二甲双胍抗肿瘤机制的研究进展

近年来,很多研究发现糖尿病能增加癌症的发生率和死亡率。目前,二甲双胍是临床治疗糖尿病的最常用药物之一。大量研究表明二甲双胍除具有降糖作用外,还有抑制肿瘤细胞生长的作用,因此可以降低2型糖尿病患者恶性肿瘤的发生率和死亡率。二甲双胍能激活腺苷活化蛋白激酶（AMPK）途径、阻滞细胞周期、调节胰岛素/IGF-1轴、调节肿瘤细胞的自噬效应、抑制肿瘤血管生成、激活体内免疫系统、增加化疗药物敏感性及杀伤肿瘤干细胞,从而杀灭肿瘤细胞,抑制肿瘤生长。二甲双胍具有安全、低毒的特性,将其应用于肿瘤的辅助治疗,可能会明显减轻化疗药物的毒副作用,提高患者的耐受性,并有望成为一种新型抗肿瘤药物。目前,二甲双胍的抗肿瘤机制仍处于实验及流行病学研究阶段,并未进入临床实验阶段,但其抗肿瘤作用是确切的。     

二甲双胍在恶性肿瘤放疗中的应用研究进展

二甲双胍(C4H11N5)是治疗2型糖尿病的主要药物.有研究显示,二甲双胍可以抑制肿瘤生长,改善恶性肿瘤患者的预后.近年越来越多的研究发现,二甲双胍可以改善肿瘤细胞的放疗敏感性.然而,二甲双胍增强恶性肿瘤放疗敏感性的具体机制尚未完全阐明.本研究将对有关二甲双胍联合放疗应用的最新发现进行综述,并着重介绍其在不同肿瘤中的疗...     

二甲双胍抗肿瘤机制研究进展

二甲双胍是目前Ⅱ型糖尿病的一线用药,主要通过抑制肝脏糖异生和胰岛素抵抗发挥降血糖作用。近年来随着对二甲双胍研究的深入,二甲双胍用于抗肿瘤治疗展现出了巨大的潜力。研究发现二甲双胍不仅能单独抑制肿瘤生长,能显著提升肿瘤放化疗和生物治疗等疗效。但目前关于二甲双胍发挥抗肿瘤作用的具体机制尚未达成共识。本文就近几年来二甲双胍在抗肿瘤领域的研究进展进行综述,主要从二甲双胍对肿瘤细胞的凋亡、自噬、上皮间质转化、肿瘤细胞代谢、联合用药等方面展开讨论,以期未来能够更深入和全面地理解二甲双胍的抗癌机制与临床应用范围,为临床肿瘤治疗提供新的思路。     

二甲双胍抗肿瘤作用机制的研究进展

二甲双胍作为Ⅱ型糖尿病患者的口服治疗药物已有50多年的历史。近年来多项研究发现并证实了二甲双胍在抗肿瘤方面的作用。研究发现二甲双胍能通过调控多种信号通路抑制肿瘤细胞的生长,为肿瘤治疗提供了新的思路。全文对近年来二甲双胍抗肿瘤的作用机制进行综述,希望能为肿瘤患者的治疗带来新的方向。     

二甲双胍抗肿瘤与 K－ras 突变的相关性

近年来,越来越多的研究表明,二甲双胍除了作为一种常用的降糖药物,还具有抗肿瘤作用。二甲双胍抗肿瘤作用机制包括：激活 AMPK 途径,促使细胞周期停滞,降低循环中胰岛素和 IGFs,自噬抗肿瘤,抑制肿瘤新生血管生成,杀灭肿瘤干细胞等。然而,二甲双胍抗肿瘤与基因突变是否相关还尚未明确。有研究证实,二甲双胍通过诱导细胞凋亡和抑制体内肿瘤细胞增殖的途径,能够有效地抑制 K －ras 突变型肿瘤细胞的生长,但并不抑制 K －ras 野生型肿瘤细胞的生长。因此,我们推论二甲双胍可作为 K －ras 突变型肿瘤的一个潜在的靶向药物。     

二甲双胍辅助治疗合并2型糖尿病的恶性肿瘤患者的专家共识（2022年版）

恶性肿瘤是近年来慢性非传染性疾病死亡的主要原因,也是影响人类预期寿命的最重要原因,其治疗效果差,预后不良。二甲双胍为2型糖尿病首选的降糖药物,其抗肿瘤的作用得到越来越多同行的认可。然而,目前国内外缺乏独立的临床指南、共识及大型前瞻性临床试验。本共识旨在为二甲双胍在抗肿瘤方面的临床应用提供参考。对于大多数合并2型糖尿病的恶性肿瘤患者,推荐联合使用二甲双胍治疗,可以辅助抗肿瘤及增强化疗药物敏感性,降低多种恶性肿瘤的发病率、转移率,从而降低死亡率;对于少部分合并2型糖尿病的恶性肿瘤患者,不推荐也不反对使用二甲双胍,如雌激素受体（estrogen receptor,ER）阴性或三阴性乳腺癌;对于大部分不合并糖尿病的恶性肿瘤患者,不推荐使用二甲双胍,如肺癌、结直肠癌、前列腺癌等;而对于极少部分不合并糖尿病的恶性肿瘤患者,在充分知情同意的情况下,可使用二甲双胍。     

二甲双胍抑制肿瘤细胞转移的研究进展

二甲双胍以其稳定的有效性、安全性及低廉的价格,已成为治疗2型糖尿病的首选用药。研究显示二甲双胍的应用可降低肿瘤的发病、复发及转移率,长期应用二甲双胍也可改善癌症患者预后,并延长寿命。二甲双胍的多重优势,促进其成为治疗和预防癌症的新兴选择。因此,深入研究二甲双胍抑制肿瘤细胞转移的机制对抗肿瘤治疗具有一定的指导意义。      

二甲双胍在乳腺癌中抗肿瘤作用研究进展

临床前研究表明降糖药二甲双胍对乳腺癌有抗肿瘤作用,能降低糖尿病患者乳腺癌发病风险和死亡风险,也能提高乳腺癌患者新辅助化疗后病理完全缓解率。体内外实验表明二甲双胍有效抑制各种乳腺癌细胞和移植瘤,并和化疗药物、HER2靶向药物、新型抗肿瘤药物有良好协同作用。主要分子机制包括全身性下调胰岛素及相关信号通路、肿瘤细胞内激活LKBl／AMPK、抑制下游mTOR通路等。目前各国开展了多个临床试验评估--sp双胍在乳腺癌防治中的应用价值。     

二甲双胍通过激活腺苷酸活化蛋白激酶(AMPK)的抗肿瘤机制

二甲双胍是一种传统的口服降糖药,临床上普遍用于2型糖尿病的治疗。近年来大量流行病学研究报道二甲双胍能够降低2型糖尿病患者的肿瘤发病率,亦有研究发现二甲双胍能在代谢途径、细胞周期、氧化应激、肿瘤干细胞转化等方面通过激活腺苷酸活化蛋白激酶(adenosin emonophosphate-activated protein kinase,AMPK)信号通路,从而抑制肿瘤细胞的生长、增殖以及转化。但二甲双胍通过激活AMPK的抗肿瘤机制仍存在着争议,其确切的作用机制有待进一步深入的研究,同时亟需大规模的临床试验来证实。     

二甲双胍对人肺腺癌A549细胞增殖和凋亡的调控

背景与目的:二甲双胍作为一种胰岛素增敏剂被用于Ⅱ型糖尿病的一线治疗。近来的临床研究发现二甲双胍可降低糖尿病患者的肿瘤发生率,提示它可能具有抗肿瘤的作用。本研究观察二甲双胍对人肺腺癌A549细胞增殖及凋亡的影响,并探讨其可能的机制。方法:二甲双胍干预人肺腺癌A549细胞48h后,采用MTT法检测其对细胞增殖的影响,流式细胞术检测细胞凋亡,实时PCR法检测p53、Bcl-2和Bax mRNA的转录情况。结果:经二甲双胍干预48h后,人肺腺癌A549细胞的增殖受到明显抑制,且该抑制作用呈药物浓度依赖性增加。当二甲双胍浓度为0.5、2和8mmol/L时对细胞生长的抑制率分别为(29±5)%、(68±3)%和(84.1±2.6)%。流式细胞术检测提示中、高浓度(2、8mmol/L)二甲双胍可促进A549细胞凋亡;其中,药物作用48h后,8mmol/L组细胞的早期凋亡率为(2.1±0.5)%,中、晚期凋亡率为(9±4)%,均显著高于对照组。二甲双胍干预后细胞凋亡相关基因p53、Bcl-2和BaxmRNA表达均上调,且Bcl-2/Bax比值下调。结论:二甲双胍能显著抑制人肺腺癌A549细胞增殖,促进细胞凋亡增加;其机制可能与上调细胞凋亡相关基因p53的表达及Bcl-2/Bax比值下降有关。     

Metformin: Taking away the candy for cancer?

Metformin is widely used in the treatment of diabetes mellitus type 2 where it reduces insulin resistance and diabetes-related morbidity and mortality. Population-based studies show that metformin treatment is associated with a dose-dependent reduction in cancer risk. The metformin treatment also increases complete pathological tumour response rates following neoadjuvant chemotherapy for breast cancer, suggesting a potential role as an anti-cancer drug. Diabetes mellitus type 2 is associated with insulin resistance, elevated insulin levels and an increased risk of cancer and cancer-related mortality. This increased risk may be explained by activation of the insulin- and insulin-like growth factor (IGF) signalling pathways and increased signalling through the oestrogen receptor. Reversal of these processes through reduction of insulin resistance by the oral anti-diabetic drug metformin is an attractive anti-cancer strategy. Metformin is an activator of AMP-activated protein kinase (AMPK) which inhibits protein synthesis and gluconeogenesis during cellular stress. The main downstream effect of AMPK activation is the inhibition of mammalian target of rapamycin (mTOR), a downstream effector of growth factor signalling. mTOR is frequently activated in malignant cells and is associated with resistance to anticancer drugs. Furthermore, metformin can induce cell cycle arrest and apoptosis and can reduce growth factor signalling. This review discusses the role of diabetes mellitus type 2 and insulin resistance in carcinogenesis, the preclinical rationale and potential mechanisms of metformin’s anti-cancer effect and the current and future clinical developments of metformin as a novel anti-cancer drug.     

Antidiabetic drug metformin induces apoptosis in human MCF breast cancer via targeting ERK signaling

Metformin is the most widely used antidiabetic drug for type II diabetes in the world. Recent studies provide clues that the use of metformin may be associated with reduced incidence and improved prognosis of certain cancers and there is increasing evidence of a potential efficacy of this agent as an anticancer drug. This observation led us to hypothesize that metformin might inhibit human breast cancer cells (MCF-7) growth. Here, we report that metformin induced apoptosis in human breast carcinoma cell lines MCF-7 cells via novel signaling pathway. Metformin induced apoptosis by arresting cells in G1 phase and reducing cyclin D level and increasing the expression of p21 and cyclin E. Molecular and cellular studies indicated that metformin significantly elevated p53 and Bax levels and reduced STAT3 and Bcl-2. Inhibitors of signaling proteins were used to study the mechanism(s) of metformin function. Receptor inhibitor studies indicated that p53 activation was mediated through insulin receptor (IR), not insulin-like growth factor-1 receptor (IGF-IR). Furthermore, MEK inhibitor significantly suppressed metformin-induced p53 and Bax elevation while ERK inhibitor generated a slight reduction in p53 levels. In contrast, PI3K inhibitor did not produce any effect on the metformin-elevated p53 levels. Finally, SAPK/JNK, known to be involved in apoptosis, was activated in cells treated with metformin and the activation appeared to occur downstream of ERK. All these results suggested that metformin activated p53, Bax, and induced tumor cell apoptosis through the ERK signaling pathway. This pathway has not been previously described for IR, p53, Bax activation, or apoptosis. Metformin, a novel inducer of apoptosis, and its analogs may offer a novel strategy for the treatment of cancer cells.     

Metformin inhibits mammalian target of rapamycin-dependent translation initiation in breast cancer cells

Metformin is used for the treatment of type 2 diabetes because of its ability to lower blood glucose. The effects of metformin are explained by the activation of AMP-activated protein kinase (AMPK), which regulates cellular energy metabolism. Recently, we showed that metformin inhibits the growth of breast cancer cells through the activation of AMPK. Here, we show that metformin inhibits translation initiation. In MCF-7 breast cancer cells, metformin treatment led to a 30% decrease in global protein synthesis. Metformin caused a dose-dependent specific decrease in cap-dependent translation, with a maximal inhibition of 40%. Polysome profile analysis showed an inhibition of translation initiation as metformin treatment of MCF-7 cells led to a shift of mRNAs from heavy to light polysomes and a concomitant increase in the amount of 80S ribosomes. The decrease in translation caused by metformin was associated with mammalian target of rapamycin (mTOR) inhibition, and a decrease in the phosphorylation of S6 kinase, ribosomal protein S6, and eIF4E-binding protein 1. The effects of metformin on translation were mediated by AMPK, as treatment of cells with the AMPK inhibitor compound C prevented the inhibition of translation. Furthermore, translation in MDA-MB-231 cells, which lack the AMPK kinase LKB1, and in tuberous sclerosis complex 2 null (TSC2(-/-)) mouse embryonic fibroblasts was unaffected by metformin, indicating that LKB1 and TSC2 are involved in the mechanism of action of metformin. These results show that metformin-mediated AMPK activation leads to inhibition of mTOR and a reduction in translation initiation, thus providing a possible mechanism of action of metformin in the inhibition of cancer cell growth.     

二甲双胍与肿瘤相关性的新观点与挑战

2型糖尿病（T2DM）是一种慢性疾病,在全球范围内迅速增长,它是各类癌症的重要风险因素。而二甲双胍是治疗T2DM最常用的处方药。通过流行病学和临床研究表明,使用二甲双胍可以降低T2DM患者的癌症风险,改善癌症患者的预后和生存率。此外,二甲双胍在癌症治疗中的临床试验正在扩大到非糖尿病人群。越来越多的研究者认为二甲双胍将会成为癌症预防和治疗的一个有吸引力的候选药物。在这里,我们总结了近年来二甲双胍在肿瘤预防与治疗中的流行病学证据与相关研究进展、二甲双胍的抗肿瘤机制,并探讨了提高二甲双胍对肿瘤的敏感性和预防肿瘤转移的可能性。     

Dietary energy availability affects primary and metastatic breast cancer and metformin efficacy

Dietary energy restriction has been shown to repress both mammary tumorigenesis and aggressive mammary tumor growth in animal studies. Metformin, a caloric restriction mimetic, has a long history of safe use as an insulin sensitizer in diabetics and has been shown to reduce cancer incidence and cancer-related mortality in humans. To determine the potential impact of dietary energy availability and metformin therapy on aggressive breast tumor growth and metastasis, an orthotopic syngeneic model using triple negative 66cl4 tumor cells in Balb/c mice was employed. The effect of dietary restriction, a standard maintenance diet or a diet with high levels of free sugar, were tested for their effects on tumor growth and secondary metastases to the lung. Metformin therapy with the various diets indicated that metformin can be highly effective at suppressing systemic metabolic biomarkers such as IGF-1, insulin and glucose, especially in the high energy diet treated animals. Long-term metformin treatment demonstrated moderate yet significant effects on primary tumor growth, most significantly in conjunction with the high energy diet. When compared to the control diet, the high energy diet promoted tumor growth, expression of the inflammatory adipokines leptin and resistin, induced lung priming by bone marrow-derived myeloid cells and promoted metastatic potential. Metformin had no effect on adipokine expression or the development of lung metastases with the standard or the high energy diet. These data indicate that metformin may have tumor suppressing activity where a metabolic phenotype of high fuel intake, metabolic syndrome, and diabetes exist, but may have little or no effect on events controlling the metastatic niche driven by proinflammatory events.     

Metformin inhibits prostate cancer cell proliferation,migration, and tumor growth through upregulation of PEDF expression

Metformin has been reported to inhibit the growth of various types of cancers, including prostate cancer. Yet the mode of anti-cancer action of metformin and the underlying mechanisms remain not fully elucidated. We hypothesized that the antitumorigenic effects of metformin are mediated through upregulation of pigment epithelium-derived factor (PEDF) expression in prostate cancer cells. In this report, metformin treatment significantly inhibited the proliferation and colony formation of prostate cancer cells, in a dose- and time-dependent manner. Meanwhile, Metformin markedly suppressed migration and invasion and induced apoptosis of both LNCaP and PC3 cancer cells. Metformin also reduced PC3 tumor growth in BALB/c nude mice in vivo. Furthermore, metformin treatment was associated with higher PEDF expression in both prostate cancer cells and tumor tissue. Taken together, metformin inhibits prostate cancer cell proliferation, migration, invasion and tumor growth, and these activities are mediated by upregulation of PEDF expression. These findings provide a novel insight into the molecular functions of metformin as an anticancer agent.     

Diabetes,metformin and cancer risk in myotonic dystrophy type I

Myotonic dystrophy type I (DM1) is an autosomal dominant multisystem disorder characterized by myotonia and muscle weakness. Type 2 diabetes (T2D) and cancer have been shown to be part of the DM1 phenotype. Metformin, a well-established agent for the management of T2D, is thought to have cancer-preventive effects in the general population. In our study, we aimed to assess the association between T2D, metformin use and the risk of cancer in DM1 patients. We identified a cohort of 913 DM1 patients and an age-, sex- and clinic-matched cohort of 12,318 DM1-free controls from the UK Clinical Practice Research Datalink, a large primary care records database. We used Cox regression models to assess cancer risk in T2D patients who were metformin users or nonusers compared to patients without T2D. Separate analyses were conducted for DM1 patients and controls. T2D was more prevalent in DM1 than in controls (8% vs. 3%, p < 0.0001). DM1 patients with T2D, compared to those without T2D, were more likely to develop cancer (hazard ratio [HR] = 3.60, 95% confidence interval [CI] = 1.18–10.97; p = 0.02), but not if they were treated with metformin (HR = 0.43, 95% CI = 0.06–3.35; p = 0.42). Among controls, we observed no significant associations between T2D and cancer risk in either users or nonusers of Metformin (HR = 1.28, 95% CI = 0.91–1.79; p = 0.16 and HR = 1.13, 95% CI = 0.72–1.79; p = 0.59, respectively). These results show an association between T2D and cancer risk in DM1 patients and may provide new insights into the possible benefits of Metformin use in DM1.     

Chloride intracellular channel 1 regulates the antineoplastic effects of metformin in gallbladder cancer cells

Metformin is the most commonly used drug for type 2 diabetes and has potential benefit in treating and preventing cancer. Previous studies indicated that membrane proteins can affect the antineoplastic effects of metformin and may be crucial in the field of cancer research. However, the antineoplastic effects of metformin and its mechanism in gallbladder cancer (GBC) remain largely unknown. In this study, the effects of metformin on GBC cell proliferation and viability were evaluated using the Cell Counting Kit‐8 (CCK‐8) assay and an apoptosis assay. Western blotting was performed to investigate related signaling pathways. Of note, inhibition, knockdown and upregulation of the membrane protein Chloride intracellular channel 1 (CLIC1) can affect GBC resistance in the presence of metformin. Our data demonstrated that metformin apparently inhibits the proliferation and viability of GBC cells. Metformin promoted cell apoptosis and increased the number of early apoptotic cells. We found that metformin can exert growth‐suppressive effects on these cell lines via inhibition of p‐Akt activity and the Bcl‐2 family. Notably, either dysfunction or downregulation of CLIC1 can partially decrease the antineoplastic effects of metformin while upregulation of CLIC1 can increase drug sensitivity. Our findings provide experimental evidence for using metformin as an antitumor treatment for gallbladder carcinoma.