Autophagy: a new concept in cancer research

Macroautophagy is a lysosomal catabolic process involved in recycling cell components and maintaining cellular homeostasis. Identifying some of the molecules involved in the control and execution steps of autophagy has shed light on the close link between autophagy and tumour progression. Several tumour-suppressor proteins -including Beclin 1, a protein involved in autophagosome formation- positively regulate autophagy. Conversely, some oncogenic proteins display inhibitory effects on autophagy. The antitumoral role of autophagy is supported by its involvement in reducing chromosome instability, proliferation and inflammation of tumour cells. However, autophagy can also be a protumoral mechanism which helps tumour cells to adapt to changes in their microenvironment (hypoxia, starvation...). Moreover, autophagy is induced in response to several anticancer treatments. This response can either be a mechanism allowing cell survival or a mechanism promoting cell death. The aim of this article is to summarize recent progress focusing on the dual role of autophagy in cancer.     

Human papillomavirus genotype detection from archival papanicolaou-stained cervical tests

BACKGROUND:

Archival Papanicolaou (Pap)‐stained cervical cytology tests may be the only source of a clinical sample for the evaluation of previous human papillomavirus (HPV) infection. Pap tests are ideal because the majority of women in countries with comprehensive screening programs would have had several collected and stored.

METHODS:

In the current study, HPV detection and genotyping were compared in samples collected from a conventionally fixed Pap test with those collected using an endocervical brush and collected in PreservCyt (liquid‐based) in 87 women undergoing management for a high‐grade Pap test abnormality. Cytology slides were scanned to create high‐resolution digital images before the removal of cells because the DNA extraction process resulted in the destruction of the cells from the original sample.

RESULTS:

All previously identified high‐grade abnormalities on the Pap tests were detectable on the digital images. β‐globin was detected in all extracted Pap tests, indicating the presence of recoverable, amplifiable DNA. A total of 62 (71.3%) and 59 (67.8%) tests were found to have high‐risk (HR) HPV detected on PreservCyt and fixed Pap test slides, respectively, with >87% concordance for the detection of HR HPV genotypes. Complete HPV genotyping concordance was observed in 62% and was partial in 26% of sample pairs, with very good agreement for HPV types 16 and 18 (κ = 0.850 and 0.903, respectively). Only 1 Pap test slide was found to be positive whereas the PreservCyt had no detectable HPV DNA, demonstrating a low false‐positive rate (1%).

CONCLUSIONS:

The results of the current study confirm that imaging and subsequent HPV detection and genotyping in archival cervical smears can offer accuracy in HPV detection that is comparable to endocervical brush‐collected PreservCyt samples. Cancer (Cancer Cytopathol) 2010;. © 2010 American Cancer Society.     

Efficacy of stereotactic radiosurgery for radiation-induced meningiomas

Journal of Neuro-Oncology - Stereotactic radiosurgery is an established treatment option for sporadic meningiomas, though limited data exists for radiation-induced lesions. Patients treated with...     

Medulloepithelioma masquerading as chronic anterior granulomatous uveitis

CASE REPORT: We report a rare clinical case of unilateral ciliary body teratoid medulloepithelioma presented first with infantile cataract, subsequently masquerading as chronic granulomatous anterior uveitis, followed by appearance of a tumour over the iris surface. COMMENTS: Diagnosis of the tumour in the early stages allows proper management and avoids enucleation.     

Herpes simplex virus type 2 (HSV-2) infection in women attending an antenatal clinic in the South Pacific island nation of Vanuatu

OBJECTIVE: The objective of this study was to estimate the prevalence and correlates of herpes simplex virus type 2 infection in women in an antenatal clinic in the South Pacific island nation of Vanuatu. STUDY DESIGN: A prevalence survey of sexually transmitted infections of pregnant women attending an antenatal clinic at Vila Central Hospital was conducted in 1999-2000. Serum samples were tested for HSV-1 and HSV-2 antibodies by enzyme-linked immunosorbent assay. Results for other sexually transmitted infections and demographic and obstetric variables were analyzed for their association with HSV-2 serostatus. RESULTS: HSV-2 serum antibody results were obtained on 535 women and HSV-1 results on 134. The seroprevalence of HSV-2 was 30% and HSV-1 was 100%. On multivariate analysis, the independent predictors of HSV-2 infection were age, marital status, and trichomoniasis. CONCLUSIONS: HSV-2 was common in this sample of sexually active women in Vanuatu. This is the first study of HSV in Vanuatu and one of very few studies in the Pacific region.     

Biochemical abnormalities and excitotoxicity in Huntington's disease brain

The physiological role of huntingtin and the mechanisms by which the expanded CAG repeat in ITI5 and its polyglutamine stretch in mutant huntingtin induce Huntington's disease (HD) are unknown. Several techniques have now demonstrated abnormal metabolism in HD brain; direct measurement of respiratory chain enzyme activities has shown severe deficiency of complex II/III and a milder defect of complex IV. We confirm that these abnormalities appear to be confined to the striatum within the HD brain. Analysis of complex II/III activity in HD fibroblasts was normal, despite expression of mutant huntingtin. Although glyceraldehyde 3-phosphate dehydrogenase (a huntingtin binding protein) activity was normal in all areas studied, aconitase activity was decreased to 8% in HD caudate, 27% in putamen, and 52% in cerebral cortex, but normal in HD cerebellum and fibroblasts. We have demonstrated that although complexes II and III are those parts of the respiratory chain most vulnerable to inhibition in the presence of a nitric oxide (NO^•) generator, aconitase activity was even more sensitive to inhibition. The pattern of these enzyme deficiencies and their parallel to the anatomical distribution of HD pathology support an important role for NO^• and excitotoxicity in HD pathogenesis. Furthermore, based on the biochemical defects we have described, we suggest that NO^• generation produces a graded response, with aconitase inhibition followed by complex II/III inhibition and the initiation of a self-amplifying cycle of free radical generation and aconitase inhibition, which results in severe ATP depletion. We propose that these events are important in determining neuronal cell death and are critical steps in the pathogenesis of HD. Ann Neurol 1999;45:25–32     

Facile preparation and characterization of a novel visible-light-responsive Rb2HgI4 nanostructure photocatalyst

Visible photocatalytic procedures exhibit encouraging potential in water purification by increasing the photocatalytic performance. Therefore, the improvement of low-cost and efficient photocatalysts for environmental remediation is an increasing demand, and photocatalysts based on semiconductors have gained considerable attention due to their superior stability and activity. In the current study, novel Rb₂HgI₄ nanostructures were prepared via a simple, low-cost, and low-temperature solid-state method. The effects of different parameters such as type of surfactants, reaction temperature, and reaction time were studied on the structure, crystallinity, particle size, and shape of nanostructures. This new compound has a suitable band gap (2.6 eV) in the visible region. The photocatalytic performance of Rb₂HgI₄ was examined for the removal of coloring agents under visible light irradiation and it was found that this compound could degrade and eliminate acid black 1 by about 72.1%.

In this study, we reported Rb₂HgI₄ nanostructures as a new and efficient photocatalyst for the first time. We used the solid-state method for the fabrication of this compound at a low temperature.     

A Meta-Analysis for Association of XRCC3 rs861539, MTHFR rs1801133, IL-6 rs1800795, IL-12B rs3212227, TNF-α rs1800629, and TLR9 rs352140 Polymorphisms with Susceptibility to Cervical Carcinoma

Background:In spite of substantial declines in both incidence and mortality rates in the past 50 years, cervical cancer remains one of the leading causes of cancer associated mortality among women globally. We performed this meta-analysis to explore the role of XRCC3 rs861539, MTHFR rs1801133, IL-6 rs1800795, IL-12B rs3212227, TNF-α rs1800629 and TLR9 rs352140 polymorphism with susceptibility to cervical carcinoma. Methods:The search databases include PubMed, SciELO, MedRxiv, Web of Science, Scopus, Cochrane Library, China National Knowledge Infrastructure, and China Biology Medicine disc up to 30 June 2021. The language is limited to English and Chinese. The comparison between the polymorphisms and cervical cancer was assessed using pooled odds ratio (OR) and 95% confidence interval (CI). The data are statistically analyzed by Comprehensive Meta-Analysis (CMA) 2.0 software. Results:A total of 59 studies including seven studies with 1,112 cases and 1,233 controls on XRCC3 rs861539, 14 studies with 2,694 cases and 3349 controls MTHFR rs1801133, four studies with 1,121 cases and 1,109 controls on IL-12B rs3212227, seven studies with 1,452 cases and 2,186 controls on IL-6 rs1800795, 20 studies with 4,781 cases and 4909 controls on TNF-α rs1800629, and seven studies with 1743 cases and 2292 controls on TLR9 rs352140 were included. There was a significant association between XRCC3 RS861539, TNF-α rs1800629, and IL-6 rs1800795 polymorphisms and an increased risk of cervical carcinoma in overall population. However, the MTHFR rs1801133, IL-12B rs3212227 and TLR9 rs352140 polymorphisms were not associated. Conclusion:The pooled analysis showed that XRCC3 RS861539, TNF-α rs1800629, and IL-6 rs1800795 were associated with cervical carcinoma susceptibility, but not MTHFR rs1801133, IL-12B rs3212227 and TLR9 rs352140 polymorphisms.Key Words: Cervical carcinoma, cervical cancer, meta-analysis, gene, polymorphism