Downregulation of LINC01508 contributes to cisplatin resistance in ovarian cancer via the regulation of the Hippo-YAP pathway

Proto-oncogene c-Myb potentiates cisplatin resistance of ovarian cancer cells by downregulating lncRNA NKILA and modulating cancer stemness and LIN28A-let7 axis

Ovarian cancer is a major gynecological cancer that has poor prognosis associated mainly to its late diagnosis. Cisplatin is an FDA approved ovarian cancer therapy and even though the therapy is initially promising, the patients mostly progress to resistance against cisplatin. The underlying mechanisms are complex and not very clearly understood. Using two different paired cell lines representing cisplatin-sensitive and the cisplatin-resistant ovarian cancer cells, the ES2 and the A2780 parental and cisplatin-resistant cells, we show an elevated proto-oncogene c-Myb in resistant cells. We further show down-regulated lncRNA NKILA in resistant cells with its de-repression in resistant cells when c-Myb is silenced. NKILA negatively correlates with cancer cell and invasion but has no effect on cellular proliferation or cell cycle. C-Myb activates NF-κB signaling which is inhibited by NKILA. The cisplatin resistant cells are also marked by upregulated stem cell markers, particularly LIN28A and OCT4, and downregulated LIN28A-targeted let-7 family miRNAs. Whereas LIN28A and downregulated let-7s individually de-repress c-Myb-mediated cisplatin resistance, the ectopic expression of let-7s attenuates LIN28A effects, thus underlying a c-Myb-NKILA-LIN28A-let-7 axis in cisplatin resistance of ovarian cancer cells that needs to be further explored for therapeutic intervention.

Targeting Hippo signaling in cancer: novel perspectives and therapeutic potential

As highly conserved among diverse species, Hippo signaling pathway regulates various biological processes, including development, cell proliferation, stem cell function, tissue regeneration, homeostasis, and organ size. Studies in the last two decades have provided a good framework for how these fundamental functions of Hippo signaling are tightly regulated by a network with numerous intracellular and extracellular factors. The Hippo signaling pathway, when dysregulated, may lead to a wide variety of diseases, especially cancer. There is growing evidence demonstrating that dysregulated Hippo signaling is closely associated with tumorigenesis, cancer cell invasion, and migration, as well as drug resistance. Therefore, the Hippo pathway is considered an appealing therapeutic target for the treatment of cancer. Promising novel agents targeting the Hippo signaling pathway for cancers have recently emerged. These novel agents have shown antitumor activity in multiple cancer models and demonstrated therapeutic potential for cancer treatment. However, the detailed molecular basis of the Hippo signaling-driven tumor biology remains undefined. Our review summarizes current advances in understanding the mechanisms by which Hippo signaling drives tumorigenesis and confers drug resistance. We also propose strategies for future preclinical and clinical development to target this pathway.

Identification of lncRNAs Deregulated in Epithelial Ovarian Cancer Based on a Gene Expression Profiling Meta-Analysis

Epithelial ovarian cancer (EOC) is one of the deadliest gynecological cancers worldwide, mainly because of its initially asymptomatic nature and consequently late diagnosis. Long non-coding RNAs (lncRNA) are non-coding transcripts of more than 200 nucleotides, whose deregulation is involved in pathologies such as EOC, and are therefore envisaged as future biomarkers. We present a meta-analysis of available gene expression profiling (microarray and RNA sequencing) studies from EOC patients to identify lncRNA genes with diagnostic and prognostic value. In this meta-analysis, we include 46 independent cohorts, along with available expression profiling data from EOC cell lines. Differential expression analyses were conducted to identify those lncRNAs that are deregulated in (i) EOC versus healthy ovary tissue, (ii) unfavorable versus more favorable prognosis, (iii) metastatic versus primary tumors, (iv) chemoresistant versus chemosensitive EOC, and (v) correlation to specific histological subtypes of EOC. From the results of this meta-analysis, we established a panel of lncRNAs that are highly correlated with EOC. The panel includes several lncRNAs that are already known and even functionally characterized in EOC, but also lncRNAs that have not been previously correlated with this cancer, and which are discussed in relation to their putative role in EOC and their potential use as clinically relevant tools.

Transfer RNA-derived small RNAs (tsRNAs) sequencing revealed a differential expression landscape of tsRNAs between glioblastoma and low-grade glioma

BACKGROUND

Glioblastomas (GBMs) are the most lethal brain cancer with a median survival rate of fewer than 15 months. Both clinical and biological features of GBMs are largely different from those of low-grade gliomas (LGs), but the reasons for this intratumoral heterogeneity are not entirely clear. Transfer RNA (tRNA)-derived small RNAs (tsRNAs) were derived from tRNA precursors and mature tRNA, referring to the specific cleavage of tRNAs by dicer and angiogenin (ANG) in particular cells or tissues or under certain conditions such as stress and hypoxia. With the characteristics of wide expression and high stability, tsRNAs could be used as favorable biomarkers for diagnosis, treatment, and prognosis prediction of the tumor, viral infection, neurological as well as other systemic diseases. In this study, we have compared the differential expressed tsRNAs between GBMs and LGs, so as to investigate the possible pathogenic molecules and provide references for discovering novel nucleic acid drugs in future studies.

METHODS

Fresh tumor tissues of patients that were diagnosed as GBMs (4 cases) and LGs (5 cases) at the First Affiliated Hospital of Wenzhou Medical University from 2019.05 to 2021.01 were collected. The tsRNAs' levels were analyzed and compared through high-throughput sequencing, candidate tsRNAs were chosen according to the expression level, and the expression of the candidate tsRNAs was validated through qPCR. Finally, the potential targets were imputed using the Miranda and TargetScan databases, and possible biological functions of the differentially expressed (DE) tsRNAs' targets were enriched based on GO and KEGG databases.

RESULTS

A total of 4 GBMs and 5 LGs patients were enrolled in the current study. High-throughput sequencing showed that 186 tsRNAs were expressed in two groups, over them, 43 tsRNAs were unique to GBMs, and 24 tsRNAs were unique to LGs. A total of 9 tsRNAs were selected as candidate tsRNAs according to the tsRNA expression level, among which 6 tsRNAs were highly expressed in GBMs and 3 tsRNAs were low expressed in GBMs. qPCR verification further demonstrated that 5 tsRNAs were significantly up-regulated and 1 tsRNA was significantly down-regulated in GBMs: tRF-1-32-chrM.Lys-TTT (p=0.00118), tiRNA-1-33-Gly-GCC-1 (p=0.00203), tiRNA-1-33-Gly-CCC-1 (p=0.00460), tRF-1-31-His-GTG-1 (p=0.00819), tiRNA-1-33-Gly-GCC-2-M3 (p=0.01032), and tiRNA-1-34-Lys-CTT-1-M2 (p=0.03569). Enrichment analysis of the qPCR verified DE tsRNAs showed that the 5 up-regulated tsRNAs seemed to be associated with axon guidance, pluripotent stem cells regulation, nucleotide excision repair, Hippo signaling pathway, and cancer-related pathways, while the down-regulated tsRNA (tRF-1-32-chrM.Lys-TTT) was associated with oocyte meiosis and renin secretion.

CONCLUSION

The tsRNAs were differentially expressed in tumor tissues between GBMs and LGs, especially tRF-1-32-chrM.Lys-TTT, tiRNA-1-33-Gly-GCC-1, tiRNA-1-33-Gly-CCC-1, tRF-1-31-His-GTG-1, tiRNA-1-33-Gly-GCC-2-M3, and tiRNA-1-34-Lys-CTT-1-M2. These tsRNAs seemed to be associated with nucleotide excision repair, Hippo signaling, and cancer-related pathways. This may be the main reason for the differences in clinical characteristics between GBMs and LGs, which may provide a certain theoretical basis for further functional research and development of related nucleic acid drugs.

CONCLUSION

The tsRNAs were differentially expressed in tumor tissues between GBMs and LGs, especially tRF-1-32-chrM.Lys-TTT, tiRNA-1-33-Gly-GCC-1, tiRNA-1-33-Gly-CCC-1, tRF-1-31-His-GTG-1, tiRNA-1-33-Gly-GCC-2-M3, and tiRNA-1-34-Lys-CTT-1-M2. These tsRNAs seemed to be associated with nucleotide excision repair, Hippo signaling, and cancer-related pathways. This may be the main reason for the differences in clinical characteristics between GBMs and LGs, which may provide a certain theoretical basis for further functional research and development of related nucleic acid drugs.

Molecular Mechanism of Curcumin Derivative on YAP Pathway against Ovarian Cancer

The purpose of this study is to study the effect of curcumin derivative WZ10 on the proliferation, invasion and apoptosis of ovarian cancer OVCAR3 cells, and to explore its mechanism. MTT assay was used to detect the effect of WZ10 on the proliferation of ovarian cancer OVCAR3 cells; Annexin V/PI double staining flow cytometry was used to detect the effect of WZ10 on cell apoptosis; Transwell method was used to detect the effect of WZ10 on cell invasiveness; Western blot was used to investigate the effect of WZ10 Mechanisms affecting OVCAR3 activity in ovarian cancer in vitro. Our results show that WZ10 treatment could significantly inhibit the proliferation and invasion of OVCAR3 cells, induce apoptosis of OVCAR3 cells in a dose-dependent manner. After knockdown of Hippo expression with sh-RNA, further combined treatment with WZ10 had no significant image on ovarian cancer OVCAR3 cells. In conclusion: WZ10 can significantly inhibit the proliferation of OVCAR3 cells, reduce cell invasion and proliferation by downregulating the activation of Hippo-YAP pathway, and induce cell apoptosis.

Transcriptome of Lung Cancer Cells Resistant to the Cytotoxic Activity of Macrophages

The role of the immune system in tumor progression has been the subject of research for more than 100 years since Paul Ehrlich hypothesized that the presence of the immune system limits the occurrence of cancer. One of the mechanisms hindering the initiation and progression of the tumor is the cytotoxic activity of macrophages; however, in some cases, it is not sufficient to control tumorigenesis. This may be due to both the development of resistance of tumor cells to the antitumor activity of macrophages and the development of a tolerant phenotype of macrophages that do not have sufficient antitumor activity. In this work, the lung cancer cells resistant to the cytotoxic action of macrophages were obtained and characterized for the first time, and the genes associated with the observed changes were identified. Understanding the mechanisms of resistance of tumor cells to the cytotoxic activity of macrophages and the peculiarities of its manifestation in a tumor environment is critically important for improving the effectiveness of the existing methods of cancer treatment and developing novel methods for tumor immunotherapy.

Identification of a Novel Long Non-coding RNA, lnc-ATMIN-4:2, and its Clinicopathological and Prognostic Significance in Advanced Gastric Cancer

BACKGROUND/AIM

Long non-coding RNAs (lncRNAs) are emerging as significant regulators of gene expression and a novel promising biomarker for cancer diagnosis and prognosis. This study identified a novel, differentially expressed lncRNA in advanced gastric cancer (AGC), Inc-ATMIN-4:2, and evaluated its clinicopathological and prognostic significance.

PATIENTS AND METHODS

Whole transcriptome sequencing was performed to identify differentially expressed lncRNAs in AGC tissue samples. We also analyzed lnc-ATMIN-4:2 expression in 317 patients with AGC using RNA in situ hybridization.

RESULTS

High (>30 dots) lnc-ATMIN-4:2 expression significantly correlated with younger age, poorly differentiated histology, diffuse type, deeper invasion depth, perineural invasion, lymph node metastasis, and higher stage group. In addition, high lnc-ATMIN-4:2 expression was significantly associated with worse overall survival in patients with AGC.

CONCLUSION

This study elucidated the significance of lncRNAs in AGC and indicated the value of lnc-ATMIN-4:2 expression as a predictive biomarker for the overall survival of patients with AGC.

Comprehensive Characterization of Immune Landscape Based on Tumor Microenvironment for Oral Squamous Cell Carcinoma Prognosis

Objective: This study aims to identify an immune-related signature to predict clinical outcomes of oral squamous cell carcinoma (OSCC) patients. Methods: Gene transcriptome data of both tumor and normal tissues from OSCC and the corresponding clinical information were downloaded from The Cancer Genome Atlas (TCGA). Tumor Immune Estimation Resource algorithm (ESTIMATE) was used to calculate the immune/stromal-related scores. The immune/stromal scores and associated clinical characteristics of OSCC patients were evaluated. Univariate Cox proportional hazards regression analyses, least absolute shrinkage, and selection operator (LASSO) and receiver operating characteristic (ROC) curve analyses were performed to assess the prognostic prediction capacity. Gene Set Enrichment Analysis (GSEA) and Gene Ontology (GO) function annotation were used to analysis the functions of TME-related genes. Results: Eleven predictor genes were identified in the immune-related signature and overall survival (OS) in the high-risk group was significantly shorter than in the low-risk group. An ROC analysis showed the TME-related signature could predict the total OS of OSCC patients. Moreover, GSEA and GO function annotation proved that immunity and immune-related pathways were mainly enriched in the high-risk group. Conclusions: We identified an immune-related signature that was closely correlated with the prognosis and immune response of OSCC patients. This signature may have important implications for improving the clinical survival rate of OSCC patients and provide a potential strategy for cancer immunotherapy.

Non-coding RNA in cancer drug resistance: Underlying mechanisms and clinical applications

Cancer is one of the most frequently diagnosed malignant diseases worldwide, posing a serious, long-term threat to patients’ health and life. Systemic chemotherapy remains the first-line therapeutic approach for recurrent or metastatic cancer patients after surgery, with the potential to effectively extend patient survival. However, the development of drug resistance seriously limits the clinical efficiency of chemotherapy and ultimately results in treatment failure and patient death. A large number of studies have shown that non-coding RNAs (ncRNAs), particularly microRNAs, long non-coding RNAs, and circular RNAs, are widely involved in the regulation of cancer drug resistance. Their dysregulation contributes to the development of cancer drug resistance by modulating the expression of specific target genes involved in cellular apoptosis, autophagy, drug efflux, epithelial-to-mesenchymal transition (EMT), and cancer stem cells (CSCs). Moreover, some ncRNAs also possess great potential as efficient, specific biomarkers in diagnosis and prognosis as well as therapeutic targets in cancer patients. In this review, we summarize the recent findings on the emerging role and underlying mechanisms of ncRNAs involved in cancer drug resistance and focus on their clinical applications as biomarkers and therapeutic targets in cancer treatment. This information will be of great benefit to early diagnosis and prognostic assessments of cancer as well as the development of ncRNA-based therapeutic strategies for cancer patients.

Nonalcoholic Fatty Liver Hepatocyte-Derived lncRNA MALAT1 Aggravates Pancreatic Cell Inflammation via the Inhibition of Autophagy by Upregulating YAP

Background

Acute pancreatitis (AP) is one of the most common gastrointestinal disorders, which causes death with a high mortality rate of about 30%. The study aims to identify whether the nonalcoholic fatty liver disease (NAFLD)-derived lncRNA MALAT1 participates in the inflammation of pancreatic cell and its potential mechanism.

Methods

The NAFLD cell model was constructed by treating HepG2 cells with FFA. The in vitro model of acute pancreatitis (AP) was established by the administration of caerulein on AR42J cells. MALAT1 and si-MALAT1 were transfected into pancreatic cells, and then exosomes were collected from the NAFLD cell model and then were cocultured with AR42J cells. Transmission electron microscopy was used to observe the morphology of exosomes. Oil Red O staining was applied to reveal the lipid deposition. The triglyceride, IL-6, and TNF-α levels were detected using ELISA. The MALAT1 level in exosomes was detected by qRT-PCR. The CD9, CD63, CD81, and CYP2E1, LC3II, and LC3I levels were detected by western blot.

Results

MALAT1 was upregulated in NAFLD-derived exosomes and increased the levels of IL-6 and TNF-α in pancreatic cells. NAFLD-derived exosomes inhibited YAP phosphorylation, decreased the levels of IL-6 and TNF-α, and reduced the ratio of LC3II/LC3I protein in pancreatic cells. Silencing MALAT1 significantly returned the inhibitory effect of NAFLD on hippo-YAP pathway. YAP1 signal transduction inhibitor CA3 reversed the decrease of LC3II/LC3I expression and the increase of IL-6 and TNF-α levels induced by MALAT1 in the AP cell model.

Conclusions

NAFLD-derived MALAT1 exacerbates pancreatic cell inflammation via inhibiting autophagy by upregulating YAP.

Long noncoding RNAs as therapeutic targets to overcome chemoresistance in ovarian cancer

Long noncoding RNAs (lncRNAs) have been characterized to play an essential role in ovarian tumorigenesis via controlling a variety of cellular processes, such as cell proliferation, invasion, apoptotic death, metastasis, cell cycle, migration, metabolism, immune evasion, and chemoresistance. The one obstacle for the therapeutic efficacy is due to the development of drug resistance in ovarian cancer patients. Therefore, in this review article, we describe the role of lncRNAs in chemoresistance in ovarian cancer. Moreover, we discuss the molecular mechanism of lncRNAs-involved drug resistance in ovarian cancer. We conclude that lncRNAs could be useful targets to overcome chemoresistance and improve therapeutic outcome in ovarian cancer patients.

A somatic mutation-derived LncRNA signatures of genomic instability predicts the prognosis and tumor microenvironment immune characters in hepatocellular carcinoma

BACKGROUND

Hepatocellular carcinoma (HCC) is an aggressive carcinoma with genome instability. Long non-coding RNAs (LncRNAs) have been functionally associated with genomic instability in cancers. However, the identification and prognostic value of lncRNAs related to genome instability have not been explored in hepatocellular carcinoma. In this study, we aim to identify a genomic instability-related lncRNA signature for predicting prognosis and the efficacy of immunotherapy in HCC patients.

METHODS

According to the somatic mutation and transcript data of 364 patients with HCC, we determined differentially expressed genome instability-related lncRNAs (GInLncRNAs). Gene ontology (GO) enrichment analyses and Kyoto Encyclopedia of genes and genomes enrichment analyses revealed the potential functions of genes co-expressed with those lncRNAs involved in cancer development and immune function. We further determined a genome instability-related lncRNA signature (GInLncSig) through Cox regression analysis and LASSO regression analysis. Thereafter, we performed correlation analyses with mutations, clinical stratification analyses, and survival analyses to evaluate GInLncSig predictive function. Subsequently, we construct a nomogram model for prognostic assessments of patients with HCC. Finally, we performed Immunocytes infiltration analysis, gene set enrichment analysis (ssGSEA) of immunity circle-associated pathways, and T cell-inflamed score to explore GInLncSig's potential value in guiding immunotherapy.

RESULTS

We identified 11 independent prognosis-associated GInLncRNAs (AC002511.2, LINC00501, LINC02055, LINC02714, LINC01508, LOC105371967, RP11_96A15.1, RP11_305F18.1, RP11_342M1.3, RP11_432J24.3, U95743.1) to construct a GInLncSig. According to the risk score calculated by GInLncSig, the high-risk group was characterized by a higher somatic mutation count, significantly poorer clinical prognosis, higher T cell-inflamed score, and specific tumor immune infiltration status compared to the low-risk group. Furthermore, we constructed a nomogram model to improve the reliability and clinical utility of predicting the prognosis of patients with HCC.

CONCLUSION

Our study established a reliable prognostic prediction signature that could be a tool for prognosis prediction and a promising predictive biomarker of immunotherapy in hepatocellular carcinoma.

Open Versus Minimally Invasive Radical Hysterectomy in Cervical Cancer: The CIRCOL Group Study

PURPOSE

To analyze the survival outcomes of patients in a Brazilian cohort who underwent minimally invasive surgery (MIS) compared with open surgery for early stage cervical cancer.

METHODS

A multicenter database was constructed, registering 1280 cervical cancer patients who had undergone radical hysterectomy from 2000 to 2019. For the final analysis, we included cases with a tumor ≤ 4 cm (stages Ia2 to Ib2, FIGO 2018) that underwent surgery from January 2007 to December 2017. Propensity score matching was also performed.

RESULTS

A total of 776 cases were ultimately analyzed, 526 of which were included in the propensity score matching analysis (open, n = 263; MIS, n = 263). There were 52 recurrences (9.9%), 28 (10.6%) with MIS and 24 (9.1%) with open surgery (p = 0.55); and 34 deaths were recorded, 13 (4.9%) and 21 (8.0%), respectively (p = 0.15). We noted a 3-year disease-free survival (DFS) rate of 88.2% and 90.3% for those who received MIS and open surgery, respectively (HR 1.32; 95% CI: 0.76-2.29; p = 0.31) and a 5-year overall survival (OS) rate of 91.8% and 91.1%, respectively (HR 0.80; 95% CI: 0.40-1.61; p = 0.53). There was no difference in 3-year DFS rates between open surgery and MIS for tumors ≤ 2 cm (95.7% vs. 90.8%; p = 0.16) or > 2 cm (83.9% vs. 85.4%; p = 0.77). Also, the 5-year OS between open surgery and MIS did not differ for tumors ≤ 2 cm (93.1% vs. 93.6%; p = 0.82) or > 2 cm (88.9% vs. 89.8%; p = 0.35).

CONCLUSIONS

Survival outcomes were similar between minimally invasive and open radical hysterectomy in this large retrospective multicenter cohort.