Department of Experimental Medicine and Biotechnology, Postgraduate Institute of Medical Education & Research (PGIMER), Chandigarh, 160012, India.
Department of Hepatology, Postgraduate Institute of Medical Education & Research (PGIMER), Chandigarh, 160012, India.
J Cancer Res Clin Oncol. 2023 Aug;149(9):5823-5839. doi: 10.1007/s00432-022-04544-7. Epub 2022 Dec 30.
The host dietary fibre is fermented into short-chain fatty acids (SCFA) by intestinal microbiota as bacterial metabolites like propionate, acetate and butyrate. Among these metabolites, the role of butyrate is well documented to provide energy to intestinal epithelial cells. Also, butyrate has anti-inflammatory and anti-tumour properties and decrease in its level by unbalanced diet can develops cancer. Lately, some research has suggested that sodium butyrate as an inhibitor of histone deacetylase (HDAC) may have anticancer potential for hepatocellular carcinoma (HCC), the most common type of liver cancer. Since, HCC is asymptomatic it is usually diagnosed at its advanced stage. Sorafenib with antiproliferative and antiangiogenic effects is the first line of treatment in advanced HCC. However, prolonged drug treatment to HCC patients develops adaptive resistance towards the sorafenib. Sorafenib resistance can also be enhanced by differentially expressed microRNAs. However, the significance of butyrate in HCC sorafenib resistance and its association with sorafenib-targeted microRNAs is yet to be unfurled. Here, an attempt has been made to explore the role of bacterial metabolite butyrate on sorafenib resistant HCC as well as on sorafenib-targeted microRNAs (miR-7641 and miR-199) to curtail sorafenib resistance in HCC.
Initially, in-silico analysis was performed using Human Metabolome Database (HMDB) so to identify specific butyrate producing faecal bacteria. Then, their specific 16s rRNA expression was compared between HCC patients and healthy individuals using qRT-PCR. Additionally, the cell viability (MTT) and apoptosis assays were performed in both parental and sorafenib resistant HepG2 cells to evaluate the role of sodium butyrate in sorafenib resistant HCC. Moreover, the association of sodium butyrate with sorafenib-targeted miR-7641 and miR-199 was also assessed using real time PCR, cell viability, cell apoptosis and transfection assays.
In silico analysis demonstrated Roseburia cecical, Roseburia intestinalis, Eubacterium rectal, Faecalibacterium prausnitzii as specific butyrate producing faecal bacteria and their 16s rRNA expression was downregulated in HCC patients. In vitro study revealed the presence of sodium butyrate also decreased the cell viability as well as enhanced cell apoptosis of both parental and resistant HepG2 cells. Interestingly, sodium butyrate also decreased the expression of both sorafenib-targeted miR-7641 and miR-199. Further, combination of both sodium butyrate and antimiR-7641 or antimiR-199 also increased apoptosis and decreased viability of resistant cells.
This is first study to unravel the association of butyrate producing bacteria with HCC patients and the significance of bacterial metabolite butyrate as anti-tumour in sorafenib resistant hepatocellular carcinoma. The study also demonstrated the plausible new aspects of bacterial metabolite butyrate association with sorafenib-targeted miRNAs (miR-7641 and miR-199). Hence, the study highlighted the therapeutic potential of bacterial metabolite butyrate that might improve the clinical management of hepatocellular carcinoma.
肠道微生物将宿主膳食纤维发酵成短链脂肪酸（SCFA），如丙酸、乙酸和丁酸等细菌代谢产物。在这些代谢产物中，丁酸为肠上皮细胞提供能量的作用已得到充分证实。此外，丁酸具有抗炎和抗肿瘤特性，饮食失衡导致其水平下降可能会引发癌症。最近，一些研究表明，作为组蛋白去乙酰化酶（HDAC）抑制剂的丁酸钠可能对肝癌（HCC）具有抗癌潜力，HCC 是最常见的肝癌类型。由于 HCC 没有症状，通常在晚期才被诊断出来。具有抗增殖和抗血管生成作用的索拉非尼是晚期 HCC 的一线治疗药物。然而，长期对 HCC 患者进行药物治疗会导致对索拉非尼产生适应性耐药。差异表达的 microRNAs 也会增强索拉非尼耐药性。然而，丁酸在 HCC 索拉非尼耐药性及其与索拉非尼靶向 microRNAs 之间的关联仍有待阐明。在这里，我们试图探讨细菌代谢物丁酸在索拉非尼耐药性 HCC 中的作用，以及丁酸在索拉非尼靶向 microRNAs（miR-7641 和 miR-199）中的作用，以减少 HCC 中的索拉非尼耐药性。
最初，我们使用人类代谢组数据库（HMDB）进行了计算机分析，以确定特定的丁酸产生粪便细菌。然后，使用 qRT-PCR 比较 HCC 患者和健康个体之间的特定 16s rRNA 表达。此外，我们还在亲本和索拉非尼耐药 HepG2 细胞中进行了细胞活力（MTT）和细胞凋亡测定，以评估钠丁酸钠在索拉非尼耐药 HCC 中的作用。此外，我们还使用实时 PCR、细胞活力、细胞凋亡和转染测定评估了钠丁酸钠与索拉非尼靶向 miR-7641 和 miR-199 的关联。
计算机分析表明，Roseburia cecical、Roseburia intestinalis、Eubacterium rectal 和 Faecalibacterium prausnitzii 是特定的丁酸产生粪便细菌，它们的 16s rRNA 表达在 HCC 患者中下调。体外研究表明，钠丁酸钠的存在也降低了亲本和耐药 HepG2 细胞的细胞活力并增强了细胞凋亡。有趣的是，钠丁酸钠还降低了两种索拉非尼靶向 miR-7641 和 miR-199 的表达。此外，钠丁酸钠和 antimiR-7641 或 antimiR-199 的联合使用也增加了耐药细胞的凋亡并降低了其活力。
这是第一项阐明丁酸产生细菌与 HCC 患者之间关联的研究，以及丁酸作为肿瘤抑制物在索拉非尼耐药性肝癌中的意义。该研究还证明了细菌代谢物丁酸与索拉非尼靶向 microRNAs（miR-7641 和 miR-199）之间存在新的关联。因此，该研究强调了细菌代谢物丁酸的治疗潜力，这可能会改善肝癌的临床管理。
