High expression of RRM2 as an independent predictive factor of poor prognosis in patients with lung adenocarcinoma

Ribonucleotide-diphosphate reductase subunit M2 (RRM2) expression and colorectal cancer invasiveness: a potential prognostic biomarker

BACKGROUND

By evaluating serum Ribonucleotide-diphosphate Reductase subunit M2 (RRM2) levels and mRNA tissue expression, we aimed to investigate the potential role of RRM2 as a prognostic biomarker in Colorectal Cancer (CRC) patients.

METHODS

This descriptive-analytic cohort study was conducted on 50 newly diagnosed CRC patients (stage II, III). Real-time PCR determined the mRNA tissue expression of RRM2. Fifty healthy individuals who came to the hospital of Golestan University of Medical Sciences and Tehran University of Medical Sciences for routine check-ups were considered the control group. Serum RRM2 protein was measured using an ELISA method in the patient group before, one month, and three months after the surgery, and in the control group just on the day of a routine check-up. The tumor metastasis node (TMN) classification system and occurrence of liver metastasis were evaluated in CRC patients.

RESULTS

The RRM2 gene expression ratio and 95% confidence interval (CI) of the cancerous tissue was 6.56 times higher than the normal tissue (p < 0.001). Blood Sugar level (BS) (p < 0.001) and platelet level (PLT [range 0.004-499 × 103 /mm3]; p = 0.010) were higher in the case group compared with the control group significantly, while Mean Corpuscular Volume (MCV) was significantly lower in the case group (p = 0.015). Overall, the mean serum of RRM2 protein levels in patients was remarkably diminished from before surgery until three months after surgery (p < 0.001).

CONCLUSION

Serum RRM2 level and mRNA expression were significantly higher among CRC patients which could be considered a biomarker regarding CRC progression.

Genetic profile of ferroptosis in non-small cell lung carcinoma and pharmaceutical options for ferroptosis induction

Lung cancer (LC) is the leading cause of cancer-related deaths and the second most commonly diagnosed malignancy worldwide. Lung adenocarcinoma (LUAD) and lung squamous cell LC (LUSCC) are the most common subtypes of non-small cell LC (NSCLC). Early diagnosis of LC can be challenging due to a lack of biomarkers. The overall survival (OS) of patients with NSCLC is still poor despite the enormous efforts that have been made to develop novel treatments. Understanding fundamental molecular and genetic mechanisms is necessary to develop new therapeutic approaches for NSCLC. A recently identified type of programmed cell death known as ferroptosis is one potential approach. Ferroptosis causes oxidative damage and the death of cancerous cells by peroxidizing unsaturated phospholipids and accumulating reactive oxygen species (ROS) in an iron-dependent manner. Ferroptosis-related gene (FRG) signatures have recently been evaluated for their ability to predict patient OS and prognosis. These analyses show FRGs are involved in cancer progression, and may serve as promising biomarkers for tumor diagnosis and therapy. Moreover, we summarize the current pharmaceutical options of ferroptosis induction and their underlying molecular mechanism in LC. Therefore, this review aims to provide a comprehensive summary of FRG-based prognostic models, their associated metabolic and signaling pathways, and promising therapeutic options for ferroptosis induction in NSCLC.

The unique role of cuproptosis in the prognosis and treatment of rectum adenocarcinoma

Background

The incidence of digestive system cancers has increased significantly in recent years. Among these, rectum adenocarcinoma (READ), which exhibits distinct features compared to colon adenocarcinoma, has emerged as a unique subtype. Cuproptosis, a recently identified form of non-apoptotic programmed cell death, plays a pivotal role in tumorigenesis; however, its relationship with READ and its potential effect on prognosis remains poorly understood. This study innovatively explores the role of cuproptosis related genes (CRGs) in READ development and identifies potential therapeutic targets.

Methods

This study used consensus clustering to classify READ samples into three distinct clusters based on their survival status and enriched biological pathways. A cuproptosis-related score (CRS) was developed to examine the association between cuproptosis subtypes and patient prognosis. Immune infiltration was analyzed using multiple deconvolution algorithms to explore the immune landscape across different cuproptosis subtypes. A principal component analysis (PCA) was conducted to construct a prognostic score that reflects the clinical significance of cuproptosis in READ. Further investigations focused on lipoic acid synthetase (LIAS) as a key gene with prognostic implications for READ patients.

Results

Consensus clustering of the READ samples revealed three clusters with varying survival outcomes and distinct biological pathways. The CRS successfully predicted patient prognosis, and was found to be correlated with overall survival (OS) and tumor characteristics. The immune infiltration analysis revealed significant differences in immune profiles across the subtypes, with certain subtypes exhibiting immunosuppressive characteristics. LIAS was identified as a favorable prognostic marker for READ patients, and thus could serve as a potential therapeutic target.

Conclusions

CRGs play a critical role in the development and prognosis of READ. The established CRS could serve as a valuable tool for predicting patient outcomes. Further, LIAS emerged as a potential therapeutic target. Our findings may provide new avenues for targeted cancer treatment in READ.

UBE2Q1 as a novel cancer biomarker for lung adenocarcinoma

PURPOSE

Ubiquitin-conjugating enzymes (E2s) participate in various tumor-promoting processes. UBE2Q1 is a member of the E2 family. This research aimed to detect the expression level of UBE2Q1 in human lung adenocarcinoma and to study its malignant biological function.

METHODS

Western blot, qRT-PCR and immunohistochemistry was used to measure the expression of UBE2Q1 in human lung adenocarcinoma tissues. The association between UBE2Q1 expression and clinic-pathological variables in 99 lung adenocarcinoma samples was analyzed by immunohistochemistry. In vitro experiment, establishing UBE2Q1 knockdown pattern, the markers of apoptosis, cell cycle and epithelial-mesenchymal transition (EMT) were analyzed by Western blot. CCK8, colony formation, Transwell and invasion assay analyzed the effect of UBE2Q1 knockdown on the proliferation, metastasis and invasion of lung cancer cells.

RESULTS

UBE2Q1 was overexpressed in lung adenocarcinoma, and the expression level of UBE2Q1 was related with TNM stage, tumor size, and lymph node metastasis. The high level of UBE2Q1 expression was also associated with poor survival and was an independent risk factor. In vitro, It was also confirmed that steady downregulation of UBE2Q1 could promote apoptosis, induce G2/M cell cycle arrest and regulate EMT. UBE2Q1 silencing dramatically reduce lung tumor cells proliferation, migration and invasion capacities.

CONCLUSIONS

UBE2Q1 may serve as a prognostic biomarker and a new therapeutic target of lung adenocarcinoma.

HELLS Knockdown Inhibits the Malignant Progression of Lung Adenocarcinoma Via Blocking Akt/CREB Pathway by Downregulating KIF11

Lung adenocarcinoma (LUAD) is a malignant tumor with the characteristics of progressive advancement and high mortality rate worldwide. We aimed to explore the role and mechanism of helicase Lymphoid-Specific (HELLS) in LUAD. Bioinformatics databases were applied to predict HELLS and kinesin family member (KIF)11 expression in LUAD tissues. The expressions of HELLS and KIF11 before and after HELLS knockdown were detected by RT-qPCR and western blot. After HELLS was knocked down, the proliferative, migratory, and invasive capabilities of A549 cells were evaluated. Cell apoptotic level was assessed using TUNEL. Western blot was employed to evaluate the expressions of Akt/CREB pathway-related proteins. The interaction between HELLS and KIF11 was analyzed using bioinformatics databases, and testified by Co-IP assay. Results revealed that HELLS and KIF11 expressions were significantly upregulated in LUAD cells and tissues. High HELLS and KIF11 expression was correlated with the poor prognosis of patients with LUAD. Additionally, HELLS knockdown suppressed the capabilities of LUAD cells to proliferate, migrate, and invade whereas promoted the cell apoptotic level. Moreover, HELLS could interact with KIF11 and had positive correlation with KIF11. Furthermore, KIF11 overexpression partially counteracted the impacts of HELLS knockdown on cell proliferative, migratory, invasive capabilities, and apoptotic level in LUAD cells. Besides, Akt/CREB pathway was blocked by HELLS silencing, which was restored by KIF11 overexpression. Collectively, HELLS knockdown blocked Akt/CREB pathway by downregulating KIF11 expression, thereby inhibiting LUAD cell proliferation, invasion, migration, and promoting apoptosis.

Significance of Ribonucleoside-diphosphate Reductase Subunit M2 in Lung Adenocarcinoma

INTRODUCTION

The Ribonucleoside-diphosphate Reductase subunit M2 (RRM2) is known to be overexpressed in various cancers, though its specific functional implications remain unclear. This aims to elucidate the role of RRM2 in the progression of Lung Adenocarcinoma (LUAD) by exploring its involvement and potential impact.

METHODS

RRM2 data were sourced from multiple databases to assess its diagnostic and prognostic significance in LUAD. We evaluated the association between RRM2 expression and immune cell infiltration, analyzed its function, and explored the effects of modulating RRM2 expression on LUAD cell characteristics through laboratory experiments.

RESULTS

RRM2 was significantly upregulated in LUAD tissues and cells compared to normal counterparts (p < 0.05), with rare genetic alterations noted (approximately 2%). This overexpression clearly distinguished LUAD from normal tissue (area under the curve (AUC): 0.963, 95% confidence intervals (CI): 0.946-0.981). Elevated RRM2 expression was significantly associated with adverse clinicopathological characteristics and poor prognosis in LUAD patients. Furthermore, a positive association was observed between RRM2 expression and immune cell infiltration. Pathway analysis revealed a critical connection between RRM2 and the cell cycle signaling pathway within LUAD. Targeting RRM2 inhibition effectively suppressed LUAD cell proliferation, migration, and invasion while promoting apoptosis. This intervention also modified the expression of several crucial proteins, including the downregulation of CDC25A, CDC25C, RAD1, Bcl-2, and PPM1D and the upregulation of TP53 and Bax (p < 0.05).

CONCLUSION

Our findings highlight the potential utility of RRM2 expression as a biomarker for diagnosing and predicting prognosis in LUAD, shedding new light on the role of RRM2 in this malignancy.

RRM2 Is a Putative Biomarker and Promotes Bladder Cancer Progression via PI3K/AKT/mTOR Pathway

Bladder cancer (BLCA) is the tenth most common cancer worldwide, characterized by its high recurrence and progression rates. Thus, identifying prognostic biomarkers and understanding its underlying mechanisms are imperative to enhance patient outcomes. In this study, we aimed to investigate the prognostic significance, expression, functional activity, and underlying mechanisms of RRM2 in BLCA. RRM2 expression and its association with pathological grading and survival were investigated in samples from TCGA dataset and BLCA tissue microarray. CCK8 assays, colony formation assays, wound healing, and transwell assays were performed to assess the role of RRM2 in BLCA cell proliferation and migration. Western blot was employed to investigate alterations in markers associated with epithelial-to-mesenchymal transition (EMT), apoptosis, and cell cycle regulation. Gene set enrichment analysis was performed to investigate the biological processes associated with RRM2, which were subsequently validated. The expression of RRM2 was significantly elevated in both BLCA tissues and cells. Our results also indicated a positive correlation between RRM2 expression and high tumor stage, high tumor grade, and poor survival. Knockdown of RRM2 inhibited cell proliferation and migration of BLCA. RRM2 knockdown significantly induced apoptosis and arrested the cell cycle at the G0/G1 phase. Opposite results were observed in the RRM2 overexpression cells. Additionally, our study demonstrates that RRM2 promotes BLCA progression by activating the PI3K/AKT/mTOR pathway. RRM2 is remarkably correlated with poor prognosis in BLCA and facilitate its progression via PI3K/AKT/mTOR pathway. It is suggested that RRM2 might become an effective prognostic biomarker and potential therapeutic target for BLCA.

Identification and prognostic analysis of metabolic genes associated with TP53 mutation in multiple myeloma

BACKGROUND

TP53 gene mutation is crucial in determining the prognosis of Multiple Myeloma (MM) patients. Understanding metabolic genes linked to TP53 mutation is vital for developing targeted therapies for these patients.

METHOD

We analyzed The Cancer Genome Atlas (TCGA) dataset to identify genes related to TP53 mutation and metabolism. Using univariate Cox regression and protein-protein interaction (PPI) analysis, we identified key genes. We categorized patients into high and low metabolism groups via non-negative matrix factorization (NMF) clustering, which led to the discovery of relevant differential genes. Integrating these with genes from the Gene Expression Omnibus (GEO) datasets and PPI interactions, we pinpointed crucial metabolic genes associated with TP53 mutation in MM. Additionally, we conducted prognostic analyses involving survival curves and receiver operating characteristic (ROC) charts.

RESULTS

Our study reveals that the metabolic gene ribonucleotide reductase M2 (RRM2), linked to TP53 mutation, correlates positively with the International Staging System (ISS) stage in MM patients and is an independent prognostic risk factor. In the TCGA dataset, among the 767 patients, the 35 MM patients with TP53 mutation generally had poor survival outcomes. Specifically, the patients with both TP53 mutation and high RRM2 expression had a 2-year survival rate of only 38.87%, whereas those with normal TP53 function and low RRM2 expression had a 2-year survival rate of 86.31% (p < 0.001).

CONCLUSION

RRM2 significantly impacts MM prognosis and is associated with TP53 mutation, presenting itself as a potential therapeutic target and prognostic marker for MM.

Small Nuclear Ribonucleoprotein Polypeptides B and B1 Promote Osteosarcoma Progression via Activating the Ataxia-Telangiectasia Mutated Signaling Pathway through Ribonucleotide Reductase Subunit M2

Osteosarcoma is a malignant bone tumor characterized by high metastatic potential and recurrence rates after therapy. The small nuclear ribonucleoprotein polypeptides B and B1 (SNRPB), core components of a spliceosome, exhibit up-regulation across several cancer types. However, the precise role of SNRPB in osteosarcoma progression remains poorly elucidated. Herein, SNRPB expression was explored in human osteosarcoma tissues and normal bone tissues by immunohistochemical staining, revealing a notable up-regulation of SNRPB in osteosarcoma, correlating with diminished survival rates. The in vitro loss-of-function experiments showed that SNRPB knockdown significantly suppressed the osteosarcoma cell proliferation and migration, as well as tubule formation of human umbilical vascular endothelial cells, while enhancing osteosarcoma cell apoptosis. Mechanistically, SNRPB promoted the transcription of ribonucleotide reductase subunit M2 via E2F transcription factor 1. Further rescue experiments indicated that ribonucleotide reductase subunit M2 was required for SNRPB-induced malignant behaviors in osteosarcoma. Additionally, the function of SNRPB in osteosarcoma cell growth and apoptosis was confirmed to be associated with ataxia-telangiectasia mutated (ATM) signaling pathway activation. In conclusion, these findings provide initial insights into the underlying mechanisms governing SNRPB-induced osteosarcoma progression, and we propose SNRPB as a novel therapeutic target in osteosarcoma management.

RRM2 promotes liver metastasis of pancreatic cancer by stabilizing YBX1 and activating the TGF-beta pathway

Pancreatic cancer is one of the most malignant types of cancer, and despite recent advances in treatment, prognosis remains extremely poor. The most common site of pancreatic cancer metastasis is the liver. Elucidating the molecular mechanisms of pancreatic cancer progression and liver metastasis is essential for improving patients' survival. Ribonucleotide reductase subunit M2 (RRM2) has been linked to many types of cancers and is associated with tumor progression. However, the role of RRM2 in the liver metastasis of pancreatic cancer is still unclear. In this study, RRM2 was found to promote the malignant biological behavior of pancreatic cancer and enhance its liver metastasis. Further studies on the downstream molecular mechanisms of RRM2 revealed that RRM2 stabilizes YBX1, upregulates TGFBR1, and activates the TGF-beta pathway to promote pancreatic cancer progression and liver metastasis. In summary, these results suggest that RRM2 may be an effective therapeutic target for pancreatic cancer liver metastasis.

Regorafenib promotes antitumor progression in melanoma by reducing RRM2

Melanoma is a malignant tumor with a terrible prognosis. Although so many therapies are used for melanoma, the overall survival rate is still poor globally. Novel therapies are still required. In our study, the role and potential mechanism of regorafenib in melanoma are explored. Regorafenib has the ability to limit the growth, invasion, and metastasis of melanoma cells but to upregulate apoptosis-prompting markers (cleaved-PARP and Bax). RRM2 is identified to be the downstream target of regorafenib by RNA sequencing. In addition, we discovered that RRM2 inhibition and regorafenib have comparable effects on melanoma cells. Rescue experiments showed that RRM2 is crucial in regulating regorafenib's anti-melanoma progression. Moreover, ERK/E2F3 signaling influences regorafenib's ability to suppress melanoma cell growth. Ultimately, regorafenib significantly inhibits tumor growth in vivo. In conclusion, our finding demonstrated that regorafenib promotes antitumor progression in melanoma by reducing RRM2.

The value analysis of high-resolution thin-layer CT in the identification of early lung adenocarcinoma: An observation study

The aim of this study was to explore the clinical value of high-resolution thin-layer computed tomography (CT) for the identification of early lung adenocarcinoma. Ninety patients with early lung adenocarcinoma who were diagnosed and treated in our hospital were selected as study subjects and divided into noninvasive (NIG, n = 51) and invasive (IG, n = 39) groups according to their pathological findings. Both groups underwent high-resolution target scanning. Differences in lesion size, density, and distribution between the 2 groups were compared. Intergroup differences in the CT signs were examined. A receiver-operating characteristic curve was established to calculate the diagnostic efficacy of high-resolution, thin-layer CT for early lung adenocarcinoma infiltration. The maximum diameter and density of the tumors were significantly higher in the IG than in the NIG (P < .05). The proportions of CT signs of lobulation, spicule, and vessel convergence were higher in the IG patients compared to the NIG (P < .05). High-resolution thin-layer CT for the diagnosis of lung adenocarcinoma infiltration had an AUC of 0.6702 (P < .05), a diagnostic sensitivity of 64.10%, and a diagnostic specificity of 60.78%. High-resolution thin-layer CT had certain differential diagnostic efficacy for early lung adenocarcinoma, which clearly presents various CT signs of early lung adenocarcinoma lesions.

Membrane RRM2-positive cells represent a malignant population with cancer stem cell features in intrahepatic cholangiocarcinoma

BACKGROUND

Intrahepatic cholangiocarcinoma (iCCA) is one of the most lethal malignancies and highly heterogeneous. We thus aimed to identify and characterize iCCA cell subpopulations with severe malignant features.

METHODS

Transcriptomic datasets from three independent iCCA cohorts (iCCA cohorts 1-3, n = 382) and formalin-fixed and paraffin-embedded tissues from iCCA cohort 4 (n = 31) were used. An unbiased global screening strategy was established, including the transcriptome analysis with the activated malignancy/stemness (MS) signature in iCCA cohorts 1-3 and the mass spectrometry analysis of the sorted stemness reporter-positive iCCA cells. A group of cellular assays and subcutaneous tumor xenograft assay were performed to investigate functional roles of the candidate. Immunohistochemistry was performed in iCCA cohort 4 to examine the expression and localization of the candidate. Molecular and biochemical assays were used to evaluate the membrane localization and functional protein domains of the candidate. Cell sorting was performed and the corresponding cellular molecular assays were utilized to examine cancer stem cell features of the sorted cells.

RESULTS

The unbiased global screening identified RRM2 as the top candidate, with a significantly higher level in iCCA patients with the MS signature activation and in iCCA cells positive for the stemness reporter. Consistently, silencing RRM2 significantly suppressed iCCA malignancy phenotypes both in vitro and in vivo. Moreover, immunohistochemistry in tumor tissues of iCCA patients revealed an unreported cell membrane localization of RRM2, in contrast to its usual cytoplasmic localization. RRM2 cell membrane localization was then confirmed in iCCA cells via immunofluorescence with or without cell membrane permeabilization, cell fractionation assay and cell surface biotinylation assay. Meanwhile, an unclassical signal peptide and a transmembrane domain of RRM2 were revealed experimentally. They were essential for RRM2 trafficking to cell membrane via the conventional endoplasmic reticulum (ER)-Golgi secretory pathway. Furthermore, the membrane RRM2-positive iCCA cells were successfully sorted. These cells possessed significant cancer stem cell malignant features including cell differentiation ability, self-renewal ability, tumor initiation ability, and stemness/malignancy gene signatures. Patients with membrane RRM2-positive iCCA cells had poor prognosis.

CONCLUSIONS

RRM2 had an alternative cell membrane localization. The membrane RRM2-positive iCCA cells represented a malignant subpopulation with cancer stem cell features.

KIS, a target of SOX4, regulates the ID1-mediated enhancement of β-catenin to facilitate lung adenocarcinoma cell proliferation and metastasis

PURPOSE

Kinase interacting with stathmin (KIS) is a serine/threonine kinase involved in RNA processing and protein phosphorylation. Increasing evidence has suggested its involvement in cancer progression. The aim of this study was to investigate the role of KIS in the development of lung adenocarcinoma (LUAD). Dual luciferase assay was used to explore the relationship between KIS and SOX4, and its effect on ID1/β-catenin pathway.

METHODS

Real-time qPCR and western blot were used to assess the levels of KIS and other factors. Cell proliferation, migration, and invasion were monitored, and xenograft animal model were established to investigate the biological functions of KIS in vitro and in vivo.

RESULTS

In the present study, KIS was found to be highly expressed in LUAD tissues and cell lines. KIS accelerated the proliferative, migratory and invasive abilities of LUAD cells in vitro, and promoted the growth of LUAD in a mouse tumor xenograft model in vivo. Mechanistically, KIS activated the β-catenin signaling pathway by modulating the inhibitor of DNA binding 1 (ID1) and was transcriptionally regulated by SOX4 in LUAD cells.

CONCLUSION

KIS, a target of SOX4, regulates the ID1-mediated enhancement of β-catenin to facilitate LUAD cell invasion and metastasis.

Exosomes: a review of biologic function, diagnostic and targeted therapy applications, and clinical trials

Exosomes are extracellular vesicles generated by all cells and they carry nucleic acids, proteins, lipids, and metabolites. They mediate the exchange of substances between cells,thereby affecting biological properties and activities of recipient cells. In this review, we briefly discuss the composition of exocomes and exosome isolation. We also review the clinical applications of exosomes in cancer biology as well as strategies in exosome-mediated targeted drug delivery systems. Finally, the application of exosomes in the context of cancer therapeutics both in practice and literature are discussed.

Targeting of G protein-coupled receptor 39 alleviates angiotensin II-induced renal damage by reducing ribonucleotide reductase M2

Renal fibrosis, apoptosis and autophagy are the main pathological manifestations of angiotensin II (Ang II)-induced renal injury. G protein-coupled receptor 39 (GPR39) is highly expressed in various tissues including the kidney, but its role in the kidney is entirely unclear. This study was performed to investigate the underlying mechanism by which knockdown of GPR39 alleviated Ang II-induced renal injury. In vivo, GPR39 knockout (KO) mice were constructed and infused with Ang II for 4 weeks, followed by renal function tests. In vitro, Ang II-induced cells were treated with si-GPR39 for 48 h. Fibrosis, apoptosis and autophagy were detected in both cells and mice. The underlying mechanism was sought by mRNA transcriptome sequencing and validated in vitro. GPR39 was upregulated in renal tissues of mice with Ang II-mediated renal injury. Knockdown of GPR39 ameliorated renal fibrosis, apoptosis, and autophagy, and decreased the expression of ribonucleotide reductase M2 (RRM2). In vitro, knockdown of GPR39 was also identified to improve the Ang II-induced cell fibrosis, apoptosis, and autophagy. mRNA transcriptome results showed that knockout of GPR39 reduced the expression of RRM2 in Ang II-induced kidney tissue. Activation of RRM2 could reverse the therapeutic effect of GPR39 knockout, and the inhibitor of RRM2 could improve the cell fibrosis, apoptosis and autophagy caused by GPR39 agonist. These results indicated that targeting of GPR39 could alleviate Ang II-induced renal fibrosis, apoptosis, and autophagy via reduction of RRM2 expression, and GPR39 may serve as a potential target for Ang II-induced renal injury.

Mandibular metastasis of pulmonary adenocarcinoma: How unexpected could it be?

OBJECTIVE

Metastatic tumours of bone must be considered in all patients with unexplained bone pain and particularly in patients who present with a known cancer, localised pain at multiple sites, and radiographic findings suggestive of metastasis. The purpose of this report was to present a case of a pathological fracture of the mandible as a consequence of metastatic pulmonary adenocarcinoma.

MATERIALS AND METHODS

In July 2018 a 68-year-old male patient was hospitalised because of pulmonary adenocarcinoma and attended our department for an oral maxillo-facial evaluation. He complained of pain and swelling in the right temporomandibular region resulting in a reported functional limitation. An Orthopantomogram (OPG) demonstrated a right intracapsular condylar compound fracture associated with an osteolytic lesion at the condyle base with jagged margins. Subsequently, a CT scan with contrast of the maxillo-facial complex and a fine-needle aspiration of the lesion was performed.

RESULTS

CT images showed the presence of a right mandibular condyle fracture associated with a large osteolytic lesion which confirmed the pathological nature of the fracture. Fine-needle aspiration of the lesion confirmed its metastatic nature. It was not possible to proceed with a mandibular resection due to the critical clinical condition of the patient who died in September 2018.

CONCLUSION

Lung cancer frequently produces lytic-type metastasis, sometimes even in the jaw. In patients with an established diagnosis of lung cancer, any radiolucent lesion of the jaw or an unexplained painful symptomatology to the oro-maxillo facial complex should be placed in differential diagnosis with metastasis of the primary tumour.

IGF2BP3 regulates the expression of RRM2 and promotes the progression of rheumatoid arthritis via RRM2/Akt/MMP-9 pathway

BACKGROUND

Rheumatoid arthritis (RA) is a common inflammatory and autoimmune disease. Ribonucleotide Reductase Regulatory Subunit M2 (RRM2) is a crucial and a rate-limiting enzyme responsible for deoxynucleotide triphosphate(dNTP) production. We have found a high expression level of RRM2 in patients with RA, but the molecular mechanism of its action remains unclear.

METHODS

We analyzed the expression of hub genes in RA using GSE77298 datasets downloaded from Gene Expression Omnibus database. RRM2 and insulin-like growth factor-2 messenger ribonucleic acid (mRNA)-binding protein 3 (IGF2BP3) gene knockdown was achieved by infection with lentiviruses. The expression of RRM2, IGF2BP3, matrix metalloproteinase (MMP)-1, and MMP-9 were detected via western blotting assay. Cell viability was detected via 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) assay. MeRIP-qRT-PCR was performed to test the interaction of IGF2BP3 and RRM2 mRNA via m6A modification. Cell proliferation was determined by clone formation assay. Migration and invasion assays were performed using transwell Boyden chamber.

RESULTS

RRM2 and IGF2BP3 were highly expressed in clinical specimens and tumor necrosis factor alpha (TNF-α) and interleukin (IL)-1β-stimulated synovial cells. RRM2 and IGF2BP3 knockdown inhibited the proliferation, migration, and invasion of MH7A cells. The inhibitory effects of IGF2BP3 knockdown were effectively reversed by simultaneously overexpressing RRM2 in MH7A cells. By analyzing N6-methyladenosine (m6A)2Target database, five m6A regulatory target binding sites for IGF2BP3 were identified in RRM2 mRNA, suggesting a direct relationship between IGF2BP3 and RRM2 mRNA. Additionally, in RRM2 small hairpin (sh)RNA lentivirus-infected cells, the levels of phosphorylated Akt and MMP-9 were significantly decreased compared with control shRNA lentivirus-infected cells.

CONCLUSION

The present study demonstrated that RRM2 promoted the Akt phosphorylation leading to high expression of MMP-9 to promote the migration and invasive capacities of MH7A cells. Overall, IGF2BP promotes the expression of RRM2, and regulates the migration and invasion of MH7A cells via Akt/MMP-9 pathway to promote RA progression.

The application of Raman spectroscopy for the diagnosis and monitoring of lung tumors

Raman spectroscopy is an optical technique that uses inelastic light scattering in response to vibrating molecules to produce chemical fingerprints of tissues, cells, and biofluids. Raman spectroscopy strategies produce high levels of chemical specificity without requiring extensive sample preparation, allowing for the use of advanced optical tools such as microscopes, fiber optics, and lasers that operate in the visible and near-infrared spectral range, making them increasingly suitable for a wide range of medical diagnostic applications. Metal nanoparticles and nonlinear optical effects can improve Raman signals, and optimized fiber optic Raman probes can make real-time, in vivo, single-point observations. Furthermore, diagnostic speed and spatial accuracy can be improved through the multimodal integration of Raman measurements and other technologies. Recent studies have significantly contributed to the improvement of diagnostic speed and accuracy, making them suitable for clinical application. Lung cancer is a prevalent type of respiratory malignancy. However, the use of computed tomography for detection and screening frequently reveals numerous smaller lung nodules, which makes the diagnostic process more challenging from a clinical perspective. While the majority of small nodules detected are benign, there are currently no direct methods for identifying which nodules represent very early-stage lung cancer. Positron emission tomography and other auxiliary diagnostic methods for non-surgical biopsy samples from these small nodules yield low detection rates, which might result in significant expenses and the possibility of complications for patients. While certain subsets of patients can undergo curative treatment, other individuals have a less favorable prognosis and need alternative therapeutic interventions. With the emergence of new methods for treating cancer, such as immunotherapies, which can potentially extend patient survival and even lead to a complete cure in certain instances, it is crucial to determine the most suitable biomarkers and metrics for assessing the effectiveness of these novel compounds. This will ensure that significant treatment outcomes are accurately measured. This review provides a comprehensive overview of the prospects of Raman spectroscopy and its applications in the diagnosis and analysis of lung tumors.

A comprehensive analysis of ribonucleotide reductase subunit M2 for carcinogenesis in pan-cancer

BACKGROUND

Although there is evidence that ribonucleotide reductase subunit M2 (RRM2) is associated with numerous cancers, pan-cancer analysis has seldom been conducted. This study aimed to explore the potential carcinogenesis of RRM2 in pan-cancer using datasets from The Cancer Genome Atlas (TCGA).

METHODS

Data from the UCSC Xena database were analyzed to investigate the differential expression of RRM2 across multiple cancer types. Clinical data such as age, race, sex, tumor stage, and status were acquired to analyze the influence of RRM2 on the clinical characteristics of the patients. The role of RRM2 in the onset and progression of multiple cancers has been examined in terms of genetic changes at the molecular level, including tumor mutational burden (TMB), microsatellite instability (MSI), biological pathway changes, and the immune microenvironment.

RESULTS

RRM2 was highly expressed in most cancers, and there was an obvious correlation between RRM2 expression and patient prognosis. RRM2 expression is associated with the infiltration of diverse immune and endothelial cells, immune checkpoints, tumor mutational burden (TMB), and microsatellite instability (MSI). Moreover, the cell cycle is involved in the functional mechanisms of RRM2.

CONCLUSIONS

Our pan-cancer study provides a comprehensive understanding of the carcinogenesis of RRM2 in various tumors.

Schiff bases and their metal complexes to target and overcome (multidrug) resistance in cancer

Overcoming multidrug resistance (MDR) is one of the major challenges in cancer therapy. In this respect, Schiff base-related compounds (bearing a R1R2CNR3 bond) gained high interest during the past decades. Schiff bases are considered privileged ligands for various reasons, including the easiness of their preparation and the possibility to form complexes with almost all transition metal ions. Schiff bases and their metal complexes exhibit many types of biological activities and are used for the treatment and diagnosis of various diseases. Until now, 13 Schiff bases have been investigated in clinical trials for cancer treatment and hypoxia imaging. This review represents the first collection of Schiff bases and their complexes which demonstrated MDR-reversal activity. The areas of drug resistance covered in this article involve: 1) Modulation of ABC transporter function, 2) Targeting lysosomal ABCB1 overexpression, 3) Circumvention of ABC transporter-mediated drug efflux by alternative routes of drug uptake, 4) Selective activity against MDR cancer models (collateral sensitivity), 5) Targeting GSH-detoxifying systems, 6) Overcoming apoptosis resistance by inducing necrosis and paraptosis, 7) Reactivation of mutated p53, 8) Restoration of sensitivity to DNA-damaging anticancer therapy, and 9) Overcoming drug resistance through modulation of the immune system. Through this approach, we would like to draw attention to Schiff bases and their metal complexes representing highly interesting anticancer drug candidates with the ability to overcome MDR.

MELK aggravates lung adenocarcinoma by regulating EZH2 ubiquitination and H3K27me3 histone methylation of LATS2

We tried to elucidate the possible roles of maternal embryonic leucine pull chain kinase (MELK) in lung adenocarcinoma (LUAD) growth and metastasis. Differentially expressed genes in LUAD samples were analysed by the GEPIA database. Clinical tissue samples and cells were collected for MELK, EZH2 and LATS2 expression determination. Co-IP assay was used to verify the interaction between EZH2 and MELK; CHX tracking assay and ubiquitination assay detected the degradation of MELK on EZH2 ubiquitination. ChIP assay detected the enrichment of EZH2 and H3K27me3 on the LATS2 promoter region. LUAD cells were selected for in vitro validation, and the tumorigenic ability of LUAD cells was also observed in a transplantation tumour model of LUAD nude mice. MELK and EZH2 were highly expressed in LUAD samples, while LATS2 was lowly expressed. MELK interacted with EZH2 to inhibit its ubiquitination degradation; EZH2 elevated H3K27me3 modification in the LATS2 promoter to lower LATS2 expression. Silencing MELK or EZH2 or overexpressing LATS2 restrained LUAD cell proliferation and invasion, and facilitated their apoptosis. Silencing MELK or EZH2 or overexpressing LATS2 suppressed tumour formation in nude mice. This study demonstrated that MELK aggravated LUAD by upregulating EZH2 and downregulating LATS2.

Bioinformatics-based screening and analysis of the key genes involved in the influence of antiangiogenesis on myeloid-derived suppressor cells and their effects on the immune microenvironment

This study aimed to screen differentially expressed genes (DEGs) involved in the influence of antiangiogenic therapy on myeloid-derived suppressor cell (MDSC) infiltration and investigate their mechanisms of action. Data on DEGs after the action of antiangiogenic drugs in a pan-cancer context were obtained from the Gene Expression Omnibus (GEO) database. Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analyses were performed using the clusterProfiler package in R software. Single-sample gene set enrichment analysis was performed using the gene set variation analysis package to evaluate the levels of immune cells and the activity of immune-related pathways. The relationships of DEGs with the infiltration levels of MDSCs and specific immune cell subpopulations were investigated via gene module analysis. The top 10 key genes were subsequently obtained from PPI network analysis using the cytoHubba plugin of the Cytoscape platform. When the DEGs of the four datasets were intersected, a DEG in the intersection of three datasets and 12 DEGs in the intersection of two datasets were upregulated, and 28 DEGs in the intersection of two datasets were downregulated. GO and KEGG pathway enrichment analyses revealed that the DEGs were associated with multiple important signaling pathways closely related to tumor onset and development, including cell differentiation, cell proliferation, the cell cycle, and immune responses. Most downregulated genes in lung adenocarcinoma (LUAD) were positively correlated with MDSC expression. Only MGP was negatively correlated; the correlation between CACNG6 and MDSC expression was statistically insignificant. In lung squamous cell carcinoma (LUSC), the relationships of PMEPA1, PCDH7, NEURL1B, and CACNG6 with MDSC expression were statistically insignificant; MGP was negatively correlated with MDSC expression. The top 10 key genes with the highest degree scores obtained using the cytoHubba plugin of Cytoscape were AURKB, RRM2, BUB1, NUSAP1, PRC1, TOP2A, NCAPH, CENPA, KIF2C, and CCNA2. Most of these genes were upregulated in LUAD and associated with immune cell infiltration and prognosis in tumors. An analysis of the relationships between DEGs and infiltration by other specific immune cells revealed the presence of consistent patterns in the downregulated genes, which exhibited positive correlations with the levels of Th2 cells, γδ T cells, and CD56dim NK cells, and negative correlations with other infiltrating immune cells. Antiangiogenic therapy may regulate MDSC infiltration through multiple important signaling pathways closely associated with tumor onset and development, such as cell differentiation, cell proliferation, the cell cycle, and immune responses. Antiangiogenic drugs may exert effects by affecting various types of infiltrating cells associated with immune suppression.

Evaluation of the clinical significance of long non-coding RNA MALAT1 genetic variants in human lung adenocarcinoma

Lung adenocarcinoma (LUAD) is the most frequent histological subtype of lung cancer, which is the most common malignant tumor and the main cause of cancer-related mortality globally. Recent reports revealed that long non-coding RNA (lncRNA) of metastasis-associated lung adenocarcinoma transcript 1 (MALAT1) plays a crucial role in tumorigenesis and metastasis development in lung cancer. However, the contribution of MALAT1 genetic variants to the development of LUAD is unclear, especially in epidermal growth factor receptor (EGFR) mutation status. In this study, 272 LADC patients with different EGFR status were recruited to dissect the allelic discrimination of the MALAT1 polymorphisms at rs3200401, rs619586, and rs1194338. The findings of the study showed that MALAT1 polymorphisms rs3200401, rs619586, and rs1194338 were not associated to LUAD susceptibility; however, rs3200401 polymorphisms was significantly correlated to EGFR wild-type status and tumor stages in LUAD patients in dominant model (p=0.016). Further analyses using the datasets from The Cancer Genome Atlas (TCGA) revealed that lower MALAT1 mRNA levels were associated with the advanced stage, and lymph node metastasis in LADC patients. In conclusion, our results showed that MALAT1 rs3200401 polymorphisms dramatically raised the probability of LUAD development.

Nuclear protein NOP2 serves as a poor-prognosis predictor of LUAD and aggravates the malignancy of lung adenocarcinoma cells

Recent studies have shown that NOP2, a nucleolar protein, is up-regulated in various cancers, suggesting a potential link to tumor aggressiveness and unfavorable outcomes. This study examines NOP2's role in lung adenocarcinoma (LUAD), a context where its implications remain unclear. Utilizing bioinformatics, we assessed 513 LUAD and 59 normal tissue samples from The Cancer Genome Atlas (TCGA) to explore NOP2's diagnostic and prognostic significance in LUAD. Additionally, in vitro experiments compared NOP2 expression between Beas-2b and A549 cells. Advanced databases and analytical tools, including LINKEDOMICS, STRING, and TISIDB, were employed to further elucidate NOP2's association with LUAD. Our findings indicate a significantly higher expression of NOP2 mRNA and protein in A549 cells compared to Beas-2b cells (P < 0.001). In LUAD, elevated NOP2 levels were linked to decreased Overall Survival (OS) and advanced clinical stages. Univariate Cox analysis revealed that high NOP2 expression correlated with poorer OS in LUAD (P < 0.01), a finding independently supported by multivariate Cox analysis (P < 0.05). The relationship between NOP2 expression and LUAD risk was presented via a Nomogram. Additionally, Gene Set Enrichment Analysis (GSEA) identified seven NOP2-related signaling pathways. A focal point of our research was the interplay between NOP2 and tumor-immune interactions. Notably, a negative correlation was observed between NOP2 expression and the immune infiltration levels of macrophages, neutrophils, mast cells, Natural Killer (NK) cells, and CD8 + T cells in LUAD. Moreover, the expression of NOP2 was related to the sensitivity of various chemotherapeutic drugs. In vitro, we found that downregulating NOP2 can decrease the proliferation, migration and invasion of A549 cells. Furthermore, NOP2 can regulate Caspase3-mediated apoptosis. Collectively, particularly regarding prognosis, immune infiltration and vitro experiments, these findings suggest NOP2's potential of serving as a poor-prognostic biomarker for LUAD and aggravating the malignancy of lung adenocarcinoma cells.

STS ⅡA inhibited angiogenesis of lung adenocarcinoma by activating FOXO3 to inhibit CXCL1/STAT3/VEGF pathway

BACKGROUND

Lung adenocarcinoma (LUAD) is the most popular type of lung cancer. Sulfotanshinone IIA sodium (STS IIA) has been proven to have an anticancer effect. However, its role in LUAD and its underlying mechanism remain unclear.

OBJECTIVE

To investigate the role and mechanism of STS IIA in LUAD angiogenesis.

METHODS

The mRNA levels of genes, including forkhead box O3 (FOXO3) and chemokine C-X-C motif ligand 1 (CXCL1), were detected by qRT-PCR. The levels of proteins, including FOXO3, CXCL1, and vascular endothelial growth factor (VEGF), were measured by Western blot. The proliferation and angiogenesis of human umbilical vein endothelial cells (HUVECs) were detected by the EdU assay and the tubule formation assay, respectively. The binding relationship between FOXO3 and CXCL1 was detected by dual-luciferase reporter assay.

RESULTS

Our results illustrated that different concentrations of STS IIA inhibited the proliferation and angiogenesis of HUVECs. FOXO3 regulated the proliferation and angiogenesis of HUVECs inhibited by STS ⅡA via targeting CXCL1. Subsequently, we proved that exogenous CXCL1 alleviated the inhibition of proliferation and angiogenesis of HUVECs regulated by STS IIA via activating the STAT3/VEGF pathway. Finally, we found that STS IIA inhibited the angiogenesis of lung adenocarcinoma though FOXO3 to inhibit the CXCL1/STAT3/VEGF pathway.

CONCLUSION

Our study finally elucidated the underlying molecular mechanism by which STS ⅡA inhibits LUAD angiogenesis.

Expression and clinical role of PRDX6 in lung adenocarcinoma

OBJECTIVE

To explore the levels of expression and clinical role of peroxiredoxin 6 (PRDX6) in lung adenocarcinoma.

METHODS

This retrospective study used a series of bioinformatics methods to detect the levels of expression of and mutations in the PRDX6 gene in a range of cancers and lung adenocarcinoma. Immunohistochemistry was used to verify the levels of expression of PRDX6 protein in samples of lung adenocarcinoma compared with normal adjacent tissue. The effect of PRDX6 gene knockdown on the in vitro proliferation of a lung adenocarcinoma cell line was measured. Bioinformatics methods were used to determine the diagnostic value and impact on survival of the PRDX6 gene in patients with lung adenocarcinoma.

RESULTS

The results showed that the PRDX6 gene was highly expressed in lung adenocarcinoma and there were five mutations at different sites on the gene. PRDX6 promoted the proliferation of the lung adenocarcinoma cell line. The survival duration of lung adenocarcinoma patients with high levels of PRDX6 gene expression was significantly shorter than that of patients with low PRDX6 gene expression.

CONCLUSION

PRDX6 is highly expressed in lung adenocarcinoma and higher levels of expression of the PRDX6 gene were associated with a poorer prognosis.

Machine learning reveals diverse cell death patterns in lung adenocarcinoma prognosis and therapy

Cancer cell growth, metastasis, and drug resistance pose significant challenges in the management of lung adenocarcinoma (LUAD). However, there is a deficiency in optimal predictive models capable of accurately forecasting patient prognoses and guiding the selection of targeted treatments. Programmed cell death (PCD) pathways play a pivotal role in the development and progression of various cancers, offering potential as prognostic indicators and drug sensitivity markers for LUAD patients. The development and validation of predictive models were conducted by integrating 13 PCD patterns with comprehensive analysis of bulk RNA, single-cell RNA transcriptomics, and pertinent clinicopathological details derived from TCGA-LUAD and six GEO datasets. Utilizing the machine learning algorithms, we identified ten critical differentially expressed genes associated with PCD in LUAD, namely CHEK2, KRT18, RRM2, GAPDH, MMP1, CHRNA5, TMPRSS4, ITGB4, CD79A, and CTLA4. Subsequently, we conducted a programmed cell death index (PCDI) based on these genes across the aforementioned cohorts and integrated this index with relevant clinical features to develop several prognostic nomograms. Furthermore, we observed a significant correlation between the PCDI and immune features in LUAD, including immune cell infiltration and the expression of immune checkpoint molecules. Additionally, we found that patients with a high PCDI score may exhibit resistance to immunotherapy and standard adjuvant chemotherapy regimens; however, they may benefit from other FDA-supported drugs such as docetaxel and dasatinib. In conclusion, the PCDI holds potential as a prognostic signature and can facilitate personalized treatment for LUAD patients.

Targeting of RRM2 suppresses DNA damage response and activates apoptosis in atypical teratoid rhabdoid tumor

BACKGROUND

Atypical teratoid rhabdoid tumors (ATRT) is a rare but aggressive malignancy in the central nervous system, predominantly occurring in early childhood. Despite aggressive treatment, the prognosis of ATRT patients remains poor. RRM2, a subunit of ribonucleotide reductase, has been reported as a biomarker for aggressiveness and poor prognostic conditions in several cancers. However, little is known about the role of RRM2 in ATRT. Uncovering the role of RRM2 in ATRT will further promote the development of feasible strategies and effective drugs to treat ATRT.

METHODS

Expression of RRM2 was evaluated by molecular profiling analysis and was confirmed by IHC in both ATRT patients and PDX tissues. Follow-up in vitro studies used shRNA knockdown RRM2 in three different ATRT cells to elucidate the oncogenic role of RRM2. The efficacy of COH29, an RRM2 inhibitor, was assessed in vitro and in vivo. Western blot and RNA-sequencing were used to determine the mechanisms of RRM2 transcriptional activation in ATRT.

RESULTS

RRM2 was found to be significantly overexpressed in multiple independent ATRT clinical cohorts through comprehensive bioinformatics and clinical data analysis in this study. The expression level of RRM2 was strongly correlated with poor survival rates in patients. In addition, we employed shRNAs to silence RRM2, which led to significantly decrease in ATRT colony formation, cell proliferation, and migration. In vitro experiments showed that treatment with COH29 resulted in similar but more pronounced inhibitory effect. Therefore, ATRT orthotopic mouse model was utilized to validate this finding, and COH29 treatment showed significant tumor growth suppression and prolong overall survival. Moreover, we provide evidence that COH29 treatment led to genomic instability, suppressed homologous recombinant DNA damage repair, and subsequently induced ATRT cell death through apoptosis in ATRT cells.

CONCLUSIONS

Collectively, our study uncovers the oncogenic functions of RRM2 in ATRT cell lines, and highlights the therapeutic potential of targeting RRM2 in ATRT. The promising effect of COH29 on ATRT suggests its potential suitability for clinical trials as a novel therapeutic approach for ATRT.

Identifying genes associated with resistance to KRAS G12C inhibitors via machine learning methods

BACKGROUND

Targeted therapy has revolutionized cancer treatment, greatly improving patient outcomes and quality of life. Lung cancer, specifically non-small cell lung cancer, is frequently driven by the G12C mutation at the KRAS locus. The development of KRAS inhibitors has been a breakthrough in the field of cancer research, given the crucial role of KRAS mutations in driving tumor growth and progression. However, over half of patients with cancer bypass inhibition show limited response to treatment. The mechanisms underlying tumor cell resistance to this treatment remain poorly understood.

METHODS

To address above gap in knowledge, we conducted a study aimed to elucidate the differences between tumor cells that respond positively to KRAS (G12C) inhibitor therapy and those that do not. Specifically, we analyzed single-cell gene expression profiles from KRAS G12C-mutant tumor cell models (H358, H2122, and SW1573) treated with KRAS G12C (ARS-1620) inhibitor, which contained 4297 cells that continued to proliferate under treatment and 3315 cells that became quiescent. Each cell was represented by the expression levels on 8687 genes. We then designed an innovative machine learning based framework, incorporating seven feature ranking algorithms and four classification algorithms to identify essential genes and establish quantitative rules.

RESULTS

Our analysis identified some top-ranked genes, including H2AFZ, CKS1B, TUBA1B, RRM2, and BIRC5, that are known to be associated with the progression of multiple cancers.

CONCLUSION

Above genes were relevant to tumor cell resistance to targeted therapy. This study provides important insights into the molecular mechanisms underlying tumor cell resistance to KRAS inhibitor treatment.

[Mechanism of miR-186-5p Regulating PRKAA2 to Promote Ferroptosis in Lung Adenocarcinoma Cells]

BACKGROUND

Lung adenocarcinoma (LUAD) is the most common type of non-small cell lung cancer, and any change of miRNAs expression will affect the degree of target regulation, thus affecting intracellular homeostasis. This study verified that miR-186-5p could inhibit the proliferation, migration and invasion of LUAD cells by regulating PRKAA2.

METHODS

Previous investigations found that the expression of miR-186-5p was markedly suppressed in LUAD. Bioinformatics method is used to predict the target protein related to ferroptosis downstream and inquire about its expression level in LUAD and its influence on the survival of patients. Double luciferase verified the binding site of PRKAA2 and miR-186-5p. Quantitative real-time polymerase chain reaction (qRT-PCR) and Western blot were used to detect the expression of PRKAA2. The effects of miR-186-5p of LUAD cells as well as the mechanism by which miR-186-5p inhibits Fer-1's sensitivity to ferroptosis were confirmed by EdU, Transwell, and scratch assays. The effect of miR-186-5p on the amount of reactive oxygen species (ROS) in LUAD cells was discovered using ROS experiment. Malondialdehyde (MDA) and glutathione (GSH) experiments were used to detect the effects of miR-186-5p and PRKAA2 on ferroptosis index of LUAD cells. The concentration of lipid ROS (L-ROS) in LUAD cells were measured using the L-ROS tests to determine the effects of miR-186-5p and PRKAA2.

RESULTS

The expression of PRKAA2 is up-regulated, and a high level of PRKAA2 expression was associated with a poor prognosis for patients with LUAD. Overexpression of miR-186-5p decreased the gene and protein expression of PRKAA2. By promoting ferroptosis, miR-186-5p overexpression prevented lung cancer cells from proliferating, invading, and migrating. ROS could be produced in higher amounts in LUAD cells due to miR-186-5p. Overexpression of miR-186-5p and knockdown PRKAA2 up-regulated MDA content and reduced GSH content in LUAD cells, respectively. miR-186-5p could increase the content of L-ROS and promote the ferroptosis sensitivity of LUAD cells by targeting PRKAA2.

CONCLUSIONS

miR-186-5p promotes ferroptosis of LUAD cells through targeted regulation of PRKAA2, thus inhibiting the proliferation, invasion and migration of LUAD.
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Remodeling of Chromatin Accessibility Regulates the Radiological Responses of NSCLC A549 Cells to High-LET Carbon Ions

Carbon-ion radiation therapy (CIRT) may offer remarkable advantages in cancer treatment with its unique physical and biological characteristics. However, the underlying epigenetic regulatory mechanisms of cancer response to CIRT remain to be identified. In this study, we showed consistent but different degrees of biological effects induced in NSCLC A549 cells by carbon ions of different LET. The genome-wide chromatin accessibility and transcriptional profiles of carbon ion-treated A549 cells were performed using transposase-accessible chromatin sequencing (ATAC-seq) and RNA-seq, respectively, and further gene regulatory network analysis was performed by integrating the two sets of genomic data. Alterations in chromatin accessibility by carbon ions of different LET predominantly occurred in intron, distal intergenic and promoter regions of differential chromatin accessibility regions. The transcriptional changes were mainly regulated by proximal chromatin accessibility. Notably, CCCTC-binding factor (CTCF) was identified as a key transcription factor in the cellular response to carbon ions. The target genes regulated by CTCF in response to carbon ions were found to be closely associated with the LET of carbon ions, particularly in the regulation of gene transcription within the DNA replication- and metabolism-related signaling pathways. This study provides a regulatory profile of genes involved in key signaling pathways and highlighted key regulatory elements in NSCLC A549 cells during CIRT, which expands our understanding of the epigenetic mechanisms of carbon ion-induced biological effects and reveals an important role for LET in the regulation of changes in chromatin accessibility, although further research is needed.

Analysis of two-gene signatures and related drugs in small-cell lung cancer by bioinformatics

Small-cell lung cancer (SCLC) has a poor prognosis and can be diagnosed with systemic metastases. Nevertheless, the molecular mechanisms underlying the development of SCLC are unclear, requiring further investigation. The current research aims to identify relevant biomarkers and available drugs to treat SCLC. The bioinformatics analysis comprised three Gene Expression Omnibus datasets (including GSE2149507, GSE6044, and GSE30219). Using the limma R package, we discovered differentially expressed genes (DEGs) in the current work. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes analyses were made by adopting the DAVID website. The DEG protein-protein interaction network was built based on the Search Tool for the Retrieval of Interacting Genes/Proteins website and visualized using the CytoHubba plugin in Cytoscape, aiming to screen the top ten hub genes. Quantitative real-time polymerase chain reaction was adopted for verifying the level of the top ten hub genes. Finally, the potential drugs were screened and identified using the QuartataWeb database. Totally 195 upregulated and 167 downregulated DEGs were determined. The ten hub genes were NCAPG, BUB1B, TOP2A, CCNA2, NUSAP1, UBE2C, AURKB, RRM2, CDK1, and KIF11. Ten FDA-approved drugs were screened. Finally, two genes and related drugs screened could be the prospective drug targets for SCLC treatment.

Ribonucleotide reductase regulatory subunit M2 (RRM2) as a potential sero-diagnostic biomarker in non-small cell lung cancer

OBJECTIVES

Non-small cell lung cancer (NSCLC) is a major cause of cancer-related death worldwide. Most cases are diagnosed at an advanced stage using current tumor markers. Here, we aimed to identify potential novel potential biomarkers for NSCLC.

MATERIAL/METHODS

Four independent datasets from the Gene Expression Omnibus database were analyzed. The relative expression of ribonucleotide reductase regulatory subunit M2 (RRM2) mRNA in 30 paired of NSCLC paired tissues was measured by reverse transcription quantitative PCR. Serum levels of cytokeratin fragment 21-1 (CYFRA21-1), pro-gastrin-releasing peptide (ProGRP), carcinoembryonic antigen (CEA), and neuron-specific enolase (NSE) were measured using electrochemiluminescence immunoassays, and serum RRM2 levels were evaluated by an enzyme-linked immunosorbent assay.

RESULTS

The mRNA expression level of RRM2 was significantly increased in most NSCLC lesions compared to para-adjacent tissues. Serum RRM2 levels in NSCLC patients were significantly elevated compared to healthy controls and were also associated with distant metastasis and histological type, but not with tumor size or lymph node metastasis. Receiver operating characteristic curve analysis showed a higher diagnostic ratio for NSCLC using RRM2 alone compared to other traditional tumor markers.

CONCLUSIONS

RRM2 is a potential sero-diagnostic biomarker for NSCLC.

Identification and verification of novel immune-related ferroptosis signature with excellent prognostic predictive and clinical guidance value in hepatocellular carcinoma

Background: Immunity and ferroptosis often play a synergistic role in the progression and treatment of hepatocellular carcinoma (HCC). However, few studies have focused on identifying immune-related ferroptosis gene biomarkers. Methods: We performed weighted gene co-expression network analysis (WGCNA) and random forest to identify prognostic differentially expressed immune-related genes (PR-DE-IRGs) highly related to HCC and characteristic prognostic differentially expressed ferroptosis-related genes (PR-DE-FRGs) respectively to run co-expression analysis for prognostic differentially expressed immune-related ferroptosis characteristic genes (PR-DE-IRFeCGs). Lasso regression finally identified 3 PR-DE-IRFeCGs for us to construct a prognostic predictive model. Differential expression and prognostic analysis based on shared data from multiple sources and experimental means were performed to further verify the 3 modeled genes' biological value in HCC. We ran various performance testing methods to test the model's performance and compare it with other similar signatures. Finally, we integrated composite factors to construct a comprehensive quantitative nomogram for accurate prognostic prediction and evaluated its performance. Results: 17 PR-DE-IRFeCGs were identified based on co-expression analysis between the screened 17 PR-DE-FRGs and 34 PR-DE-IRGs. Multi-source sequencing data, QRT-PCR, immunohistochemical staining and testing methods fully confirmed the upregulation and significant prognostic influence of the three PR-DE-IRFeCGs in HCC. The model performed well in the performance tests of multiple methods based on the 5 cohorts. Furthermore, our model outperformed other related models in various performance tests. The immunotherapy and chemotherapy guiding value of our signature and the comprehensive nomogram's excellent performance have also stood the test. Conclusion: We identified a novel PR-DE-IRFeCGs signature with excellent prognostic prediction and clinical guidance value in HCC.

Improvement of variables interpretability in kernel PCA

BACKGROUND

Kernel methods have been proven to be a powerful tool for the integration and analysis of high-throughput technologies generated data. Kernels offer a nonlinear version of any linear algorithm solely based on dot products. The kernelized version of principal component analysis is a valid nonlinear alternative to tackle the nonlinearity of biological sample spaces. This paper proposes a novel methodology to obtain a data-driven feature importance based on the kernel PCA representation of the data.

RESULTS

The proposed method, kernel PCA Interpretable Gradient (KPCA-IG), provides a data-driven feature importance that is computationally fast and based solely on linear algebra calculations. It has been compared with existing methods on three benchmark datasets. The accuracy obtained using KPCA-IG selected features is equal to or greater than the other methods' average. Also, the computational complexity required demonstrates the high efficiency of the method. An exhaustive literature search has been conducted on the selected genes from a publicly available Hepatocellular carcinoma dataset to validate the retained features from a biological point of view. The results once again remark on the appropriateness of the computed ranking.

CONCLUSIONS

The black-box nature of kernel PCA needs new methods to interpret the original features. Our proposed methodology KPCA-IG proved to be a valid alternative to select influential variables in high-dimensional high-throughput datasets, potentially unravelling new biological and medical biomarkers.

Multiple Omics Analysis of the Role of RBM10 Gene Instability in Immune Regulation and Drug Sensitivity in Patients with Lung Adenocarcinoma (LUAD)

OBJECTIVE

The RNA-binding protein RBM10 can regulate apoptosis during the proliferation and migration of pancreatic cancer, endometrial cancer, and osteosarcoma cells; however, the molecular mechanism underlying lung adenocarcinoma is rarely reported. Recent studies have detected multiple truncated and missense mutations in RBM10 in lung adenocarcinoma, but the role of RBM10 in lung adenocarcinoma is unclear. This study mainly explored the immune regulation mechanism of RBM10 in the development of lung adenocarcinoma and its influence on sensitivity to targeted therapy drugs.

METHODS

The transcriptome data of CGAP were used to analyze the RNA-seq data of lung adenocarcinoma patients from different subgroups by using the CIBERSORT algorithm to infer the relative proportion of various immune infiltrating cells, and Spearman correlation analysis was performed to determine the gene expression and immune cell content. In addition, this study utilized drug trial data from the GDSC database. The IC50 estimates for each specific targeted therapy were obtained by using a regression method, and the regression and prediction accuracy were tested via ten cross-validations with the GDSC training set. An immunohistochemical test was performed on the samples of 20 patients with lung adenocarcinoma in the subcomponent analysis of immune cells, and the protein expression of RBM10 in lung adenocarcinoma tissues was verified by cellular immunofluorescence assays. Nucleic acids were extracted at low temperatures, and qRT-PCR was used to verify the expression levels of the mRNA of RBM10 in lung adenocarcinoma tissues and normal tissues (p < 0.05).

RESULTS

After screening and inclusion using a machine language, the results showed that RBM10 was significantly highly expressed in the lung adenocarcinoma tissues. The related signaling pathways were mainly concentrated in ncRNA processing, rRNA metabolic processes, ribosome biogenesis, and the regulation of translation. The qRT-PCR for 20 lung adenocarcinoma tissues showed that the expression of RBM10 in these tissues was significantly different from that in normal tissues (p = 0.0255). Immunohistochemistry analysis and cell immunofluorescence staining also confirmed that RBM10 was involved in the immune regulation of lung adenocarcinoma tissues, and the number of immune cell aggregations was significantly higher than that of the control group. RBM10 regulates B cell memory-CIBERSORT (p = 0.042) and B cell memory-CIBERSOTRT-abs (p = 0.027), cancer-associated fibroblast-EPIC (p = 0.001), cancer-associated fibroblast- MCPCounter (p = 0.0037), etc. The risk score was significantly associated with the sensitivity of patients to lapatinib (p = 0.049), nilotinib (p = 0.015), pazopanib (p = 0.001), and sorafenib (p = 0.048).

CONCLUSIONS

RBM10 can inhibit the proliferation and invasion of lung adenocarcinoma cells through negative regulation and promote the apoptosis of lung adenocarcinoma cells through immunomodulatory mechanisms. The expression level of RBM10 affects the efficacy of targeted drug therapy and the survival prognosis of lung adenocarcinoma patients, which has a certain guiding significance for the clinical treatment of these patients.

Emerging roles of ferroptosis-related miRNAs in tumor metastasis

Ferroptosis, a novel mode of cell death dependent on iron and reactive oxygen species, has been extensively explored during malignant tumors metastasis. Ferroptosis can interact with multiple components of the tumor microenvironment to regulate metastasis. These interactions generally include the following aspects: (1) Epithelial-mesenchymal transformation, which can help cancer cells increase their sensitivity to ferroptosis while they have multiple mechanisms to fight against it; (2) Disorder of iron metabolism in cancer stem cells which maintains their stem characteristics; (3) Polarization of M0 macrophages to M2. (4) The paradoxical effects of iron metabolism and CD8 + T cells induced by ferroptosis (5) Regulation of angiogenesis. In addition, ferroptosis can be regulated by miRNAs through the reprogramming of various intracellular metabolism processes, including the regulation of the glutathione- glutathione peroxidase 4 pathway, glutamic acid/cystine transport, iron metabolism, lipid metabolism, and oxidative stress. Therefore, there are many potential interactions between ferroptosis-related miRNAs and tumor metastasis, including interaction with cancer cells and immune cells, regulating cytokines, and angiogenesis. This review focuses on the role of ferroptosis-related miRNA in tumor metastasis, aiming to help readers understand their relationship and provide a new perspective on the potential treatment strategies of malignant tumors.

MiR-17- 5p/RRM2 regulated gemcitabine resistance in lung cancer A549 cells

The main objective of this study is to investigate the regulatory roles of the miR-17-5p/RRM2 axis in A549/G+ cells' gemcitabine resistance. The cell viability was determined using CCK8 and clonogenic assays. Gene expression level analysis by RT-qPCR and Western blotting. Cell cycle analysis by flow cytometry. The dual luciferase activity assay was used to verify the target gene of miR-17-5p. In gemcitabine-resistant cell line A549G+, the drug resistance decreased after up-regulation of MiR-17-5p expression. The proportion of cell cycle G1 phase increased, and the S phase decreased. The expression level of cell cycle-related proteins CCNE1, CCNA2, and P21 decreased. The opposite results emerged after the down-regulation of MiR-17-5p expression in gemcitabine-sensitive cell line A549G-. The expression levels of PTEN and PIK3 in A549G+ cells were higher than in A549G-cells, but p-PTEN was lower than that in A549G-. After up-regulating the expression of MiR-17-5p in A549G+, the expression levels of p-PTEN increased, and the expression level of p-AKT decreased. After down-regulating miR-17-5p expression, the opposite results emerged. The dual-luciferase reporter assay and restorative experiments proved that RRM2 is one of the target genes for MiR-17-5p. Our results suggested that the miR-17-5p/RRM2 axis could adjust gemcitabine resistance in A549 cells, and the p-PTEN/PI3K/AKT signal pathway might be involved in this regulatory mechanism.

RNF182 induces p65 ubiquitination to affect PDL1 transcription and suppress immune evasion in lung adenocarcinoma

BACKGROUND

The RING finger (RNF) proteins are a large group of ubiquitin ligases whose aberrant expression is often associated with disease progression. This study examines the function of RNF protein 182 (RNF182) in lung adenocarcinoma (LUAD) cells and its impact on p65 and programmed death ligand 1 (PDL1) regulation.

METHODS

Expression of RNF182, p65, and PDL1 in LUAD tissues and cells was measured using immunohistochemistry, reverse transcription quantitative polymerase chain reaction (RT-qPCR), and/or western blot (WB) assays. LUAD cells were induced to overexpress RNF182 and p65, followed by cell counting kit-8, colony formation, Transwell, and flow cytometry assays to evaluate the cells' malignant phenotype. Coimmunoprecipitation and WB assays were used to verify RNF182's effect on p65 ubiquitination. Chromatin immunoprecipitation-qPCR and luciferase assays were used to analyze p65's transcriptional regulation of PDL1. Coculture of LUAD with CD8+ cytotoxic T cells was performed to detect lactate dehydrogenase release and interferon-γ and interleukin-2 concentrations. LUAD cells were implanted in mice to analyze tumorigenicity.

RESULTS

RNF182 was poorly expressed, while p65 and PDL1 were highly expressed in LUAD tissues and cells. RNF182 overexpression suppressed the malignant properties of LUAD cells, and it promoted p65 ubiquitination and protein degradation. p65 activated PDL1 transcription. Overexpression of RNF182 suppressed the PDL1 expression, increased the cytotoxicity in LUAD cells cocultured with CD8+ T cells, and suppressed the tumorigenesis of cancer cells in vivo. However, these tumor-suppressive effects of RNF182 on LUAD cells were blocked by p65 restoration.

CONCLUSION

This research demonstrates that RNF182 induces p65 ubiquitination to suppress PDL1 transcription and immunosuppression in LUAD.

Over-expression of RRM2 predicts adverse prognosis correlated with immune infiltrates: A potential biomarker for hepatocellular carcinoma

Background

Ribonucleotide reductase regulatory subunit M2 (RRM2) has been reported to be an oncogene in some malignant tumors, such as lung adenocarcinoma, oral squamous cell carcinoma, glioblastoma, and breast cancer. However, the clinical significance of RRM2 in hepatocellular carcinoma has been less studied. The aim of this study was to assess the importance of RRM2 in hepatocellular carcinoma (HCC) based on the Cancer Genome Atlas (TCGA) database.

Methods

The RRM2 expression levels and clinical features were downloaded from the TCGA database. Immunohistochemistry results between tumor tissues and normal tissues were downloaded from the Proteinatlas database. Meanwhile, the expression levels of RRM2 in tumor and paraneoplastic tissues were further verified by qRT-PCR and Western Blotting. Gene Ontology (GO)/Kyoto Encyclopedia of Genes and Genomes (KEGG) and protein-protein-interactions (PPI) network were constructed to analyze RRM2-related downstream molecules. In addition, RRM2 expression-related pathways performed by gene set enrichment analysis (GSEA). Association analysis of RRM2 gene expression and immune infiltration was performed by single-sample GSEA (ssGSEA).

Results

The RRM2 expression level in tumor tissues was higher than normal tissues (P &lt;0.001). The elevated expression of RRM2 in HCC was significantly correlated with T stage (P &lt;0.05), pathologic stage (P &lt;0.05), tumor status (P &lt;0.05), histologic grade (P&lt;0.001), and AFP (P &lt;0.001). HCC with higher RRM2 expression was positively associated with worse OS (overall survival), PFS (progression-free survival), and DSS (disease-specific survival). In the univariate analysis, the expression of RRM2, T stage, M stage, pathologic stage, and tumor status were negatively correlated with OS (P &lt;0.05). Further analysis using multivariate Cox regression showed that tumor status (P&lt;0.01) and RRM2 expression (P&lt;0.05) were independent prognostic factors of OS in HCC. GO/KEGG analysis showed that the critical biological process (chromosome condensation and p53 signaling pathway) might be the possible function mechanism in promoting HCC. Moreover, GSEA showed that several pathways were enriched in RRM2 high-expression samples, including PD-1 signaling, cell cycle, P27 pathway, and T cell receptor signaling pathway. RRM2 was significantly correlated with the infiltration level of CD8 T cells, Cytotoxic cells, DCs, Neutrophils, NK cells, and T helper cells (P &lt;0.05).

Conclusion

Over-expression of RRM2 predict adverse prognosis and is correlated with immune infiltrates in HCC. RRM2 may be a significant molecular biomarker for HCC diagnosis and prognosis.

SKA1 is overexpressed in laryngocarcinoma and modulates cell growth via P53 signaling pathway

Laryngocarcinoma is one of the most frequent malignancies occurring in the head and neck. The roles of spindle- and kinetochore-associated complex 1 (SKA1) in the malignant progression of several cancers have already been discussed. However, the precise significance and action's mechanism of SKA1 in laryngocarcinoma remain largely unknown. In this study, SKA1 was shown to be strongly expressed in laryngocarcinoma tissues and cells, and higher expression of SKA1 was associated with more severe tumor infiltration, larger tumor diameter, higher risk of lymphatic metastasis and later pathological stage. Additionally, loss-of-function assays in vitro suggested that SKA1 depletion caused a reduction in cell proliferation, migration, and colony formation as well as an increase in apoptosis. In animal experiments, tumors generated from AMC-HN-8 cells with SKA1 depletion exhibited declined tumor volume and weight. Similarly, the detection of Ki67 protein in xenograft tumor tissues reflected that knocking down SKA1 curbed tumor growth in vivo. Further exploration on downstream mechanism revealed that after treatment with Pifithrin-α, the suppression in proliferation level caused by SKA1 knockdown was reversed, while the increase of cell apoptosis was withdrawn; at the molecular level, Pifithrin-α treatment caused p-P53 and Bax diminished, while Bcl-2 ameliorated. In short, SKA1 promotes the development of laryngocarcinoma via activating the P53 signaling pathway.

Comprehensively Analyze the Prognosis Significance and Immune Implication of PTPRO in Lung Adenocarcinoma

Immunotherapy for lung adenocarcinoma (LUAD) is considered to be a promising treatment option, but only a minority of patients benefit from it. Therefore, it is essential to clarify the regulation mechanism of the tumor immune microenvironment (TIM) of the LUAD. Receptor-type protein tyrosine phosphatase (PTPRO) has been shown to be a tumor suppressor in a variety of tumor; however, its role in LUAD has never been reported. In this study, we first found that PTPRO was lowly expressed in LUAD and positively correlated with patient prognosis. Next, we investigated the relationship between PTPRO and clinical characteristics, and the results showed that gender, age, T, and stage were closely related to the expression level of PTPRO. Moreover, we performed univariate and multivariate analyses, and the results revealed that PTPRO was a protective factor for LUAD. By constructing a nomogram based on the expression level of PTPRO and various clinical characteristics, it was proved that the nomogram has a good predictive capacity. Furthermore, we analyzed the coexpression network of PTPRO through multiple databases and performed GO and KEGG enrichment analyses. The results demonstrated that PTPRO was involved in the regulation of multiple immune pathways. In addition, we analyzed whether PTPRO expression of LUAD regulate immune cell infiltration and the results demonstrated that PTPRO was closely related to the infiltration of various immune cells. Finally, we predicted LUAD sensitivity to chemotherapeutics and response to immunotherapy by PTPRO expression levels. The results showed that PTPRO expression level affect the sensitivity of various chemotherapeutic drugs and may be involved in the efficacy of immunotherapy. These results we obtained suggested that PTPRO is closely related to the prognosis and TIM of LUAD, which may be a potential immunotherapeutic target for LUAD.

HELLPAR/RRM2 axis related to HMMR as novel prognostic biomarker in gliomas

BACKGROUND

Gliomas are the most frequent type of central nervous system tumor, accounting for more than 70% of all malignant CNS tumors. Recent research suggests that the hyaluronan-mediated motility receptor (HMMR) could be a novel potential tumor prognostic marker. Furthermore, mounting data has highlighted the important role of ceRNA regulatory networks in a variety of human malignancies. The complexity and behavioural characteristics of HMMR and the ceRNA network in gliomas, on the other hand, remained unknown.

METHODS

Transcriptomic expression data were collected from TCGA, GTEx, GEO, and CGGA database.The relationship between clinical variables and HMMR was analyzed with the univariate and multivariate Cox regression. Kaplan-Meier method was used to assess OS. TCGA data are analyzed and processed, and the correlation results obtained were used to perform GO, GSEA, and ssGSEA. Potentially interacting miRNAs and lncRNAs were predicted by miRWalk and StarBase.

RESULTS

HMMR was substantially expressed in gliomas tissues compared to normal tissues. Multivariate analysis revealed that high HMMR expression was an independent predictive predictor of OS in TCGA and CGGA. Functional enrichment analysis found that HMMR expression was associated with nuclear division and cell cycle. Base on ssGSEA analysis, The levels of HMMR expression in various types of immune cells differed significantly. Bioinformatics investigation revealed the HEELPAR-hsa-let-7i-5p-RRM2 ceRNA network, which was linked to gliomas prognosis. And through multiple analysis, the good predictive performance of HELLPAR/RRM2 axis for gliomas patients was confirmed.

CONCLUSION

This study provides multi-layered and multifaceted evidence for the importance of HMMR and establishes a HMMR-related ceRNA (HEELPAR-hsa-let-7i-5p-RRM2) overexpressed network related to the prognosis of gliomas.

Secreted proteins MDK, WFDC2, and CXCL14 as candidate biomarkers for early diagnosis of lung adenocarcinoma

BACKGROUND

Early diagnosis of lung adenocarcinoma (LUAD), one of the most common types of lung cancer, is very important to improve the prognosis of patients. The current methods can't meet the requirements of early diagnosis. There is a pressing need to identify novel diagnostic biomarkers. Secretory proteins are the richest source for biomarker research. This study aimed to identify candidate secretory protein biomarkers for early diagnosis of LUAD by integrated bioinformatics analysis and clinical validation.

METHODS

Differentially expressed genes (DEGs) of GSE31210, gene expression data of early stage of LUAD, were analyzed by GEO2R. Upregulated DEGs predicted to encode secreted proteins were obtained by taking the intersection of the DEGs list with the list of genes encoding secreted proteins predicted by the majority decision-based method (MDSEC). The expressions of the identified secreted proteins in the lung tissues of early-stage LUAD patients were further compared with the healthy control group in mRNA and protein levels by using the UALCAN database (TCGA and CPTAC). The selected proteins expressed in plasma were further validated by using Luminex technology. The diagnostic value of the screened proteins was evaluated by receiver operating characteristic (ROC) analysis. Cell counting kit-8 assay was carried out to investigate the proliferative effects of these screened proteins.

RESULTS

A total of 2183 DEGs, including 1240 downregulated genes and 943 upregulated genes, were identified in the GSE31210. Of the upregulated genes, 199 genes were predicted to encode secreted proteins. After analysis using the UALCAN database, 16 molecules were selected for further clinical validation. Plasma concentrations of three proteins, Midkine (MDK), WAP four-disulfide core domain 2 (WFDC2), and C-X-C motif chemokine ligand 14 (CXCL14), were significantly higher in LUAD patients than in healthy donors. The area under the curve values was 0.944, 0.881, and 0.809 for MDK, WFDC2, and CXCL14, 0.962 when combined them. Overexpression of the three proteins enhanced the proliferation activity of A549 cells.

CONCLUSIONS

MDK, WFDC2, and CXCL14 were identified as candidate diagnostic biomarkers for early-stage LUAD and might also play vital roles in tumorigenesis.

Wnt signaling pathway-derived score for predicting therapeutic resistance and tumor microenvironment in lung adenocarcinoma

Background: Lung adenocarcinoma (LUAD) is the most common subtype of lung cancer. Due to tumor heterogeneity, understanding the pathological mechanism of tumor progression helps to improve the diagnosis process and clinical treatment strategies of LUAD patients. Methods: The transcriptome pattern, mutant expression and complete clinical information were obtained from the cancer genome atlas (TCGA) database and microarray data from gene expression omnibus (GEO) database. Firstly, we used single sample Gene Set Enrichment Analysis (ssGSEA) to estimate the activation of Wnt signaling pathway in each sample. Consensus clustering algorithm was used to classify LUAD samples into different subgroups according to the transcription patterns of 152 Wnt signaling pathway related genes. Then, ESTIMATE, ssGSEA and Gene Set Variation Analysis (GSVA) algorithms were used to assess the biological pathways and immunocytes infiltration between different subtypes. LASSO-COX algorithm was conducted to construct prognostic model. Kaplan-Meier and multivariate Cox analysis were performed to evaluate the predictive performance of risk model. Gene features were further confirmed using external datasets. Finally, we conducted vitro assay for validating hub gene (LEF1). Results: Based on the transcription patterns of 152 Wnt signaling pathway related genes, four different subtypes of LUAD patients were screened out by consensus clustering algorithm. Subsequently, it was found that patients with cluster A and B had massive immunocytes infiltration, and the survival rate of patients with cluster B was better than that of other subgroups. According to the coefficients in the LASSO- Cox model and the transcriptome patterns of these 18 genes, the risk score was constructed for each sample. The degree of malignancy of LUAD patients with high-risk subgroup was remarkable higher than that of patients with low-risk subgroup (p < 0.001). Subsequently, five top prognostic genes (AXIN1, CTNNB1, LEF1, FZD2, FZD4.) were screened, and their expression values were different between cancer and normal tissues. FZD2 and LEF1 were negatively related to ImmunoScore, and AXIN1 was negatively related to ImmunoScore. The significant correlation between LUAD patient risk score and overall survival (OS) was verified in external datasets. In the A549 cell line, knockdown of LEF1 can reduce the invasive and proliferation ability of LUAD cells. Conclusion: A innovative 18 genes predictive feature based on transcriptome pattern was found in patients with lung adenocarcinoma. These investigations further promote the insight of the prognosis of lung adenocarcinoma and may contribute to disease management at risk stratification.

Development of a peripheral blood transcriptomic gene signature to predict bronchopulmonary dysplasia

Bronchopulmonary dysplasia (BPD) is the most common lung disease of extreme prematurity, yet mechanisms that associate with or identify neonates with increased susceptibility for BPD are largely unknown. Combining artificial intelligence with gene expression data is a novel approach that may assist in better understanding mechanisms underpinning chronic lung disease and in stratifying patients at greater risk for BPD. The objective of this study is to develop an early peripheral blood transcriptomic signature that can predict preterm neonates at risk for developing BPD. Secondary analysis of whole blood microarray data from 97 very low birth weight neonates on day of life 5 was performed. BPD was defined as positive pressure ventilation or oxygen requirement at 28 days of age. Participants were randomly assigned to a training (70%) and testing cohort (30%). Four gene-centric machine learning models were built, and their discriminatory abilities were compared with gestational age or birth weight. This study adheres to the transparent reporting of a multivariable prediction model for individual prognosis or diagnosis (TRIPOD) statement. Neonates with BPD (n = 62 subjects) exhibited a lower median gestational age (26.0 wk vs. 30.0 wk, P < 0.01) and birth weight (800 g vs. 1,280 g, P < 0.01) compared with non-BPD neonates. From an initial pool (33,252 genes/patient), 4,523 genes exhibited a false discovery rate (FDR) <1%. The area under the receiver operating characteristic curve (AUC) for predicting BPD utilizing gestational age or birth weight was 87.8% and 87.2%, respectively. The machine learning models, using a combination of five genes, revealed AUCs ranging between 85.8% and 96.1%. Pathways integral to T cell development and differentiation were associated with BPD. A derived five-gene whole blood signature can accurately predict BPD in the first week of life.

Circ_0006646 Accelerates the Growth and Metastasis of Cervical Cancer by Elevating RRM2 Through miR-758-3p

Cervical cancer (CC) is the fourth most common cancer in women, and circular RNAs (circRNAs) have been shown to regulate CC development. However, the role of circ_0006646 in CC progression is still unclear. The levels of circ_0006646, miR-758-3p, and ribonucleotide reductase regulatory subunit M2 (RRM2) were evaluated by quantitative real-time PCR. Cell proliferation was tested by cell counting kit 8 and 5-ethynyl-2'-deoxyuridine assays. Flow cytometry was used to test cell apoptosis. Migration and invasion were estimated by transwell assay. Western blot assay was performed to examine protein expression. Dual-luciferase reporter assay, RIP assay, and RNA pull down assay were used to analyze the connection between miR-758-3p and circ_0006646 or RRM2. Tumor growth was detected by in vivo experiments. Exosomes were isolated form CC patients and healthy controls. Circ_0006646 expression was elevated in CC cells, and its knockdown suppressed CC cell growth, migration, and invasion. MiR-758-3p was sponged by circ_0006646, and RRM2 was targeted by miR-758-3p. In addition, the effects of circ_0006646 depletion on CC cell progression were overturned by miR-758-3p inhibitor, and either RRM2 overexpression reversed those effects of miR-758-3p overexpression on CC cell progression. Circ_0006646 was highly expressed in the exosomes of CC patients. Circ_0006646 expedited CC cell growth and metastasis by regulating miR-758-3p/RRM2 axis, and exosomal circ_0006646 might be a potential diagnostic indicator of CC.