DSCC1 interacts with HSP90AB1 and promotes the progression of lung adenocarcinoma via regulating ER stress

Abstract

Lung cancer is a leading cause of cancer-related deaths, and the most common type is lung adenocarcinoma (LUAD). LUAD is frequently diagnosed in people who never smoked, patients are always diagnosed at advanced inoperable stages, and the prognosis is ultimately poor. Thus, there is an urgent need for the development of novel targeted therapeutics to suppress LUAD progression. In this study, we demonstrated that the expression of DNA replication and sister chromatid cohesion 1 (DSCC1) was higher in LUAD samples than normal tissues, and the overexpression of DSCC1 or its coexpressed genes were highly correlated with poor outcomes of LUAD patients, highlighting DSCC1 might be involved in LUAD progression. Furthermore, the expression of DSCC1 was positively correlated with multiple genetic mutations which drive cancer development, including TP53, TTN, CSMD, and etc. More importantly, DSCC1 could promote the cell proliferation, stemness, EMT, and metastatic potential of LUAD cells. In addition, DSCC1 interacted with HSP90AB1 and promoted the progression of LUAD via regulating ER stress. Meanwhile, DSCC1 expression negatively correlated with immune cell infiltration in lung cancer, and DSCC1 positively regulated the expression of PD-L1 in LUAD cells. Collectively, this study revealed that DSCC1 is a novel therapeutic target to treat LUAD and a biomarker for predicting the efficiency of PD-1/PD-L1 blockade treatment.

Keywords: DSCC1; HSP90AB1; Lung adenocarcinoma; Metastasis; PD-L1; Proliferation; Stemness.

Fig. 1

DSCC1 is overexpressed in LUAD and predicts poor outcome of LUAD patients. (A-D) The data was obtained from UALCAN (http://ualcan.path.uab.edu/index.html). TCGA; Gene: DSCC1; TCGA dataset: LUAD; Expression; DSCC1 expression based on Sample type (A), Tumor histology (B), individual cancer stages (C). CPTAC; Gene: DSCC1; CPTAC dataset: LUAD; Total protein (D). (E,F) The data was obtained from The Human Protein Atlas (https://www.proteinatlas.org/). (G) The results were collected from PrognoScan (http://dna00.bio.kyutech.ac.jp/PrognoScan/index.html). Overall Survival: Dataset - GSE13213 (left panel); Relapse Free Survival: Dataset - GSE31210 (right panel). (H) The data was collected from CAMOIP (https://www.camoip.net/). COX Regression; Gene expression; TCGA-Cohort: LUAD-OS; Gene: DSCC1. (I) The data was obtained from Sangerbox 3.0 (http://sangerbox.com/home.html). Gene expression and mutation landscape; Gene: DSCC1; Cancer: LUAD.

Fig. 2

The high levels of DSCC1 coexpressed genes predict poor outcomes of LUAD patients. (A) The coexpressed genes of DSCC1 were obtained from LinkedOmics (http://www.linkedomics.org/admin.php). TOP 20 genes were identified to construct a protein-protein interaction network using STRING (https://www.string-db.org/). (B,C,D) The results were collected from KM plotter (http://kmplot.com/analysis/index.php?p=background). The overall survival times of lung cancer patients were shown (OS, n = 1927)

Fig. 3

DSCC1 promotes LUAD cell proliferation and stemness. (A-B) The data was collected from LinkedOmics. Gene: DSCC1; Sample cohort: TCGA_LUAD; Institute: UNC; Data type: RNA seq; Platform: HiSeq RNA; Statistical Method: Pearson correlation test; Patients: 515; Enrichment Analysis: GSEA; Rank Criteria (from LinkFinder Result): FDR. (C) LUAD cells were transfected with control siRNA or siDSCC1 for 48 h, and the expression of DSCC1 was determined. (D) LUAD cells were transfected with control siRNA or siDSCC1 for the indicated times, and SRB was used to detect cell proliferation. (E) The data was obtained from Sangerbox 3.0 (http://sangerbox.com/home.html). Cancer stemness and gene expression: Gene: DSCC1; Data source: RNAss; Data transformation: log2(x + 0.001); Pearson. (F,G) LUAD cells were transfected with DSCC1 siRNA and control siRNA and the colony formation was performed. (H) The data was obtained from UALCAN. (I) LUAD cells were transfected with DSCC1 siRNA and control siRNA for 48 h, and the mRNA level of indicated proteins were detected by quantitative PCR analysis. (J) LUAD cells were transfected with DSCC1 overexpressing plasmid and empty vector for 48 h, and the mRNA level of indicated proteins were detected by quantitative PCR analysis. (K) LUAD cells were transfected with DSCC1 siRNA and control siRNA for 48 h, and the expression of indicated proteins were detected by western blot

Fig. 4

DSCC1 siRNA suppresses the metastatic potential of LUAD cells. (A) The data was collected from LinkedOmics. (B) The data was obtained from UALCAN. (C) The result was collected from TNMplot (https://tnmplot.com/analysis/). Gene expression comparison: compare tumor, normal and metastasis; Gene chip data; Gene: DSCC1; Tissue: Lung. (D) LUAD cells were transfected with DSCC1 siRNA and control siRNA for 48 h, and the migrative and invasive abilities of LUAD cells were determined by Transwell assay. (E-F) LUAD cells were transfected with DSCC1 siRNA and control siRNA for 24 h, and the migration was determined by wound healing assay. (G) LUAD cells were transfected with DSCC1 siRNA and control siRNA for 48 h, and the expression of indicated proteins were detected by western blot. (H) The data was collected from LinkedOmics.

Fig. 5

DSCC1 promotes the metastatic potential of LUAD cells. (A-B) LUAD cells were transfected with DSCC1 overexpressing plasmid and empty vector for 48 h, and the migrative and invasive abilities of LUAD cells were determined by Transwell assay. (C-D) LUAD cells were transfected with DSCC1 overexpressing plasmid and empty vector for 24 h, and the migration was determined by wound healing assay. (E) LUAD cells were transfected with DSCC1 overexpressing plasmid and empty vector for 48 h, and the expression of indicated proteins were detected by western blot

Fig. 6

DSCC1 interacts with HSP90AB1 and promotes the progression of LUAD. (A) LUAD cells were collected, and immunoprecipitations with DSCC1 antibody or IgG were performed. DSCC1 interacting proteins were identified by immunoprecipitation coupled to mass spectrometry. (B-C) DSCC1 coexpressed genes were identified by UALCAN platform, and A Venn diagram was generated by overlapping DSCC1 coexpressed genes and DSCC1 interacting proteins. (D) Immunoprecipitation was performed to verify the interaction between DSCC1 and HSP90AB1. (E) The data was obtained from LinkedOmics. (F-G) LUAD cells with high level of DSCC1 were transfected with control siRNA and HSP90AB1 siRNA for 24 h, and migrative abilities of LUAD cells were determined by wound healing assay. (H-I) LUAD cells with high level of DSCC1 were transfected with control siRNA and HSP90AB1 siRNA for 48 h, and the expression of the indicated proteins were detected by western blot

Fig. 7

DSCC1 promotes LUAD progression via regulating ER stress and HSP90AB1. (A) The data was obtained from LinkedOmics. (B) LUAD cells were treated with control siRNA and DSCC1 siRNA for 48 h, and the expression of the indicated proteins were detected by western blot. (C) LUAD cells were treated with DSCC1 overexpressing plasmid and empty vector for 48 h, and the expression of the indicated proteins were detected by western blot. (D-E) LUAD cells were transfected with DSCC1 plasmid and empty vector for 48 h, then treated with thapsigargin (100 nM for NCI-H1299, and 10 nM for A549) for 24 h, and the migrative ability of LUAD cells were detected. (F) LUAD cells overexpressing DSCC1 were transfected with control siRNA and HSP90AB1 siRNA for 48 h, and the expression of the indicated proteins were detected by western blot

Fig. 8

DSCC1 negatively correlated with tumor-infiltrating immune cells. (A-C) The data were collected from Sangerbox 3.0. Immune infiltration analysis, Immunocyte analysis (TIMER), and Immune checkpoint genes; Gene: DSCC1; Cancer: LUAD and LUSC. (D) The results were collected from TIMER (http://cistrome.org/TIMER/). (E) The data were collected from Sangerbox 3.0. (F) LUAD cells were transfected with DSCC1 siRNA and control siRNA for 48 h, and the expression of indicated proteins were determined. (G) LUAD cells were transfected with DSCC1 overexpressing plasmid and empty vector for 48 h, and the expression of indicated proteins were detected. (H) LUAD cells overexpressing DSCC1 were incubated with HSP90AB1 siRNA and control siRNA for 48 h, and the expression of indicated proteins were determined

Fig. 9

DSCC1 promotes the progression of LUAD via regulating HSP90AB1/STAT3 signaling pathway