SF-268 Cell Research Articles

Ferroptosis - a potential feature underlying neratinib-induced colonic epithelial injury.

Neratinib, a small-molecule tyrosine kinase inhibitor (TKI) that irreversibly binds to human epidermal growth factor receptors 1, 2 and 4 (HER1/2/4), is an approved extended adjuvant therapy for patients with HER2-amplified or -overexpressed (HER2-positive) breast cancers. Patients receiving neratinib may experience mild-to-severe symptoms of gut toxicity including abdominal pain and diarrhoea. Despite being a highly prevalent complication in gut health, the biological processes underlying neratinib-induced gut injury, especially in the colon, remains unclear. Real-time quantitative polymerase chain reaction (RT-qPCR) and histology were integrated to study the effect of, and type of cell death induced by neratinib on colonic tissues collected from female Albino Wistar rats dosed with neratinib (50mg/kg) daily for 28 days. Additionally, previously published bulk RNA-sequencing and CRISPR-screening datasets on human glioblastoma SF268 cell line and glioblastoma T895 xenograft, and mouse TBCP1 breast cancer cell line were leveraged to elucidate potential mechanisms of neratinib-induced cell death. The severity of colonic epithelial injury, especially degeneration of surface lining colonocytes and infiltration of immune cells, was more pronounced in the distal colon than the proximal colon. Sequencing showed that apoptotic gene signature was enriched in neratinib-treated SF268 cells while ferroptotic gene signature was enriched in neratinib-treated TBCP1 cells and T895 xenograft. However, we found that ferroptosis, but less likely apoptosis, was a potential histopathological feature underlying colonic injury in rats treated with neratinib. Ferroptosis is a potential feature of neratinib-induced colonic injury and that targeting molecular machinery governing neratinib-induced ferroptosis may represent an attractive therapeutic approach to ameliorate symptoms of gut toxicity.

Irpexols A-C, xanthone derivatives from the endophyte fungus Irpex laceratus A878

Three new xanthone derivatives irpexols A-C (1–3) and five known xanthones including three dimeric ones were successfully isolated from Irpex laceratus A878, an endophytic fungus of the family Irpicaceae from the medicinal plant Pogostemon cablin (Blanco) Bentham (Lamiaceae). The structures of these compounds were elucidated by extensive spectroscopic analyses including ultraviolet-visible spectroscopy (UV), infrared spectroscopy (IR), mass spectrometry (MS), and nuclear magnetic resonance (NMR). All of the three new compounds (1–3) share a de-aromatic and highly‑oxygenated xanthone skeleton. In addition, the cytotoxic activity of compounds 1–8 were evaluated against SF-268, MCF-7, HepG2, and A549 tumor cell lines. The results revealed that compound 6 showed moderate cytotoxic activity with the IC50 values ranging from 24.83 to 45.46 μM, while the IC50 values of the positive control adriamycin was ranging from 1.11 to 1.44 μM.

Pararorine A, isoindolinone alkaloid from the endophytic fungus Paramyrothecium roridum and its anti-tumor activity

Pararorine A, a new isoindolinone alkaloid was isolated from Paramyrothecium roridum, an endophytic fungus from the medicinal plant Gynochthodes officinalis (F.C. How) Razafim. & B. Bremer. The structure of this compound was elucidated by extensive spectroscopic (UV, IR, MS, and NMR) analyses. In addition, the antitumor activity of pararorine A was evaluated against SF-268, MCF-7, HepG2, and A549 tumor cell lines. The results revealed that pararorine A exhibited potent antitumor activities with the IC50 values ranging from 1.69 to 8.95 μM. Moreover, the tumor cell inhibitory activity of pararorine A was evidenced by promoting cytochrome C release and cell cycle arrest as well as the induction of apoptosis by the up-regulation of the protein expressions of JNK and Bax through PARP-cleavage and caspase 3-cleavage.

Effect of REG3A on proliferation and invasion of glioma cells by regulating PI3K/Akt signaling pathway

Objective: To investigate the effects of regenerating islet-derived protein 3A (REG3A) on the proliferation and invasion of glioma cells and its molecular mechanism. Methods: Five low-grade, five high-grade glioma tissues and ten adjacent tissues from glioma patients who underwent surgery at Linyi People's Hospital from October 17, 2017 to October 18, 2018 were collected. Human glioma cell lines (SF295, U251, TG905, A172, CRT) and a primary glioma cell line PT-1 were cultured in vitro. The protein and mRNA expressions of REG3A in these tissues and glioma cell lines were detected by Western blot and reverse transcription-quantitative real-time polymerase chain reaction (RT-qPCR). SF295 cells were infected with lentivirus and labeled as REG3A plasmid transfection group, and the TG905 cells were transfected with si-REG3A by liposome transfection reagent and labeled as si-REG3A transfection group. At the same time, the empty transfection control and blank control groups were set up. Glioma cells were treated with REG3A recombinant protein alone or in combination with Akt1/2 inhibitors. Cell counting kit-8 (CCK-8) and cell scratch assay were used to detect cell proliferation and invasion, respectively. Western blot was used to detect the protein expression of N-cadherin, vimentin and phosphorylation of Akt (p-Akt) in REG3A overexpressed and knockdown glioma cells. Results: RT-qPCR results showed that the mRNA expression levels of REG3A in glioma cells in each group were U251 (2.129±0.13), TG905 (2.22±0.59), CRT (5.02±0.31), A172 (6.62±1.34) and PT-1 (9.18±0.61), respectively, higher than its expression in SF295 cells (1.00±0.18, P<0.001). The mRNA expression level of REG3A in high-grade glioma tissue samples (3.18±2.92) was higher than that in the control group (1.00±1.14, P=0.031) and low-grade glioma group (0.90±0.67, P=0.014). The results of western blot and immunohistochemical staining were consistent with that of RT-qPCR. The migration rate of cells in si-REG3A transfection group [(60.57±5.30)%] was lower than that of the empty transfection group [(84.18±13.63)% (P=0.038)] and blank control group [(79.65±12.09)% (P=0.076)]. The results of the scratch experiment showed that the migration rate of cells in REG3A plasmid transfected cells in the SF295 group was (96.05±6.41)%, which was significantly higher than that of empty transfected cells [(74.47±8.23)%, P=0.021)]. REG3A recombinant protein could up-regulate the expression of N-cadherin, vimentin and p-Akt in SF295 cells. Compared with the control group [(100.00±2.53)%], the proliferation rate in the REG3A recombinant protein group [(117.70±10.24)%] was significantly up-regulated, and the proliferation rate in the REG3A recombinant protein+ Akt inhibitor group [(98.31±3.64)%] was significantly lower than that of the REG3A recombinant protein group (P=0.017). The migration rate of the REG3A recombinant protein+ Akt inhibitor group was (63.35±4.06)%, which was significantly lower than (89.26±11.07)% of the REG3A recombinant protein group (P=0.019). Conclusion: REG3A can promote the proliferation and invasion of human glioma cells by activating the PI3K/Akt signaling pathway.

Scutellarin Inhibits Glioblastoma Growth in a Dose-dependent Manner by Suppressing the p63 Signaling Pathway.

Although scutellarin has been extensively investigated, its effects on glioma are unclear. This study intended to reveal this regulation and the underlying mechanisms. The U251, M059K, and SF-295 cell lines were treated with gradient concentrations of scutellarin and then IC50 was calculated. SF-295 cells selected for subsequent procedures were treated with four concentrations of scutellarin. Then, proliferation, apoptosis, and cell cycle, as well as the protein and mRNA expression of significantly differentially expressed genes identified by next-generation sequencing (NGS), were examined. The curative effect of scutellarin was validated by 5-FU as the positive control. Scutellarin inhibited proliferation and induced apoptosis and G2/M cell cycle arrest in the SF-295 cell line in a dose-dependent manner. The effect of scutellarin was similar to but significantly weaker than the effect of 5-FU. The NGS results showed that genes associated with anti-apoptosis signaling pathways were significantly reduced after treatment. The Western blotting results indicated that the expressions of TP63/BIRC3/TRAF1/Bcl-2 were reduced in a dose-dependent manner, as well as the mRNA levels determined by qRT‒PCR. Our original conclusion revealed that scutellarin may inhibit glioma growth in a dose-dependent manner via the p63 signaling pathway which may provide a potential medicine for glioma chemotherapy.

Overcoming temozolomide resistance in glioblastoma through selective inhibition of phosphoinositide 3-kinase catalytic subunit.

e14045 Background: Glioblastoma is one of medicine's most difficult-to-treat cancers due to its inevitable resistance to chemotherapies, such as temozolomide (TMZ). Tumor resistance to TMZ often comes from overactivation of phosphoinositide 3-kinase (PI3K), making this enzyme an ideal anti-cancer drug target; however, in practice, non-selective targeting of PI3K has resulted in undesirable clinical outcomes. Therefore, it is necessary to explore each subunit of PI3K to determine their effect on chemoresistance in order to develop therapeutics to overcome said resistance. PI3K has four homologous yet functionally distinct catalytic subunits: p110α, p110β, p110δ, and p110γ. Preliminary in silico analysis of each subunit has demonstrated that p110β is more highly expressed in glioblastoma than the other subunits. Here we report that TMZ resistance in glioblastoma is driven primarily by activation of p110β. Methods: Glioblastoma cell lines with high p110β levels (SF295 and U87MG) and low p110β levels (A172 and LN229) were cultured. CRISPR-Cas9 was used to knockout p110α, p110β, or p110δ in cultured cell lines. The viability of cultured cells was measured using an MTS viability assay. Newly cultured wild-type cells were treated with IC50 doses of selective p110β inhibitor TGX-221 and TMZ. Mice bearing SF295 xenograft tumors were treated with DMSO, TGX-221, and/or TMZ. A Bliss model of independence was used to assess the association between TGX-221 and TMZ with synergistic and antagonistic patterns measured using excess over Bliss (EOB) scores. Results: There was a significant reduction in viability among SF295 p110β-knockout cells (p &lt; 0.001) and an additive cytotoxic effect following treatment with TMZ. The LN229 p110β-knockout cells treated with TMZ did not reduce cell viability. Similarly, no substantial declines in viability were observed in the p110α- or p110δ-knockout cells before or after TMZ treatment in either cell line. In newly cultured wild-type p110β-high and p110β-low glioblastoma cell lines, TGX-221 or TMZ alone were insufficient to inhibit cell viability; however, when combined, TGX-221 and TMZ synergistically decreased cell survival with an EOB of 45.5% in U87MG cells and 26.3% in SF295 cells. No additive effects were detected in the p110β-low cell lines following TGX-221 and TMZ treatment. Additionally, TGX-221 combined with TMZ resulted in a drastic reduction in xenograft tumor growth, which was significantly greater than TGX-221 (p &lt; 0.02) or TMZ (p &lt; 0.003) treatment alone. Conclusions: Inhibition of p110β via CRISPR-Cas9 knockout or pharmaceutical blockade restores TMZ sensitivity in p110β-high glioblastoma cells and xenograft glioblastoma tumors. These results demonstrate the varying importance of PI3K catalytic subunits and necessitate further exploration into p110β as a potential drug target to overcome chemoresistance in glioblastoma.

Isolation and identification of novel selective antitumor constituents, sidrin and sidroside, from Zizyphus spina-christi

BackgroundThe leaves of Zizyphus spina-christi (L.) Willd contain several compounds exhibiting different pharmacologic activities. However, studies on the cytotoxic activity of these compounds are limited. ObjectivesWe aimed to investigate and isolate cytotoxic compounds with selective antitumor effects from the leaves of Z. spina-christi using bioassay-guided fractionation of methanol extract. MethodsPowdered, dried leaves were subjected to methanol extraction and fractionated using n-hexane, chloroform, ethyl acetate, and n-butanol. Fractions with positive cytotoxicity against HeLa and THP-1 cell lines were further fractionated and eluted using various concentrations of organic solvents. Active compounds were isolated using different chromatographic methods and their chemical structures were determined using extensive spectroscopic methods, such as 1D NMR (1H NMR, 13C NMR, and DEPT), 2D NMR (COSY, HMBC, and HMQC), HRFAB-MS, and IR. Furthermore, the cytotoxic effects of the isolated compounds were evaluated against 62 tumor cell lines (including HeLa and THP-1) in addition to normal bone marrow cells. ResultsThe chloroform and aqueous methanol fractions of the leaves showed cytotoxic activity. Two compounds were successfully isolated and named “sidrin” (13-β-hydroxy-lup-20(30)-ene-2,3-β-epoxy-28-carboxylate) and “sidroside” (3-O-β-D-glucopyranosyl-(1–3)-α-L-arabinopyranosyl-jujubogenin-20-O-α-L-rhamnopyranoside). Sidrin exhibited cytotoxic activity against the human leukemia (Hl-60, RPMI-8226), lung cancer (A549, EKVX), breast cancer (BT-549, MDA-MB-231/ATCC), colon cancer (KM12), melanoma (M14, SK-MEL-5), and central nervous system (CNS) cancer (SF-295) cell lines, and selectivity was observed against the Hl-60, EKVX, BT-549, KM12, and SF-295 cell lines. In addition, sidrin was more active than sidroside and doxorubicin against the Hl-60 and EKVX cell lines. In contrast, sidrin had a similar effect to doxorubicin against the BT-549 and renal cancer (UO-31) cell lines. Sidroside was more selective against the leukemia (CCRF-CEM, MOLT-4), lung cancer (HOP-92, NCI-H322M), breast cancer (MDA-MB-468), melanoma (LOX IMVI), CNS cancer (SNB-19), ovarian cancer (OVCAR-8), renal cancer (UO-31, RXF 393), and prostate cancer (PC-3) cell lines. Both compounds exhibited similar activity against the breast cancer (MDA-MB-231, T-47D), colon cancer (HCC-2998, HCT-116), ovarian cancer (OVCAR-3), renal cancer (UO-31, 786–0, and SN 12C) cell lines. Normal bone marrow cells were unaffected at the same concentrations of sidrin and sidroside applied to tumor cells. ConclusionsThese results suggest tumor-selective cytotoxicity of sidrin and sidroside.

Secondary metabolites from the leaves of Meliosma rhoifolia and evaluation of their cytotoxic activity

One previously undescribed labdane diterpenoid, meliosmarhoifol (1), together with four known ones, 12R,15-dihydroxylabda-8(17),13E-dien-19-oic acid (2), 18-norlabda-8(17),14-diene-4α,13β-diol (3), 5α,6α-epoxy-(22E,24R)-ergosta-8(14),22-diene-3β,7α-diol (4), 5α,6α-epoxy- (22E,24R)-ergosta-8,22-diene-3β,7α-diol (5), were isolated from the leaves of Meliosma rhoifolia. The structures of all isolates were elucidated on the basis of extensive analyses of spectroscopic data and comparison with literature data. In addition, the cytotoxicity of the isolates was evaluated on the MCF-7, NCI-H460 and SF-268 cell lines. Among them, compounds 2–5 were found to have moderate cytotoxic effects against these three cell lines in vitro. Four constituents, compounds 1, 2, 4 and 5 showed different sensitivities in inhibiting the growth of MCF-7 breast cancer cells, with IC50 values ranging from 4.21 to 25.70 μM, while compound 3 did not show obvious effects. Amount these isolates, meliosmarhoifol (1) showed as the most actively compound against the MCF-7, NCI-H460 and SF-268 cell lines with IC50 values of 4.21, 4.76, and 8.32 μM, respectively.

Cytotoxic pyrone derivatives from the deep-sea-derived fungus Cladosporium halotolerans FS702

Two new compounds (R)-6-((8S)-hydroxypropyl)-2-methyl-5,6-dihydro-4H-pyran-4-one (1) and (R)-6-((8R)-hydroxypropyl)-2-methyl-5,6-dihydro-4H-pyran-4-one (2), together with four known compounds were isolated from the marine-derived fungus Cladosporium halotolerans FS702. The structures of these compounds were determined on the basis of extensive spectroscopic analysis including 1D/2D NMR, IR, UV, HRESIMS, ECD calculations as well as the modified Mosher’s method. Cytotoxic assay results showed that compound 2 had significant cytotoxic activity against SF-268, MCF-7, HepG-2, and A549 cells lines with IC50 values of 0.16, 0.47, 0.33 and 0.23 µM, respectively.

Abstract 3895: Moxidectin unravels the role of Hippo-YAP pathway in maintaining immunity of pediatric glioblastoma

Abstract Pediatric glioblastoma multiforme (GBM) is considered to be the second most lethal childhood cancer type after leukemia. Recent preclinical, clinical and genomic studies have highlighted upon the role of Hippo-Yap pathway in the progression of pediatric GBM. In addition, recent studies have established the role of YAP in creating immune suppressive tumor microenvironment (TME) facilitating drug resistance, recurrence and metastasis of GBM tumors. Herein, we report that ‘moxidectin’ an anti-helminthic drug inhibits the proliferation of SF268, SF295, SF188 and CT-2A Luc GBM cells by inducing apoptosis. Immunoblotting and immunofluorescence microscopy studies show that moxidectin mediates its effects by inhibiting MEK-ERK pathway, a regulator of Hippo-YAP signaling. As a result, moxidectin suppressed the nuclear translocation and transcriptional activity of YAP/TAZ-TEAD complex. Oral administration of 3.5mg/kg moxidectin suppressed the growth of GBM tumors by 90% in intracranial tumor model. Ex-vivo analysis of excised tumors confirmed the observations made in in vitro studies. We further conducted immunophenotyping on the excised tumors from both control and moxidectin treated mice to evaluate the effect of moxidectin on immune cell markers in TME and Tumor Draining Lymph Nodes (TDLNs). Our analysis indicated that treatment with moxidectin suppressed the immune suppressive TME created by GBM tumor. Interestingly, moxidectin enhanced antigen presentation in the TDLN. Indicating that it might play a role in activating the peripheral immune response. Moxidectin is an FDA approved drug and any findings from our research will promote its further investigation as a potential therapeutic agent for GBM patients. Citation Format: Itishree Kaushik, Shreyas Gaikwad, Sanjay K. Srivastava. Moxidectin unravels the role of Hippo-YAP pathway in maintaining immunity of pediatric glioblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 3895.

Abstract 5362: Targeting PIK3CB in glioblastoma

Abstract Background: Glioblastoma (GBM) is the most common and one of the most lethal malignant brain tumors in existence. The poor prognosis of this disease is due in part to tumor recurrence and temozolomide (TMZ) resistance, for which PI3K/AKT pathway overactivation has been implicated. Our work is to demonstrate that p110β inhibition could represent a therapeutic target in sensitizing recurrent tumors to TMZ therapy, and demonstrate the utility of personalized GBM treatments. Objective: We aim to develop a more effective treatment for TMZ resistant GBM patients. We hypothesize that a p110β inhibitor will sensitize resistant GBM cell lines to TMZ therapy. We intend to support this hypothesis by demonstrating that the p110β inhibitor TGX-221 in combination with TMZ will provide a significantly greater level of cytotoxicity on TMZ resistant GBM cell lines than TGX-221 or TMZ monotherapy alone. We also intend to provide further evidence for this therapy by utilizing it to overcome TMZ resistance in glioblastoma stem cells (GSC’s). Methods: We compared the cytotoxicity of TMZ, TGX-221, and a TMZ/TGX-221 combination therapy on p110β-high/TMZ resistant and p110β-low/TMZ sensitive GBM cell lines. Cell viability was determined using the MTS assay. We then tested these reagents on normal human astrocytes to determine any potential dose-limiting off-target effects. Lastly, we tested these reagents using human-derived GSC’s. Results: A statistically significant difference (p &amp;lt; 0.01) in cell viability was found using the TMZ/TGX-221 combination therapy as compared to either TMZ or TGX-221 alone in our TMZ resistant SF295 cells, and a significant different was found between the combination therapy and TMZ monotherapy in our TMZ resistant U87MG cells. No significant difference was found between treatments in our TMZ sensitive A172 cells or normal human astrocytes. Conclusions: The results of our GBM cell line experiments provide support that combination TMZ/TGX-211 is superior in cytotoxicity to either monotherapy alone in TMZ resistant cell lines. This indicates that TGX-211, through p110β inhibition, is able to sensitize resistant cell lines to TMZ therapy. More experiments are ongoing to determine if this effect will also be demonstrated in human-derived GSC’s. Citation Format: Marc R. Fromherz, Kevin J. Pridham, Zhi Sheng. Targeting PIK3CB in glioblastoma [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 5362.

A novel glioblastoma prognostic assay using droplet digital polymerase chain reaction.

e14026 Background: Glioblastoma (GBM) is an incurable brain tumor for which outcomes have seen little improvement in the past 30 years. Despite limited GBM therapies, accurate prognostic tools can be invaluable in informing best course of treatment. Recently, we have identified the GBM progression gene signature (GBM-PGS), a collection of 31 genes that shows superior accuracy at predicting GBM progression compared to existing biomarkers. From GBM-PGS expression, a GBM progression risk score can be calculated to provide clinicians with patient-tailored prognostic information. However, the question remains as to the best way to measure GBM-PGS to create a clinically applicable test. At our disposal are three approaches to quantify gene expression: quantitative polymerase chain reaction (qPCR), droplet digital PCR (ddPCR), and RNA sequencing (RNA seq). We hypothesize that the combination of high accuracy and sensitivity, while also providing absolute quantification, will deliver ddPCR as the best option for creating a rapid clinical test that is scalable for measuring GBM-PGS. Methods: A ddPCR protocol was developed, and cDNA and primer concentrations were optimized using samples from two GBM cell lines (SF295, LN18). To confirm assay accuracy, GBM-PGS was quantified using ddPCR and compared to GBM-PGS expression by qPCR, a protocol that has previously been thoroughly validated. Finally, GBM-PGS expression was measured in patient tumors using ddPCR, and the GBM-PGS risk score algorithm was trained using an RNA seq data set from the Tissue Cancer Genome Atlas (TCGA). Following training, risk scores were calculated for the patient samples using ddPCR-measured GBM-PGS expression. Risk scores were compared with clinical patient survival to determine if GBM-PGS expression measured by ddPCR could predict patient outcomes. Results: Optimal primer concentration (200 nM) and cDNA concentration (1.2 ng/μl) were identified. GBM-PGS expression measured by ddPCR absolute quantification and qPCR Ct value demonstrated a strong correlation in the SF295 (R2 = 0.91) and LN18 (R2 = 0.88) cell lines. GBM-PGS was measured in two patient samples, and the resulting risk scores were calculated as 26.6 and 29.8 (score &gt; 0 = high progression risk; score &lt; 0 = low progression risk) compared to disease free survival times of 12.9 and 10.5 months, respectively, demonstrating an inverse relationship between patient risk score and survival time. Conclusions: Our results demonstrate that we have developed an accurate ddPCR-based assay capable of measuring GBM-PGS in multiple GBM cell lines, and preliminary results suggest that GBM-PGS quantified using ddPCR accurately predicts patient survival.

HOTTIP Mediated Therapy Resistance in Glioma Cells Involves Regulation of EMT-Related miR-10b.

The advanced grade glioblastomas are characterized by dismal five-year survival rates and are associated with worse outcomes. Additionally, resistance to therapies is an additional burden responsible for glioma associated mortality. We studied the resistance against temozolomide (TMZ) as a surrogate to understand the mechanism of therapy resistance in glioma cancer cells. Screening of three glioma cells lines, A172, LN229 and SF268 revealed that SF268 glioma cells were particularly resistant to TMZ with the IC-50 of this cell line for TMZ ten times higher than for the other two cell lines. A role of lncRNAs in glioma progression has been identified in recent years and, therefore, we focused on lncRNAs for their role in regulating TMZ resistance in glioma cancer cells. lncRNA HOTTIP was found to be particularly elevated in SF268 cells and over-expression of HOTTIP in both A172 and LN229 remarkably increased their TMZ IC-50s, along with increased cell proliferation, migration, clonogenicity and markers of angiogenesis and metastasis. As a mechanism we observed increased expression of miRNA-10b and mesenchymal markers Zeb1/Zeb2 and reduced expression of E-cadherin in SF268 cells indicating a role of EMT in TMZ resistance. A172 and LN229 cells with overexpressed HOTTIP also had similarly induced EMT and the elevated miR-10b levels. Further, silencing of miR-10b in HOTTIP overexpressing cells as well as the SF268 cells reversed EMT with associated sensitization of all the tested cells to TMZ. Our results thus present a case for HOTTIP in native as well as acquired resistance of glioma cells against chemotherapy, with a key mechanistic role of EMT and the miR-10b. Thus, HOTTIP as well as miR-10b are critical targets for glioma therapy, and need to be tested further.

Secondary metabolites from a deep-sea derived fungal strain of Phomopsis lithocarpus FS508

One new isoindolinone lactam lithocarlactam A (1) and one new triterpene lithocarin D (2), along with nine known natural products (3–11) were isolated from the broth extract of marine fungus Phomopsis lithocarpus FS508, which was isolated from a deep-sea sediment sample. Their structures were elucidated by interpretation of spectroscopic analysis and comparison with previously published literatures for the known compounds. Moreover, compounds 1 and 2 were evaluated for cytotoxic activity against SF-268, MCF-7, HepG-2, and A549 cell lines. However, both of them showed no activity against the tumor cell lines.

Chevalones H-M: Six New α-Pyrone Meroterpenoids from the Gorgonian Coral-Derived Fungus Aspergillus hiratsukae SCSIO 7S2001.

Six new α-pyrone meroterpenoid chevalones H–M (1–6), together with six known compounds (7–12), were isolated from the gorgonian coral-derived fungus Aspergillus hiratsukae SCSIO 7S2001 collected from Mischief Reef in the South China Sea. Their structures, including absolute configurations, were elucidated on the basis of spectroscopic analysis and X-ray diffraction data. Compounds 1–5 and 7 showed different degrees of antibacterial activity with MIC values of 6.25–100 μg/mL. Compound 8 exhibited potent cytotoxicity against SF-268, MCF-7, and A549 cell lines with IC50 values of 12.75, 9.29, and 20.11 μM, respectively.

RNAseq reveals extensive metabolic disruptions in the sensitive SF-295 cell line treated with schweinfurthins

The schweinfurthin family of natural compounds exhibit a unique and potent differential cytotoxicity against a number of cancer cell lines and may reduce tumor growth in vivo. In some cell lines, such as SF-295 glioma cells, schweinfurthins elicit cytotoxicity at nanomolar concentrations. However, other cell lines, like A549 lung cancer cells, are resistant to schweinfurthin treatment up to micromolar concentrations. At this time, the precise mechanism of action and target for these compounds is unknown. Here, we employ RNA sequencing of cells treated with 50 nM schweinfurthin analog TTI-3066 for 6 and 24 h to elucidate potential mechanisms and pathways which may contribute to schweinfurthin sensitivity and resistance. The data was analyzed via an interaction model to observe differential behaviors between sensitive SF-295 and resistant A549 cell lines. We show that metabolic and stress-response pathways were differentially regulated in the sensitive SF-295 cell line as compared with the resistant A549 cell line. In contrast, A549 cell had significant alterations in response genes involved in translation and protein metabolism. Overall, there was a significant interaction effect for translational proteins, RNA metabolism, protein metabolism, and metabolic genes. Members of the Hedgehog pathway were differentially regulated in the resistant A549 cell line at both early and late time points, suggesting a potential mechanism of resistance. Indeed, when cotreated with the Smoothened inhibitor cyclopamine, A549 cells became more sensitive to schweinfurthin treatment. This study therefore identifies a key interplay with the Hedgehog pathway that modulates sensitivity to the schweinfurthin class of compounds.

Cytotoxic diaporindene and tenellone derivatives from the fungus Phomopsis lithocarpus.

Nine new compounds, including five natural rarely-occurring 2, 3-dihydro-1H-indene derivatives named diaporindenes E-I (1-5), and four new benzophenone analogues named tenellones J-M (6-9) were isolated from the deep-sea sediment-derived fungus Phomopsis lithocarpus FS508. All the structures for these new compounds were fully characterized on the basis of spectroscopic data, NMR spectra, and ECD calculation and single-crystal X-ray diffraction analysis. The potential anti-tumor activities of compounds 1-9 against four tumor cell lines SF-268, MCF-7, HepG-2, and A549 were evaluated using the SRB method. Compound 7 exhibited cytotoxic activity against the SF-268 cell line with an IC50 value of 11.36 μmol·L-1.

Structurally Diverse Polycyclic Salicylaldehyde Derivative Enantiomers from a Marine-Derived Fungus Eurotium sp. SCSIO F452.

To enlarge the chemical diversity of Eurotium sp. SCSIO F452, a talented marine-derived fungus, we further investigated its chemical constituents from a large-scale fermentation with modified culture. Four pairs of new salicylaldehyde derivative enantiomers, euroticins F-I (1–4), as well as a known one eurotirumin (5) were isolated and characterized. Compound 1 features an unprecedented constructed 6/6/6/5 tetracyclic structures, while 2 and 3 represent two new types of 6/6/5 scaffolds. Their structures were established by comprehensive spectroscopic analyses, X-ray diffraction, 13C NMR, and electronic circular dichroism calculations. Selected compounds showed significant inhibitory activity against α-glucosidase and moderate cytotoxic activities against SF-268, MCF-7, HepG2, and A549 cell lines.

Novel thienopyrimidine-aminothiazole hybrids: Design, synthesis, antimicrobial screening, anticancer activity, effects on cell cycle profile, caspase-3 mediated apoptosis and VEGFR-2 inhibition

A series of novel hybrid compounds of hexahydrobenzo[4,5]thieno[2,3-d]pyrimidine with aminothiazole scaffolds were synthesized. The synthesized compounds were evaluated for their cytotoxic activity against the NCI-60 human tumor cell line panel. Compounds 7c, 7d and 7e exhibited significant antiproliferative activities at 10−5 M dose. Compound 7c exhibited excellent cytotoxic activity against CNS cancer cell lines including SNB-75 and SF-295 as well as renal cancer cell line CAKI-1 when compared with sorafenib as standard anticancer drug. In addition, compound 7d showed almost comparable anticancer activity to sorafenib against SNB-75 cell line and displayed moderate activity against SF-295 and CAKI-1 cell lines in comparison to sorafenib. Compound 7c inhibited the vascular endothelial growth factor receptor 2 (VEGFR-2) with IC50 of 62.48 ± 3.7 nM and decreased both total VEGFR-2 and phosphorylated VEGFR-2 in treated SNB-75 cells suggesting its ability to down regulate cell proliferation, growth, and survival.. The flow cytometric analysis showed that 7c displayed its cytotoxic activity through the reduction of the cellular proliferation and induction of cell cycle arrest at the G2/M phase. Compound 7c clearly boosted the level of the apoptotic caspase-3. All the synthesized compounds were also screened for their antibacterial and antifungal activity against four pathogenic strains of both Gram-positive and Gram-negative as well as Candida albicans. Only compound 7d exhibited antifungal activity against Candida albicans compared to nystatin as the standard antifungal compound.

New 5-carba-pterocarpans: Synthesis and preliminary antiproliferative activity on a panel of human cancer cells

Natural pterocarpans and synthetic 5-carba-pterocarpans are isosteres in which the oxygen atom at position 5 in the pyran-ring of pterocarpans is replaced by a methylene group. These 5-carba-analogues were obtained in good yields through the palladium-catalyzed oxyarylation of alcoxy-1,2-dihydronaphthalens with o-iodophenols in PEG-400. They were evaluated on human cancer cell lineages derived respectively from prostate tumor (PC3, IC50 = 11.84 μmol L−1, SI > 12)) and acute myeloid leukemia (HL-60, IC50 = 8.81 μmol L−1, SI > 16), highly incident cancer types presenting resistance against traditional chemotherapeutics. Compound 6c (LQB-492) was the most potent (IC50 = 3.85 μmol L−1, SI > 37) in SF-295 cell lineage (glioblastoma). Such findings suggest that 5-carba-pterocarpan can potentially be new hit compounds for further development of novel antiproliferative agents.