TRIM22 confers poor prognosis and promotes epithelial-mesenchymal transition through regulation of AKT/GSK3β/β-catenin signaling in non-small cell lung cancer

PI3K/AKT pathway as a pivotal regulator of epithelial-mesenchymal transition in lung tumor cells

Lung cancer, as the leading cause of cancer related deaths, is one of the main global health challenges. Despite various progresses in diagnostic and therapeutic methods, there is still a high rate of mortality among lung cancer patients, which can be related to the lack of clinical symptoms to differentiate lung cancer from the other chronic respiratory disorders in the early tumor stages. Most lung cancer patients are identified in advanced and metastatic tumor stages, which is associated with a poor prognosis. Therefore, it is necessary to investigate the molecular mechanisms involved in lung tumor progression and metastasis in order to introduce early diagnostic markers as well as therapeutic targets. Epithelial-mesenchymal transition (EMT) is considered as one of the main cellular mechanisms involved in lung tumor metastasis, during which tumor cells gain the metastatic ability by acquiring mesenchymal characteristics. Since, majority of the oncogenic signaling pathways exert their role in tumor cell invasion by inducing the EMT process, in the present review we discussed the role of PI3K/AKT signaling pathway in regulation of EMT process during lung tumor metastasis. It has been reported that the PI3K/AKT acts as an inducer of EMT process through the activation of EMT-specific transcription factors in lung tumor cells. MicroRNAs also exerted their inhibitory effects during EMT process by inhibition of PI3K/AKT pathway. This review can be an effective step towards introducing the PI3K/AKT pathway as a suitable therapeutic target to inhibit the EMT process and tumor metastasis in lung cancer patients.

Intricate confrontation: Research progress and application potential of TRIM family proteins in tumor immune escape

BACKGROUND

Tripartite motif (TRIM) family proteins have more than 80 members and are widely found in various eukaryotic cells. Most TRIM family proteins participate in the ubiquitin-proteasome degradation system as E3-ubiquitin ligases; therefore, they play pivotal regulatory roles in the occurrence and development of tumors, including tumor immune escape. Due to the diversity of functional domains of TRIM family proteins, they can extensively participate in multiple signaling pathways of tumor immune escape through different substrates. In current research and clinical contexts, immune escape has become an urgent problem. The extensive participation of TRIM family proteins in curing tumors or preventing postoperative recurrence and metastasis makes them promising targets.

AIM OF REVIEW

The aim of the review is to make up for the gap in the current research on TRIM family proteins and tumor immune escape and propose future development directions according to the current progress and problems.

KEY SCIENTIFIC CONCEPTS OF REVIEW

This up-to-date review summarizes the characteristics and biological functions of TRIM family proteins, discusses the mechanisms of TRIM family proteins involved in tumor immune escape, and highlights the specific mechanism from the level of structure-function-molecule-pathway-phenotype, including mechanisms at the level of protein domains and functions, at the level of molecules and signaling pathways, and at the level of cells and microenvironments. We also discuss the application potential of TRIM family proteins in tumor immunotherapy, such as possible treatment strategies for combination targeting TRIM family protein drugs and checkpoint inhibitors for improving cancer treatment.

Neglected PTM in Animal Adipogenesis: E3-mediated Ubiquitination

Ubiquitination is a widespread post-transcriptional modification (PTM) that occurs during protein degradation in eukaryotes and participates in almost all physiological and pathological processes, including animal adipogenesis. Ubiquitination is a cascade reaction regulated by the activating enzyme E1, conjugating enzyme E2, and ligase E3. Several recent studies have reported that E3 ligases play important regulatory roles in adipogenesis. However, as a key influencing factor for the recognition and connection between the substrate and ubiquitin during ubiquitination, its regulatory role in adipogenesis has not received adequate attention. In this review, we summarize the E3s' regulation and modification targets in animal adipogenesis, explain the regulatory mechanisms in lipogenic-related pathways, and further analyze the existing positive results to provide research directions of guiding significance for further studies on the regulatory mechanisms of E3s in animal adipogenesis.

Adaptive resistance is not responsible for long-term drug resistance in a cellular model of triple negative breast cancer

Resistance to cancer therapeutics represents a leading cause of mortality and is particularly important in cancers, such as triple negative breast cancer, for which no targeted therapy is available, as these are only treated with traditional chemotherapeutics. Cancer, as well as bacterial, drug resistance can be intrinsic, acquired or adaptive. Adaptive cancer drug resistance is gaining attention as a mechanism for the generation of long-term drug resistance as is the case with bacterial antibiotic resistance. We have used a cellular model of triple negative breast cancer (CAL51) and its drug resistance derivative (CALDOX) to gain insight into genome-wide expression changes associated with long-term doxorubicin (a widely used anthracycline for cancer treatment) resistance and doxorubicin-induced stress. Previous work indicates that both naïve and resistance cells have a functional p53-p21 axis controlling cell cycle at G1, although this is not a driver for drug resistance, but down-regulation of TOP2A (topoisomerase IIα). As expected, CALDOX cells have a signature characterized, in addition to down-regulation of TOP2A, by genes and pathways associated with drug resistance, metastasis and stemness. Both CAL51 and CALDOX stress signatures share 12 common genes (TRIM22, FAS, SPATA18, SULF2, CDKN1A, GDF15, MYO6, CXCL5, CROT, EPPK1, ZMAT3 and CD44), with roles in the above-mentioned pathways, indicating that these cells have similar functional responses to doxorubicin relaying on the p53 control of apoptosis. Eight genes are shared by both drug stress signatures (in CAL51 and CALDOX cells) and CALDOX resistant cells (FAS, SULF2, CDKN1A, CXCL5, CD44, SPATA18, TRIM22 and CROT), many of them targets of p53. This corroborates experimental data indicating that CALDOX cells, even in the absence of drug, have activated, at least partially, the p53-p21 axis and DNA damage response. Although this eight-gene signature might be an indicator of adaptive resistance, as this transient phenomenon due to short-term stress may not revert to its original state upon withdrawal of the stressor, previous experimental data indicates that the p53-p21 axis is not responsible for doxorubicin resistance. Importantly, TOP2A is not responsive to doxorubicin treatment and thus absent in both drug stress signatures. This indicates that during the generation of doxorubicin resistance, cells acquire genetic changes likely to be random, leading to down regulation of TOP2A, but selected during the generation of cells due to the presence of drug in the culture medium. This poses a considerable constraint for the development of strategies aimed at avoiding the emergence of drug resistance in the clinic.

AP-2δ Is the Most Relevant Target of AP-2 Family-Focused Cancer Therapy and Affects Genome Organization

Formerly hailed as "undruggable" proteins, transcription factors (TFs) are now under investigation for targeted therapy. In cancer, this may alter, inter alia, immune evasion or replicative immortality, which are implicated in genome organization, a process that accompanies multi-step tumorigenesis and which frequently develops in a non-random manner. Still, targeting-related research on some TFs is scarce, e.g., among AP-2 proteins, which are known for their altered functionality in cancer and prognostic importance. Using public repositories, bioinformatics tools, and RNA-seq data, the present study examined the ligandability of all AP-2 members, selecting the best one, which was investigated in terms of mutations, targets, co-activators, correlated genes, and impact on genome organization. AP-2 proteins were found to have the conserved "TF_AP-2" domain, but manifested different binding characteristics and evolution. Among them, AP-2δ has not only the highest number of post-translational modifications and extended strands but also contains a specific histidine-rich region and cleft that can receive a ligand. Uterine, colon, lung, and stomach tumors are most susceptible to AP-2δ mutations, which also co-depend with cancer hallmark genes and drug targets. Considering AP-2δ targets, some of them were located proximally in the spatial genome or served as co-factors of the genes regulated by AP-2δ. Correlation and functional analyses suggested that AP-2δ affects various processes, including genome organization, via its targets; this has been eventually verified in lung adenocarcinoma using expression and immunohistochemistry data of chromosomal conformation-related genes. In conclusion, AP-2δ affects chromosomal conformation and is the most appropriate target for cancer therapy focused on the AP-2 family.

FOXC1‑mediated TRIM22 regulates the excessive proliferation and inflammation of fibroblast‑like synoviocytes in rheumatoid arthritis via NF‑κB signaling pathway

Rheumatoid arthritis (RA) is a common systemic autoimmune disorder of unknown etiology, which threatens public health. The regulatory role of tripartite motif-containing 22 (TRIM22) has been reported in multiple types of cancers and disease, but not in RA. The aim of the present study was therefore to elucidate the potential roles and underlying mechanisms of TRIM22 in fibroblast-like synoviocytes (FLSs) in RA. The Gene Expression Omnibus database was used to examine TRIM22 mRNA expression levels in synovial tissue samples of patients with RA and healthy controls. TRIM22 and forkhead box C1 (FOXC1) mRNA and protein expression levels in normal FLSs and RA-FLSs were assessed using reverse transcription-quantitative PCR (RT-qPCR) and western blotting, respectively. The Cell Counting Kit-8 assay was used to assess cell proliferation. Cell apoptosis was analyzed using flow cytometry. The migratory and invasive abilities of RA-FLSs were assessed using Transwell assays. Western blotting was used to analyze the protein expression levels of apoptosis-related factors, MMP2, MMP9 and NF-κB signaling pathway-related proteins. Inflammatory factors levels were assessed via ELISA and RT-qPCR. Furthermore, the JASPAR database, chromatin immunoprecipitation and the dual-luciferase reporter assays were used to determine the interaction between FOXC1 and the TRIM22 promoter. The results of the present study demonstrated that TRIM22 expression levels were significantly elevated in the synovial tissue samples of patients with RA and RA-FLSs. Moreover, FOXC1 was also significantly overexpressed in RA-FLSs. TRIM22 knockdown significantly reduced cell proliferation, migration, invasion and the inflammatory response, whereas cell apoptosis was significantly increased. Furthermore, the results demonstrated that FOXC1 may have positively mediated TRIM22 expression via binding to the TRIM22 promoter. Moreover, FOXC1 overexpression significantly reversed the outcome of TRIM22 knockdown on the proliferation, apoptosis, migration, invasion and inflammation of RA-FLSs. FOXC1 overexpression also significantly reversed the inactivation of the NF-κB signaling pathway caused by TRIM22 knockdown. In summary, the present study demonstrated that TRIM22 was potentially activated via FOXC1, which contributed to the progression of RA via the NF-κB signaling pathway.

TRIM22 actives PI3K/Akt/mTOR pathway to promote Psoriasis through enhancing cell proliferation and inflammation and inhibiting autophagy

OBJECTIVE

To reveal the function and underlying mechanism of Tri-domain protein 22 (TRIM22) in psoriasis.

MEHTODS

M5 cytokines were applied in HaCat cells to mimic psoriasis in vitro. The TRIM22-silencing virus were established to knockdown of TRIM22 in HaCat cells. Western blot and/or real-time PCR were used to detect the expression of TRIM22, KRT1, KRT6, p-P65, P65, LC3, Beclin 1, P62, p-PI3K, PI3K, p-Akt, Akt, p-mTOR and mTOR. ELISA kits were applied to assess levels of TNF-α, IL-1β, IL-18 and HMGB1.

RESULTS

TRIM22 expression levels were upregulated in M5-treated HaCat cells. M5 treatment enhanced cell proliferation and inflammation, and inhibited autophagy in HaCat cells which were effectively reversed by TRIM22 deficiency. Activation of PI3K/Akt/mTOR pathway is an essential promoter of cell proliferation and inflammation, and inhibitor of autophagy in psoriasis. TRIM22 deficiency blocked M5-induced activation of PI3K/Akt/mTOR pathway in HaCat cells.

CONCLUSIONS

TRIM22 facilitates cell proliferation and inflammation, and suppresses autophagy in M5-treated HaCat cells through activating PI3K/Akt/mTOR pathway, and inhibition of TRIM22 can be a novel potential treatment for psoriasis.

Cancer-Associated Dysregulation of Sumo Regulators: Proteases and Ligases

SUMOylation is a post-translational modification that has emerged in recent decades as a mechanism involved in controlling diverse physiological processes and that is essential in vertebrates. The SUMO pathway is regulated by several enzymes, proteases and ligases being the main actors involved in the control of sumoylation of specific targets. Dysregulation of the expression, localization and function of these enzymes produces physiological changes that can lead to the appearance of different types of cancer, depending on the enzymes and target proteins involved. Among the most studied proteases and ligases, those of the SENP and PIAS families stand out, respectively. While the proteases involved in this pathway have specific SUMO activity, the ligases may have additional functions unrelated to sumoylation, which makes it more difficult to study their SUMO-associated role in cancer process. In this review we update the knowledge and advances in relation to the impact of dysregulation of SUMO proteases and ligases in cancer initiation and progression.

The Role of SUMO E3 Ligases in Signaling Pathway of Cancer Cells

Small ubiquitin-like modifier (SUMO)ylation is a reversible post-translational modification that plays a crucial role in numerous aspects of cell physiology, including cell cycle regulation, DNA damage repair, and protein trafficking and turnover, which are of importance for cell homeostasis. Mechanistically, SUMOylation is a sequential multi-enzymatic process where SUMO E3 ligases recruit substrates and accelerate the transfer of SUMO onto targets, modulating their interactions, localization, activity, or stability. Accumulating evidence highlights the critical role of dysregulated SUMO E3 ligases in processes associated with the occurrence and development of cancers. In the present review, we summarize the SUMO E3 ligases, in particular, the novel ones recently identified, and discuss their regulatory roles in cancer pathogenesis.

TRIM22 inhibits the proliferation of gastric cancer cells through the Smad2 protein

TRIM22 is involved in tumorigenesis and development, but its mechanism is not clear. In this study, we investigated the expression and biological role of TRIM22 in gastric cancer. We found that TRIM22 mRNA and protein expression was abnormally low in gastric cancer tissues and cells and correlated with tumor size and depth of invasion. Overexpression of TRIM22 significantly inhibited the proliferation, colony formation, and migration of gastric cancer cells and downregulated the expression of HSPA6. However, the HSPA6-siRNA complementation test showed that TRIM22 did not regulate cell proliferation through HSPA6. Furthermore, overexpression of TRIM22 downregulated the phosphorylation of Smad2 and Smad3. In addition, TRIM22 directly binds to Smad2, and overexpression of Smad2 can reverse the inhibition of cell proliferation and migration induced by TRIM22. In vivo, overexpression of TRIM22 significantly inhibited the growth of subcutaneous xenografts in nude mice. Our study indicates that TRIM22 has an important role in the development of gastric cancer and may inhibit the proliferation of gastric cancer cells through Smad2.

Transcriptomic profiling of three-dimensional cholangiocyte spheroids long term exposed to repetitive Clonorchis sinensis excretory-secretory products

Background

Biliary tract infection with the carcinogenic human liver fluke, Clonorchis sinensis, provokes chronic inflammation, epithelial hyperplasia, periductal fibrosis, and even cholangiocarcinoma. Complications are proportional to the intensity and duration of the infection. In addition to mechanical irritation of the biliary epithelia from worms, their excretory-secretory products (ESPs) cause chemical irritation, which leads to inflammation, proliferation, and free radical generation.

Methods

A three-dimensional in vitro cholangiocyte spheroid culture model was established, followed by ESP treatment. This allowed us to examine the intrinsic pathological mechanisms of clonorchiasis via the imitation of prolonged and repetitive in vivo infection.

Results

Microarray and RNA-Seq analysis revealed that ESP-treated cholangiocyte H69 spheroids displayed global changes in gene expression compared to untreated spheroids. In ESP-treated H69 spheroids, 185 and 63 probes were found to be significantly upregulated and downregulated, respectively, corresponding to 209 genes (p < 0.01, fold change > 2). RNA-Seq was performed for the validation of the microarray results, and the gene expression patterns in both transcriptome platforms were well matched for 209 significant genes. Gene ontology analysis demonstrated that differentially expressed genes were mainly classified into immune system processes, the extracellular region, and the extracellular matrix. Among the upregulated genes, four genes (XAF1, TRIM22, CXCL10, and BST2) were selected for confirmation using quantitative RT-PCR, resulting in 100% similar expression patterns in microarray and RNA-Seq.

Conclusions

These findings broaden our understanding of the pathological pathways of liver fluke-associated hepatobiliary disorders and suggest a novel therapeutic strategy for this infectious cancer.

Graphic abstract

Supplementary Information

The online version contains supplementary material available at 10.1186/s13071-021-04717-2.

TRIM Proteins in Colorectal Cancer: TRIM8 as a Promising Therapeutic Target in Chemo Resistance

Colorectal cancer (CRC) represents one of the most widespread forms of cancer in the population and, as all malignant tumors, often develops resistance to chemotherapies with consequent tumor growth and spreading leading to the patient’s premature death. For this reason, a great challenge is to identify new therapeutic targets, able to restore the drugs sensitivity of cancer cells. In this review, we discuss the role of TRIpartite Motifs (TRIM) proteins in cancers and in CRC chemoresistance, focusing on the tumor-suppressor role of TRIM8 protein in the reactivation of the CRC cells sensitivity to drugs currently used in the clinical practice. Since the restoration of TRIM8 protein levels in CRC cells recovers chemotherapy response, it may represent a new promising therapeutic target in the treatment of CRC.

TRIM proteins in lung cancer: Mechanisms, biomarkers and therapeutic targets

The tripartite motif (TRIM) family is defined by the presence of a Really Interesting New Gene (RING) domain, one or two B-box motifs and a coiled-coil region. TRIM proteins play key roles in many biological processes, including innate immunity, tumorigenesis, cell differentiation and ontogenetic development. Alterations in TRIM gene and protein levels frequently emerge in a wide range of tumors and affect tumor progression. As canonical E3 ubiquitin ligases, TRIM proteins participate in ubiquitin-dependent proteolysis of prominent components of the p53, NF-κB and PI3K/AKT signaling pathways. The occurrence of ubiquitylation events induced by TRIM proteins sustains internal balance between tumor suppressive and tumor promoting genes. In this review, we summarized the diverse mechanism of TRIM proteins responsible for the most common malignancy, lung cancer. Furthermore, we also discussed recent progress in both the diagnosis and therapeutics of tumors contributed by TRIM proteins.

Long Noncoding RNA LINC01207 Promotes Colon Cancer Cell Proliferation and Invasion by Regulating miR-3125/TRIM22 Axis

Increasing study has validated that long noncoding RNAs (lncRNAs) are involved in the growth and metastasis of colon cancer. LINC01207 has been reported to play vital roles in certain types of cancer, while the precise function of LINC01207 in the progression of colon cancer remains unclear. The objective of this study was to investigate the effect of LINC01207 on the growth and metastasis of colon cancer cells and to explore the underlying mechanism. We found that the expression of LINC01207 was significantly upregulated in colon adenocarcinoma tissues compared with normal tissues by the GEPIA database. Notably, silencing of LINC01207 significantly suppressed the proliferation, migration, and invasion abilities of SW480 and HT-29 cells. Mechanistically, our data demonstrated that LINC01207 could sponge miR-3125 in colon cancer cells. Moreover, miR-3125 could directly target TRIM22 and negatively regulate its expression. Rescue assays revealed that miR-3125 inhibitor or TRIM22 overexpression significantly reversed the repressive role of LINC01207 knockdown in colon cancer cell proliferation and invasion. In conclusion, LINC01207 exerts an oncogenic role in the progression of colon cancer by absorbing miR-3125 to modulating TRIM22 expression.

Alternative splicing of LSD1+8a in neuroendocrine prostate cancer is mediated by SRRM4

Neuroendocrine prostate cancer (NEPC) is the most virulent form of prostate cancer. Importantly, our recent work examining metastatic biopsy samples demonstrates NEPC is increasing in frequency. In contrast to prostate adenocarcinomas that express a luminal gene expression program, NEPC tumors express a neuronal gene expression program. Despite this distinction, the diagnosis of NEPC is often challenging, demonstrating an urgent need to identify new biomarkers and therapeutic targets. Our prior work demonstrated that the histone demethylase LSD1 (KDM1A) is important for survival of prostate adenocarcinomas, but little was known about LSD1's role in NEPC. Recently, a neural-specific transcript variant of LSD1-LSD1+8a-was discovered and demonstrated to activate neuronal gene expression in neural cells. The splicing factor SRRM4 was previously shown to promote LSD1+8a splicing in neuronal cells, and SRRM4 promotes NEPC differentiation and cell survival. Therefore, we sought to determine if LSD1+8a might play a role in NEPC and whether LSD1+8a splicing was linked to SRRM4. To investigate a potential role for LSD1+8a in NEPC, we examined a panel of prostate adenocarcinoma and NEPC patient-derived xenografts and metastatic biopsies. LSD1+8a was expressed exclusively in NEPC samples and correlated significantly with elevated expression of SRRM4. Using SRRM4-overexpressing cell lines, we determined that SRRM4 mediates alternative splicing of LSD1+8a. Finally, using gain of function studies, we confirmed that LSD1+8a and SRRM4 co-regulate target genes distinct from canonical LSD1. Our findings suggest further study of the interplay between SRRM4 and LSD1+8a and mechanisms by which LSD1+8a regulates gene expression in NEPC is warranted.

The Tripartite Nexus: Autophagy, Cancer, and Tripartite Motif-Containing Protein Family Members

Autophagy is a cellular degradative process that has multiple important actions in cancer. Autophagy modulation is under consideration as a promising new approach to cancer therapy. However, complete autophagy dysregulation is likely to have substantial undesirable side effects. Thus, more targeted approaches to autophagy modulation may prove clinically beneficial. One potential avenue to achieving this goal is to focus on the actions of tripartite motif-containing protein family members (TRIMs). TRIMs have key roles in an array of cellular processes, and their dysregulation has been extensively linked to cancer risk and prognosis. As detailed here, emerging data shows that TRIMs can play important yet context-dependent roles in controlling autophagy and in the selective targeting of autophagic substrates. This review covers how the autophagy-related actions of TRIM proteins contribute to cancer and the possibility of targeting TRIM-directed autophagy in cancer therapy.

TRIM22 inhibits endometrial cancer progression through the NOD2/NF‑κB signaling pathway and confers a favorable prognosis

Endometrial cancer (EnC) is a malignant gynecological tumor commonly observed in developed countries, specifically among post‑menopausal women. Although numerous patients with EnC receive promising prognoses, those with advanced or metastatic disease often have a poor prognosis and an impaired quality of life. Tripartite motif‑containing 22 (TRIM22) has been confirmed to play many crucial roles in different biological processes, from inflammatory to tumorigenesis. However, the multifaceted roles of TRIM22 in EnC remain uncharacterized. Herein, comparing normal endometrial tissues with tumor tissues obtained from patients, it was concluded that TRIM22 expression was decreased in tumor tissues. However, the overexpression of TRIM22 served to inhibit the migratory, invasive, proliferative and cell cycle activity of EnC cells. Moreover, the knockdown of TRIM22 increased the migratory, invasive, and proliferative activity of the EnC cells. Furthermore, it was found that TRIM22 effectively suppressed EnC progression through the nucleotide binding oligomerization domain containing 2 (NOD2)/nuclear factor (NF)‑κB pathway. The data also demonstrated that TRIM22 functions as an inhibitor of EnC tumor xenograft growth in vivo. Overall, the findings of the present study define a novel regulatory role for TRIM22 in EnC progression. Moreover, TRIM22 may serve as an important prognostic predictor for EnC.

FOXO3/TRIM22 axis abated the antitumor effect of gemcitabine in non-small cell lung cancer via autophagy induction

Background

Non-small cell lung cancer (NSCLC) accounts for more than 80% of the total lung cancer and gemcitabine (GEM)-based chemotherapy is the first-line therapeutic approach for NSCLC treatment. Owing to acquired chemo-resistance, the prognosis of NSCLC patients receiving GEM treatment is still poor.

Methods

Dysregulation of mRNAs in GEM-resistant (GR) NSCLC cells comparing to parental cells were profiled by analyzing GSEA6914 datasets from GEO database. Additionally, qRT-PCR were performed on clinically collected patient serum samples and transplanted tumor tissues and GEM-resistant (GR)/sensitive (GS) cell lines. In order to explore the functional role of tripartite motif protein 22 (TRIM22), gain and loss-of-function cell models were constructed in A549 and A549/GR respectively. MTT and Annexin V-FITC/propidium iodide (PI) staining assay were carried out to access the response to GEM of A549 and A549/GR cells. Observation of RFP-LC3 puncta and western blot detection of autophagy markers were used to evaluate autophagy. Bi-luciferase reporter assay was used to confirm the transcriptional regulatory relationship. Rescue experiments were carried out to confirm the FOXO3/TRIM22 regulatory axis in GEM susceptibility.

Results

TRIM22 was significantly upregulated in GR patient serum samples, transplanted tumor tissues and NSCLC cells which was negatively transcriptional regulated by FOXO3. TRIM22 overexpression attenuated the sensitivity of A549 to GEM and its depletion promoted the sensitivity of A549/GR to GEM. Additionally, TRIM22 promoted GEM-induced pro-survival autophagy to protected NSCLC cells from apoptosis.

Conclusions

TRIM22 was significantly upregulated in GR lung adenocarcinoma cell line A549 which is negatively transcriptional regulated by FOXO3. Due to the enhancement of pro-survival autophagy induced by TRIM22, the A549 cells became less sensitive to GEM. This study may provide a basis for screening target of liquid biopsy for predicting GEM sensitivity in NSCLC.

The effects and mechanisms of a biosynthetic ginsenoside 3β,12β-Di-O-Glc-PPD on non-small cell lung cancer

Background

A biosynthetic ginsenoside, 3-O-β-D-glucopyranosyl-12-O-β-D-glucopyranosyl-dammar-24-ene-3β, 12β, 20S-triol (C₃C₁₂PPD), showed antitumor activity against many tumor cells in vitro, especially had better anti-lung cancer activity than Rg3 in vitro and in vivo. However, the effects and molecular mechanisms of C₃C₁₂PPD on non-small cell lung cancer (NSCLC) remain unclear. According to previous studies, we hypothesized ginsenoside C₃C₁₂PPD could inhibit the tumor growth of NSCLC by targeting proliferation, migration and angiogenesis.

Methods

A thiazolyl blue tetrazolium bromide assay (MTT) was performed to evaluate cell viability. Additionally, Transwell and tube formation assays were conducted to analyze cell migration and angiogenesis. The Lewis and A549 tumor xenograft experiments were also performed to investigate the effects of C₃C₁₂PPD on tumor growth in vivo, Western blotting and IHC assay were performed to analyze protein expression.

Results

C₃C₁₂PPD could effectively inhibit the proliferation and migration of lung cancer cells, and tube formation of EA.hy926 cell. Ginsenoside C₃C₁₂PPD suppressed Lewis and A549 tumor growth in vivo without obvious side effects on body weight and the hematology index. In addition, the Western blot analysis revealed that the effects of C₃C₁₂PPD on lung cancer were mediated by inhibiting Raf/MEK/ERK, AKT/mTOR and AKT/GSK-3β/β-Catenin signaling pathways. Finally, C₃C₁₂PPD could significantly inhibit the proliferation index and vessel number in Lewis xenograft tumors analyzed by IHC.

Conclusion

The results of the present study suggest that ginsenoside C₃C₁₂PPD may serve as a potential therapeutic candidate compound against NSCLC.

Suppression of epidermal growth factor receptor-mediated β-catenin nuclear accumulation enhances the anti-tumor activity of phosphoinositide 3-kinase inhibitor in breast cancer

Phosphoinositide 3-kinase (PI3K) signaling is frequently deregulated in breast cancer and plays a critical role in tumor progression. However, resistance to PI3K inhibitors in breast cancer has emerged, which is due to the enhanced β-catenin nuclear accumulation. Until now, the mechanisms underlying PI3K inhibition-induced β-catenin nuclear accumulation remains largely unknown. In the present study, we found inhibition of PI3K with LY294002 promoted β-catenin nuclear accumulation in MCF-7 and MDA-MB-231 breast cancer cells. Combining PI3K inhibitor LY294002 with XAV-939, an inhibitor against β-catenin nuclear accumulation, produced an additive anti-proliferation effect against breast cancer cells. Subsequent experiments suggested β-catenin nuclear accumulation induced by PI3K inhibition depended on the feedback activation of epidermal growth factor receptor (EGFR) signaling pathway in breast cancer cells. Inhibition of EGFR phosphorylation with Gefitinib enhanced anti-proliferation effect of PI3K inhibitor LY294002 in MCF-7 and MDA-MB-231 cells. Taken together, our findings may elucidate a possible mechanism explaining the poor outcome of PI3K inhibitors in breast cancer treatment.

TIMM50 promotes tumor progression via ERK signaling and predicts poor prognosis of non-small cell lung cancer patients

TIMM50 (Translocase of the inner mitochondrial membrane 50), also called TIM50, plays an essential role in mitochondrial membrane transportation. The existing literature suggests that TIMM50 may perform as an oncogenetic protein in breast cancer. However, the molecular mechanism, especially in human non-small cell lung cancer (NSCLC), is uncertain to date. In the present study, using immunohistochemistry, we found that TIMM50 expression significantly correlated with larger tumor size (P = 0.049), advanced TNM stage (P = 0.001), positive regional lymph node metastasis (P = 0.007), and poor overall survival (P = 0.001). Proliferation and invasion assay showed that TIMM50 dramatically promoted the ability of proliferation and invasion of NSCLC cells. Subsequent Western blotting results revealed that TIMM50 enhanced the expression of Cyclin D1 and Snail, and inhibited the expression of E-cadherin. Moreover, TIMM50 facilitated the expression of phosphorylated ERK and P90RSK. Incorporation of ERK inhibitor counteracted the upregulating expression of CyclinD1, and Snail, and downregulating expression of E-cadherin expression induced by TIMM50 overexpression. In conclusion, our data indicated that TIMM50 facilitated tumor proliferation and invasion of NSCLC through enhancing phosphorylation of its downstream ERK/P90RSK signaling pathway. We speculated that TIMM50 might be a useful prognosis marker of NSCLC patients.

TRIM37 targets AKT in the growth of lung cancer cells

Background

TRIM37 is an ubiquitin E3 ligase. Growing evidence has demonstrated the high value of TRIM37 as a potential biomarker for diagnosis of certain cancers. However, the biological function of TRIM37 in lung cancer is still unknown.

Materials and methods

In order to gain a deep insight into the function of TRIM37 in lung cancer cells, in the present study lentiviral vector was used to mediate RNA interference and overexpression of TRIM37 in lung cancer cells (H292, H358, and H1299). In addition, a specific AKT inhibitor LY294002 was utilized to examine the correlation between the expression of TRIM37 and AKT.

Results

TRIM37 acts as a positive regulator of cell proliferation in lung cancer cells. Moreover, cell apoptosis analyses showed the antiapoptosis function of TRIM37, which was mainly dependent on the regulation of BCL2 and BAX. Our results also indicated that AKT might be a target of TRIM37 in lung cancer cells.

Conclusion

This research not only helps in understanding the molecular mechanisms of TRIM37 in detail but also provides evidence to develop novel biomarkers for lung cancer diagnosis.

PI3K expression predicts overall survival in lung adenocarcinoma

BACKGROUND

Phosphoinositide 3-kinase (PI3K)/phosphorylated PI3K (p-PI3K) is considered a hallmark in tumor initiation and progression, but its prognostic value in non-small cell lung cancer (NSCLC) remains controversial.

METHODS

In the present study, we included 118 NSCLC tissue samples and 13 adjacent normal lung tissue specimens. Immunohistochemical staining was applied to test PI3K/p-PI3K expression. Pearson Chi-squared test and Kaplan-Meier curve were conducted to analyze its correlation with both clinicopathological features and prognosis in NSCLC patients.

RESULTS

PI3K/p-PI3K expression in lung cancer tissue differed significantly from that of normal lung tissue (P < 0.001). M stage was significantly correlated to PI3K expression (P = 0.037), but no significant association was found between p-PI3K expression and clinical characteristics. Neither PI3K nor p-PI3K were correlated to overall survival of NSCLC patients (P = 0.105 and P = 0.190, respectively). However, it was found in subgroup analysis that lung adenocarcinoma patients with positive PI3K expression had a favorable survival (P = 0.043). Notably, this correlation was determined invalid in subsequent multivariate analysis (P = 0.052).

CONCLUSIONS

PI3K could predict the overall survival of lung adenocarcinoma patients, but failed to be an independent prognostic predictor.

Retracted Article: TRIM22 functions as an oncogene in gliomas through regulating the Wnt/β-catenin signaling pathway

The tripartite motif-containing (TRIM) family is a group of proteins that are implicated in a plethora of pathological conditions. TRIM22 has been found to be involved in various cancers; however, the role of TRIM22 in gliomas has not been reported. The present study aimed to evaluate the expression pattern of TRIM22 and its function in gliomas. TRIM22 expressions in glioma tissues and cell lines were measured by RT-PCR and western blot analysis. To knockdown TRIM22 by small hairpin RNAs (shTRIM22), the U118 cells were transfected with pLKO.1-shTRIM22 plasmid or pLKO.1 plasmid. Cell proliferation was measured using CCK-8 assay. Transwell assays were performed to evaluate the migration and invasion. The epithelial-mesenchymal transition (EMT) was assessed by detecting the expressions of E-cadherin, N-cadherin and vimentin with western blot analysis. A xenograft mouse model was established to evaluate the effect of TRIM22 silencing on tumor growth in vivo. The expressions of β-catenin, cyclin D1, and c-Myc were analyzed by western blot analysis. TRIM22 was significantly overexpressed in glioma tissues and cell lines. In vitro studies demonstrated that TRIM22 knockdown inhibited cell proliferation, migration, and invasion. Additionally, TRIM22 silencing increased the expressions of E-cadherin, and decreased the expressions of N-cadherin and vimentin. Nude mouse xenograft assay showed that TRIM22 silencing inhibited tumor growth in vivo. Furthermore, silencing of TRIM22 inhibited the activation of the Wnt/β-catenin pathway. Treatment with LiCl, an activator of the Wnt/β-catenin pathway, attenuated the effects of shTRIM22 on U118 cells. Silencing of TRIM22 inhibited proliferation, migration and invasion, as well as repressing the EMT process in glioma cells. The Wnt/β-catenin pathway was involved in the effect of TRIM22.

Astragaloside IV Inhibits the Progression of Non-Small Cell Lung Cancer Through the Akt/GSK-3β/β-Catenin Pathway

Astragaloside IV (AS-IV) is an active ingredient in Astragalus membranaceus and is involved in various biological processes, such as regulating the immune system, and counteracting inflammation and malignancy. The aim of this study was to explore the effect of AS-IV on non-small cell lung cancer (NSCLC) cells. Cell counting kit (CCK)-8 assay and flow cytometry were performed to investigate cell survival and cell death, and Western blotting was performed to assess protein expression. We found that AS-IV inhibited the migration and proliferation of NSCLC cells and caused a noticeable increase in cell death. Furthermore, the expression of Bax, a marker of cell death, was increased, whereas the expression of Bcl-2, an antiapoptotic protein, was reduced. AS-IV also promoted cleavage of caspase-3, another indication of apoptosis. Finally, the Akt/GSK-3β/β-catenin axis was suppressed in response to AS-IV. Taken together, these findings provide evidence that AS-IV inhibits NSCLC development via inhibition of the Akt/GSK-3β/β-catenin signaling axis. We therefore propose that AS-IV represents a promising novel agent for the treatment of NSCLC.

TRIM22 knockdown suppresses chronic myeloid leukemia via inhibiting PI3K/Akt/mTOR signaling pathway

Tripartite motif-containing 22 (TRIM22) is reported to participate in numerous cellular activities. Recent studies confirm that TRIM22 is a target gene for P53, and inhibits clonogenic growth of leukemic U-937 cells. The current study aims to discover the effect of TRIM22 in progression of human chronic myeloid leukemia (CML) and explore the related mechanism. TRIM22 was knocked down by siRNA transfection in CML cell K562. We observed that TRIM22 knockdown decreased proliferation and invasion in K562 cells. TRIM22 knockdown significantly induced cell cycle arrest by regulating the level of CDK4, Cyclin D1, P70S6K, and P53 in K562 cell. Moreover, loss of TRIM22 also promoted apoptosis through modulation of Bcl-2, Bax and active Caspase 3 in K562 cell. Furthermore, we demonstrated that TRIM22 knockdown inhibited the activation of PI3K/Akt/mTOR pathway by decreasing the level of the phosphorylated form p-Akt and p-mTOR in K562 cell. In conclusion, loss of TRIM22 suppresses the progression and invasion of CML through regulation of PI3K/Akt/mTOR pathway, suggesting that TRIM22 might be as a potential target for the treatment strategy of CML.

Matrine inhibits the proliferation and migration of lung cancer cells through regulation of the protein kinase B/glycogen synthase kinase-3β signaling pathways

Lung cancer is the leading cause of cancer-related mortality worldwide. Despite recent advances in treatment, lung cancer remains an incurable disease. Matrine, an active compound isolated from Sophora flavescens, has been demonstrated to inhibit proliferation and induce apoptosis of tumor cells. However, the protective effects and molecular mechanisms of matrine in lung cancer remain elusive. In the present study, the lung cancer cells H1299 and A549 were used to investigate how matrine affects the proliferation, migration and apoptosis of lung cancer cells in vitro. It was demonstrated that matrine is able to significantly suppress the proliferation and colony formation of lung cancer cells in vitro. Using cell apoptosis analysis, wound-healing and Transwell assays, it was demonstrated that matrine induced cellular apoptosis and inhibited the migration of lung cancer cells. Further experiments revealed that matrine significantly suppressed the phosphorylation of protein kinase B (Akt) and glycogen synthase kinase-3β (GSK-3β). The present results suggested that matrine inhibits lung cancer cell proliferation, and induces cell apoptosis by suppressing the Akt/GSK-3β signaling pathway, which demonstrated that matrine may have therapeutic potential for lung cancer.

Mycoplasma hyorhinis reduces sensitivity of human lung carcinoma cells to Nutlin-3 and promotes their malignant phenotype

PURPOSE

MDM2 inhibitors are promising anticancer agents that induce cell cycle arrest and tumor cells death via p53 reactivation. We examined the influence of Mycoplasma hyorhinis infection on sensitivity of human lung carcinoma cells NCI-H292 to MDM2 inhibitor Nutlin-3. In order to unveil possible mechanisms underlying the revealed effect, we investigated gene expression changes and signal transduction networks activated in NCI-H292 cells in response to mycoplasma infection.

METHODS

Sensitivity of NCI-Н292 cells to Nutlin-3 was estimated by resazurin-based cell viability assay. Genome-wide transcriptional profiles of NCI-H292 and NCI-Н292^Myc.h cell lines were determined using Illumina Human HT-12 v3 Expression BeadChip. Search for key transcription factors and key node molecules was performed using the geneXplain platform. Ability for anchorage-independent growth was tested by soft agar colony formation assay.

RESULTS

NCI-Н292^Myc.h cells were shown to be 1.5- and 5.2-fold more resistant to killing by Nutlin-3 at concentrations of 15 and 30 µM than uninfected NCI-Н292 cells (P < 0.05 and P < 0.001, respectively). Transcriptome analysis revealed differential expression of multiple genes involved in cancer progression and metastasis as well as epithelial-mesenchymal transition (EMT). Moreover, we have shown experimentally that NCI-Н292^Myc.h cells were more capable of growing and dividing without binding to a substrate. The most likely mechanism explaining the observed changes was found to be TLR4- and IL-1b-mediated activation of NF-κB pathway.

CONCLUSIONS

Our results provide evidence that mycoplasma infection is an important factor modulating the effect of MDM2 inhibitors on cancer cells and is able to induce EMT-related changes.

Identification of key pathways and genes in response to trastuzumab treatment in breast cancer using bioinformatics analysis

Breast cancer (BC) is one of the leading causes of death among women worldwide. The gene expression profile GSE22358 was downloaded from the Gene Expression Omnibus (GEO) database, which included 154 operable early-stage breast cancer samples treated with neoadjuvant capecitabine plus docetaxel, with (34) or without trastuzumab (120), to identify gene signatures during trastuzumab treatment and uncover their potential mechanisms. The gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes pathway (KEGG) enrichment analyses were performed, and a protein–protein interaction (PPI) network of the differentially expressed genes (DEGs) was constructed by Cytoscape software. There were 2284 DEGs, including 1231 up-regulated genes enriched in DNA replication, protein N-linked glycosylation via asparagine, and response to toxic substances, while 1053 down-regulated genes were enriched in axon guidance, protein localization to plasma membrane, protein stabilization, and protein glycosylation. Eight hub genes were identified from the PPI network, including GSK3B, RAC1, PXN, ERBB2, HSP90AA1, FGF2, PIK3R1 and RAC2. Our experimental results showed that GSK3B was also highly expressed in breast cancer tissues and was associated with poor survival, as was β-catenin. In conclusion, the present study indicated that the identified DEGs and hub genes further our understanding of the molecular mechanisms underlying trastuzumab treatment in BC and highlighted GSK3B, which might be used as a molecular target for the treatment of BC.