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Objectives: To report the causative relationship of maternal COVID-19 with intrauterine fetal death, describe the specific placental pathology, findings of fetal autopsy and clinical characteristics, and identify potential risk factors.Methods: This is a prospective case series. A cohort of 165 placentas of non-vaccinated pregnant women affected by COVID-19 in Greece were histologically examined and six cases of intrauterine fetal death associated with SARS-COV-2 placentitis were retrieved. Complete fetal autopsy was performed in three cases. Gross, histopathological, immunohistochemical, molecular, and electron microscopy examinations were carried out in the stillbirth placentas and fetal organs. The histological findings of SARS-COV-2 placentitis were compared with the 159 cases, in which maternal COVID-19 resulted in livebirth. Regression analysis was used to identify predisposing factors for SARS-COV-2 placentitis.Results: All six stillbirth placentas showed severe and extensive histological changes of SARS-COV-2 placentitis, i.e. a combination of marked intervillositis with a mixed inflammatory infiltrate and massive perivillous fibrinoid deposition with trophoblast damage, associated with intensely positive immunostaining for SARS-COV-2 spike protein, the presence of virions on electron microscopy and a positive RT-PCR test in placental tissues. The histological lesions obliterated over 75% of the maternal intervillous space, accounting for intrauterine fetal death. Similar histological lesions affecting less than 25% of the placenta were recorded in 7 liveborn neonates, while the remaining 152 placentas of COVID-19-affected pregnancies with livebirths did not show similar findings. Complete fetal autopsy showed evidence of an asphyctic mode of death without evidence of viral transmission to the fetus. The mothers had mild clinical symptoms or were asymptomatic and the interval between maternal COVID-19 diagnosis and fetal death ranged from 3 to 15 days. Statistically significant predisposing factors for SARS-COV-2-placentitis included thrombophilia and IUGR. Multiple sclerosis was seen in one case.Conclusions: SARS-COV-2 placentits occurred uncommonly in COVID-19-affected pregnancies of non-vaccinated mothers and, when extensive, caused fetal demise, with no evidence of transplacental fetal infection. Thrombophilia and prenatally detected IUGR emerged as independent predisposing factors for the potentially lethal SARS-COV-2 placentitis. This article is protected by copyright. All rights reserved. [ABSTRACT FROM AUTHOR]

Research interest on abdominal aorta branches and abdominal viscera morphometry is renewed by technological evolution and development of new radiologic and clinical applications including stent grafts and chemoembolisation materials. Despite that, data on morphometry of abdominal aorta branches and abdominal viscera are lacking. To investigate this subject authors performed a morphometric study on 50 adult fresh and embalmed Caucasian cadavers and examined abdominal aorta branches', kidney and spleen morphometry. Our results on arteries' morphometry did not differ significantly from those of the literature; yet, we discovered significant differences between fresh and embalmed cadavers on viscera morphometry, spleen and kidneys. We also found previously unreported correlations between abdominal aorta branches' morphometric characteristics. Even more, we identified correlations between regional arteries and viscera morphometric characteristics, proposing a new factor determining viscera development. Finally, we performed an extensive literature review so to place our results in an anatomic, embryologic and, even more, a clinical context. We believe that our results add knowledge on abdominal aorta branches and viscera morphometry and are valuable for clinical, radiological and surgical applications including visceral arteries' aneurysms investigation and treatment, chemoembolisation procedures, stent grafts design and transplantation. [ABSTRACT FROM AUTHOR]

Aging is the single biggest risk factor for malignant transformation. Among the most common age-associated malignancies are non-melanoma skin cancers, comprising the most common types of human cancer. Here we show that mutant H-Ras activation in mouse epidermis, a frequent event in cutaneous squamous cell carcinoma (SCC), elicits a differential outcome in aged versus young mice. Whereas H-Ras activation in the young skin results in hyperplasia that is mainly accompanied by rapid hair growth, H-Ras activation in the aged skin results in more dysplasia and gradual progression to in situ SCC. Progression is associated with increased inflammation, pronounced accumulation of immune cells including T cells, macrophages and mast cells as well as excessive cell senescence. We found not only an age-dependent increase in expression of several pro-inflammatory mediators, but also activation of a strong anti-inflammatory response involving enhanced IL4/IL10 expression and immune skewing toward a Th2 response. In addition, we observed an age-dependent increase in the expression of Pdl1, encoding an immune suppressive ligand that promotes cancer immune evasion. Moreover, upon switching off oncogenic H-Ras activity, young but not aged skin regenerates successfully, suggesting a failure of the aged epidermal stem cells to repair damaged tissue. Our findings support an age-dependent link between accumulation of senescent cells, immune infiltration and cancer progression, which may contribute to the increased cancer risk associated with old age. [ABSTRACT FROM AUTHOR]

Oncogene-induced reactive oxygen species (ROS) have been proposed to be signaling molecules that mediate proliferative cues. However, ROS may also cause DNA damage and proliferative arrest. How these apparently opposite roles can be reconciled, especially in the context of oncogene-induced cellular senescence, which is associated both with aberrant mitogenic signaling and DNA damage response (DDR)-mediated arrest, is unclear. Here, we show that ROS are indeed mitogenic signaling molecules that fuel oncogene-driven aberrant cell proliferation. However, by their very same ability to mediate cell hyperproliferation, ROS eventually cause DDR activation. We also show that oncogenic Ras-induced ROS are produced in a Rac1 and NADPH oxidase (Nox4)-dependent manner. In addition, we show that Ras-induced ROS can be detected and modulated in a living transparent animal: the zebrafish. Finally, in cancer we show that Nox4 is increased in both human tumors and a mouse model of pancreatic cancer and specific Nox4 small-molecule inhibitors act synergistically with existing chemotherapic agents. [ABSTRACT FROM AUTHOR]

Common fragile sites (CFSs) are regions of the genome prone to breakage by replication inhibitors (extrinsic replication stress). Recently, we and others observed that oncogene-induced replication stress (RS) induces DNA damage from the earliest stages of cancer. Our aim was to perform a genome-wide analysis in precancerous and cancerous experimental models to examine whether allelic imbalance occurs within CFSs. Subsequently, CFSs sequence characteristics were assessed. We used a growth-factor-induced human skin hyperplasia and a H-ras-induced mouse hyperplastic urothelium as preneoplastic models, along with an inducible U2OS-CDT1Tet-ON cancer cell line model, all bearing established oncogene-induced RS stimuli. Human DNA was analysed with Affymetrix SNP microarrays, while mouse DNA was analysed with Nimblegen array CGH. We studied 56 aphidicolin-type CFSs and 1914 regions of control, nonfragile DNA. Our theoretical in silico analysis spanned 2.16 billion nonoverlapping bases on human chromosomes 1–22. Our results provide direct experimental evidence indicating that genomic alterations were more common within CFSs in epidermal and urothelial preneoplastic lesions as well as in cancer. CFSs were on average less flexible than nonfragile regions, contained more guanine–cytosine (GC) and Alu sequences. Importantly, regions with loss-of-heterozygosity were also less flexible and had a higher Alu percentage.Oncogene (2008) 27, 3256–3264; doi:10.1038/sj.onc.1210989; published online 17 December 2007 [ABSTRACT FROM AUTHOR]

Background: E2F-1 expression is positively associated with tumour growth in oesophageal squamous-cell carcinomas (OSCC), while it exhibits oncosuppressive features in colonic adenocarcinomas (AC). To date there are no data regarding E2F-1 expression and its relationship with tumour kinetics (proliferation, apoptosis) in adenocarcinomas that develop on Barrett oesophagus. Aim: As oesophageal adenocarcinomas occur almost exclusively in the metaplastic Barrett epithelium and the opposing E2F-1 behaviour seems to be cell and tissue-type dependent, we examined the manner in which E2F-1 acts in AOs of Barrett oesophagus. Methods: We estimated the immunohistochemical expression of E2F-1, Ki-67, caspase-3 and p53 immunohistochemical status in 35 Barrett oesophagus ACs. Results: E2F-1 immunopositivity correlated inversely with Ki-67, by semi-serial section and statistical analysis (p = 0.023, Spearman correlation). Semi-serial section analysis revealed a direct association between E2F-1 and caspase-3 staining. No correlation was found with p53 status. Cases with higher E2F-1 immunoexpression exhibited longer survival (p = 0.047, Cox-regression). Conclusions: E2F-1 expression was negatively related to tumour proliferation in ACs of Barrett oesophagus. Additionally, E2F-1 immunohistochemical status correlated positively with patient survival. These findings are opposite from those seen in OSCCs, suggesting that the tumour-suppressing E2F-1 behaviour in oesophageal adenocarcinomas is possibly due to the intestinal-type nature of the metaplastic Barrett mucosa. [ABSTRACT FROM AUTHOR]

Aims Reports concerning the expression of cytoplasmic components of the mitogen-activating protein kinase (MAPK) pathway in lung cancer are limited. One of the molecules participating in this pathway is the product of the c-mos proto-oncogene. In vitro investigations, in somatic cells, have shown that c-mos expression has opposing effects on cell cycle progression suggesting that it may represent an important determinant of aberrant cell function. In this study we analysed, by immunohistochemical means, its status in a series of lung carcinomas and correlated the findings with clinicopathological parameters and survival of the patients. Methods and results Sixty cases of lung carcinomas were included in the study. These comprised 52 non-small (NSCLCs) and eight small cell lung carcinomas (SCLCs). Sections from the carcinomas were immunostained with the polyclonal anti-c-mos antibody P-19. Specificity was tested by using the appropriate control peptide and control cell lines. Expression was observed in 63% of the cases, with NSCLCs showing higher reactivity (67%) than SCLCs (37.5%). Staining was observed mainly to the cytoplasm and membranes of the cancerous cells, but some nuclei reacted as well. An intratumour heterogeneous immunoreactivity was noticed. The most interesting and unexpected finding was that c-mos positive staining was associated with better recurrence-free survival in our series, regardless of histological type (P = 0.035). Furthermore, favourable disease-related and recurrence-free survival was observed in the SqC group with c-mos immunoreactivity (P < 0.001). Conclusions c-mos proto-oncogene is expressed in a significant proportion of lung carcinomas and may play a role in its development. The fact that its expression is associated with a relatively good prognosis may be indicative of a negative impact on tumour growth. [ABSTRACT FROM AUTHOR]

This study investigated the combined immunoexpression of p53, p21, bcl-2, bax, Rb and Ki67 proteins in colorectal adenocarcinomas and correlated expression patterns with tumour stage and grade. Paraffin sections from 98 cases of colorectal adenocarcinomas were stained by immunohistochemistry for p53, p21, bcl-2, bax, Rb and MIB-1 (Ki67) proteins. In addition, 12 cases of colorectal adenomas and normal colorectal mucosa were studied in parallel. P53, p21, bcl-2, bax, Rb and Ki67 proteins were detected in at least 5% of tumour cells in 63/98, 72/98, 52/98, 96/98 and 98/98 adenocarcinomas, respectively. Comparative study of the normal-adenoma-carcinoma tissues revealed abrogation of the normal immunotopography in adenomas and adenocarcinomas, and considerable modifications, increase or reduction, of the expression of p53, p21, bcl-2, bax, Rb and Ki67 proteins in adenocarcinomas when compared with normal mucosa and adenomas. Statistically significant correlations were found between low bax expression and Dukes C stage of carcinomas, Ki67 expression and carcinoma grade, and Ki67 and Rb expression. P53, p21, bcl-2 and Rb immunoexpression did not correlate with tumour stage or grade. Our findings show that low bax immunoexpression is frequently related to colorectal adenocarcinomas with lymph node metastases suggesting that low levels of bax expression play a role in late stage colorectal cancer. The correlation between Ki67 and Rb expression, in view of previous data that the hyperphosphorylated inactive Rb protein is frequently increased in colorectal adenocarcinomas, suggests that Rb protein is somewhat ineffective in inhibiting the cell-cycle progression in these malignancies. Furthermore, our findings provide immunohistochemical evidence that the abrogation of the normal immunotopography and the modifications of the expression of p53, p21, bcl-2, bax, Rb and Ki67 proteins reflect important events in colorectal oncogenesis. [ABSTRACT FROM AUTHOR]

This study was undertaken in order to investigate the molecular nature of the p53 gene in 19 laryngeal squamous cell carcinomas and dysplasias. Moreover, we have examined the possible relationship between proliferating cell nuclear antigen (PCNA) expression and p53 protein detection status in 42 laryngeal premalignant and malignant lesions in which 14 of the 19 samples used in the molecular study were included. p53 gene analysis was performed with the single-strand conformation polymorphism technique. PCNA was stained with the peroxidase/antiperoxidase immunohistochemical method using the monoclonal antibody PC-10. Data from previous work concerning p53 expression was used. We found that 9 of 12 of the immunohistochemically p53 positive (+) cases had mutations in exons 5 or 6. In the remaining immunohistochemically p53(+) and p53 negative (-) specimens there was no indication of sequence alterations. Furthermore, we did not observe any deletions in the chromosomal region 17p31.1 which encodes exons 4-8 of the p53 gene. The PCNA labelling index (LI) increased progressively with p53 protein detection status (percentage of cells immunohistochemically positive for p53). The difference between the group with the higher percentage of p53(+) cells and the others was statistically significant. These data show that although there is a discrepancy between immunohistochemical demonstration of p53 and molecular analysis, a large proportion of the former harbours the mutant form of the protein. In addition, p53 overexpression is positively correlated with PCNA LI, a finding which accompanies tumour progression. [ABSTRACT FROM AUTHOR]

In order to evaluate the expression of p53 protein in 28 premalignant and 40 malignant squamous cell proliferations of the larynx and its relationship to tobacco consumption, human papillomavirus infection and differentiation grade of the lesions, p53 expression was examined by means of a microwave post-fixation immunohistochemical method using the PAb 240 and PAb 1801 monoclonal antibodies. HPV infection was assessed by non-isotopic in situ hybridization (NISH) and polymerase chain reaction (PCR). A large proportion of carcinomas (77.5%) and dysplasias (61%) expressed p53. No difference was found between differentiation grades of the lesions regarding p53 detection (P > 0.1), but moderate or intense p53 expression was more frequent in the carcinomas (P < 0.05). A statistical correlation was found between cigarette consumption and both p53 detection and p53 staining intensity (P < 0.05 in each case). HPV study revealed HPV 16 and 18 infection only in carcinomas. The frequency was 28% and the physical state of the virus as demonstrated by NISH was integration into the genome. We observed an inverse relationship between HPV infection and p53 expression (P = 0.006). Our findings suggest that p53 overexpression is a common and early event which increases in frequency with progression of laryngeal squamous cell carcinoma. The expression of p53 is influenced by tobacco and high-risk types of HPV. [ABSTRACT FROM AUTHOR]

Epidermal growth factor (EGF) and its receptor (EGFr) constitute an important and well-characterized mitogenic system in various ectodermal tissues. We evaluated the expression of EGFr and examined possible EGFr gene alterations in 18 formalin-fixed, paraffin-embedded squamous cell lung carcinomas (SCLC) by an immunohistochemical assay, Southern blotting and differential polymerase chain reaction (DPCR). The immunohistochemical study employing the F and EGF-R1 monoclonal antibodies, directed against the intra- and extra-cellular portion of the receptor respectively, showed EGFr over-expression in 89% of the SCLC cases examined. All cases showed positive immunostaining for both antibodies, thus excluding the possibility of truncated receptors. In addition, analysis of the EGFr gene was carried out by Southern blotting and DPCR on paraffin extracted DNA from the same carcinoma cases. We found amplification of the EGFr gene in 5/18 (27%) SCLCs. All 5 positive cases showed EGFr over-expression, suggesting a possible correlation between the presence of EGFr gene amplification and over-expression of receptor protein. No correlation was observed among EGFr staining, EGFr gene amplification and differentiation of carcinomas. In addition, Southern blot analysis with HER-A2, a probe which hybridizes a sequence of the receptor's intracellular domain, revealed three novel EcoRI restriction fragment patterns. We suggest that these patterns correspond to EcoRI polymorphic sites of the receptor's tyrosine kinase domain. [ABSTRACT FROM AUTHOR]

Presents an experiment which focused on the absence of p53 gene mutations in skin fibroblasts derived from patients with systemic sclerosis (SSc). Effect of skin fibroblasts on the visceral fibrosis of patients with SSc; Factors associated with the mis-sense mutations of the p53 transcription factor gene.

A letter to the editor is presented in response to the article about the contribution of the p53-inducible gene 3 (PIG3) that appeared online in the July 5, 2010 issue.

The serum levels of two tumor markers in patients with diagnosed primary squamous cell lung carcinoma were measured and their possible correlation with lymph node involvement was investigated. Seventy-seven patients with squamous cell lung carcinoma and mean age of 62.1 years were included in the study. Blood was collected from all patients, and a tumor specimen was submitted for histological examination. All patients underwent radical resection of the primary tumor with mediastinal lymph node dissection. The stage of disease was assessed intraoperatively. Serum levels of CEA and SCC-Ag were measured with an immunoenzymic method. The t-test and the X2 test with Yates correction were used for the statistical analysis of data.