Mir-488 alleviates chemoresistance and glycolysis of colorectal cancer by targeting PFKFB3

CRISPR/Cas9 Screening Highlights PFKFB3 Gene as a Major Contributor to 5-Fluorouracil Resistance in Esophageal Cancer

BACKGROUND

Esophageal cancer (EC) is the eighth most common cancer and the sixth most common cause of death worldwide. Esophageal squamous cell carcinoma (ESCC) comprises the majority of esophageal cancers globally, and 5-Fluorouraci (5-FU) is one of the commonly used chemotherapeutics for this type of cancer. Chemoresistance to drugs is a main obstacle in the successful treatment of this malignancy.

METHODS

In this study, we used the CRISPR/Cas9 screening method to determine the target gene related to 5-FU drug resistance in esophageal cancer.

RESULTS

Our research findings indicate that the loss of PFKFB3 can increase the resistance of different human esophageal squamous cell carcinoma cell lines to 5-FU through various pathways. Specifically, in KYSE-70 cells, loss of PFKFB3 can induce epithelial-mesenchymal transition (EMT) and prolong the S phase of the cell cycle, allowing cancer cells to evade the effects of 5-FU and develop resistance. In the KYSE-270 and KYSE-150 cell lines, loss of PFKFB3 can upregulate the expression of Slug and Mcl-1, indirectly regulate Chk1 and promote its autophosphorylation, which in turn inhibits apoptosis, thus counteracting the effects of 5-FU.

CONCLUSIONS

Our research not only enriches our understanding of the biological characteristics of different ESCC cell lines but also provides new clinical insights for future personalized treatments. Assessing the status of PFKFB3 can help predict resistance to 5-FU in ESCC patients with different genetic backgrounds, allowing for more precise treatment planning. This personalized approach has the potential to improve treatment efficacy, reduce unnecessary drug use and side effects, and ultimately improve patient survival rates and quality of life.

Targeting ncRNAs to overcome metabolic reprogramming‑mediated drug resistance in cancer (Review)

The emergence of resistance to antitumor drugs in cancer cells presents a notable obstacle in cancer therapy. Metabolic reprogramming is characterized by enhanced glycolysis, disrupted lipid metabolism, glutamine dependence and mitochondrial dysfunction. In addition to promoting tumor growth and metastasis, metabolic reprogramming mediates drug resistance through diverse molecular mechanisms, offering novel opportunities for therapeutic intervention. Non‑coding RNAs (ncRNAs), a diverse class of RNA molecules that lack protein‑coding function, represent a notable fraction of the human genome. Due to their distinct expression profiles and multifaceted roles in various cancers, ncRNAs have relevance in cancer pathophysiology. ncRNAs orchestrate metabolic abnormalities associated with drug resistance in cancer cells. The present review provides a comprehensive analysis of the mechanisms by which metabolic reprogramming drives drug resistance, with an emphasis on the regulatory roles of ncRNAs in glycolysis, lipid metabolism, mitochondrial dysfunction and glutamine metabolism. Furthermore, the present review aimed to discuss the potential of ncRNAs as biomarkers for predicting chemotherapy responses, as well as emerging strategies to target ncRNAs that modulate metabolism, particularly in the context of combination therapy with anti‑cancer drugs.

Investigating the role of MicroRNA-519d-3p in enhancing chemosensitivity of colorectal cancer cells to 5-Fluorouracil through PFKFB3 targeting

OBJECTIVE

In the fight against Colorectal Cancer (CRC), chemotherapy resistance is a major obstacle. Therefore, it is imperative to identify effective biomarker therapeutics. Despite microRNAs (miRs) playing a crucial role in drug resistance, the mechanisms comprising miR-519d-3p's role in CRC drug resistance have not been fully understood. Therefore, the present study aimed to investigate the biological function of miR-519d-3p in the chemosensitivity of CRC cells to 5-Fluorouracil (5-FU).

METHODS

CRC cells were treated with 5-FU and transfected. Cellular proliferation, invasion, and apoptosis were evaluated. The relationship between miR-519d-3p and 6-Phosphofructokinase-2/Frucose-2, 6-Biphosphatase-3 (PFKFB3) was analyzed, and their interaction in CRC was further investigated. In vivo tumor experiments were conducted to investigate the function of miR-519d-3p and 5-FU in CRC.

RESULTS

As determined, CRC cells overexpressing miR-519d-3p were more sensitive to 5-FU in vitro, as miR-519d-3p inhibits proliferation and invasion and stimulates apoptosis. miR-519d-3p directly targeted PFKFB3. In CRC cells, PFKFB3 overexpression rescued miR-519d-3p-induced 5-FU toxicity. In vivo results showed that mice co-treated with miR-519d-3p mimics and 5-FU showed higher antitumor activity.

CONCLUSION

Overall, it may be possible to improve 5-FU chemosensitivity of CRC cells by targeting miR-519d-3p and PFKFB3.

Exploring the Link Between Noncoding RNAs and Glycolysis in Colorectal Cancer

Glycolysis is implicated in the onset and progression of colorectal cancer (CRC) through its influence on the proliferation, invasiveness, chemoresistance and immune system evasion of neoplasm cells. Increasing evidence has shown that the abnormal expression of noncoding RNAs (ncRNAs), especially microRNAs (miRNAs), long noncoding RNAs (lncRNAs) and circular RNAs (circRNAs), in CRC is closely related to glycolysis. In this review, we present a synthesis of the latest research insights into the modulatory roles and distinct pathways of ncRNAs in the glycolytic process in CRC. This knowledge may pave the way for identifying novel therapeutic targets, as well as novel prognostic and diagnostic biomarkers for CRC.

Role of glucose metabolic reprogramming in colorectal cancer progression and drug resistance

Colorectal cancer (CRC), with the incidence and mortality rising on a yearly basis, greatly threatens people's health. It is considered an important hallmark of tumorigenesis that aberrant glucose metabolism in cancer cells, particularly the Warburg effect. In CRC, the Warburg effect predominantly influences cancer development and progression via its involvement in the glycolytic pathway regarding cell metabolism. The critical mechanisms underlying this process include key glycolytic enzymes, transport proteins, regulatory molecules, and signaling pathways. Furthermore, targeting the reprogrammed glucose metabolism in cancer cells can be potentially used for CRC treatment. However, the mechanisms driving CRC onset and progression, especially in relation to glucose metabolism reprogramming, are not fully understood and represent an emerging field of research. The review aims at providing new insights into the role that glucose metabolism reprogramming plays in the progression of CRC progression together with its resistance to treatment. Ultimately, these insights strive to diminish the risks of CRC metastasis and recurrence.

Transcriptional regulation and post-translational modifications in the glycolytic pathway for targeted cancer therapy

Cancer cells largely rely on aerobic glycolysis or the Warburg effect to generate essential biomolecules and energy for their rapid growth. The key modulators in glycolysis including glucose transporters and enzymes, e.g. hexokinase 2, enolase 1, pyruvate kinase M2, lactate dehydrogenase A, play indispensable roles in glucose uptake, glucose consumption, ATP generation, lactate production, etc. Transcriptional regulation and post-translational modifications (PTMs) of these critical modulators are important for signal transduction and metabolic reprogramming in the glycolytic pathway, which can provide energy advantages to cancer cell growth. In this review we recapitulate the recent advances in research on glycolytic modulators of cancer cells and analyze the strategies targeting these vital modulators including small-molecule inhibitors and microRNAs (miRNAs) for targeted cancer therapy. We focus on the regulation of the glycolytic pathway at the transcription level (e.g., hypoxia-inducible factor 1, c-MYC, p53, sine oculis homeobox homolog 1, N6-methyladenosine modification) and PTMs (including phosphorylation, methylation, acetylation, ubiquitination, etc.) of the key regulators in these processes. This review will provide a comprehensive understanding of the regulation of the key modulators in the glycolytic pathway and might shed light on the targeted cancer therapy at different molecular levels.

Synthesis and Regulation of miRNA, Its Role in Oncogenesis, and Its Association with Colorectal Cancer Progression, Diagnosis, and Prognosis

The dysfunction of several types of regulators, including miRNAs, has recently attracted scientific attention for their role in cancer-associated changes in gene expression. MiRNAs are small RNAs of ~22 nt in length that do not encode protein information but play an important role in post-transcriptional mRNA regulation. Studies have shown that miRNAs are involved in tumour progression, including cell proliferation, cell cycle, apoptosis, and tumour angiogenesis and invasion, and play a complex and important role in the regulation of tumourigenesis. The detection of selected miRNAs may help in the early detection of cancer cells, and monitoring changes in their expression profile may serve as a prognostic factor in the course of the disease or its treatment. MiRNAs may serve as diagnostic and prognostic biomarkers, as well as potential therapeutic targets for colorectal cancer. In recent years, there has been increasing evidence for an epigenetic interaction between DNA methylation and miRNA expression in tumours. This article provides an overview of selected miRNAs, which are more frequently expressed in colorectal cancer cells, suggesting an oncogenic nature.

MiR-488-3p facilitates wound healing through CYP1B1-mediated Wnt/β-catenin signaling pathway by targeting MeCP2

INTRODUCTION

Diabetic wounds are difficult to heal, but the pathogenesis is unknown. MicroRNAs (miRNAs) are thought to play important roles in wound healing. The effect of miR-488-3p in wound healing was studied in this article.

MATERIALS AND METHODS

The gene methylation was measured by methylation specific PCR (MSP) assay. A dual-luciferase reporter assay was adopted to analyze the interaction between miR-488-3p and MeCP2.

RESULTS

Cytochrome P450 1B1 (CYP1B1) is a monooxygenase belonging to the cytochrome P450 family that aids in wound healing. Our findings showed that the miR-488-3p and CYP1B1 expression levels were much lower in wound tissues of diabetics with skin defects, but the methyl-CpG-binding protein 2 (MeCP2) level was significantly higher than that in control skin tissues. MiR-488-3p overexpression increased cell proliferation and migration, as well as HUVEC angiogenesis, while inhibiting apoptosis, according to function experiments. In vitro, MeCP2 inhibited wound healing by acting as a target of miR-488-3p. We later discovered that MeCP2 inhibited CYP1B1 expression by enhancing its methylation state. In addition, CYP1B1 knockdown inhibited wound healing. Furthermore, MeCP2 overexpression abolished the promoting effect of miR-488-3p on wound healing. It also turned out that CYP1B1 promoted wound healing by activating the Wnt4/β-catenin pathway. Animal experiments also showed that miR-488-3p overexpression could accelerate wound healing in diabetic male SD rats.

CONCLUSIONS

MiR-488-3p is a potential therapeutic target for diabetic wound healing since it improved wound healing by activating the CYP1B1-mediated Wnt4/-catenin signaling cascade via MeCP2.

Biological landscape and nanostructural view in development and reversal of oxaliplatin resistance in colorectal cancer

The treatment of cancer patients has been mainly followed using chemotherapy and it is a gold standard in improving prognosis and survival rate of patients. Oxaliplatin (OXA) is a third-platinum anti-cancer agent that reduces DNA synthesis in cancer cells to interfere with their growth and cell cycle progression. In spite of promising results of using OXA in cancer chemotherapy, the process of drug resistance has made some challenges. OXA is commonly applied in treatment of colorectal cancer (CRC) as a malignancy of gastrointestinal tract and when CRC cells increase their proliferation and metastasis, they can obtain resistance to OXA chemotherapy. A number of molecular factors such as CHK2, SIRT1, c-Myc, LATS2 and FOXC1 have been considered as regulators of OXA response in CRC cells. The non-coding RNAs are able to function as master regulator of other molecular pathways in modulating OXA resistance. There is a close association between molecular mechanisms such as apoptosis, autophagy, glycolysis and EMT with OXA resistance, so that apoptosis inhibition, pro-survival autophagy induction and stimulation of EMT and glycolysis can induce OXA resistance in CRC cells. A number of anti-tumor compounds including astragaloside IV, resveratrol and nobiletin are able to enhance OXA sensitivity in CRC cells. Nanoparticles for increasing potential of OXA in CRC suppression and reversing OXA resistance have been employed in cancer chemotherapy. These subjects are covered in this review article to shed light on molecular factors resulting in OXA resistance.

The roles and molecular mechanisms of non-coding RNA in cancer metabolic reprogramming

One of the key features of cancer is energy metabolic reprogramming which is tightly related to cancer proliferation, invasion, metastasis, and chemotherapy resistance. NcRNAs are a class of RNAs having no protein-coding potential and mainly include microRNAs, lncRNAs and circRNAs. Accumulated evidence has suggested that ncRNAs play an essential role in regulating cancer metabolic reprogramming, and the altered metabolic networks mediated by ncRNAs primarily drive carcinogenesis by regulating the expression of metabolic enzymes and transporter proteins. Importantly, accumulated research has revealed that dysregulated ncRNAs mediate metabolic reprogramming contributing to the generation of therapeutic tolerance. Elucidating the molecular mechanism of ncRNAs in cancer metabolic reprogramming can provide promising metabolism-related therapeutic targets for treatment as well as overcome therapeutic tolerance. In conclusion, this review updates the latest molecular mechanisms of ncRNAs related to cancer metabolic reprogramming.

Oncogenic Alterations of Metabolism Associated with Resistance to Chemotherapy

Metabolic reprogramming in cancer cells is a strategy to meet high proliferation rates, invasion, and metastasis. Also, several researchers indicated that the cellular metabolism changed during the resistance to chemotherapy. Since glycolytic enzymes play a prominent role in these alterations, the ability to reduce resistance to chemotherapy drugs is promising for cancer patients. Oscillating gene expression of these enzymes was involved in the proliferation, invasion, and metastasis of cancer cells. This review discussed the roles of some glycolytic enzymes associated with cancer progression and resistance to chemotherapy in the various cancer types.

The Critical Function of microRNAs in Developing Resistance against 5- Fluorouracil in Cancer Cells

Although there have been significant advancements in cancer treatment, resistance and recurrence in patients make it one of the leading causes of death worldwide. 5-fluorouracil (5-FU), an antimetabolite agent, is widely used in treating a broad range of human malignancies. The cytotoxic effects of 5-FU are mediated by the inhibition of thymidylate synthase (TYMS/TS), resulting in the suppression of essential biosynthetic activity, as well as the misincorporation of its metabolites into RNA and DNA. Despite its huge benefits in cancer therapy, the application of 5-FU in the clinic is restricted due to the occurrence of drug resistance. MicroRNAs (miRNAs) are small, non-coding RNAs that act as negative regulators in many gene expression processes. Research has shown that changes in miRNA play a role in cancer progression and drug resistance. This review examines the role of miRNAs in 5-FU drug resistance in cancers.

MEX3A promotes angiogenesis in colorectal cancer via glycolysis

As a gastrointestinal malignancy, colorectal cancer (CRC) is a main cause of cancer-related deaths worldwide. Mex-3 RNA-binding family member A (MEX3A) is upregulated in multiple types of tumors and plays a critical role in tumor proliferation and metastasis. However, the function of MEX3A in CRC angiogenesis has not been fully understood. Hence, the aim of this study was to explore the role of MEX3A in CRC angiogenesis and investigate its underlying mechanisms. MEX3A expression in CRC was first investigated by bioinformatics means and then measured by qRT-PCR and Western blot. CCK-8 assay was employed to test cell viability. Angiogenesis assay was used to assess angiogenesis. The protein levels of VEGF, FGF and SDF-1 were evaluated using Western blot. The expression levels of MYC, HK2 and PGK1 were investigated by qRT-PCR. Extracellular acidification rate (ECAR) and oxygen consumption rate (OCR) were determined by Seahorse XP 96. The levels of pyruvate, lactate, citric acid and malate were measured by corresponding kits. Bioinformatics analysis demonstrated high MEX3A expression in CRC tissues and MEX3A enrichment in glycolysis and angiogenesis pathways. Cell assays showed high MEX3A expression in CRC cells and its promoting effects in CRC cell proliferation and glycolysis as well as angiogenesis. Rescue experiment confirmed that glycolysis inhibitor 2-DG could offset the promoting effects of MEX3A on the proliferation, angiogenesis and glycolysis of CRC cells. In conclusion, MEX3A could facilitate CRC angiogenesis by activating the glycolytic pathway, suggesting that MEX3A may be a novel therapeutic target for CRC.

Transcriptome analysis of the adenoma-carcinoma sequences identifies novel biomarkers associated with development of canine colorectal cancer

The concept of adenoma-to-cancer transformation in human colorectal cancer (CRC) is widely accepted. However, the relationship between transcriptome features and adenoma to carcinoma transformation in canines is not clear. We collected transcriptome data from 8 normal colon tissues, 4 adenoma tissues, and 15 cancer tissues. Differential analysis was unable to determine the dynamic changes of genes but revealed that PFKFB3 may play a key role in this process. Enrichment analysis explained metabolic dysregulation, immunosuppression, and typical cancer pathways in canine colorectal tumors. MFuzz generated specific dynamic expression patterns of five differentially expressed genes (DEGs). Weighted correlation network analysis showed that DEGs in cluster 3 were associated with malignant tissues, revealing the key role of inflammatory and immune pathways in canine CRC, and the S100A protein family was also found to be involved in the malignant transformation of canine colorectal tumors. By comparing strategies between humans and dogs, we found five novel markers that may be drivers of CRC. Among them, GTBP4 showed excellent diagnostic and prognostic ability. This study was the first systematic exploration of transformation in canine CRC, complemented the molecular characteristics of the development and progression of canine CRC, and provided new potential biomarkers and comparative oncologic evidence for biomarker studies in human colorectal cancer.

Rewiring of mitochondrial metabolism in therapy-resistant cancers: permanent and plastic adaptations

Deregulation of tumor cell metabolism is widely recognized as a "hallmark of cancer." Many of the selective pressures encountered by tumor cells, such as exposure to anticancer therapies, navigation of the metastatic cascade, and communication with the tumor microenvironment, can elicit further rewiring of tumor cell metabolism. Furthermore, phenotypic plasticity has been recently appreciated as an emerging "hallmark of cancer." Mitochondria are dynamic organelles and central hubs of metabolism whose roles in cancers have been a major focus of numerous studies. Importantly, therapeutic approaches targeting mitochondria are being developed. Interestingly, both plastic (i.e., reversible) and permanent (i.e., stable) metabolic adaptations have been observed following exposure to anticancer therapeutics. Understanding the plastic or permanent nature of these mechanisms is of crucial importance for devising the initiation, duration, and sequential nature of metabolism-targeting therapies. In this review, we compare permanent and plastic mitochondrial mechanisms driving therapy resistance. We also discuss experimental models of therapy-induced metabolic adaptation, therapeutic implications for targeting permanent and plastic metabolic states, and clinical implications of metabolic adaptations. While the plasticity of metabolic adaptations can make effective therapeutic treatment challenging, understanding the mechanisms behind these plastic phenotypes may lead to promising clinical interventions that will ultimately lead to better overall care for cancer patients.

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.

MicroRNA-488: A miRNA with diverse roles and clinical applications in cancer and other human diseases

MicroRNAs (miRNAs) are a class of small non-coding RNAs that post-transcriptionally regulate the expression of approximately 50 % of all protein-coding genes. They have been demonstrated to act as key regulators in various pathophysiological processes and play significant roles in a wide range of human diseases, particularly cancer. Current research highlights the aberrant expression of microRNA-488 (miR-488) in multiple human diseases and its critical involvement in disease initiation and progression. Moreover, the expression level of miR-488 has been linked to clinicopathological features and patient prognosis across different diseases. However, a comprehensive systematic review of miR-488 is lacking. Therefore, our study aims to consolidate the current knowledge surrounding miR-488, with a primary focus on its emerging biological functions, regulatory mechanisms, and potential clinical applications in human diseases. Through this review, we aim to establish a comprehensive understanding of the diverse roles of miR-488 in the development of various diseases.

Recent advances microRNAs and metabolic reprogramming in colorectal cancer research

Colorectal cancer (CRC) is a cancer with the highest incidence and mortality. Alteration of gene expression is the main pathophysiological mechanism of CRC, which results in disturbed signaling pathways and cellular metabolic processes. MicroRNAs are involved in almost all pathophysiological processes and are correlative with colorectal cancer metabolism, proliferation, and chemotherapy resistance. Metabolic reprogramming, an important feature of cancer, is strongly correlative with the development and prognosis of cancers, including colorectal cancer. MicroRNAs can target enzymes involved in metabolic processes, thus playing a regulatory role in tumor metabolism. The disorder of the signaling pathway is another characteristic of tumor, which induces the occurrence and proliferation of tumors, and is closely correlative with the prognosis and chemotherapy resistance of tumor patients. MicroRNAs can target the components of the signaling pathways to regulate their transduction. Understanding the function of microRNAs in the occurrence and proliferation of CRC provides novel insights into the optimal treatment strategies, prognosis, and development of diagnosis in CRC. This article reviews the relationship between CRC and microRNA expression and hopes to provide new options for the diagnosis and treatment of CRC.

MicroRNAs as Predictive Biomarkers in Patients with Colorectal Cancer Receiving Chemotherapy or Chemoradiotherapy: A Narrative Literature Review

Colorectal cancer (CRC) is one of the most common malignancies and is associated with high mortality rates worldwide. The underlying mechanism of tumorigenesis in CRC is complex, involving genetic, lifestyle-related, and environmental factors. Although radical resection with adjuvant FOLFOX (5-fluorouracil, leucovorin, and oxaliplatin) chemotherapy and neoadjuvant chemoradiotherapy have remained mainstays of treatment for patients with stage III CRC and locally advanced rectal cancer, respectively, the oncological outcomes of these treatments are often unsatisfactory. To improve patients' chances of survival, researchers are actively searching for new biomarkers to facilitate the development of more effective treatment strategies for CRC and metastatic CRC (mCRC). MicroRNAs (miRs), small, single-stranded, noncoding RNAs, can post-transcriptionally regulate mRNA translation and trigger mRNA degradation. Recent studies have documented aberrant miR levels in patients with CRC or mCRC, and some miRs are reportedly associated with chemoresistance or radioresistance in CRC. Herein, we present a narrative review of the literature on the roles of oncogenic miRs (oncomiRs) and tumor suppressor miRs (anti-oncomiRs), some of which can be used to predict the responses of patients with CRC to chemotherapy or chemoradiotherapy. Moreover, miRs may serve as potential therapeutic targets because their functions can be manipulated using synthetic antagonists and miR mimics.

The role of PFKFB3 in maintaining colorectal cancer cell proliferation and stemness

Since generally confronting with the hypoxic and stressful microenvironment, cancer cells alter their glucose metabolism pattern to glycolysis to sustain the continuous proliferation and vigorous biological activities. Bifunctional 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase (PFK-2/FBPase-2) isoform 3 (PFKFB3) functions as an effectively modulator of glycolysis and also participates in regulating angiogenesis, cell death and cell stemness. Meanwhile, PFKFB3 is highly expressed in a variety of cancer cells, and can be activated by several regulatory factors, such as hypoxia, inflammation and cellular signals. In colorectal cancer (CRC) cells, PFKFB3 not only has the property of high expression, but also probably relate to inflammation-cancer transformation. Recent studies indicate that PFKFB3 is involved in chemoradiotherapy resistance as well, such as breast cancer, endometrial cancer and CRC. Cancer stem cells (CSCs) are self-renewable cell types that contribute to oncogenesis, metastasis and relapse. Several studies indicate that CSCs utilize glycolysis to fulfill their energetic and biosynthetic demands in order to maintain rapid proliferation and adapt to the tumor microenvironment changes. In addition, elevated PFKFB3 has been reported to correlate with self-renewal and metastatic outgrowth in numerous kinds of CSCs. This review summarizes our current understanding of PFKFB3 roles in modulating cancer metabolism to maintain cell proliferation and stemness, and discusses its feasibility as a potential target for the discovery of antineoplastic agents, especially in CRC.

Emerging role of non-coding RNAs in glucose metabolic reprogramming and chemoresistance in colorectal cancer

Metabolic reprogramming plays a critical role in colorectal cancer (CRC). It contributes to CRC by shaping metabolic phenotypes and causing uncontrolled proliferation of CRC cells. Glucose metabolic reprogramming is common in carcinogenesis and cancer progression. Growing evidence has implicated the modifying effects of non-coding RNAs (ncRNAs) in glucose metabolic reprogramming and chemoresistance in CRC. In this review, we have summarized currently published studies investigating the role of ncRNAs in glucose metabolic alterations and chemoresistance in CRC. Elucidating the interplay between ncRNAs and glucose metabolic reprogramming provides insight into exploring novel biomarkers for the diagnosis and prognosis prediction of CRC.

Hyperglycemia induces miR-26-5p down-regulation to overexpress PFKFB3 and accelerate epithelial–mesenchymal transition in gastric cancer

Gastric cancer (GC) is one of the most deadly malignancies with high morbidity worldwide. Cancer cells exhibited higher level of glucose catabolism than normal cells to meet the needs for rapid growth. Emerging evidences indicated that hyperglycemia has positive effects on the progression of tumor. As a vital regulator of glycolysis, 6-phosphofructo-2-kinase/fructose-2,6-bisphosphatase 3 (PFKFB3) was confirmed to have a higher expression level in tumor tissue and correlated with the prognosis of GC patients. However, the role of PFKFB3 in GC patients with hyperglycemia remains unclear. The data from The Cancer Genome Atlas (TCGA) and Gene Expression Omnibus (GEO) were utilized to analyze the expression level of PFKFB3 and conducted survival analysis of GC patients. Western blot assay was used to detect gene expression at the protein level. Small interfering RNA (siRNA) transfection assay was conducted to down-regulate the expression of PFKFB3. Cell functional assays were carried out to reflect the ability of cell proliferation and migration. The results indicated that PFKFB3 was significantly upregulated and its overexpression was associated with poor prognosis of GC patients. Besides, hyperglycemia stimulated the higher expression of PFKFB3 along with the enhanced proliferation, migration and epithelial–mesenchymal transition (EMT) in GC cells. Knocking down of PFKFB3 effectively reversed the effects of high glucose concentration on GC malignant phenotype and the opposite results were gained when miR-26-5p was inhibited. Therefore, PFKFB3 down-regulated by miR-26-5p inhibited the malignant phenotype of GC with hyperglycemia.

The Regulatory Network of MicroRNA in the Metabolism of Colorectal Cancer

Colorectal cancer (CRC) is the third most common malignant tumor in the world. During the progression of CRC, the entire metabolic network undergoes reprogramming, including marked changes in the regulation of glucose, lipid and amino acid metabolism. Although microRNAs (miRNAs) account for only 1% of the entire human genome, they play an important role in almost all physiological and pathological processes in the body. MiRNAs can react directly with key enzymes in the metabolic processes. MiRNAs also interact with other ncRNAs, as a member of non-coding RNA (ncRNA), to form their own regulatory network in various oncogenic pathways of CRC metabolism. The progression of colorectal cancer is closely related to the intestinal flora, where miRNAs act as important mediators. Understanding how miRNAs act in the regulatory network of CRC metabolism is helpful to elucidate the characteristics of tumor occurrence, proliferation, metastasis and drug resistance. This review summarizes the role of miRNAs in the metabolism of CRC and how miRNAs interact with key enzymes, ncRNA and intestinal flora to further discuss how miRNAs affect CRC and realize some new strategies for the early diagnosis and treatment of CRC.

The Mechanism of Warburg Effect-Induced Chemoresistance in Cancer

Although chemotherapy can improve the overall survival and prognosis of cancer patients, chemoresistance remains an obstacle due to the diversity, heterogeneity, and adaptability to environmental alters in clinic. To determine more possibilities for cancer therapy, recent studies have begun to explore changes in the metabolism, especially glycolysis. The Warburg effect is a hallmark of cancer that refers to the preference of cancer cells to metabolize glucose anaerobically rather than aerobically, even under normoxia, which contributes to chemoresistance. However, the association between glycolysis and chemoresistance and molecular mechanisms of glycolysis-induced chemoresistance remains unclear. This review describes the mechanism of glycolysis-induced chemoresistance from the aspects of glycolysis process, signaling pathways, tumor microenvironment, and their interactions. The understanding of how glycolysis induces chemoresistance may provide new molecular targets and concepts for cancer therapy.

5-Fluorouracil: A Narrative Review on the Role of Regulatory Mechanisms in Driving Resistance to This Chemotherapeutic Agent

5-fluorouracil (5-FU) is among the mostly administrated chemotherapeutic agents for a wide variety of neoplasms. Non-coding RNAs have a central impact on the determination of the response of patients to 5-FU. These transcripts via modulation of cancer-related pathways, cell apoptosis, autophagy, epithelial-mesenchymal transition, and other aspects of cell behavior can affect cell response to 5-FU. Modulation of expression levels of microRNAs or long non-coding RNAs may be a suitable approach to sensitize tumor cells to 5-FU treatment via modulating multiple biological signaling pathways such as Hippo/YAP, Wnt/β-catenin, Hedgehog, NF-kB, and Notch cascades. Moreover, there is an increasing interest in targeting these transcripts in various kinds of cancers that are treated by 5-FU. In the present article, we provide a review of the function of non-coding transcripts in the modulation of response of neoplastic cells to 5-FU.

Mir-488 alleviates chemoresistance and glycolysis of colorectal cancer by targeting PFKFB3

BACKGROUND

Considering the boosting effect of glycolysis on tumor chemoresistance, this investigation aimed at exploring whether miR-488/PFKFB3 axis might reduce drug resistance of colorectal cancer (CRC) by affecting glycolysis, proliferation, migration, and invasion of CRC cells.

METHOD

Totally, 288 CRC patients were divided into metastasis/recurrence group (n = 107) and non-metastasis/recurrence group (n = 181) according to their prognosis about 1 year after the chemotherapy, and their 3-year overall survival was also tracked. Besides, miR-488 expression was determined in peripheral blood of CRC patients and also in CRC cell lines (ie, W620, HT-29, Lovo, and HCT116). The targeted relationship between miR-488 and PFKFB3 was predicted by Targetscan software and confirmed by dual-luciferase reporter gene assay. Moreover, glycolysis and drug tolerance of CRC cells lines were assessed.

RESULTS

MiR-488 expression was significantly decreased in metastatic/recurrent CRC patients than those without metastasis/recurrence (P < .05), and lowly expressed miR-488 was suggestive of unfavorable 3-year survival, large tumor size, poor differentiation, in-depth infiltration, and advanced Duke stage of CRC patients (P < .05). Besides, CRC cell lines transfected by miR-488 mimic demonstrated decreases in glucose uptake and lactate secretion, increases in oxaliplatin/5-Fu-sensistivity, as well as diminished capability of proliferating, invading, and migratory (P < .05), which were reversible by extra transfection of pcDNA3.1-PFKFB3 (ie, miR-488 mimic + pcDNA3.1-PFKFB3 group). Finally, the mRNA level of PFKFB3 was down-regulated by miR-488 mimic in CRC cell lines after being targeted by it (P < .05).

CONCLUSION

The miR-488/PFKFB3 axis might clinically refine chemotherapeutic efficacy of CRC, given its modifying glycolysis and metastasis of CRC cells.

Mir-488 alleviates chemoresistance and glycolysis of colorectal cancer by targeting PFKFB3

BACKGROUND

Considering the boosting effect of glycolysis on tumor chemoresistance, this investigation aimed at exploring whether miR-488/PFKFB3 axis might reduce drug resistance of colorectal cancer (CRC) by affecting glycolysis, proliferation, migration, and invasion of CRC cells.

METHOD

Totally, 288 CRC patients were divided into metastasis/recurrence group (n = 107) and non-metastasis/recurrence group (n = 181) according to their prognosis about 1 year after the chemotherapy, and their 3-year overall survival was also tracked. Besides, miR-488 expression was determined in peripheral blood of CRC patients and also in CRC cell lines (ie, W620, HT-29, Lovo, and HCT116). The targeted relationship between miR-488 and PFKFB3 was predicted by Targetscan software and confirmed by dual-luciferase reporter gene assay. Moreover, glycolysis and drug tolerance of CRC cells lines were assessed.

RESULTS

MiR-488 expression was significantly decreased in metastatic/recurrent CRC patients than those without metastasis/recurrence (P < .05), and lowly expressed miR-488 was suggestive of unfavorable 3-year survival, large tumor size, poor differentiation, in-depth infiltration, and advanced Duke stage of CRC patients (P < .05). Besides, CRC cell lines transfected by miR-488 mimic demonstrated decreases in glucose uptake and lactate secretion, increases in oxaliplatin/5-Fu-sensistivity, as well as diminished capability of proliferating, invading, and migratory (P < .05), which were reversible by extra transfection of pcDNA3.1-PFKFB3 (ie, miR-488 mimic + pcDNA3.1-PFKFB3 group). Finally, the mRNA level of PFKFB3 was down-regulated by miR-488 mimic in CRC cell lines after being targeted by it (P < .05).

CONCLUSION

The miR-488/PFKFB3 axis might clinically refine chemotherapeutic efficacy of CRC, given its modifying glycolysis and metastasis of CRC cells.