Decreased Sox2 Messenger RNA Expression in Basal Cell Carcinoma

An integrative bioinformatics investigation and experimental validation of critically involved genes in high-grade gliomas

Background

Lack of knowledge around underlying mechanisms of gliomas mandates intense research efforts to improve the disease outcomes. Identification of high-grade gliomas pathogenesis which is known for poor prognosis and low survival is of particular importance. Distinguishing the differentially expressed genes is one of the core approaches to clarify the causative factors.

Methods

Microarray datasets of the treatment-naïve gliomas were provided from the Gene Expression Omnibus considering the similar platform and batch effect removal. Interacting recovery of the top differentially expressed genes was performed on the STRING and Cytoscape platforms. Kaplan–Meier analysis was piloted using RNA sequencing data and the survival rate of glioma patients was checked considering selected genes. To validate the bioinformatics results, the gene expression was elucidated by real-time RT-qPCR in a series of low and high-grade fresh tumor samples.

Results

We identified 323 up-regulated and 253 down-regulated genes. The top 20 network analysis indicated that PTX3, TIMP1, CHI3L1, LTF and IGFBP3 comprise a crucial role in gliomas progression. The survival was inversely linked to the levels of all selected genes. Further analysis of RNA sequencing data indicated a significant increase in all five genes in high-grade tumors. Among them, PTX3, TIMP1 and LTF did not show any change in low-grade versus controls. Real-time RT-qPCR confirmed the in-silico results and revealed significantly higher expression of selected genes in high-grade samples compared to low-grade.

Conclusions

Our results highlighted the role of PTX3 and TIMP1 which were previously considered in glioma tumorigenesis as well as LTF as a new potential biomarker.

Immunohistochemical expression of SOX2 in non-melanoma skin cancer

BACKGROUND

Basal cell carcinoma (BCC) followed by squamous cell carcinoma (SCC) are the most common non-melanoma skin cancer (NMSC). SOX2 is a transcription factor that acts on various phases of embryonic development and its overexpression in many tumors has been reported.

AIM

This work aimed to evaluate the possible role of SOX2 in pathogenesis of non-melanoma skin cancer through its immunohistochemical assessment in BCC and SCC compared to normal skin and correlating its expression with the established prognostic factors.

METHODS

The investigated cases were 24 BCC, 21 SCC, and 26 normal skin specimens.

RESULTS

SOX2 was not expressed in normal skin, but it was upregulated in SCC (85.7%) and BCC (66.7%), with a significant difference between malignant cases and normal skin (p < 0.001). However, SOX2 expression did not differ between SCC and BCC. SOX2 expression was associated with large-sized tumors in all malignant cases (BCC plus SCC) (p = 0.02) and in SCC (p = 0.043) alone together with its liability to be expressed in advanced stage in SCC (p = 0.063).

CONCLUSIONS

SOX2 was over-expressed in cutaneous SCC and BCC without a significant difference. SOX2 may enhance progression of NMSC manifested by its association with large tumor size and advanced stage.