Potent Antiproliferative Activity Research Articles

Discovery of Cytotoxic Nitric Oxide-Releasing Piperlongumine Derivatives Targeting Wnt/β-Catenin in Colon Cancer Cells.

Piperlongumine (1) increases reactive oxygen species (ROS) levels and induces apoptosis in cancer cells through various pathways. Nitric oxide (NO) donors have demonstrated potent anticancer activities with exogenous NO being oxidized by ROS in the tumor microenvironment to form highly reactive N-oxides (RNOS). This amplifies oxidative stress cascade reactions, ultimately inducing cancer cell apoptosis. To exploit this synergy, a series of NO-releasing piperlongumine derivatives (2-5) were designed and synthesized. These compounds were expected to release NO in cancer cells, simultaneously generating piperlongumine derivative fragments to enhance the anticancer effects. Compound 6, structurally similar to compounds 2-5 but not releasing NO, served as a control. Among these derivatives, compound 5 exhibited the most potent antiproliferative activity against HCT-116 cells and efficiently released NO in this cell line. Further investigation revealed that compound 5 inhibited colon cancer cell proliferation by modulating β-catenin expression, which is a pivotal protein in the Wnt/β-catenin signaling pathway. These findings highlight compound 5 as a promising candidate for colon cancer treatment targeting the Wnt/β-catenin pathway.

Acetalax (Oxyphenisatin acetate, NSC 59687) and bisacodyl Cause Oncosis in Triple Negative Breast Cancer Cell lines by Poisoning Ion Exchange Membrane Protein TRPM4.

Triple negative breast cancer (TNBC) is clinically aggressive and relatively unresponsive to current therapies. The development of new anticancer agents is needed. Oxyphenisatin acetate (Acetalax), which had been used as laxative has recently been reported to have anticancer activity in murine models. Here we demonstrate that Acetalax and its diphenolic laxative structural analog bisacodyl (Dulcolax) exhibit potent antiproliferative activity in TNBC cell lines and cause oncosis, a non-apoptotic cell death characterized by cellular and nuclear swelling and cell membrane blebbing leading to mitochondrial dysfunction, ATP depletion and enhanced immune and inflammatory responses. Mechanistically, we provide evidence that TRPM4 (Transient Receptor Potential Melastatin Member 4) is poisoned by Acetalax and bisacodyl in MDA-MB468, BT549 and HS578T TNBC cells. MDA-MB231 and MDA-MB436 TNBC cells without endogenous TRPM4 expression as well as TRPM 4 knockout TNBC cells were found to be Acetalax- and bisacodyl resistant. Conversely, ectopic expression of TRPM4 sensitized MDA-MB231 and MDA-MB436 cells to Acetalax. TRPM4 was also lost in cells with acquired Acetalax resistance. Moreover, TRPM4 is rapidly degraded by the ubiquitin-proteasome system upon acute exposure to Acetalax and bisacodyl. Together, these results demonstrate that TRPM4 is a previously unknown target of Acetalax and bisacodyl and that TRPM4 expression in cancer cells is a predictor of Acetalax and bisacodyl efficacy and could be used for the clinical development of these drugs as anticancer agents.

Design and synthesis of 6,20-epoxy A-ring modified oridonin derivatives with antitumor activity through extrinsic and mitochondrial pathways

Oridonin is an antitumor ent-kaurane diterpenoid that medicinal chemists have been paying close attention to in recent years. Herein, a novel 6,20-epoxy A-ring modified oridonin derivative 2 was obtained by a 6-step synthesis. A series of 14-O derivatives of 2 (EpskA1-EpskA24) were synthesized to further enhance the activity. Based on their cytotoxicity against MCF-7, A549 and L-02 cells, EpskA9, EpskA10 and EpskA21 were chosen for further screening to obtain a wider antitumor spectrum. Collectively, EpskA21 showed the most potent antiproliferative activity, inhibiting proliferation and migration, and inducing apoptosis and cell cycle arrest in MCF-7 and MIA-PaCa-2 cells. With the help of network pharmacology analysis, apoptosis-related proteins were selected and further tested by western blot assay. The inhibition of PI3K/AKT and an increase in the levels of Bax/Bcl-2 ratio, Cyt-C, cleaved-Caspase-9, cleaved-Caspase-3 and cleaved-PARP was observed, indicating that EpskA21 induced apoptosis through the mitochondrial pathway. Given that an increase in DR5 expression and activated Caspase-8 were also observed, the extrinsic apoptosis pathway might also be related to the antitumor effect.

Isosteric Replacement of Sulfur to Selenium in a Thiosemicarbazone: Promotion of Zn(II) Complex Dissociation and Transmetalation to Augment Anticancer Efficacy.

We implemented isosteric replacement of sulfur to selenium in a novel thiosemicarbazone (PPTP4c4mT) to create a selenosemicarbazone (PPTP4c4mSe) that demonstrates potentiated anticancer efficacy and selectivity. Their design specifically incorporated cyclohexyl and styryl moieties to sterically inhibit the approach of their Fe(III) complexes to the oxy-myoglobin heme plane. Importantly, in contrast to the Fe(III) complexes of the clinically trialed thiosemicarbazones Triapine, COTI-2, and DpC, the Fe(III) complexes of PPTP4c4mT and PPTP4c4mSe did not induce detrimental oxy-myoglobin oxidation. Furthermore, PPTP4c4mSe demonstrated more potent antiproliferative activity than the homologous thiosemicarbazone, PPTP4c4mT, with their selectivity being superior or similar, respectively, to the clinically trialed thiosemicarbazone, COTI-2. An advantageous property of the selenosemicarbazone Zn(II) complexes relative to their thiosemicarbazone analogues was their greater transmetalation to Cu(II) complexes in lysosomes. This latter effect probably promoted their antiproliferative activity. Both ligands down-regulated multiple key receptors that display inter-receptor cooperation that leads to aggressive and resistant breast cancer.

Discovery and mechanistic insights into thieno[3,2-d]pyrimidine and heterocyclic fused pyrimidines inhibitors targeting tubulin for cancer therapy

Guided by the X-ray cocrystal structure of the lead compound 4a, we developed a series of thieno[3,2-d]pyrimidine and heterocyclic fused pyrimidines demonstrating potent antiproliferative activity against four tumor cell lines. Two analogs, 13 and 25d, exhibited IC50 values around 1 nM and overcame P-glycoprotein (P-gp)-mediated multidrug resistance (MDR). At low concentrations, 13 and 25d inhibited both the colony formation of SKOV3 cells in vitro and tubulin polymerization. Furthermore, mechanistic studies showed that 13 and 25d induced G2/M phase arrest and apoptosis in SKOV3 cells, as well as dose-dependent inhibition of tumor cell migration and invasion at low concentrations. Most notably, the X-ray cocrystal structures of compounds 4a, 25a, and the optimal molecule 13 in complex with tubulin were elucidated. This study identifies thieno[3,2-d]pyrimidine and heterocyclic fused pyrimidines as representatives of colchicine-binding site inhibitors (CBSIs) with potent antiproliferative activity.

Design, synthesis and antitumor activities of phthalazinone derivatives as PARP-1 inhibitors and PARP-1/HDAC-1 inhibitors

In recent years, poly(ADP-ribose)polymerase-1 (PARP-1) and histone deacetylase (HDAC) have emerged as significant targets in tumor therapy, garnering widespread attention. In this study, we designed and synthesized two novel phthalazinone PARP-1 inhibitors and dual PARP-1/HDAC-1 inhibitors, named DLC-1–46 containing dithiocarboxylate fragments and DLC-47–63 containing hydroxamic acid fragments, and evaluated their inhibitory activities on enzymes and cells. Among the PARP-1 inhibitors, most compounds exhibited high inhibitory activity against the PARP-1 enzyme, with DLC-1–6 being particularly notable, showing IC50 values <0.2 nM. Notably, DLC-1 demonstrated significant anti-proliferative activity, with IC50 values for inhibiting the proliferation of MDA-MB-436, MDA-MB-231, and MCF-7 cells reaching 0.08, 26.39, and 1.01 μM, respectively. Further investigation revealed that DLC-1 arrested MDA-MB-231 cells in the G1 phase and induced apoptosis in a dose-dependent manner. Among the designed dual PARP-1/HDAC-1 inhibitors, several compounds exhibited potent dual-target inhibitory activity, with DLC-49 displaying IC50 values of 0.53 nM and 17 nM for PARP-1 and HDAC-1, respectively. DLC-50 demonstrated the most potent anti-proliferative activity, with IC50 values for inhibiting the proliferation of MDA-MB-436, MDA-MB-231, and MCF-7 cells at 0.30, 2.70, and 2.41 μM, respectively. Cell cycle arrest and apoptosis assays indicated that DLC-50 arrested the cell cycle in the G2 phase and induced apoptosis in HCT-116 cells. Our findings present a novel avenue for further exploration of PARP-1 inhibitors and dual PARP-1/HDAC-1 inhibitors.

Benzimidazole-based structure optimization to discover novel anti-gastric cancer agents targeting ROS/MAPK pathway.

Given the malignancy of gastric cancer, developing highly effective and low-toxic targeted drugs is essential to prolong patient survival and improve patient outcomes. In this study, we conducted structural optimizations based on the benzimidazole scaffold. Notably, compound 8 f presented the most potent antiproliferative activity in MGC803 cells and induced cell cycle arrest at the G0/G1 phase. Further mechanistic studies demonstrated that compound 8 f caused the apoptosis of MGC803 cells by elevating intracellular reactive oxygen species (ROS) levels and activating the mitogen-activated protein kinase (MAPK) signaling pathway, accompanied by corresponding markers change. In vivo investigations additionally validated the inhibitory effect of compound 8 f on tumor growth in xenograft models bearing MGC803 cells without obvious toxicity. Our studies suggest that compound 8 f holds promise as a potential and safe lead compound for developing anti-gastric cancer agents.

Anti-Cancer Activity of Synthesized 5-Benzyl juglone on Selected Human Cancer Cell Lines.

Cancer is a malignant disease that causes millions of deaths each year worldwide. As one of the cancer therapeutic strategies, chemotherapy is a means to destroy rapidly dividing cells. The main problem with cancer chemotherapy is the lack of selectivity of conventional chemotherapeutic drugs, leading to toxicity towards normal cells. Therefore, the discovery of anti-cancer agents with selectivity for fast-growing cancer cells is desirable. In this study, we report the synthesis and identification of synthesized 5-benzyl juglone as a potential anticancer agent with selectivity toward certain cancer cell lines. An efficient synthetic method for 5-benzyl juglone was established. The proliferation of cancer cell lines and a normal cell line treated by the target compound was studied using an MTT assay. In addition, the cell cycle arrest and apoptosis were determined by flow cytometry. Based on the Diels-Alder (D-A) reaction between 3,6-dimethoxy benzyne intermediate and furan, further acid-catalyzed intramolecular rearrangement, and CAN-mediated oxidation, a convenient synthesis of 5-benzyl juglone was achieved with high overall yield. The results from in vitro biological evaluation indicated that the juglone derivative exhibited potent antiproliferative activity against HCT-15 human colorectal cancer cells with an IC50 value of 12.27 μM. It exerted high inhibitory activity toward MCF-7 human breast cancer cells and, to a much lesser extent, to corresponding MCF-10A human breast epithelial normal cells with an IC50 ratio (IC50 in MCF-7 divided by IC50 in MCF-10A) of 0.62. The mechanistic investigations indicated that 5-benzyl juglone could induce cell cycle arrest at the G0/G1 phase and promote apoptosis of HCT-15 cells. The apoptotic effects possibly contributed to its higher selectivity toward cancer cells than normal cell lines.

Preclinical efficacy of potent and selective menin-KMT2A inhibitor JNJ-75276617 in KMT2A- and NPM1-altered leukemias

The interaction between menin and histone-lysine N-methyltransferase 2A (KMT2A) is a critical dependency for KMT2A- or nucleophosmin 1 (NPM1)-altered leukemias and an emerging opportunity for therapeutic development. JNJ-75276617 is a novel, orally bioavailable, potent, and selective protein-protein interaction inhibitor of the binding between menin and KMT2A. In KMT2A-rearranged (KMT2A-r) and NPM1-mutant (NPM1c) AML cells, JNJ-75276617 inhibited the association of the menin-KMT2A complex with chromatin at target gene promoters, resulting in reduced expression of several menin-KMT2A target genes, including MEIS1 and FLT3. JNJ-75276617 displayed potent anti-proliferative activity across several AML and ALL cell lines and patient samples harboring KMT2A- or NPM1-alterations in vitro. In xenograft models of AML and ALL, JNJ-75276617 reduced leukemic burden and provided a significant dose-dependent survival benefit accompanied by expression changes of menin-KMT2A target genes. JNJ-75276617 demonstrated synergistic effects with gilteritinib in vitro in AML cells harboring KMT2A-r. JNJ-75276617 further exhibited synergistic effects with venetoclax and azacitidine in AML cells bearing KMT2A-r in vitro, and significantly increased survival in mice. Interestingly, JNJ-75276617 showed potent anti-proliferative activity in cell lines engineered with recently discovered mutations (MEN1M327I or MEN1T349M) that developed in patients refractory to the menin-KMT2A inhibitor revumenib. A co-crystal structure of menin in complex with JNJ-75276617 indicates a unique binding mode distinct from other menin-KMT2A inhibitors, including revumenib. JNJ-75276617 is being clinically investigated for acute leukemias harboring KMT2A or NPM1 alterations, as a monotherapy for relapsed/refractory (R/R) acute leukemia (NCT04811560), or in combination with AML-directed therapies (NCT05453903).

Novel Hsp90-Targeting PROTACs: Enhanced synergy with cisplatin in combination therapy of cervical cancer

The development of effective drugs for cervical cancer is urgently required because of its high mortality rate and the limited treatment options. Herein, we report the design, synthesis, and evaluation of a series of novel and effective Hsp90-targeting PROTACs. These compounds exhibited potent anti-proliferative activity against cervical cancer cells with low IC50 values. Compound lw13 effectively degraded Hsp90 at a concentration of only 0.05 μM. In addition, it can inhibit the metastasis of cancer cells and induce significant cell cycle arrest and apoptosis. Furthermore, lw13 demonstrated remarkable antitumor activity both in vitro and in vivo, and has a synergistic effect in combination with cisplatin. Moreover, lw13 can prevent the activation of the HER2/AKT/mTOR signaling pathway by indirectly reducing the levels of HER2 and AKT. This study paves the way for cancer treatment and provides valuable insights into the combination therapy of cervical cancer.

A first-in-human, phase 1, dose escalation study of SGR-2921 as monotherapy in patients with relapsed/refractory acute myeloid leukemia or myelodysplastic syndrome.

TPS6590 Background: Cell division cycle 7-related protein kinase (CDC7) is a cell cycle kinase that maintains DNA replication by phosphorylation and activation of the minichromosome maintenance protein 2 and 4 (MCMs), components of the replicative DNA helicase. Due to the CDC7's central role in maintaining replication fork integrity, chemical inhibition of CDC7 can ultimately lead to cancer cell death. SGR-2921 is an oral, small molecule inhibitor of CDC7. Preclinical studies demonstrate that SGR-2921 has potent anti-proliferative activity in AML cell lines representative of difficult to treat patient populations, agnostic of serious mutations (including those with p53 mutations), BTK resistance, and multiple prior lines of treatment. This anti-tumor activity has also been demonstrated in cell line-derived xenograft (CDX) and patient-derived xenograft (PDX) AML models. Methods: This is a phase 1, FIH, open-label, single-agent, two-arm, dose escalation study (NCT#05961839) designed to evaluate safety and tolerability and identify the recommended phase 2 dose (RP2D) of SGR-2921 as monotherapy in subjects with relapsed or refractory (R/R) AML, high risk (HR) MDS, or very high risk (VHR) MDS. The study utilizes an accelerated titration design with single patient cohorts that transitions to a 3+3 design once a single Grade 2 event is observed. This is a multicenter global study (US, Spain and France). SGR-2921 will be administered orally, once daily, utilizing a 5-day on and 9-day off dosing schedule over a 28-day cycle. A maximum of 144 patients will be enrolled into dose escalation and exploratory cohorts. To evaluate the effect of CYP3A4 inhibition on SGR-2921 exposure, subjects will be enrolled into one of two staggered, parallel study treatment arms, according to concomitant administration with (Arm B) or without (Arm A) azole antifungals that are strong CYP3A4 inhibitors. A single dose PK run-in will be required for subjects enrolled into the first 3 cohorts of each treatment arm. Subjects will be treated at increasing doses of SGR-2921 until the maximum tolerated dose (MTD) is exceeded. A RP2D will be selected from one of the tolerable dose levels. Key study inclusion criteria include: Age ≥ 18 years of age; Life expectancy ≥ 8 weeks; Confirmed diagnosis of R/R AML or HR and VHR MDS; Eastern Cooperative Oncology Group (ECOG) performance status ≤ 2. Key study exclusion criteria include: Active malignancies not related to AML or MDS within two years prior to the first dose or requiring ongoing treatment; active CNS leukemia; QTcF ≥470 msec. The primary objectives are to evaluate the safety and tolerability of SGR-2921 as monotherapy and to identify the RP2D. Secondary objectives include evaluating SGR-2921 pharmacokinetics and investigating preliminary antitumor activity. Clinical trial information: NCT05961839 .

Design, synthesis and biological evaluation of indoline-maleimide conjugates as potential antitumor agents for the treatment of colorectal cancer

An efficient protocol for direct coupling of maleimides and indolines at the C7-position was achieved under Rh(III) catalysis. Thirty four novel indoline-maleimide conjugates were prepared in good to excellent yields using this method. All compounds were evaluated for their anti-proliferative effect against colorectal cell lines. Among them, compound 3ab showed the most potent anti-proliferative activity against the CRC cells, and displayed low toxicity in the normal cell. Further investigation indicated that 3ab could effectively suppress the proliferation and migration of CRC cells, along with inducing cell cycle arrest and apoptosis. Mechanistic studies revealed that compound 3ab inhibited the proliferation of CRC cells via suppressing the AKT/GSK-3β pathway. In vivo evaluation demonstrated remarkable antitumor effect of 3ab (10 mg/kg) in the HCT116 xenograft model with no obvious toxicity, which is superior to that of 5-Fluorouracil (20 mg/kg). Therefore, conjugate 3ab could be considered as a potential CRC therapy agent for further development.

A first-in-human, phase 1, dose escalation study of SGR-2921 as monotherapy in patients with relapsed/refractory acute myeloid leukemia or myelodysplastic syndrome.

TPS6590 Background: Cell division cycle 7-related protein kinase (CDC7) is a cell cycle kinase that maintains DNA replication by phosphorylation and activation of the minichromosome maintenance protein 2 and 4 (MCMs), components of the replicative DNA helicase. Due to the CDC7's central role in maintaining replication fork integrity, chemical inhibition of CDC7 can ultimately lead to cancer cell death. SGR-2921 is an oral, small molecule inhibitor of CDC7. Preclinical studies demonstrate that SGR-2921 has potent anti-proliferative activity in AML cell lines representative of difficult to treat patient populations, agnostic of serious mutations (including those with p53 mutations), BTK resistance, and multiple prior lines of treatment. This anti-tumor activity has also been demonstrated in cell line-derived xenograft (CDX) and patient-derived xenograft (PDX) AML models. Methods: This is a phase 1, FIH, open-label, single-agent, two-arm, dose escalation study (NCT#05961839) designed to evaluate safety and tolerability and identify the recommended phase 2 dose (RP2D) of SGR-2921 as monotherapy in subjects with relapsed or refractory (R/R) AML, high risk (HR) MDS, or very high risk (VHR) MDS. The study utilizes an accelerated titration design with single patient cohorts that transitions to a 3+3 design once a single Grade 2 event is observed. This is a multicenter global study (US, Spain and France). SGR-2921 will be administered orally, once daily, utilizing a 5-day on and 9-day off dosing schedule over a 28-day cycle. A maximum of 144 patients will be enrolled into dose escalation and exploratory cohorts. To evaluate the effect of CYP3A4 inhibition on SGR-2921 exposure, subjects will be enrolled into one of two staggered, parallel study treatment arms, according to concomitant administration with (Arm B) or without (Arm A) azole antifungals that are strong CYP3A4 inhibitors. A single dose PK run-in will be required for subjects enrolled into the first 3 cohorts of each treatment arm. Subjects will be treated at increasing doses of SGR-2921 until the maximum tolerated dose (MTD) is exceeded. A RP2D will be selected from one of the tolerable dose levels. Key study inclusion criteria include: Age ≥ 18 years of age; Life expectancy ≥ 8 weeks; Confirmed diagnosis of R/R AML or HR and VHR MDS; Eastern Cooperative Oncology Group (ECOG) performance status ≤ 2. Key study exclusion criteria include: Active malignancies not related to AML or MDS within two years prior to the first dose or requiring ongoing treatment; active CNS leukemia; QTcF ≥470 msec. The primary objectives are to evaluate the safety and tolerability of SGR-2921 as monotherapy and to identify the RP2D. Secondary objectives include evaluating SGR-2921 pharmacokinetics and investigating preliminary antitumor activity. Clinical trial information: NCT05961839 .

Design, synthesis, biological evaluation, and in silico studies of novel pyridopyridine derivatives as anticancer candidates targeting FMS kinase

Design and synthesis of novel 4-carboxamidopyrido[3,2-b]pyridine derivatives as novel rigid analogues of sorafenib are reported herein. The target compounds showed potent antiproliferative activities against a panel of NCI-60 cancer cell lines as well as hepatocellular carcinoma cell line. Compounds 8g and 9f were among the most promising derivatives in terms of effectiveness and safety. Therefore, they were further examined to demonstrate their ability to induce apoptosis and alter cell cycle progression in hepatocellular carcinoma cells. The most potent compounds were tested against a panel of kinases that indicated their selectivity against FMS kinase. Compounds 8g and 8h showed the most potent activities against FMS kinase with IC50 values of 21.5 and 73.9 nM, respectively. The two compounds were also tested in NanoBRET assay to investigate their ability to inhibit FMS kinase in cells (IC50 = 563 nM (8g) and 1347 nM (8h) vs. IC50 = 1654 nM for sorafenib). Furthermore, compounds 8g and 8h possess potent inhibitory activities against macrophages when investigated in bone marrow-derived macrophages (BMDM) assay (IC50 = 56 nM and 167 nM, respectively, 164 nM for sorafenib). The safety and selectivity of these compounds were confirmed when tested against normal cell lines. Their safety profile was further confirmed using hERG assay. In silico studies were carried out to investigate their binding modes in the active site of FMS kinase, and to develop a QSAR model for these new motifs.

Structural characterization and bioactivities of maize bran feruloylated arabinoxylan and oligosaccharides obtained by a combined hydrothermal and enzymatic pre-treatment

Feruloylated arabinoxylans (F-AX) are gaining importance due to their immense health benefits as nutraceuticals. In the current study, we extracted F-AX from maize bran by a combination of hydrothermal pre-treatment and xylanase and cellulase double enzymatic digestion and studied them in detail. The F-AX composition included carbohydrate (533.74 ± 7.59 mg/g), and phenolic acid (153.71 ± 3.55 mg/g) with an arabinoxylan percentage of 74.17% and degree of substitution of 0.99. Ferulic acid was the major phenolic acid found esterified to arabinose. The GC, FTIR, UPLC, and methylation analysis revealed the typical structure of arabinoxylan with bound ferulic acid and a highly substituted xylopyranose backbone. The LC-MS/MS analysis revealed the structure of F-AXOS, which were the predominant oligosaccharides in the purified fraction. The F-AX showed potent antioxidant activity (DPPH, ABTS, and FRAP) and could effectively inhibit the formation of advanced glycation end products (argpyrimidine, pentosidine, and vesperlysine) and protein oxidation products (dityrosine and N′-formylkynurenine). F-AX also showed potent antiproliferative activity against the human colon cancer cells - Colo 205 and HCT 116. The current study revealed that the combined extraction method has yielded a unique blend of F-AX with bioactivities and these molecules have the potential to be used in the development of innovative functional foods.

Design, concise synthesis and evaluation of novel amide-based combretastatin A-4 analogues as potent tubulin inhibitors

As our ongoing work, a novel series of the amide-based CA-4 analogues were successfully designed, synthesized, and explored for their biological evaluation. Among these compounds, 7d and 8a illustrated most potent antiproliferative activity toward A549, HeLa, HCT116, and HT-29 cell lines. Most importantly, these two compounds didn’t display noticeable cytotoxic activity on the non-tumoural cell line HEK-293. Further mechanism studies revealed that analogue 8a was identified as a novel tubulin polymerization inhibitor with an IC50 value of 6.90 μM, which is comparable with CA-4. The subsequent investigations unveiled that analogue 8a not only effectively caused cell cycle arrest at the G2/M phase but also induced apoptosis in A549 cells via a concentration-dependent manner. The molecular docking revealed that 8a could occupy well the colchicine-binding site of tubulin. Collectively, these findings indicate that amide-based CA-4 scaffold could be worthy of further evaluation for development of novel tubulin inhibitors with improved safety profile.

New Thieno[2,3-d]pyrimidines as Anticancer VEGFR-2 Inhibitors with Apoptosis Induction: Design, Synthesis, and Biological and In Silico Studies.

Vascular endothelial growth factor receptor-2 (VEGFR-2) is a critical protein involved in tumor progression, making it an attractive target for cancer therapy. This study aimed to synthesize and evaluate novel thieno[2,3-d]pyrimidine analogues as potential anticancer VEGFR-2 inhibitors. The thieno[2,3-d]pyrimidine analogues were synthesized following the pharmacophoric features of VEGFR-2 inhibitors. The anticancer potential was assessed against PC3 and HepG2 cell lines. The VEGFR-2 inhibition was evaluated through IC50 determination. Cell cycle analysis and apoptosis assays were performed to elucidate the mechanisms of action. Molecular docking, molecular dynamics simulations, MM-GBSA, and PLIP studies were conducted to investigate the binding affinities and interactions with VEGFR-2. Additionally, in silico ADMET studies were performed. Compound 8b demonstrated significant anti-proliferative activities with IC50 values of 16.35 μM and 8.24 μM against PC3 and HepG2 cell lines, respectively, surpassing sorafenib and exhibiting enhanced selectivity indices. Furthermore, compound 8b showed an IC50 value of 73 nM for VEGFR-2 inhibition. Cell cycle analysis revealed G2-M phase arrest, while apoptosis assays demonstrated increased apoptosis in HepG2 cells. Molecular docking and dynamic simulations confirmed the binding affinity and interaction of compound 8b with VEGFR-2, supported by MMGBSA and PLIP studies. In silico ADMET studies indicated the drug development potential of the synthesized thieno[2,3-d]pyrimidines. The study highlights compound 8b as a promising VEGFR-2 inhibitor with potent anti-proliferative activities. Its mechanism of action involves cell cycle arrest and induction of apoptosis. Further, molecular docking and dynamic simulations support the strong binding affinity of compound 8b to VEGFR-2.

Host-specific endophytes of Momordica charantia: A promising source for affordable lung cancer therapeutics

Endophyte-host interactions lead to the production of various bioactive compounds. Thus, endophytes from a medicinal plant such as Momordica charantia, can be promising candidates for producing pharmacological compounds. Our study therefore aims to evaluate these endophytes as sustainable sources of potential low-cost lung cancer drugs. We determined the endophytes associated with M. charantia (fruit and leaf) and assessed anti-inflammatory, antioxidant and antiproliferative potential against NCI-H23 lung cancer cells. LC-Q-TOF-MS of the endophyte extracts was conducted to determine the metabolite profile.Leaf endophyte F. circinatum showed anti-inflammatory (114.29 %), antioxidant (IC50=27.39 µg/ml) and antiproliferative activity (IC50=98.62 µl/ml) with decreased Beclin1 expression (autophagy regulator) in NCI-H23 cells. It produced five anticancer compounds namely linamarin, xestoaminol C, phytosphingosine, cucurbitacin E and margarolic acid. Fruit endophyte E. fergusonii also showed significant antiproliferative potential (IC50=170.8 µl/ml) with upregulated apoptosis regulator Bcl2 expression. It produced compounds such as eplerenone, kuguacin C and H. With the production of triterpenoids momordicine I, cucurbitacin E and kuguaglycoside A, leaf endophyte A. faecalis showed antioxidant potential (IC50=29.65 µg/ml) but limited antiproliferative activity. This is the first report of endophytes-mediated biosynthesis of host-specific compounds in M. charantia including momordicine I, cucurbitacin E and kuguacins, which are known to have anti-cancer properties. Thus, these medicinal plant endophytes can be low-cost sustainable candidates with anti-cancerous potential, especially against lung cancer.

Two-Phase Electrosynthesis of Dihydroxycoumestans: Discovery of a New Scaffold for Topoisomerase I Poison.

Coumestan represents a biologically relevant structural motif distributed in a number of natural products, and the rapid construction of related derivatives as well as the characterization of targets would accelerate lead compound discovery in medicinal chemistry. In this work, a general and scalable approach to 8,9-dihydroxycoumestans via two-electrode constant current electrolysis was developed. The application of a two-phase (aqueous/organic) system plays a crucial role for success, protecting the sensitive o-benzoquinone intermediates from over-oxidation. Based on the structurally diverse products, a primary SAR study on coumestan scaffold was completed, and compound 3 r exhibited potent antiproliferative activities and a robust topoisomerase I (Top1) inhibitory activity. Further mechanism studies demonstrates that compound 3 r was a novel Top1 poison, which might open an avenue for the development of Top1-targeted antitumor agent.

Synthesis and antitumor activities of novel 3-(6-aminopyridin-3-yl)benzamide derivatives: Inducing cell cycle arrest and apoptosis via AURKB transcription inhibition

Here, a series of 3-(6-aminopyridin-3-yl) benzamide derivatives were designed and synthesized. Cell viability assay indicated that most compounds exhibited potent antiproliferative activity against all the tested cancer cells. Among them, compound 7l displayed the best antiproliferative activity particularly in A549 cells, with an IC50 value of 0.04 ± 0.01 μM. RNA-seq analysis was employed to explore the potential pathways related to the antiproliferative activity of compound 7l. The data revealed that 7l exerted antiproliferative activity mainly by regulating cell cycle, DNA replication and p53 signaling pathway. Indeed, compound 7l induced G2/M phase arrest by AURKB transcription inhibition and resulted in cell apoptosis via p53 signaling pathway. Most importantly, compound 7l demonstrated potent antitumor activity in A549 xenograft tumor model. Collectively, 7l might be a promising lead compound for the development of new therapeutic agents for AURKB overexpressed or mutated cancers.