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Cisplatin is one of the most common therapeutics used in treatments of several types of cancers. To enhance cisplatin lipophilicity and reduce resistance and side effects, a polyfluorinated bipyridine-modified cisplatin analogue, dichloro[4,4'-bis(2,2,3,3-tetrafluoropropoxy)methyl)-2,2'-bipryridine] platinum (TFBPC), was synthesized and therapeutic assessments were performed. TFBPC displayed superior effects in inhibiting the proliferation of several cisplatin-resistant human cancer cell lines, including MDA-MB-231 breast cancers, COLO205 colon cancers and SK-OV-3 ovarian cancers. TFBPC bound to DNA and formed DNA crosslinks that resulted in DNA degradation, triggering the cell death program through the PARP/Bax/Bcl-2 apoptosis and LC3-related autophagy pathway. Moreover, TFBPC significantly inhibited tumor growth in both animal models which include a cell line-derived xenograft model (CDX) of cisplatin-resistant MDA-MB-231, and a patient-derived xenograft (PDX) model of triple-negative breast cancers (TNBCs). Furthermore, the biopsy specimen from TFBPC-treated xenografts revealed decreased expressions of P53, Ki-67 and PD-L1 coupled with higher expression of cleaved caspase 3, suggesting TFBPC treatment was effective and resulted in good prognostic indications. No significant pathological changes were observed in hematological and biochemistry tests in blood and histological examinations from the specimen of major organs. Therefore, TFBPC is a potential candidate for treatments of patients suffering from TNBCs as well as other cisplatin-resistant cancers. [ABSTRACT FROM AUTHOR]

Fucoidan is a fucose-rich polysaccharide that has gained attention for its various anticancer properties. However, the effect and underlying mechanism of fucoidan on triple-negative breast cancer (TNBC) are still unknown. Herein, we investigated the anticancer potential of fucoidan from Laminaria japonica. We found that fucoidan showed modest antiproliferative activity against TNBC cells, while it effectively reduced migratory and invasive capacities. Mechanistically, fucoidan suppressed activation of MAPK and PI3K followed by inhibition of AP-1 and NF-κB signaling in TNBC. Additionally, fucoidan downregulated expressions of proangiogenic factors in TNBC cells, and fucoidan blocked tumor-elicited tube formation by human umbilical vascular endothelial cells (HUVECs). We also observed that fucoidan blocked tumor adhesion and invasion towards HUVECs. Surprisingly, fucoidan robustly suppressed tube formation on HUVECs. Moreover, fucoidan inhibited in vivo angiogenesis and micrometastasis in a transgenic zebrafish model. Together, L. japonica fucoidan exhibits potent antitumor effects by its attenuation of invasiveness and proangiogenesis in TNBC. • Fucoidan from Laminaria japonica exerts antitumor effects. • Fucoidan suppresses proangiogenesis and micrometastasis in TNBC. • Fucoidan blocks MAPK and PI3K signaling in TNBC. [ABSTRACT FROM AUTHOR]

Novel dual inhibitors of histone deacetylase (HDAC) and heat-shock protein 90 (HSP90) are synthesized and evaluated. These compounds are endowed with potent HDAC and HSP90 inhibitory activities with IC 50 values in nanomolar range with Compound 20 (HDAC IC 50 = 194 nM; HSP90α IC 50 = 153 nM) and compound 26 (HDAC IC 50 = 360 nM; HSP90α IC 50 = 77 nM) displaying most potent HDAC and HSP90α inhibitory activities. Both of these compounds induce HSP70 expression and down regulate HSP90 client proteins which play important roles in the regulation of survival and invasiveness in cancer cells. In addition, compounds 20 and 26 induce acetylation of α-tubulin and histone H3. Significantly, compounds 20 and 26 could effectively reduce programmed death-ligand 1 (PD-L1) expression in IFN-γ treated lung H1975 cells in a dose dependent manner. These findings suggest that dual inhibition of HDAC and HSP90 that can modulate immunosuppressive ability of tumor area may provide a better therapeutic strategy for cancer treatment in the future. Image 1 • N -alkyl-hydroxybenzoyl anilide hydroxamates show potent dual inhibition of HDAC and HSP90a. • Lead compounds 20 and 26 induce HSP70 expression and down regulate HSP90 client proteins. • Compounds 20 and 26 displayed their HDAC inhibitory effects due to increased acetylated α-tubulin and histone H3 levels. • Compounds 20 and 26 could effectively reduce programmed death-ligand 1 (PD-L1) expression in IFN-γ treated lung H1975 cells. [ABSTRACT FROM AUTHOR]

Microtubule-targeting agents (MTA) have enjoyed significant clinical success for decades. However, several mechanisms may cause inactivation of such drugs, leading to acquired resistance in patients treated with them. Therefore, drugs containing a stilbene-like skeleton and possessing dual inhibitory activity may provide a new and differentiated treatment for patients to overcome challenging acquired resistance. A new compound (16c) displays promising anticancer activity with GI 50 of 22 ± 2 and 12 ± 0.1 nM in vincristine-resistant nasopharyngeal (KB-Vin) cancer cells and etoposide-resistant nasopharyngeal (KB-7D) cancer cells and is better than vincristine, etoposide, ABT-751, and MS-275. A mechanistic study revealed that 16c interferes with the cell cycle distribution and induces cell cycle arrest at the G2/M phase and severe mitotic spindle defects followed by apoptosis. In addition, it produces much more significant cytotoxicity than vincristine and etoposide in the corresponding resistant cells, indicating that it may be a promising candidate to overcome drug resistance in cancer cells. Compound 16c also displays inhibitory activity against HDAC 1 and HDAC 2 with IC 50 values of 1.07 μM, and 1.47 μM, respectively. These findings may lead to a new type of structural motif for future development of drugs that could overcome acquired resistance to MTAs. Image 1 • N-phenyl-4-(2-phenylsulfonamido)-benzamides act as Microtubule-targeting agents. • 16c displays promising anticancer activity against resistant cancer cells. • 16c induces cell cycle arrest at the G2/M phase. • 16c significantly inhibits microtubule polymerization. • 16c exhibited inhibitory potential against HDAC 1, 2 and 3. [ABSTRACT FROM AUTHOR]

[Display omitted] • Synthesis of 32 tricyclic sulfamates as STS irreversible inhibitors. • SAR studies revealed that adjacent halogen-bearing phenyl gave the best inhibition. • 19 m , 19v , and 19w , had K I of 0.02 to 0.11 nM against STS. • Cellular potency is significant correlated with covalent kinetics (k inact/ K I). Steroid sulfatase inhibitors block the local production of estrogenic steroids and are attractive agents for the treatment of estrogen-dependent cancers. Inspiration of coumarin-based inhibitors, we synthesized thirty-two 5-oxa-1,2,3,4-tetrahydro-2H-chromeno-(3,4-c)pyridin-8-yl sulfamates , focusing on the substitution derivatives on the adjacent phenyl ring and evaluated their abilities to block STS from human placenta and MCF-7 cells. SAR analysis revealed that the incorporation of chlorine at either meta and/or para position of the adjacent phenyl ring of the tricyclic skeleton enhanced STS inhibition. Di-substitutions at the adjacent phenyl ring were superior to mono and tri-substitutions. Further kinetic analysis of these compounds revealed that chloride-bearing compounds, such as 19 m , 19v , and 19w , had K I of 0.02 to 0.11 nM and k inact / K I ratios of 8.8–17.5 nM-1min-1, a parameter indicated for the efficiency of irreversible inhibition. We also used the docking model to illustrate the difference in STS inhibitory potency of compounds. Finally, the safety and anti-cancer activity of selected compounds 19 m , 19v , and 19w were also studied, showing the results of low cytotoxicity on NHDF cell line and being more potent than irosustat on ZR-75–1 cell, which was a hormone-dependent cancer cell line with high STS expression. [ABSTRACT FROM AUTHOR]

A series of thiochromeno[2,3- c ]quinolin-12-one derivatives with various substitutions were synthesized and evaluated as topoisomerase (Topo) inhibitors. Six (8 , 10 , 12 , 14 , 19 , and 26) of 23 compounds showed strong inhibitory activities against Topo-mediated DNA relaxation and proliferation of five human cell lines including breast (MDA-MB-231, MDA-MB-468 and MCF7), colorectal (HCT116) and non-small cell lung (H1299) cancers. Among these, compounds 14 and 26 exhibited full inhibitory activities against Topo I at 3 μM and Topo IIα at 1 μM. Cancer cells treated with 26 accumulated DNA damage and were arrested at the G 2 /M phase. With time, cells proceeded to apoptosis, as revealed by increased amounts of cells with fragmented DNA and cleavage of caspase-8 and -9. In contrast, normal breast epithelial cells showed low sensitivity to 26. Taken together, our study identifies 26 as a potent Topo dual-inhibitor with low toxicity to normal cells, and elucidates that the terminal amino group of N -2-aminoethylamino or N -3-aminopropylamino at the 6th position and 8,10-di-halogen substituents on thiochromeno[2,3- c ]quinolin-12-one are critical for the Topo-inhibiting and cancer-killing activities. Image 1 • Six compounds identified as dual Topo inhibitors. • 26 exhibits the highest toxicity in five cancer cell lines but is less toxic in normal breast epithelial cells. • 26 traps Topo I and IIα on chromatin and suppresses their activities. • 26 triggers DNA damage, cell-cycle arrest at the G 2 /M phase, followed by apoptosis. [ABSTRACT FROM AUTHOR]