Basal cell carcinoma: cell of origin, cancer stem cell hypothesis and stem cell markers

Natural Compounds in Non-Melanoma Skin Cancer: Prevention and Treatment

The elevated occurrence of non-melanoma skin cancer (NMSC) and the adverse effects associated with available treatments adversely impact the quality of life in multiple dimensions. In connection with this, there is a necessity for alternative approaches characterized by increased tolerance and lower side effects. Natural compounds could be employed due to their safety profile and effectiveness for inflammatory and neoplastic skin diseases. These anti-cancer drugs are often derived from natural sources such as marine, zoonotic, and botanical origins. Natural compounds should exhibit anti-carcinogenic actions through various pathways, influencing apoptosis potentiation, cell proliferation inhibition, and metastasis suppression. This review provides an overview of natural compounds used in cancer chemotherapies, chemoprevention, and promotion of skin regeneration, including polyphenolic compounds, flavonoids, vitamins, alkaloids, terpenoids, isothiocyanates, cannabinoids, carotenoids, and ceramides.

A Comparative Study of CD56 and Smooth Muscle Actin Expression in Basal and Squamous Cell Carcinomas

ABSTRACT

Basal cell carcinoma (BCC) and squamous cell carcinoma (SCC) are the 2 most common types of nonmelanoma skin tumors. Clinical or histopathological diagnostic challenges are encountered on occasion. CD56 and smooth muscle actin (SMA) are highly expressed in BCCs. We aimed to investigate the frequency of these markers, along with B-cell lymphoma 2 (Bcl-2) and Ki67. This study was conducted to propose a method that could possibly be of diagnostic value. One hundred twenty-eight BCC and 39 SCC cases were included in this study. CD56, SMA, Bcl-2, and Ki67 immunohistochemical stains were applied. Ninety-nine (77.3%) BCC and 6 (15.4%) SCC cases showed CD56 immunoreactivity. SMA expression was detected in 78.1% of BCC and 5.1% of SCC cases. CD56, SMA, and Bcl-2 expressions were significantly higher in BCC cases. The Ki67 proliferation index was found significantly higher in SCC cases. When basosquamous carcinoma cases were compared with SCC cases, a significant correlation between tumors and expression of CD56, SMA, and Bcl-2 were obtained. CD56 and SMA, in addition to Bcl-2, favor BCC. Ki67 should also be included in the panel to demonstrate the proliferative activity.

Exploring the promising potential of induced pluripotent stem cells in cancer research and therapy

The advent of iPSCs has brought about a significant transformation in stem cell research, opening up promising avenues for advancing cancer treatment. The formation of cancer is a multifaceted process influenced by genetic, epigenetic, and environmental factors. iPSCs offer a distinctive platform for investigating the origin of cancer, paving the way for novel approaches to cancer treatment, drug testing, and tailored medical interventions. This review article will provide an overview of the science behind iPSCs, the current limitations and challenges in iPSC-based cancer therapy, the ethical and social implications, and the comparative analysis with other stem cell types for cancer treatment. The article will also discuss the applications of iPSCs in tumorigenesis, the future of iPSCs in tumorigenesis research, and highlight successful case studies utilizing iPSCs in tumorigenesis research. The conclusion will summarize the advancements made in iPSC-based tumorigenesis research and the importance of continued investment in iPSC research to unlock the full potential of these cells.

Basal cell carcinoma of the umbilicus associated with sweat gland structures: Two case reports

RATIONALE

Basal cell carcinoma (BCC) arising in the umbilicus is relatively rare, and in particular, there have been few reports mentioning peritumoral sweat gland structures histopathologically. We herein, report 2 cases of umbilical BCC with sweat gland structures within and around the tumor.

PATIENT CONCERNS

A 61-year-old woman had a 2-year history of black exudative plaque in her umbilicus, and an 80-year-old woman had a 6-month history of dark brownish plaque in the umbilicus, with exudation 2 months prior to her first visit.

DIAGNOSES

Based on the histopathological finding, both cases were confirmed as BCC. The results of immunohistochemical staining showed that the tumor cells were Ber-EP4 positive. In addition, EMA-positive glandular structures were seen within and around the tumor.

INTERVENTIONS

Curative resection at the level of the linea alba on the bottom side was performed.

OUTCOMES

No relapse has been observed since resection in either patient.

LESSONS

We herein report 2 cases of umbilical BCC with sweat glands and ducts. Although whether peri- and/or intra-tumor sweat gland structures are the source of the tumor or arise by transdifferentiation from tumor cells remains unclear, these findings may provide clues to help understand the morphopathogenesis of umbilical BCC in the future.

CD56 and smooth muscle actin immunoreactivity in basal cell carcinomas: Are they indicators of differentiation or do they hold a diagnostic use?

BACKGROUND

Basal cell carcinoma (BCC) is the most common cutaneous malignancy and may show various differentiations. The possible pluripotent stem cell lineage of BCCs, whose origins are controversial today, is thought to be the main reason for the different morphologies. The aim of the study is to evaluate the expression of some neuroendocrine and smooth muscle markers of differentiation in BCCs and investigate the relationship between histopathologic subtypes and recurrence.

METHODS

A total of 128 cases diagnosed as BCC in our center were included. Immunohistochemical studies of CD56, synaptophysin, chromogranin-A, smooth muscle actin (SMA), desmin, caldesmon, and Ki67 were applied.

RESULTS

CD56, chromogranin-A, and synaptophysin immunoreactivity were detected in 77.3%, 13.3%, and 0.8% of the cases, respectively. 78.1% showed SMA positivity while no tumor expressed desmin or caldesmon. A correlation between histopathologic recurrence risk groups and CD56 expression was found (p < 0.05).

CONCLUSIONS

CD56 and SMA immunoreactivity is present in the majority of BCCs. However, the available findings do not support neuroendocrine or smooth muscle differentiation. CD56 antigen can be used for prognostic purposes in detecting high recurrence risk tumors. After the investigation of the expression rates of these two antigens in different cutaneous tumors, it may be appropriate to use them for diagnostic purposes in BCCs.

Photoacoustic imaging of periorbital skin cancer ex vivo: unique spectral signatures of malignant melanoma, basal, and squamous cell carcinoma

Radical excision of periorbital skin tumors is difficult without sacrificing excessive healthy tissue. Photoacoustic (PA) imaging is an emerging non-invasive biomedical imagi--ng modality that has potential for intraoperative micrographic control of surgical margins. This is the first study to assess the feasibility of PA imaging for the detection of periocular skin cancer. Eleven patients underwent surgical excision of periocular skin cancer, one of which was a malignant melanoma (MM), eight were basal cell carcinomas (BCCs), and two squamous cell carcinomas (SCCs). Six tumors were located in the eyelid, and five in periocular skin. The excised samples, as well as healthy eyelid samples, were scanned with PA imaging postoperatively, using 59 wavelengths in the range 680-970 nm, to generate 3D multispectral images. Spectral unmixing was performed using endmember spectra for oxygenated and deoxygenated Hb, melanin, and collagen, to iden--tify the chromophore composition of tumors and healthy eyelid tissue. After PA scanning, the tumor samples were examined histopathologically using standard hematoxylin and eosin staining. The PA spectra of healthy eyelid tissue were dominated by melanin in the skin, oxygenated and deoxygenated hemoglobin in the orbicularis oculi muscle, and collagen in the tarsal plate. Multiwavelength 3D scanning provided spectral information on the three tumor types. The spectrum from the MM was primarily reconstructed by the endmember melanin, while the SCCs showed contributions primarily from melanin, but also HbR and collagen. BCCs showed contributions from all four endmembers with a predominance of HbO₂ and HbR. PA imaging may be used to distinguish different kinds of periocular skin tumors, paving the way for future intraoperative micrographic control.

Aspects of the Tumor Microenvironment Involved in Immune Resistance and Drug Resistance

The tumor microenvironment (TME) is a complex and ever-changing "rogue organ" composed of its own blood supply, lymphatic and nervous systems, stroma, immune cells and extracellular matrix (ECM). These complex components, utilizing both benign and malignant cells, nurture the harsh, immunosuppressive and nutrient-deficient environment necessary for tumor cell growth, proliferation and phenotypic flexibility and variation. An important aspect of the TME is cellular crosstalk and cell-to-ECM communication. This interaction induces the release of soluble factors responsible for immune evasion and ECM remodeling, which further contribute to therapy resistance. Other aspects are the presence of exosomes contributed by both malignant and benign cells, circulating deregulated microRNAs and TME-specific metabolic patterns which further potentiate the progression and/or resistance to therapy. In addition to biochemical signaling, specific TME characteristics such as the hypoxic environment, metabolic derangements, and abnormal mechanical forces have been implicated in the development of treatment resistance. In this review, we will provide an overview of tumor microenvironmental composition, structure, and features that influence immune suppression and contribute to treatment resistance.

Pathogenesis of Keratinocyte Carcinomas and the Therapeutic Potential of Medicinal Plants and Phytochemicals

Keratinocyte carcinoma (KC) is a form of skin cancer that develops in keratinocytes, which are the predominant cells present in the epidermis layer of the skin. Keratinocyte carcinoma comprises two sub-types, namely basal cell carcinoma (BCC) and squamous cell carcinoma (SCC). This review provides a holistic literature assessment of the origin, diagnosis methods, contributing factors, and current topical treatments of KC. Additionally, it explores the increase in KC cases that occurred globally over the past ten years. One of the principal concepts highlighted in this article is the adverse effects linked to conventional treatment methods of KC and how novel treatment strategies that combine phytochemistry and transdermal drug delivery systems offer an alternative approach for treatment. However, more in vitro and in vivo studies are required to fully assess the efficacy, mechanism of action, and safety profile of these phytochemical based transdermal chemotherapeutics.

Eyelid skin trichilemmoma and underlying local malignancy: is an aggressive treatment necessary?

Objective

Trichilemmoma is a benign tumour derived from the outer root sheath of hair follicles. Trichilemmoma can be associated with basal cell carcinoma (BCC), either as a collision lesion or from malignant transformation. This study evaluates malignancy associated with eyelid trichilemmoma and principles of treatment.

Methods and analysis

Retrospective study involving biopsy-proven eyelid trichilemmoma cases over 14 years encountered at a tertiary referral centre. Presenting features, differential diagnosis, type and number of operations required and histopathological features including coexisting BCC were analysed.

Results

We identified 36 cases with an average age of 66 years. The clinical differential diagnoses were mainly BCC (44%), papilloma (36%) and squamous cell carcinoma (SCC) (3%). Three patients (8%) had trichilemmoma with associated BCC. Of the 19 cases (53%) of trichilemmomas without BCC with equivocal surgical margins, seven patients (19%) opted for further excision while 12 patients (33%) opted for observation and were discharged. A patient re-presented two years later with invasive BCC. Overall, 11% of our biopsy-proven eyelid trichilemmoma cases were associated with BCC.

Conclusion

Patients should be informed that a proportion of incompletely excised eyelid trichilemmomas may conceal underlying BCC. Therefore, further surgery to achieve clear surgical margins should be offered. Patients who opt for observation should be offered 6-monthly follow-up for three to five years. Alternatively, they can be discharged with advice to report any recurrence of lumps, skin changes or loss of lashes at the site of previous lesion.

Photoacoustic imaging for three-dimensional visualization and delineation of basal cell carcinoma in patients

BACKGROUND

Photoacoustic (PA) imaging is an emerging non-invasive biomedical imaging modality that could potentially be used to determine the borders of basal cell carcinomas (BCC) preoperatively in order to reduce the need for repeated surgery.

METHODS

Two- and three-dimensional PA images were obtained by scanning BCCs using 59 wavelengths in the range 680-970 nm. Spectral unmixing was performed to visualize the tumor tissue distribution. Spectral signatures from 38 BCCs and healthy tissue were compared ex vivo.

RESULTS AND DISCUSSION

The PA spectra could be used to differentiate between BCC and healthy tissue ex vivo (p < 0.05). Spectral unmixing provided visualization of the overall architecture of the lesion and its border.

CONCLUSION

PA imaging can be used to differentiate between BCC and healthy tissue and can potentially be used to delineate tumors prior to surgical excision.

Unique spectral signature of human cutaneous squamous cell carcinoma by photoacoustic imaging

Cutaneous squamous cell carcinoma (cSCC) is a common skin cancer with metastatic potential. To reduce reoperations due to nonradical excision, there is a need to develop a technique for identification of tumor margins preoperatively. Photoacoustic (PA) imaging is a novel imaging technology that combines the strengths of laser optics and ultrasound. Our aim was to determine the spectral signature of cSCC using PA imaging and to use this signature to visualize tumor architecture and borders. Two-dimensional PA images of 33 cSCCs and surrounding healthy skin were acquired ex vivo, using 59 excitation wavelengths from 680 to 970 nm. The spectral response of the cSCCs was compared to healthy tissue, and the difference was found to be greatest at wavelengths in the range 765 to 960 nm (P < .05). Three-dimensional PA images were constructed from spectra obtained in the y-z plane using a linear stepper motor moving along the x-plane. Spectral unmixing was then performed which provided a clear three-dimensional view of the distribution of tumor masses and their borders.

Stem Cells as a Target for the Delivery of Active Molecules to Skin by Topical Administration

Cutaneous stem cells, gained great attention in the field of regenerative medicine as a potential therapeutic target for the treatment of skin and hair disorders and various types of skin cancers. Cutaneous stem cells play a key role in several processes like the renovation of skin structures in the condition of homeostasis and after injuries, the hair follicle growth and the reconstruction and production of melanocytes. Thus, gaining effective access to skin stem cells for therapeutic interventions that often involve active molecules with non-favorable characteristics for skin absorption is a valuable achievement. The topical route with high patient compliance and several other benefits is gaining increasing importance in basic and applied research. However, the major obstacle for topical drug delivery is the effective barrier provided by skin against penetration of the vast majority of exogenous molecules. The research in this field is focusing more and more on new strategies to circumvent and pass this barrier effectively. In this article the existing approaches are discussed considering physical and chemical methods along with utilization of novel drug delivery systems to enhance penetration of drugs to the skin. In particular, attention has been paid to studies finalized to the delivery of molecules to cutaneous stem cells with the aim of transferring signals, modulating their metabolic program, inducing physiological modifications and stem cell gene therapy.

DZIP1 Promotes Proliferation, Migration, and Invasion of Oral Squamous Carcinoma Through the GLI1/3 Pathway

BACKGROUND

DZIP1 is an oncogene involved in the progression and stemness of carcinoma through the Wnt/β-catenin pathway, and the potential mechanism of DZIP1 in oral squamous cancer remains unknown. The aim of this study was to uncover the effect and mechanism of DZIP1 in the progression of oral squamous carcinoma.

METHODS

TCGA database scanning was applied to verify dysregulated genes in oral squamous carcinoma. quantitative real-time polymerase chain reaction, immunohistochemistry, and Western blotting assays were used to detect the expression of DZIP1 in tissues and cell lines. We established stable DZIP1-overexpressing and DZIP1 knockdown cell lines. We investigated the biological function and the underlying mechanism of DZIP1 through a series of experiments.

RESULTS

DZIP1 was one of the genes discovered by the scanning strategy to be upregulated in cancer tissue and negatively correlated with the overall survival (OS) of patients. DZIP1 promotes proliferation, migration, and invasion in an oral squamous carcinoma cell line through EMT in a GLI1/3-dependent manner.

CONCLUSIONS

DZIP1 promotes the proliferation, migration, and invasion of oral squamous carcinoma through the GLI1/3 pathway.

The role of SOX family members in solid tumours and metastasis

Cancer is a heavy burden for humans across the world with high morbidity and mortality. Transcription factors including sex determining region Y (SRY)-related high-mobility group (HMG) box (SOX) proteins are thought to be involved in the regulation of specific biological processes. The deregulation of gene expression programs can lead to cancer development. Here, we review the role of the SOX family in breast cancer, prostate cancer, renal cell carcinoma, thyroid cancer, brain tumours, gastrointestinal and lung tumours as well as the entailing therapeutic implications. The SOX family consists of more than 20 members that mediate DNA binding by the HMG domain and have regulatory functions in development, cell-fate decision, and differentiation. SOX2, SOX4, SOX5, SOX8, SOX9, and SOX18 are up-regulated in different cancer types and have been found to be associated with poor prognosis, while the up-regulation of SOX11 and SOX30 appears to be favourable for the outcome in other cancer types. SOX2, SOX4, SOX5 and other SOX members are involved in tumorigenesis, e.g. SOX2 is markedly up-regulated in chemotherapy resistant cells. The SoxF family (SOX7, SOX17, SOX18) plays an important role in angio- and lymphangiogenesis, with SOX18 seemingly being an attractive target for anti-angiogenic therapy and the treatment of metastatic disease in cancer. In summary, SOX transcription factors play an important role in cancer progression, including tumorigenesis, changes in the tumour microenvironment, and metastasis. Certain SOX proteins are potential molecular markers for cancer prognosis and putative potential therapeutic targets, but further investigations are required to understand their physiological functions.

Current concepts and challenges to unravel the role of iodothyronine deiodinases in human neoplasias

Thyroid hormones (THs) are essential for the regulation of several metabolic processes and the energy consumption of the organism. Their action is exerted primarily through interaction with nuclear receptors controlling the transcription of thyroid hormone-responsive genes. Proper regulation of TH levels in different tissues is extremely important for the equilibrium between normal cellular proliferation and differentiation. The iodothyronine deiodinases types 1, 2 and 3 are key enzymes that perform activation and inactivation of THs, thus controlling TH homeostasis in a cell-specific manner. As THs seem to exert their effects in all hallmarks of the neoplastic process, dysregulation of deiodinases in the tumoral context can be critical to the neoplastic development. Here, we aim at reviewing the deiodinases expression in different neoplasias and exploit the mechanisms by which they play an essential role in human carcinogenesis. TH modulation by deiodinases and other classical pathways may represent important targets with the potential to oppose the neoplastic process.

Basal Cell Carcinoma Arises from Interfollicular Layer of Epidermis

Background

BCC is currently the most common type of skin cancer in humans. Although having a low-grade malignancy and metastatic potential, BCC is locally aggressive and destructive. Despite numerous studies, the origin of BCC, whether arising from the follicular or interfollicular layer, remains controversial.

Objectives

This study aims to evaluate whether BCC arises from the follicular or interfollicular layer by using immunohistochemical staining.

Methods

Twenty-three specimens of superficial and nodular BCC at its very early stage were examined. The samples were immunohistochemically stained using BerEP4 antibody. The stained specimens were then examined and scored by 2 independent observers.

Results

BerEP4 was found to be strongly positive in all BCC lesions, including a very early lesions budding off the basal layer of the epidermis.

Conclusion

This study confirmed that the origin site of BCC is basal layer of epidermis. This finding suggests that BCC arises from the interfollicular epidermis.

Cytokeratin Profile of Basal Cell Carcinomas According to the Degree of Sun Exposure and to the Anatomical Localization

Basal cell carcinoma (BCC) seems to originate from ultraviolet light-induced mutations involving the bulge or the outer sheath of the hair follicle cells. However, the etiopathogenic mechanisms involved in the development of these tumors in nonphotoexposed and in hairless areas remain unclear. The cytokeratin (CK) profile (including CK5/6, CK7, CK14, CK15, CK17, and CK19) from a series of different BCC subtypes developing in sun-exposed and non-sun-exposed areas, including hairless regions, was evaluated. The authors have observed that CK7 expression in BCC is associated with the anatomical localization of the tumor and its sun-exposition, but not with other factors such as histological subtype. The expression of this CK is higher in BCCs located in non-sun-exposed and nonhairy areas, such as the vulvar semimucosa and the nipple. Because CK7 is a marker of simple glandular epithelia, the authors suggest a glandular origin for BCCs located in hairless and nonphotoexposed areas.

From basal cell carcinoma morphogenesis to the alopecia induced by hedgehog inhibitors: connecting the dots

The deciphering of the hedgehog (Hh) signalling pathway implicated in the tumorigenesis of basal cell carcinoma (BCC) led to the development of targeted drug therapies, the Hh pathway inhibitors (HPIs) vismodegib and sonidegib. In the skin, physiological Hh signalling is activated in growing hair follicles (HFs), where it is required for proliferation of the epithelium of HFs during morphogenesis and for their postnatal growth. The effects of HPI treatment leading to the regression of BCC and the development of alopecia underpin the central role of the Hh pathway in BCC formation, as well as hair cycling. Given the fact that BCC is a follicular-driven tumour, it is a fine tuning of events that regulate hair cycling that may drive towards the formation of benign follicular hamartomas or malignant BCC neoplasms. Wnt/β-catenin signalling interacts with the Hh signalling during HF morphogenesis, normal hair cycling and BCC development. The aim of this review is to present how key molecular events implicated in Hh pathway crosstalk in the HF are also involved in BCC pathogenesis and result in the alopecia developed by HPI treatment.

p40 in Conjunction With CK20 and E-Cadherin Distinguishes Primary Adnexal Neoplasms of the Skin

Although basal cell carcinomas (BCC) show typical histomorphologic features, they sometimes remain difficult in distinction from benign adnexal skin tumors of follicular origin like trichoepithelioma (TE) or trichoblastoma (TB). Consequently, an immunohistochemical marker panel separating described entities would be helpful in clinical routine. Thus, we stained 22 skin lesions (BCC, TE, and TB) against β-catenin, CK20, E-cadherin, p40, and p63. The staining pattern was described and quantified using an immunohistochemical score. Although p40 and p63 revealed a strong staining intensity of all skin lesions without distinction between BCC and benign lesions (P=1.000), established Merkel cell marker CK20 illustrated a loss of staining in BCC compared with TE and TB (P=0.007). In contrast, BCC exhibited an increased expression of E-cadherin in relation to TE and TB (P=0.009). Single application of CK20 or E-cadherin could predict diagnosis of BCC in 81.8% or 72.7%, respectively. Combining consecutive staining of E-cadherin and CK20 could even enhance specificity toward diagnosis of TE or TB. Hence, findings of our study imply that sequential staining of CK20 and E-cadherin prevents false-positive classification of BCC. Furthermore, our study demonstrated that p40 exhibits the same staining pattern in BCC, TE, and TB. Therefore, p40 might replace p63 equivalently establishing diagnosis of primary adnexal neoplasms of the skin in the form of BCC as well as benign adnexal tumors. As a result, the depicted immunohistochemical marker panel may be applied for adnexal skin neoplasms as a diagnostic adjunct especially in surgically challenging body regions.

Epigenetics in cancer stem cells

Compelling evidence have demonstrated that bulk tumors can arise from a unique subset of cells commonly termed "cancer stem cells" that has been proposed to be a strong driving force of tumorigenesis and a key mechanism of therapeutic resistance. Recent advances in epigenomics have illuminated key mechanisms by which epigenetic regulation contribute to cancer progression. In this review, we present a discussion of how deregulation of various epigenetic pathways can contribute to cancer initiation and tumorigenesis, particularly with respect to maintenance and survival of cancer stem cells. This information, together with several promising clinical and preclinical trials of epigenetic modulating drugs, offer new possibilities for targeting cancer stem cells as well as improving cancer therapy overall.

Implication of downregulation and prospective pathway signaling of microRNA-375 in lung squamous cell carcinoma

BACKGROUND

Lung cancer is one of the most typical cancers in the world. Altered expression profiles of microRNA-375(miR-375) are linked to many diseases including lung cancer. However, the relationship between miR-375 and lung squamous cell carcinoma (LUSC) is controversial.

METHODS

We first evaluated the 23 LUSCs and the paired normal lung tissues by qRT-PCR. Then we analyzed the LUSC samples with miR-375 expression based on The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO). Furthermore, bioinformatics analysis was performed to explore the biological role of miR-375 in LUSC.

RESULTS

The expression of miR-375 was remarkably reduced in LUSC tissues compared with that in paired lung tissues by qRT-PCR (P=0.003). Additionally, the TCGA dataset suggested that miR-375 was significantly downregulated in 478 LUSC tissues compared with 45 normal lung tissues (P<0.0001), as well as the result derived from GEO datasets (the pooled SMD=-1.01; 95%CIs-1.66 to -0.33, P=0.004). Furthermore, a total of 1348 miR-375-related differently expressed genes were identified by the analytical integration, which were involved in critical pathways of LUSC like neuron differentiation, plasma membrane part and sequence-specific DNA binding. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway examination also unveiled the involvement of target genes in morphine addiction and drug metabolism- other enzymes and neuroactive ligand-receptor interaction. Finally, the expression of WNT5A was inversely correlated with miR-375 expression according to TCGA dataset (r=-0.2342, P<0.0001).

CONCLUSIONS

miR-375 exerts a strong tumor-suppressive effect in LUSC and provided novel insight into the biological function in tumorigenesis and progression of LUSC.

Immunohistochemical expression of cytokeratin 15, cytokeratin 19, follistatin, and Bmi-1 in basal cell carcinoma

BACKGROUNDS

Basal cell carcinoma (BCC) is the most common cutaneous neoplasm. Despite numerous previous studies, the origin of BCC is still controversial.

OBJECTIVE

The aim of this study is to evaluate whether BCC arises from the hair follicle rather than the epidermal basal cell.

METHODS

The labeling index and differences of expression of the immunohistochemical (IHC) stainings of CK15, CK19, follistatin, and Bmi-1 were evaluated in 20 cases of BCC, 13 cases of trichoblastoma, 21 cases of actinic keratosis (AK), and 19 cases of squamous cell carcinoma (SCC) which were biopsied in the department of dermatology of the Yeungnam University Medical Center.

RESULTS

For CK15, labeling indexes of BCC (83.0%) and trichoblastoma (84.4%) were significantly higher than those of AK (15.9%) and SCC (15.8%). For CK19, labeling indexes of BCC (8.1%), trichoblastoma (6.6%), AK (3.5%), and SCC (14.8%) revealed no difference. For follistatin, labeling indexes of BCC (51.1%) and trichoblastoma (70.1%) were significantly higher than those of AK (0.9%) and SCC (8.5%). For Bmi-1, labeling indexes of BCC (74.4%) and trichoblastoma (84.7%) were significantly higher than those of AK (24.7%) and SCC (18.6%).

CONCLUSION

In this study, strong positivity of CK15, follistatin, and Bmi-1 was more frequently observed in BCC and trichoblastoma than in SCC and AK. These findings suggest that BCC and trichoblastoma share the same differentiation toward the hair follicle. Furthermore, CK15, follistatin, and Bmi-1 can be useful as markers to differentiate BCC from SCC.

From Normal Skin to Squamous Cell Carcinoma: A Quest for Novel Biomarkers

Squamous cells carcinoma (SCC) is the second most frequent of the keratinocyte-derived malignancies after basal cell carcinoma and is associated with a significant psychosocial and economic burden for both the patient himself and society. Reported risk factors for the malignant transformation of keratinocytes and development of SCC include ultraviolet light exposure, followed by chronic scarring and inflammation, exposure to chemical compounds (arsenic, insecticides, and pesticides), and immune-suppression. Despite various available treatment methods and recent advances in noninvasive or minimal invasive diagnostic techniques, the risk recurrence and metastasis are far from being negligible, even in patients with negative histological margins and lymph nodes. Analyzing normal, dysplastic, and malignant keratinocyte proteome holds special promise for novel biomarker discovery in SCC that could be used in the future for early detection, risk assessment, tumor monitoring, and development of targeted therapeutic strategies.

Expression of epidermal stem cell markers in skin and adnexal malignancies

BACKGROUND

Epidermal stem cells are multipotent cells that maintain the skin epidermis. Potential markers for stem cells have been identified in mammalian skin from mouse experiments; however, it is unclear if stem cells also contribute to tumour formation in human skin.

OBJECTIVES

To investigate the expression of potential stem cell markers, such as leucine-rich repeat-containing G protein-coupled receptor (Lgr) 5, Lgr6, leucine-rich repeats and immunoglobulin-like domain protein 1 (Lrig1) and cytokeratin 15 (CK15) in basal cell carcinomas and tumours of the skin appendages.

METHODS

We tested 45 human basal cell carcinomas (BCCs), including superficial, nodular, adenoid, infiltrating and sclerosing types, and 38 human tumours of skin appendages, including 13 sebaceous adenomas and carcinomas, 20 eccrine sweat gland tumours and five pilomatricomas, for the expression of hair follicle stem cell markers such as Lgr5, Lrig1, CK15, β-catenin and SRY (sex determining region Y)-box 9 (SOX9), and compared these findings with those of healthy age-matched human epidermis.

RESULTS

We detected the expression of stem cell markers in all tumours tested. Regarding Lgr5, Lrig1, CK15 and SOX9, expression seemed to be lower in more aggressive tumour types, such as in the most advanced parts of infiltrating BCC, in sebaceous carcinoma and late-stage porocarcinoma, compared with less aggressive superficial or nodular BCC or early-stage porocarcinoma and sebaceous gland tumours. In aggressive, sclerosing BCC, Lrig1 and Lgr5 were downregulated but CK15, SOX9 and nuclear β-catenin were upregulated.

CONCLUSIONS

Expression of potential stem cell markers of the epidermis and hair follicles was observed in skin tumours of appendages and BCCs. However, during tumour progression, many of these markers seemed to be downregulated.

In vivo assessment of optical properties of basal cell carcinoma and differentiation of BCC subtypes by high-definition optical coherence tomography

High-definition optical coherence tomography (HD-OCT) features of basal cell carcinoma (BCC) have recently been defined. We assessed in vivo optical properties (IV-OP) of BCC, by HD-OCT. Moreover their critical values for BCC subtype differentiation were determined. The technique of semi-log plot whereby an exponential function becomes linear has been implemented on HD-OCT signals. The relative attenuation factor (µraf ) at different skin layers could be assessed.. IV-OP of superficial BCC with high diagnostic accuracy (DA) and high negative predictive values (NPV) were (i) decreased µraf in lower part of epidermis and (ii) increased epidermal thickness (E-T). IV-OP of nodular BCC with good to high DA and NPV were (i) less negative µraf in papillary dermis compared to normal adjacent skin and (ii) significantly decreased E-T and papillary dermal thickness (PD-T). In infiltrative BCC (i) high µraf in reticular dermis compared to normal adjacent skin and (ii) presence of peaks and falls in reticular dermis had good DA and high NPV. HD-OCT seems to enable the combination of in vivo morphological analysis of cellular and 3-D micro-architectural structures with IV-OP analysis of BCC. This permits BCC sub-differentiation with higher accuracy than in vivo HD-OCT analysis of morphology alone.

Potential Biomarkers in Diagnosis of Human Gastric Cancer

The high incidence of gastric cancer (GC) and its consequent mortality rate severely threaten human's health. It is not frequently diagnosed until a relatively advanced stage. Surgery is the only potentially curative treatment. Thus, early screening and diagnosis are critical for patients with GC. The tumor marker assays used currently for detecting GC are simple and rapid, but the usage is limited by its low sensitivity and specificity. Here, we provide a brief description of some new potential markers and new biotechnological methods for the diagnosis of GC, hoping to find out more effective approaches for early detection of GC.

Side population cells separated from A549 lung cancer cell line possess cancer stem cell-like properties and inhibition of autophagy potentiates the cytotoxic effect of cisplatin

Recent studies have suggested that cancer stem cells (CSCs) may be responsible for tumorigenesis and contribute to resistance to chemotherapy. Side population (SP) cells are thought to be enriched for CSCs in most types of human tumors. Therefore, the aim of the present study was to sort SP cells using an A549 lung cancer cell line, identify the cancer stem cell-like properties of SP and determine the role of autophagy in the survival of SP cells of lung cancer. SP cells were isolated by fluorescence-activated cell sorter (FACS) from A549 lung cancer cells, and the CSC-like properties were verified through confocal fluorescence imaging, sphere formation assays, cell proliferation and colony formation assay, gene expression in vitro and tumor formation in vivo. The role of autophagy in the survival of SP cells was assessed by western blotting and flow cytometric analysis. A549 lung cancer cells contained 1.10% SP cells. SP cells showed higher abilities of sphere and colony formation, cell proliferation and self-renewal. Moreover, compared to non-SP, SP cells demonstrated a higher mRNA expression of stem cell markers (MDR1, ABCG2 and OCT-4). The clone formation efficiency of SP cells was significantly higher than that non-SP cells under the same conditions. Expression of autophagosomes in SP cells was markedly lower than that in non-SP cells. However, the level of autophagy in SP cells was found to be markedly increased in the presence of cisplatin. In addition, inhibition of autophagy enhanced the effects of apoptosis induced by cisplatin. SP cells from the A549 lung cancer cell line possessed the properties of CSCs and were used to investigate the further characteristics of lung CSCs. SP cells were more resistant to chemotherapy and inhibition of autophagy enhanced the effects of apoptosis induced by the chemotherapeutic agent, cisplatin. These results may provide insight into novel therapeutic targets.

Trichilemmoma in continuity with pigmented basal cell carcinoma; with dermatoscopy and dermatopathology

A case of trichilemmoma in continuity with a pigmented basal cell carcinoma is presented with dermatoscopy and dermatopathology. The distinction between the two lesions was evident dermatoscopically and was confirmed dermatopathologically. While trichilemmoma has been reported in association with basal cell carcinoma and dermatoscopy images of four previous cases of trichilemmoma have been published, no previous dermatoscopy image has been published of trichilemmoma associated with basal cell carcinoma.

Sonic hedgehog signaling in Basal cell nevus syndrome

The hedgehog (Hh) signaling pathway is considered to be a major signal transduction pathway during embryonic development, but it usually shuts down after birth. Aberrant Sonic hedgehog (Shh) activation during adulthood leads to neoplastic growth. Basal cell carcinoma (BCC) of the skin is driven by this pathway. Here, we summarize information related to the pathogenesis of this neoplasm, discuss pathways that crosstalk with Shh signaling, and the importance of the primary cilium in this neoplastic process. The identification of the basic/translational components of Shh signaling has led to the discovery of potential mechanism-driven druggable targets and subsequent clinical trials have confirmed their remarkable efficacy in treating BCCs, particularly in patients with nevoid BCC syndrome (NBCCS), an autosomal dominant disorder in which patients inherit a germline mutation in the tumor-suppressor gene Patched (Ptch). Patients with NBCCS develop dozens to hundreds of BCCs due to derepression of the downstream G-protein-coupled receptor Smoothened (SMO). Ptch mutations permit transposition of SMO to the primary cilium followed by enhanced expression of transcription factors Glis that drive cell proliferation and tumor growth. Clinical trials with the SMO inhibitor, vismodegib, showed remarkable efficacy in patients with NBCCS, which finally led to its FDA approval in 2012.

The changes in the expression levels of follicular markers in keratoacanthoma depend on the stage: keratoacanthoma is a follicular neoplasm exhibiting infundibular/isthmic differentiation without expression of CK15

BACKGROUND

Although the precise etiology of keratoacanthoma (KA) is unknown, KA is generally assumed to differentiate toward hair follicles based on previous studies of experimental carcinogenesis.

METHODS

We performed a comprehensive immunohistochemical study of various follicular markers in all stages of KA. A total of 67 tumors, including 16 early or proliferative stage lesions, 43 well-developed stage lesions, five regressing stage lesions and three regressed stage lesions, were subjected to the analysis.

RESULTS

CK15 (clone C8/144B), CK19 and CD34 were not expressed at any stage. CK1, CK10, CK16, CK17, CK15 (clone LHK15) and calretinin showed dynamic changes in their expression in KA depending on the stage.

CONCLUSIONS

KA is a follicular neoplasm with infundibular/isthmic (upper segmental region of hair follicles) differentiation. It is considered that early or proliferative stage tumors show keratin-filled invaginations with infundibular differentiation and gradual isthmic differentiation. Well-developed examples of KA generally show isthmic differentiation in the whole lesions. The regressed stage KAs lose the features of this type of follicular differentiation and show epidermal characteristics. No expression of CK15 (clone C8/144B) was observed in KAs, although this finding is insufficient to completely rule out the correlation between the regression of KA and the hair follicle cycle.

Downregulation of PAX6 by shRNA inhibits proliferation and cell cycle progression of human non-small cell lung cancer cell lines

Background

The transcription factor PAX6 is primarily expressed in embryos. PAX6 is also expressed in several tumors and plays an oncogenic role. However, little is known about the role of PAX6 in lung cancer.

Methods

The function of PAX6 in lung cancer cells was evaluated by small interfering RNA-mediated depletion of the protein followed by analyses of cell proliferation, anchorage-independent growth, and cell cycle arrest. The changes of cyclin D1, pRB, ERK1/2, p38 expression caused by PAX6 inhibition were detected using western-blotting. The PAX6 mRNA level in 52 pairs of tumors and corresponding matched adjacent normal tissues from non-small cell lung cancer patients and lung cancer cell lines was detected by real-time PCR.

Results

Suppression of PAX6 expression inhibited cell growth and colony formation in A549 and H1299 cells. The percentage of cells in G1-phase increased when PAX6 expression was inhibited. The cyclin D1 protein level, as well as the pRB phosphorylation level, decreased as a result of PAX6 down-regulation. The activity of ERK1/2 and p38 was also suppressed in PAX6 knock-down cells. The PAX6 mRNA was highly expressed in lung cancer tissue and lung cancer cell lines. In most patients (about 65%), the relative ratio of PAX6 mRNA in primary NSCLC versus adjacent tissues exceeded 100.

Conclusions

Our data implicated that PAX6 accelerates cell cycle progression by activating MAPK signal pathway. PAX6 mRNA levels were significantly elevated in primary lung cancer tissues compared to their matched adjacent tissues.

Cerebral angiogenesis during development: who is conducting the orchestra?

Blood vessels provide the brain with the oxygen and the nutrients it requires to develop and function. Endothelial cells (ECs) are the principal cell type forming the vascular system and driving its development and remodeling. All vessels are lined by a single EC layer. Larger blood vessels are additionally enveloped by vascular smooth muscle cells (VSMCs) and pericytes, which increase their stability and regulate their perfusion and form the blood-brain barrier (BBB). The development of the vascular system occurs by two processes: (1) vasculogenesis, the de novo assembly of the first blood vessels, and (2) angiogenesis, the creation of new blood vessels from preexisting ones by sprouting from or by division of the original vessel. The walls of maturing vessels produce a basal lamina and recruit pericytes and vascular smooth muscle cells for structural support. Whereas the process of vasculogenesis seems to be genetically programmed, angiogenesis is induced mainly by hypoxia in development and disease. Both processes and the subsequent vessel maturation are further orchestrated by a complex interplay of inhibiting and stimulating growth factors and their respective receptors, many of which are hypoxia-inducible. This chapter intends to give an overview about the array of factors directing the development and maintenance of the brain vasculature and their interdependent actions.

CD133 expression in normal skin and in epithelial cutaneous tumors

Background. Expression of human CD133 (human prominin-1) in cancer cells has been postulated to be a marker of stemness and is considered as a putative marker of cancer stem cells (CSCs). We designed a study to describe the expression pattern of CD133 in normal skin and in epithelial cutaneous neoplasms. Methods. The CD133 immunohistochemical expression of forty-three eccrine and apocrine tumors was compared to that observed in other epithelial tumors of the skin. In addition, flow cytometry was used to detect the CD133 expression of four epithelial skin neoplasms, including one porocarcinoma. Results. CD133 immunoreactivity at the apical or at the apicolateral surface of cells forming glandular structures was observed. Cells from solid areas of benign or malignant tumors were not stained. The porocarcinoma derived culture cells showed a 22% of CD133 positive cells using flow cytometry, while squamous cell carcinoma cultures contained less than 0.1%. Conclusions. These observations indicate that CD133 is a specific marker of glandular differentiation that could be included in the diagnostic panel of cutaneous tumors with possible eccrine or apocrine differentiation. However, the use of CD133 expression as a marker of CSCs should be interpreted with caution in experiments of skin.

An ulcerated nodule on the nose

A 75-year-old retired nurse, originally from Barbados, presented to her general practitioner (GP) with a scaling ulcerated nodule on the left side of her nose. She was taking medication for type 2 diabetes, hypertension and glaucoma, but was otherwise well with no systemic symptoms. Her GP diagnosed a patch of eczema; however, a trial of topical steroids was not effective and she was referred to dermatology. A skin biopsy confirmed the clinical suspicion that this patient had a nodular basal cell carcinoma (BCC). BCCs account for 75% of all skin cancers; they very rarely metastasise, but can spread to invade local structures. Our patient has type VI skin. Skin cancer is rare in patients with skin type VI; however, in this group, morbidity and mortality are disproportionately high in relation to cancer incidence.

Imaging of basal cell carcinoma by high-definition optical coherence tomography: histomorphological correlation. A pilot study

BACKGROUND

With the continued development of noninvasive therapies for basal cell carcinoma (BCC) such as photodynamic therapy and immune therapies, noninvasive diagnosis and monitoring become increasingly relevant. High-definition optical coherence tomography (HD-OCT) is a high-resolution imaging tool, with micrometre resolution in both transversal and axial directions, enabling visualization of individual cells up to a depth of around 570 μm, and filling the imaging gap between conventional optical coherence tomography (OCT) and reflectance confocal microscopy (RCM).

OBJECTIVES

We sought to determine the feasibility of detecting BCC by this technique using criteria defined for RCM and conventional OCT and compared with histology.

METHODS

In this pilot study skin lesions of 21 patients with a histologically proven BCC were imaged by HD-OCT just before excision and images analysed qualitatively.

RESULTS

Features for four different BCC subtypes were described in both transverse and axial directions. In general, these features were subepidermal or intradermal aggregations of cells. These islands or trabeculae were surrounded by a less refractile border corresponding with palisading and peritumoral mucin production. There was a pronounced architectural disarray of the epidermis. A variably refractile stroma together with abundant dilated peritumoral blood vessels was present. These features were comparable with histological features for each patient.

CONCLUSIONS

Using features already suggested by RCM and conventional OCT, the study implies that HD-OCT facilitates in vivo diagnosis of BCC and allows the distinction between different BCC subtypes for increased clinical utility.

Hedgehog signaling pathway and its targets for treatment in basal cell carcinoma

Basal cell carcinoma (BCC) of the skin is the most common type of cancer and accounts for up to 40% of all cancers in the US, with a growing incidence rate over recent decades in all developed countries. Surgery is curative for most patients, although it leaves unaesthetic scars, but those that develop locally advanced or metastatic BCC require different therapeutic approaches. Furthermore, patients with BCC present a high risk of developing additional tumors. The increasing economic burden and the morbidity of BCC render primary interest in the development of targeted treatments for this disease. Among the molecular signals involved in the development of BCC, the critical role of the morphogenetic Hedgehog (Hh) pathway has become evident. This pathway is found altered and activated in almost all BCCs, both sporadic and inherited. Given the centrality of the Hh pathway in the pathophysiology of BCC, the primary efforts to identify molecular targets for the topical or systemic treatment of this cancer have focused on the Hh components. Several Hh inhibitors have been so far identified - from the first identified natural cyclopamine to the recently Food and Drug Administration-approved synthetic vismodegib - most of which target the Hh receptor Smoothened (either its function or its translocation to the primary cilium). Other molecules await further characterization (bisamide compounds), while drugs currently approved for other diseases such as itraconazole (an antimicotic agent) and vitamin D3 have been tested on BCC with encouraging results. The outcomes of the numerous ongoing clinical trials are expected to expand the field in the very near future. Further research is needed to obtain drugs targeting downstream components of the Hh pathway (eg, Gli) or to exploit combinatorial therapies (eg, with phosphatidylinositol 3-kinase inhibitors or retinoids) in order to overcome potential drug resistance.

Which are the cells of origin in merkel cell carcinoma?

Merkel cell carcinoma (MCC), a highly aggressive skin tumour with increasing incidence, is associated with the newly discovered Merkel cell polyomavirus (MCPyV). Studies on MCC and MCPyV as well as other risk factors have significantly increased our knowledge of MCC pathogenesis, but the cells of origin, which could be important targets in future therapies, are still unknown. Merkel cells (MCs), the neuroendocrine cells of the skin, were believed to be at the origin of MCC due to their phenotypic similarities. However, for several reasons, for example, heterogeneous differentiation of MCCs and postmitotic character of MCs, it is not very likely that MCC develops from differentiated MCs. Skin stem cells, probably from the epidermal lineage, are more likely to be cells of origin in MCC. Future studies will have to address these questions more directly in order to identify the physiological cells which are transformed to MCC cells.

Biochemistry of epidermal stem cells

BACKGROUND

The epidermis is an important protective barrier that is essential for maintenance of life. Maintaining this barrier requires continuous cell proliferation and differentiation. Moreover, these processes must be balanced to produce a normal epidermis. The stem cells of the epidermis reside in specific locations in the basal epidermis, hair follicle and sebaceous glands and these cells are responsible for replenishment of this tissue.

SCOPE OF REVIEW

A great deal of effort has gone into identifying protein epitopes that mark stem cells, in identifying stem cell niche locations, and in understanding how stem cell populations are related. We discuss these studies as they apply to understanding normal epidermal homeostasis and skin cancer.

MAJOR CONCLUSIONS

An assortment of stem cell markers have been identified that permit assignment of stem cells to specific regions of the epidermis, and progress has been made in understanding the role of these cells in normal epidermal homeostasis and in conditions of tissue stress. A key finding is the multiple stem cell populations exist in epidermis that give rise to different structures, and that multiple stem cell types may contribute to repair in damaged epidermis.

GENERAL SIGNIFICANCE

Understanding epidermal stem cell biology is likely to lead to important therapies for treating skin diseases and cancer, and will also contribute to our understanding of stem cells in other systems. This article is part of a Special Issue entitled Biochemistry of Stem Cells.

Stem cells of the human epidermis and their niche: composition and function in epidermal regeneration and carcinogenesis

Skin, as the largest organ, has long been subject of excellent and pioneering studies on stem cells and their role in tissue regulation and tumor formation. In particular, intensive research on mouse skin, and here especially the hair follicle, has largely extended our knowledge. Surprisingly, human skin, although the most easily accessible tissue in man, is far less conceived with regard to its stem cells and their specific environment (the niche). In consequence, these features are as yet only insufficiently defined and it still has to be elucidated how insights in cutaneous stem cell biology gained in mice can be extrapolated to humans. In the last few years, human model systems such as humanized mice or in vitro organotypic cultures that support maintenance or reconstruction of human skin and long-term epidermal regeneration have been developed. These models allow lineage tracing experiments and can be modified by adopting genetically manipulated cell types. Accordingly, they represent proper tools for human stem cell research and will clearly help to improve our still incomplete understanding. Like normal skin, the non-melanoma skin cancers and their respective tumors have gained considerable interest in basic as well as in clinical research. Being the most frequent human tumors globally, basal cell carcinomas and cutaneous squamous cell carcinomas (SCCs) continue to increase in incidence and specifically SCCs predominate in immunosuppressed transplant recipients. This review intends to compile the present knowledge on keratinocyte stem cells and their niches in normal skin and skin carcinomas with a special focus on the human situation. In particular, the role of the microenvironment, the niche, is emphasized, promoting our view of the decisive importance of the niche as a key regulatory element for controlling position, fate and regenerative potential of the stem cell population both in healthy skin and in carcinomas.

Correlation of Global MicroRNA Expression With Basal Cell Carcinoma Subtype

Basal cell carcinomas (BCCs) are the most common cancers in the United States. The histologic appearance distinguishes several subtypes, each of which can have a different biologic behavior. In this study, global miRNA expression was quantified by high-throughput sequencing in nodular BCCs, a subtype that is slow growing, and infiltrative BCCs, aggressive tumors that extend through the dermis and invade structures such as cutaneous nerves. Principal components analysis correctly classified seven of eight infiltrative tumors on the basis of miRNA expression. The remaining tumor, on pathology review, contained a mixture of nodular and infiltrative elements. Nodular tumors did not cluster tightly, likely reflecting broader histopathologic diversity in this class, but trended toward forming a group separate from infiltrative BCCs. Quantitative polymerase chain reaction assays were developed for six of the miRNAs that showed significant differences between the BCC subtypes, and five of these six were validated in a replication set of four infiltrative and three nodular tumors. The expression level of miR-183, a miRNA that inhibits invasion and metastasis in several types of malignancies, was consistently lower in infiltrative than nodular tumors and could be one element underlying the difference in invasiveness. These results represent the first miRNA profiling study in BCCs and demonstrate that miRNA gene expression may be involved in tumor pathogenesis and particularly in determining the aggressiveness of these malignancies.