A Water‐Soluble Antimony‐Rich Polyoxometalate with Broad‐Spectrum Antitumor Activities

Abstract

Herein, a giant Sb-rich polyoxometalate (POM) {Sb 21 Tb 7 W 56 } is reported, which contains the largest number of Sb atoms in a POM so far. The Sbrich POM has many interesting structural features and is a rare example of a soluble and water-stable giant POM. Biomedical studies indicate that the Sb-rich POM exhibits broad-spectrum antitumor activity against various cancer cell lines by reactivating the P53-dependent apoptotic processes and disrupting the mitochondrial membrane. In addition, this Sb-rich POM was capable of suppressing the growth and metastasis of a breast cancer in vivo. This work demonstrates that Sb-rich POMs are promising candidates for the development of new anticancer drugs.Cancer remains the most malignant disease worldwide with high morbidity and mortality. [1] Although the development of therapeutic modalities has never stopped, chemotherapy remains one of the most prevalent therapeutic regimens. To date, chemotherapeutics based on organic, inorganic and hybrid species have been developed. [2] However, chemotherapeutics cause severe adverse effects including multiple organ failures and myelosuppression. [3] Thus, the exploration of new anticancer drugs with higher potencies and lower systemic toxicities remains challenging and requires longterm research.Polyoxometalates (POMs) have shown promising applications in various fields due to their unique structural features and rich physical and chemical properties, e.g. oxorich surface, tunable acid-base and redox properties. [4,5] These intriguing features also endow POMs with versatile bioactivities in the combat against viruses, bacteria and tumors. [6] Antimony, one heavy pnictogen, has been medicinally used for over 100 years. [7] Due to the stereo activity of the lone electron-pair, Sb-complexes can target protein tyrosine phosphatases and increase the generation of reactive oxygen species, leading to the apoptosis of cancer cells. [8] Recently, the introduction of Sb ions into POMs creating Sb-containing POMs has attracted increasing attention, because such composite POMs synergize the advantages of POMs and Sb, and thus become promising antitumor agents. [9] For example, {Co 4 Sb 9 W 24 }, [10] {Na 0.7 M 5.3 Sb 2 W 18 } (M = Ni/Co), [11] and {SbW 8 O 30 } [12] are reported to exhibit excellent antitumor activities. However, it is noteworthy that the known antitumor Sb-containing POMs are small-tomedium nuclearity (< 50) POMs with only a few Sb atoms (� 9, Table S1), and the incorporated Sb atoms in those POMs usually serve as heteroatoms wrapped by W/Mo shells, [13] which might hinder the contact with cancer cells thus impairing the antitumor activities of Sb. So, it is of great scientific interest to investigate whether increasing the nuclearity number of Sb atoms in a POM would improve the bioactivity against cancers. However, such studies remain largely unexplored due to the lack of Sb-rich POMs.Here, a rare and giant (> 2 nm) soluble Sb-rich POM H 27 [Sb 15 Tb 7 W 3 O 29 (OH) 3 (DMF)(H 2 O) 6 (SbW 8 O 30 )(SbW 9 O 33 ) 5 ]• 30 H 2 O ...

Organophosphonic acid and cerium functionalized antimonotungstate with electrochemical promise in biosensing bacterial dissimilatory sulfite reductase gene sequence

“…[14][15][16] With the speedy development of phosphotungstates and arsenotungstates, antimonotungstates (ATs) have gradually attracted increasing interest, because antimony is in the same main group as phosphorus and arsenic. [17][18][19] Reviewing the research progress of ATs, it has been powerfully demonstrated that lacunary AT SBUs can be considered as multidentate ligands to integrate with extra W centers, leading to the generation of some large AT aggregates (e.g. [ 26À [ref.…”

“…S1f-o and Table S1, ESI †). 19,[33][34][35][36][37][38][39][40] However, the types of organic ligands used in the aforementioned OLLFATs are relatively limited and are mainly organic ligands with carboxyl, amidogen or hydroxyl groups. As a result, it is considerably essential to constantly search for new kinds of organic ligands to construct ground-breaking OLLFATs and further promote the development of OFCMs.…”

Structural Evolution and Properties of Praseodymium Antimony Oxochlorides Based on a Chain-like Tertiary Building Unit

“…Metal–oxo cluster-based crystalline compounds have attracted increasing attention for their intriguing structural characteristics and properties [ 9 , 10 , 11 , 12 , 13 , 14 , 15 ]. Various types of metal–oxo clusters with tunable composition, size, and symmetry, such as polyoxometalate cluster [ 16 , 17 , 18 ], 3d–4f oxide cluster [ 19 , 20 ], and lanthanide oxide cluster [ 21 , 22 ], have been developed as SBUs to construct cluster-based crystals with complex structures.…”

Oxalate-assisted assembly of two polyoxotantalate supramolecular frameworks with proton conduction properties

“…The chemistry of polyoxometalates (POMs) has attracted sustained research interest in the past three decades because of their fascinating structures and unique physicochemical properties for potential applications in the areas of catalysis, medicine, magnetism, and materials science. 1,2 Among the POM family, polyoxotungstates, polyoxomolybdates, and polyoxovanadates represent the most extensively studied three subclasses of POMs. 3,4 In addition, another POM subclass of polyoxoniobates has also achieved rapid development in recent years.…”