MicroRNA-326 impairs chemotherapy resistance in non small cell lung cancer by suppressing histone deacetylase SIRT1-mediated HIF1α and elevating VEGFA

MicroRNA‑373‑3p inhibits the proliferation and invasion of non‑small‑cell lung cancer cells by targeting the GAB2/PI3K/AKT pathway

MicroRNAs (miRNAs) were previously demonstrated to be involved in the pathogenesis of non-small-cell lung cancer (NSCLC); however, the roles of certain miRNAs in NSCLC remain to be elucidated. The present study aimed to investigate the functions of screened miRNAs in NSCLC and the potential mechanisms. First, expression profiles of miRNAs were downloaded from the Gene Expression Omnibus (dataset no. GSE29248) and the differentially expressed miRNAs were analyzed by bioinformatics methods. Reverse transcription-quantitative PCR was used to validate the differential expression of miR-373 in clinical samples. The association between miR-373 expression levels and clinicopathological characteristics was also investigated. To further examine how miR-373 mediates the emergence of NSCLC, western blot, Cell Counting Kit-8, cell invasion and wound-healing assays, as well as apoptosis detection and a luciferase assay were used. The results indicated significant downregulation of miR-373 in NSCLC tissues and its low expression was closely associated with the degree of differentiation, clinical stage and tumor size, and was indicative of an unfavorable prognosis for patients with NSCLC. A functional study indicated that overexpression of miR-373 inhibited the proliferation, promoted apoptosis, and suppressed invasion and migration of NSCLC cells. Bioinformatics prediction and functional assays suggested that Grb-associated binding protein 2 (GAB2) was a direct target of miR-373. In addition, GAB2 was found to be significantly upregulated in NSCLC tissues, and clinically, miR-373 was negatively associated with GAB2. Furthermore, overexpression of GAB2 blocked the tumor suppressive effects of miR-373 on NSCLC cells. Mechanistically, miR-373 mimics were able to reduce the expression of GAB2 and subsequently decrease the phosphorylation level of AKT and mTOR protein. The present results indicate that miR-373 exerts its anti-tumor effects in NSCLC cells by targeting the GAB2/PI3K/AKT pathway, suggesting that miR-373 may be a potential therapeutic target in NSCLC.

SIRT1 Promotes Cisplatin Resistance in Bladder Cancer via Beclin1 Deacetylation-Mediated Autophagy

Autophagy-dependent cisplatin resistance poses a challenge in bladder cancer treatment. SIRT1, a protein deacetylase, is involved in autophagy regulation. However, the precise mechanism through which SIRT1 mediates cisplatin resistance in bladder cancer via autophagy remains unclear. In this study, we developed a cisplatin-resistant T24/DDP cell line to investigate this mechanism. The apoptosis rate and cell viability were assessed using flow cytometry and the CCK8 method. The expression levels of the relevant RNA and protein were determined using RT-qPCR and a Western blot analysis, respectively. Immunoprecipitation was utilized to validate the interaction between SIRT1 and Beclin1, as well as to determine the acetylation level of Beclin1. The findings indicated the successful construction of the T24/DDP cell line, which exhibited autophagy-dependent cisplatin resistance. Inhibiting autophagy significantly reduced the drug resistance index of these cells. The T24/DDP cell line showed a high SIRT1 expression level. The overexpression of SIRT1 activated autophagy, thereby further promoting cisplatin resistance in the T24/DDP cell line. Conversely, inhibiting autophagy counteracted the cisplatin-resistance-promoting effects of SIRT1. Silencing SIRT1 led to increased acetylation of Beclin1, the inhibition of autophagy, and a reduction in the cisplatin resistance of the T24/DDP cell line. Introducing a double mutation (lysine 430 and 437 to arginine, 2KR) in Beclin-1 inhibited acetylation and activated autophagy, effectively reversing the decreased cisplatin resistance resulting from SIRT1 silencing. In summary, our study elucidated that SIRT1 promotes cisplatin resistance in human bladder cancer T24 cells through Beclin1-deacetylation-mediated autophagy activation. These findings suggest a potential new strategy for reversing cisplatin resistance in bladder cancer.

Composition of Conditioned Media from Radioresistant and Chemoresistant Cancer Cells Reveals miRNA and Other Secretory Factors Implicated in the Development of Resistance

Resistance to chemo- or radiotherapy is the main obstacle to consistent treatment outcomes in oncology patients. A deeper understanding of the mechanisms driving the development of resistance is required. This review focuses on secretory factors derived from chemo- and radioresistant cancer cells, cancer-associated fibroblasts (CAFs), mesenchymal stem cells (MSCs), and cancer stem cells (CSCs) that mediate the development of resistance in unexposed cells. The first line of evidence considers the experiments with conditioned media (CM) from chemo- and radioresistant cells, CAFs, MSCs, and CSCs that elevate resistance upon the ionizing radiation or anti-cancer drug exposure of previously untreated cells. The composition of CM revealed factors such as circular RNAs; interleukins; plasminogen activator inhibitor; and oncosome-shuttled lncRNAs, mRNAs, and miRNAs that aid in cellular communication and transmit signals inducing the chemo- and radioresistance of sensitive cancer cells. Data, demonstrating that radioresistant cancer cells become resistant to anti-neoplastic drug exposure and vice versa, are also discussed. The mechanisms driving the development of cross-resistance between chemotherapy and radiotherapy are highlighted. The secretion of resistance-mediating factors to intercellular fluid and blood brings attention to its diagnostic potential. Highly stable serum miRNA candidates were proposed by several studies as prognostic markers of radioresistance; however, clinical studies are needed to validate their utility. The ability to predict a treatment response with the help of the miRNA resistance status database will help with the selection of an effective therapeutic strategy. The possibility of miRNA-based therapy is currently being investigated with ongoing clinical studies, and such approaches can be used to alleviate resistance in oncology patients.

miRNAs and exosomal miRNAs in lung cancer: New emerging players in tumor progression and therapy response

Non-coding RNAs have shown key roles in cancer and among them, short RNA molecules are known as microRNAs (miRNAs). These molecules have length less than 25 nucleotides and suppress translation and expression. The functional miRNAs are produced in cytoplasm. Lung cancer is a devastating disease that its mortality and morbidity have undergone an increase in recent years. Aggressive behavior leads to undesirable prognosis and tumors demonstrate abnormal proliferation and invasion. In the present review, miRNA functions in lung cancer is described. miRNAs reduce/increase proliferation and metastasis. They modulate cell death and proliferation. Overexpression of oncogenic miRNAs facilitates drug resistance and radio-resistance in lung cancer. Tumor microenvironment components including macrophages and cancer-associated fibroblasts demonstrate interactions with miRNAs in lung cancer. Other factors such as HIF-1α, lncRNAs and circRNAs modulate miRNA expression. miRNAs have also value in the diagnosis of lung cancer. Understanding such interactions can pave the way for developing novel therapeutics in near future for lung cancer patients.

Regulation of tumorigenesis and ferroptosis in non-small cell lung cancer by a novel BBOX1-AS1/miR-326/PROM2 axis

Dysregulation of long non-coding RNAs (lncRNAs) is associated with the tumorigenesis and ferroptosis of non-small cell lung cancer (NSCLC). BBOX1 antisense RNA 1 (BBOX1-AS1) functions as an oncogenic driver in NSCLC. Here, we aim to investigate the regulation effect and underlying mechanism of BBOX1-AS1 in NSCLC progression and ferroptosis. RNA expression was detected by quantitative real-time PCR (qRT-PCR), and protein expression was measured by immunoblotting. Cell growth was assessed by CCK-8 and colony formation assays. Transwell assay was applied to evaluate cell invasion and migration. RNA pull-down and dual-luciferase reporter assays were applied to verify the relationship between miR-326 and BBOX1-AS1 or prominin 2 (PROM2). The role of BBOX1-AS1 in NSCLC tumorigenicity was also analyzed by xenograft assays. Silencing BBOX1-AS1 or PROM2 impeded NSCLC cell growth, migration, and invasion. Silencing BBOX1-AS1 induced cell apoptosis and ferroptosis. BBOX1-AS1 up-regulated PROM2 expression, and re-expression of PROM2 reversed the effects of BBOX1-AS1 depletion on cell malignant phenotypes and ferroptosis. BBOX1-AS1 post-transcriptionally modulated PROM2 expression by sponging miR-326. MiR-326 was validated as a mediator of BBOX1-AS1 in regulating NSCLC cell malignant phenotypes and ferroptosis. Additionally, BBOX1-AS1 deficiency in vivo resulted in the suppression of xenograft tumor growth. Together, our study defines a novel BBOX1-AS1/miR-326/PROM2 axis in regulating NSCLC malignant progression and ferroptosis, offering new evidence for the oncogenic role of BBOX1-AS1 in NSCLC. These findings may provide a basis for the future usage of targeting BBOX1-AS1 in NSCLC treatment.

The sirtuin family in health and disease

Sirtuins (SIRTs) are nicotine adenine dinucleotide(+)-dependent histone deacetylases regulating critical signaling pathways in prokaryotes and eukaryotes, and are involved in numerous biological processes. Currently, seven mammalian homologs of yeast Sir2 named SIRT1 to SIRT7 have been identified. Increasing evidence has suggested the vital roles of seven members of the SIRT family in health and disease conditions. Notably, this protein family plays a variety of important roles in cellular biology such as inflammation, metabolism, oxidative stress, and apoptosis, etc., thus, it is considered a potential therapeutic target for different kinds of pathologies including cancer, cardiovascular disease, respiratory disease, and other conditions. Moreover, identification of SIRT modulators and exploring the functions of these different modulators have prompted increased efforts to discover new small molecules, which can modify SIRT activity. Furthermore, several randomized controlled trials have indicated that different interventions might affect the expression of SIRT protein in human samples, and supplementation of SIRT modulators might have diverse impact on physiological function in different participants. In this review, we introduce the history and structure of the SIRT protein family, discuss the molecular mechanisms and biological functions of seven members of the SIRT protein family, elaborate on the regulatory roles of SIRTs in human disease, summarize SIRT inhibitors and activators, and review related clinical studies.

Circ-PGAM1 Enhances Matrine Resistance of Non-Small Cell Lung Cancer via the miR-326/CXCR5 Axis

Background: Circular RNAs (circ-RNAs) have been demonstrated to influence initiation, drug resistance, and metastasis of tumors. However, the effects of circular-phosphoglycerate mutase 1 (circ-PGAM1) on matrine resistance in nonsmall cell lung cancer (NSCLC) remain unknown. Materials and Methods: The reverse transcription-quantitative polymerase chain reaction (RT-qPCR) was used to determine gene expression. The terminal deoxynucleotidyl transferase dUTP nick end labeling (TUNEL) and cell colony formation assays were used to evaluate NSCLC apoptosis and cell proliferation after indicated treatments, respectively. Results: circ-PGAM1 was upregulated in human NSCLC cell lines (H1299 and A549) compared with the human normal lung epithelial (BEAS-2B) cells. circ-PGAM1 overexpression reversed the matrine treatment-induced inhibition on proliferation of NSCLC cells (A549 and H1299) and rescued the matrine treatment-stimulated apoptosis of these cells. miR-326 was demonstrated to interact with circ-PGAM1. circ-PGAM1 knockdown enhanced the antitumor effect of matrine on NSCLC cell proliferation and apoptosis, which was reversed by miR-326 inhibition. The authors also identified CXCR5 as a key downstream target of miR-326 in A549 cells. Conclusions: circ-PGAM1 enhances matrine resistance of NSCLC cells through the miR-326/CXCR5 axis. The authors' findings provide new insights into NSCLC-targeted therapy.

Upregulation of CCNB2 and Its Perspective Mechanisms in Cerebral Ischemic Stroke and All Subtypes of Lung Cancer: A Comprehensive Study

Cyclin B2 (CCNB2) belongs to type B cell cycle family protein, which is located on chromosome 15q22, and it binds to cyclin-dependent kinases (CDKs) to regulate their activities. In this study, 103 high-throughput datasets related to all subtypes of lung cancer (LC) and cerebral ischemic stroke (CIS) with the data of CCNB2 expression were collected. The analysis of standard mean deviation (SMD) and summary receiver operating characteristic (SROC) reflecting expression status demonstrated significant up-regulation of CCNB2 in LC and CIS (Lung adenocarcinoma: SMD = 1.40, 95%CI [0.98–1.83], SROC = 0.92, 95%CI [0.89–0.94]. Lung squamous cell carcinoma: SMD = 2.56, 95%CI [1.64–3.48]. SROC = 0.97, 95%CI [0.95–0.98]. Lung small cell carcinoma: SMD = 3.01, 95%CI [2.01–4.01]. SROC = 0.98, 95%CI [0.97–0.99]. CIS: SMD = 0.29, 95%CI [0.05–0.53], SROC = 0.68, 95%CI [0.63–0.71]). Simultaneously, protein-protein interaction (PPI) analysis indicated that CCNB2 is the hub molecule of crossed high-expressed genes in CIS and LC. Through Multiscale embedded gene co-expression network analysis (MEGENA), a gene module of CIS including 76 genes was obtained and function enrichment analysis of the CCNB2 module genes implied that CCNB2 may participate in the processes in the formation of CIS and tissue damage caused by CIS, such as “cell cycle,” “protein kinase activity,” and “glycosphingolipid biosynthesis.” Afterward, via single-cell RNA-seq analysis, CCNB2 was found up-regulated on GABAergic neurons in brain organoids as well as T cells expressing proliferative molecules in LUAD. Concurrently, the expression of CCNB2 distributed similarly to TOP2A as a module marker of cell proliferation in cell cluster. These findings can help in the field of the pathogenesis of LC-related CIS and neuron repair after CIS damage.

hsa_circ_0139402 Promotes Bladder Cancer Progression by Regulating hsa-miR-326/PAX8 Signaling

Background

Bladder cancer (BC) is a malignant and common malignant tumors. However, the prognosis of most patients with bladder cancer is still poor, and it is particularly important to identify early tumor diagnostic and treatment targets.

Materials and Methods

High-throughput sequencing was used to evaluate the expression level of circRNA in bladder cancer tissue. MTT assay, wound healing assay, and transwell assay were used to detect the cancer cells' proliferation, migration, and invasion affected by hsa_circ_0139402. The possible miRNA targets of hsa_circ_0139402 and downstream genes were detected by bioinformatics methods and dual-luciferase reporting experiment. FISH was used to observe their interaction.

Results

High-throughput sequencing result showed that the expression of hsa_circ_0139402 was highest in BC tissues and increased in metastatic tissues compared to that of nonmetastatic tissues. MTT assay, wound healing assay, and transwell assay revealed that sh-hsa_circ_0139402 could suppress BC cells' proliferation, invasion, and migration. Bioinformatics analysis, dual-luciferase reporter, and RIP assay showed that hsa_circ_0139402 can bind to hsa-miR-326, and PAX8 is a direct target of hsa-miR-326 in BC cell. Further, cytological studies found that hsa_circ_0139402 enhances BC cells' proliferation, migration, and invasion by targeting PAX8 via hsa-miR-326.

Conclusion

hsa_circ_0139402 plays a oncogene in BC and that can effectively promote cell proliferation, migration, invasion, and EMT by targeting Paired Box Protein Pax-8 (PAX8) via hsa-miR-326 and provides a potential therapeutic target for BC patients.

Upregulating microRNA-373-3p promotes apoptosis and inhibits metastasis of hepatocellular carcinoma cells

Hepatocellular carcinoma (HCC) is one of the most prevalent malignancies in the digestive system. Abnormal miR-373-3p and TFAP4 expressions are critical in many malignant tumors, but it is unclear whether they work in the context of HCC. qRT-PCR measured miR-373-3p expression in HCC tissues and adjacent normal tissues. Flow cytometry and Western blot analyzed cell apoptosis. EMT, Transwell, and wound healing assay examined HCC cell migration and EMT, respectively. Western blot determined the profile of TFAP4/PI3K/AKT. IHC detected Ki67, E-cadherin, and vimentin in the tumor tissues. Moreover, the downstream target of miR-373-3p was predicted using the database. Dual luciferase activity assay and RIP verified the binding correlation between TFAP4 and miR-373-3p. In HCC tissues and cell lines, miR-373-3p was downregulated, and its overexpression stepped up HCC cell apoptosis and suppressed migration and EMT. Furthermore, miR-373-3p overexpression elevated Bax and caspase 3 expressions and attenuated Bcl2’s level. A xenograft tumor experiment in nude mice unveiled that miR-373-3p overexpression dampened tumor growth and proliferation. miR-373-3p cramped PI3K/AKT pathway activation. miR-373-3p negatively modulated TFAP4, and TFAP4 overexpression inverted miR-373-3p-mediated anti-tumor effects. Additionally, TFAP4 enhanced IGF1 expression, and promoted IGF1R-PI3K/AKT pathway activation. Collectively, miR-373-3p functions as an anti-tumor gene in HCC by inhibiting TFAP4/PI3K/AKT pathway.

Circ_0017639 facilitates proliferative, migratory, and invasive potential of non-small cell lung cancer (NSCLC) cells via PI3K/AKT signaling pathway

Non-small cell lung cancer (NSCLC) has increased morbidity and mortality rate worldwide. The current NSCLS therapies are associated with poor outcomes and need further improvement. CircRNAs were shown to regulate NSCLC progression. However, little is known re garding the functions and mechanisms of circ_0017639 in NSCLC, which requires further extensive studies. The circ_0017639 expression in NSCLC tissues and cell lines was evaluated via qRT-RCR. Moreover, using ectopic plasmid incorporation and shRNA assays, we analyzed the circ_0017639-mediated cellular proliferative, migratory and invasive processes in NSCLC cell lines, using CCK-8, EdU, and transwell assays. Furthermore, the core proteins (p-PI3K, PI3K, p-AKT, and AKT) levels of the PI3K/AKT signaling cascade were investigated via immunoblotting. Finally, we tested the functional role of circ_0017639 by examining its regulation of xenograft tumor growths in nude mice in vivo. Circ_0017639 expression was remarkably high in the NSCLC tissues and cell lines. The transfection experiments showed that circ_0017639 overexpression was able to promote proliferative, migratory, and invasive properties of NSCLC cells, while sh-circ_0017639 showed opposing effects. We further showed that circ_0017639 knockdown suppressed the cellular development via PI3K/AKT cascade inactivation. Additionally, in-vivo experiment in nude mice demonstrated that sh-circ_0017639 could reduce the tumor growth of NSCLC. Circ_0017639 may promote the development of NSCLC by accelerating NSCLC metastasis through stimulating the PI3K/AKT cascade.