Hypoxia-induced miR-5100 promotes exosome-mediated activation of cancer-associated fibroblasts and metastasis of head and neck squamous cell carcinoma.

The invasion-metastasis cascade in head and neck squamous cell carcinoma (HNSCC) is predominantly caused by the interaction between tumor cells and tumor microenvironment, including hypoxia as well as stromal cells. However, the mechanism of hypoxia-activated tumor-stroma crosstalk in HNSCC metastasis remains to be deciphered. Here, we demonstrated that HIF1α was upregulated in HNSCC specimens compared with adjacent normal tissues, whose overexpression was associated with lymph node metastasis and predicted unfavorable prognosis. HIF1α expression correlated positively with the levels of miR-5100 as well as α-SMA, the marker of CAFs. Hypoxia/HIF1α regulated transcriptionally miR-5100 to promote the degradation of its target gene QKI, which acts as a tumor suppressor in HNSCC. Hypoxic HNSCC-derived exosomal miR-5100 promoted the activation of CAFs by orchestrating QKI/AKT/STAT3 axis, which further facilitated HNSCC metastasis. Additionally, miR-5100 derived from plasma exosomes indicated HNSCC malignant progression. In conclusion, our findings illuminate a novel HIF1α/miR-5100/QKI pathway in HNSCC metastasis, and suggest that miR-5100 might be a potential biomarker and therapeutic target for HNSCC.

Hypoxic tumor-derived exosomal miR-21 induces cancer-associated fibroblast activation to promote head and neck squamous cell carcinoma metastasis.

BACKGROUND: Both microRNA-21-5p (miR-21) and the tumor microenvironment, including hypoxia and cancer-associated fibroblasts (CAFs), play a vital role in head and neck squamous cell carcinoma (HNSCC), but whether there is an interaction and the specific regulatory mechanism between them in the process of metastasis is still unclear. In this study, we aimed to elucidate the connection and regulatory mechanism of miR-21, hypoxia, and CAFs in HNSCC metastasis. METHODS: The underlying mechanisms of hypoxia inducible factor 1 subunit alpha (HIF1α) regulating miR-21 transcription, promoting exosome secretion, CAFs activation, tumor invasion, and lymph node metastasis were determined through quantitative real-time PCR, immunoblotting, transwell, wound healing, immunofluorescence, ChIP, electron microscopy, nanoparticle tracking analysis, dual-luciferase reporter assay, co-culture model and xenografts experiments. RESULTS: MiR-21 promoted the invasion and metastasis of HNSCC in vitro and in vivo, whereas HIF1α knockdown inhibited these processes. HIF1α upregulated transcription of miR-21 and promoted the release of exosomes from HNSCC cells. Exosomes derived from hypoxic tumor cells were rich in miR-21, which induced NFs activation towards CAFs by targeting YOD1. Knockdown the expression level of miR-21 in CAFs prevented lymph node metastasis in HNSCC. CONCLUSION: Hypoxic tumor cell-derived exosomal miR-21 might be a therapeutic target to prevent or delay HNSCC invasion and metastasis.

LncRNA MALAT1 promotes growth and metastasis of head and neck squamous cell carcinoma by repressing VHL through a non-canonical function of EZH2.

Long non-coding RNAs (LncRNAs) are implicated in malignant progression of human cancers. Metastasis-associated lung adenocarcinoma transcript 1 (MALAT1), a well-known lncRNA, has been reported to play crucial roles in multiple malignancies including head and neck squamous cell carcinoma (HNSCC). However, the underlying mechanisms of MALAT1 in HNSCC progression remain to be further investigated. Here, we elucidated that compared with normal squamous epithelium, MALAT1 was notably upregulated in HNSCC tissues, especially in which was poorly differentiated or with lymph nodes metastasis. Moreover, elevated MALAT1 predicted unfavorable prognosis of HNSCC patients. The results of in vitro and in vivo assays showed that targeting MALAT1 could significantly weaken the capacities of proliferation and metastasis in HNSCC. Mechanistically, MALAT1 inhibited von Hippel-Lindau tumor suppressor (VHL) by activating EZH2/STAT3/Akt axis, then promoted the stabilization and activation of ß-catenin and NF-κB which could play crucial roles in HNSCC growth and metastasis. In conclusion, our findings reveal a novel mechanism for malignant progression of HNSCC and suggest that MALAT1 might be a promising therapeutic target for HNSCC treatment.

Detection of thyroglobulin in fine-needle aspiration for diagnosis of metastatic lateral cervical lymph nodes in papillary thyroid carcinoma: A retrospective study.

Objective: We analysed the diagnostic performance of thyroglobulin in fine-needle aspiration (FNA-Tg) in the suspicious lateral cervical lymph nodes (CLNs) in patients with papillary thyroid cancer (PTC), proposed the best cutoff value and discussed the factors that may affect the diagnostic value of FNA-Tg. Methods: In the present study, a retrospective analysis of 403 patients with PTC with 448 suspected lateral CLNs metastasis from October 2019 to May 2021 was performed. The cutoff value according to the receiver operating characteristic (ROC) curve was determined, and the Wilcoxon rank-sum test was used to evaluate the correlation between FNA-Tg and factors. Results: According to the ROC curve, the cutoff value of FNA-Tg was 3.69 ng/ml (sensitivity, 92.48%; specificity, 75.00%). Patients who underwent total thyroidectomy were excluded. Compared with US and FNAC, the diagnostic performance of FNA-Tg was the greatest, especially for small CLNs (diameter ≤ 1 cm), cystic CLNs, and patients with Hashimoto's thyroiditis (HT). Moreover, FNA-Tg levels were correlated with the presence of HT (p = 0.003), the anti-thyroglobulin antibody (Tg-Ab) (p < 0.001), the ratio of metastatic lateral CLNs (p = 0.004) and Tg assay kits (p < 0.001). Conclusions: FNA-Tg measurement is sensitive enough for diagnosing lateral CLN metastases from PTC, but its diagnostic value is compromised by a number of factors.

The diagnostic value of thyroglobulin in fine-needle aspiration of metastatic lymph nodes in patients with papillary thyroid cancer and its influential factors.

Thyroglobulin (Tg) measurement in fine-needle aspiration (FNA-Tg) has proved to be an excellent tool to identify metastatic cervical lymph nodes (CLN) before or after surgery for papillary thyroid cancer (PTC). The diagnostic value of FNA-Tg for metastatic CLN in PTC patients is higher than that of ultrasound (US) and fine-needle aspiration cytology (FNAC), especially for small or cystic LN. The combination of FNAC and FNA-Tg can provide nearly 100% diagnostic sensitivity and specificity for CLN metastasis. However, the cutoff values of FNA-Tg for metastatic CLN have not been standardized, and the reported cutoff values of FNA-Tg range from 0.2 ng/ml to 77 ng/ml because of the differences in study samples, Tg measurement methods, Tg assays kits, etc. Serum anti-thyroglobulin antibody level, serum thyroglobulin level, the presence or absence of thyroid glands, and the characteristics of CLN may be factors affecting the accuracy of FNA-Tg. This review summarizes the recent research on the application of FNA-Tg in the diagnosis of metastatic LN in PTC and provides a reliable basis for the clinical diagnosis of cervical lymph node metastasis.

JOSD1 promotes proliferation and chemoresistance of head and neck squamous cell carcinoma under the epigenetic regulation of BRD4.

BACKGROUND: Deubiquitinating enzymes (DUBs) play critical roles in various cancers by modulating functional proteins post-translationally. Previous studies have demonstrated that DUB Josephin Domain Containing 1 (JOSD1) is implicated in tumor progression, however, the role and mechanism of JOSD1 in head and neck squamous cell carcinoma (HNSCC) remain to be explored. In this study, we aimed to identify the clinical significance and function of JOSD1 in HNSCC. METHODS: The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) databases were analyzed to find novel DUBs in HNSCC. Immunohistochemistry assay was performed to determine the expression of JOSD1 in our cohort of 42 patients suffered with HNSCC. Kaplan-Meier analysis was used to identify the correlation between JOSD1 and the prognosis of HNSCC patients. The regulation of BRD4 on JOSD1 was determined by using pharmacological inhibition and gene depletion. The in vitro and in vivo experiments were conducted to elucidate the role of JOSD1 in HNSCC. RESULTS: The results of IHC showed that JOSD1 was aberrantly expressed in HNSCC specimens, especially in the chemoresistant ones. The overexpression of JOSD1 indicated poor clinical outcome of HNSCC patients. Moreover, JOSD1 depletion dramatically impaired cell proliferation and colony formation, and promoted cisplatin-induced apoptosis of HNSCC cells in vitro. Additionally, JOSD1 suppression inhibited the tumor growth and improved chemosensitivity in vivo. The epigenetic regulator BRD4 contributed to the upregulation of JOSD1 in HNSCC. CONCLUSIONS: These results demonstrate that JOSD1 functions as an oncogene in HNSCC progression, and provide a promising target for clinical diagnosis and therapy of HNSCC.

The PSMD14 inhibitor Thiolutin as a novel therapeutic approach for esophageal squamous cell carcinoma through facilitating SNAIL degradation.

Metastasis and chemoresistance are major causes of poor prognosis in patients with esophageal squamous cell carcinoma (ESCC), manipulated by multiple factors including deubiquitinating enzyme (DUB). DUB PSMD14 is reported to be a promising therapeutic target in various cancers. Here, we explored the antitumor activity of Thiolutin (THL), the PSMD14 inhibitor, as a new therapy strategy in ESCC. Methods: Through 4-NQO-induced murine ESCC model, we investigated the expression of PSMD14 in esophageal tumorigenesis. Ubiquitin-AMC assay was performed to evaluate DUB activity of PSMD14 with THL treatment. The effect of THL on epithelial-to-mesenchymal transition (EMT), invasion, stemness and chemosensitivity was detected by using in vitro and in vivo experiments. Immunoprecipitation and in vivo ubiquitination assay were conducted to examine whether THL could impair the deubiquitination and stability of SNAIL regulated by PSMD14. Results: Compared with normal esophageal epithelium, PSMD14 was upregulated in 4-NQO-induced murine esophageal epithelium dysplasia and ESCC tissues. THL could significantly weaken DUB activity of PSMD14. Furthermore, the results of in vitro and in vivo assays showed that THL efficiently suppressed motility and stemness and increased sensitivity to cisplatin in ESCC. Mechanically, THL impaired the interaction between PSMD14 and SNAIL, then promoted the ubiquitination and degradation of SNAIL to inhibit EMT which plays a crucial role in ESCC metastasis, stemness and chemosensitivity. TCGA database analysis revealed that high concomitant PSMD14/SNAIL expression predicted shorter overall survival in esophageal cancer. Conclusion: Our findings demonstrate for the first time that suppression of PSMD14/SNAIL axis by THL could be a novel and promising therapeutic approach for ESCC clinical therapy.

Blockade of deubiquitinating enzyme PSMD14 overcomes chemoresistance in head and neck squamous cell carcinoma by antagonizing E2F1/Akt/SOX2-mediated stemness.

Increasing evidence reveals a close relationship between deubiquitinating enzymes (DUBs) and cancer progression. In this study, we attempted to identify the roles and mechanisms of critical DUBs in head and neck squamous cell carcinoma (HNSCC). Methods: Bioinformatics analysis was performed to screen differentially expressed novel DUBs in HNSCC. Immunohistochemistry assay was used to measure the expression of DUB PSMD14 in HNSCC specimens and adjacent normal tissues. The level of PSMD14 in HNSCC tumorigenesis was investigated using a 4-NQO-induced murine HNSCC model. The function of PSMD14 was determined through loss-of-function assays. Chromatin immunoprecipitation, immunoprecipitation and in vivo ubiquitination assay were conducted to explore the potential mechanism of PSMD14. The anti-tumor activity of PSMD14 inhibitor Thiolutin was assessed by in vitro and in vivo experiments. Results: We identified PSMD14 as one of significantly upregulated DUBs in HNSCC tissues. Aberrant expression of PSMD14 was associated with tumorigenesis and malignant progression of HNSCC and further indicated poor prognosis. The results of in vitro and in vivo experiments demonstrated PSMD14 depletion significantly undermined HNSCC growth, chemoresistance and stemness. Mechanically, PSMD14 inhibited the ubiquitination and degradation of E2F1 to improve the activation of Akt pathway and the transcription of SOX2. Furthermore, PSMD14 inhibitor Thiolutin exhibited a potent anti-tumor effect on HNSCC in vivo and in vitro by impairing DUB activity of PSMD14. Conclusion: Our findings demonstrate the role and mechanism of PSMD14 in HNSCC, and provide a novel and promising target for diagnosis and clinical therapy of HNSCC.