SHMT-IN-2 is a highly selective small-molecule inhibitor of serine hydroxymethyltransferases (SHMTs), exhibiting IC50 values of 13nM for SHMT1 and 66nM for SHMT2 [1]. SHMT plays a central role in one-carbon metabolism, catalyzing the conversion of serine to glycine and the production of 5,10-methylenetetrahydrofolate, a critical cofactor for purine and pyrimidine biosynthesis [2]. By inhibiting both SHMT1 and SHMT2, SHMT-IN-2 disrupts nucleotide synthesis and DNA replication in tumor cells, thereby suppressing their proliferation. Notably, SHMT-IN-2 has demonstrated antitumor activity against diffuse large B-cell lymphoma (DLBCL) [1].
In vitro, SHMT-IN-2 (10μM) significantly reduced the levels of [²H] formate, HDO, and [²H] glycine in the culture medium of patient-derived glioblastoma cell lines, A11 and S2 cells [3]. In sorafenib-resistant hepatocellular carcinoma (HCC) cells, combined treatment with SHMT-IN-2 (30μM) and sorafenib for 24 hours enhanced cellular sensitivity to sorafenib [4]. When fertilized embryos were exposed to SHMT-IN-2 (95μM-10mM) for 3.5 hours, approximately 50% were arrested at the pronuclear stage, failing to progress to the 2-cell stage. Furthermore, only 25% of treated embryos developed to the blastocyst stage, a significant reduction compared to control embryos. SHMT-IN-2 was also found to alter the catalytic activity of SHMT2 [5]. Treatment of 298 human cancer cell lines with SHMT-IN-2 (98nM-50μM) for 96 hours resulted in marked inhibition of cancer cell proliferation[1]. Additionally, SHMT-IN-2 demonstrated weak but measurable antibacterial activity: treatment of Enterococcus faecalis and Enterococcus faecium with SHMT-IN-2 (10-20μM) yielded an EC50 of 2.9×10-6M [6].
References:
[1] Ducker GS, Ghergurovich JM, Mainolfi N, Suri V, Jeong SK, Hsin-Jung Li S, Friedman A, Manfredi MG, Gitai Z, Kim H, Rabinowitz JD. Human SHMT inhibitors reveal defective glycine import as a targetable metabolic vulnerability of diffuse large B-cell lymphoma. Proc Natl Acad Sci U S A. 2017 Oct 24;114(43):11404-11409.
[2] Heil SG, Van der Put NM, Waas ET, den Heijer M, Trijbels FJ, Blom HJ. Is mutated serine hydroxymethyltransferase (SHMT) involved in the etiology of neural tube defects? Mol Genet Metab. 2001 Jun;73(2):164-72.
[3] Hesse F, Low J, Cao J, Bulat F, Kreis F, Wright AJ, Brindle KM. Deuterium MRI of serine metabolism in mouse models of glioblastoma. Magn Reson Med. 2024 Nov;92(5):1811-1821.
[4] Dong Y, Chen Y, Wang Y, Zhao X, Zi R, Hao J, Ding Q, Jiang H, Wang X, Lu F, Liang H, Wei Z, Li J. Cancer-associated fibroblasts derived fibronectin extra domain A promotes sorafenib resistance in hepatocellular carcinoma cells by activating SHMT1. Genes Dis. 2024 May 20;11(6):101330.
[5] Shi M, Huai Y, Deng T, Zhang C, Song J, Wang J, Zhang Y, Chen ZJ, Zhao H, Wu K, Liu B. SHMT2 is essential for mammalian preimplantation embryonic development through de novo biosynthesis of nucleotide metabolites. Mol Ther Nucleic Acids. 2025 Mar 5;36(2):102499.
[6] Makino Y, Oe C, Iwama K, Suzuki S, Nishiyama A, Hasegawa K, Okuda H, Hirata K, Ueno M, Kawaji K, Sasano M, Usui E, Hosaka T, Yabuki Y, Shirouzu M, Katsumi M, Murayama K, Hayashi H, Kodama EN. Serine hydroxymethyltransferase as a potential target of antibacterial agents acting synergistically with one-carbon metabolism-related inhibitors. Commun Biol. 2022 Jun 23;5(1):619.
SHMT-IN-2 是一种靶向丝氨酸羟甲基转移酶（SHMT）蛋白的高选择性小分子抑制剂，对 SHMT1 和SHMT2的 IC50 分别为 13nM和66nM。 SHMT 是一碳代谢途径中的关键酶，催化丝氨酸向甘氨酸的转化，并生成 5,10-亚甲基四氢叶酸，这是一种在嘌呤和嘧啶合成中至关重要的辅因子。SHMT-IN-2 通过抑制 SHMT1 和 SHMT2 的活性，干扰肿瘤细胞的核苷酸合成和 DNA 复制，从而抑制其增殖。值得注意的是，SHMT-IN-2 已被证实对弥漫性大 B 细胞淋巴瘤（DLBCL）具有抗肿瘤活性。
在体外实验中，SHMT-IN-2（10μM）处理来源于患者的胶质母细胞瘤细胞系 A11 和 S2细胞，显著降低了细胞培养基中 [2H] 甲酸、HDO和[2H] 甘氨酸的含量。SHMT-IN-2 （30μM）与索拉非尼联合用药处理HCC索拉非尼耐药细胞24h后，增加了耐药细胞对索拉非尼的敏感性。用SHMT-IN-2（95μM-10mM）处理受精卵 3.5 h，导致约 50% 的胚胎在原核期停滞，未能进入二细胞期。此外，仅有 25% 的胚胎发育至囊胚期，显著低于对照组。研究还发现，SHMT-IN-2可改变SHMT2的催化活性。SHMT-IN-2（98nM-50μM）处理298种人类癌细胞96h后，显著抑制了癌细胞的增殖。 此外，SHMT-IN-2（10-20μM）对于细菌也有抑制作用，但抑制活性较弱，用SHMT-IN-2处理屎肠球菌和粪肠球菌时，其EC50为2.9×10–6 M。