The identification of CRNDE, H19, UCA1 and HOTAIR as the key lncRNAs involved in oxaliplatin or irinotecan resistance in the chemotherapy of colorectal cancer based on integrative bioinformatics analysis

The role of HOTAIR in the modulation of resistance to anticancer therapy

Leading anti-tumour therapeutic strategies typically involve surgery and radiotherapy for locally advanced (non-metastatic) cancers, while hormone therapy, chemotherapy, and molecular targeted therapy are the current treatment options for metastatic cancer. Despite the initially high sensitivity rate to anticancer therapies, a large number of patients develop resistance, leading to a poor prognosis. The mechanisms related to drug resistance are highly complex, and long non-coding RNAs appear to play a crucial role in these processes. Among these, the lncRNA homeobox transcript antisense intergenic RNA (HOTAIR), widely implicated in cancer initiation and progression, likewise plays a significant role in anticancer drug resistance. It can modulate cell activities such as proliferation, apoptosis, hypoxia, autophagy, as well as epithelial-mesenchymal transition, thereby contributing to the development of resistant tumour cells. In this manuscript, we describe different mechanisms of antitumor drug resistance in which HOTAIR is involved and suggest its potential as a therapeutic predictive biomarker for the management of cancer patients.

Identification of expression profiles and prognostic value of RFCs in colorectal cancer

Colorectal cancer (CRC) ranks among the most prevalent cancers globally, with its incidence closely tied to DNA damage. The Replication Factor C (RFC) complexes comprises five protein subunits: RFC1, RFC2, RFC3, RFC4, and RFC5. These RFC complexes play crucial roles in DNA replication, repair pathways, activities post DNA damage, and ATP-dependent processes during DNA synthesis. However, the impact of RFC complexes proteins on CRC prognosis remains unclear. To explore this, we employed a computational analysis approach, utilizing platforms such as the DepMap portal, GEPIA, DAVID Bioinformatics for KEGG pathway analysis, Human Protein Atlas (HPA), STRING, and TIMER. Our results indicate that the mRNA levels of RFC1 and RFC5 were the least expressed among CRC cell lines compared to other RFC complex subunits. Notably, low RFC1 and RFC5 expression was correlated with poor prognosis in terms of CRC patients' overall survival (OS). Immunohistochemical results from the Human Protein Atlas demonstrated medium staining for RFC1, RFC2, and RFC5 in CRC tissues. Furthermore, the low expression of RFC1 and RFC5 showed a significant correlation with high expression levels of miR-26a-5p and miR-636, impacting cell proliferation through mismatch repair, DNA replication, and the nucleotide excision repair pathway. Although the precise functions of RFC1 in cancer are still unknown, our findings suggest that the small-molecule single target, CHEMBL430483, and multiple target molecules could be potential treatments for CRC. In conclusion, the elevated expression of miR-26a-5p and miR-636 targeting RFC1 and RFC5 expression holds promise as a potential biomarker for early-stage CRC detection. These insights provide novel directions and strategies for CRC therapies.

Long non-coding RNAs in drug resistance across the top five cancers: Update on their roles and mechanisms

Cancer drug resistance stands as a formidable obstacle in the relentless fight against the top five prevalent cancers: breast, lung, colorectal, prostate, and gastric cancers. These malignancies collectively account for a significant portion of cancer-related deaths worldwide. In recent years, long non-coding RNAs (lncRNAs) have emerged as pivotal players in the intricate landscape of cancer biology, and their roles in driving drug resistance are steadily coming to light. This comprehensive review seeks to underscore the paramount significance of lncRNAs in orchestrating resistance across a spectrum of different cancer drugs, including platinum drugs (DDP), tamoxifen, trastuzumab, 5-fluorouracil (5-FU), paclitaxel (PTX), and Androgen Deprivation Therapy (ADT) across the most prevalent types of cancer. It delves into the multifaceted mechanisms through which lncRNAs exert their influence on drug resistance, shedding light on their regulatory roles in various facets of cancer biology. A comprehensive understanding of these lncRNA-mediated mechanisms may pave the way for more effective and personalized treatment strategies, ultimately improving patient outcomes in these challenging malignancies.

Decreased expression of H19/miR-675 ameliorates hypoxia-induced oxaliplatin resistance in colorectal cancer

Hypoxic microenvironment, a hallmark of solid tumors, contributes to chemoresistance, and long noncoding (lnc) RNAs are involved in hypoxia-induced drug resistance. However, the role of lncRNAs in hypoxic tumor chemotherapy resistance remains unclear. Here, we aimed to elucidate the effects of lncRNAs in hypoxia-mediated resistance in colorectal cancer (CRC), as well as the underlying mechanisms. The results indicated that the expression of lncRNA H19 was enhanced in hypoxia- or oxaliplatin-treated CRC cells; moreover, H19 contributed to drug resistance in CRC cells both in vitro and in vivo. Mechanistically, H19 was noted to act as a competitive endogenous RNA of miR-675-3p to regulate epithelial-mesenchymal transition (EMT). Notably, an miR-675-3p mimic could attenuate the effects of H19 deficiency in CRC cells with hypoxia-induced chemoresistance. In conclusion, H19 downregulation may counteract hypoxia-induced chemoresistance by sponging miR-675-3p to regulate EMT; as such, the H19/miR-675-3p axis might be a promising therapeutic target for drug resistance in CRC.

Unlocking the predictive potential of long non-coding RNAs: a machine learning approach for precise cancer patient prognosis

The intricate web of cancer biology is governed by the active participation of long non-coding RNAs (lncRNAs), playing crucial roles in cancer cells' proliferation, migration, and drug resistance. Pioneering research driven by machine learning algorithms has unveiled the profound ability of specific combinations of lncRNAs to predict the prognosis of cancer patients. These findings highlight the transformative potential of lncRNAs as powerful therapeutic targets and prognostic markers. In this comprehensive review, we meticulously examined the landscape of lncRNAs in predicting the prognosis of the top five cancers and other malignancies, aiming to provide a compelling reference for future research endeavours. Leveraging the power of machine learning techniques, we explored the predictive capabilities of diverse lncRNA combinations, revealing their unprecedented potential to accurately determine patient outcomes.

Oxaliplatin related lncRNAs prognostic models predict the prognosis of patients given oxaliplatin-based chemotherapy

BACKGROUND

Oxaliplatin-based chemotherapy is the first-line treatment for colorectal cancer (CRC). Long noncoding RNAs (lncRNAs) have been implicated in chemotherapy sensitivity. This study aimed to identify lncRNAs related to oxaliplatin sensitivity and predict the prognosis of CRC patients underwent oxaliplatin-based chemotherapy.

METHODS

Data from the Genomics of Drug Sensitivity in Cancer (GDSC) was used to screen for lncRNAs related to oxaliplatin sensitivity. Four machine learning algorithms (LASSO, Decision tree, Random-forest, and support vector machine) were applied to identify the key lncRNAs. A predictive model for oxaliplatin sensitivity and a prognostic model based on key lncRNAs were established. The published datasets, and cell experiments were used to verify the predictive value.

RESULTS

A total of 805 tumor cell lines from GDSC were divided into oxaliplatin sensitive (top 1/3) and resistant (bottom 1/3) groups based on their IC50 values, and 113 lncRNAs, which were differentially expressed between the two groups, were selected and incorporated into four machine learning algorithms, and seven key lncRNAs were identified. The predictive model exhibited good predictions for oxaliplatin sensitivity. The prognostic model exhibited high performance in patients with CRC who underwent oxaliplatin-based chemotherapies. Four lncRNAs, including C20orf197, UCA1, MIR17HG, and MIR22HG, displayed consistent responses to oxaliplatin treatment in the validation analysis.

CONCLUSION

Certain lncRNAs were associated with oxaliplatin sensitivity and predicted the response to oxaliplatin treatment. The prognostic models established based on the key lncRNAs could predict the prognosis of patients given oxaliplatin-based chemotherapy.

Role of ferroptosis in colorectal cancer

Colorectal cancer (CRC) is the second deadliest cancer and the third-most common malignancy in the world. Surgery, chemotherapy, and targeted therapy have been widely used to treat CRC, but some patients still develop resistance to these treatments. Ferroptosis is a novel non-apoptotic form of cell death. It is an iron-dependent non-apoptotic cell death characterized by the accumulation of lipid reactive oxygen species and has been suggested to play a role in reversing resistance to anticancer drugs. This review summarizes recent advances in the prognostic role of ferroptosis in CRC and the mechanism of action in CRC.

Emerging roles of non-coding RNAs in colorectal cancer oxaliplatin resistance and liquid biopsy potential

Colorectal cancer (CRC) is one of the most common malignancies of the digestive tract, with the annual incidence and mortality increasing consistently. Oxaliplatin-based chemotherapy is a preferred therapeutic regimen for patients with advanced CRC. However, most patients will inevitably develop resistance to oxaliplatin. Many studies have reported that non-coding RNAs (ncRNAs), such as microRNAs, long non-coding RNAs, and circular RNAs, are extensively involved in cancer progression. Moreover, emerging evidence has revealed that ncRNAs mediate chemoresistance to oxaliplatin by transcriptional and post-transcriptional regulation, and by epigenetic modification. In this review, we summarize the mechanisms by which ncRNAs regulate the initiation and development of CRC chemoresistance to oxaliplatin. Furthermore, we investigate the clinical application of ncRNAs as promising biomarkers for liquid CRC biopsy. This review provides new insights into overcoming oxaliplatin resistance in CRC by targeting ncRNAs.

The role of lncRNA H19 in tumorigenesis and drug resistance of human Cancers

Systemic therapy is one of the most significant cancer treatments. However, drug resistance often appears and has become the primary cause of cancer therapy failure. Regulation of drug target, drug metabolism and drug efflux, cell death escape (apoptosis, autophagy, et al.), epigenetic changes, and many other variables are complicatedly involved in the mechanisms of drug resistance. In various types of cancers, long non-coding RNA H19 (lncRNA H19) has been shown to play critical roles in tumor development, proliferation, metastasis, and multiple drug resistance as well. The efficacy of chemotherapy, endocrine therapy, and targeted therapy are all influenced by the expression of H19, especially in breast cancer, liver cancer, lung cancer and colorectal cancer. Here, we summarize the relationship between lncRNA H19 and tumorigenesis, and illustrate the drug resistance mechanisms caused by lncRNA H19 as well. This review may provide more therapeutic potential targets for future cancer treatments.

Identification of Novel miRNAs, Targeting Genes, Signaling Pathway, and the Small Molecule for Overcoming Oxaliplatin Resistance of Metastatic Colorectal Cancer

One of the globally common cancers is colorectal cancer (CRC). At present, a surgical approach remains a good option for CRC patients; however, 20% of surgically treated CRC patients experience metastasis. Currently, even the first-line used drug, oxaliplatin, remains inadequate for treating metastatic CRC, and its side effect of neurotoxicity is a major problem when treating CRC. The Gene Omnibus GSE42387 database contains gene expression profiles of parental and oxaliplatin-resistant LoVo cell lines. Differentially expressed genes (DEGs) between parental and oxaliplatin-resistance LoVo cells, protein-protein interactions (PPIs), and a pathway analysis were determined to identify overall biological changes by an online DAVID bioinformatics analysis. The ability of DEGs to predict overall survival (OS) and disease-free survival (DFS) was validated by the SPSS 22.0, using liver metastasis CRC patient samples of GSE41258. The bioinformatics web tools of the GEPIA, the Human Protein Atlas, WebGestalt, and TIMER platforms were used. In total, 218 DEGs were identified, among which 105 were downregulated and 113 were upregulated. After mapping the PPI networks and pathways, 60 DEGs were identified as hub genes (with high degrees). Six genes (TGFB1, CD36, THBS1, FABP1, PCK1, and IRS1) were involved with malaria, PPAR signaling, and the adipocytokine signaling pathway. High expressions of CD36 and PCK1 were associated with the poor survival of CRC patients in the GSE41258 database. We predicted specific micro (mi)RNAs that targeted the 3′ untranslated region (UTR) of PCK1 by using miRWalk. It was found that three miRNAs, viz., miR-7-5p, miR-20a-3p, and miR-636, may be upstream targets of those genes. High expression levels of miR-7-5p, miR-20a-3p, and miR-636 were associated with poor OS of CRC patients, and the small-molecule compound, mersalyl, is a promising drug for treating oxaliplatin-resistant CRC. In conclusion, miR-7-5p miR-20a-3p, and miR-636 targeted the PCK1 biomarker in the PPAR signaling pathway, which is involved in oxaliplatin-resistant CRC. Meanwhile, mersalyl was identified as a potential drug for overcoming oxaliplatin resistance in CRC. Our findings may provide novel directions and strategies for CRC therapies.

Targeting Ferroptosis Pathway to Combat Therapy Resistance and Metastasis of Cancer

Ferroptosis is an iron-dependent regulated form of cell death caused by excessive lipid peroxidation. This form of cell death differed from known forms of cell death in morphological and biochemical features such as apoptosis, necrosis, and autophagy. Cancer cells require higher levels of iron to survive, which makes them highly susceptible to ferroptosis. Therefore, it was found to be closely related to the progression, treatment response, and metastasis of various cancer types. Numerous studies have found that the ferroptosis pathway is closely related to drug resistance and metastasis of cancer. Some cancer cells reduce their susceptibility to ferroptosis by downregulating the ferroptosis pathway, resulting in resistance to anticancer therapy. Induction of ferroptosis restores the sensitivity of drug-resistant cancer cells to standard treatments. Cancer cells that are resistant to conventional therapies or have a high propensity to metastasize might be particularly susceptible to ferroptosis. Some biological processes and cellular components, such as epithelial–mesenchymal transition (EMT) and noncoding RNAs, can influence cancer metastasis by regulating ferroptosis. Therefore, targeting ferroptosis may help suppress cancer metastasis. Those progresses revealed the importance of ferroptosis in cancer, In order to provide the detailed molecular mechanisms of ferroptosis in regulating therapy resistance and metastasis and strategies to overcome these barriers are not fully understood, we described the key molecular mechanisms of ferroptosis and its interaction with signaling pathways related to therapy resistance and metastasis. Furthermore, we summarized strategies for reversing resistance to targeted therapy, chemotherapy, radiotherapy, and immunotherapy and inhibiting cancer metastasis by modulating ferroptosis. Understanding the comprehensive regulatory mechanisms and signaling pathways of ferroptosis in cancer can provide new insights to enhance the efficacy of anticancer drugs, overcome drug resistance, and inhibit cancer metastasis.

Non-coding RNAs as emerging regulators and biomarkers in colorectal cancer

CRC is the third most common cancer occurring worldwide and the second leading cause of cancer deaths. In the year 2020, 1,931,590 new cases of CRC and 935,173 deaths were reported. The last two decades have witnessed an intensive study of noncoding RNAs and their implications in various pathological conditions including cancer. Noncoding RNAs such as miRNAs, tsRNAs, piRNAs, lncRNAs, pseudogenes, and circRNAs have emerged as promising prognostic and diagnostic biomarkers in preclinical studies of cancer. Some of these noncoding RNAs have also been shown as promising therapeutic targets for cancer treatment. In this review, we have discussed the emerging roles of various types of noncoding RNAs in CRC and their future implications in colorectal cancer management and research.

The Role of Exosomal Non-Coding RNAs in Colorectal Cancer Drug Resistance

Background: Colorectal cancer (CRC) is one of the most common types of cancer diagnosed worldwide with high morbidity; drug resistance is often responsible for treatment failure in CRC. Non-coding RNAs (ncRNAs) play distinct regulatory roles in tumorigenesis, cancer progression and chemoresistance. Methods: A literature search was conducted in PubMed database in order to sum up and discuss the role of exosomal ncRNAs (ex-ncRNAs) in CRC drug resistance/response and their possible mechanisms. Results: Thirty-six (36) original research articles were identified; these included exosome or extracellular vesicle (EV)-containing microRNAs (miRNAs), long non-coding RNAs (lncRNAs), circular RNAs (circRNAs) and small-interfering (siRNAs). No studies were found for piwi-interacting RNAs. Conclusions: Exosomal transfer of ncRNAs has been documented as a new mechanism of CRC drug resistance. Despite being in its infancy, it has emerged as a promising field for research in order to (i) discover novel biomarkers for therapy monitoring and/or (ii) reverse drug desensitization.

Suppressing the KIF20A/NUAK1/Nrf2/GPX4 signaling pathway induces ferroptosis and enhances the sensitivity of colorectal cancer to oxaliplatin

Oxaliplatin resistance can develop in colorectal cancer (CRC), which may involve inhibition of ferroptosis, although further research is needed to understand this potential mechanism. We evaluated CRC cells with acquired oxaliplatin resistance (HCT116-Or) or congenital resistance (H716) to determine whether a ferroptosis inducer (RSL3) or inhibitor (liproxstatin-1) could modulate the effects of oxaliplatin. The results suggested that induction of ferroptosis could significantly reverse the oxaliplatin resistance of the CRC cells. Bioinformatic and cytobiological searches also revealed that KIF20A was highly expressed in the oxaliplatin-resistant cell lines and was strongly correlated with survival among CRC patients. Silencing KIF20A enhanced cellular sensitivity to oxaliplatin both in vivo and in vitro, and silencing KIF20A also suppressed NUAK1 activation, while a NUAK1 agonist (ETC-1002) could reverse the oxaliplatin sensitivity of KIF20A-silenced cells. Moreover, silencing NUAK1 up-regulated the expression of PP1β, down-regulated the phosphorylation of downstream GSK3βSer9, suppressed the nuclear import of Nrf2, inhibited the expression of a ferroptosis key negative regulatory protein (GPX4), and blocked cellular resistance. Applying a Nrf2 agonist (oltipraz) also reversed the oxaliplatin sensitivity of NUAK1-silenced cells. Therefore, cellular ferroptosis may be inhibited via the KIF20A/NUAK1/PP1β/GPX4 pathway in CRC cells, which may underly the resistance of CRC to oxaliplatin.

The Emerging Landscape of Long Non-Coding RNAs in Colorectal Cancer Metastasis

Colorectal cancer (CRC) is one of the most common gastrointestinal cancers, with extremely high rates of morbidity and mortality. The main cause of death in CRC is distant metastasis; it affects patient prognosis and survival and is one of the key challenges in the treatment of CRC. Long non-coding RNAs (lncRNAs) are a group of non-coding RNA molecules with more than 200 nucleotides. Abnormal lncRNA expression is closely related to the occurrence and progression of several diseases, including cancer. Recent studies have shown that numerous lncRNAs play pivotal roles in the CRC metastasis, and reversing the expression of these lncRNAs through artificial means can reduce the malignant phenotype of metastatic CRC to some extent. This review summarizes the major mechanisms of lncRNAs in CRC metastasis and proposes lncRNAs as potential therapeutic targets for CRC and molecular markers for early diagnosis.

LncRNA MALAT1 Regulates the Progression and Cisplatin Resistance of Ovarian Cancer Cells via Modulating miR-1271-5p/E2F5 Axis

Background

Long non-coding RNAs (lncRNAs) and microRNAs (miRNAs) were reported to be related to the development of ovarian cancer (OC). In this study, the functional mechanisms of lncRNA metastasis associated with lung adenocarcinoma transcript 1 (MALAT1) and microRNA-1271-5p (miR-1271-5p) were explored in OC.

Methods

The level of MALAT1, miR-1271-5p, or E2F transcription factor 5 (E2F5) was detected by qRT-PCR. MTT assay, flow cytometry analysis and transwell migration and invasion assays were performed to determine cell proliferation, apoptosis, migration and invasion, respectively. E2F5 protein expression was detected by Western blot. The interaction between miR-1271-5p and MALAT1 or E2F transcription factor 5 (E2F5) was confirmed by the dual-luciferase reporter assay.

Results

MALAT1 and E2F5 level were increased, while miR-1271-5p level was decreased in cisplatin (DDP)-resistant OC tissues and cells. MALAT1 knockdown or miR-1271-5p upregulation decreased IC₅₀ of cisplatin, and inhibited cell proliferation, migration, invasion, and facilitated cell apoptosis in DDP-resistant OC cells. Moreover, MALAT1 sponged miR-1271-5p to upregulate E2F5 expression. Besides, MALAT1 knockdown decreased DDP resistance, inhibited cell proliferation, migration, invasion, and promoted cell apoptosis by sponging miR-1271-5p to downregulate E2F5 expression in DDP-resistant OC cell.

Conclusion

We demonstrated that MALAT1 mediated DDP-resistant OC development through miR-1271-5p/E2F5 axis, providing the theoretical basis for OC therapy.

The Liquid Biopsy in the Management of Colorectal Cancer: An Overview

Currently, there is a crucial need for novel diagnostic and prognostic biomarkers with high specificity and sensitivity in patients with colorectal cancer. A "liquid biopsy" is characterized by the isolation of cancer-derived components, such as circulating tumor cells, circulating tumor DNA, microRNAs, long non-coding RNAs, and proteins, from peripheral blood or other body fluids and their genomic or proteomic assessment. The liquid biopsy is a minimally invasive and repeatable technique that could play a significant role in screening and diagnosis, and predict relapse and metastasis, as well as monitoring minimal residual disease and chemotherapy resistance in colorectal cancer patients. However, there are still some practical issues that need to be addressed before liquid biopsy can be widely used in clinical practice. Potential challenges may include low amounts of circulating tumor cells and circulating tumor DNA in samples, lack of pre-analytical and analytical consensus, clinical validation, and regulatory endorsement. The aim of this review was to summarize the current knowledge of the role of liquid biopsy in the management of colorectal cancer.

lncRNA UCA1 Contributes to 5-Fluorouracil Resistance of Colorectal Cancer Cells Through miR-23b-3p/ZNF281 Axis

Purpose

The chemoresistance of 5-fluorouracil (5-FU) limited the application of chemotherapy in colorectal cancer (CRC) treatment. Herein, we aimed to uncover the potential mechanism behind the 5-FU resistance of CRC cells.

Methods

The abundance of long noncoding RNA urothelial carcinoma associated 1 (lncRNA UCA1), microRNA-23b-3p (miR-23b-3p) and zinc finger protein 281 (ZNF281) was measured by quantitative real-time polymerase chain reaction (qRT-PCR) in CRC tissues and cells. Western blot was conducted to examine autophagy-related proteins, apoptosis-associated proteins and ZNF281 in CRC tissues and cells. Cell counting kit-8 (CCK8) assay was performed to detect the viability and inhibitory concentration 50% (IC50) value of 5-FU of CRC cells. The apoptosis of CRC cells was measured by flow cytometry. The binding sites between miR-23b-3p and UCA1 or ZNF281 were predicted by miRcode and Starbase software, respectively, and the combination was confirmed by dual-luciferase reporter assay and RIP assay. Murine xenograft model was established to verify the role of UCA1 on the 5-FU resistance of CRC in vivo.

Results

The 5-FU resistance of CRC was positively related to the level of UCA1 and autophagy. UCA1 accelerated the 5-FU resistance of CRC cells through facilitating autophagy and suppressing apoptosis. MiR-23b-3p was a target of UCA1 in 293T and CRC cells. The knockdown of miR-23b-3p reversed the inhibitory effects of UCA1 interference on the 5-FU resistance and autophagy and the promoting impact on the apoptosis of CRC cells. ZNF281 could bind to miR-23b-3p in 293T cells. MiR-23b-3p elevated the 5-FU sensitivity through down-regulating ZNF281 in CRC cells. UCA1 interference enhanced the 5-FU sensitivity of CRC through miR-23b-3p/ZNF281 axis in vivo.

Conclusion

UCA1 mediated 5-FU resistance of CRC cells through facilitating autophagy and inhibiting apoptosis via miR-23b-3p/ZNF281 axis in vivo and in vitro.

Exosomal Transfer of lncRNA H19 Promotes Erlotinib Resistance in Non-Small Cell Lung Cancer via miR-615-3p/ATG7 Axis

Background

Drug resistance restrains the effect of drug therapy in non-small cell lung cancer (NSCLC). However, the mechanism of the acquisition of drug resistance remains largely unknown. This study aims to investigate the effect of exosomal lncRNA H19 on erlotinib resistance in NSCLC and the underlying mechanism.

Methods

HCC827 and A549 cells were continuously grafted into erlotinib-containing culture medium to establish erlotinib-resistant cell lines. The expression of H19 and miR-615-3p was detected by qRT-PCR. The protein levels of MMP2, MMP9, CD9, CD63 and ATG7 were measured by Western blot. Cell viability and proliferation were determined by Cell Counting Kit-8 (CCK-8) and 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay, respectively. Migration and invasion were assessed by transwell assay. Xenograft tumor models were used to investigate the effect of H19 on erlotinib resistance in vivo. Online software and dual-luciferase reporter assay were used to predicate the downstream targets and confirm the targeted relationships.

Results

H19 was upregulated in erlotinib-resistant cells, and knockdown of H19 inhibited cell proliferation, migration and invasion in erlotinib-resistant cells. Extracellular H19 can be packaged into exosomes. Exosomes containing H19 induced erlotinib resistance of sensitive cells, while knockdown of H19 abolished this effect. miR-615-3p was a target of H19 and can bind to ATG7. Exosomal H19 affected erlotinib resistance of erlotinib-resistant NSCLC cells via targeting miR-615-3p to regulate ATG7 expression. In addition, the serum exosomal H19 was upregulated in patients with erlotinib resistance. Furthermore, downregulated H19 decreased the resistance of tumor cells to erlotinib in vivo.

Conclusion

Our study demonstrated that exosomal H19 facilitated erlotinib resistance in NSCLC via miR-615-3p/ATG7 axis, which might provide a potential target for the diagnosis and treatment of NSCLC.

LncRNA H19 gene rs2839698 polymorphism is associated with a decreased risk of colorectal cancer in a Chinese Han population: A case-control study

Background

Long non‐coding RNA (lncRNA) H19 is involved in the carcinogenesis, progression, and metastasis of colorectal cancer (CRC). Recently, a few studies explored the relationship between lncRNA H19 gene rs2839698 polymorphism and CRC risk, but with conflicting findings.

Materials and methods

A case‐control study with 315 CRC cases and 441 controls was designed in a Chinese population. Genotyping was performed using PCR‐RFLP.

Results

It was found rs2839698 polymorphism was associated with a decreased risk of CRC (AA vs GG: OR, 0.73; 95% CI, 0.54‐0.98; P = .037; A vs G: OR, 0.78; 95% CI, 0.63‐0.96; P = .021). Stratified analyses indicated this positive association was also significant in the non‐smokers (AA vs GG: OR, 0.49; 95% CI, 0.25‐0.93; P = .029), non‐drinkers, those aged ≥ 60 years, and overweight individuals (BMI ≥ 24). In addition, rs2839698 polymorphism was also related to the lymph node metastasis (AA vs GG: OR, 0.43; 95% CI, 0.21‐0.88; P = .019) and tumor size (AA vs GG: OR, 0.42; 95% CI, 0.20‐0.88; P = .020) for patients with CRC.

Conclusion

To sum up, the lncRNA H19 gene rs2839698 polymorphism decreases the risk of CRC in Chinese individuals, especially among the non‐smokers, non‐drinkers, individuals aged ≥ 60 years, and overweight individuals (BMI ≥ 24). Thus, the lncRNA H19 gene rs2839698 polymorphism might be an important biomarker and diagnostic marker for predicting the susceptibility to CRC in Chinese Han population.

Expression and prognostic value of long non-coding RNA H19 in glioma via integrated bioinformatics analyses

Numerous discoveries have elucidated that long noncoding RNAs (lncRNAs) play a critical role in cancer malignant progression. However, their potential involvement in gliomas remains to be explored. Herein, the expression level of lncRNA H19 in glioma tissues, and its relevance with clinical characteristics were analyzed through Oncomine. The results showed that H19 was highly expressed in glioma tissues and its expression increased with the increase of malignancy. Next, GTEx and TCGA data were downloaded for differently expressed genes (DEGs) identification, Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses, and the correlation analyses between H19 expression and clinic features. Radiation therapy had a good effect on glioblastoma multiforme (GBM), but didn't have a good effect on low grade glioma (LGG). Meanwhile, the expression level of H19 could act as an indicator molecule indicating the effect of radiotherapy. Finally, gene set enrichment analysis (GSEA) and immune infiltration analysis were conducted. It was found that H19 could affect the immune infiltration level of glioma through copy number variations, thus affecting the prognosis of glioma patients. Collectively, H19 may be involved in the occurrence and development of glioma, and has potential reference value for the relief and immunotherapy of glioma.