Immunoreactivity for alpha-smooth muscle actin characterizes a potentially aggressive subgroup of little basal cell carcinomas

Evaluation of Immunohistochemical Findings and Clinical Features Associated with Local Aggressiveness in Basal Cell Carcinoma

Background & Objective:

Basal cell carcinoma (BCC) is classified into BCC1 or low risk (nodular, superficial type) and BCC2 or high risk (micronodular, morpheaform, infiltrative, and basosquamous types) based on clinical behavior. This study attempts to evaluate immunohistochemical (IHC) findings and clinical features associated with local aggressiveness and recurrence in BCC lesions.

Methods:

This is a cross-sectional descriptive study conducted on 42 paraffin blocks (22 BCC1, 20 in BCC2) at Pathology Department of Afzalipour Teaching Hospital. First, demographic features of the patients were recorded and pathology blocks were classified by two dermatopathologists based on histopathological types of BCC1 and BCC2. Then, primary monoclonal antibodies including CD10, CD1a, SMA, Ki67, CD34, and P53 were utilized for IHC study. We compared BCC1 and BCC2 according to IHC markers, demographic features of patients, and tumoral features.

Results:

The mean number of Langerhans cells (LCs) within epidermis above tumor mass was 14+1.92 and 4.7±1.23 in BCC1 and BCC2, respectively; these results show a significant difference between the two groups (P=0.001). P53 was positive in 41.13±6.39% and 74.5 ±6.26% of the tumor cells in BCC1 and BCC2 groups, which was statistically significant (P=0.001). Also, the mean number of blood vessels was 14.40±1.30 and 21.40±1.97 in BCC1 and BCC2, that was statistically significant (P=0.005).

Conclusion:

Higher numbers of angiogenesis (SMA positive) and positive P53 were observed in BCC2 than BCC1. Also, more active positive CD1a cells were observed in BCC1 compared to BCC2.

Expression patterns of α2,3-sialyltransferase I and α2,6-sialyltransferase I in human cutaneous epithelial lesions

Skin tumors have become one of the most common cancers in the world and their carcinogenesis is frequently associated with altered glycosylation patterns. The aberrant sialylation, a type of glycosylation, can mediate pathophysiological key events during various stages of tumor progression, including invasion and metastasis. Sialyltransferases play a key role in a variety of biological processes, including cell-cell communication, cell-matrix interaction, adhesion, and protein targeting. In this study, it was evaluated the expression of ST3Gal I and ST6Gal I in cutaneous epithelial lesions that include actinic keratosis (n=15), keratoacanthoma (n=9), squamous cell carcinoma (n=22) and basal cell carcinoma (n=28) in order to evaluate if sialyltransferases expression is different in premalignant and in malignant tumors. The expression of ST3Gal I was observed in actinic keratosis (53%), keratoacanthoma (78%), squamous cell carcinoma (73%) and basal cell carcinoma (32%) with statistic differences between basal cell carcinoma and keratoacanthoma (P=0.0239) and basal cell carcinoma and squamous cell carcinoma (P=0.0096); for ST6Gal I, cytoplasmic expression was noted in actinic keratosis (40%), heterogeneous and cytoplasmic expression was noted in keratoacanthoma (67%), squamous cell carcinoma (41%) and basal cell carcinoma (7%) with statistic differences between basal cell carcinoma and squamous cell carcinoma (P=0.0061) and basal cell carcinoma and keratoacanthoma (P=0.0008). In summary, our results showed that the high expression of ST3Gal I and ST6Gal I, in skin tumors, is associated with tumors with greater potential for invasion and metastasis, as in the case of squamous cell carcinoma, and this may be related to their behavior.

Identifying pathological biomarkers: histochemistry still ranks high in the omics era

In recent years, omic analyses have been proposed as possible approaches to diagnosis, in particular for tumours, as they should be able to provide quantitative tools to detect and measure abnormalities in gene and protein expression, through the evaluation of transcription and translation products in the abnormal vs normal tissues. Unfortunately, this approach proved to be much less powerful than expected, due to both intrinsic technical limits and the nature itself of the pathological tissues to be investigated, the heterogeneity deriving from polyclonality and tissue phenotype variability between patients being a major limiting factor in the search for unique omic biomarkers. Especially in the last few years, the application of refined techniques for investigating gene expression in situ has greatly increased the diagnostic/prognostic potential of histochemistry, while the progress in light microscopy technology and in the methods for imaging molecules in vivo have provided valuable tools for elucidating the molecular events and the basic mechanisms leading to a pathological condition. Histochemical techniques thus remain irreplaceable in pathologist's armamentarium, and it may be expected that even in the future histochemistry will keep a leading position among the methodological approaches for clinical pathology.

Histochemistry through the years, browsing a long-established journal: novelties in traditional subjects

Histochemical journals represent a traditional forum where methodological and technological improvements can be presented and validated in view of their applications to investigate not only cytology and histology in normal and diseased conditions but to test as well hypotheses on more basic issues for life sciences, such as comparative and evolutionary biology. The earliest scientific journals on histochemistry began their publication in the first half of the ‘50s of the last century, and their readership did not probably change over the years; rather, the authors’ interests may have progressively been changing as well as the main topics of their articles. This hypothesis is discussed, based on the subjects of the article published in the first and last ten years in the European Journal of Histochemistry, as an example of old journal which started publication in 1954, being since then the official organ of the Italian Society of Histochemistry. This survey confirmed that histochemistry has provided and still offers unique opportunities for studying the structure, chemical composition and function of cells and tissues in a wide variety of living organisms, especially when the topological distribution of specific molecular components has diagnostic or predictive significance, as it occurs in human and veterinary biology and pathology. Some subjects (e.g. histochemistry applied to muscle cells or to mineralized tissues) have recently become rather popular, whereas a wider application of the histochemical approach may be envisaged for plant cells and tissues.