Adjacent Epidermis Research Articles

Immunohistochemical Analyses of Monkeypox Skin Lesions with MPXV A29 and A35 Antibodies: A Novel Insight for Clinical-Histopathological Forms.

The aim of this study was to describe the clinical, histopathological, and immunohistochemical characteristics of MPX and offer meaningful insights into the clinicopathology of MPX. We recruited eight men who had sex with men diagnosed with MPX based on positive results from MPX Virus (MPXV)-specific polymerase chain reaction. Skin biopsies were obtained from four selected lesions, including typical and atypical lesions. Histopathological examinations of atypical solitary ulceration revealed infiltrating inflammatory cells predominantly composed of plasma cells and lymphocytes, forming a "sleeve" around the superficial vessels of the dermis. These features might be misinterpreted as indicative of cutaneous syphilis infection. Meanwhile, typical pustular lesions displayed central necrotic epidermis accompanied by perivascular inflammatory infiltrate dominated by neutrophils, as well as ballooning and reticular degeneration of keratinocytes. Additionally, multinucleated keratinocytes and eosinophilic cytoplasmic inclusions known as Guarnieri's bodies were also observed. Importantly, this study represented the pioneering report on immunohistochemical detection of MPXV A29 and A35 proteins in skin lesions, distinguishing it from previous studies that focused on detecting vaccinia virus protein. The anti-MPXV A29 antibody exhibited robust cytoplasmic staining specifically within affected keratinocytes in both adjacent epidermis and hair follicles, thereby it could contribute to the diagnosis of MPX, especially for cases with atypical skin lesions.

Suspicious Papule on Lower Vermillion Border

ABSTRACT Molluscum contagiosum (MC) is a highly contagious, cutaneous infection caused by a double-stranded DNA poxvirus. Mollusca are characterized by a firm, dome-shaped, flesh-colored, pearly papule with a white, umbilicated center. Generally, lesions occur in clusters and range in size from 1 to 5 millimeters. Although unusual and infrequent, MC occurring in an epidermal inclusion cyst has been reported. This case involves an 83-year-old woman with a flesh-colored, slightly tender papule on the right lower vermillion border, which had been enlarging over several months. Histopathology showed prominent molluscum bodies present in the adjacent epidermis and focally lining the central epidermal cyst. The findings observed in this case support the hypothesized pathophysiological co-inoculation theory for the development of molluscum-infected epidermal inclusion cysts. This is clinically significant given the infectivity of cyst contents and the potential for direct inoculation of the cyst. Given its rarity, treatment protocols for epidermal inclusion cysts containing MC have not been established. However, management requires care to avoid viral transmission.

Role of asprosin and meteorin-like peptide in progression of actinic keratosis to squamous cell carcinoma

ABSTRACT Squamous cell carcinoma (SCC) often develops from an underlying premalignant lesion. Factors that affect the progression of actinic keratosis (AK) to invasive SCC are not fully known. Asprosin (ASP) and meteorin-like peptide (METRNL) are adipokines that are involved primarily in glucose metabolism. We investigated the expression of ASP and METRNL in AK and SCC to evaluate the role of these adipokines in the development of SCC. We used 15 SCC specimens, 12 AK specimens and 12 healthy control skin specimens. ASP and METRNL protein expression in tumor and surrounding tissue was evaluated using immunohistochemistry. ASP expression in tumor tissue was significantly greater in the SCC group than in the control and AK groups, but it did not differ significantly between the AK and control groups. A positive correlation was observed for both ASP and METRNL expressions between tumor tissue and adjacent epidermis, hair follicles, sebaceous gland, eccrine gland, inflammatory cells and vascular structures. ASP and METRNL may exert pro-tumor effects toward development of invasive SCC. The expression intensity of ASP and METRNL can be used as a biomarker of risk of progression to SCC.

Pathology of short-term dorsal fin tag-attachments in tagged and re-stranded short-beaked common dolphins Delphinus delphis on Cape Cod, MA

Odontocetes are difficult to study in the wild, making tagging and remote tracking a valuable practice. However, evaluations of host responses at tagging sites have been primarily limited to visual observations in the field. Here we explore the macro- and microscopic pathology of dorsal fin tag attachments in 13 stranded and released short-beaked common dolphins Delphinus delphis from Cape Cod, MA that later re-stranded and died or were euthanized 1-28 d post-tagging. Tags were attached to stranded dolphins’ dorsal fins using 2 methods: core biopsy or piercing. Grossly, the piercing method resulted in epidermal compression into the dermis. One tag site had a necrotic border 28 d after application. Grossly, the biopsy method resulted in minimal to no tissue reaction. Two tag sites had granulation tissue accumulation 4 and 12 d after tagging. Histopathologic findings for all tag types and animals consisted of focal epithelial loss, dermal edema, perivascular edema, inflammation and hyperplasia, and inter- and extracellular edema in the adjacent epidermis. Minor expected pathological changes given the procedure were also observed: superficial epidermal necrosis in 3 cases, and superficial bacterial colonization in 2 cases. There was no evidence of sepsis and tagging was not related to cause of re-stranding or death in any case. These gross and histopathologic findings support previous observational conclusions in small delphinids that with appropriate sterile technique, the impacts of single pin dorsal fin tagging on the animal can be minimal and localized. Of the 2 methods, core biopsy may be a better tagging method.

Expression of Hedgehog Signaling Pathway Proteins in Basal Cell Carcinoma: Clinicopathologic Study.

Basal cell carcinoma (BCC) is the most common type of cancer with a growing incidence rate over recent decades. The increasing economic burden and incidence of BCC have generated major interest in developing targeted therapies for this disease. The critical role of the Hedgehog (Hh) pathway in the pathogenesis of BCC has become evidently demonstrated. The purpose of this study was to observe the expression of PTCH1 and Gli1 in BCC and further evaluate their relationship with clinicopathological features. This retrospective study included 84 patients with BCC. Information of 84 patients with pathologically diagnosed BCC (including location, sex, tumor size, pathological type, and depth of invasion) were collected, and tissue paraffin blocks were collected for immunohistochemical staining. Western blot analysis for PTCH1 and Gli1 were also performed. The staining intensity and percentage of stained cells were expressed as a histochemical score (HSCORE). PTCH1 and Gli1 were overexpressed in BCC compared with adjacent normal epidermis. Our study found that the expression of PTCH1 and Gli1 in BCC in exposed sites was significantly higher than in non-exposed sites. Moreover, no significant difference was observed in sex, Breslow thickness, tumor size or pathological type (P>0.05). PTCH1 and Gli1 were overexpressed in BCC. Higher PTCH1 and Gli1 expression were in exposed sites lesions. Our study suggests that UV radiation may be associated with aberrant activation of the Hh-PTCH1-Gli1 intercellular signaling pathway in BCC. The molecular mechanism of UV-related PTCH1 and Gli1 differential expression deserves more rigorous research in the future.

The Lateral Epidermis Actively Counteracts Pulling by the Amnioserosa During Dorsal Closure.

Dorsal closure is a prominent morphogenetic process during Drosophila embryogenesis, which involves two epithelial tissues, that is, the squamous amnioserosa and the columnar lateral epidermis. Non-muscle myosin II-driven constriction in the amnioserosa leads to a decrease in the apical surface area and pulls on the adjacent lateral epidermis, which subsequently moves dorsally. The pull by the amnioserosa becomes obvious in an elongation of the epidermal cells, especially of those in the first row. The contribution of the epidermal cell elongation has remained unclear to dorsal closure. Cell elongation may be a mere passive consequence or an active response to the pulling by the amnioserosa. Here, we found that the lateral epidermis actively responds. We analyzed tensions within tissues and cell junctions by laser ablation before and during dorsal closure, the elliptical and dorsal closure stages, respectively. Furthermore, we genetically and optochemically induced chronic and acute cell contraction, respectively. In this way, we found that tension in the epidermis increased during dorsal closure. A correspondingly increased tension was not observed at individual junctions, however. Junctional tension even decreased during dorsal closure in the epidermis. We strikingly observed a strong increase of the microtubule amount in the epidermis, while non-muscle myosin II increased in both tissues. Our data suggest that the epidermis actively antagonizes the pull from the amnioserosa during dorsal closure and the increased microtubules might help the epidermis bear part of the mechanical force.

The Immunoglobulin Superfamily Member Basigin Is Required for Complex Dendrite Formation in Drosophila

Coordination of dendrite growth with changes in the surrounding substrate occurs widely in the nervous system and is vital for establishing and maintaining neural circuits. However, the molecular basis of this important developmental process remains poorly understood. To identify potential mediators of neuron-substrate interactions important for dendrite morphogenesis, we undertook an expression pattern-based screen in Drosophila larvae, which revealed many proteins with expression in dendritic arborization (da) sensory neurons and in neurons and their epidermal substrate. We found that reporters for Basigin, a cell surface molecule of the immunoglobulin (Ig) superfamily previously implicated in cell-cell and cell-substrate interactions, are expressed in da sensory neurons and epidermis. Loss of Basigin in da neurons led to defects in morphogenesis of the complex dendrites of class IV da neurons. Classes of sensory neurons with simpler branching patterns were unaffected by loss of Basigin. Structure-function analyses showed that a juxtamembrane KRR motif is critical for this function. Furthermore, knock down of Basigin in the epidermis led to defects in dendrite elaboration of class IV neurons, suggesting a non-autonomous role. Together, our findings support a role for Basigin in complex dendrite morphogenesis and interactions between dendrites and the adjacent epidermis.

Precise measurement of cutaneous squamous cell carcinoma thickness

To the Editor: Mortality and metastatic rates of cutaneous squamous cell carcinoma (cSCC) correlate with tumor invasion1 but current guidelines for measuring cSCC are inconsistent.2-4 The eighth American Joint Committee Cancer recommends measuring from the top of the adjacent normal epidermis, or “shoulder” of the tumor, to the base.2 The College of American Pathologists recommends measuring at a right angle from overlying or adjacent normal epidermis to the tumor base, or from the ulcer base to the tumor base if the cSCC is completely ulcerated.

Contiguous squamous proliferations in syringocystadenoma papilliferum: A retrospective study of 14 cases.

Syringocystadenoma papilliferum is a benign adnexal neoplasm. Contiguous squamous proliferation has been rarely described in syringocystadenoma papilliferum. This study aimed to evaluate the spectrum and pathogenesis of contiguous squamous proliferation in syringocystadenoma papilliferum. All cases of syringocystadenoma papilliferum diagnosed over the past 12 years were screened for contiguous squamous proliferation. Cases with associated nevus sebaceous were excluded from the study. Immunohistochemistry for GATA3, CK7, BRAFV600E and p16 was performed. PCR for human papilloma virus, type 16 and 18, was carried out. Of a total of 30 cases, 14 cases showed associated contiguous squamous proliferation which included four cases of verrucous hyperplasia, six cases with papillomatosis, two cases with mild squamous hyperplasia and one case each of Bowen's disease and squamous cell carcinoma. In the cases with non-neoplastic contiguous squamous proliferations, the squamous component did not express CK7 or GATA3. However, the squamous component of premalignant and malignant lesions expressed CK7 and GATA3 concordant with the adenomatous component. BRAF was positive in adenomatous component in five cases while the contiguous squamous proliferation component was negative for BRAF in all but one case. p16 was negative in both components of all cases and PCR for human papilloma virus was negative in all cases. Due to the rarity of disease, the sample size of our study was relatively small with two cases in the 2nd group, that is, syringocystadenoma papilliferum with malignant contiguous squamous proliferation. Detailed molecular studies such as gene sequencing were not performed. Syringocystadenoma papilliferum with contiguous squamous proliferation is underreported, and most commonly displays verrucous hyperplasia. The premalignant and malignant contiguous squamous proliferations likely arise from syringocystadenoma papilliferum while the hyperplastic contiguous squamous proliferations likely arise from the adjacent epidermis. Relationship with high-risk human papilloma virus is unlikely. However, further molecular analysis of larger number of cases is required to establish the pathogenesis.

Genomic Progression of Precancerous Actinic Keratosis to Squamous Cell Carcinoma

The mechanism underlying the progression of actinic keratosis (AK) and cutaneous squamous cell carcinoma (SCC) in situ (SCCIS) to SCC remains unclear. To investigate this, we performed regional microdissection and targeted deep sequencing in SCC (n= 10) and paired adjacent sun-damaged epidermis (SE)/AK/SCCIS (n= 13) samples to detect mutations and copy number alterations. Most (11/13) SE/AK/SCCIS tissues harbored ≥1 driver alterations, indicating their precancerous nature. All pairs except one showed genome architectures representing the genomic progression of SE/AK/SCCIS to SCC with common trunks and unique branches (seven parallel and five linear progression cases). SE/AK/SCCIS tissues tended to harbor lower mutation/copy number alteration burdens than SCC tissues, but most of them had driver mutations, including NOTCH1 and TP53 mutations. SCC-specific genomic alterations included TP53, PIK3CA, FBXW7, and CDKN2A mutations and an MYC copy number gain, but they were heterogeneous among cases, suggesting that a single gene or pathway does not explain the progression of AK to SCC. In multiregion analyses of AK lesions, only some AK samples were related to SCC. In conclusion, the SE/AK/SCCIS genomes may have previously acquired truncal driver alterations, such as NOTCH1 and TP53 mutations, which promote parallel or linear progression to SCC on an acquisition of additional genomic alterations.

Fundamentalin vitro3D human skin equivalent tool development for assessing biological safety and biocompatibility – towards alternative for animal experiments

Nowadays, human skin constructs (HSCs) are required for biomaterials, pharmaceuticals and cosmeticsin vitrotesting and for the development of complex skin wound therapeutics.In vitrothree-dimensional (3D) dermal-epidermal based interfollicular, full-thickness, human skin equivalent (HSE) was here developed, recapitulating skin morphogenesis, epidermal differentiation, ultra-structure, tissue architecture, and barrier function properties of human skin. Different 3D cell culture conditions were tested to optimize HSE maturation, using various commercially available serum/animal component-free and/or fully defined media, and air-liquid interface (ALI) culture. Optimized culture conditions allowed the production of HSE by culturing normal human dermal fibroblasts (NHDFs) for 5–7 days in CELLnTEC-Prime Fibroblast (CnT-PR-F) medium and then culturing normal human epidermal keratinocytes (NHEKs) for 3 days in CELLnTEC-Prime Epithelial culture (CnT-PR) medium on them. Co-culture was then submerged overnight in CELLnTEC-Prime-3D barrier (CnT-PR-3D) medium to stimulate cell-cell contact formation and finally placed at ALI for 15–20 days using CnT-PR-3D medium. Histological analysis revealed uniform distribution of NHDFs in the dermal layer and their typical elongated morphology with filopodia. Epidermal compartment showed a multi-layered structure, consisting of stratum basale, spinosum, granulosum, and corneum. NHDFs and keratinocytes of basal layer were positive for the proliferation marker Kiel 67 (Ki-67) demonstrating their active state of proliferation. The presence of typical epidermal tissue proteins (keratins, laminins, filaggrin, loricin, involucrin, and β-tubulin) at their correct anatomical position was verified by immunohistochemistry (IHC). Moreover, transmission electron microscopy (TEM) analyses revealed basement membrane with lamina lucida, lamina densa, hemidesmosomes and anchoring fibers. The epidermal layers showed abundant intracellular keratin filaments, desmosomes, and tight junction between keratinocytes. Scanning electron microscopy (SEM) analyses showed the interwoven network of collagen fibers with embedded NHDFs and adjacent stratified epidermis up to the stratum corneum similar to native human skin. HSE physiological static contact angle confirmed the barrier function. The developed HSE represents a fundamentalin vitrotool to assess biocompatibility of biomaterials, pharmacotoxicity, safety and effectiveness of cosmetics, as well as to investigate skin biology, skin disease pathogenesis, wound healing, and skin infection.

Whole-Exome and Transcriptome Analysis of UV-Exposed Epidermis and Carcinoma In Situ Reveals Early Drivers of Carcinogenesis

Squamous cell carcinoma in situ (SCCIS) is a prevalent precancerous lesion that can progress to cutaneous squamous cell carcinoma. Although SCCIS is common, its pathogenesis remains poorly understood. To better understand SCCIS development, we performed laser captured microdissection of human SCCIS and the adjacent epidermis to isolate genomic DNA and RNA for next-generation sequencing. Whole-exome sequencing identified UV-signature mutations in multiple genes, including NOTCH1-3 in the epidermis and SCCIS and oncogenic TP53 mutations in SCCIS. Gene families, including SLFN genes, contained UV/oxidative-signature disruptive epidermal mutations that manifested positive selection in SCCIS. The frequency and distribution of NOTCH and TP53 mutations indicate that NOTCH mutations may precede TP53 mutations. RNA sequencing identified 1,166 differentially expressed genes; the top five enriched gene ontology biological processes included (i) immune response, (ii) epidermal development, (iii) protein phosphorylation, (iv) regulation of catalytic activity, and (v) cytoskeletal regulation. The NEURL1 ubiquitin ligase, which targets Notch ligands for degradation, was upregulated in SCCIS. NEURL1 protein was found to be elevated in SCCIS suggesting that increased levels could represent a mechanism for downregulating Notch during UV-induced carcinogenesis. The data from DNA and RNA sequencing of epidermis and SCCIS provide insights regarding SCCIS formation.

Tumour-infiltrating Langerhans cells in non-melanoma skin cancer, a clinical and immunohistochemical study.

Non-melanoma skin cancer, including basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) represents 78.5% of all skin malignant tumours in Egypt. Dendritic cells can be found in almost all human tumours, they play an important role in antitumour immunity. The aim of the present study was to evaluate the percentage of Langerhans cells using CD1a in non-melanoma skin cancer, including BCC and SCC and to correlate this percentage with their clinicopathological features. The current study was performed on surgically excised specimens of 41 patients presented with non-melanoma skin cancer (26 BCC and 15 SCC) and 16 healthy volunteer control subjects. The mean and median percentage of Langerhans cells were higher in normal epidermis of control compared to malignant tumour tissue (p < 0.0001) and adjacent epidermis overlying malignant tumour tissue (p = 0.007). Langerhans cells were significantly seen in BCC cases more than SCC (p = 0.035) and they were seen in facial lesions more than those arising from other sites (p = 0.007). The reduction of Langerhans cells is a way for non-melanoma skin cancer to develop and progress. Marked reduction of Langerhans cells in SCC compared to BCC could refer to their role as a barrier against metastasis.

An3-Mediated Compensation Is Dependent on a Cell-Autonomous Mechanism in Leaf Epidermal Tissue.

Leaves are formed by coordinated growth of tissue layers driven by cell proliferation and expansion. Compensation, in which a defect in cell proliferation induces compensated cell enlargement (CCE), plays an important role in cell-size determination during leaf development. We previously reported that CCE triggered by the an3 mutation is observed in epidermal and subepidermal layers in Arabidopsis thaliana (Arabidopsis) leaves. Interestingly, CCE is induced in a non-cell autonomous manner between subepidermal cells. However, whether CCE in the subepidermis affects cell size in the adjacent epidermis is still unclear. We induced layer-specific expression of AN3 in an3 leaves and found that CCE in the subepidermis had little impact on cell-size determination in the epidermis, and vice versa, suggesting that CCE is induced in a tissue-autonomous manner. Examination of the epidermis in an3 leaves having AN3-positive and -negative sectors generated by Cre/loxP revealed that, in contrast to the subepidermis, CCE occurred exclusively in AN3-negative epidermal cells, indicating a cell autonomous action of an3-mediated compensation in the epidermis. These results clarified that the epidermal and subepidermal tissue layers have different cell autonomies in CCE. In addition, quantification of cell-expansion kinetics in epidermal and subepidermal tissues of the an3 showed that the tissues exhibited a similar temporal profile to reach a peak cell-expansion rate as compared to wild type. This might be one feature representing that the two tissue layers retain their growth coordination even in the presence of CCE.

Metal chelation reduces skin epithelial inflammation and rescues epithelial cells from toxicity due to thermal injury in a rat model.

BackgroundOne of the most pervasive complications of burn injury is wound progression, characterized by continuous tissue destruction in untreated wounds, which leads to wound infection, inflammation, oxidative stress and excessive scar formation. We determined whether additional tissue destruction could be attenuated with Livionex formulation (LF) lotion, which contains a metal-chelating agent and reduces inflammation in burn wounds.MethodsWe subjected male Sprague Dawley rats to a 2% total body surface area (TBSA) burn using a brass comb model and topically applied LF lotion (containing ethylenediaminetetraacetic acid and methyl sulfonyl methane) to the affected area every 8 hours over 3 days. Inflammatory cytokine levels, cell apoptosis and wound healing were compared in LF lotion-treated and untreated rats. Statistical analysis was performed using a one-way analysis of variance in conjunction with Tukey’s post-hoc test.ResultsSerum inflammatory cytokines were not detectable after 3 days, suggesting that small burn wounds induce only an immediate, localized inflammatory response. Microscopy revealed that LF lotion improved burn site pathology. Deoxynucleotidyl transferase biotin-d-UTP nick-end labeling staining showed reduced cell death in the LF-treated samples. LF lotion prevented the spread of tissue damage, as seen by increased amounts of Ki-67-positive nuclei in the adjacent epidermis and hair follicles. Tumor necrosis factor-alpha, interleukin-6 and inducible nitric oxide synthase levels in LF-treated skin sections from burned rats were comparable to the levels observed in unburned control sections, indicating that LF lotion reduces inflammation in and around the burn site.ConclusionsThese results establish LF lotion as a therapeutic agent for reducing inflammatory stress, cell death and tissue destruction when applied immediately after a burn injury. Further studies of LF lotion on large TBSA burns will determine its efficacy as an emergency treatment for reducing long-term morbidity and scarring.

Clinical and Histopathological Findings in Patients with Follicular Dermatoses: All Skin Diseases Starts in the Hair Follicles as New Hypothesis

Background: Follicular dermatoses are group of skin diseases characterised by follicular lesions during the course of the disease. Objective: To gather all skin diseases where there is follicular lesions to be evaluated in order to reach the hypothesis that hair follicles are the most principal target area in the etiopathogenesis of these skin disorders. Patients and Methods: This is a descriptive, clinical and histopathological study that was carried out at the Department of Dermatology, Baghdad Teaching Hospital, Medical City, and Baghdad, Iraq during the period from November 2018 to August 2019. Sixty patients with different follicular dermatoses were enrolled and all socio- demographic data related to the disease was obtained from each patient, in addition to physical examination was performed for each patient. Biopsies were taken from 40 patients, for histopathological evaluation. Results: Sixty patient, were included in this study, 35 patients males and 25 patients females with male to female ratio 1.4:1. Their ages ranged from 1-80(30.2 ± 16.96) years. All patients had follicular lesions. The histopathological results showed: perifollicular lymphocytes, follicular invasion and degeneration, follicular plugging, fibrous tract remnant, perifollicular melanophages and absent melanin pigment in the epidermis of patients with vitiligo. Conclusion: The result of the present study showed that all skin diseases start in the hair follicles and might spread to involve the proper epidermis, and the lesions could be microscopic or visible to the naked eye. The hair follicles have many anatomical and immunological privileges that make it easy to be an early target for any cutaneous pathological process. Hence these findings are in support of new hypothesis that say: all skin diseases starts in the hair follicles and then spread to attack the adjacent proper epidermis

Follicular Dermatoses in Iraqi Patients (Clinical and Histopathological Evaluation)

Background: Follicular dermatoses are skin diseases that involved the hair follicle either early or during the course of the disease. Objective: To collect a number of dermatoses where there is follicular involvement, to be studied and analysed in order to reach a conclusion that hair follicles are the most important target area in the pathogenesis of these dermatoses. Patients and Methods: This is a descriptive, clinical and histopathological study that was carried out at the Centre of Dermatology and Venereology, Baghdad Teaching Hospital, Medical City, Baghdad, Iraq during the period from December 2017 to August 2019. Forty patients with follicular dermatoses were included and all socio- demographic data related to the disease was obtained from each patient, in addition to clinical examination was performed for each patient. Lesional biopsies were done for 20 patients, for histopathological examination by Haematoxylin and Eosin (H&E). Results: The mean age ± SD was 30.2±16.96 years, 25 patients were males and 15 patients were females, the clinical diagnosis of follicular diseases was established for all skin diseases included in the present work. The histopathological findings of lesional biopsies were mainly: perifollicular lymphocytes, follicular invasion and degeneration, follicular plugging, fibrous tract remnant, perifollicular melanophages and hair follicle cyst. Conclusion: The result of the present study does encourage us to suggest that almost all skin diseases included in this study start initially on the hair follicle and then spread to involve the adjacent epidermis.

STAT3, STAT5A, STAT5B and STAT6 proteins are overexpressed in human basal cell carcinoma.

The molecular pathogenesis of basal cell carcinoma (BCC) is still not precisely described and is the subject of ongoing studies. The role of signal transducers and activators of transcription (STATs) in human epithelial carcinogenesis has been poorly investigated, but in the era of studies on inhibitors targeting STAT proteins this topic seems worth exploring. Increased expression of STAT3 in human nonmelanoma skin cancer (NMSC) has been confirmed in a few studies, but to our knowledge, expression of STAT5A, STAT5B and STAT6 in BCC has not been previously evaluated. To measure expression of STAT3, STAT5A, STAT5B and STAT6 expression in different histopathological subtypes of human BCC and its correlation with selected clinical variables. Immunohistochemistry was used to assess 60 BCC tumour specimens [20 superficial (s)BCCs, 20 nodular (n)BCCs and 20 infiltrative (i)BCCs] and to compare with specimens of healthy skin. There was no significant difference in age or sex between the three groups of patients with BCC. As many tumours showed heterogeneity of staining, the H-score system was applied to calculate the intensity of immunoexpression. Expression of STAT3, STAT5A, STAT5B and STAT6 was observed in all histopathological subtypes of BCC, and was stronger than the expression within the adjacent epidermis and also stronger than the expression within the epidermis in the healthy control group. Statistical analysis revealed no significant differences in mean H-scores calculated for sBCCs, nBCCs and iBCCs. There were no statistically significant associations between STAT3, STAT5A, STAT5B and STAT6 expression and patient sex/age, and tumour size/site. Our results confirm a possible role of STATs in the pathogenesis of BCC and should encourage future investigations on the possible therapeutic implications of this finding.

Exploring Differential Connexin Expression across Melanocytic Tumor Progression Involving the Tumor Microenvironment.

The incidence of malignant melanoma, one of the deadliest cancers, continues to increase. Here we tested connexin (Cx) expression in primary melanocytes, melanoma cell lines and in a common nevus, dysplastic nevus, and thin, thick, and metastatic melanoma tumor progression series involving the tumor microenvironment by utilizing in silico analysis, qRT-PCR, immunocyto-/histochemistry and dye transfer tests. Primary melanocytes expressed GJA1/Cx43, GJA3/Cx46 and low levels of GJB2/Cx26 and GJC3/Cx30.2 transcripts. In silico data revealed downregulation of GJA1/Cx43 and GJB2/Cx26 mRNA, in addition to upregulated GJB1/Cx32, during melanoma progression. In three melanoma cell lines, we also showed the loss of GJA1/Cx43 and the differential expression of GJB1/Cx32, GJB2/Cx26, GJA3/Cx46 and GJC3/Cx30.2. The dominantly paranuclear localization of connexin proteins explained the ~10–90 times less melanoma cell coupling compared to melanocytes. In melanocytic tumor tissues, we confirmed the loss of Cx43 protein, fall of cell membrane and elevated paranuclear Cx32 with moderately increased cytoplasmic Cx26 and paranuclear Cx30.2 positivity during tumor progression. Furthermore, we found Cx43, Cx26 and Cx30 proteins upregulated in the melanoma adjacent epidermis, and Cx43 in the tumor flanking vessels. Therefore, differential connexin expression is involved in melanocytic tumor progression where varying connexin isotypes and levels reflect tumor heterogeneity-related bidirectional adaptive interactions with the microenvironment.

Роль белка Cbx7 в процессах регенерации поврежденного эпидермиса

The understanding of alterations of epigenetic mechanisms in the development of many disorders, such as impaired wound healing, cancer and aging is increasingly seen as a priority in biomedical research. This project aimed to investigate the expression of Polycomb group protein Cbx7 in the wound epithelium and its role in the migration of keratinocytes after wounding. Cbx7 expression was determined in mouse wound samples collected at early stages of wound healing and analyzed using PCR and immunofluorescent detection methods. For cell migration analysis, HaCaT cell line was treated with a specific small molecule inhibitor MS37452 followed by the scratch assay. Analyses of Cbx7 expression revealed a significant downregulation of Cbx7 mRNA and protein levels in the wound epithelium in comparison to the unwounded or adjacent epidermis. Inhibition of Cbx7 using MS37452 showed a significant acceleration of cell migration in vitro. These data suggest that a decrease in Cbx7 is necessary for the increased epidermal keratinocytes migration immediately after skin injury. The results of this work could be useful for the development of new therapeutic approaches for improvement of skin wound healing.