Single-cell sequencing highlights heterogeneity and malignant progression in actinic keratosis and cutaneous squamous cell carcinoma.

Cutaneous squamous cell carcinoma (cSCC) is the second most frequent of the keratinocyte-derived malignancies with actinic keratosis (AK) as a precancerous lesion. To comprehensively delineate the underlying mechanisms for the whole progression from normal skin to AK to invasive cSCC, we performed single-cell RNA sequencing (scRNA-seq) to acquire the transcriptomes of 138,982 cells from 13 samples of six patients including AK, squamous cell carcinoma in situ (SCCIS), cSCC, and their matched normal tissues, covering comprehensive clinical courses of cSCC. We identified diverse cell types, including important subtypes with different gene expression profiles and functions in major keratinocytes. In SCCIS, we discovered the malignant subtypes of basal cells with differential proliferative and migration potential. Differentially expressed genes (DEGs) analysis screened out multiple key driver genes including transcription factors along AK to cSCC progression. Immunohistochemistry (IHC)/immunofluorescence (IF) experiments and single-cell ATAC sequencing (scATAC-seq) data verified the expression changes of these genes. The functional experiments confirmed the important roles of these genes in regulating cell proliferation, apoptosis, migration, and invasion in cSCC tumor. Furthermore, we comprehensively described the tumor microenvironment (TME) landscape and potential keratinocyte-TME crosstalk in cSCC providing theoretical basis for immunotherapy. Together, our findings provide a valuable resource for deciphering the progression from AK to cSCC and identifying potential targets for anticancer treatment of cSCC.

[Effect of turmeric volatile oil on proliferation and apoptosis of human skin SCC A431 cells].

To investigate the effect of turmeric volatile oil (TVO) on the apoptosis and proliferation of human skin SCC A431 cells, A431 cells were incubated with different concentrations (5-80 mg•L⁻¹) of TVO in vitro．The proliferation and cell cycle were assessed by CCK8 assay. The change of morphology was observed with inverted microscope. Apoptosis was evaluated with AO/EB double staining and flow cytometry (FCM); cell cycle was analyzed with FCM ．Western blot method was used to detect caspase-3 and caspase-9 protein expression. Results indicated that TVO has significant inhibitory effects on the growth of A431 cells in a dose dependent relationship, the difference between groups has statistically significant (P<0.05). TVO group compared with control group, concentrations in cells shrivel and broken phenomenon, cell apoptosis rate increased, and a dose dependent and increased the expression of caspase-3 and caspase-9. The experiment results suggested that TVO could restrain skin squamous carcinoma A431 cells proliferation, and induce its apoptosis. The mechanism may be related to increase the expression of caspase-3 and caspase-9.