Estrogen receptor subtype agonist activation in human cutaneous squamous cell carcinoma cells modulates expression of CD55 and Cyclin D1

KS-cSCC-1 and KS-cSCC-2: two novel cutaneous squamous cell carcinoma cell lines established from Japanese patients

Introduction

Cutaneous squamous cell carcinoma (cSCC) is a common form of skin cancer. Less accessibility to the cSCC cell lines has limited analyses of this disease. Thus, we here aimed to establish novel cSCC cell lines from patient's cSCC lesions.

Methods

Two novel cSCC cell lines (named KS-cSCC-1 and KS-cSCC-2) were established from an axillary lymph node metastasis of a Japanese female and an inguinal lymph node metastasis of a Japanese male. The characteristics of the established cell lines were assessed by in vitro analyses.

Results

The cells were successfully maintained for more than 9 months, with a doubling time of 47.5 ± 1.11 h (KS-cSCC-1) and 39.2 ± 5.78 h (KS-cSCC-2). The cell lines exhibited constant growth, spheroid formation, and invasiveness. Short tandem repeat analyses and immunohistochemistry confirmed that both cell lines are identical to their original tumor. The KS-cSCC-1 cells were weakly positive for CK14 and strongly positive for CK10, while the KS-cSCC-2 showed opposite expression patterns. Chemosensitivity of the cell lines was further tested and the cells were sensitive to anticancer drugs which are used to treat cSCC.

Conclusion

The KS-cSCC-1 and KS-cSCC-2 cell lines were promising resources for basic and preclinical research on cSCC to better define the tumor characteristics and treatment strategy of this cancer.

Suppressing Expression of SERPINE1/PAI1 Through Activation of GPER1 Reduces Progression of Vulvar Carcinoma

BACKGROUND/AIM

The serine proteinase inhibitor 1 (SERPINE1) gene codes for the plasminogen activator inhibitor 1 (PAI1) protein and is thought to play a tumor supportive role in various cancers. In this work we aimed to uncover the role PAI1 plays in the proliferation, migration, and invasion of vulvar cancer (VC), and define the protein's function as an oncogene or tumor suppressor.

MATERIALS AND METHODS

Through treatment with an agonist (G1) and antagonist (G36) of G-coupled estrogen receptor 1 (GPER1), an upstream regulator of SERPINE1 expression, and a forward transfection knockdown protocol, the expression of SERPINE1/PAI1 in VC cells was altered. The effects these altered SERPINE1/PAI1 levels had on tumor cell functions were then examined. Proliferation was analyzed using the resazurin assay, while migration was studied via the gap closure assay. Through colony- and tumor sphere- formation assays clonogenicity was tested, and western blots showed protein expression.

RESULTS

In A431 VC cells, when the levels of PAI1 were reduced via knockdown or treatment with G1, migration, proliferation, and colony growth was reduced. Treatment with G36 increased expression of PAI1 and increased migration and colony size in CAL39 cells.

CONCLUSION

Based on the findings in this study, suppressing PAI1 expression in VC cells appears to reduce their progression and tumorigenic potential. Therefore, PAI1 could possibly function as an oncogene in VC. GPER1 appears to be a suitable target for suppressing PAI1 in VC.

Sex disparity in skin carcinogenesis and potential influence of sex hormones

Background

Sex or gender disparity in skin cancer has been documented for a long time at the population level. UV radiation (UVR) is a common environmental risk for all three major types of skin cancer: cutaneous melanoma (CM), basal cell carcinoma (BCC) and cutaneous squamous cell carcinoma (cSCC). The underlying mechanism for sex disparity has been largely attributed to sex‐differentiated behaviour patterns related to UVR. Non‐UVR factors such as intrinsic physiological differences have been suggested but remain understudied.

Aims, Materials and Methods

This review summarizes and compares the known sex differences in three skin cancer types with regard to body site distribution and age influence.

Results

We found a similar age‐dependent sex difference pattern in CM and BCC. Specifically, CM and BCC tend to show higher incidence in young women and old men, with a switching age around menopause. The switching age suggests involvement of sex hormones, which has shown controversial influence on skin cancers at epidemiological level. Literatures regarding sex hormone receptors for oestrogen, androgen and progesterone are summarized for potential explanations at molecular level.

Discussion

Overall, more and more evidence suggests non‐UVR factors such as sex hormones play critical roles in skin cancer (especially CM and BCC), yet solid population and molecular evidence are required. Incidences of skin cancer are increasing which suggests limited effect for the current UVR‐avoidance prevention methods.

Conclusion

Fully understanding the causes of sex disparities in incidence is necessary for developing a comprehensive prevention strategy.