Standard Cytotoxic Drugs Research Articles

Capparis cartilaginea Decne. as a natural source of antioxidant, anti-inflammatory, and anti-cancer herbal drug

BackgroundCapparis cartilaginea Decne.(C. cartilaginea Decne.) a medicinally important plant that belongs to the family Capparaceae. Traditionally the fruit, leaf, and root have been believed to show anti-inflammatory effects and can also be used as agents. PurposeThe objective of this study is to investigate the chemical compositions, in-vitro antioxidant, anti-cancer and anti-inflammatory activities of the ethanolic extract of Capparis cartilaginea Decne. leaves. Study methodsThe chemical compounds were investigated by Gas Chromatography–Mass Spectrometry (GC–MS) analysis. Ferric-bipyridine reducing capacity of total antioxidants (FBRC), Ferric reducing antioxidant power (FRAP) were utilized to determine antioxidant activity. The cytotoxic activity was evaluated using a 3-[4,5-dimethylthiazole- 2-yl]-2,5-diphenyl tetrazolium bromide (MTT) assay. Additionally, in vitro anti-inflammatory activity of the ethanolic extract of C. cartilaginea Decne. leaves using COX1 and protein denaturation methods. ResultsThe major twenty- four bioactive compounds from fifty compounds were identified including alkaloids, flavonoids, phenols, fatty acids, and carotenes. Pleiocarpamine was the major constituent of the extract (73.07 %). Additionally, in vitro anti-inflammatory activity of the ethanolic extract of C. cartilaginea Decne. leaves using COX1 and protein denaturation methods showed a strong effect with IC50 values of 60.23 and 17.67 µg/mL respectively, compared to Indomethacin and Diclofenac as a standard anti-inflammatory drug.; while FBRC and FRAP were utilized to determine antioxidant activity slowed high antioxidants capacity with values 0.056 ± 0.001and 0.03 ± 0.00196 Ascorbic acid equivalent/g of extract (AAE) and DPPH radical scavenging method show IC50 value 10 ± 1 %. Evaluation of the cytotoxic activity against three human cancer cell lines colon carcinoma cells HCT-116, Breast carcinoma cells MCF-7, and human muscle Rhabdomyosarcoma RD cell line using MTT assay showed a significant effect with IC50 values 59.58 ± 1.5, 39.14 ± 3.09, and 102 ± 8.75 µg/mL, compared to Vinblastine Sulfate as a standard cytotoxic drug. Yemeni C. cartilaginea Decne. showed a higher effect on MCF-7 compared to Iranian C. cartilaginea Decne. as well as established a higher antioxidant activity than that extracts obtained from Jordan. ConclusionEthanolic leaves extract of C. cartilaginea Decne. have the potential for development as therapeutic agents for cytotoxicity on certain cancer cells following further investigation. C. cartilaginea Decne. leaves that could have medicinal values and application in industries, were used to design the drug for the treatment of various types of inflammatory diseases.

Insights on the Dynamic Innovative Tumor Targeted-Nanoparticles-Based Drug Delivery Systems Activation Techniques.

Anti-cancer conventional chemotherapeutic drugs novel formula progress, nowadays, uses nano technology for targeted drug delivery, specifically tailored to overcome therapeutic agents' delivery challenges. Polymer drug delivery systems (DDS) play a crucial role in minimizing off-target side effects arising when using standard cytotoxic drugs. Using nano-formula for targeted localized action, permits using larger effective cytotoxic doses on a single special spot, that can seriously cause harm if it was administered systemically. Therefore, various nanoparticles (NPs) specifically have attached groups for targeting capabilities, not seen in bulk materials, which then need activation. In this review, we will present a simple innovative, illustrative, in a cartoon-way, enumeration of NP anti-cancer drug targeting delivery system activation-types. Area(s) covered in this review are the mechanisms of various NP activation techniques.

Exvivo assessment of cancer drug sensitivity in epithelial ovarian cancer and its association with histopathological type, treatment history and clinical outcome.

Epithelial ovarian cancer (EOC) is divided into type I and type II based on histopathological features. Type I is clinically more indolent, but also less sensitive to chemotherapy, compared with type II. The basis for this difference is not fully clarified. The present study investigated the pattern of drug activity in type I and type II EOC for standard cytotoxic drugs and recently introduced tyrosine kinase inhibitors (TKIs), and assessed the association with treatment history and clinical outcome. Isolated EOC tumor cells obtained at surgery were investigated for their sensitivity to seven standard cytotoxic drugs and nine TKIs using a short-term fluorescent microculture cytotoxicity assay (FMCA). Drug activity was compared with respect to EOC subtype, preoperative chemotherapy, cross-resistance and association with progression-free survival (PFS). Out of 128 EOC samples, 120 samples, including 21 type I and 99 type II, were successfully analyzed using FMCA. Patients with EOC type I had a significantly longer PFS time than patients with EOC type II (P=0.01). In line with clinical experience, EOC type I samples were generally more resistant than type II samples to both standard cytotoxic drugs and the TKIs, reaching statistical significance for cisplatin (P=0.03) and dasatinib (P=0.002). A similar pattern was noted in samples from patients treated with chemotherapy prior to surgery compared with treatment-naive samples, reaching statistical significance for fluorouracil, irinotecan, dasatinib and nintedanib (all P<0.05). PFS time gradually shortened with increasing degree of drug resistance. Cross-resistance between drugs was in most cases statistically significant yet moderate in degree (r<0.5). The clinically observed relative drug resistance of EOC type I, as well as in patients previously treated, is at least partly due to mechanisms in the tumor cells. These mechanisms seemingly also encompass kinase inhibitors. Ex vivo assessment of drug activity is suggested to have a role in the optimization of drug therapy in EOC.

Diaporine Potentiates the Anticancer Effects of Oxaliplatin and Doxorubicin on Liver Cancer Cells.

Recent studies have shown that diaporine, a novel fungal metabolic product, has a strong in vitro and in vivo anticancer effect on human non-small-cell lung and breast cancers. In this study, three human hepatocarcinoma cell lines (HepG2, Hep3B, and Huh7) were used to evaluate the efficacy of diaporine alone and in combination with the standard cytotoxic drugs oxaliplatin and doxorubicin for the treatment of liver cancer. We demonstrated that diaporine, oxaliplatin, and doxorubicin triggered a concentration- and time-dependent decrease in the number of HepG2 cells. Diaporine at a concentration of 2.5 μM showed almost 100% inhibition of cell counts at 72 h. Similar effects were observed only with much higher concentrations (100 μM) of oxaliplatin or doxorubicin. Decreases in cell numbers after 48 h treatment with diaporine, oxaliplatin, and doxorubicin were also demonstrated in two additional hepatoma cell lines, Hep3B and Huh7. The combination of these drugs at low concentration for 48 h in vitro noticeably showed that diaporine improved the inhibitory effect on the number of cancer cells induced by oxaliplatin or doxorubicin. Additionally, this combination effectively inhibited colony growth in vitro. We found that inhibition of phosphorylation of ERK1/2 significantly increased when diaporine was used in combination with other agents. In addition, we also found that when diaporine was used in combination with doxorubicin or oxaliplatin, their proapoptotic effect greatly increased. We further revealed that the induction of apoptosis in hepatoma cells after treatment is due, at least in part, to the inhibition of phosphorylation of AKT, leading to the activation of caspase-3, inactivation of poly (ADP-ribose) polymerase (PARP), and subsequently to DNA damage, as indicated by the increased level of H2AX. Based on these findings, we suggest that diaporine in combination with the standard cytotoxic drugs oxaliplatin and doxorubicin may play a role in the treatment of liver cancer.

A phenylpropanoid dimer from the leaves of Piper betle

Phytochemical analyses of the chloroform extract of Piper betle L. var. Sanchi, Piperaceae, leaves led to the isolation of a new phenylpropanoid analogue for the first time: hydroxychavicol dimer, 2-(γ'-hydroxychavicol)-hydroxychavicol (S1), on the basis of spectroscopic data 1 D (1H and 13C) and 2 D (1H–1H COSY and HMBC) NMR, as well as ESI-MS, FT-IR, HR-ESI-MS and LC-ESI-MS. Compound S1 exhibited excellent antioxidant DPPH radical scavenging activity with IC50 values of 9.07 μg/mL, compared to ascorbic acid as a standard antioxidant drug with IC50 value of 3.41 μg/mL. Evaluation of cytotoxic activity against two human colon cancer cell lines (HT 29 and COLO-205) showed significant effect with GI50 values of 73.81 and 64.02 μmol/L, compared to Doxorubicin® as a standard cytotoxic drug with GI50 value of <10 μmol/L.

In vitro antiplasmodial activity, cytotoxicity, antioxidant action and GC-FID analysis of Allanblackia floribunda Oliv

This study evaluated the in vitro antiplasmodial efficacy and cytotoxicity of Allanbackia floribunda stem bark extract, leaf extract and oil. It also assessed the phytochemical compositions and antioxidant action of the stem bark fractions as well as the phytochemical fingerprint of the most active fraction (dichloromethane). Trager and Jensen method was used to culture Plasmodium falciparum, Mark III test developed by WHO was used to assess the antiplasmodial activity of the plant’s crude extract and fractions against the ring stage of P. falciparum strain, Pf3D7. Cytotoxicity was determined against Vero cell line using microculture tetrazolium (MTT) test. Gas chromatography with flame ionization detection (GC-FID) was employed to identify phytochemical fingerprint of the most active fraction. The stem bark extract had better antiplasmodial activity (IC50Pf3D7 of 4.3 ± 0.17 μg/mL) compared with the leaf extract (IC50Pf3D7, 8.0 ± 0.28 μg/mL) and oil (IC50Pf3D7 > 100 μg/mL). Both the leaf and stem bark extracts were found to be non-cytotoxic compared with the standard cytotoxic drug, doxorubicin. The selectivity indices (S.I.) of the extracts against the parasite were 20.06 and 8.85 for the stem bark and leaf respectively. Dichloromethane fraction had the highest inhibition against the P. falciparum parasite with IC50Pf3D7 of 1.51 μg/ mL. GC-FID analysis showed high presence antiplasmodial flavonoids and terpenes. This investigation confirmed that A. floribunda stem bark has potent activity against P. falciparum, and it is relatively safe to normal cell.Article HighlightsAllanblackia floribunda methanol stem bark and leaf extracts could inhibit the growth of chloroquine sensitive Plasmodium falciparum (Pf3D7) in vitro.The stem bark infusion of Allanblackia floribunda was found to be nontoxic and safe at moderate doses to normal cell line (Vero cell line).Dichloromethane fraction of the stem bark showed excellent inhibition against chloroquine sensitive malaria parasite.

Drugging DNA Repair to Target T-ALL Cells

Despite recent progress in treatment, prognostication for T-cell acute lymphoblastic leukemia (T-ALL) patients, including those with early T-cell precursor ALL (ETP-ALL) is rather poor. Therefore, new therapies are needed to extend the complete remission time/cure and/or to treat refractory T-ALL patients. T-ALL cells accumulate potentially lethal “spontaneous” and drug-induced DNA double-strand breaks (DSBs). Thus, T-ALL cells may be “addicted” to DSB repair mechanisms to survive and targeting these pathways should sensitize them to lethal effect of DSBs. In proliferating cells DSBs are usually repaired by homologous recombination (HR) repair. HR works predominantly on broken replication forks and usually depends on BRCA1, BRCA2, PALB2, RAD51 paralogs (RAD51B, RAD51C, RAD51D, XRCC2, and XRCC3), and RAD51 (BRCA pathway). However, in BRCA deficient cells displaying low expression of at least one of the proteins from the pathway, PARP1-LIG3 -mediated alternative non-homologous end-joining (Alt-NHEJ) and/or RAD52-RAD51-dependent alternative HR mechanism protect cells from lethal effect of DSBs. Therefore, PARP1 and/or RAD52 are attractive targets to eliminate BRCA-deficient leukemia cells. Although inactivating mutations in genes involved in HR are extremely rare in T-ALL, we show here that microarray gene expression profiling of T-ALLs displayed wide range of expression of mRNAs encoding the proteins in BRCA pathway suggesting that numerous leukemias from individual patients were BRCA deficient. In particular, lower expression of BRCA genes (BRCA1, BRCA2, XRCC2, RAD51B, RAD51C, RAD51) have been detected in ETP-ALLs. These data implicate malfunctioning BRCA pathway in a cohort of T-ALLs, especially in ETP-ALLs. Conversely, an average expression of PARP1 and LIG3 mRNAs seemed not to be affected, and RAD52 mRNA was even overexpressed in ETP-ALLs when compared to T-ALLs. Next, we tested the sensitivity of primary leukemia xenograft (PLX) CD3+ cells from T-ALL/ETP-ALL patients and of normal T cells to DNA repair inhibitors. All 3 samples of ETP-ALL cells were more sensitive to PARP1 inhibitor olaparib and RAD52 inhibitor 6(OH)-DL-dopa when compared to normal pan-T cells. T-ALL PLXs displayed differences in sensitivity to PARP1 and RAD52 inhibitors; two samples appeared sensitive whereas three seemed resistant. In addition, cytotoxic drug Ara-C combined with PARP1 or RAD52 inhibitors exerted stronger anti-leukemia activity when compared to individual treatments in PARP1/RAD52 inhibitor-sensitive leukemia cells. To determine if the differences in sensitivity to PARP1 and RAD52 inhibitors were associated with deficiencies in HR activity, sensitive and resistant leukemia cells as well as normal pan-T cells were transfected with the plasmid containing HR reporter cassette. HR activity was determined by restoration of a functional GFP gene and detection of GFP+ cells. T-ALL/ETP-ALL cells which were sensitive to PARP1 and RAD52 inhibitors displayed diminished HR activity in comparison to normal pan-T cells and T-ALL cells resistant to the inhibitors. Moreover, BRCA1 and RAD51 nuclear foci formation was inhibited in leukemia cells which displayed reduced HR activity and increased sensitivity to PARP1 and RAD52 inhibitors. In summary, our results suggest that majority of ETP-ALLs and a subset of T-ALLs display “BRCAness” phenotype, which predisposes them to be sensitive to PARP1 and RAD52 inhibitors. While RAD52 inhibitors await clinical development, PARP1 inhibitors such as Lynparza (olaparib), Rubraca (rucaparib) and Zeluja (niraparib) have been FDA approved to treat breast and/or ovarian cancers carrying BRCA1/2 mutations. We postulate that these inhibitors may be used to improve therapeutic effect of standard cytotoxic drugs in pre-selected patients with “BRCAness” T-ALLs/ETP-ALLs. DisclosuresMullighan:Loxo Oncology: Research Funding; Amgen: Consultancy.

Targeting P53 as a Future Strategy to Overcome Gemcitabine Resistance in Biliary Tract Cancers.

Gemcitabine-based chemotherapy is the current standard treatment for biliary tract cancers (BTCs) and resistance to gemcitabine remains the clinical challenge. TP53 mutation has been shown to be associated with poor clinicopathologic characteristics and survival in patients with BTCs, indicating that p53 plays an important role in the treatment of these cancers. Herein, we comprehensively reviewed previous BTC preclinical research and early clinical trials in terms of p53, as well as novel p53-targeted treatment, alone or in combination with either chemotherapy or other targeted therapies in BTCs. Preclinical studies have demonstrated that p53 mutations in BTCs are associated with enhanced gemcitabine resistance, therefore targeting p53 may be a novel therapeutic strategy for treatment of BTCs. Directly targeting mutant p53 by p53 activators, or indirectly by targeting cell cycle checkpoint proteins (Chk1, ataxia telangiectasia related (ATR), and Wee1) leading to synthetic lethality, may be potential future strategies for gemcitabine-resistant p53 mutated BTCs. In contrast, for wild-type p53 BTCs, activation of p53 by inhibition of its negative regulators (MDM2 and wild-type p53-induced phosphatase 1 (WIP1)) may be alternative options. Combination therapies consisting of standard cytotoxic drugs and novel small molecules targeting p53 and related signaling pathways may be the future key standard approach to beat cancer.

Two new anticancer phenolic derivatives from leaves of Piper betle Linn.

In this study, phytochemical analyses of the chloroform extract of Piper betle L. var. haldia and maghai, Piperaceae, leaves led to the isolation of two new phenolic derivatives: 1-n-decanoyl hydroxy-benzoic acid/1-n-decanoyl phenol (H2) and 3-butylphenol (M1) on the basis of spectroscopic data 1D NMR (1H, 13C) and 2D NMR (1H - 1H COSY, HMBC) as well as ESI-MS, FT-IR and HR-ESI-MS analyses. Compounds H2 and M1 showed excellent antioxidant DPPH free radical scavenging activity with IC50 values of 10.66 μ/mL and 13.65 μg/mL compared to ascorbic acid as a standard antioxidant with an IC50 value of 2.52 μg/mL. Evaluation of cytotoxic activity against two human oral cancer cell lines (SCC-40 and SCC-29B) showed significant effect with GI50 values of 24.08 and 33.08 μg/mL for compound H2 and 35.03 and 47.06 μg/mL for compound M1, compared to Doxorubicin® as a standard cytotoxic drug with GI50 value of < 10 μg/mL.

Cytotoxic effect of acetogenins and sesquiterpenes obtained from the Red alga &lt;i&gt;Laurencia majuscula&lt;/i&gt;

Purpose: To evaluate the cytotoxicity of n-hexane extract and its metabolites obtained from the red alga, Laurencia majuscula, against three cancer cell lines HCT-116 (colon cancer), PC-3 (prostate cancer) and HepG2 (liver cancer) cells; and to identify the phytochemical compound(s) involved.&#x0D; Methods: Solvent extraction, thin layer chromatography, aluminum oxide column chromatography, and preparative thin layer chromatography (PTLC) were employed for isolating pure compounds from nhexane extract of Laurencia majuscula. Nuclear magnetic resonance (NMR) and mass spectrometry (MS) measurements were used for structural elucidation of the compounds. The cytotoxicity of the nonpolar extract and isolated compounds were evaluated against HCT, PC-3, and HepG2 cells using MTT assay, relative to the standard cytotoxic drug (cisplatin).&#x0D; Results: Three sesquiterpenes (1, 2 and 8), and five acetogenins (3-7) were isolated from the n-hexane extract. The n-hexane extract showed higher potent cytotoxic effect than sesquiterpenes and the acetogenins (3-7).&#x0D; Conclusion: These results indicate that the n-hexane extract of Laurencia majuscula exerts significant cytotoxicity against HCT-116, PC-3 and HepG2 cell lines, thus suggesting that the plant extract may be effective chemotherapeutic agents for the management of colon, postrate and liver cancer.&#x0D; Keywords: Red Sea alga, Rhodomelaceae, Polyketides, Terpenes, Anticancer

REPRODUCTIVE FUNCTION AND ANTITUMOR ACTIVITY: DIFFERENT ROLES FOR THE HYPOTHALAMIC HORMONE GnRH

The decapeptide GnRH (Gonadotropin-Releasing Hormone), whose amino acidic sequence was discovered by Dr. A.V. Schally, was initially identified as the key hypothalamic hormone involved in the control of reproductive functions. GnRH, by binding to specific receptors (GnRH-R) at the pituitary level, stimulates the synthesis and secretion of the two gonadotropins (LH, luteinizing hormone and FSH, follicle stimulating hormone) and the downstream production of steroid hormones at the gonadal level. At present, these receptors represent the molecular targets of the standard pharmacological treatments for hormone-related tumors, such as androgen-dependent prostate cancer. Actually, chronic administration of synthetic GnRH agonists induces the desensitization of pituitary receptors and, subsequently, the suppression of testicular androgen production. The physiological role of GnRH in reproductive functions, and its regulation, represented a very important line of research for professor Martini and His colleagues. In the last three decades it has become increasingly clear that GnRH-R are expressed also in a wide range of tumors, both related and unrelated to the reproductive system; in particular GnRH-R are expressed in prostate cancers after development of resistance to androgen ablation therapy (castration resistant prostate cancer, CRPC), a tumor known to be refractory to standard chemotherapy. Activation of these receptors by means of GnRH agonists is associated with a significant antiproliferative/antimetastatic/antiangiogenic activity. These different biological effects at pituitary vs. prostate tissues are related to specific intracellular signal transduction pathways. Based on these observations, tumor GnRH-R are presently considered an effective molecular target for novel therapies (‘targeted’ therapies). In particular, GnRH-based bioconjugates, in which a standard cytotoxic drug is linked to a GnRH analog, have been developed. The rationale for this ‘targeted’ therapy is that the GnRH analog behaves as the targeting moiety by binding to GnRH-R in tumors, thus specifically delivering (targeting) the cytotoxic drug to tumor cells. At the level of tumor cells, the bioconjugate is internalized and degraded at the lysosomal level; in this way the anticancer drug is specifically released into the tumor cells to exert its cytotoxic effects, while sparing normal cells. In conclusion, GnRH-R are expressed not only at the pituitary level but also in a wide range of tumor tissues; these receptors are at present under investigation as an effective molecular target for the development of novel therapeutic strategies.

PTC-209 Anti-Cancer Effects Involved the Inhibition of STAT3 Phosphorylation.

Introduction: Lung, breast, and colorectal cancers are the leading causes of cancer-related deaths despite many therapeutic options, including targeted therapy and immunotherapies. Methods: Here, we investigated the impact of PTC-209, a small-molecule Bmi-1 inhibitor, on human cancer cell viability alone and in combination with anticancer drugs, namely, cisplatin, oxaliplatin, 5-fluorouracil, camptothecin, and Frondoside-A and its impact on cellular migration and colony growth in vitro and on tumor growth in ovo. Results: We demonstrate that PTC-209 causes a concentration- and time-dependent decrease in the cellular viability of lung cancer cells (LNM35 and A549), breast cancer cells (MDA-MB-231 and T47D), and colon cancer cells (HT-29, HCT8/S11, and HCT-116). Similarly, treatment with PTC-209 significantly decreased the growth of LNM35, A549, MDA-MB-231, and HT-29 clones and colonies in vitro and LNM35 and A549 tumor growth in the in ovo tumor xenograft model. PTC-209 at the non-toxic concentrations significantly reduced the migration of lung (LNM35 and A549) and breast (MDA-MB-231) cancer cells. Moreover, we show that PTC-209, at a concentration of 1 μM, enhances the anti-cancer effects of Frondoside-A in lung, breast, and colon cancer cells, as well as the effect camptothecin in breast cancer cells and the effect of cisplatin in lung cancer cells in vitro. However, PTC-209 failed to enhance the anti-cancer effects of oxaliplatin and 5-fluorouracil in colon cancer cells. Treatment of lung, breast, and colon cancer cells with PTC-209 (1 and 2.5 μM) for 48 h showed no caspase-3 activation, but a decrease in the cell number below the seeding level suggests that PTC-209 reduces cellular viability probably through inhibition of cell proliferation and induction of cell death via a caspase-3–independent mechanism. Molecular mechanism analysis revealed that PTC-209 significantly inhibited the STAT3 phosphorylation by decreasing the expression level of gp130 as early as 30 min post-treatment. Conclusion: Our findings identify PTC-209 as a promising anticancer agent for the treatment of solid tumors either alone and/or in combination with the standard cytotoxic drugs cisplatin and camptothecin and the natural product Frondoside-A.

Evidence to date: talazoparib in the treatment of breast cancer.

Approximately 5–10% of all patients diagnosed with breast cancer have germline BRCA1/2 mutations, which make their disease more susceptible to DNA-damaging agents and a new class of drugs known as poly(ADP-ribose) polymerase (PARP) inhibitors. Talazoparib is a new PARP inhibitor that has been recently approved for use in patients with metastatic breast cancer with germline BRCA mutations after a phase III trial showed superior progression-free survival when compared to standard chemotherapy. In this review, we analyze the development of talazoparib as well as its safety profile and the potential role of the combination therapy with standard cytotoxic drugs and with novel therapies.

MiR-183-5p Inhibits Occurrence and Progression of Acute Myeloid Leukemia via Targeting Erbin.

Erbin has been shown to have significant effects on the development of solid tumors. However, little is known about its function and regulatory mechanism in hematological malignancies. The biological function of Erbin on cell proliferation was measured in vitro and in vivo. The predicted target of Erbin was validated by dual-luciferase reporter assay and rescue experiment. We found that overexpression of Erbin could inhibit the cell proliferation and promote the cell differentiation of acute myeloid leukemia (AML) cells, whereas depletion of Erbin could enhance the cell proliferation and block the cell differentiation in AML cells in vitro and in vivo. Besides, miR-183-5p was identified as the upstream regulator that negatively regulated the Erbin expression. The results were confirmed by dual-luciferase reporter and RNA pull-down assay. Furthermore, we found that miR-183-5p negatively regulated Erbin, resulting in enhanced cell proliferation of AML cells via activation of RAS/RAF/MEK/ERK and PI3K/AKT/FoxO3a pathways. The activation of RAS/RAF/MEK/ERK and PI3K/AKT/FoxO3a pathways was mediated by Erbin interacting with Grb2. These results were also validated by rescue experiments in vitro and in vivo. All above-mentioned findings indicated that the miR-183-5p/Erbin signaling pathway might represent a novel prognostic biomarker or therapeutic target for treatment of AML.

Diclofenac 1,3,4-Oxadiazole Derivatives; Biology-Oriented Drug Synthesis (BIODS) in Search of Better Non-Steroidal, Non-Acid Antiinflammatory Agents.

Inflammation is defined as the response of immune system cells to damaged or injured tissues. The major symptoms of inflammation include increased blood flow, cellular influx, edema, elevated cellular metabolism, reactive oxygen species (ROS) nitric oxide (NO) and vasodilation. This normally protective mechanism against harmful agents when this normal mechanism becomes dysregulated that can cause serious illnesses including ulcerative colitis, Crohn's disease, rheumatoid arthritis, osteoarthritis, sepsis, and chronic pulmonary inflammation. In this study synthetic transformations on diclofenac were carried out in search of better non-steroidal antiinflammatory drugs (NSAIDs), non-acidic, antiinflammatory agents. For this purpose diclofenac derivatives (2-20) were synthesized from diclofenac (1). All derivatives (2-20) and parent diclofenac (1) were evaluated for their antiinflammatory effect using different parameters including suppression of intracellular reactive oxygen species (ROS), produced by whole blood phagocytes, produced by neutrophils, and inhibition of nitric oxide (NO) production from J774.2 macrophages. The most active compound also evaluated for cytotoxicity activity. Diclofenac (1) inhibited the ROS with an IC50 of 3.9 ± 2.8, 1.2 ± 0.0 µg/mL respectively and inhibited NO with an IC50 of 30.01 ± 0.01 µg/mL. Among its derivatives 4, 5, 11, 16, and 20, showed better antiinflammatory potential. The compound 5 was found to be the most potent inhibitor of intracellular ROS as well as NO with IC50 values of 1.9 ± 0.9, 1.7 ± 0.4 µg/mL respectively and 7.13 ± 1.0 µg/mL, respectively, and showed good inhibitory activity than parent diclofenac. The most active compounds were tested for their toxic effect on NIH-3T3 cells where all compounds were found to be non-toxic compared to the standard cytotoxic drug cyclohexamide. Five derivatives were found to be active. Compound 5 was found to be the most potent inhibitor of ROS and NO compared to parent diclofenac 1 and standard drugs ibuprofen and L-NMMA, respectively. The most active compounds 1, 4, 5, 11 and 20 were found to be non-toxic on NIH-3T3 cells. Compound 4, 5, and 20 also showed good antiinflammatory potential, compound 11 and 16 showed moderate and low level of inhibition, respectively.

Combining BH3-mimetics to target both BCL-2 and MCL1 has potent activity in pre-clinical models of acute myeloid leukemia

Improving outcomes in acute myeloid leukemia (AML) remains a major clinical challenge. Overexpression of pro-survival BCL-2 family members rendering transformed cells resistant to cytotoxic drugs is a common theme in cancer. Targeting BCL-2 with the BH3-mimetic venetoclax is active in AML when combined with low-dose chemotherapy or hypomethylating agents. We now report the pre-clinical anti-leukemic efficacy of a novel BCL-2 inhibitor S55746, which demonstrates synergistic pro-apoptotic activity in combination with the MCL1 inhibitor S63845. Activity of the combination was caspase and BAX/BAK dependent, superior to combination with standard cytotoxic AML drugs and active against a broad spectrum of poor risk genotypes, including primary samples from patients with chemoresistant AML. Co-targeting BCL-2 and MCL1 was more effective against leukemic, compared to normal hematopoietic progenitors, suggesting a therapeutic window of activity. Finally, S55746 combined with S63845 prolonged survival in xenograft models of AML and suppressed patient-derived leukemia but not normal hematopoietic cells in bone marrow of engrafted mice. In conclusion, a dual BH3-mimetic approach is feasible, highly synergistic, and active in diverse models of human AML. This approach has strong clinical potential to rapidly suppress leukemia, with reduced toxicity to normal hematopoietic precursors compared to chemotherapy.

The new ether derivative of phenylpropanoid and bioactivity was investigated from the leaves of Piper betle L.

A new ether derivative of phenylpropanoid compound, γ-(γ′-isohydroxychavicol)-chavicol octanyl ether (K1) along with one known phenylpropanoid named allyl-pyrocatechol or hydroxychavicol (2) were isolated from Piper betle var. kali collected from Tumluk district, West Bengal India. We first report the presence of compound K1 in the genus Piper. Their structures were established on the basis of various spectroscopic analyses. Compounds K1 and 2 showed excellent antioxidant DPPH free radical scavenging activity with IC50 values of 4.61 and 4.12 µg/mL compared to ascorbic acid as a standard antioxidant drug with IC50 value of 3.42 µg/mL, respectively. Evaluation of in vitro cytotoxic activities of compounds K1 and 2 showed significant effects against human oral cancer cell lines (AW13516 and AW8507), human hepatoma cell lines (HEPG2 and PLC-PRF-5) and a human pancreatic cell line (MIA-PA-CA-2), compared to Doxorubicin® as a standard cytotoxic drug with GI50 values of <10 and 18.18 µg/mL.

Frondoside A Enhances the Anti-Cancer Effects of Oxaliplatin and 5-Fluorouracil on Colon Cancer Cells.

Over recent years, we have demonstrated that Frondoside A, a triterpenoid glycoside isolated from an Atlantic sea cucumber, has potent in vitro and in vivo anti-cancer effects against human pancreatic, breast, and lung cancer. We have also demonstrated that Frondoside A is able to potentiate and/or synergize the anti-cancer effects of major classical cytotoxic agents, namely, gemcitabine, paclitaxel, and cisplatin, in the treatment of pancreatic, breast, and lung cancer, respectively. This study evaluates the impact of Frondoside A alone and in combination with the standard cytotoxic drugs oxaliplatin and 5-fluorouracil (5-FU) in the treatment of colon cancer using three human colon cancer cell lines, namely, HT-29, HCT-116, and HCT8/S11. We demonstrate that Frondoside A, oxaliplatin, and 5-FU cause a concentration- and time-dependent reduction in the number of HT-29 colon cancer cells. A concentration of 2.5 µM of Frondoside A led to almost 100% inhibition of cell numbers at 72 h. A similar effect was only observed with a much higher concentration (100 µM) of oxaliplatin or 5-FU. The reduction in cell numbers by Frondoside A, oxaliplatin, and 5-FU was also confirmed in two other colon cancer cell lines, namely, HCT8/S11 and HCT-116, treated for 48 h. The combinations of low concentrations of these drugs for 48 h in vitro clearly demonstrated that Frondoside A enhances the inhibition of cell numbers induced by oxaliplatin or 5-FU. Similarly, such a combination also efficiently inhibited colony growth in vitro. Interestingly, we found that the inhibition of ERK1/2 phosphorylation was significantly enhanced when Frondoside A was used in combination treatments. Moreover, we show that Frondoside A and 5-FU, when used alone, induce a concentration-dependent induction of apoptosis and that their pro-apoptotic effect is dramatically enhanced when used in combination. We further demonstrate that apoptosis induction upon the treatment of colon cancer cells was at least in part a result of the inhibition of phosphorylation of the survival kinase AKT, leading to caspase-3 activation, poly (ADP-ribose) polymerase (PARP) inactivation, and consequently DNA damage, as suggested by the increase in the level of γH2AX. In light of these findings, we strongly suggest that Frondoside A may have a role in colon cancer therapy when used in combination with the standard cytotoxic drugs oxaliplatin and 5-FU.

New chemical constituents from the Piper betle Linn. (Piperaceae)

The phytochemical investigation of chloroform extract from Piper betle var. haldia, Piperaceae, leaves has resulted in the isolation of two new chemical constituents which were identified as 1-n-dodecanyloxy resorcinol (H1) and desmethylenesqualenyl deoxy-cepharadione-A (H4), on the basis of spectroscopic data 1D NMR (1H and 13C) and 2D NMR (1H-1H COSY and HMBC) as well as ESI-MS, FT-IR and HR-ESI-MS analyses. Compounds H1 and H4 showed excellent antioxidant DPPH free radical scavenging activity with IC50 values of 7.14 μg/mL and 8.08 μg/mL compared to ascorbic acid as a standard antioxidant drug with IC50 value of 2.52 μg/mL, respectively. Evaluation of cytotoxic activity against human hepatoma cell line (PLC-PRF-5) showed moderate effect with the GI50 values of 35.12 μg/mL for H1, 31.01 μg/mL for H4, compared to Doxorubicin® as a standard cytotoxic drug with GI50 value of 18.80 μg/mL.

Enhancing venetoclax activity in acute myeloid leukemia by co-targeting MCL1.

Targeted therapies are frequently combined with standard cytotoxic drugs to enhance clinical response. Targeting the B-cell lymphoma 2 (BCL-2) family of proteins is an attractive option to combat chemoresistance in leukemia. Preclinical and clinical studies indicate modest single-agent activity with selective BCL-2 inhibitors (for example, venetoclax). We show that venetoclax synergizes with cytarabine and idarubicin to increase antileukemic efficacy in a TP53-dependent manner. Although TP53 deficiency impaired sensitivity to combined venetoclax and chemotherapy, higher-dose idarubicin was able to suppress MCL1 and induce cell death independently of TP53. Consistent with an MCL1-specific effect, cell death from high-dose idarubicin was dependent on pro-apoptotic Bak. Combining higher-dose idarubicin with venetoclax was able to partially overcome resistance in Bak-deficient cells. Using inducible vectors and venetoclax to differentially target anti-apoptotic BCL-2 family members, BCL-2 and MCL1 emerged as critical and complementary proteins regulating cell survival in acute myeloid leukemia. Dual targeting of BCL-2 and MCL1, but not either alone, prolonged survival of leukemia-bearing mice. In conclusion, our findings support the further investigation of venetoclax in combination with standard chemotherapy, including intensified doses of idarubicin. Venetoclax should also be investigated in combination with direct inhibitors of MCL1 as a chemotherapy-free approach in the future.