Cutaneous squamous cell carcinoma (cuSCC) comprises 15–20% of all skin cancers, accounting for over 700,000 cases in USA annually. Most cuSCC arise in association with a distinct precancerous lesion, the actinic keratosis (AK). To identify potential targets for molecularly targeted chemoprevention, here we perform integrated cross-species genomic analysis of cuSCC development through the preneoplastic AK stage using matched human samples and a solar ultraviolet radiation-driven Hairless mouse model. We identify the major transcriptional drivers of this progression sequence, showing that the key genomic changes in cuSCC development occur in the normal skin to AK transition. Our data validate the use of this ultraviolet radiation-driven mouse cuSCC model for cross-species analysis and demonstrate that cuSCC bears deep molecular similarities to multiple carcinogen-driven SCCs from diverse sites, suggesting that cuSCC may serve as an effective, accessible model for multiple SCC types and that common treatment and prevention strategies may be feasible.

Recessive dystrophic epidermolysis bullosa (RDEB) is a rare inherited skin and mucous membrane fragility disorder complicated by early-onset, highly malignant cutaneous squamous cell carcinomas (SCCs). The molecular etiology of RDEB SCC, which arises at sites of sustained tissue damage, is unknown. We performed detailed molecular analysis using whole-exome, whole-genome, and RNA sequencing of 27 RDEB SCC tumors, including multiple tumors from the same patient and multiple regions from five individual tumors. We report that driver mutations were shared with spontaneous, ultraviolet (UV) light-induced cutaneous SCC (UV SCC) and head and neck SCC (HNSCC) and did not explain the early presentation or aggressive nature of RDEB SCC. Instead, endogenous mutation processes associated with apolipoprotein B mRNA-editing enzyme catalytic polypeptide-like (APOBEC) deaminases dominated RDEB SCC. APOBEC mutation signatures were enhanced throughout RDEB SCC tumor evolution, relative to spontaneous UV SCC and HNSCC mutation profiles. Sixty-seven percent of RDEB SCC driver mutations was found to emerge as a result of APOBEC and other endogenous mutational processes previously associated with age, potentially explaining a >1000-fold increased incidence and the early onset of these SCCs. Human papillomavirus-negative basal and mesenchymal subtypes of HNSCC harbored enhanced APOBEC mutational signatures and transcriptomes similar to those of RDEB SCC, suggesting that APOBEC deaminases drive other subtypes of SCC. Collectively, these data establish specific mutagenic mechanisms associated with chronic tissue damage. Our findings reveal a cause for cancers arising at sites of persistent inflammation and identify potential therapeutic avenues to treat RDEB SCC.

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Overexpression and activation of c-Jun N-terminal kinases (JNKs) have been observed in multiple cancer cell lines and tumor samples. Various JNK isoforms have been reported to promote lung and liver cancer, as well as keratinocyte transformation, suggesting an important role of JNK signaling in promoting tumor development. However, there are three JNK isoforms, and it is unclear how each individual isoform, especially the ubiquitously expressed JNK1 and JNK2, functions in melanoma. Our previous study found that C116S mutations in both JNK1 and JNK2 rendered them insensitive to the covalent pan-JNK inhibitor JNK-IN-8 while retaining kinase activity. To delineate the specific roles of JNK1 and JNK2 in melanoma cell proliferation and invasiveness, we expressed the wild type (WT) and C116S mutants in melanoma cell lines and *

Tyrosine is mainly degraded in the liver by a series of enzymatic reactions. Abnormal expression of the tyrosine catabolic enzyme tyrosine aminotransferase (TAT) has been reported in patients with hepatocellular carcinoma (HCC). Despite this, aberration in tyrosine metabolism has not been investigated in cancer development. In this work, we conduct comprehensive cross-platform study to obtain foundation for discoveries of potential therapeutics and preventative biomarkers of HCC. We explore data from The Cancer Genome Atlas (TCGA), Gene Expression Omnibus (GEO), Gene Expression Profiling Interactive Analysis (GEPIA), Oncomine and Kaplan Meier plotter (KM plotter) and performed integrated analyses to evaluate the clinical significance and prognostic values of the tyrosine catabolic genes in HCC. We find that five tyrosine catabolic enzymes are downregulated in HCC compared to normal liver at mRNA and protein level. Moreover, low expression of these enzymes correlates with poorer survival in patients with HCC. Notably, we identify pathways and upstream regulators that might involve in tyrosine catabolic reprogramming and further drive HCC development. In total, our results underscore tyrosine metabolism alteration in HCC and lay foundation for incorporating these pathway components in therapeutics and preventative strategies.

Cutaneous squamous cell carcinoma (cuSCC) is the second most common skin cancer and commonly arises in chronically UV-exposed skin or chronic wounds. Since UV exposure and chronic wounds are the two most prominent environmental factors that lead to cuSCC initiation, we undertook this study to test whether more acute molecular responses to UV and wounding overlapped with molecular signatures of cuSCC. We reasoned that transcriptional signatures in common between acutely UV-exposed skin, wounded skin, and cuSCC tumors, might enable us to identify important pathways contributing to cuSCC. We performed transcriptomic analysis on acutely UV-exposed human skin and integrated those findings with datasets from wounded skin and our transcriptomic data on cuSCC using functional pair analysis, GSEA, and pathway analysis. Integrated analyses revealed significant overlap between these three datasets, thus highlighting deep molecular similarities these biological processes, and we identified Oncostatin M (OSM) as a potential common upstream driver. Expression of OSM and its downstream targets correlated with poorer overall survival in head and neck SCC patients. In vitro, OSM promoted invasiveness of keratinocytes and cuSCC cells and suppressed apoptosis of irradiated keratinocytes. Together, these results support the concept of using an integrated, biologically-informed approach to identify potential promoters of tumorigenesis.

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Ginsenoside Rg3 is a natural active ingredient that is extracted from Korean red ginseng root. It elevates the therapeutic effect of radiotherapy and chemotherapy, but previous studies found that the application of Rg3 is heavily limited by its low bioavailability and poor absorption via oral administration.To overcome these problems, Rg3-loaded PEG-PLGA-NPs (Rg3-NPs) were prepared by the modified spontaneous emulsification solvent diffusion (SESD) method, and the physicochemical characteristics of Rg3-NPs were investigated. We treated primary glioblastoma with 50 mM Rg3-NPs for 48h. We then used gene expression arrays (Illumina) for genome-wide expression analysis and validated the results for genes of interest by means of real-time PCR. Functional annotations were then performed using the DAVID and KEGG online tools. The results showed that the Rg3-NPs are slick and uniform, the average diameter of the nanoparticles is 75-90 nm, and their entrapment efficiency is 89.7 + 1.7%. MTT showed that the growth of cells can be significantly inhibited by Rg3-NPs in a dose-dependent manner. FCM testing showed Rg3-NPs can be released from the conjugate nanoparticle and react with the genes in the cell nuclei, causing changes in the gene molecules. We also found that cancer cells treated with Rg3-NPs undergo cell-cycle arrest at different checkpoints. This arrest was associated with a decrease in the mRNA levels of core regulatory genes BUB1, CDC20, TTK, and CENPE, as determined by microarray analysis and verified by real-time PCR. Furthermore, Rg3-NPs induced the expression of the apoptotic and antimigratory protein p53 in cell lines. The results of the present study, together with the results of earlier studies, show that Rg3-NPs target genes involved in the progression of the M-phase of the cell cycle. It is associated with several important pathways, which include apoptosis (p53). Rg3-NPs may be a potent cell-cycle regulation drug targeting the M-phase in glioblastoma cell lines.