HN1L/AP-2γ/PLK1 signaling drives tumor progression and chemotherapy resistance in esophageal squamous cell carcinoma.

Hematological and neurological expressed 1 like (HN1L) is a newly identified oncogene in lung cancer and hepatocellular carcinoma recently identified by our team, but its roles in the development and treatment of esophageal squamous cell carcinoma (ESCC) remain incompletely cataloged. Here, using ESCC tissue array and public database analysis, we demonstrated that HN1L was highly expressed in ESCC tissues, which was associated with tumor tissue invasion, poor clinical stage and short survival for ESCC patients. Loss- and gain-of-function studies in ESCC cells revealed that HN1L enhances ESCC cell metastasis and proliferation in vitro and in mice models. Moreover, high level of HN1L reduces the sensibility of ESCC cells to chemotherapeutic drugs, such as Docetaxel. Mechanism studies revealed that HN1L activated the transcription of polo-like kinase 1 (PLK1) by interacting with transcription factor AP-2γ, which increased the expression of malignancy related proteins Cyclin D1 and Slug in ESCC cells. Blocking PLK1 with inhibitor BI-2356 abrogated the oncogenic function of HN1L and significantly suppressed ESCC progression by combining with chemotherapy. Therefore, this study demonstrates the vital pro-tumor role of HN1L/AP-2γ/PLK1 signaling axis in ESCC, offering a potential therapeutic strategy for ESCC patients with high HN1L by blocking PLK1.

Huxie Huaji Ointment Induced Apoptosis of Liver Cancer Cells In Vivo and In Vitro by Activating the Mitochondrial Pathway.

Huxie Huaji (HXHJ) Ointment is a famous traditional Chinese medicinal prescription and is commonly used for the clinical treatment of hepatocellular carcinoma by boosting immunity and detoxification. However, the scientific evidence for the effect of HXHJ Ointment on hepatocellular carcinoma and the underlying molecular mechanism are lacking. The present study aimed to identify the effects of HXHJ Ointment on hepatocellular carcinoma in vitro and in vivo as well as investigating the mechanistic basis for the anticancer effect of HXHJ ointment. First, liquid chromatography-mass spectrometry was used to verify the composition of HXHJ Ointment and quality control. Second, in vitro, Cell Counting Kit (CCK8) cell viability assay and Hoechst 33342 staining assay were performed to explain the cell apoptosis. The protein levels of tumor suppressor protein (p53), B-cell lymphoma 2 gene (Bcl-2), cytochrome C (Cyt-C), and aspartate proteolytic enzyme-3 (caspase-3) were examined by immunofluorescence. Finally, in vivo, hematoxylin and eosin (H&E) staining was used to observe the pathological changes in hepatocellular carcinoma samples. Western blots and immunohistochemistry were used to detect the anticancer properties of HXHJ ointment. The results in vitro showed that 20% HXHJ Ointment serum could significantly inhibit HepG2 cell proliferation, increased tumor suppressor gene p53, downregulated antiapoptotic protein Bcl-2, promoted the release of mitochondrial Cyt-C, activated caspase-3, and induced HepG2 cell apoptosis. Furthermore, in vivo experiments showed that HXHJ Ointment could effectively inhibit tumor growth in nude mice xenotransplanted with HepG2 cells, changed the morphology of tumor cells, and regulated the expression of apoptosis-related protein pathway p53/Bcl-2/Cyt-C/caspase-3. HXHJ Ointment can significantly inhibit the development of hepatocellular carcinoma, and its mechanism may be related to the regulation of p53/Bcl-2/Cyt-C/caspase-3 signaling pathway to induce cell mitochondrial apoptosis.