F806 Suppresses the Invasion and Metastasis of Esophageal Squamous Cell Carcinoma via Downregulating F-Actin Assembly-Related Rho Family Proteins

Inhibition of p62 and/or NFE2L2 induced autophagy impaires esophageal squamous cell cancer metastasis by reversing EMT

Esophageal squamous cell carcinoma (ESCC) pathogenesis is influenced by both NFE2L2 (nuclear factor erythroid 2-related factor 2) and SQSTM1 (sequestosome 1), also known as p62. However, while there is evidence that these two proteins can interact with one another in a range of pathological contexts, whether these interactions govern the development or progression of ESCC remains unknown. In the present study, analyses of the GEPIA database revealed the simultaneous upregulation of both NFE2L2 and p62 in ESCC, as was further confirmed through biochemical analyses conducted with a human tumor microarray. Knocking down the expression of one or both of these factors demonstrated that both p62 and NFE2L2 mediate the progression of ESCC, as such downregulation altered the morphological characteristics of these cells and suppressed the epithelial-mesenchymal transition (EMT). Strikingly, these experiments revealed synergistic interactions between NFE2L2 and p62 in the promotion of ESCC invasivity and EMT induction. The treatment of cells with the autophagy inhibitors 3-MA, however, was sufficient to partially reverse the anti-metastatic effects of knocking down p62 and/or NFE2L2. Together, these data illustrate the ability of p62 and NFE2L2 to function in a synergistic manner, promoting ESCC cell metastatic progression and EMT induction through mechanisms linked to autophagic activity. As such, efforts to simultaneously target both of these proteins may represent a viable means of providing new treatment options to ESCC patients.

Targeting USP10 induces degradation of oncogenic ANLN in esophageal squamous cell carcinoma

Anillin (ANLN) is a mitosis-related protein that promotes contractile ring formation and cytokinesis, but its cell cycle-dependent degradation mechanisms in cancer cells remain unclear. Here, we show that high expression of ANLN promotes cytokinesis and proliferation in esophageal squamous cell carcinoma (ESCC) cells and is associated with poor prognosis in ESCC patients. Furthermore, the findings of the study showed that the deubiquitinating enzyme USP10 interacts with ANLN and positively regulates ANLN protein levels. USP10 removes the K11- and K63-linked ubiquitin chains of ANLN through its deubiquitinase activity and prevents ANLN ubiquitin-mediated degradation. Importantly, USP10 promotes contractile ring assembly at the cytokinetic furrow as well as cytokinesis by stabilizing ANLN. Interestingly, USP10 and the E3 ubiquitin ligase APC/C co-activator Cdh1 formed a functional complex with ANLN in a non-competitive manner to balance ANLN protein levels. In addition, the macrolide compound FW-04-806 (F806), a natural compound with potential for treating ESCC, inhibited the mitosis of ESCC cells by targeting USP10 and promoting ANLN degradation. F806 selectively targeted USP10 and inhibited its catalytic activity but did not affect the binding of Cdh1 to ANLN and alters the balance of the USP10-Cdh1-ANLN complex. Additionally, USP10 expression was positively correlated with ANLN level and poor prognosis of ESCC patients. Overall, targeting the USP10-ANLN axis can effectively inhibit ESCC cell-cycle progression.

Anti-tumour effects of a macrolide analog F806 in oesophageal squamous cell carcinoma cells by targeting and promoting GLUT1 autolysosomal degradation

Cancer cells are characterized by altered energetic metabolism with increasing glucose uptake. F806, a 16-membered macrodiolide analogue, has anti-tumour effects on oesophageal squamous cell carcinoma (ESCC) cells. However, its precise anti-tumour mechanism remains unclear. Here, metascape analysis of our previous quantitative proteomics data showed that F806 induced glucose starvation response and inhibited energy production in ESCC cells. The reduced glucose uptake and ATP production were further validated by the fluorescent methods, using glucose-conjugated bioprobe Glu-1-O-DCSN, and the bioluminescent methods, respectively. Consistently, under F806 treatment the AMP-activated protein kinase signalling was activated, and autophagy flux was promoted and more autophagosomes were formed. Moreover, live-cell imaging and immunofluorescence analysis showed that F806 induced GLUT1 plasma membrane dissociation and promoted its internalization and autolysosome accumulation and lysosome degradation. Furthermore, molecular docking studies demonstrated that F806 bound to GLUT1 with a comparable binding energy to that of GLUT1's direct interacting inhibitor cytochalasin B. Amino acid mutation was used to test which residues of GLUT1 may participate in F806 mediated-GLUT1 internalization and degradation, and results showed that Thr137, Asn411 and Trp388 were required for GLUT1 internalization and degradation, respectively. Taken together, these findings shed light on a novel anti-tumour mechanism of F806 by targeting and promoting GLUT1 internalization and further autolysosomal degradation.

Low anti-CFL1 antibody with high anti-ACTB antibody is a poor prognostic factor in esophageal squamous cell carcinoma

BACKGROUND

Cofilin (CFL1, actin-binding protein) and β-actin (ACTB) are key molecules in the polymerization and depolymerization of actin microfilaments. The levels of these antibodies were analyzed, and the clinicopathological significance in patients with esophageal carcinoma were evaluated.

METHODS

The levels of anti-CFL1 and anti-ACTB antibodies were analyzed in serum samples of patients with esophageal carcinoma and of healthy donors. Eighty-seven cases underwent radical surgery and the clinicopathological characteristics and prognosis was examined.

RESULTS

Serum anti-CFL1 antibody (s-CFL1-Ab) levels and anti-ACTB antibody (s-ACTB-Ab) levels were significantly higher in patients with esophageal carcinoma than in healthy donors. Following the receiver operating characteristic curve analysis between healthy donors and esophageal carcinoma, the sensitivity and specificity for serum anti-CFL1 antibody (s-CFL1-Ab) were 53.3% and 68.8%. The sensitivity and specificity for serum anti-ACTB antibody (s-ACTB-Ab) were 54.9% and 67.7%, respectively. Univariate and multivariate analysis showed that s-CFL1-Ab and s-ACTB-Ab levels were not associated with sex, age, tumor depth, lymph node metastasis, or anti-p53-antibody levels. s-ACTB-Ab levels but not s-CFL1-Ab levels significantly correlated with squamous cell carcinoma antigen. Neither s-CFL1-Ab nor s-ACTB-Ab levels alone were obviously related to overall survival. However, patients with low s-CFL1-Ab levels and high s-ACTB-Ab levels exhibited significantly more unfavorable prognoses than those with high s-CFL1-Ab and low s-ACTB-Ab levels.

CONCLUSIONS

Serum levels of anti-CFL1 and anti-ACTB antibodies were significantly higher in patients with esophageal carcinoma than in healthy donors. A combination of low anti-CFL1 and high anti-ACTB antibodies is a poor prognostic factor in esophageal carcinoma.

Actin-Binding Proteins as Potential Biomarkers for Chronic Inflammation-Induced Cancer Diagnosis and Therapy

Actin-binding proteins (ABPs), by interacting with actin, regulate the polymerization, depolymerization, bundling, and cross-linking of actin filaments, directly or indirectly, thereby mediating the maintenance of cell morphology, cell movement, and many other biological functions. Consequently, these functions of ABPs help regulate cancer cell invasion and metastasis when cancer occurs. In recent years, a variety of ABPs have been found to be abnormally expressed in various cancers, indicating that the detection and interventions of unusual ABP expression to alter this are available for the treatment of cancer. The early stages of most cancer development involve long-term chronic inflammation or repeated stimulation. This is the case for breast cancer, gastric cancer, lung cancer, prostate cancer, liver cancer, esophageal cancer, pancreatic cancer, melanoma, and colorectal cancer. This article discusses the relationship between chronic inflammation and the above-mentioned cancers, emphatically introduces relevant research on the abnormal expression of ABPs in chronic inflammatory diseases, and reviews research on the expression of different ABPs in the above-mentioned cancers. Furthermore, there is a close relationship between ABP-induced inflammation and cancer. In simple terms, abnormal expression of ABPs contributes to the chronic inflammation developing into cancer. Finally, we provide our viewpoint regarding these unusual ABPs serving as potential biomarkers for chronic inflammation-induced cancer diagnosis and therapy, and interventions to reverse the abnormal expression of ABPs represent a potential approach to preventing or treating the corresponding cancers.

Rho GTPases: Promising candidates for overcoming chemotherapeutic resistance

Despite therapeutic advances, resistance to chemotherapy remains a major challenge to patients with malignancies. Rho GTPases are essential for the development and progression of various diseases including cancer, and a vast number of studies have linked Rho GTPases to chemoresistance. Therefore, understanding the underlying mechanisms can expound the effects of Rho GTPases towards chemotherapeutic agents, and targeting Rho GTPases is a promising strategy to downregulate the chemo-protective pathways and overcome chemoresistance. Importantly, exceptions in certain biological conditions and interactions among the members of Rho GTPases should be noted. In this review, we focus on the role of Rho GTPases, particularly Rac1, in regulating chemoresistance and provide an overview of their related mechanisms and available inhibitors, which may offer novel options for future targeted cancer therapy.

NR4A1 promotes TNF‑α‑induced chondrocyte death and migration injury via activating the AMPK/Drp1/mitochondrial fission pathway

Nuclear receptor subfamily 4 group A member 1 (NR4A1)-induced chondrocyte death plays a critical role in the development of osteoarthritis through poorly defined mechanisms. The present study aimed to investigate the role of NR4A1 in regulating chondrocyte death in response to tumor necrosis factor-α (TNF-α) and cycloheximide (CHX) treatment, with a focus on mitochondrial fission and the AMP-activated protein kinase (AMPK) signaling pathway. The results demonstrated that NR4A1 was significantly upregulated in TNF-α and CHX exposed chondrocytes. Increased NR4A1 triggered mitochondrial fission via the AMPK/dynamin-related protein 1 (Drp1) pathway, resulting in mitochondrial dysfunction, and mitochondrial permeability transition pore (mPTP) opening-related cell death. Furthermore, excessive mitochondrial fission impaired chondrocyte migration through imbalance of F-actin homeo-stasis. Inhibiting NR4A1 attenuated TNF-α and CHX-induced mitochondrial fission and, thus, reduced mitochondrial dysfunction in chondrocytes, mPTP opening-related cell death and migration injury. Altogether, the present data confirmed that mitochondrial fission was involved in NR4A1-mediated chondrocyte injury via regulation of mitochondrial dysfunction, mPTP opening-induced cell death and F-actin-related migratory inhibition.