Venkat Pallela - Academia.edu (original) (raw)
Papers by Venkat Pallela
A240 Cytokines mediate hematopoietic cell growth and differentiation via the JAK-STAT pathway and... more A240 Cytokines mediate hematopoietic cell growth and differentiation via the JAK-STAT pathway and aberrations in this pathway have been found to result in leukemogenesis. Thus, point mutations in the JAK2 kinase have been shown to be the causative molecular event in certain myeloproliferative disorders identifying JAK2 as a new molecular target for drug discovery. Here we report the discovery of a new class of kinase inhibitors, α-benzoyl styryl benzyl sulfides, which possess potent kinase inhibitory activity and exhibit cytotoxicity to human tumor cells. One of the compounds that belong to this class, ON 044580 was found to be a potent inhibitor of mutant JAK2 kinase and was non-ATPcompetitive. In vivo, it readily inhibited the proliferation of JAK2V617F-positiveleukemic cells and blocked the phosphorylation of JAK2 and STAT5. Interestingly, this compound was also found to inhibit the kinase activity of both wild type and imatinib resistant (T315I) forms of the BCR-ABL kinase, whic...
Journal of Clinical Oncology
Oncotarget
Overexpression and constitutive activation of CYCLIN D1 and Casein Kinase 2 are common features o... more Overexpression and constitutive activation of CYCLIN D1 and Casein Kinase 2 are common features of many hematologic malignancies, including mantle cell lymphoma (MCL) and leukemias such as T-cell acute lymphoblastic leukemia (T-ALL). Although both CK2 and CDK4 inhibitors have shown promising results against these tumor types, none of these agents have achieved objective responses in the clinic as monotherapies. Because both proteins play key roles in these and other hematological malignancies, we have analyzed the therapeutic potential of ON108110, a novel dual specificity ATP-competitive inhibitor of protein kinase CK2 as well as CDK4/6 in MCL and TALL. We show that in cell growth inhibition assays, MCL and TALL cell lines exhibited increased sensitivity to ON108110 when compared to other tumor types. Treatment with ON108110 reduced the level of phosphorylated RB-family proteins. In addition, ON108110 treatment resulted in concentration dependent inhibition of PTEN phosphorylation and a concomitant decrease in PI3K-AKT signaling mediated by CK2. Accordingly, cells treated with ON108110 rapidly accumulated in the G 0 /G 1 stage of the cell cycle as a function of increasing concentration followed by rapid onset of apoptosis. Together, these results indicate that dual inhibition of CK2 and CDK4/6 may be an efficient treatment of MCL and T-ALLs displaying upregulation of CK2/PI3K and CDK4 signaling pathways.
Journal of Pharmaceutical and Biomedical Analysis, Mar 5, 2013
ON 013100, (E)-2,4,6-trimethoxystyryl-3-hydroxy-4-methoxybenzyl sulfone, is a potent kinase inhib... more ON 013100, (E)-2,4,6-trimethoxystyryl-3-hydroxy-4-methoxybenzyl sulfone, is a potent kinase inhibitor whose phosphate form is in Phase I clinical trials in lymphoma and acute lymphoid leukemia. The objectives were to: (a) investigate the possible presence of the glucuronide metabolite of the drug in two representative colon cancer cell lines, a drug resistant (colo-205) and a drug sensitive (colo-320); (b) quantify the glucuronide metabolite and the unchanged drug in the cells after treatment with ON 013100. The glucuronide was synthesized and a selective LC/MS/MS method was developed and validated for the characterization and quantification of the metabolite. The glucuronide metabolite (570.6 Da) was found in the drug-resistant cells upon a 1h incubation with ON 013100 (20 μg/ml). After treatment with the drug, the concentration of the metabolite gradually decreased from 0.84 μg/ml at 0 h through 0.21 μg/ml at 6h to below detection limit of 8.0 ng/ml at 9 h. No glucuronide metabolite was detected in the drug-sensitive cells. The concentrations of intact ON 013100 in the drug-resistant cells gradually decreased from 0.41 μg/ml (0 h) to 0.06 μg/ml (9 h). The corresponding concentrations of the intact drug in the drug-sensitive cells were from 2.88 μg/ml to 0.94 μg/ml.
Synthesis Stuttgart, 2005
Bioorganic & Medicinal Chemistry, 2015
Several families of protein kinases have been shown to play a critical role in the regulation of ... more Several families of protein kinases have been shown to play a critical role in the regulation of cell cycle progression, particularly progression through mitosis. These kinase families include the Aurora kinases, the Mps1 gene product and the Polo Like family of protein kinases (PLKs). The PLK family consists of five members and of these, the role of PLK1 in human cancer is well documented. PLK2 (SNK), which is highly homologous to PLK1, has been shown to play a critical role in centriole duplication and is also believed to play a regulatory role in the survival pathway by physically stabilizing the TSC1/2 complex in tumor cells under hypoxic conditions. As a part of our research program, we have developed a library of novel ATP mimetic chemotypes that are cytotoxic against a panel of cancer cell lines. We show that one of these chemotypes, the 6-arylsulfonyl pyridopyrimidinones, induces apoptosis of human tumor cell lines in nanomolar concentrations. The most potent of these compounds, 7ao, was found to be a highly specific inhibitor of PLK2 when profiled against a panel of 288 wild type, 55 mutant and 12 lipid kinases. Here, we describe the synthesis, structure activity relationship, in vitro kinase specificity and biological activity of the lead compound, 7ao.
Bioorganic & medicinal chemistry
Journal of nuclear medicine : official publication, Society of Nuclear Medicine, 1999
Vasoactive intestinal peptide (VIP) is a naturally occurring 28-amino acid peptide with a wide ra... more Vasoactive intestinal peptide (VIP) is a naturally occurring 28-amino acid peptide with a wide range of biological activities. Recent reports suggest that VIP receptors are expressed on a variety of malignant tumor cells and that the receptor density is higher than for somatostatin. Our aims were to label VIP with 99mTc--a generator-produced, inexpensive radionuclide that possesses ideal characteristics for scintigraphic imaging--and to evaluate 99mTc-VIP for bioactivity and its ability to detect experimental tumors. VIP28 was modified at the carboxy terminus by the addition of four amino acids that provided an N4 configuration for a strong chelation of 99mTc. To eliminate steric hindrance, 4-aminobutyric acid (Aba) was used as a spacer. VIP28 was labeled with 1251, which served as a control. Biological activity of the modified VIP28 agonist (TP3654) was examined in vitro using a cell-binding assay and an opossum internal anal sphincter (IAS) smooth muscle relaxivity assay. Tissue d...
Bioorganic & medicinal chemistry, 2008
A series of 20 novel 1-(4-sulfamylphenyl)-3-trifluoromethyl-5-indolyl pyrazolines were designed, ... more A series of 20 novel 1-(4-sulfamylphenyl)-3-trifluoromethyl-5-indolyl pyrazolines were designed, synthesized, and screened in vitro for anti-inflammatory activity. These compounds were designed for evaluation as dual inhibitors of cyclooxygenases (COX-1 and COX-2) and lipoxygenases (LOX-5, LOX-12, and LOX-15) that are responsible for inflammation and pain. All pyrazoline molecules prepared are optically active and compounds that are more potent in COX-2 inhibitory activity (5a and 5f) were resolved by chiral column and each enantiomer was tested for cyclooxygenase inhibitory activity. Molecular modeling and comparison of molecular models of 5a enantiomers with that of celecoxib model shows that 5a (enantiomer-1) and 5a (enantiomer-2) have more hydrogen bonding interactions in the catalytic domain of COX-2 enzyme than celecoxib. Compounds 5a, 5e, and 5f showed moderate to good LOX-5 and LOX-15 inhibitory activity and this is comparable to that of celecoxib and more potent than rofeco...
Organic & Biomolecular Chemistry, 2013
A stereoselective and efficient method for free radical addition of benzyl thiol to aryl acetylen... more A stereoselective and efficient method for free radical addition of benzyl thiol to aryl acetylene in the presence of Et 3 B-hexane has been developed for the synthesis of (Z) and (E)-styryl benzyl sulfides where base catalyzed hydrothiolations have failed. The scope of this reaction was successfully extended for the synthesis of (E)-ON 01910•Na, a phase III clinical stage anti-cancer agent and its inactive geometrical isomer (Z)-ON 01910•Na. It is interesting to note that all the E-isomers synthesized have shown better cytotoxicity profile on cancer cells compared to the Z-isomers.
Journal of Pharmaceutical and Biomedical Analysis, 2013
ON 013100, (E)-2,4,6-trimethoxystyryl-3-hydroxy-4-methoxybenzyl sulfone, is a potent kinase inhib... more ON 013100, (E)-2,4,6-trimethoxystyryl-3-hydroxy-4-methoxybenzyl sulfone, is a potent kinase inhibitor whose phosphate form is in Phase I clinical trials in lymphoma and acute lymphoid leukemia. The objectives were to: (a) investigate the possible presence of the glucuronide metabolite of the drug in two representative colon cancer cell lines, a drug resistant (colo-205) and a drug sensitive (colo-320); (b) quantify the glucuronide metabolite and the unchanged drug in the cells after treatment with ON 013100. The glucuronide was synthesized and a selective LC/MS/MS method was developed and validated for the characterization and quantification of the metabolite. The glucuronide metabolite (570.6 Da) was found in the drug-resistant cells upon a 1h incubation with ON 013100 (20 μg/ml). After treatment with the drug, the concentration of the metabolite gradually decreased from 0.84 μg/ml at 0 h through 0.21 μg/ml at 6h to below detection limit of 8.0 ng/ml at 9 h. No glucuronide metabolite was detected in the drug-sensitive cells. The concentrations of intact ON 013100 in the drug-resistant cells gradually decreased from 0.41 μg/ml (0 h) to 0.06 μg/ml (9 h). The corresponding concentrations of the intact drug in the drug-sensitive cells were from 2.88 μg/ml to 0.94 μg/ml.
Journal of Medicinal Chemistry, 2008
Journal of Medicinal Chemistry, 2013
Journal of Medicinal Chemistry, 2012
Tubulin, the major structural component of microtubules, is a target for the development of antic... more Tubulin, the major structural component of microtubules, is a target for the development of anticancer agents. A series of (Z)-1-aryl-3-arylamino-2-propen-1-one (10) were synthesized and evaluated for antiproliferative activity in cell-based assay. The most active compound (Z)-1-(2-bromo-3,4,5-trimethoxyphenyl)-3-(3-hydroxy-4-methoxyphenylamino)prop-2-en-1-one (10ae) was tested in 20 tumor cell lines including multidrug resistant phenotype and was found to induce apoptosis in all these cell lines with similar GI(50) values. Flow cytometry studies showed that 10ae arrested the cells in G2/M phase of cell cycle. In addition to G2/M block, these compounds caused microtubule stabilization like paclitaxel and induced apoptosis via activation of the caspase family. The observations made in this investigation demonstrate that (Z)-1-Aryl-3-arylamino-2-propen-1-one (10) represents a new class of microtubule-stabilizing agents.
![Research paper thumbnail of Discovery of 8-Cyclopentyl-2-[4-(4-methyl-piperazin-1-yl)-phenylamino]-7-oxo-7,8-dihydro-pyrido[2,3- d ]pyrimidine-6-carbonitrile ( 7x ) as a Potent Inhibitor of Cyclin-Dependent Kinase 4 (CDK4) and AMPK-Related Kinase 5 (ARK5)](https://attachments.academia-assets.com/69942899/thumbnails/1.jpg)
](Journal of Medicinal Chemistry, 2014
The success of imatinib, a BCR-ABL inhibitor for the treatment of chronic myelogenous leukemia, h... more The success of imatinib, a BCR-ABL inhibitor for the treatment of chronic myelogenous leukemia, has created a great impetus for the development of additional kinase inhibitors as therapeutic agents. However, the complexity of cancer has led to recent interest in polypharmacological approaches for developing multikinase inhibitors with low toxicity profiles. With this goal in mind, we analyzed more than 150 novel cyano pyridopyrimidine compounds and identified structure−activity relationship trends that can be exploited in the design of potent kinase inhibitors. One compound, 8cyclopentyl-2-[4-(4-methyl-piperazin-1-yl)-phenylamino]-7-oxo-7,8-dihydro-pyrido[2,3-d]pyrimidine-6-carbonitrile (7x), was found to be the most active, inducing apoptosis of tumor cells at a concentration of approximately 30−100 nM. In vitro kinase profiling revealed that 7x is a multikinase inhibitor with potent inhibitory activity against the CDK4/CYCLIN D1 and ARK5 kinases. Here, we report the synthesis, structure−activity relationship, kinase inhibitory profile, in vitro cytotoxicity, and in vivo tumor regression studies by this lead compound.
![Research paper thumbnail of Discovery of a Clinical Stage Multi-Kinase Inhibitor Sodium ( E )-2-{2-Methoxy-5-[(2′,4′,6′-trimethoxystyrylsulfonyl)methyl]phenylamino}acetate (ON 01910.Na): Synthesis, Structure–Activity Relationship, and Biological Activity](https://attachments.academia-assets.com/69942904/thumbnails/1.jpg)
](Journal of Medicinal Chemistry, 2011
Cyclin D proteins are elevated in many cancer cells and targeted deletion of Cyclin D1 gene in th... more Cyclin D proteins are elevated in many cancer cells and targeted deletion of Cyclin D1 gene in the mammary tissues protects mice from breast cancer. Accordingly, there is an increasing awareness of this novel non-enzymatic target for cancer therapeutics. We have developed novel, nonalkylating styryl benzyl sulfones that induce cell death in wide variety of cancer cells without affecting the proliferation and survival of normal cells. The development of derivatized Styryl Benzyl Sulfones followed logically from a tumor cell cytotoxicity screen performed in our laboratory that did not have an a priori target profile. Modifications of some of the precursor molecules led to lead optimization with regard to tumor cell cytotoxicity. In this report we describe the synthesis and structure-activity relationships of novel, non-alkylating (E) styryl benzyl sulfones, and the development of the novel anti-cancer agent sodium (E)-2-{2-methoxy-5-[(2′,4′,6′-trimethoxystyrylsulfonyl)methyl]phenylamino}-acetate (ON 01910.Na), which is in Phase III trials for myelodysplastic syndromes (MDS) associated with aberrant expression of cyclin D proteins.
Bioorganic & Medicinal Chemistry, 2010
Novel (E)-alpha-benzylthio chalcones are reported with preliminary in vitro activity data indicat... more Novel (E)-alpha-benzylthio chalcones are reported with preliminary in vitro activity data indicating that several of them are potent inhibitors (comparable to imatinib, the reference compound) of BCR-ABL phosphorylation in leukemic K562 cells, known to express high levels of BCR-ABL. The ability of such compounds to significantly inhibit K562 cell proliferation suggests that this scaffold could be a promising lead for the development of anticancer agents that are able to block BCR-ABL phosphorylation in leukemic cells.
A240 Cytokines mediate hematopoietic cell growth and differentiation via the JAK-STAT pathway and... more A240 Cytokines mediate hematopoietic cell growth and differentiation via the JAK-STAT pathway and aberrations in this pathway have been found to result in leukemogenesis. Thus, point mutations in the JAK2 kinase have been shown to be the causative molecular event in certain myeloproliferative disorders identifying JAK2 as a new molecular target for drug discovery. Here we report the discovery of a new class of kinase inhibitors, α-benzoyl styryl benzyl sulfides, which possess potent kinase inhibitory activity and exhibit cytotoxicity to human tumor cells. One of the compounds that belong to this class, ON 044580 was found to be a potent inhibitor of mutant JAK2 kinase and was non-ATPcompetitive. In vivo, it readily inhibited the proliferation of JAK2V617F-positiveleukemic cells and blocked the phosphorylation of JAK2 and STAT5. Interestingly, this compound was also found to inhibit the kinase activity of both wild type and imatinib resistant (T315I) forms of the BCR-ABL kinase, whic...
Journal of Clinical Oncology
Oncotarget
Overexpression and constitutive activation of CYCLIN D1 and Casein Kinase 2 are common features o... more Overexpression and constitutive activation of CYCLIN D1 and Casein Kinase 2 are common features of many hematologic malignancies, including mantle cell lymphoma (MCL) and leukemias such as T-cell acute lymphoblastic leukemia (T-ALL). Although both CK2 and CDK4 inhibitors have shown promising results against these tumor types, none of these agents have achieved objective responses in the clinic as monotherapies. Because both proteins play key roles in these and other hematological malignancies, we have analyzed the therapeutic potential of ON108110, a novel dual specificity ATP-competitive inhibitor of protein kinase CK2 as well as CDK4/6 in MCL and TALL. We show that in cell growth inhibition assays, MCL and TALL cell lines exhibited increased sensitivity to ON108110 when compared to other tumor types. Treatment with ON108110 reduced the level of phosphorylated RB-family proteins. In addition, ON108110 treatment resulted in concentration dependent inhibition of PTEN phosphorylation and a concomitant decrease in PI3K-AKT signaling mediated by CK2. Accordingly, cells treated with ON108110 rapidly accumulated in the G 0 /G 1 stage of the cell cycle as a function of increasing concentration followed by rapid onset of apoptosis. Together, these results indicate that dual inhibition of CK2 and CDK4/6 may be an efficient treatment of MCL and T-ALLs displaying upregulation of CK2/PI3K and CDK4 signaling pathways.
Journal of Pharmaceutical and Biomedical Analysis, Mar 5, 2013
ON 013100, (E)-2,4,6-trimethoxystyryl-3-hydroxy-4-methoxybenzyl sulfone, is a potent kinase inhib... more ON 013100, (E)-2,4,6-trimethoxystyryl-3-hydroxy-4-methoxybenzyl sulfone, is a potent kinase inhibitor whose phosphate form is in Phase I clinical trials in lymphoma and acute lymphoid leukemia. The objectives were to: (a) investigate the possible presence of the glucuronide metabolite of the drug in two representative colon cancer cell lines, a drug resistant (colo-205) and a drug sensitive (colo-320); (b) quantify the glucuronide metabolite and the unchanged drug in the cells after treatment with ON 013100. The glucuronide was synthesized and a selective LC/MS/MS method was developed and validated for the characterization and quantification of the metabolite. The glucuronide metabolite (570.6 Da) was found in the drug-resistant cells upon a 1h incubation with ON 013100 (20 μg/ml). After treatment with the drug, the concentration of the metabolite gradually decreased from 0.84 μg/ml at 0 h through 0.21 μg/ml at 6h to below detection limit of 8.0 ng/ml at 9 h. No glucuronide metabolite was detected in the drug-sensitive cells. The concentrations of intact ON 013100 in the drug-resistant cells gradually decreased from 0.41 μg/ml (0 h) to 0.06 μg/ml (9 h). The corresponding concentrations of the intact drug in the drug-sensitive cells were from 2.88 μg/ml to 0.94 μg/ml.
Synthesis Stuttgart, 2005
Bioorganic & Medicinal Chemistry, 2015
Several families of protein kinases have been shown to play a critical role in the regulation of ... more Several families of protein kinases have been shown to play a critical role in the regulation of cell cycle progression, particularly progression through mitosis. These kinase families include the Aurora kinases, the Mps1 gene product and the Polo Like family of protein kinases (PLKs). The PLK family consists of five members and of these, the role of PLK1 in human cancer is well documented. PLK2 (SNK), which is highly homologous to PLK1, has been shown to play a critical role in centriole duplication and is also believed to play a regulatory role in the survival pathway by physically stabilizing the TSC1/2 complex in tumor cells under hypoxic conditions. As a part of our research program, we have developed a library of novel ATP mimetic chemotypes that are cytotoxic against a panel of cancer cell lines. We show that one of these chemotypes, the 6-arylsulfonyl pyridopyrimidinones, induces apoptosis of human tumor cell lines in nanomolar concentrations. The most potent of these compounds, 7ao, was found to be a highly specific inhibitor of PLK2 when profiled against a panel of 288 wild type, 55 mutant and 12 lipid kinases. Here, we describe the synthesis, structure activity relationship, in vitro kinase specificity and biological activity of the lead compound, 7ao.
Bioorganic & medicinal chemistry
Journal of nuclear medicine : official publication, Society of Nuclear Medicine, 1999
Vasoactive intestinal peptide (VIP) is a naturally occurring 28-amino acid peptide with a wide ra... more Vasoactive intestinal peptide (VIP) is a naturally occurring 28-amino acid peptide with a wide range of biological activities. Recent reports suggest that VIP receptors are expressed on a variety of malignant tumor cells and that the receptor density is higher than for somatostatin. Our aims were to label VIP with 99mTc--a generator-produced, inexpensive radionuclide that possesses ideal characteristics for scintigraphic imaging--and to evaluate 99mTc-VIP for bioactivity and its ability to detect experimental tumors. VIP28 was modified at the carboxy terminus by the addition of four amino acids that provided an N4 configuration for a strong chelation of 99mTc. To eliminate steric hindrance, 4-aminobutyric acid (Aba) was used as a spacer. VIP28 was labeled with 1251, which served as a control. Biological activity of the modified VIP28 agonist (TP3654) was examined in vitro using a cell-binding assay and an opossum internal anal sphincter (IAS) smooth muscle relaxivity assay. Tissue d...
Bioorganic & medicinal chemistry, 2008
A series of 20 novel 1-(4-sulfamylphenyl)-3-trifluoromethyl-5-indolyl pyrazolines were designed, ... more A series of 20 novel 1-(4-sulfamylphenyl)-3-trifluoromethyl-5-indolyl pyrazolines were designed, synthesized, and screened in vitro for anti-inflammatory activity. These compounds were designed for evaluation as dual inhibitors of cyclooxygenases (COX-1 and COX-2) and lipoxygenases (LOX-5, LOX-12, and LOX-15) that are responsible for inflammation and pain. All pyrazoline molecules prepared are optically active and compounds that are more potent in COX-2 inhibitory activity (5a and 5f) were resolved by chiral column and each enantiomer was tested for cyclooxygenase inhibitory activity. Molecular modeling and comparison of molecular models of 5a enantiomers with that of celecoxib model shows that 5a (enantiomer-1) and 5a (enantiomer-2) have more hydrogen bonding interactions in the catalytic domain of COX-2 enzyme than celecoxib. Compounds 5a, 5e, and 5f showed moderate to good LOX-5 and LOX-15 inhibitory activity and this is comparable to that of celecoxib and more potent than rofeco...
Organic & Biomolecular Chemistry, 2013
A stereoselective and efficient method for free radical addition of benzyl thiol to aryl acetylen... more A stereoselective and efficient method for free radical addition of benzyl thiol to aryl acetylene in the presence of Et 3 B-hexane has been developed for the synthesis of (Z) and (E)-styryl benzyl sulfides where base catalyzed hydrothiolations have failed. The scope of this reaction was successfully extended for the synthesis of (E)-ON 01910•Na, a phase III clinical stage anti-cancer agent and its inactive geometrical isomer (Z)-ON 01910•Na. It is interesting to note that all the E-isomers synthesized have shown better cytotoxicity profile on cancer cells compared to the Z-isomers.
Journal of Pharmaceutical and Biomedical Analysis, 2013
ON 013100, (E)-2,4,6-trimethoxystyryl-3-hydroxy-4-methoxybenzyl sulfone, is a potent kinase inhib... more ON 013100, (E)-2,4,6-trimethoxystyryl-3-hydroxy-4-methoxybenzyl sulfone, is a potent kinase inhibitor whose phosphate form is in Phase I clinical trials in lymphoma and acute lymphoid leukemia. The objectives were to: (a) investigate the possible presence of the glucuronide metabolite of the drug in two representative colon cancer cell lines, a drug resistant (colo-205) and a drug sensitive (colo-320); (b) quantify the glucuronide metabolite and the unchanged drug in the cells after treatment with ON 013100. The glucuronide was synthesized and a selective LC/MS/MS method was developed and validated for the characterization and quantification of the metabolite. The glucuronide metabolite (570.6 Da) was found in the drug-resistant cells upon a 1h incubation with ON 013100 (20 μg/ml). After treatment with the drug, the concentration of the metabolite gradually decreased from 0.84 μg/ml at 0 h through 0.21 μg/ml at 6h to below detection limit of 8.0 ng/ml at 9 h. No glucuronide metabolite was detected in the drug-sensitive cells. The concentrations of intact ON 013100 in the drug-resistant cells gradually decreased from 0.41 μg/ml (0 h) to 0.06 μg/ml (9 h). The corresponding concentrations of the intact drug in the drug-sensitive cells were from 2.88 μg/ml to 0.94 μg/ml.
Journal of Medicinal Chemistry, 2008
Journal of Medicinal Chemistry, 2013
Journal of Medicinal Chemistry, 2012
Tubulin, the major structural component of microtubules, is a target for the development of antic... more Tubulin, the major structural component of microtubules, is a target for the development of anticancer agents. A series of (Z)-1-aryl-3-arylamino-2-propen-1-one (10) were synthesized and evaluated for antiproliferative activity in cell-based assay. The most active compound (Z)-1-(2-bromo-3,4,5-trimethoxyphenyl)-3-(3-hydroxy-4-methoxyphenylamino)prop-2-en-1-one (10ae) was tested in 20 tumor cell lines including multidrug resistant phenotype and was found to induce apoptosis in all these cell lines with similar GI(50) values. Flow cytometry studies showed that 10ae arrested the cells in G2/M phase of cell cycle. In addition to G2/M block, these compounds caused microtubule stabilization like paclitaxel and induced apoptosis via activation of the caspase family. The observations made in this investigation demonstrate that (Z)-1-Aryl-3-arylamino-2-propen-1-one (10) represents a new class of microtubule-stabilizing agents.
Journal of Medicinal Chemistry, 2014
The success of imatinib, a BCR-ABL inhibitor for the treatment of chronic myelogenous leukemia, h... more The success of imatinib, a BCR-ABL inhibitor for the treatment of chronic myelogenous leukemia, has created a great impetus for the development of additional kinase inhibitors as therapeutic agents. However, the complexity of cancer has led to recent interest in polypharmacological approaches for developing multikinase inhibitors with low toxicity profiles. With this goal in mind, we analyzed more than 150 novel cyano pyridopyrimidine compounds and identified structure−activity relationship trends that can be exploited in the design of potent kinase inhibitors. One compound, 8cyclopentyl-2-[4-(4-methyl-piperazin-1-yl)-phenylamino]-7-oxo-7,8-dihydro-pyrido[2,3-d]pyrimidine-6-carbonitrile (7x), was found to be the most active, inducing apoptosis of tumor cells at a concentration of approximately 30−100 nM. In vitro kinase profiling revealed that 7x is a multikinase inhibitor with potent inhibitory activity against the CDK4/CYCLIN D1 and ARK5 kinases. Here, we report the synthesis, structure−activity relationship, kinase inhibitory profile, in vitro cytotoxicity, and in vivo tumor regression studies by this lead compound.
Journal of Medicinal Chemistry, 2011
Cyclin D proteins are elevated in many cancer cells and targeted deletion of Cyclin D1 gene in th... more Cyclin D proteins are elevated in many cancer cells and targeted deletion of Cyclin D1 gene in the mammary tissues protects mice from breast cancer. Accordingly, there is an increasing awareness of this novel non-enzymatic target for cancer therapeutics. We have developed novel, nonalkylating styryl benzyl sulfones that induce cell death in wide variety of cancer cells without affecting the proliferation and survival of normal cells. The development of derivatized Styryl Benzyl Sulfones followed logically from a tumor cell cytotoxicity screen performed in our laboratory that did not have an a priori target profile. Modifications of some of the precursor molecules led to lead optimization with regard to tumor cell cytotoxicity. In this report we describe the synthesis and structure-activity relationships of novel, non-alkylating (E) styryl benzyl sulfones, and the development of the novel anti-cancer agent sodium (E)-2-{2-methoxy-5-[(2′,4′,6′-trimethoxystyrylsulfonyl)methyl]phenylamino}-acetate (ON 01910.Na), which is in Phase III trials for myelodysplastic syndromes (MDS) associated with aberrant expression of cyclin D proteins.
Bioorganic & Medicinal Chemistry, 2010
Novel (E)-alpha-benzylthio chalcones are reported with preliminary in vitro activity data indicat... more Novel (E)-alpha-benzylthio chalcones are reported with preliminary in vitro activity data indicating that several of them are potent inhibitors (comparable to imatinib, the reference compound) of BCR-ABL phosphorylation in leukemic K562 cells, known to express high levels of BCR-ABL. The ability of such compounds to significantly inhibit K562 cell proliferation suggests that this scaffold could be a promising lead for the development of anticancer agents that are able to block BCR-ABL phosphorylation in leukemic cells.