Large Nests Research Articles

Usefulness of Dermatoscopy for the Preoperative Assessment of the Histopathologic Aggressiveness of Basal Cell Carcinoma.

BackgroundLimited information is available regarding dermatoscopic differences between non-aggressive and aggressive types of basal cell carcinoma (BCC).ObjectiveTo investigate dermatoscopic differences between non-aggressive and aggressive types.MethodsWe evaluated 145 histopathologically confirmed BCCs from 141 patients. Histopathologic types and aggressiveness from 4 mm punch biopsy and their dermatoscopic findings were evaluated. We assessed the statistical significance of dermatoscopic differences between non-aggressive and aggressive types. To objectively predict aggressiveness, we created a "dermatoscopic index of BCC aggressiveness" in which 1 point was added and subtracted for each dermatoscopic finding significantly higher in aggressive and non-aggressive types, respectively.ResultsLarge blue-gray ovoid nests were found more frequently in non-aggressive type than aggressive one (85/105 [80.9%] vs. 21/40 [52.5%], p=0.001). Compared to non-aggressive type, aggressive type had more multiple blue-gray globules (29/40 [72.5%] vs. 57/105 [54.3%], p=0.046), arborizing telangiectasia (29/40 [72.5%] vs. 48/105 [45.7%], p=0.004), and concentric structure (11/40 [27.5%] vs. 12/105 [11.4%], p=0.018). Regarding dermatoscopic index, cases of aggressive type with a score of 1 were most common (n=18, 45.0%), followed by a score of 2 (n=14, 35.0%). Limited number of aggressive type of BCCs and the effect of width on the determination of histopathologic aggressiveness.ConclusionAggressive type BCCs more often exhibited multiple blue-gray globules, arborizing telangiectasia, and concentric structure, while the non-aggressive type exhibited large blue-gray ovoid nests more frequently. Score exceeding 2 on the dermoscopic index can be screening criteria for aggressiveness. These dermatoscopic features and dermoscopic index could be useful for assessing aggressiveness of BCCs before surgery.

Paraganglioma-like dermal melanocytic tumor.

Paraganglioma-like dermal melanocytic tumor (PDMT) is a rare subtype of benign dermal melanocytic tumor, first described in 2004. Its histopathologic features resemble those of paraganglioma, showing presence of a distinctive partitioning of the tumor into small and large packets, nests, or short cords by delicate fibrous septa (zellballen pattern). But the immunostaining characteristics are those of melanocytic lesions, as PDMT express S-100, melan A, HMB 45 and lack pancytokeratin markers. It has a benign course, although a lesion of low malignant potential cannot be excluded. We describe a case of 60-year-old female who presented with three PDMT lesions on her right leg. To the best of our knowledge this is the first case reported from India.

Case Report: Large nested variant urothelial carcinoma –invasive malignancy masquerading as low grade disease

Introduction The large nested variant of urothelial carcinoma (LNVUC) is a newly described and rare subtype of urothelial carcinoma. It is characterised by bland cytological features and a large nested architecture similar in appearance to low grade urothelial carcinoma with an inverted growth pattern. To date only 23 cases in a single series have been described. Case Report We describe the case of a 59 year old male with LNVUC whose tumour was initially misdiagnosed as a non-invasive low grade urothelial carcinoma. At a subsequent re-resection, his tumour was correctly re-classified as LNVUC with extensive invasion of the muscularis propria. Radical cystectomy and formation of an ileal conduit was performed. His operative specimen revealed invasion of prostatic stroma and perivesical fat, with all surgical margins clear. He is currently free from clinical recurrence 12 months after his cystectomy. Conclusion LNVUC is a newly described and rare urothelial carcinoma subtype. It characteristically possesses bland cytological features and may mimic low grade urothelial cancer. Despite its bland appearance it behaves aggressively with invasion, metastasis and death being common.

Y-linked Mendelian inheritance of giant and dwarf male morphs in shell-brooding cichlids

Behavioural variation among conspecifics is typically contingent on individual state or environmental conditions. Sex-specific genetic polymorphisms are enigmatic because they lack conditionality, and genes causing adaptive trait variation in one sex may reduce Darwinian fitness in the other. One way to avoid such genetic antagonism is to control sex-specific traits by inheritance via sex chromosomes. Here, controlled laboratory crossings suggest that in snail-brooding cichlid fish a single locus, two-allele polymorphism located on a sex-linked chromosome of heterogametic males generates an extreme reproductive dimorphism. Both natural and sexual selection are responsible for exceptionally large body size of bourgeois males, creating a niche for a miniature male phenotype to evolve. This extreme intrasexual dimorphism results from selection on opposite size thresholds caused by a single ecological factor, empty snail shells used as breeding substrate. Paternity analyses reveal that in the field parasitic dwarf males sire the majority of offspring in direct sperm competition with large nest owners exceeding their size more than 40 times. Apparently, use of empty snail shells as breeding substrate and single locus sex-linked inheritance of growth are the major ecological and genetic mechanisms responsible for the extreme intrasexual diversity observed in Lamprologus callipterus.

The Rufous Hornero (Furnarius rufus) nest as an incubation chamber

Foraging and incubation are mutually exclusive activities for parent birds. A trade-off is generated when a combination of food availability and temperature regulation force birds to choose one and neglect the other, at least temporarily. The Rufous Hornero builds large, oven-like, mud nests, the evolutionary cause of which remains unknown. We tested that temperature variation inside the nest is that which is expected if one function of the nest were for temperate regulation. If so, this would suggest that the nest works as an incubation chamber (but which now may serve more than one function). We divided nests into two natural treatments: nests that received more continuous direct sunshine (sun), and those that received less direct sunshine, due to shade from trees or buildings (shade). Thermometer data loggers were placed in the nest cavity and outside, in the shade of the nest, and temperature was measured every 10min. We predicted that temperatures would consistently be higher and less variable in nests than outside nests. Also, at higher ambient temperatures the nest would function better as an incubation chamber as a consequence of having evolved in a hotter climate. Thus, in Curitiba, where temperatures are lower than where the species (and nest) evolved, nests in greater sunshine should have thermal characteristics that support the incubation chamber hypothesis. Predictions were supported: with Repeated Measures ANOVA and t-tests, we found that temperatures were more constant and higher in nests, especially when in the sun, and as the season progressed (hotter ambient temperatures). We conclude that the large mud nest of the Rufous Hornero works as an incubation chamber that likely evolved to help resolve the incubation-foraging trade-off in the very seasonal and hot regions where the bird evolved. Thus, as an incubation chamber, the nest allows the bird to forage rather than incubate thereby resolving the foraging-incubation trade-off and potentially favoring survival of the adults and their foraging for, rather than incubating, their young. Counter intuitively, in the study area, where the Rufous Hornero is a recent arrival following deforestation, and where the climate is very different from where it evolved, there seems to be no clear thermal benefits for the birds from their energetically expensive mud nest.

Melanocytic naevi with globular and reticular dermoscopic patterns display distinct BRAF V600E expression profiles and histopathological patterns.

BRAF (v-raf murine sarcoma viral oncogene homologue B) V600E mutations have been detected with high frequency in melanocytic naevi. Few studies have stratified analyses by naevus dermoscopic pattern. To determine the frequency of BRAF V600E expression and histopathological pattern in acquired melanocytic naevi distinguished by a globular vs. reticular dermoscopic pattern. We retrospectively identified histologically proven melanocytic naevi with banal reticular or globular dermoscopic patterns and evaluated BRAF V600E expression using immunohistochemistry. BRAF V600E expression was detected in 11 of 12 globular naevi vs. four of 13 reticular naevi (91·7% vs. 30·1%, P=0·004). A predominantly dermal growth pattern (P<0·001) and the presence of large junctional nests (P=0·017) were each associated with a globular dermoscopic pattern. The presence of either a predominantly dermal growth pattern or large junctional nests was found in 13 of 15 naevi positive for BRAF V600E and in two of 10 naevi negative for BRAF V600E (86·7% vs. 20%, P=0·002). The frequency of BRAF V600E mutations differs in naevi distinguished by unique dermoscopic structures and microanatomical growth patterns. Globular naevi, which most often histologically correspond to a predominantly dermal growth pattern and/or the presence of large junctional nests, are significantly more likely to express BRAF V600E than reticular naevi. These preliminary results require validation, but may directly inform future studies of naevogenesis and melanoma genesis.

Ants under the conditions of an extremely hot summer

Specific features of ant behavior during the extremely hot summer of 2010 were studied, as well as the aftereffects of this season on simple and complex family units of ants in 2011–2012. Simultaneous studies were carried out in southern taiga (Moscow Province, Verkhnaya Klyazma myrmecological protected area) and northern taiga (Arkhangelsk Province, Pinezhskii Nature Reserve). Ants of the genus Formica responded to the extreme heat by (1) changing their foraging patterns; (2) redesigning their nests; (3) rearranging the spatial and functional structure of the colonies. They switched to a bimodal activity pattern with maxima in the morning and in the evening and a prolonged daytime intermission. Along ant roads, there were underground pavilions with dense roofs built of conifer needles and soil. Covers of the same kind appeared over root aphid colonies. The most radical improvement was the construction of a battery of brood chambers underneath the mound. The soil excavated was used for strengthening the mound and restricting the convective heat exchange between the brood chambers and the external environment. The anthill surface was covered with a smooth crusted layer of soil and fine plant debris particles, which protected the nest from the inflow of hot air from without. A portion of the inhabitants of large nests moved to newly built extensions and auxiliary nests. It was only active, non-damaged colonies that could afford these measures and thus survive the heat with minimal loss. Depressed colonies lost the major part of their brood during this time. Furthermore, small secondary colonies that emerged as the result of destructive activity of animals also failed to reassemble due to the summer heat of 2010. The months of heat were followed by a long rainy and cool period, and the colonies that had already been depressed faced critical conditions for preparing for winter. The ants were unable to accumulate lipid reserves sufficient for spring nest heating and rearing of sexuals and workers, which turned out to be an important aftereffect of the 2010 season the following year. Two first generations of workers were absent in almost all the nests. Mass oviposition in F. aquilonia commenced only late in May 2011, whereas the flight of alates did not occur at all because alates of this species are only reared in spring. Consequently, the F. aquilonia colonies had not recovered even by the end of 2012. In F. lugubris and F. polyctena, species that rear sexuals twice a year, there was only late-season alate flight, and yet it allowed their colonies to replenish the pool of ovipositing females and restore the initial colony size by the end of 2012. Other ants, represented by Lasius niger and Myrmica rubra, also modified their nests and foraging patterns during the period of heat. M. rubra suffered the most, so that its abundance and activity remained very low in 2011 as well. Only L. niger, which remained practically unscathed by the heat, successfully completed its annual cycle in 2010. Therefore, one of the 2010 year’s results was a drastic shift in the ratio of nests built by the abovementioned species in favor of L. niger.

Dermoscopic features in different morphologic types of basal cell carcinoma.

Many different phenotypic presentations of basal cell carcinoma (BCC) are possible. This study aims to highlight the similarities and differences in dermoscopic features between different morphologic types of BCC. A prospective observational study was performed using contact polarized dermoscopy to evaluate the presence of various dermoscopic features. Images were evaluated for a range of dermoscopic colors, structures, and vessels. Features were compared according to the histopathologic subtype. Of the 151 BCCs, 39.7% were nodular, 37.7% superficial, 13.9% ulcerated, 3.97% pigmented, 2.65% morpheaform, and 1.99% infiltrative BCCs. The dermoscopic features that showed a highly significant difference (p < .001) in distribution between various histologic groups were large blue-gray ovoid nests, leaf-like areas, arborizing vessels, short fine telangiectasias, annular distribution of telangiectatic vessels, structureless hypopigmentation, annular hypopigmentation, translucency, multiple erosions, and ulceration. A significant difference (p < .05) between evaluated groups was found in structureless hyperpigmentation, arborizing microvessels, milky red background, and pigment network. The results of the study indicate that the combination of relevant dermoscopic features in different morphologic types of BCC depends on the thickness of the tumor, and not on its histologic nature. In addition, dermoscopy was shown to be not particularly useful in identifying which BCCs are more aggressive.

Fisetin inhibits human melanoma cell growth through direct binding to p70S6K and mTOR: Findings from 3-D melanoma skin equivalents and computational modeling

The incidence of melanoma continues to rise. Inspite of treatment advances, the prognosis remains grim once the disease has metastasized, emphasizing the need to explore additional therapeutic strategies. One such approach is through the use of mechanism-based dietary intervention. We previously showed that the flavonoid fisetin inhibits melanoma cell proliferation, in vitro and in vivo. Here, we studied fisetin-mediated regulation of kinases involved in melanoma growth and progression. Time-course analysis in 3-D melanoma constructs that transitioned from radial to vertical growth showed that fisetin treatment resulted in significant decrease in melanocytic lesions in contrast to untreated controls that showed large tumor nests and invading disseminated cells. Further studies in melanoma cultures and mouse xenografts showed that fisetin-mediated growth inhibition was associated with dephosphorylation of AKT, mTOR and p70S6K proteins. In silico modeling indicated direct interaction of fisetin with mTOR and p70S6K with favorable free energy values. These findings were validated by cell-free competition assays that established binding of fisetin to p70S6K and mTOR while little affinity was detected with AKT. Kinase activity studies reflected similar trend with % inhibition observed for p70S6K and mTOR at lower doses than AKT. Our studies characterized, for the first time, the differential interactions of any botanical agent with kinases involved in melanoma growth and demonstrate that fisetin inhibits mTOR and p70S6K through direct binding while the observed inhibitory effect of fisetin on AKT is mediated indirectly, through targeting interrelated pathways.

Thermoregulation strategies in ants in comparison to other social insects, with a focus on red wood ants ( Formica rufagroup).

Temperature influences every aspect of ant biology, especially metabolic rate, growth and development. Maintenance of high inner nest temperature increases the rate of sexual brood development and thereby increases the colony fitness. Insect societies can achieve better thermoregulation than solitary insects due to the former's ability to build large and elaborated nests and display complex behaviour. In ants and termites the upper part of the nest, the mound, often works as a solar collector and can also have an efficient ventilation system. Two thermoregulatory strategies could be applied. Firstly the ants use an increased thermal gradient available in the mound for brood relocation. Nurse workers move the brood according to the thermal gradients to ensure the ideal conditions for development. A precise perception of temperature and evolution of temperature preferences are needed to make the correct choices. A second thermoregulatory strategy used by mound nesting ants is keeping a high temperature inside large nests. The unique thermal and insulation properties of the nest material help to maintain stable conditions, which is the case of the Wood ant genus Formica. Ants can regulate thermal loss by moving nest aggregation and alternating nest ventilation. Metabolic heat produced by ant workers or associated micro organisms is an important additional source of heat which helps to maintain thermal homeostasis in the nest.

Anomalies in insect nest structures at the Garden Well gold deposit: Investigation of mound-forming termites, subterranean termites and ants

Previous research has demonstrated that small mounds of the termite Tumulitermes tumuli (Froggatt) can successfully be used as a geochemical sample medium for detecting Au mineralization concealed beneath transported cover. This finding is in contrast to the use of large mound forming species typically targeted for exploration in northern Australia and Africa. Large areas of Australia not only have small mound forming termites present but also have subterranean termites and ants. Subterranean termites can have large nests hidden sub-surface. When foraging they sheath their food sources with soil in order to create a microclimate. Here we investigate the use of this material along with nest material from an ant species as sampling media for geochemical exploration in the Yilgarn Craton, Western Australia.Samples were collected along a transect at the Garden Well Au deposit in the Duketon Greenstone Belt of the Yilgarn Craton in Western Australia. Elevated Au concentrations (above a background level ~2ppb) were found in all 3 nest structure types over the mineralization. The mound forming termite (T. tumuli), which forms structures to 60cm in height, had up to 7.4ppb Au. The subterranean termite (Schedorhinotermes actuosus) had up to 8.4ppb, in the sheath material, and an ant species (Rhytidoponera mayri) recorded Au up to 24.4ppb, in the nest material. Vertical movement of Au, Cu and Zn from at least 1.4m deep is supported by evidence in the form of XRD studies and mineral grain counts of nests. These show vertical movement of calcite-rich fragments associated with elevated Au.This is the first investigation of the suitability of subterranean termites for use in geochemical exploration and results suggest that they and ants in the same area represent a potentially useful sample media.

Variability of daily nest survival and breeding success in relation to characteristics of Eurasian magpie (Pica pica) nests

Size and structure of birds’ nests can arise from evolutionary trade-offs between benefits, such as insulation from unfavourable conditions, maintenance of eggs or chicks, security against predation, and costs, such as energy spent in construction of the nest and the risk of predation in more visible nests. The relationships between nest characteristics and breeding success and survival probabilities of Eurasian magpie (Pica pica) eggs and nestlings were studied in Baghbadaran, central Iran during the 2008 and 2010 breeding seasons. Nesting success was modelled to assess the relationships between nest parameters and the probability of daily nest survival. Mean clutch and brood size, hatching, fledging and breeding success did not vary significantly between the two years. Mean internal diameter, external diameter, distance to feeding location and distance to open areas varied significantly between the two study years. Daily nest survival rate for both years (2008 and 2010) was 0.98 ± 0.002. Nest size and status of nests, defined as old or newly established nests, were the best factors predicting probabilities of nest survival. Nests with small internal diameters had higher overall nest productivity. Nest height was positively correlated with both fledging success and breeding success. Our results agree with previous findings that have shown that magpie pairs with large nests provided their nestlings with higher quality food compared with pairs with smaller nests and so nest size was an indicator of parental ability. Nest height is also recognized as an important determinant of nest predation, mostly because it may affect nest detectability and accessibility.

Thermoregulation strategies in ants in comparison to other social insects, with a focus on Formica rufa

Temperature influences every aspect of ant biology, especially metabolic rate, growth and development. Maintenance of high inner nest temperature increases the rate of sexual brood development and thereby increases the colony fitness. Insect societies can achieve better thermoregulation than solitary insects due to the former’s ability to build large and elaborated nests and display complex behaviour. In ants and termites the upper part of the nest, the mound, often works as a solar collector and can also have an efficient ventilation system. Two thermoregulatory strategies could be applied. Firstly the ants use an increased thermal gradient available in the mound for brood relocation. Nurse workers move the brood according to the thermal gradients to ensure the ideal conditions for development. A precise perception of temperature and evolution of temperature preferences are needed to make the correct choices. A second thermoregulatory strategy used by mound nesting ants is keeping a high temperature inside large nests. The unique thermal and insulation properties of the nest material help to maintain stable conditions, which is the case of the Wood ant genus Formica. Ants can regulate thermal loss by moving nest aggregation and alternating nest ventilation. Metabolic heat produced by ant workers or associated micro organisms is an important additional source of heat which helps to maintain thermal homeostasis in the nest.

Manna from heaven: Refuse from an arboreal ant links aboveground and belowground processes in a lowland tropical forest

Aboveground consumers can shape belowground processes by serving as conduits for resources. Social insects dominate in terms of biomass in tropical forests, but compared to studies on large mammals, or aggregate solitary insects, we know relatively little about the role of social insects as nutrient conduits particularly in complex environments like tropical forests. Social insects like ants in the tropical forest canopy can connect aboveground and belowground food webs by producing a nutrient stream (excreta) from large, long‐lived and stationary nests. The excreta, in turn, would create enduring spatial heterogeneity in the forest floor. Here we evaluate this scenario in a lowland Neotropical forest using Azteca trigona, a dominant canopy ant that feeds on honeydew and insects and rains refuse out of its hanging nests onto the leaf litter below. We investigate decomposition rates and detrital communities associated with areas near nests versus 10 m away. Further, we directly test refuse's impact on decomposition and detrital communities in a common garden experiment. Relative to leaf litter, refuse is enriched 7‐fold in P, 23‐fold in K, and 3‐fold in N, all elements shown to limit decomposition in this forest. Accordingly, both artificial substrates and natural leaf litter substrates decomposed over 1.5‐ and 1.2‐fold faster respectively below A. trigona nests and areas under nests supported more invertebrate detritivores and predators compared to controls 10 m away. These decomposition results were replicated in a 6‐wk common garden experiment, but the changes in detrital invertebrate composition were not. Canopy ants like A. trigona act as dependable nutritional conduits to patches of the forest floor, transferring significant quantities of aboveground exudates and necromass. The general capacity for such social insect colonies to generate ecosystem heterogeneity remains an open question.

Equilibrium-nonequilibrium states of ornithogenous geosystems in the north pacific islands

An analysis is made of the issue related to the structural-functional organization of ornithogenous geosystems evolving in islands with large maritime colonial bird nest clusters. It is shown that under moderate ornithogenous pressure (Talan Island), the long-term vital activity of birds acts as an ecological factor identical to light, heat and atmospheric precipitation, and the geosystem is in an equilibrium state. In the case of a strong impact exceeding the stability threshold (Shelikan Island), the geosystem switches to a nonequilibrium state, which is accompanied by a degradation of the soil-vegetation cover, a mass extinction of ornithophobic plant species, a change in soilformation directedness, and by a most dramatic development of erosion processes.

Mandibular and postpharyngeal gland secretions of &lt;i&gt;Acromyrmex landolti&lt;/i&gt; (Hymenoptera: Formicidae) as chemical cues for nestmate recognition

Nestmate recognition is fundamental for the cohesiveness of the colony in social insects. Acromyrmex landolti is a higher Attini, a leaf-cutter ant with largest nest and morphological castes. We studied the location of the recognition signal of A. landolti on the whole ant body, the isolation effect on the capacity of nestmate recognition, and the role of the mandibular (MG) and post-pharyngeal glands (PPG) as putative sources for chemical recognition signals in this species. We performed behavioral bioassays and chemical analyses of MG and PPG glands; MG volatiles in different castes were also characterized. In order to determine the occurrence of nestmate recognition signals, behavioral tests were performed for which the whole body, body parts or gland extracts from a nestmate and an alien worker ant, were placed on the central axis of an active field trail. Besides, the isolation effect of the nestmate chemical signal persistence was evaluated by repeating the experiments with whole ant bodies after 12 h, 24 h and 48 h of isolation. The agonistic behavior of the ants on the trail was classified as inspection, threatening and biting. Gland volatiles were obtained by headspace solid phase microextraction, and PPG by solid sample analyses; and chemical analyses were performed using gas chromatography-mass spectrometry. Workers performed agonistic behaviors more frequently towards non-nestmate whole bodies, body parts and gland extracts, primarily those from the post-pharyngeal glands. Nestmate thoraces odorized with alien extracts were also recognized from aliens. Nestmate recognition ability persists for 12 h and 24 h after isolation, but decreases after 48 h, suggesting that the chemical signal changes over time. Inter-colonial chemical analyses showed no differences in the PPG hydrocarbon profiles, while the relative proportions of MG compounds showed significant differences between colonies. These results showed that nestmate recognition was achieved by MG volatiles. Possibly, the PPG secretion works as a matrix that absorbs MG volatiles. We report, for the first time, some mandibular gland compounds for the genus Acromyrmex and for the tribe Attini group.

Preparation of Europe's largest nest of dinosaur eggs

In the present work we describe the whole process of extraction and preparation of a large nest of dinosaur eggs. The dinosaur nest found in the locality of Pinyes is the largest one discovered in Europe and the excavation and preparation processes used were very long and complex. The discovery of this nest took place in the year 2005. A new campaign of excava- tions, in 2007, placed particular emphasis on the importance of this nest and it was not until the year 2009 that it could be extracted without damaging the integrity of the fossil. Its preparation, during 2009-2010, has allowed the researchers of the Mesozoic Group (of the ICP) to study it in depth. The investigation has emphasized the rele- vancy of the finding worldwide, since it reveals new information on the reproduc- tive behavior of sauropods. The use of excavation techniques based on the acquisi- tion of three-dimensional data helped during the preparation process, and it has allowed very precise results to be obtained regarding the interpretation of their nests and the way these dinosaurs laid theireggs. These results indicate that the nest con- tained 28 eggs, many more than other nests found in Europe and India. The eggs are positioned in three superimposed levels, and the nest shows an asymmetric, concave and elongated morphology when it is observed in lateral view. The nest is currently exhibited in the Dinosfera Museum, Coll de Narg�, Alt Urgell (Spain).

Dermoscopy and Confocal Microscopy of Nested Melanoma of the Elderly

Nested melanoma of the elderly is a newly identified histopathologic variant of superficial spreading melanoma, characterized by intraepidermal large nests. However, the clinical, dermoscopic, and confocal aspects have been depicted only partially. In our cases series, nested melanoma was a flat, irregularly shaped lesion with variably pigmented and irregularly distributed globules on dermoscopic examination. Confocal microscopy revealed the presence of a "clod" pattern made of large compact nests with variable atypia. These findings correlated well with histopathologic features. Nested melanoma of the elderly should be included in the differential diagnosis when a flat pigmented lesion, showing dermoscopically an irregular globular pattern, is seen in a patient older than 60 years.

Nested Melanoma, A Newly Defined Entity

Three cases of nested melanoma have been documented in detail by Longo and colleagues.1 Clinically, we see flat, asymmetrically shaped lesions with irregular pigmentation, measuring 5 to 10 mm in diameter, on heavily sun-damaged skin, which are highly suggestive of melanoma. Dermoscopy reveals irregular dots and globules, a multicomponent overall structure, irregular blotches, and sometimes atypical pigment network, which are all indicative for melanoma. Confocal microscopy did not add much, revealing the presence of a �clod� pattern made of large compact nests with variable atypia. Taken all together, we would clinically diagnose superficial spreading melanoma in heavily sun-damaged skin.

Coevolution of the Tumor Microenvironment Revealed by Quantum Dot-Based Multiplexed Imaging of Hepatocellular Carcinoma

This study aimed to provide new insights into the mechanisms of hepatocellular carcinoma (HCC) invasion by simultaneously imaging tumor cells and major components of the tumor microenvironment. Formalin-fixed paraffin-embedded human HCC tissues were studied by conventional immunohistochemistry and quantum dot-based multiplexed imaging to reveal type IV collagen, LOX and tumor angiogenesis. Type IV collagen degradation and repatterning in the extracellular matrix (ECM) was a continuous process, making the ECM harder, although more fragile and less resistant to cancer invasion. The distribution of LOX among cancer nests was heterogeneous, with higher expression in small cancer nests and lower expression in large cancer nests. LOX expression in cancer cells was associated with rigid stroma and tumor angiogenesis. Tumor angiogenesis occurred with type IV collagen presence. At the cancer invasion front, the ECM was hydrolyzed, with the prominent linear reorientation of type IV collagen surrounding cancer nests adjacent to neovessels. The visualization of the temporal-spatial relationship between type IV collagen, LOX and tumor angiogenesis revealed the coevolution process of HCC cells and their microenvironment, emphasizing an active role of the ECM during cancer invasion.