IGHG1 induces EMT in gastric cancer cells by regulating TGF-β/SMAD3 signaling pathway

IFIT1 + neutrophil is a causative factor of immunosuppressive features of poorly cohesive carcinoma (PCC)

The importance of the immune microenvironment in poorly cohesive carcinoma (PCC) has been highlighted due to its limited response rate to conventional therapy and emerging treatment resistance. A combination of clinical cohorts, bioinformatics analyses, and functional/molecular experiments revealed that high infiltration of Interferon Induced Protein with Tetratricopeptide Repeats 1 (IFIT1) + tumor-associated neutrophils (TANs) is a distinguishing feature of PCC patients. Upregulation of IFIT1 + TANs promote migration and invasion of gastric cancer (GC) cell lines (MKN45 and MKN74) and stimulates the growth of cell-derived xenograft models. Besides, by promoting macrophage secreted phosphoprotein 1 (SPP1) expression and facilitating cancer-associated fibroblast and endothelial cell recruitment and activation through TANs, IFIT1 promotes a mesenchymal phenotype, which is associated with a poor prognosis. Importantly, compared to non-PCC (NPCC), PCC tumors is more immunosuppressive. Mechanistically, IFIT1 can be stimulated by IFN-γ and contributes to the expression of Programmed Cell Death 1 Ligand (PDL1) in TANs. We demonstrated in mouse models that IFIT1 + PDL1 + TANs can induce acquired resistance to anti-PD-1 immunotherapy, which may be responsible for the difficulty of PCC patients to benefit from immunotherapy. This work highlights the role of IFIT1 + TANs in mediating the remodeling of the tumor immune microenvironment and immunotherapeutic resistance and introduces IFIT1 + TANs as a promising target for precision therapy of PCC.

Alterations in gene expression and microbiome composition upon calcium-sensing receptor deletion in the mouse esophagus

The calcium-sensing receptor (CaSR), a G protein-coupled receptor, regulates Ca2+ concentration in plasma by regulating parathyroid hormone secretion. In other tissues, it is reported to play roles in cellular differentiation and migration and in secretion and absorption. We reported previously that CaSR can be conditionally deleted in the mouse esophagus. This conditional knockout (KO) (EsoCaSR-/-) model showed a significant reduction in the levels of adherens and tight junction proteins and had a marked buildup of bacteria on the luminal esophageal surface. To further examine the role of CaSR, we used RNA sequencing to determine gene expression profiles in esophageal epithelia of control and EsoCaSR-/-mice RNA Seq data indicated upregulation of gene sets involved in DNA replication and cell cycle in EsoCaSR-/-. This is accompanied by the downregulation of gene sets involved in the innate immune response and protein homeostasis including peptide elongation and protein trafficking. Ingenuity pathway analysis (IPA) demonstrated that these genes are mapped to important biological networks including calcium and Ras homologus A (RhoA) signaling pathways. To further explore the bacterial buildup in EsoCaSR-/- esophageal tissue, 16S sequencing of the mucosal-associated bacterial microbiome was performed. Three bacterial species, g_Rodentibacter, s_Rodentibacter_unclassified, and s_Lactobacillus_hilgardi were significantly increased in EsoCaSR-/-. Furthermore, metagenomic analysis of 16S sequences indicated that pathways related to oxidative phosphorylation and metabolism were downregulated in EsoCaSR-/- tissues. These data demonstrate that CaSR impacts major pathways of cell proliferation, differentiation, cell cycle, and innate immune response in esophageal epithelium. The disruption of these pathways causes inflammation and significant modifications of the microbiome.NEW & NOTEWORTHY Calcium-sensing receptor (CaSR) plays a significant role in maintaining the barrier function of esophageal epithelium. Using RNA sequencing, we show that conditional deletion of CaSR from mouse esophagus causes upregulation of genes involved in DNA replication and cell cycle and downregulation of genes involved in the innate immune response, protein translation, and cellular protein synthesis. Pathway analysis shows disruption of signaling pathways of calcium and actin cytoskeleton. These changes caused inflammation and esophageal dysbiosis.

Proteomic and metabolomic features in patients with HCC responding to lenvatinib and anti-PD1 therapy

Combination therapy (lenvatinib/programmed death-1 inhibitor) is effective for treating unresectable hepatocellular carcinoma (uHCC). We reveal that responders have better overall and progression-free survival, as well as high tumor mutation burden and special somatic variants. We analyze the proteome and metabolome of 82 plasma samples from patients with hepatocellular carcinoma (HCC; n = 51) and normal controls (n = 15), revealing that individual differences outweigh treatment differences. Responders exhibit enhanced activity in the alternative/lectin complement pathway and higher levels of lysophosphatidylcholines (LysoPCs), predicting a favorable prognosis. Non-responders are enriched for immunoglobulins, predicting worse outcomes. Compared to normal controls, HCC plasma proteins show acute inflammatory response and platelet activation, while LysoPCs decrease. Combination therapy increases LysoPCs/phosphocholines in responders. Logistic regression/random forest models using metabolomic features achieve good performance in the prediction of responders. Proteomic analysis of cancer tissues unveils molecular features that are associated with side effects in responders receiving combination therapy. In conclusion, our analysis identifies plasma features associated with uHCC responders to combination therapy.

Molecular landscape of congenital vertebral malformations: recent discoveries and future directions

Vertebral malformations (VMs) pose a significant global health problem, causing chronic pain and disability. Vertebral defects occur as isolated conditions or within the spectrum of various congenital disorders, such as Klippel-Feil syndrome, congenital scoliosis, spondylocostal dysostosis, sacral agenesis, and neural tube defects. Although both genetic abnormalities and environmental factors can contribute to abnormal vertebral development, our knowledge on molecular mechanisms of numerous VMs is still limited. Furthermore, there is a lack of resource that consolidates the current knowledge in this field. In this pioneering review, we provide a comprehensive analysis of the latest research on the molecular basis of VMs and the association of the VMs-related causative genes with bone developmental signaling pathways. Our study identifies 118 genes linked to VMs, with 98 genes involved in biological pathways crucial for the formation of the vertebral column. Overall, the review summarizes the current knowledge on VM genetics, and provides new insights into potential involvement of biological pathways in VM pathogenesis. We also present an overview of available data regarding the role of epigenetic and environmental factors in VMs. We identify areas where knowledge is lacking, such as precise molecular mechanisms in which specific genes contribute to the development of VMs. Finally, we propose future research avenues that could address knowledge gaps.

miRNA/epithelial-mesenchymal axis (EMT) axis as a key player in cancer progression and metastasis: A focus on gastric and bladder cancers

The metastasis a major hallmark of tumors that its significant is not only related to the basic research, but clinical investigations have revealed that majority of cancer deaths are due to the metastasis. The metastasis of tumor cells is significantly increased due to EMT mechanism and therefore, inhibition of EMT can reduce biological behaviors of tumor cells and improve the survival rate of patients. One of the gaps related to cancer metastasis is lack of specific focus on the EMT regulation in certain types of tumor cells. The gastric and bladder cancers are considered as two main reasons of death among patients in clinical level. Herein, the role of EMT in regulation of their progression is evaluated with a focus on the function of miRNAs. The inhibition/induction of EMT in these cancers and their ability in modulation of EMT-related factors including ZEB1/2 proteins, TGF-β, Snail and cadherin proteins are discussed. Moreover, lncRNAs and circRNAs in crosstalk of miRNA/EMT regulation in these tumors are discussed and final impact on cancer metastasis and response of tumor cells to the chemotherapy is evaluated. Moreover, the impact of miRNAs transferred by exosomes in regulation of EMT in these cancers are discussed.

NSG1 promotes glycolytic metabolism to enhance Esophageal squamous cell carcinoma EMT process by upregulating TGF-β

As a highly enriched endosomal protein within neuronal cells, NSG1 has been discovered to facilitate the process of epithelial-mesenchymal transition (EMT) in esophageal squamous cell carcinoma (ESCC). However, the precise mechanisms behind this phenomenon have yet to be elucidated. The pivotal role of transforming growth factor-β (TGF-β) in triggering the EMT and its significant contribution towards tumor metabolic reprogramming-responsible for EMT activation-has been robustly established. Nevertheless, the extent of TGF-β involvement in the NSG1-mediated EMT within ESCC and the processes through which metabolic reprogramming participates remain ambiguous. We accessed an array of extensive public genome databases to analyze NSG1 expression in ESCC. Regulation of TGF-β by NSG1 was analyzed by transcriptome sequencing, quantitative Real-Time PCR (qRT-PCR), co-immunoprecipitation (CO-IP), and immunofluorescence (IF). Additionally, cellular functional assays and western blot analyses were conducted to elucidate the effect of NSG1 on TGF-β/Smad signaling pathway, as well as its role in ESCC cell metastasis and proliferation. We validated the influence of the NSG1/TGF-β axis on metabolic reprogramming in ESCC by measuring extracellular acidification, glucose uptake, and lactate production. Our findings identify an oncogenic role for NSG1 in ESCC and show a correlation between high NSG1 expression and poor prognosis in ESCC patients. Additional research indicated TGF-β's involvement in the NSG1-induced EMT process. From a mechanistic perspective, NSG1 upregulates TGF-β, activating the TGF-β/Smad signaling pathway and subsequently fostering the EMT process by inducing cell metabolic reprogramming-evident from elevated glycolysis levels. In conclusion, our study highlights the NSG1/TGF-β axis as a promising therapeutic target for ESCC.

Silencing of IGHG1 reverses the resistance of pancreatic cancer to multidrug chemotherapy by modulating autophagy

BACKGROUND

Pancreatic cancer is one of the most aggressive tumors with a high-mortality rate. First-line drugs include 5-fluorouracil (5-FU), gemcitabine (GEM), and oxaliplatin (OXA). Resistance to 5-FU, GEM, and OXA is a major challenge. Immunoglobulin heavy chain F1 (IGHG1) participates in the regulation of cancer progression. It is still unclear how IGHG1 affects 5-FU, GEM, and OXA in pancreatic cancer.

METHODS

The expression status of IGHG1 in pancreatic cancer was analyzed through bioinformatics tools. IGHG1 expression in pancreatic cancer tissues and cells was determined via RT-qPCR. Cell counting kit 8 assays, and flow cytometry analysis were utilized to detect the impact of IGHG1,5-FU, GEM, and OXA on cell proliferation and apoptosis. Western blotting was utilized to detect changes in the levels of the autophagy-associated proteins LC3, Beclin-1, p62, and ATG5. Immunofluorescence assays were employed to determine LC3 expression in cells. Xenograft experiments were conducted on nude mice to study tumor growth.

RESULTS

IGHG1 was overexpressed in pancreatic cancer cells and tissues. IGHG1 expression was downregulated by 5-FU, GEM, or OXA treatment in cells. Treatment with 5-FU, GEM, or OXA repressed viability and promoted apoptosis and autophagy in pancreatic cancer cells. IGHG1 silencing exhibited the same results. Furthermore, IGHG1 depletion notably strengthened the effects of 5-FU, GEM, and OXA on pancreatic cancer cell viability, apoptosis, and autophagy. The combination of IGHG1 depletion with 5-FU, GEM, or OXA significantly reduced tumor growth in vivo.

CONCLUSION

Silencing of IGHG1 could enhance 5-FU, GEM, or OXA function in pancreatic cancer and reverse resistance by regulating apoptosis and autophagy.

CSTF2T up-regulates IGHG1 by binding to ZEB1 to promote melanoma cell proliferation, migration, and invasion

OBJECTIVES

Melanoma progression involves multiple molecular pathways. In this study, we explored the effect of immunoglobulin heavy constant gamma 1 (IGHG1) on melanoma progression.

METHODS

IGHG1, zinc finger E-box binding homeobox 1 (ZEB1), and cleavage stimulation factor subunit 2 tau variant (CSTF2T) expression levels were measured by quantitative reverse-transcription polymerase chain reaction and western blot. BALB/c nude mice were subcutaneously injected with A375 cells to develop a transplantation tumor model, 4 weeks after which the tumor tissues were collected. Cell proliferation, cell invasion, and cell migration of A375 and SK-MEL-28 cells were measured after gain- and loss-of-function of IGHG1, ZEB1, and CSTF2T. Binding of ZEB1 to the IGHG1 promoter was assayed by chromatin immunoprecipitation and dual-luciferase reporter gene assays, while binding of CSTF2T to ZEB1 mRNA was investigated by RNA immunoprecipitation and RNA pull-down assays.

RESULTS

IGHG1, ZEB1, and CSTF2T were all highly expressed in human melanoma cell lines. In A375 and SK-MEL-28 cells, ZEB1 binds directly to the IGHG1 promoter. ZEB1 silencing reduced IGHG1 expression and melanoma cell proliferative, invasive, and migratory properties, and these cellular effects were nullified by overexpression of IGHG1. CSTF2T binds directly to ZEB1 mRNA. Silencing of CSTF2T diminished ZEB1 expression and restrained melanoma cell proliferative, invasive, and migratory capabilities. The impacts of CSTF2T silencing on melanoma cells were counteracted by concomitant overexpression of ZEB1. CSTF2T knockdown reduced tumor volume and weight in nude mice.

CONCLUSIONS

The CSTF2T-ZEB1-IGHG1 axis promotes melanoma cell proliferation and invasion.

Integrated analysis of genomic and transcriptomic data for the discovery of splice-associated variants in cancer

Somatic mutations within non-coding regions and even exons may have unidentified regulatory consequences that are often overlooked in analysis workflows. Here we present RegTools ( www.regtools.org ), a computationally efficient, free, and open-source software package designed to integrate somatic variants from genomic data with splice junctions from bulk or single cell transcriptomic data to identify variants that may cause aberrant splicing. We apply RegTools to over 9000 tumor samples with both tumor DNA and RNA sequence data. RegTools discovers 235,778 events where a splice-associated variant significantly increases the splicing of a particular junction, across 158,200 unique variants and 131,212 unique junctions. To characterize these somatic variants and their associated splice isoforms, we annotate them with the Variant Effect Predictor, SpliceAI, and Genotype-Tissue Expression junction counts and compare our results to other tools that integrate genomic and transcriptomic data. While many events are corroborated by the aforementioned tools, the flexibility of RegTools also allows us to identify splice-associated variants in known cancer drivers, such as TP53, CDKN2A, and B2M, and other genes.

High expression of IGHG1 promotes breast cancer malignant development by activating the AKT pathway

This study researched the exact function of IgG1 heavy chain (IGHG1) on breast cancer (BC) progression. IGHG1 level within BC and paired normal tissues was acquired in Gene Expression Profiling Interactive Analysis dataset. Meanwhile, this work harvested tumor and paired healthy tissues in 42 BC cases. siRNA targeting IGHG1 was transfected into BC cells. SC79 was used to treat the transfected BC cells. CCK-8 assay, clone formation experiment, BrdU assay, Transwell experiment and flow cytometry were carried out to measure the viability, colony formation, proliferation, invasion, and apoptosis of BC cells. Paclitaxel and cisplatin sensitivity of BC cells was evaluated by MTT assay. Real-time quantitative reverse transcription-polymerase chain reaction and Western-blot were performed for measuring mRNA and protein expression. The overexpressed IGHG1 indicated dismal BC survival. IGHG1 silencing attenuated the viability, invasion, proliferation, epithelial-mesenchymal transition, but enhanced the apoptosis of BC cells. IGHG1 silencing enhanced the paclitaxel and cisplatin sensitivity of BC cells. IGHG1 silencing suppressed the activity of the MEK, AKT, and ERK pathways. AKT agonist partially reversed the inhibition of IGHG1 silencing on BC cell malignant phenotype and resistance to paclitaxel and cisplatin. IGHG1 promotes the malignant development of BC by activating the AKT pathway. It may be an effective target for BC treatment.

Chondroitin polymerizing factor predicts a poor prognosis and promotes breast cancer progression via the upstream TGF-β1/SMAD3 and JNK axis activation

Aberrant composition of glycans in the tumor microenvironment (TME) contributes to tumor progression and metastasis. Chondroitin polymerizing factor (CHPF) is a glycosyltransferase that catalyzes the biosynthesis of chondroitin sulfate (CS). It is also correlated to transforming growth factor-β1 (TGF-β1) expression, a crucial mediator in the interaction of cancer cells with TME. In this study, we investigated the association of CHPF expression with the clinicopathological features of breast cancer (BRCA), as well the oncogenic effect and the underling mechanisms of CHPF upon BRCA cells. We found that CHPF expression is significantly increased in human BRCA tissues, and it is positively associated with TGF-β expression (r = 0.7125). The high-expression of CHPF predicts a poor prognosis and is positively correlated with tumor mass, lymph node metastasis, clinical staging and HER-2 negative-expression. The mechanistic study revealed that it promotes BRCA cell proliferation, migration and invasion through TGF-β1-induced SMAD3 and JNK activation in vitro, JNK (SP600125) or SMAD3 (SIS3) inhibitor can remove the promotion of CHPF upon cell proliferation, migration and invasion in MDA-MB-231 cells, which is derived from triple-negative breast cancer (TNBC). Collectively, our finding suggested CHPF may function as an oncogene and is highly expressed in human BRCA tissues. Pharmacological blockade of the upstream of JNK or SMAD3 signaling may provide a novel therapeutic target for refractory TNBC patients with CHPF abnormal high-expression.

Extracellular matrix stiffness mediates radiosensitivity in a 3D nasopharyngeal carcinoma model

Purpose

Radiotherapy is one of the essential treatment modalities for nasopharyngeal carcinoma (NPC), however, radioresistance still poses challenges. Three-dimensional (3D) tumor culture models mimic the in vivo growth conditions of cells more accurately than 2D models. This study is to compare the tumor biological behaviors of NPC cells in 2D, On-Surface 3D and Embedded 3D systems, and to investigate the correlation between radioresistance and extracellular matrix (ECM) stiffness.

Methods

The morphology and radioresistance of the human NPC cell line CNE-1 were observed in 2D and 3D systems. The CCK-8 assay, wounding healing assays, flow cytometry, soft agar assays, and western blot analysis were used to evaluate differences in biological behaviors such as proliferation, migration, cell cycle distribution, and stem cell activity. Different ECM stiffness systems were established by co-blending collagen and alginate in varying proportions. ECM stiffness was evaluated by compressive elastic moduli measurement and colony formation assay was used to assess radioresistance of NPC cells in systems with different ECM stiffness after irradiation.

Results

Compared to 2D models, the morphology of NPC cells in 3D culture microenvironments has more in common with in vivo tumor cells and 3D cultured NPC cells exhibit stronger radioresistance. Integrin β1 but not the epithelial-to-mesenchymal transition pathway in 3D models boost migration ability. Cell proliferation was enhanced, the proportion of tumor stem cells was increased, and G1/S phase arrest occurred in 3D models. NPC cells cultured in softer ECM systems (with low alginate proportions) exhibit striking resistance to ionizing radiation.

Conclusion

The tumor biological behaviors of NPC cells in 3D groups were obviously different from that of 2D. Radioresistance of NPC cells increased with the stiffness of ECM decreasing.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-022-02787-5.

Troponin C-1 Activated by E2F1 Accelerates Gastric Cancer Progression via Regulating TGF-β/Smad Signaling

BACKGROUND

Troponin C-1 (TNNC1) has been previously characterized as an oncogenic gene.

AIMS

This study aimed to reveal the roles of TNNC1 in gastric cancer and the potential underlying mechanisms.

METHODS

TNNC1 siRNAs and TNNC1 overexpression plasmid were used to alter its expression in AGS, MKN45, and HGC-27 cells. CCK-8 assay, colony formation, EdU assay, flow cytometry, transwell assay, and scratch test were conducted to measure the phenotype changes. In vivo effects of TNNC1 silence were confirmed by using a xenograft mouse model. Bioinformatics analysis was conducted to screen out the transcription factor and downstream signaling of TNNC1.

RESULTS

TNNC1 was highly expressed in gastric cancer tissues and cell lines, and its expression was associated with poor prognosis. TNNC1 silence suppressed the proliferation, migration, and invasion of AGS and MKN45 cells. However, TNNC1 silence induced apoptosis by mediating the cleavage of caspase-3 and caspase-9. Overexpression of TNNC1 in HGC-27 cells led to the contrary effects. The anti-tumor effects of TNNC1 silence were also confirmed in a xenograft animal model. E2F1 was validated as an upstream transcription factor of TNNC1. Effects of TNNC1 silence on AGS cell migration and invasion were attenuated by E2F1 overexpression. Besides, TGF-β/Smad was a downstream signaling pathway of TNNC1. The anti-tumor impacts of TNNC1 silence were weaken by SB431542 (a specific inhibitor of TGF-β signaling) while accelerated by TGF-β.

CONCLUSION

TNNC1 activated by E2F1 functioned as an oncogenic gene through regulating TGF-β/Smad signaling. TNNC1 was suggested as a potential molecular drug target of gastric cancer.

Improved profiling of low molecular weight serum proteome for gastric carcinoma by data-independent acquisition

Low molecular weight proteins (LMWPs) in the bloodstream participate in various biological processes and are closely associated with disease status, whereas identification of serous LMWPs remains a great technical challenge due to the wide dynamic range of protein components. In this study, we constructed an integrated LMWP library by combining the LMWPs obtained by three enrichment methods (50% ACN, 20% ACN + 20 mM ABC, and 30 kDa) and their fractions identified by the data-dependent acquisition method. With this newly constructed library, we comprehensively profiled LMWPs in serum using data-independent acquisition and reliably achieved quantitative results for 75% serous LMWPs. When applying this strategy to quantify LMWPs in human serum samples, we could identify 405 proteins on average per sample, of which 136 proteins were with a MW less than 30 kDa and 293 proteins were with a MW less than 65 kDa. Of note, pre- and post-operative gastric carcinoma (GC) patients showed differentially expressed serous LWMPs, which was also different from the pattern of LWMP expression in healthy controls. In conclusion, our results showed that LMWPs could efficiently distinguish GC patients from healthy controls as well as between pre- and post-operative statuses, and more importantly, our newly developed LMWP profiling platform could be used to discover candidate LMWP biomarkers for disease diagnosis and status monitoring.

MT1G inhibits the growth and epithelial-mesenchymal transition of gastric cancer cells by regulating the PI3K/AKT signaling pathway

Gastric carcinoma (GC) is a malignant tumor that has high mortality and morbidity worldwide. Although many efforts have been focused on the development and progression of GC, the underlying functional regulatory mechanism of GC needs more clarification. Metallothionein 1G (MT1G) is a member of the metallothionein family (MTs), and hypermethylation of MT1G occurred in a variety of cancers, including gastric cancer. However, the functional mechanism of MT1G in GC remains unclear. Here, we demonstrated that MT1G was down-regulated in GC tissues and cells. Overexpression of MT1G inhibited cell proliferation, foci formation and cell invasion, while knockdown of MT1G increased cell proliferation, foci formation and cell invasion. In addition, MT1G overexpression inhibited cell cycle progression and MT1G deficiency exerted opposite phenotype. p-AKT was negatively regulated by MT1G. In summary, our study reveals that MT1G exerts crucial role in regulating of cell proliferation and migration of gastric cancer, providing new insights for MT1G-related pathogenesis and a basis for developing new strategies for treatment of GC.

Upregulated Expression of Cancer-Derived Immunoglobulin G Is Associated With Progression in Glioma

Objective

Gliomas are the most aggressive intracranial tumors accounting for the vast majority of brain tumors with very poor prognosis and overall survival (OS). Cancer-derived immunoglobulin G (cancer-IgG) has been found to be widely expressed in several malignancies such as breast cancer, colorectal cancer, and lung cancer. Cancer-IgG could promote tumorigenesis and progression. However, its role in glioma has not been revealed yet.

Methods

We mined open databases including the Chinese Glioma Genome Atlas (CGGA), The Cancer Genome Atlas (TCGA), and the Gene Expression Omnibus (GEO) to study the role of IGHG1, which encodes cancer-IgG in glioma. Examination of the differential expression of IGHG1 was carried out in the GEO and TCGA databases. Furthermore, its expression in different molecular subtypes was analyzed. Stratified analysis was performed with clinical features. Subsequently, immune infiltration analysis was conducted using single-sample gene set enrichment analysis (ssGSEA). GSEA was performed to reveal the mechanisms of IGHG1. Lastly, immunohistochemistry was processed to validate our findings.

Results

In this study, we found that the expression of IGHG1 was higher in glioma and molecular subtypes with poor prognosis. The overall survival of patients with a high expression of IGHG1 was worse in the stratified analysis. Immune infiltration analysis indicated that the expression level of IGHG1 was positively correlated with the stromal score, ESTIMATE score, and immune score and negatively correlated with tumor purity. Results from the GSEA and DAVID demonstrated that IGHG1 may function in phagosome, antigen processing and presentation, extracellular matrix structural constituent, antigen binding, and collagen-containing extracellular matrix. Finally, immunohistochemistry assay validated our findings that patients with a high expression of cancer-IgG had poor OS and disease-free survival (DFS).

Conclusion

Cancer-IgG is a promising biomarker of diagnosis and treatment for patients with glioma.

Down-regulation of IGHG1 enhances Protoporphyrin IX accumulation and inhibits hemin biosynthesis in colorectal cancer by suppressing the MEK-FECH axis

Immunoglobulin γ-1 heavy chain constant region (IGHG1) is a functional isoform of immunoglobulins and plays an important role in the cytolytic activity of immune effector cells. Dysregulated IGHG1 was implicated in the occurrence and development of various tumors. Protoporphyrin IX (PpIX) is an endogenous fluorophore and is used in photodynamic therapy, which induces the generation of reactive oxygen species to initiate the death of tumor cells. However, the roles of IGHG1 in the colorectal cancer cell proliferation and PpIX accumulation have not been reported yet. Data from qRT-PCR and western blot analysis showed that IGHG1 was up-regulated in the colorectal cancer cells. Colorectal cancer cells were then transfected with shRNA targeting IGHG1 to down-regulate IGHG1 and conducted with Cell Counting Kit 8 (CCK8) and colony formation assays. Results demonstrated that shRNA-mediated down-regulation of IGHG1 decreased cell viability of colorectal cancer and suppressed cell proliferation. Moreover, PpIX accumulation was promoted and the hemin content was decreased by the silence of IGHG1. Interference of IGHG1 reduced the phosphorylated extracellular signal-regulated kinase (ERK) and ferrochelatase (FECH) expression, resulting in retarded cell proliferation in an MEK-FECH axis-dependent pathway.

IGHG1 upregulation promoted gastric cancer malignancy via AKT/GSK-3β/β-Catenin pathway

Background

Despite current advances in gastric cancer treatment, disease metastasis and chemo-resistance remain as major hurdles against better overall prognosis. Previous studies indicated that IGHG1 as well as -Catenin serve as important regulators of tumor cellular malignancy. Therefore, understanding detailed molecular mechanism and identifying druggable target will be of great potentials in future therapeutic development.

Methods

Surgical tissues and gastric cancer cell lines were retrieved to evaluate IGHG1 expression for patients with or without lymph node/distal organ metastasis. Functional assays including CCK8 assay, Edu assay, sphere formation assay and transwell assay, wound healing assay, etc. were subsequently performed to evaluate the impact of IGHG1/-catenin axis on tumor cell proliferation, migration and chemo-resistance.

Results

Gastric cancer tissues and tumor cell lines demonstrated significantly higher level of IGHG1. Functional study further demonstrated that IGHG1 promoted proliferative and migration as well as chemo-resistance of gastric cancer tumor cells. Further experiments indicated that IGHG1 activated AKT/GSK-3/-Catenin axis, which played crucial role in regulation of proliferative and chemo-resistance of gastric cancer cells.

Conclusion

This study provided novel evidences that IGHG1 acted as oncogene by promotion of gastric cancer cellular proliferation, migration and chemo-resistance. Our research further suggested that IGHG1/AKT/GSK-3β/β-Catenin axis acted as novel pathway which regulated gastric cancer cellular malignant behavior. Our research might inspire future therapy development to promote overall prognosis of gastric cancer patients.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12935-021-02098-1.