Expression and function of NET-1 in human skin squamous cell carcinoma

TSPAN1: A Novel Protein Involved in Head and Neck Squamous Cell Carcinoma Chemoresistance

Simple Summary

Therapy resistance in head and neck squamous cell carcinoma (HNSCC) patients is the main obstacle to achieve more effective treatments that improve survival and quality of life of these patients. Therefore, it is of vital importance to unravel the molecular and cellular mechanisms by which tumor cells acquire resistance to chemotherapy. We conducted a comparative proteomic study involving cisplatin-resistant cells and cancer stem cells with the aim of identifying proteins potentially implicated in the acquisition of cisplatin resistance. Through this study, we identified for the first time tetraspanin-1 (TSPAN1) as an important protein involved in the development, progression and chemoresistance of HNSCC tumors.

Abstract

Sensitization of resistant cells and cancer stem cells (CSCs) represents a major challenge in cancer therapy. A proteomic study revealed tetraspanin-1 (TSPAN1) as a protein involved in acquisition of cisplatin (CDDP) resistance (Data are available via ProteomeXchange with identifier PXD020159). TSPAN1 was found to increase in CDDP-resistant cells, CSCs and biopsies from head and neck squamous cell carcinoma (HNSCC) patients. TSPAN1 depletion in parental and CDDP-resistant HNSCC cells reduced cell proliferation, induced apoptosis, decreased autophagy, sensitized to chemotherapeutic agents and inhibited several signaling cascades, with phospho-SRC inhibition being a major common target. Moreover, TSPAN1 depletion in vivo decreased the size and proliferation of parental and CDDP-resistant tumors and reduced metastatic spreading. Notably, CDDP-resistant tumors showed epithelial–mesenchymal transition (EMT) features that disappeared upon TSPAN1 inhibition, suggesting a link of TSPAN1 with EMT and metastasis. Immunohistochemical analysis of HNSCC specimens further revealed that TSPAN1 expression was correlated with phospho-SRC (pSRC), and inversely with E-cadherin, thus reinforcing TSPAN1 association with EMT. Overall, TSPAN1 emerges as a novel oncogenic protein and a promising target for HNSCC therapy.

Evaluation of therapeutic effect of targeting nanobubbles conjugated with NET-1 siRNA by shear wave elastography: an in vivo study of hepatocellular carcinoma bearing mice model

This study aimed at investigating the tumor stiffness of hepatocellular carcinoma (HCC) bearing mice model in vivo to evaluate the therapeutic efficacy of targeting nanobubbles (TNBS) conjugated with NET-1 siRNA (NET-1 siRNA-TNBS). Also tested whether shear wave elastography (SWE) could demonstrate the pathological tumor changes and used to monitor therapeutic efficacy as a noninvasive method. The HCC bearing mice model was established by injecting human HCC cell line (HepG2). The mice were then divided into three groups randomly, and were treated with TNBS conjugated with NET-1 siRNA, TNBS conjugated with negative control gene, and saline as control. US-SWE was performed for three times. SWE values of all the tumors in three groups were increased with tumor growth. Emax was correlated with tumor size (p < .05). NET-1 gene (treatment group) significantly delayed the growth of tumor size compared to other two groups (p < .0001), showing a significantly increased Emax (p < .05). Immunohistochemical results showed that the NET-1 protein expression was significantly lower than the negative control and blank groups. In conclusion, TNBS conjugated with NET-1 siRNA inhibited tumor growth and prolonged the life of experimental animals. SWE provided a noninvasive and real time imaging method to detect the changes in tumor development.

miRNAs: A Promising Target in the Chemoresistance of Bladder Cancer

Chemotherapy is an important cancer treatment method. Tumor chemotherapy resistance is one of the main factors leading to tumor progression. Like other malignancies, bladder cancer, especially muscle-invasive bladder cancer, is prone to chemotherapy resistance. Additionally, only approximately 50% of muscle-invasive bladder cancer responds to cisplatin-based chemotherapy. miRNAs are a class of small, endogenous, noncoding RNAs that regulate gene expression at the posttranscriptional level, which results in the inhibition of translation or the degradation of mRNA. In the study of miRNAs and cancer, including gastric cancer, prostate cancer, liver cancer, and colorectal cancer, it has been found that miRNAs can regulate the expression of genes related to tumor resistance, thereby promoting the progression of tumors. In bladder cancer, miRNAs are also closely related to chemotherapy resistance, suggesting that miRNAs can be a new therapeutic target for the chemotherapy resistance of bladder cancer. Therefore, understanding the mechanisms of miRNAs in the chemotherapy resistance of bladder cancer is an important foundation for restoring the chemotherapy sensitivity of bladder cancer and improving the efficacy of chemotherapy and patient survival. In this article, we review the role of miRNAs in the development of chemotherapy-resistant bladder cancer and the various resistance mechanisms that involve apoptosis, the cell cycle, epithelial-mesenchymal transition (EMT), and cancer stem cells (CSCs).

Expression and function of tetraspanin 1 in esophageal carcinoma

The present study explored the expression of tetraspanin 1 (TSPAN1) in esophageal carcinoma (EC) and its association with clinicopathological factors. TSPAN1 small interfering RNA (siRNA) was designed to target the TSPAN1 gene in Eca-109 cells in order to explore the biological function of TSPAN1 in the proliferation and apoptosis of EC. The results demonstrated that the level of TSPAN1 expression in EC tissue was significantly increased compared with that in adjacent normal tissue (P<0.001). TSPAN1 expression was also associated with histological differentiation, depth of invasion, lymph node metastasis (all P<0.05) and Ki-67 (P<0.01). However, no association was observed between TSPAN expression and gender, age or location (P>0.05). In addition, silencing TSPAN1 markedly inhibited proliferation while increasing the apoptosis rate of Eca-109 cells, which was demonstrated by detecting the expression of the cell proliferation-associated gene Ki-67 and the apoptotic gene caspase-3 (P<0.05). Taken together, these results indicated that TSPAN1 functions as a tumor-associated gene in EC through promoting cell proliferation and suppressing apoptosis, and siRNA technology may provide an advanced alternative in the development of therapeutics for EC.

Prognostic significance of Tspan9 in gastric cancer

Tetraspanins are a large superfamily of glycoproteins, which are engaged in a wide range of specific molecular interactions by forming tetraspanin-enriched microdomains. Tetraspanin 9 (Tspan9) is a previously poorly studied tetraspanin gene, which was predominantly identified as an amplified gene in serous Fallopian tube carcinoma. However, the expression and role of Tspan9 in gastric cancer have yet to be fully elucidated. The aim of the present study was to evaluate the expression and clinical significance of Tspan9 in gastric cancer. In the present study, 105 gastric cancer tissue samples and corresponding adjacent normal samples were detected for Tspan9 expression using immunohistochemistry; furthermore, the association between clinical characteristics and Tspan9 expression was also analyzed. Tspan9 expression was determined to be significantly lower in cancer samples compared with those in corresponding adjacent normal samples (P<0.001). However, its increased levels of expression in cancer samples appeared to demonstrate a poorer prognostic tendency, which is associated with deeper tumor depth (P=0.025), more nodal involvement (P=0.01), more advanced tumor/lymph node/metastasis (TNM) stages (P=0.017) and a larger tumor size (P=0.026). Additionally, multivariate analysis demonstrated that high expression of Tspan9 was an independent prognostic factor for poor overall survival (P<0.01). These results suggested that Tspan9 may be used as a potential prognostic factor in gastric cancer.

Multi-target siRNA: Therapeutic Strategy for Hepatocellular Carcinoma

Multiple targets RNAi strategy is a preferred way to treat multigenic diseases, especially cancers. In the study, multi-target siRNAs were designed to inhibit NET-1, EMS1 and VEGF genes in hepatocellular carcinoma (HCC) cells. And multi-target siRNAs showed better silencing effects on NET-1, EMS1 and VEGF, compared with single target siRNA. Moreover, multi-target siRNA showed greater suppression effects on proliferation, migration, invasion, angiogenesis and induced apoptosis in HCC cells. The results suggested that multi-target siRNA might be a preferred strategy for cancer therapy and NET-1, EMS1 and VEGF could be effective targets for HCC treatments.

Neuroepithelial transforming gene 1 functions as a potential prognostic marker for patients with non-small cell lung cancer

Non-small cell lung cancer (NSCLC) is the most common histological cancer sub‑type worldwide. Neuroepithelial transforming gene 1 (Net-1), a Ras homolog family member A-specific guanine nucleotide exchange factor, has been shown to be upregulated in several human cancer types. However, the clinical significance of Net‑1 expression in NSCLC has remained elusive. The present study assessed Net‑1 mRNA and protein levels by reverse-transcription quantitative polymerase chain reaction and western blot analysis of 64 cases of NSCLC as well as their adjacent normal tissues. Furthermore, Net‑1 protein expression in tumor tissues derived from clinically annotated NSCLC cases at stages I‑III was detected by immunohistochemical staining. The results showed that Net‑1 mRNA and protein levels in NSCLC tissues were significantly elevated compared with those in their corresponding non‑tumor tissues. In addition, Net‑1 expression was strongly associated with the patients' pathological characteristics, including clinical stage, lymph node metastasis, distant metastasis and differentiation degree (P<0.05). In conclusion, the results of the present study suggested that Net‑1 expression has a significant role in the tumorigenesis of distinct histotypes and sub‑types of NSCLC, and may therefore be utilized as a biomarker as well as an important therapeutic target in NSCLC.