Clinical analysis of 10 cases with subcutaneous panniculitis-like T-cell lymphoma and tissue AURKA expression.

BACKGROUND: Due to its rarity, subcutaneous panniculitis-like T-cell lymphoma (SPTCL) is often misdiagnosed as benign panniculitis, and there are no standardized treatment guidelines for SPTCL. Aurora kinase A (AURKA) plays a regulatory role in both mitosis and meiosis. Cells treated with an AURKA inhibitor showed severe mitotic delay, which triggered apoptosis. MATERIALS AND METHODS: Ten cases of SPTCL were collected in this study, and immunohistochemistry was performed to detect AURKA expression in the skin tissues of these cases. Control groups were set as follows: 1) 10 cases of inflammatory panniculitis; 2) 9 healthy individuals. Fisher's exact test was used to compare the positive rates of AURKA among various groups. RESULTS: An average onset age of 27.3 years was found in 10 SPTCL cases. Clinically, these patients primarily presented with multiple subcutaneous nodules on the trunk and lower extremities, accompanied by intermittent high fever. One case showed lymph node metastasis, while no other distant organ metastasis being observed in any case. Pathologically, there was an infiltration of a large number of atypical lymphocytes within the fat lobules, characterized as a cytotoxic type. AURKA stanning was positive in 6 out of 10 SPTCL cases, while no positive cases were found in the control groups. CONCLUSION: 1) SPTCL predominantly affects young individuals and can be identified by nodular erythema on the trunk, intermittent high fever, and infiltration of atypical cytotoxic lymphocytes within fat lobules. 2) For early-stage cases without metastasis, monotherapy with glucocorticoids or immunosuppressants such as cyclosporine can be considered. 3) High expression of AURKA in SPTCL tissues suggests that AURKA could be a potential biomarker for disease diagnosis, providing a theoretical basis for further targeted therapy.

GADD45G Interacts with E-cadherin to Suppress the Migration and Invasion of Esophageal Squamous Cell Carcinoma.

BACKGROUND/AIMS: Esophageal squamous cell carcinoma (ESCC) is one of the most prevalent cancers with poor prognosis. Metastasis is the leading cause of cancer-related deaths. The growth arrest and DNA damage-inducible 45 gamma (GADD45G) has been reported to correlate with survival, invasion, and metastasis of ESCC. This study was aimed to investigate the role and mechanism of GADD45G in ESCC cell migration and invasion. METHODS: Both the effects of GADD45G and its need for E-cadherin to function on ESCC cell migration and invasion were determined through loss- and gain-of-function approaches via Transwell assays. The interaction between GADD45G and E-cadherin was detected by GST-pull down and IP assays. The expression of E-cadherin upon GADD45G overexpression was evaluated by RT-qPCR and western blot. The level of E-cadherin in cytoplasmic, nuclear, and membrane fractions was examined by western blot following subcellular fractionation. RESULTS: Knockdown of GADD45G increased the migration and invasion abilities of KYSE150 cells, while overexpression of GADD45G showed the opposite effects on YES2 and KYSE30 cells. GADD45G could interact with E-cadherin and enhanced its membrane level. Knockdown of E-cadherin abolished the inhibitory effects of GADD45G on ESCC cell migration and invasion. Intriguingly, dimer-dissociating mutant of GADD45G could not interact with E-cadherin and almost lost its ability to suppress the ESCC cell migration and invasion. CONCLUSIONS: This study reveals a novel role for GADD45G in inhibiting the ESCC cell migration and invasion, which will provide a new insight in understanding the ESCC metastatic mechanism.

FAT1, a direct transcriptional target of E2F1, suppresses cell proliferation, migration and invasion in esophageal squamous cell carcinoma.

OBJECTIVE: Growing evidence indicates that FAT atypical cadherin 1 (FAT1) has aberrant genetic alterations and exhibits potential tumor suppressive function in esophageal squamous cell carcinoma (ESCC). However, the role of FAT1 in ESCC tumorigenesis remains not well elucidated. The aim of this study was to further investigate genetic alterations and biological functions of FAT1, as well as to explore its transcriptional regulation and downstream targets in ESCC. METHODS: The mutations of FAT1 in ESCC were achieved by analyzing a combined study from seven published genomic data, while the copy number variants of FAT1 were obtained from an analysis of our previous data as well as of The Cancer Genome Atlas (TCGA) and Cancer Cell Line Encyclopedia (CCLE) databases using the cBioPortal. The transcriptional regulation of FAT1 expression was investigated by chromatin immunoprecipitation (ChIP) and the luciferase reporter assays. In-cell western, Western blot and reverse transcription-quantitative polymerase chain reaction (RT-qPCR) were used to assess the indicated gene expression. In addition, colony formation and Transwell migration/invasion assays were employed to test cell proliferation, migration and invasion. Finally, RNA sequencing was used to study the transcriptomes. RESULTS: FAT1 was frequently mutated in ESCC and was deleted in multiple cancers. Furthermore, the transcription factor E2F1 occupied the promoter region of FAT1, and depletion of E2F1 led to a decrease in transcription activity and mRNA levels of FAT1. Moreover, we found that knockdown of FAT1 promoted KYSE30 and KYSE150 cell proliferation, migration and invasion; while overexpression of FAT1 inhibited KYSE30 and KYSE410 cell proliferation, migration and invasion. In addition, knockdown of FAT1 led to enrichment of the mitogen-activated protein kinase (MAPK) signaling pathway and cell adhesion process. CONCLUSIONS: Our data provided evidence for the tumor suppressive function of FAT1 in ESCC cells and elucidated the transcriptional regulation of FAT1 by E2F1, which may facilitate the understanding of molecular mechanisms of the progression of ESCC.