DCBLD2 Mediates Epithelial-Mesenchymal Transition-Induced Metastasis by Cisplatin in Lung Adenocarcinoma

TMEM205 induces TAM/M2 polarization to promote cisplatin resistance in gastric cancer

Cisplatin (DDP) is a basic chemotherapy drug for gastric cancer (GC). With the increase of DDP drug concentration in clinical treatment, cancer cells gradually became resistant. Therefore, it is necessary to find effective therapeutic targets to enhance the sensitivity of GC to DDP. Studies have shown that Transmembrane protein 205 (TMEM205) is overexpressed in DDP-resistant human epidermoid carcinoma cells and correlates with drug resistance, and database analyses show that TMEM 205 is also overexpressed in GC, but its role in cisplatin-resistant gastric cancer remains unclear. In this study, we chose a variety of experiments in vivo and vitro, aiming to investigate the role of TMEM 205 in cisplatin resistance in gastric cancer. The results showed that TMEM 205 promoted proliferation, stemness, epithelial-mesenchymal transition (EMT), migration and angiogenesis of gastric cancer cells through activation of the Wnt/β-catenin signaling pathway. In addition, TMEM205 promotes GC progression by inducing M2 polarization of tumor-associated macrophages (TAMs). These results suggest that TMEM205 may be an effective target to regulate the sensitivity of GC to DDP, providing a new therapeutic direction for clinical treatment.

Development of a prognostic model for lung adenocarcinoma polarity-related genes and analysis of immune landscape

Despite the progress made in the management of lung adenocarcinoma (LUAD), the overall prognosis for LUAD individuals remains suboptimal. While the role of cell polarity in tumor invasion and metastasis is well established, its prognostic significance in LUAD is still unknown. Differential analysis was performed on the Cancer Genome Atlas (TCGA)-LUAD and normal lung tissue, and candidate genes were identified by intersecting differentially expressed genes with polarity-related genes (PRGs). A prognostic model was constructed using univariate and multivariate Cox regression and LASSO regression. To enhance the robustness of the analysis, an independent prognostic analysis was conducted by incorporating relevant clinical information. The accuracy and sensitivity of the model were validated using survival analysis and ROC curves. Finally, immune landscape, immune therapy, tumor mutation burden, and drug sensitivity analysis were carried out on high- and low-risk patients. Ten prognostic genes were screened to divide LUAD patients into different risk groups. Survival analysis, ROC curves, and univariate/multivariate Cox regression analyses collectively demonstrated the favorable predictive performance of the model, which could be an independent prognostic factor. The nomogram, in conjunction with the calibration curve, demonstrated the model's compelling predictive capacity in prognosticating the overall survival of LUAD individuals. Low-risk LUAD patients exhibited heightened levels of immune cell infiltration, immune scores, and immune checkpoint expression compared to high-risk individuals. So, they may have a greater likelihood of benefiting from immune therapy. The high-risk group demonstrated a remarkably higher tumor mutation burden (TMB) in contrast with the low-risk group. XAV-939, Fulvestrant, and SR16157 may have potential value in the clinical use of LUAD. We revealed the potential linkage between PRGs and LUAD prognosis, and the application of these prognostic factors in risk stratification and prognosis prediction of LUAD patients may be of great significance.

Biomarker Analysis from a Phase I/Ib Study of Regorafenib and Nivolumab in Mismatch Repair-Proficient Advanced Refractory Colorectal Cancer

Previously, we reported the modest but durable anticancer activity of regorafenib/nivolumab in mismatch repair-proficient (pMMR) refractory colorectal cancer in our I/Ib study. Our finding suggests the necessity of biomarkers for better selection of patients. Baseline clinical and pathological characteristics, blood and tumor samples from the patients in the trial were collected and evaluated to discover potential biomarkers. The obtained samples were assessed for immunohistochemistry, ELISA and RNA sequencing. Their correlations with clinical outcome were analyzed. A high albumin level was significantly associated with improved progression-free survival (PFS), overall survival (OS) and disease control. Non-liver metastatic disease showed prolonged PFS and OS. Low regulatory T-cell (Treg) infiltration correlated with prolonged PFS. Low MIP-1β was associated with durable response and improved OS significantly. Upregulation of 23 genes, including CAPN9, NAPSA and ROS1, was observed in the durable disease control group, and upregulation of 10 genes, including MRPS18A, MAIP1 and CMTR2, was associated with a statistically significant improvement of PFS. This study suggests that pretreatment albumin, MIP-1β, non-liver metastatic disease and Treg infiltration may be potential predictive biomarkers of regorafenib/nivolumab in pMMR colorectal cancer. Further studies are needed to confirm these findings.

SB431542 partially inhibits high glucose-induced EMT by restoring mitochondrial homeostasis in RPE cells

BACKGROUND

The epithelial-mesenchymal transition (EMT) of retinal pigment epithelial (RPE) cells participated in the development of retinal fibrosis. SB431542 is a small molecule inhibitor with inhibitory effects on the ALK4, ALK5 and ALK7. Our study aimed to explore the effect of SB431542 on the EMT of RPE cells and to provide new ideas for the treatment of retinal fibrosis.

METHODS

We performed fundus fluorescein angiography, optical coherence tomography and hematoxylin-eosin staining in vivo to observe the effect of SB431542 on choroidal neovascularization (CNV)-induced retinopathy. The proliferation, migration, cytoskeleton, adhesion, reactive oxygen species (ROS), mitochondrial morphology and membrane potential of RPE cells were observed in vitro through fluorescein diacetate staining, Cell Counting Kit-8 experiment, wound healing assay, phalloidin staining, immunofluorescence, MitoSOX, DCFH-DA, MitoTracker and JC-10 staining. Western blot, reverse transcription quantitative and immunofluorescence were used to detect the expression of EMT-related markers, pERK1/2, pGSK3β and β-catenin.

RESULTS

SB431542 significantly alleviated retinopathy in the CNV model. The proliferation, migration and adhesion in RPE cells decreased to a certain extent in SB431542 treatment. SB431542 partially normalized the structure of RPE cells. The expression levels of E-cadherin increased, while the expression levels of laminin and N-cadherin decreased with SB431542 treatment. SB431542 reduced the production of total ROS, mitochondrial SOX and recovered the mitochondrial membrane potential to a certain degree. In addition, our study showed that SB431542 downregulated the phosphorylation of ERK1/2, GSK3β and the expression of β-catenin.

CONCLUSION

SB431542 improved EMT in RPE cells by maintaining mitochondrial homeostasis via the ERK1/2 and GSK3β/β-catenin pathways. Video Abstract SB431542 inhibits EMT in RPE cells under high glucose conditions.

COMMD3-Mediated Endosomal Trafficking of HER2 Inhibits the Progression of Ovarian Carcinoma

The dysregulated endocytic traffic of oncogenic receptors, such as the EGFR family especially HER2, contributes to the uncontrolled activation of the downstream oncogenic signaling and progression of various carcinomas, including 90% of ovarian carcinoma. However, the key regulators in the intracellular trafficking of HER2 and their impacts for cancer progression remain largely unknown. In this study, through a genome-wide CRISPR/Cas9 screening for key genes affecting the peritoneal disseminated metastasis of ovarian carcinoma, we identified a member of COMMD family, that is, COMMD3, as a key regulator in the endosomal trafficking of HER2. In the patients with high-grade serous ovarian carcinoma (HGSOC), the expression of COMMD3 is dramatically decreased in the peritoneal disseminated ovarian carcinoma cells comparing with that in the primary ovarian carcinoma cells. COMMD3 greatly inhibits the proliferation, migration, and epithelial-mesenchymal transition (EMT) of HGSOC cells, and dramatically suppresses the tumor growth, the formation of malignant ascites, and the peritoneal dissemination of cancer cells in the orthotopic murine model of HGSOC. Further transcriptome analysis reveals that silencing COMMD3 boosts the activation of HER2 downstream signaling. As a component in the Retriever-associated COMMD/CCDC22/CCDC93 complex responsible for the recognition and recycling of membrane receptors, COMMD3 physically interacts with HER2 for directing it to the slow recycling pathway, leading to the attenuated downstream tumor-promoting signaling.

IMPLICATIONS

Collectively, this study reveals a novel HER2 inactivation mechanism with a high value for the clinic diagnosis of new ovarian carcinoma types and the design of new therapeutic strategy.

miR-451a suppresses papillary thyroid cancer cell proliferation and invasion and facilitates apoptosis through targeting DCBLD2 and AKT1

Papillary thyroid cancer (PTC) is a common malignancy. MicroRNAs (miRNAs) may act as oncogenes or tumor suppressor genes. However, the role of miR-451a in PTC is not fully understood. Hence, the objective of the study was to research the effect and mechanism of miR-451a in PTC. Differentially expressed miRNAs between GSE113629 and GSE103996 databases were assessed by Venn diagram. miR-451a and its downstream target genes were assessed by RT-PCR and Western blot. The proliferation, invasion, and apoptosis were determined by CCK-8, EdU, transwell, and flow cytometry assays. Dual-luciferase reporter assay were used to evaluated the target of miR-451a. Xenografted tumors was used to explore the function of miR-451a in vivo. Pathological changes and related protein expression were measured by HE staining and immunohistochemistry. MiR-451a was downregulated in PTC tissues and blood, and low expression of miR-451a was related to short overall survival, serious lymph node metastasis and high TNM grade in PTC patients. Moreover, increase of miR-451a restrained the proliferation and invasion and accelerated the apoptosis. Furthermore, miR-451a repressed VEGF signaling pathway. Importantly, miR-451a was demonstrated to target DCBLD2 and AKT1. Overexpression of DCBLD2 and AKT1 could restore the effect of miR-451a on PTC cells. In addition, miR-451a reduced the growth of xenografted tumors in vivo. The data suggested that miR-451a attenuated the proliferation, invasion and promoted apoptosis in PTC cells via inhibiting DCBLD2 and AKT1.

An Inflammatory Response-Related Gene Signature Can Predict the Prognosis and Impact the Immune Status of Lung Adenocarcinoma

Lung adenocarcinoma (LUAD) accounts for a cancer with high heterogeneity and poor prognostic outcome. Nonetheless, it is still unknown about the relation between inflammatory response-related genes (IRGs) and LUAD. This study used LASSO-Cox regression for establishing the multigene prognostic signature based on TCGA and the GSE31210 cohorts. In addition, gene set enrichment analysis (GSEA) was performed for GO and KEGG analyses. By contrast, single-sample GSEA (ssGSEA) investigated immune cell infiltration scores as well as the immune pathway activity. We also conducted qRT-PCR and IHC to evaluate prognostic gene expression at protein and mRNA levels within LUAD and adjacent healthy samples. As a result, a novel prognostic signature involving 10 IRGs was identified. Furthermore, the signature has been validated as being important in functional analysis, TME, drug sensitivity, and prognosis prediction in LUAD. Moreover, prognostic genes showed significant expression at protein and mRNA levels in LUAD compared with normal samples. The signature involving 10 IRGs could potentially predict LUAD prognosis.

Pan-cancer analyses identify DCBLD2 as an oncogenic, immunological, and prognostic biomarker

Discoidin, CUB, and LCCL domain-containing protein 2 (DCBLD2) is a two-domain transmembrane protein-coding gene located on chromosome 3, the protein expressed by which acts as the membrane receptor of semaphorin and vascular endothelial growth factor during the development of axons and blood vessels. Although several research evidences at the cellular and clinical levels have associated DCBLD2 with tumorigenesis, nothing is known regarding this gene from a pan-cancer standpoint. In this study, we systematically analyzed the influence of DCBLD2 on prognosis, cancer staging, immune characteristics, and drug sensitivity in a variety of cancers based on a unified and standardized pan-cancer dataset. In addition, we performed GO enrichment analyses and KEGG analyses of DCBLD2-related genes and DCBLD2-binding proteins. Our results showed that DCBLD2 is a potential oncogenic, immunological as well as a prognostic biomarker in terms of pan-cancer, and is expected to contribute to the improvement of tumor prognosis and the development of targeted therapy.

Debris-stimulated tumor growth: a Pandora's box?

Current cancer therapies aim at eradicating cancer cells from the body. However, killing cells generates cell “debris” which can promote tumor progression. Thus, therapy can be a double-edged sword. Specifically, injury and debris generated by cancer therapies, including chemotherapy, radiation, and surgery, may offset their benefit by promoting the secretion of pro-tumorigenic factors (e.g., eicosanoid-driven cytokines) that stimulate regrowth and metastasis of surviving cells. The debris produced by cytotoxic cancer therapy can also contribute to a tumor microenvironment that promotes tumor progression and recurrence. Although not well understood, several molecular mechanisms have been implicated in debris-stimulated tumor growth that we review here, such as the involvement of extracellular vesicles, exosomal miR-194-5p, Bax, Bak, Smac, HMGB1, cytokines, and caspase-3. We discuss the cases of pancreatic and other cancer types where debris promotes postoperative tumor recurrence and metastasis, thus offering a new opportunity to prevent cancer progression intrinsically linked to treatment by stimulating resolution of tumor-promoting debris.

Eicosanoid regulation of debris-stimulated metastasis

Cancer therapy, such as chemotherapy, induces tumor cell death (“debris”), which can stimulate metastasis. Chemotherapy-generated debris upregulates soluble epoxide hydrolase (sEH) and the prostaglandin E₂ receptor 4 (EP4), which triggers a macrophage-derived storm of proinflammatory and proangiogenic lipid autacoid and cytokine mediators. Although sEH inhibitors and EP4 antagonists are in clinical development for multiple inflammatory diseases, their combined role in cancer is unknown. Here, we show that the synergistic antitumor activity of sEH and EP4 inhibition suppresses hepato-pancreatic tumor growth, without overt toxicity, via macrophage phagocytosis of debris and counterregulation of a debris-stimulated cytokine storm. Thus, stimulating the resolution of inflammation via combined inhibition of sEH and EP4 may be an approach for preventing metastatic progression driven by cancer therapy.

Cancer therapy reduces tumor burden via tumor cell death (“debris”), which can accelerate tumor progression via the failure of inflammation resolution. Thus, there is an urgent need to develop treatment modalities that stimulate the clearance or resolution of inflammation-associated debris. Here, we demonstrate that chemotherapy-generated debris stimulates metastasis by up-regulating soluble epoxide hydrolase (sEH) and the prostaglandin E₂ receptor 4 (EP4). Therapy-induced tumor cell debris triggers a storm of proinflammatory and proangiogenic eicosanoid-driven cytokines. Thus, targeting a single eicosanoid or cytokine is unlikely to prevent chemotherapy-induced metastasis. Pharmacological abrogation of both sEH and EP4 eicosanoid pathways prevents hepato-pancreatic tumor growth and liver metastasis by promoting macrophage phagocytosis of debris and counterregulating a protumorigenic eicosanoid and cytokine storm. Therefore, stimulating the clearance of tumor cell debris via combined sEH and EP4 inhibition is an approach to prevent debris-stimulated metastasis and tumor growth.