The value of ACTN1 in the diagnosis of cutaneous squamous cell carcinoma: A continuation study.

Abstract

Cutaneous squamous cell carcinoma (CSCC) originates from epidermal keratinocytes or adnexal structures, including eccrine glands and (or) pilosebaceous units. CSCC is the second most common nonmelanoma skin cancer, and its incidence has increased in recent years. According to several studies reported, about 15–35 per 100 000 individuals are diagnosed with CSCC each year, and the incidence of CSCC is expected to increase by 2%−4% per year.1 On the other hand, the incidence of primary CSCC has increased by 50%−300% globally, especially among Caucasian populations in New Zealand, Australia, and North America over the last 3 decades.2 Although the early-stage CSCC usually has a good prognosis, the metastatic CSCC can be difficult to treat. Bowen's disease is also known as squamous cell carcinoma in situ. It is estimated that in general population around 3%–5% of Bowen's disease transform into invasive CSCC.3 In recent years, a variety of studies have been devoted to exploring the molecular mechanism and target proteins of the progression of in situ carcinoma to invasive CSCC via omics methods.4-6 Besides, the lesions appearance of the Bowen's disease and CSCC were similar and not indistinguishable. Therefore, the histopathological examination results, the only gold standard for evaluating Bowen's disease progression to CSCC. In addition, early assessment of Bowen's disease progression to CSCC is particularly important for treatment methods options. According to our previous investigated, when compared with lesions of Bowen's disease, the Tenascin C (TNC), FSCN1, SERPINB1, ACTN1, and RAB31 in CSCC tissues were significantly upregulated, while COL3A1, COL1A1, and CD36 were significantly downregulated.6 However, the serum levels of these proteins in CSCC was unclear, and in the present study, we explored the serum levels of these proteins differences in CSCC relative to Bowen's disease. We also discussed the diagnostic value of these proteins expression in CSCC. In this study, a total of 55 patients were diagnosed with CSCC (CSCC group) in the Department of Dermatology, Yijishan Hospital and the First Affiliated Hospital of Xinxiang Medical University between January 2020 and January 2022 were enrolled. All patients were diagnosed with CSCC according to histopathological examination findings. The patients with CSCC comprised 27 males (49.09%) and 28 females (50.91%) aged between 39 and 69 years, with an average age of 52.29 ± 5.88 years. The CSCC patients with first diagnosed and never treated with any biological agents such as programmed cell death protein 1. On the other hand, 40 patients with Bowen's disease (BD group) and 30 healthy volunteers (Control group) were also included in this study: These 70 individuals, with no history of severe infections and malignant tumors, in the same period were enrolled. The BD group comprised 22 males (55.00%) and 18 females (45.00%) aged between 44 and 61 years, with an average age of 53.55 ± 4.56 years. The control group comprised 16 males (53.33%) and 14 females (46.67%) aged between 41 and 66 years, with an average age of 50.30 ± 6.39 years. There was no significant difference in gender and age among the three groups (p > 0.05). The clinical baseline characteristics of three groups are shown in Table S1. All individuals signed the informed consent. The serum levels of TNC (Abcam), FSCN1 (AssayGenie), SERPINB1 (AssayGenie), ACTN1 (AssayGenie), RAB31 (Abbexa), COL3A1 (AssayGenie), COL1A1 (AssayGenie), and CD3 (AssayGenie) were measured by an enzyme-linked immuno sorbent assay kit. The minimum-to-maximum detection limits were (93.7∼6000) pg/ml for TNC, (0.78∼50) ng/ml for FSCN1, (0.313∼20) ng/ml for SERPINB1, (0.156∼10) ng/ml for ACTN1, (0.156∼10) ng/ml for RAB31, (31.25∼2000) ng/ml for COL3A1, (0.313∼20) ng/ml for COL1A1, and (0.156∼10) ng/ml for CD36. On the other hand, the transcriptomic data of CSCC (GSE45216) were selected and downloaded from the GEO database (https://www.ncbi.nlm.nih.gov/pmc/). In GSE45216, a total of 30 samples with CSCC (GSM1099226∼GSM1099255) and 10 samples with Actinic keratosis (GSM1099256∼GSM1099265) were selected and enrolled. Actinic keratosis, similar with Bowen's disease, is a common premalignant skin lesion characterized by itraepithelial keratinocyte dysplasia and molecular alterations shared with CSCC. Clinically, the majority of patients with AK will evolve into CSCC.7 The RNA was extracted by laser capture microdissection from 10 Actinic keratosis and 30 CSCC, for analysis using the Affymetrix HG U133 Plus 2.0 microarrays. The transcriptomic data were calculated using GEO2R online (https://www.ncbi.nlm.nih.gov/geo/geo2r/). The differentially expressed transcriptomic data between CSCC and AK were further identified using a log2FC > 1/ ← 1 and adjusted p values < 0.05. Importantly, the GSE45216 was used to validate the target protein expression value difference between CSCC and AK. According to our results, we only found the expression levels of SERPINB1 and ACTN1 in serum of patients with CSCC were significantly higher than that of Bowen's disease (p < 0.05). The data were presented in Figure S1. Furthermore, the results were furthered validation in GSE45216, and we confirmed that the ACTN1 expression value in CSCC was significantly higher than that of Actinic keratosis (p < 0.05). The data are presented in Figure 1. Combined with the above results, we proved that the ACTN1 was a biomarker protein of the progression of in situ carcinoma to invasive CSCC. On the other hand, the receiver operating characteristic curve was drawn to analyze the efficacy of the serum ACTN1 expression value in the diagnosis of CSCC. The areas under the curve of ACTN1 for the diagnosis of CSCC were 0.841. The sensitivity and specificity were 86.40% and 82.50%, respectively. The data are presented in Figure S2. The association between ACTN1 expression level and clinicopathologic features in patients with CSCC was analyzed. The serum expression level of ACTN1 was related to the primary tumor diameter, tumor cell differentiation degree and invasion depth (p < 0.05). The results are showed in Table 1. CSCC in situ is also known as Bowen's disease. If left untreated, Bowen's disease may progress to invasive CSCC with the incidence of 3%–5%.8 The exact mechanisms by which Bowen's disease progresses to CSCC are complicated and merits more attention. ACTN1, an actin cross-linking protein, it is involved in the tumorigenesis and development of certain cancers. Previous study indicated that the ACTN1 regulates the epithelial-mesenchymal transition and tumorigenesis of gastric cancer via the AKT/GSK3 β/β-catenin pathway.9 Besides, the ACTN1 is also over-expressed in hepatocellular carcinoma tissues by suppressing Hippo signaling via physical interaction with MOB1.10 On the other hand, higher ACTN1 protein levels were significantly associated with poor prognosis in Oral Squamous Cell Carcinoma.11 Therefore, our results suggested that ACTN1 acts as tumor promoter and also serve as a diagnostic biomarker of Bowen's disease progression to CSCC. However, the exact mechanism of ACTN1 regulates CSCC progression still needs to be elucidated. The authors thank all our colleagues working at the Department of Dermatology, Yijishan Hospital, the First Affiliated Hospital of Wannan Medical college. They also thank their good friend (HU Hua, Department of Dermatology, the First Affiliated Hospital of Xinxiang Medical University) for samples support. This work was supported by Doctoral Research Start-up Funding from Yijishan Hospital, the first affiliated hospital of Wannan Medical College (grant numbers: YR202204 and YR202216), The Key Research Project of Wannan Medical College in 2022 (grant number: WK2022ZF09), 2021 Natural Science Research Project of Universities from Anhui Province (grant number: KJ2021ZD0097), and 2021 Health Commission Project of Anhui Province (grant number: AHWJ2021a005). The authors declare that they have no competing interests. All study participants signed an informed consent form prior to participation. All authors gave their consent for publication. All the data for this study will be made available upon reasonable request to the corresponding author. Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. Any queries (other than missing content) should be directed to the corresponding author for the article.