Long non-coding RNA CHRF promotes proliferation and mesenchymal transition (EMT) in prostate cancer cell line PC3 requiring up-regulating microRNA-10b

Updated review on analysis of long non-coding RNAs as emerging diagnostic and therapeutic targets in prostate cancers

Despite advancements, prostate cancers (PCa) pose a significant global health challenge due to delayed diagnosis and therapeutic resistance. This review delves into the complex landscape of prostate cancer, with a focus on long-noncoding RNAs (lncRNAs). Also explores the influence of aberrant lncRNAs expression in progressive PCa stages, impacting traits like proliferation, invasion, metastasis and therapeutic resistance. The study elucidates how lncRNAs modulate crucial molecular effectors, including transcription factors and microRNAs, affecting signaling pathways such as androgen receptor signaling. Besides, this manuscript sheds light on novel concepts and mechanisms driving PCa progression through lncRNAs, providing a critical analysis of their impact on the disease's diverse characteristics. Besides, it discusses the potential of lncRNAs as diagnostics and therapeutic targets in PCa. Collectively, this work highlights state of art mechanistic comprehension and rigorous scientific approaches to advance our understanding of PCa and depict innovations in this evolving field of research.

MAPKAPK5-AS1/miR-515-5p/CAB39 Axis Contributes to Non-small Cell Lung Cancer Cell Proliferation and Migration

Several studies have elucidated the pivotal function that long noncoding RNAs (lncRNAs) exerted on the initiation and development of various human carcinomas, encompassing non-small cell lung cancer (NSCLC). In spite of the fact that lncRNA MAPKAPK5 antisense RNA 1 (MAPKAPK5-AS1) has already been investigated by researchers and confirmed to play oncogenic roles in colorectal cancer, the underlying regulatory function of MAPKAPK5-AS1 in NSCLC cells still remain unclear. In our research, we found that MAPKAPK5-AS1 was expressed at high levels in NSCLC cells. Biological functional assays unclosed that downregulation of MAPKAPK5-AS1 repressed proliferative and migratory capacities whereas promoted apoptotic level in NSCLC cells. Molecular mechanism experiments confirmed that, in NSCLC cells, MAPKAPK5-AS1 combined with miR-515-5p and negatively modulated miR-515-5p expression level. Besides, calcium-binding protein 39 (CAB39) expression level was verified to be negatively modulated by miR-515-5p whereas positively modulated by MAPKAPK5-AS1 in NSCLC cells. Furthermore, rescued-function assays disclosed that inhibited miR-515-5p expression or overexpressed CAB39 could restore the suppressive influence of MAPKAPK5-AS1 silence on NSCLC progression. In summary, MAPKAPK5-AS1 upregulates CAB39 expression level to facilitate NSCLC progression by sequestering miR-515-5p, providing promising biomarkers for NSCLC treatment.

A thorough understanding of the role of lncRNA in prostate cancer pathogenesis; Current knowledge and future research directions

In the entire world, prostate cancer (PCa) is one of the most common and deadly cancers. Treatment failure is still common among patients, despite PCa diagnosis and treatment improvements. Inadequate early diagnostic markers and the emergence of resistance to conventional therapeutic approaches, particularly androgen-deprivation therapy, are the causes of this. Long non-coding RNAs (lncRNAs), as an essential group of regulatory molecules, have been reported to be dysregulated through prostate tumorigenesis and hold great promise as diagnostic targets. Besides, lncRNAs regulate the malignant features of PCa cells, such as proliferation, invasion, metastasis, and drug resistance. These multifunctional RNA molecules interact with other molecular effectors like miRNAs and transcription factors to modulate various signaling pathways, including AR signaling. This study aimed to compile new knowledge regarding the role of lncRNA through prostate tumorigenesis in terms of their effects on the various malignant characteristics of PCa cells; in light of these characteristics and the significant potential of lncRNAs as diagnostic and therapeutic targets for PCa. AVAILABILITY OF DATA AND MATERIALS: Not applicable.

Malignant function of nuclear factor-kappaB axis in prostate cancer: Molecular interactions and regulation by non-coding RNAs

Prostate carcinoma is a malignant situation that arises from genomic alterations in the prostate, leading to changes in tumorigenesis. The NF-κB pathway modulates various biological mechanisms, including inflammation and immune responses. Dysregulation of NF-κB promotes carcinogenesis, including increased proliferation, invasion, and therapy resistance. As an incurable disease globally, prostate cancer is a significant health concern, and research into genetic mutations and NF-κB function has the efficacy to facilitate the introduction of novel therapies. NF-κB upregulation is observed during prostate cancer progression, resulting in increased cell cycle progression and proliferation rates. Additionally, NF-κB endorses resistance to cell death and enhances the capacity for metastasis, particularly bone metastasis. Overexpression of NF-κB triggers chemoresistance and radio-resistance, and inhibition of NF-κB by anti-tumor compounds can reduce cancer progression. Interestingly, non-coding RNA transcripts can regulate NF-κB level and its nuclear transfer, offering a potential avenue for modulating prostate cancer progression.

Long noncoding RNA as a potential diagnostic tool for prostate cancer: a systematic review and meta-analysis

PURPOSE

To identify consistently expressed lncRNAs and suitable lncRNAs with high sensitivity and specificity from multiple independent studies as potential biomarkers for PCa diagnostics.

METHODS

We searched multiple electronic databases including PubMed, Web of Science, EMBASE, Cochrane Library, CNKI, CQVIP, Wanfang, and CBMdisc for studies published up to July 2022. The quality of the included studies was assessed by two independent reviewers based on the QUADAS-2 tool using Review Manager 5.3. A vote-counting method was used based on the ranking of potential molecular biomarkers. The top-ranked lncRNAs were further assessed for diagnostic value using Meta-disc version 1.4 software.

RESULTS

Among the 26 included studies, 2 circulating lncRNAs (PCA3 and MALAT-1) were reported 3 or more times in PCa patients versus non-PCa patients. In further analysis, the areas under the curve of the summary receiver operating characteristic curves for PCA3 and MALAT-1 distinguishing PCa patients were 0.775 and 0.771, respectively.

CONCLUSIONS

Based on the current evidence, PCA3 and MALAT-1 are reliable lncRNAs for the diagnosis of PCa.

Long Non-Coding RNA DUXAP8 Acts as an Oncogene in Sinonasal Squamous Cell Carcinoma Through miR-584-5p/FNDC3B Pathway

Sinonasal squamous cell carcinoma (SNSCC) is one of the least frequent carcinomas in the head and neck and accounts for 60% to 75% of sinonasal malignancies. The role of long non-coding RNAs (lncRNAs) in cancer development has drawn great attention over the years. The current study intended to assess the role and specific mechanism of lncRNA double homeobox A pseudogene 8 (DUXAP8) in SNSCC. Quantitative real-time PCR (qRT-PCR) analysis was implemented to assess the expression level of DUXAP8, microRNA-584-5p (miR-584-5p), and fibronectin type III domain containing 3B (FNDC3B). Proliferation assays included colony formation assay, Cell Counting Kit-8 (CCK-8) assay, and 5-ethynyl-2′-deoxyuridine (EdU) assay. Transwell assays were implemented to monitor cell migration and invasion. Cell apoptosis was evaluated via terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL) and JC-1 experiments. Mechanism experiments included RNA pull-down assay, RNA binding protein immunoprecipitation (RIP) assay, and luciferase reporter assay. DUXAP8 is overexpressed in SNSCC cells. Functionally, DUXAP8 silencing suppresses the malignant progression of SNSCC. Furthermore, DUXAP8 up-regulates the expression of FNDC3B via sponging miR-584-5p. Rescue experiments demonstrated that DUXAP8 mediates the progression of SNSCC via up-regulating FNDC3B expression. In conclusion, DUXAP8 acts as an oncogene in SNSCC, which may be a new molecular marker for SNSCC.

Molecular Landscape of LncRNAs in Prostate Cancer: A focus on pathways and therapeutic targets for intervention

Background

One of the most malignant tumors in men is prostate cancer that is still incurable due to its heterogenous and progressive natures. Genetic and epigenetic changes play significant roles in its development. The RNA molecules with more than 200 nucleotides in length are known as lncRNAs and these epigenetic factors do not encode protein. They regulate gene expression at transcriptional, post-transcriptional and epigenetic levels. LncRNAs play vital biological functions in cells and in pathological events, hence their expression undergoes dysregulation.

Aim of review

The role of epigenetic alterations in prostate cancer development are emphasized here. Therefore, lncRNAs were chosen for this purpose and their expression level and interaction with other signaling networks in prostate cancer progression were examined.

Key scientific concepts of review

The aberrant expression of lncRNAs in prostate cancer has been well-documented and progression rate of tumor cells are regulated via affecting STAT3, NF-κB, Wnt, PI3K/Akt and PTEN, among other molecular pathways. Furthermore, lncRNAs regulate radio-resistance and chemo-resistance features of prostate tumor cells. Overexpression of tumor-promoting lncRNAs such as HOXD-AS1 and CCAT1 can result in drug resistance. Besides, lncRNAs can induce immune evasion of prostate cancer via upregulating PD-1. Pharmacological compounds such as quercetin and curcumin have been applied for targeting lncRNAs. Furthermore, siRNA tool can reduce expression of lncRNAs thereby suppressing prostate cancer progression. Prognosis and diagnosis of prostate tumor at clinical course can be evaluated by lncRNAs. The expression level of exosomal lncRNAs such as lncRNA-p21 can be investigated in serum of prostate cancer patients as a reliable biomarker.

Long Non-Coding RNA DUXAP8 Acts as an Oncogene in Sinonasal Squamous Cell Carcinoma Through miR-584-5p/FNDC3B Pathway

Sinonasal squamous cell carcinoma (SNSCC) is one of the least frequent carcinomas in the head and neck and accounts for 60% to 75% of sinonasal malignancies. The role of long non-coding RNAs (lncRNAs) in cancer development has drawn great attention over the years. The current study intended to assess the role and specific mechanism of lncRNA double homeobox A pseudogene 8 (DUXAP8) in SNSCC. Quantitative real-time PCR (qRT-PCR) analysis was implemented to assess the expression level of DUXAP8, microRNA-584-5p (miR-584-5p), and fibronectin type III domain containing 3B (FNDC3B). Proliferation assays included colony formation assay, Cell Counting Kit-8 (CCK-8) assay, and 5-ethynyl-2'-deoxyuridine (EdU) assay. Transwell assays were implemented to monitor cell migration and invasion. Cell apoptosis was evaluated via terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL) and JC-1 experiments. Mechanism experiments included RNA pull-down assay, RNA binding protein immunoprecipitation (RIP) assay, and luciferase reporter assay. DUXAP8 is overexpressed in SNSCC cells. Functionally, DUXAP8 silencing suppresses the malignant progression of SNSCC. Furthermore, DUXAP8 up-regulates the expression of FNDC3B via sponging miR-584-5p. Rescue experiments demonstrated that DUXAP8 mediates the progression of SNSCC via up-regulating FNDC3B expression. In conclusion, DUXAP8 acts as an oncogene in SNSCC, which may be a new molecular marker for SNSCC.

Crosstalk between Long Non Coding RNAs, microRNAs and DNA Damage Repair in Prostate Cancer: New Therapeutic Opportunities?

Simple Summary

Non-coding RNAs are a type of genetic material that doesn’t make protein, but performs diverse regulatory functions. In prostate cancer, most treatments target proteins, and resistance to such therapies is common, leading to disease progression. Targeting non-coding RNAs may provide alterative treatment options and potentially overcome drug resistance. Major types of non-coding RNAs include tiny ‘microRNAs’ and much longer ‘long non-coding RNAs’. Scientific studies have shown that these form a major part of the human genome, and play key roles in altering gene activity and determining the fate of cells. Importantly, in cancer, their activity is altered. Recent evidence suggests that microRNAs and long non-coding RNAs play important roles in controlling response to DNA damage. In this review, we explore how different types of non-coding RNA interact to control cell DNA damage responses, and how this knowledge may be used to design better prostate cancer treatments and tests.

Abstract

It is increasingly appreciated that transcripts derived from non-coding parts of the human genome, such as long non-coding RNAs (lncRNAs) and microRNAs (miRNAs), are key regulators of biological processes both in normal physiology and disease. Their dysregulation during tumourigenesis has attracted significant interest in their exploitation as novel cancer therapeutics. Prostate cancer (PCa), as one of the most diagnosed malignancies and a leading cause of cancer-related death in men, continues to pose a major public health problem. In particular, survival of men with metastatic disease is very poor. Defects in DNA damage response (DDR) pathways culminate in genomic instability in PCa, which is associated with aggressive disease and poor patient outcome. Treatment options for metastatic PCa remain limited. Thus, researchers are increasingly targeting ncRNAs and DDR pathways to develop new biomarkers and therapeutics for PCa. Increasing evidence points to a widespread and biologically-relevant regulatory network of interactions between lncRNAs and miRNAs, with implications for major biological and pathological processes. This review summarises the current state of knowledge surrounding the roles of the lncRNA:miRNA interactions in PCa DDR, and their emerging potential as predictive and diagnostic biomarkers. We also discuss their therapeutic promise for the clinical management of PCa.

Non-Coding RNAs Set a New Phenotypic Frontier in Prostate Cancer Metastasis and Resistance

Prostate cancer (PCa) mortality remains a significant public health problem, as advanced disease has poor survivability due to the development of resistance in response to both standard and novel therapeutic interventions. Therapeutic resistance is a multifaceted problem involving the interplay of a number of biological mechanisms including genetic, signaling, and phenotypic alterations, compounded by the contributions of a tumor microenvironment that supports tumor growth, invasiveness, and metastasis. The androgen receptor (AR) is a primary regulator of prostate cell growth, response and maintenance, and the target of most standard PCa therapies designed to inhibit AR from interacting with androgens, its native ligands. As such, AR remains the main driver of therapeutic response in patients with metastatic castration-resistant prostate cancer (mCRPC). While androgen deprivation therapy (ADT), in combination with microtubule-targeting taxane chemotherapy, offers survival benefits in patients with mCRPC, therapeutic resistance invariably develops, leading to lethal disease. Understanding the mechanisms underlying resistance is critical to improving therapeutic outcomes and also to the development of biomarker signatures of predictive value. The interconversions between epithelial-to-mesenchymal transition (EMT) and mesenchymal-to-epithelial transition (MET) navigate the prostate tumor therapeutic response, and provide a novel targeting platform in overcoming therapeutic resistance. Both microRNA (miRNA)- and long non-coding RNA (lncRNA)-mediated mechanisms have been associated with epigenetic changes in prostate cancer. This review discusses the current evidence-based knowledge of the role of the phenotypic transitions and novel molecular determinants (non-coding RNAs) as contributors to the emergence of therapeutic resistance and metastasis and their integrated predictive value in prostate cancer progression to advanced disease.

Long non-coding RNA CASC19 facilitates non-small cell lung cancer cell proliferation and metastasis by targeting the miR-301b-3p/LDLR axis

BACKGROUND

Non-small cell lung cancer (NSCLC) is a lethal tumor resulting in a large number of cancer-related deaths globally. Long noncoding RNAs (lncRNAs) may modulate tumor initiation and metastasis. Although dysregulation of lncRNA cancer susceptibility 19 (CASC19) is validated in NSCLC, further exploration of the CASC19-regulated mechanism in NSCLC is still needed.

METHODS

CASC19 expression was examined in NSCLC cells by a quantitative reverse transcriptase-polymerase chain reaction. The specific role of CASC19 in NSCLC was analyzed by cell counting kit-8, EdU, Transwell and western blot assays. The interaction between miR-301b-3p and CASC19 or low-density lipoprotein receptor (LDLR) was confirmed by luciferase reporter and RNA immunoprecipitation assays.

RESULTS

CASC19 is markedly overexpressed in NSCLC. Its deficiency impairs cell proliferation, as well as metastasis in NSCLC. Molecular mechanism experiments indicated that CASC19 negatively modulates the expression of miR-301b-3p and miR-301b-3p can bind with CASC19 in NSCLC. In addition, miR-301b-3p binds to LDLR to impair its expression in NSCLC. Finally, rescue experiments showed that miR-301b-3p inhibition or LDLR overexpression counteracted the CASC19 knockdown-mediated function on cell proliferation and metastasis in NSCLC.

CONCLUSIONS

CASC19 facilitates NSCLC cell proliferation and metastasis by targeting the miR-301b-3p/LDLR axis, offering a possible strategy for lncRNA-targeted treatment in NSCLC.

Overexpression of LINC00852 promotes prostate cancer cell proliferation and metastasis

AIM

Long noncoding RNAs play a key role in the development and progression of various human cancers. Recently, LINC00852 has been reported to be associated with spinal metastasis lung adenocarcinoma. However, the role and potential mechanisms of LINC00852 in prostate cancer cells remain largely unknown.

METHODS

LINC00852 expression in prostate cancer cells was examined by quantitative real-time polymerase chain reaction. Western blotting was used to detect protein expressions in prostate cancer cells. Cell cycle was analyzed by flow cytometric analysis. Cell proliferation was measured by cck-8 assay. The migration and invasion capabilities were determined using transwell assays.

RESULTS

In this study, we found that LINC00852 was highly expressed in prostate cancer tissues based on the TCGA database. Overexpression of LINC00852 mediated by lentivirus significantly reinforced the proliferation and colony formation abilities of prostate cancer cell linePC3. The migration and invasion capabilities were also augmented by overexpression of LINC00852. Flow cytometric analysis revealed that LINC00852 overexpression resulted in a decrease of cells in G0/G1 phase. Moreover, overexpression of LINC00852 affected the expression of epithelial-mesenchymal transition-related proteins.

CONCLUSIONS

Our data collectively demonstrate that LINC00852 contributes to prostate cancer proliferation and metastasis, indicating that LINC00852is a new promising diagnostic and therapeutic target for treatment of prostate cancer.

Novel role of lncRNA CHRF in cisplatin resistance of ovarian cancer is mediated by miR-10b induced EMT and STAT3 signaling

Ovarian Cancer (OC) is a highly lethal gynecological cancer which often progresses through acquired resistance against the administered therapy. Cisplatin is a common therapeutic for the treatment of OC patients and therefore it is critical to understand the mechanisms of resistance against this drug. We studied a paired cell line consisting of parental and cisplatin resistant (CR) derivative ES2 OC cells, and found a number of dysregulated lncRNAs, with CHRF being the most significantly upregulated lncRNA in CR ES2 cells. The findings corroborated in human patient samples and CHRF was significantly elevated in OC patients with resistant disease. CHRF was also found to be elevated in patients with liver metastasis. miR-10b was found to be mechanistically involved in CHRF mediated cisplatin resistance. It induced resistance in not only ES2 but also OVCAR and SKOV3 OC cells. Induction of epithelial-to-mesenchymal-transition (EMT) and activation of STAT3 signaling were determined to be the mechanisms underlying the CHRF-miR-10b axis-mediated cisplatin resistance. Down-regulation of CHRF reversed EMT, STAT3 activation and the resulting cisplatin resistance, which could be attenuated by miR-10b. The results were also validated in an in vivo cisplatin resistance model wherein CR cells were associated with increased tumor burden, CHRF downregulation associated with decreased tumor burden and miR-10b again attenuated the CHRF downregulation effects. Our results support a novel role of lncRNA CHRF in cisplatin resistance of OC and establish CHRF-miR-10b signaling as a putative therapeutic target for sensitizing resistant OC cells.

Long non-coding RNA DBH-AS1 promotes cancer progression in diffuse large B-cell lymphoma by targeting FN1 via RNA-binding protein BUD13

Diffuse large B-cell lymphoma (DLBC) is a subtype of lymphoma with the worst prognosis. Existing treatment methods are not effective enough due to its high occurrence of metastasis. Therefore, identification of effective therapeutic targets is becoming increasingly important. In this research, long non-coding RNA dopamine β hydroxylase antisense RNA 1 (DBH-AS1) was found to be upregulated in DLBC tissues and cells. Knockdown of DBH-AS1 suppressed the proliferation, migration, and invasion of cancer cells. Afterwards, RNA-binding protein BUD13 homolog (BUD13) was found to be upregulated in cancer tissues and cells while binding to DBH-AS1. Fibronectin 1 (FN1) was the downstream messenger RNA (mRNA) of BUD13. FN1 was upregulated in DLBC and was positively correlated with DBH-AS1. Further rescue assays proved that DBH-AS1 mediated FN1 expression by recruiting BUD13. In the meantime, BUD13 stabilized FN1 mRNA to promote FN1 expression. In this way, DBH-AS1/BUD13/FN1 axis was confirmed. A set of rescue assays proved that DBH-AS1 regulated DLBC progression via BUD13 and FN1. The function and mechanism of DBH-AS1 were investigated for the first time in DLBC. DBH-AS1 might become a therapeutic target in lymphoma treatment in the future.

A comprehensive review of the role of long non-coding RNAs in organs with an endocrine function

Long non-coding RNAs (lncRNAs) are transcripts with sizes larger than 200 nucleotides and no/ small open reading frame that cannot produce functional proteins. The number of these transcripts surpasses the number of coding genes. LncRNAs regulate many aspects of cell functions such as proliferation, cell cycle transition and differentiation; so their dysregulation has pervasive effects on cell phenotype. Increasing numbers of these transcripts have been shown to participate in the pathogenesis of cancer. In the current review, we summarize recent findings regarding the role of lncRNAs in tumors originated from organs which have an endocrine function. We mostly focused on adrenal, pancreas and pituitary gland as prototypes of these organs. Moreover, we presented the obtained data of the role of lncRNAs in prostate, ovarian and testicular cancers. Recent data highly supports the role of lncRNAs in the pathogenesis of cancers originated from these organs. Moreover, certain genomic loci within lncRNAs have been shown to be associated with risk of these cancers. Diagnostic and prognostic role of some lncRNAs in these cancers have been evaluated recently. Taken together, lncRNAs are putative biomarkers for cancers originated from organs which have an endocrine function.

LncRNA LOXL1-AS1 regulates the tumorigenesis and development of lung adenocarcinoma through sponging miR-423-5p and targeting MYBL2

Lung adenocarcinoma (LUAD) is the most common form of malignant tumor and closely correlated with high risk of death worldwide. Accumulating researches have manifested that long noncoding RNAs (lncRNAs) are deeply involved in the progression of multiple cancers. LncRNA LOXL1 antisense RNA 1 (LOXL1‐AS1) was identified as an oncogene in several cancers, nonetheless, its biological effect and regulatory mechanism have not been explained in LUAD. Our present study suggested that LOXL1‐AS1 expression was considerably increased in LUAD tissues and cells. Moreover, LOXL1‐AS1 deficiency notably hampered cell proliferation and migration as well as dramatically facilitated cell apoptosis. Through molecular mechanism assays, LOXL1‐AS1 was identified as a cytoplasmic RNA and acted as a sponge of miR‐423‐5p. Furthermore, MYBL2 was targeted and negatively modified by miR‐423‐5p. Rescue experiments revealed that MYBL2 knockdown could counteract miR‐423‐5p repression‐mediated enhancement on the progression of LOXL1‐AS1 downregulated LUAD cells. More importantly, MYBL2 was discovered to interact with LOXL1‐AS1 promoter, indicating a positive feedback loop of LOXL1‐AS1/miR‐423‐5p/MYBL2 in LUAD. These findings manifested the carcinogenic role of LOXL1‐AS1 and LOXL1‐AS1/miR‐423‐5p/MYBL2 feedback loop in LUAD, which could be helpful to explore effective therapeutic strategy for LUAD patients.

Long non-coding RNA CHRF modulates the progression of cerebral ischemia/reperfusion injury via miR-126/SOX6 signaling pathway

Ischemic stroke remains as a major cause for disability and death in the world. Long non-coding RNA (lncRNA) cardiac hypertrophy-related factor (CHRF) has been suggested as a crucial modulator in cardiac injury and various human cancers. Nevertheless, its effects and mechanism on ischemic stroke remains unclear. In this study, we found that CHRF was significantly correlated with miR-126, and miR-126 expression was decreased in the ischemic core following ischemia, while CHRF expression was increased according to the in vivo and in vitro experiments. Additionally, miR-126 significantly reduced oxygen-glucose deprivation and reoxygenation (OGD/R)-triggered apoptosis using TUNEL and flow cytometry analysis. Moreover, CHRF played as a competing endogenous RNA (ceRNA) and competed with Sex-determining region Y box 6 (SOX6) to direct binding with miR-126, subsequently regulating ischemic neuronal death. CHRF knockdown in vivo markedly prevented ischemic damage and alleviated neurological dysfunctions. Thereby, these results revealed a new molecular mechanism of lncRNA CHRF through targeting miR-126/SOX6 signaling to modulate ischemic neuronal injury, providing solid evidence to develop promising therapeutic strategies against cerebral ischemic stroke.