genomic and phylogenetic analysis confirmed three reinfection cases and suggested that the fourth one was caused by a virus of the same lineage. Viral sequencing is crucial for understanding the natural course of reinfections and for planning public health strategies for management of COVID-19.

The Relevance of Ultrastructural Studies of Metastatic Cells from Women with Breast Cancer History.

The interaction between cancer cells and the surrounding microenvironment is determinant for metastasis success. In this study, the ultrastructural relevance of cells in the malignant pleural effusion (MPE) of women with breast cancer history was investigated. In MPE, it is possible to observe single cells and clusters. Women whose MPE presents carcinomas in aggregates have a better prognosis when compared to cases in which metastatic single cells are found. Samples were collected via fine-needle aspiration puncture (US-FNA). Subsequent to the material preparation and ultrathin cuts, they were observed using light and transmission electron microscopy (LM/TEM). LM and TEM images served as a basis for the creation of a digital sculpture using ZBrush® software. Clusters exhibited structural stability, en route vesicles allowing exocytosis of electron-dense fibrous elements, and cytoplasmic protrusions contributing to migratory and invasive skills. Single cells presented different necrotic phenotypes and many displayed leukocyte-like characteristics. Cluster cooperative relationships seem to be related to a long-term permanence in MPE. The absence of a collaborative network presumably triggers a more aggressive behavior of single cells. Its putative fusion with leukocytes can maximize the efficiency for transendothelial migration, increasing chances of metastatic success and, unfortunately, reducing survival of women with recidivism.

Molecular markers associated with the outcome of tamoxifen treatment in estrogen receptor-positive breast cancer patients: scoping review and in silico analysis.

Tamoxifen (TMX) is used as adjuvant therapy for estrogen receptor-positive (ER+) breast cancer cases due to its affinity and inhibitory effects. However, about 30% of cases show drug resistance, resulting in recurrence and metastasis, the leading causes of death. A literature review can help to elucidate the main cellular processes involved in TMX resistance. A scoping review was performed to find clinical studies investigating the association of expression of molecular markers profiles with long-term outcomes in ER+ patients treated with TMX. In silico analysis was performed to assess the interrelationship among the selected markers, evaluating the joint involvement with the biological processes. Forty-five studies were selected according to the inclusion and exclusion criteria. After clustering and gene ontology analysis, 23 molecular markers were significantly associated, forming three clusters of strong correlation with cell cycle regulation, signal transduction of proliferative stimuli, and hormone response involved in morphogenesis and differentiation of mammary gland. Also, it was found that overexpression of markers in selected clusters is a significant indicator of poor overall survival. The proposed review offered a better understanding of independent data from the literature, revealing an integrative network of markers involved in cellular processes that could modulate the response of TMX. Analysis of these mechanisms and their molecular components could improve the effectiveness of TMX.

Follow-Up of Women with Cervical Cytological Abnormalities: Progression and Regression Events

Abnormalities in the cervix, when identified early by Pap smear, can be treated in the early stages or in the precursor stages of the neoplasia, which may increase the chances of regression of the lesion. The aim to verify the rate of cervical abnormalities and to evaluate the risk of progression or regression associated with age and cytological diagnosis. Methods: The study was conducted in a referral hospital in Southern Brazil, based on the results of pathology and cytopathology laboratory tests of uterine cervix. The historical cohort included patients with an abnormal cytology diagnosis in the period from January 2010 to December 2014, followed until July 2016. Results: A total of 42,389 cervical smears were analyzed, 4,427 of which were eligible for analysis of the evolution of cervical abnormalities. In progression and regression events analysis, we observed that patients with a cytological diagnosis of atypical glandular cells presented a higher risk of cervical abnormality progression (Hazard Ratio: 2.0 and 95% confidence intervals 1.36­3.48). We also observed that patients younger than 25 years old were more likely to regress the cervical lesions (Hazard Ratio:1.4 and 95% confidence intervals 1.20­1.74). Conclusions: The associations found between the events (progression and regression), age and cytological diagnosis, highlights the importance of cytological screening in populations at risk of precursor of cervical cancer lesions, especially in women older than 25 years.

Impact of Her-2 Overexpression on Survival of Patients with Metastatic Breast Cancer

Introduction: Breast cancer is a complex and heterogeneous disease which is increasingly important as a public health problem. In Brazil, 57,960 new cases have been estimated to be the burden in 2016 and 2017. Despite advances in early diagnosis and therapy, approximately 20-30% of patients, even with early stage lesions, will develop distant metastatic disease. Tumors with similar clinical and pathological presentations may have differing behavior, so it is important to understand specific biological characteristics. Objective: To investigate tumor markers of primary tumors featuring pleural metastasis to identify organ-specific characteristics of metastatic breast cancer. Methods: In a historical cohort study, immunohistochemistry was performed on cell blocks of neoplastic pleural effusions and results were compared with clinicopathological data. Results: The median survival time with Her-2 overexpression in malignant pleural effusions was 2.2 months, whereas cases without overexpression survived, on average, for seven months (p = 0.02). Conclusions: We emphasize that metastases may behave independently of primary tumors, but the present results indicate that therapeutic agents targeting Her-2 overexpression could increase survival in metastatic breast cancer cases.

Impact of cell arrangement of pleural effusion in survival of patients with breast cancer.

OBJECTIVE: This study was performed to evaluate the potential influence of cytological differences between pleural effusions on the survival of women with metastatic breast cancer during 30 months of follow-up. STUDY DESIGN: A hospital-based cohort study was performed. Pleural fluid cytology slides from patients with breast cancer were examined. Cases were grouped according to the pattern of tumor cells (spheroid and isolated), in order to access their prognostic value. RESULTS: The study comprised 87 patients. An isolated cell pattern was associated with higher mortality 30 months after the pleural effusion when compared to a spheroid pattern (p = 0.038). Patients with an isolated cell pattern showed higher risk of dying than patients with spheroid formations. The relative risk after adjustment of intervening variables was 5.336 (95% CI 1.054-27.020). The presence of a triple-negative immunohistochemical pattern significantly increased the risk of mortality before 30 months. CONCLUSION: Pleural effusion with isolated malignant cells is associated with worse prognosis after 30 months of follow-up.

The role of urine cytology for 'decoy cells' as a screening tool in renal transplant recipients.

OBJECTIVE: To determine the role of urine cytology for 'decoy cells' as a screening tool for polyomavirus type BK (BKV) infection in renal transplant recipients. STUDY DESIGN: This was a prospective cohort study of patients undergoing renal transplantation between 2006 and 2010. RESULTS: A total of 442 patients underwent urine cytology for decoy cells, 27.8% underwent 1 examination only and 72.2% more than one. Of the 1,713 examinations reviewed, 426 (24.9%) were positive and 785 (45.8%) were negative for 'decoy' cells, 380 (22.2%) showed degenerated tubular cells and 122 (7.1%) were unsatisfactory for analysis. Urine cytology was found to have a specificity of 68.5%, a sensitivity of 84.6%, a positive predictive value of 21.2%, a negative predictive value of 97.8% and an overall accuracy of 69.9%. The incidence of polyomavirus nephropathy among the patients investigated was 11.8%. Of the 442 patients, 32 (7.2%) had graft loss, which was attributed to BKV nephropathy in 2 (6.2% of the 32). CONCLUSIONS: Urine cytology is an effective screening method for monitoring renal transplant patients, with high sensitivity and a high negative predictive value, and can therefore be used routinely in the follow-up of renal transplant patients.

Evaluation of the expression of C-kit (CD117) in ependymomas and oligodendrogliomas.

C-kit is a proto-oncogene located on the long arm of chromosome 4. Its product, CD117, is a specific immunohistochemical (IHQ) marker that is associated with response to a potent tyrosine kinase inhibitor therapy with STI-571 (Gleevec®) in chronic myelogenous leukemia and GISTs. In our study, we aimed to evaluate the expression of CD117 in glial tumors as this finding may guide therapeutic approaches for these brain tumors. Ependymomas and oligodendrogliomas, in formalin fixed and paraffin embedded blocks were assayed for CD117 immunoreactivity using anti-c-kit (CD117, DAKO). GISTs were used as positive control. We observed immunoreactivity of CD117 protein in 25.5% of tumors in both histological types. In oligodendrogliomas, there was an association between older age at diagnosis and positivity for CD117 (P=0.039). In addition, we observed an association between higher tumor grade (grade III) and positivity for CD117 (P=0.007). No clinical association was observed in ependymomas (P>0.05). This study encourages further investigations, considering that CD117 may be a possible oncogenic factor in some glial tumors. In this case, tumors that express this marker may eventually benefit from a therapy with selective inhibitors of receptor kinases.