Knockdown of lncRNA ABHD11-AS1 Suppresses the Tumorigenesis of Pancreatic Cancer via Sponging miR-1231

Rhus coriaria induces autophagic and apoptotic cell death in pancreatic cancer cells

Background:Pancreatic cancer is a leading cause of cancer-related mortality worldwide with increasing global incidence. We previously reported the anticancer effect of Rhus coriaria ethanolic extract (RCE) in triple negative breast and colon cancer cells. Herein, we investigated the anticancer effect of RCE on human pancreatic cancer cells. Methods: Cell viability was measured using Cell Titer-Glo and staining of viable and dead cells based on differential permeability to two DNA binding dyes. Cell cycle distribution and annexin V staining was carried out in Muse cell analyzer. Protein level was determined by Western blot. Tumor growth was assessed by in ovo chick embryo chorioallantoic membrane assay. Results: We found that RCE significantly inhibited the viability and colony growth of pancreatic cancer cells (Panc-1, Mia-PaCa-2, S2-013, AsPC-1). The antiproliferative effects of RCE in pancreatic cancer cells (Panc-1 and Mia-PaCa-2) were mediated through induction of G1 cell cycle arrest, Beclin-1-independent autophagy, and apoptosis. RCE activated both the extrinsic and intrinsic pathways of apoptosis and regulated the Bax/Bcl-2 apoptotic switch. Mechanistically, we found that RCE inhibited the AKT/mTOR pathway, downstream of which, inactivation of the cell cycle regulator p70S6K and downregulation of the antiapoptotic protein survivin was observed. Additionally, we found that RCE-induced autophagy preceded apoptosis. Further, we confirmed the anticancer effect of RCE in a chick embryo xenograft model and found that RCE inhibited the growth of pancreatic cancer xenografts without affecting embryo survival. Conclusion: Collectively, our findings demonstrate that Rhus coriaria exerts potent anti-pancreatic cancer activity though cell cycle impairment, autophagy, and apoptosis, and is hence a promising source of anticancer phytochemicals.

The crosstalk between non-coding RNAs and cell-cycle events: A new frontier in cancer therapy

The cell cycle comprises sequential events during which a cell duplicates its genome and divides it into two daughter cells. This process is tightly regulated to ensure that the daughter cell receives identical copied chromosomal DNA and that any errors in the DNA during replication are correctly repaired. Cyclins and their enzyme partners, cyclin-dependent kinases (CDKs), are critical regulators of G- to M-phase transitions during the cell cycle. Mitogenic signals induce the formation of the cyclin/CDK complexes, resulting in phosphorylation and activation of the CDKs. Once activated, cyclin/CDK complexes phosphorylate specific substrates that drive the cell cycle forward. The sequential activation and inactivation of cyclin-CDK complexes are tightly controlled by activating and inactivating phosphorylation events induced by cell-cycle proteins. The non-coding RNAs (ncRNAs), which do not code for proteins, regulate cell-cycle proteins at the transcriptional and translational levels, thereby controlling their expression at different cell-cycle phases. Deregulation of ncRNAs can cause abnormal expression patterns of cell-cycle-regulating proteins, resulting in abnormalities in cell-cycle regulation and cancer development. This review explores how ncRNA dysregulation can disrupt cell division balance and discusses potential therapeutic approaches targeting these ncRNAs to control cell-cycle events in cancer treatment.

METTL3-deficiency Suppresses Neural Apoptosis to Induce Protective Effects in Cerebral I/R Injury via Inhibiting RNA m6A Modifications: A Pre-clinical and Pilot Study

N6-Methyladenosine (m6A) RNA methylation involves in regulating the initiation, progression and aggravation of cerebral ischemia-reperfusion (I/R) injury, however, the detailed functions and mechanisms by which m6A drives cerebral I/R injury are not fully understood. This study found that methyltransferase-like 3 (METTL3) m6A-dependently regulated cerebral I/R injury trough regulating a novel LncRNA ABHD11-AS1/miR-1301-3p/HIF1AN/HIF-1α axis. Specifically, the middle cerebral artery occlusion (MCAO)/reperfusion mice models and glucose deprivation (OGD)/reoxygenation (RX) astrocyte cell models were respectively established, and we verified that METTL3, ABHD11-AS1 and HIF1AN were upregulated, whereas miR-1301-3p and HIF-1α were downregulated in both MCAO/reperfusion mice tissues and OGD/RX astrocytes. Mechanical experiments confirmed that METTL3 m6A dependently increased stability and expression levels of ABHD11-AS1, and elevated ABHD11-AS1 sponged miR-1301-3p to upregulate HIF1AN, resulting in the downregulation of HIF-1α. Moreover, silencing of METTL3 rescued MCAO/reperfusion and OGD/RX-induced oxidative stress-associated cell apoptosis and cell cycle arrest in both mice brain tissues in vivo and the mouse primary astrocytes in vitro, which were abrogated by overexpressing ABHD11-AS1 and downregulating miR-1301-3p. Taken together, our study firstly reported a novel METTL3/m6A/ ABHD11-AS1/miR-1301-3p/HIF1AN/HIF-1α signaling cascade in regulating the progression of cerebral I/R injury, and future work will focus on investigating whether the above genes can be used as biomarkers for the treatment of cerebral I/R injury by performing clinical studies.

[Long non-coding RNA ABHD11-AS1 promotes glycolysis in gastric cancer cells to accelerate tumor progression]

OBJECTIVE

To explore the role of long non-coding RNA ABHD11-AS1 in regulation of glycolysis in gastric cancer cells and its molecular mechanism.

METHODS

The null plasmid pcDNA-Vector and the overexpression plasmid pcDNA-ABHD11-AS1 were transfected into human gastric cancer cell lines MKN45 and MGC803 with low ABHD11-AS1 expression, and the changes in cell proliferation, colony formation, migration and invasion were examined using CCK-8 assay, colony formation assay and Transwell assay. Glucose uptake and lactate production of the cells were detected to assess the changes in glycolytic activity. The LncMAP database was used to identify potential transcription factors regulated by ABHD11-AS1, and the candidate transcription factor was determined by literature review, and the result was verified using Western blotting.

RESULTS

Transfection with pcDNA-ABHD11-AS1 significantly increased ABHD11-AS1 expression in MGC803 and MKN45 cells, which exhibited obviously accelerated cell proliferation (P<0.05), increased colony formation rate and enhanced cell migration and invasion abilities (P<0.01). ABHD11-AS1 overexpression obviously promoted glycolysis in MGC803 and MKN45 cells (P<0.05). Analysis of the database suggested that ABHD11-AS1 may regulate the classical glycolysis-related gene c-Myc in gastric cancer cells. Western blotting demonstrated that the expression of c-Myc increased significantly after upregulating ABHD11-AS1 in gastric cancer cells.

CONCLUSION

ABHD11-AS1 promotes glycolysis in gastric cancer cells by upregulating c-Myc to accelerate gastric cancer progression.

Noncoding RNAs as regulators of STAT3 pathway in gastrointestinal cancers: Roles in cancer progression and therapeutic response

Gastrointestinal (GI) tumors (cancers of the esophagus, gastric, liver, pancreas, colon, and rectum) contribute to a large number of deaths worldwide. STAT3 is an oncogenic transcription factor that promotes the transcription of genes associated with proliferation, antiapoptosis, survival, and metastasis. STAT3 is overactivated in many human malignancies including GI tumors which accelerates tumor progression, metastasis, and drug resistance. Research in recent years demonstrated that noncoding RNAs (ncRNAs) play a major role in the regulation of many signaling pathways including the STAT3 pathway. The major types of endogenous ncRNAs that are being extensively studied in oncology are microRNAs, long noncoding RNAs, and circular RNAs. These ncRNAs can either be tumor-promoters or tumor-suppressors and each one of them imparts their activity via different mechanisms. The STAT3 pathway is also tightly modulated by ncRNAs. In this article, we have elaborated on the tumor-promoting role of STAT3 signaling in GI tumors. Subsequently, we have comprehensively discussed the oncogenic as well as tumor suppressor functions and mechanism of action of ncRNAs that are known to modulate STAT3 signaling in GI cancers.

Circulating Cell-Free Nucleic Acids as Biomarkers for Diagnosis and Prognosis of Pancreatic Cancer

A lack of reliable early diagnostic tools represents a major challenge in the management of pancreatic cancer (PCa), as the disease is often only identified after it reaches an advanced stage. This highlights the urgent need to identify biomarkers that can be used for the early detection, staging, treatment monitoring, and prognosis of PCa. A novel approach called liquid biopsy has emerged in recent years, which is a less- or non-invasive procedure since it focuses on plasmatic biomarkers such as DNA and RNA. In the blood of patients with cancer, circulating tumor cells (CTCs) and cell-free nucleic acids (cfNAs) have been identified such as DNA, mRNA, and non-coding RNA (miRNA and lncRNA). The presence of these molecules encouraged researchers to investigate their potential as biomarkers. In this article, we focused on circulating cfNAs as plasmatic biomarkers of PCa and analyzed their advantages compared to traditional biopsy methods.

Tumor mutation burden-related long non-coding RNAs is predictor for prognosis and immune response in pancreatic cancer

BACKGROUND

Pancreatic cancer is one of the most common malignant tumors with extremely poor prognosis. It is urgent to identify promising prognostic biomarkers for pancreatic cancer.

METHODS

A total of 266 patients with pancreatic adenocarcinoma (PAAD) in the Cancer Genome Atlas (TCGA)-PAAD cohort and the PACA-AU cohort were enrolled in this study. Firstly, prognostic tumor mutation burden (TMB)-related long non-coding RNAs (lncRNAs) were identified by DESeq2 and univariate analysis in the TCGA-PAAD cohort. And then, the TCGA-PAAD cohort was randomized into the training set and the testing set. Least absolute shrinkage and selection operator (LASSO) was used to construct the model in the training set. The testing set, the TCGA-PAAD cohort and the PACA-AU cohort was used as validation. The model was evaluated by multiple methods. Finally, functional analysis and immune status analysis were applied to explore the potential mechanism of our model.

RESULTS

A prognostic model based on fourteen TMB-related lncRNAs was established in PAAD. Patients with High risk score was associated with worse prognosis compared to those with low risk score in all four datasets. Besides, the model had great performance in the prediction of 5-year overall survival in four datasets. Multivariate analysis also indicated that the risk score based on our model was independent prognostic factor in PAAD. Additionally, our model had the best predictive efficiency in PAAD compared to typical features and other three published models. And then, our findings also showed that high risk score was also associated with high TMB, microsatellite instability (MSI) and homologous recombination deficiency (HRD) score. Finally, we indicated that high risk score was related to low immune score and less infiltration of immune cells in PAAD.

CONCLUSION

we established a 14 TMB-related lncRNAs prognostic model in PAAD and the model had excellent performance in the prediction of prognosis in PAAD. Our findings provided new strategy for risk stratification and new clues for precision treatment in PAAD.

Pancreatic Cancer Cell-Derived Exosomes Promote Lymphangiogenesis by Downregulating ABHD11-AS1 Expression

Research on pancreatic cancer microbiomes has attracted attention in recent years. The current view is that enriched microbial communities in pancreatic cancer tissues may affect pancreatic cancer metastasis, including lymph node (LN) metastasis. Similar to carriers of genetic information between cells, such as DNA, mRNA, protein, and non-coding RNA, exosomes are of great importance in early LN metastasis in tumors, including pancreatic cancer. Our previous study showed that the long non-coding RNA ABHD11-AS1 was highly expressed in tissues of patients with pancreatic cancer, and was correlated with patient survival time. However, the role of ABHD11-AS1 in pancreatic cancer LN metastasis has rarely been studied. Hence, in this paper we confirmed that exosomes derived from pancreatic cancer cells could promote lymphangiogenesis in vitro and in vivo, and that the mechanism was related to the downregulation of ABHD11-AS1 expression in lymphatic endothelial cells, and to the enhancement of their ability to proliferate, migrate, and form tubes. These findings preliminarily show a new mechanism by which pancreatic cancer cells regulate peripheral lymphangiogenesis, providing a new therapeutic strategy for inhibiting LN metastasis in pancreatic cancer.

Long noncoding RNAs (lncRNAs) in pancreatic cancer progression

Long noncoding RNAs (lncRNAs) are RNA molecules involved in gene regulation at transcriptional, post-transcriptional, and epigenetic levels. LncRNAs participate in regulating apoptosis and autophagy in pancreatic cancer (PCa) and can promote and/or decrease the proliferation rate of tumor cells. The metastasis of PCa cells is tightly regulated by lncRNAs and they can affect the mechanism of epithelial-mesenchymal transition (EMT) to modulate metastasis. The drug resistance of PCa cells, especially to gemcitabine, can be affected by lncRNAs. In addition, lncRNAs enriched in exosomes can be transferred among tumor cells to regulate their proliferation and metastasis. Antitumor compounds, such as curcumin and ginsenosides, can regulate lncRNA expression in PCa therapy. As we discuss here, the expression level of lncRNAs can be considered as both a diagnostic and prognostic tool in patients with PCa.

ABHD11-AS1: An Emerging Long Non-Coding RNA (lncRNA) with Clinical Significance in Human Malignancies

The aberrant expression of lncRNAs has been linked to the development and progression of different cancers. One such lncRNA is ABHD11 antisense RNA 1 (ABHD11-AS1), which has recently gained attention for its significant role in human malignancies. ABHD11-AS1 is highly expressed in gastric, lung, breast, colorectal, thyroid, pancreas, ovary, endometrium, cervix, and bladder cancers. Several reports highlighted the clinical significance of ABHD11-AS1 in prognosis, diagnosis, prediction of cancer progression stage, and treatment response. Significantly, the levels of ABHD11-AS1 in gastric juice had been exhibited as a clinical biomarker for the assessment of gastric cancer, while its serum levels have prognostic potential in thyroid cancers. The ABHD11-AS1 has been reported to exert oncogenic effects by sponging different microRNAs (miRNAs), altering signaling pathways such as PI3K/Akt, epigenetic mechanisms, and N6-methyladenosine (m⁶A) RNA modification. In contrast, the mouse homolog of AHD11-AS1 (Abhd11os) overexpression had exhibited neuroprotective effects against mutant huntingtin-induced toxicity. Considering the emerging research reports, the authors attempted in this first review on ABHD11-AS1 to summarize and highlight its oncogenic potential and clinical significance in different human cancers. Lastly, we underlined the necessity for future mechanistic studies to unravel the role of ABHD11-AS1 in tumor development, prognosis, progression, and targeted therapeutic approaches.

Long non-coding RNA ABHD11-AS1 facilitates the progression of cervical cancer by competitively binding to miR-330-5p and upregulating MARK2

Cervical cancer (CC) is among the most prevalent gynecological malignancies. Participation of long non-coding RNA (lncRNA) in modulating biological behaviors of CC cells has been confirmed. However, the function of lncRNA ABHD11 antisense RNA 1 (ABHD11-AS1) in CC is still unclear. RT-qPCR and Western blot were performed for measuring RNA and protein levels. Functional assays were done to evaluate ABHD11-AS1 influences on cell proliferation, apoptosis, invasion and migration. After the verification of ABHD11-AS1 distribution in CC cells, mechanism assays were conducted to study the interaction of relative RNAs. ABHD11-AS1 expression was abnormally high in CC cells. In vitro experiments showed ABHD11-AS1 downregulation restrained CC cell malignant phenotypes. In vivo experiments proved ABHD11-AS1 knockdown impeded tumor growth. Moreover, miR-330-5p was corroborated to bind with ABHD11-AS1 in CC cells and microtubule affinity regulating kinase 2 (MARK2) was confirmed to be targeted by miR-330-5p. MiR-330-5p inhibition or MARK2 overexpression could countervail the suppressive effect of ABHD11-AS1 knockdown on CC cell malignant behaviors. We found that ABHD11-AS1 facilitated CC tumorigenesis through competitively sequestering miR-330-5p to upregulate MARK2, indicating ABHD11-AS1 as a potential biomarker in CC.