The role of fetal programming in human carcinogenesis - May the Barker hypothesis explain interindividual variability in susceptibility to cancer insurgence and progression?

The growing incidence of cancers is pushing oncologists to find out new explanations other than the somatic mutation theory, based on the accumulation of DNA mutations. In particular, the embryo-fetal exposure to an increasing number of environmental factors during gestation might represent a trigger able to influence the susceptibility of the newborn to develop cancer later in life. This idea agrees with the fetal programming theory, also known as the Barker hypothesis. Here the role of insulin-like growth factors, thymosin beta-4, and epigenome are discussed as mediators of cancer in prenatal human development. The role of epigenetic factors that during gestation increase the predisposition to develop cancer and the similarities in the gene expression (like MMP9, OPN, TP53 and CDKN2A) between embryonic development and cancer are key factors. Likewise, maternal obesity might be able to re-program embryo-fetal development with long-term changes, including an increased risk to develop neuroblastoma and acute leukemia. Birth weight alone and birth weight corrected for gestational age are proposed as important variables capable of predicting the vulnerability to develop cancers. According to the findings here reported, we hypothesize that cancer prevention should start during gestation by improving the quality of maternal diet. In conclusion, the Barker hypothesis should be applied to cancer as well. Therefore, the identification of the epigenetic factors of cancer appears mandatory, so that the cancer prevention might start in the womb before birth.

Ultrastructural findings of lung injury due to Vaccine-induced Immune Thrombotic Thrombo- cytopenia (VITT) following COVID-19 vaccination: a scanning electron microscopic study.

Vaccine-induced immune thrombotic thrombocytopenia (VITT) is a rare new syndrome occurring after the ChAdOx1 nCoV-19 vaccine immunization. Patients with VITT are characterized by a variable clinical presentation, likewise also the outcome of these patients is very variable. Here we report the lung ultrastructural findings in the course of VITT of a 58-year-old male patient. Alveoli were mainly dilated, irregular in shape, and occupied by a reticular network of fibrin, while interalveolar septa appeared thickened. The proliferation of small capillaries gave rise to plexiform structures and pulmonary capillary hemangiomatosis-like features. Near the alveoli occupied by a dense fibrin network, the medium-sized arteries showed a modified wall and an intraluminal thrombus. This scenario looks quite similar to that found during COVID-19, where the lungs suffer from the attack of the antigen-antibodies complexes and the virus respectively. In both diseases, the final outcome is a severe inflammation, activation of the haemostatic system and fibrinolysis.

Thrombotic sinusoiditis and local diffuse intrasinusoidal coagulation in the liver of subjects affected by COVID-19: the evidence from histology and scanning electron microscopy.

OBJECTIVE: Liver injury has been reported in patients with COVID-19. This condition is characterized by severe outcome and could be related with the ability of SARS-CoV-2 to activate cytotoxic T cells. The purpose of this study is to show the histological and scanning electron microscopy features of liver involvement in COVID-19 to characterize the liver changes caused by the activation of multiple molecular pathways following this infection. PATIENTS AND METHODS: Liver biopsies from 4 patients (3 post-mortems and 1 in vivo) with COVID-19 were analyzed with histology and by scanning electron microscopy. RESULTS: The liver changes showed significant heterogeneity. The first case showed ground glass hepatocytes and scattered fibrin aggregates in the sinusoidal lumen. The second evidenced intra-sinusoidal thrombi. The third was characterized by sinusoidal dilatation, atrophy of hepatocytes, Disse's spaces dilatation and intra-sinusoidal aggregates of fibrin and red blood cells. The fourth case exhibited diffuse fibrin aggregates in the dilated Disse spaces and microthrombi in the sinusoidal lumen. CONCLUSIONS: In COVID-19-related liver injury, a large spectrum of pathological changes was observed. The most peculiar features were very mild inflammation, intra-sinusoidal changes, including sinusoidal dilatation, thrombotic sinusoiditis and diffuse intra-sinusoidal fibrin deposition. These findings suggested that a thrombotic sinusoiditis followed by a local diffuse intra-vascular (intra-sinusoidal) coagulation could be the typical features of the SARS-CoV-2-related liver injury.

Fetal programming of COVID-19: may the barker hypothesis explain the susceptibility of a subset of young adults to develop severe disease?

The risk stratification of young adults between subjects who will develop a mild form COVID-19 and subjects who will undergo a severe disease remains inaccurate. In this review, we propose that the Barker hypothesis might explain the increased susceptibility to severe forms of COVID-19 in subjects who underwent intrauterine growth restriction (IUGR). In this paper evidence indicating an association between a low birth weight and an adult phenotype which might favor a severe outcome of SARS-CoV-2 infection are presented: lower lung functional capacity; increased respiratory morbidity; changes in fibrinogen and Factor VII serum levels and dysregulation of the hemostasis and thrombosis system; acquisition of a pro-thrombotic phenotype; low nephron number, with decreased ability to sustain renal function and increased renal morbidity; heart remodeling, with a less efficient cardiac function; endothelial dysfunction, a risk factor for the insurgence of the multiple organ failure; remodeling of arteries, with changes in the elastic properties of the arterial wall, predisposing to the insurgence and progression of atherosclerosis; dysfunction of the innate immune system, a risk factor for immune diseases in adulthood. These data suggest that young and adult subjects born too small (IUGR) or too early (pre-terms) might represent a subgroup of "at risk subjects", more susceptible toward severe forms of COVID-19. Given that LBW may be considered a surrogate of IUGR, this phenotypic marker should be included among the indispensable clinical data collected in every patient presenting with SARS-COV-2 infection, irrespectively of his/her age.

Vaccine-induced severe thrombotic thrombocytopenia following COVID-19 vaccination: a report of an autoptic case and review of the literature.

OBJECTIVE: Vaccine-induced immune thrombocytopenia (VITT) is a new syndrome occurring primarily in healthy young adults, with a female predominance, after receiving the first dose of ChAdOx1 nCoV-19 vaccine. We describe VITT syndrome characterized by severe thrombosis and thrombocytopenia found in our patient, with fatal outcome. CASE REPORT: A 58-year-old man, after 13 days from the first administration of ChAdOx1 nCoV-19 vaccine (AstraZeneca), presented with abdominal pain, diarrhea and vomitus. Laboratory tests revealed a severe thrombocytopenia, low fibrinogen serum levels and marked increase of D-dimer serum levels. The patient quickly developed a multiple organ failure, till death, three days after the hospital admission. RESULTS: At histology, in the lungs, interalveolar septa appeared thickened with microthrombi in the capillaries and veins. Interalveolar septa appeared thickened and showed vascular proliferation. Thrombi were detected in the capillaries of glomerular tufts. In the hearth, thrombi were observed in veins and capillaries. In the liver, voluminous fibrin thrombi were diffusely observed in the branches of the portal vein. Microthrombi were also found in the vasa vasorum of the wall of abdominal aorta. In the brain, microthrombi were observed in the capillaries of the choroid plexuses. Diffuse hemorrhagic necrosis was observed in the intestinal wall with marked congestion of the venous vessels. CONCLUSIONS: In our patient, the majority of data necessary for a VITT final diagnosis were present: thrombocytopenia and thrombosis in pulmonary, portal, hepatic, renal and mesenteric veins, associated with a marked increase of D-dimer serum levels. The finding of cerebral thrombosis in choroid plexuses, is a new finding in VITT. These features are suggestive for a very aggressive form of VITT.

Immunohistochemical findings in the lungs of COVID-19 subjects: evidence of surfactant dysregulation.

OBJECTIVE: Acute respiratory distress syndrome (ARDS) is characterized by quantitative and qualitative changes in surfactant composition, leading to surfactant dysregulation with alveolar collapse and acute respiratory hypoxic failure. Recently, surfactant has been hypothesized to play a relevant role in COVID-19, representing a strong defender against SARS-CoV-2 infection. The aim of our work was the study of immunohistochemical surfactant expression in the lungs of patients died following SARS-CoV-2 ARDS, in order to shed light on a possible therapeutic surfactant administration. PATIENTS AND METHODS: We investigated four patients who died due to ARDS following SARS-COV-2 infection and four patients submitted to lung biopsy, in the absence of SARS-CoV-2 infection. In all 8 cases, lung specimens were immunostained with anti-surfactant protein A (SP-A) and B (SP-B). RESULTS: In control subjects, reactivity for SP-B was restricted to type II alveolar cells. Immunostaining for SP-A was observed on the surface of alveolar spaces. In the COVID-19 positive lungs, immunoreactivity for SP-B was similar to that observed in control lungs; SP-A was strongly expressed along the alveolar wall. Moreover, dense aggregates of SP-A positive material were observed in the alveolar spaces. CONCLUSIONS: Our immunohistochemical data show the dysregulation of surfactant production in COVID-19 patients, particularly regarding SP-A expression. The increased presence of SP-A in condensed masses inside alveolar spaces could invalidate the therapeutic efficacy of the treatment with exogenous surfactant.

Trace elements and the carotid plaque: the GOOD (Mg, Zn, Se), the UGLY (Fe, Cu), and the BAD (P, Ca)?

Multiple epidemiological studies have suggested that industrialization and progressive urbanization should be considered one of the main factors responsible for the rising of atherosclerosis in the developing world. In this scenario, the role of trace metals in the insurgence and progression of atherosclerosis has not been clarified yet. In this paper, the specific role of selected trace elements (magnesium, zinc, selenium, iron, copper, phosphorus, and calcium) is described by focusing on the atherosclerotic prevention and pathogenesis plaque. For each element, the following data are reported: daily intake, serum levels, intra/extracellular distribution, major roles in physiology, main effects of high and low levels, specific roles in atherosclerosis, possible interactions with other trace elements, and possible influences on plaque development. For each trace element, the correlations between its levels and clinical severity and outcome of COVID-19 are discussed. Moreover, the role of matrix metalloproteinases, a family of zinc-dependent endopeptidases, as a new medical therapeutical approach to atherosclerosis is discussed. Data suggest that trace element status may influence both atherosclerosis insurgence and plaque evolution toward a stable or an unstable status. However, significant variability in the action of these traces is evident: some - including magnesium, zinc, and selenium - may have a protective role, whereas others, including iron and copper, probably have a multi-faceted and more complex role in the pathogenesis of the atherosclerotic plaque. Finally, calcium and phosphorus are implicated in the calcification of atherosclerotic plaques and in the progression of the plaque toward rupture and severe clinical complications. In particular, the role of calcium is debated. Focusing on the COVID-19 pandemia, optimized magnesium and zinc levels are indicated as important protective tools against a severe clinical course of the disease, often related to the ability of SARS-CoV-2 to cause a systemic inflammatory response, able to transform a stable plaque into an unstable one, with severe clinical complications.

Pseudoangiomatous stromal hyperplasia (PASH) presenting as axillary lump: case report and review of the literature.

Pseudoangiomatous stromal hyperplasia (PASH) is an uncommon benign mesenchymal breast lesion. There are extremely rare reports of PASH arising in accessory breast tissue. To date, in literature, fewer than 10 cases of PASH occurring in axillary region have been described. We report a case presenting as axillary lump in a young woman. A 20-year-old female presented to our surgical unit for a progressively growing and painful palpable mass of the right axilla for about a year. Before surgery an ultrasound was performed. The patient underwent local excision of the lesion under local anaesthesia. Through histological and immunohistochemical examination a pseudoangiomatous stromal hyperplasia (PASH) was diagnosed. At 6 months of followup the patient is free of disease. It is important to include PASH also in the differential diagnosis of axillary lumps. Histological examination of the surgical specimen and surgery represent, respectively, the mainstay for diagnosis and therapy.

Low vascularization of the nephrogenic zone of the fetal kidney suggests a major role for hypoxia in human nephrogenesis.

CD31 reactivity is generally utilized as a marker of endothelial cells. CD31 immunoreactivity in the developing human kidney revealed that fetal glomerular capillary endothelial cells change their immunohistochemical phenotype during maturation. The aim of this study was to analyze CD31 reactivity in the fetal human kidney in the different stages of intrauterine development: We observed different distribution of CD31-reactive vascular progenitors in the different areas of the developing kidney. In particular, the nephrogenic zone and the renal capsule were characterized by a scarcity of CD31-reactive cells at all gestational ages. These data suggest the hypothesis that nephrogenesis does not need high oxygen levels and confirms a major role of hypoxia in nephrogenesis.

Stem/progenitor cells in the developing human cerebellum: an immunohistochemical study.

The aim of this study was to analyze, by immunohistochemistry, the occurrence of stem/progenitor cells localized in the different niches of the developing human cerebellum. To this end, cerebellar samples were obtained from 3 fetuses and 3 newborns ranging, respectively, from 11 to 24 and from 30 to 38 weeks of gestation. Specimens were 10% formalin-fixed, routinely processed and paraffin-embedded; 3 µm-tick sections were immunostained with anti-SOX2 and PAX6 antibodies. Our study evidenced SOX2 and PAX6 immunoreactivity in precursors cells in all six developing human cerebella. SOX2 was expressed in precursors of different neural cell types, including Purkinje neurons, stellate cells, basket cells and Golgi cells. In the cerebellar cortex, SOX2 expression changed during gestation, being highly expressed from the 20th up to the 24th week, whereas at the 30th and at the 34th week SOX2 immunoreactivity was restricted to the Purkinje cell layer and the inner zone. Cerebellar human cortex was negative at the 38th week of gestation. PAX6 immunoreactivity was restricted to granule cell precursors in the external granule layer (EGL), being detected at all gestational ages. Our study indicates SOX2 and PAX6 as two useful markers of stem/progenitor cells that highlight the different germinative zones in the developing human cerebellum.

Immunohistochemical markers of neural progenitor cells in the early embryonic human cerebral cortex.

The development of the human central nervous system represents a delicate moment of embryogenesis. The purpose of this study was to analyze the expression of multiple immunohistochemical markers in the stem/progenitor cells in the human cerebral cortex during the early phases of development.  To this end, samples from cerebral cortex were obtained from 4 human embryos of 11 weeks of gestation. Each sample was formalin-fixed, paraffin embedded and immunostained with several markers including GFAP, WT1, Nestin, Vimentin, CD117, S100B, Sox2, PAX2, PAX5, Tß4, Neurofilament, CD44, CD133, Synaptophysin and Cyclin D1. Our study shows the ability of the different immunohistochemical markers to evidence different zones of the developing human cerebral cortex, allowing the identification of the multiple stages of differentiation of neuronal and glial precursors. Three important markers of radial glial cells are evidenced in this early gestational age: Vimentin, Nestin and WT1. Sox2 was expressed by the stem/progenitor cells of the ventricular zone, whereas the postmitotic neurons of the cortical plate were immunostained by PAX2 and NSE. Future studies are needed to test other important stem/progenitor cells markers and to better analyze differences in the immunohistochemical expression of these markers during gestation.

Fetal programming of the human brain: is there a link with insurgence of neurodegenerative disorders in adulthood?

In recent years, evidence is growing on the role played by gestational factors in shaping brain development and on the influence of intrauterine experiences on later development of neurodegenerative diseases including Parkinson's (PD) and Alzheimer's disease (AD). The nine months of intrauterine development and the first three years of postnatal life are appearing to be extremely critical for making connections among neurons and among neuronal and glial cells that will shape a lifetime of experience. Here, the multiple epigenetic factors acting during gestation - including maternal diet, malnutrition, stress, hypertension, maternal diabetes, fetal hypoxia, prematurity, low birth weight, prenatal infection, intrauterine growth restriction, drugs administered to the mother or to the baby - are reported, and their ability to modulate brain development, resulting in interindividual variability in the total neuronal and glial burden at birth is discussed. Data from recent literature suggest that prevention of neurodegeneration should be identified as the one method to halt the diffusion of neurodegenerative diseases. The "two hits" hypothesis, first introduced for PD and successfully applied to AD and other neurodegenerative human pathologies, should focus our attention on a peculiar period of our life: the intrauterine and perinatal periods. The first hit to our nervous system occurs early in life, determining a PD or AD imprinting to our brain that will condition our resistance or, alternatively, our susceptibility to develop a neurodegenerative disease later in life. In conclusion, how early life events contribute to late-life development of adult neurodegenerative diseases, including PD and AD, is emerging as a new fascinating research focus. This assumption implies that research on prevention of neurodegenerative diseases should center on events taking place early in life, during gestation and in the perinatal periods, thus presenting a new challenge to perinatologists: the prevention of neurodegenerative human diseases.

Zinc content and distribution in the newborn liver.

The newborn liver is a proven model for the study of liver storage of copper and iron. We analyzed zinc concentration and distribution in the livers of newborns and infants using a systematic tissue-sampling technique. We studied 14 newborns of 26-41 weeks of gestation (WG). One stillborn, and three infants (52-90 days old). At autopsy, a longitudinal liver slice extending from the right to the left lobe was subdivided into 10 samples that were analyzed for zinc concentration by atomic absorption spectroscopy. The mean zinc concentration in the newborn liver was 639 micrograms/g of dry tissue (dt). A striking interindividual variability in zinc liver stores was observed; the hepatic concentration of the metal ranged from 300 to 1,400 micrograms/g dt. We found a correlation between zinc liver content and gestational age. In newborns of 27-32 WG, the hepatic zinc concentration was significantly higher (p < 0.01) than in newborns of 34-41 WG. Zinc stores decreased in the postnatal period; in the infant group, the mean liver zinc concentration was 148 micrograms/g dt. The analysis of zinc concentration in 10 blocks from each liver revealed a regular distribution of the metal, without significant differences between liver lobes. Our data show that the newborn liver can be considered an interesting model for the study of zinc storage, which appears to correlate inversely with gestational age. From a practical point of view, the observed regular distribution of zinc implies that, at least in this model, zinc content determined in a small liver sample is representative of zinc content in the whole liver.

Chromosome changes in nonneoplastic tissue. Numerical and structural abnormalities in nasal polyps with atypical stromal cells.

Cytogenetic investigation on short-term cultures of 13 nasal polyps disclosed the presence of chromosome aberrations in three cases: one (a recurrence) showed numerical changes; the other two had structural abnormalities, an inv(12)(q15q22) in one case, a der(6)t(6;12)(q22;q15) in the other. The three cases were characterized histologically by the presence of frequent atypical stromal cells, and were positive for vimentin and smooth muscle actin. Of the remaining 10 cases, three were not analyzable, and seven had normal karyotypes, although random structural changes were seen in two of them.