Abstract The medicinal plant Withania somnifera has been used for over centuries in Indian Ayurvedic medicine to treat a wide spectrum of disorders. Withaferin A (WA), a bioactive compound that is isolated from this plant, has recently been found to have anti-inflammatory, immuno-modulatory, anti-angiogenic, and anti-cancer properties. Here we investigated malignant pleural mesothelioma (MPM) suppressive effects of WA and the molecular mechanisms involved. WA inhibited growth of the murine as well as patient-derived MPM cells in part by decreasing the chymotryptic activity of the proteasome that resulted in accumulation of ubiquitinated proteins. WA suppression of MPM growth also involved elevated apoptosis as evidenced by activation of caspase-3, elevated levels of pro-apoptotic Bax protein and cleavage of poly-(ADP-ribose)-polymerase. Our studies including gene-array based analyses further revealed that WA suppressed a number of cell growth and metastasis-promoting genes including c-myc. WA treatments also promoted cleavage of vimentin as well as stimulated expression of CARP-1/CCAR1, a novel transducer of cell growth signaling. Knock-down of CARP-1, on the other hand, interfered with vimentin cleavage and MPM growth inhibitory effects of WA. Administration of 5mg/kg WA by daily i.p injections inhibited growth of murine MPM cell-derived tumors in vivo in part by inhibiting proteasome activity and stimulating apoptosis. Together our in vitro and in vivo studies suggest that WA suppresses MPM growth by targeting multiple pathways that include blockage of proteasome activity and stimulation of apoptosis, and thus holds promise as an anti-MPM agent. Citation Format: {Authors}. {Abstract title} [abstract]. In: Proceedings of the 103rd Annual Meeting of the American Association for Cancer Research; 2012 Mar 31-Apr 4; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2012;72(8 Suppl):Abstract nr 2779. doi:1538-7445.AM2012-2779
In this study, we investigated in detail the role of cannabidiol (CBD), beta-caryophyllene (BC), or their combinations in diabetic peripheral neuropathy (DN). The key factors that contribute to DN include mitochondrial dysfunction, inflammation, and oxidative stress.
Abstract The fundamental limitations of conventional cancer treatment have promoted the development and application of nanoengineering platforms for achieving effective patient outcomes. Over a time, considerable clinical success has been accomplished in nanotechnology field but there are many challenges limiting the progress of nanomedicine from bench to the beside. The highly heterogeneous tumor environment, an inadequate understanding of interactions between tumor biomarkers and nanomedicine, and reproducibility in synthesis required for clinical translation are some of the major challenges. Thus, there is an urgent need to redirect our focus of nano-drug carrier that can target multiple components of tumor including, tumor epithelial cells, tumor angiogenic vessels, tumor hypoxia and stromal cells. To achieve this, we developed a library of various tumor biomarker targeting ligands, and drug and imaging agents encapsulated in nanoparticles (NPs). Finally, the library of targeting ligands was conjugated with NPs using reagent free ‘click' chemistry. This strategy will serve as an “off-the-shelf ready to configure drug formulation" that can be engineered based on a mix-and-match strategy for individual patient needs. It is envisaged that the patient can walk in the clinic and be given the targeted drug that is personalized to their need. For the proof-of-concept, we evaluated tumor selectivity of multiple cancer biomarker targeting oligo-micelles (OMs), iron oxide and lipid NPs in various patient derived tumor xenograft (PDx) models, such as non-small cell lung and triple negative breast cancer. We observed that the dual tumor hypoxia and cancer stem cell (CSC) targeting rod shaped OM has 8-fold higher tumor core penetration compared to non-targeted OM in these PDx tumors, as obtained from NIR-fluorescence imaging. This OM has significantly higher tumor vs. liver ratio and they follow tumor specific receptor competition. The tumor growth inhibition of drug loaded OM is superior compared to free drug. This approach demonstrated significant improvement of tumor stroma penetration with low healthy organ uptake of NPs portending more promising potentials for selective cancer treatment. Citation Format: Samaresh Sau, Hashem Alsaab, Katyayani Tatiparti, Ketki Bhise, Arun Rishi, Arun K. Iyer. Tumor multicomponent targeting nanoparticle library for personalized cancer therapy & imaging [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2018; 2018 Apr 14-18; Chicago, IL. Philadelphia (PA): AACR; Cancer Res 2018;78(13 Suppl):Abstract nr 4660.
Abstract The molecular complexity of cancers and therapy-associated side effects often limit effectiveness of many therapies, and warrant development of new agents for specific molecular targets while minimizing the off-target effects. Thus, our goal is to develop novel, safer and effective anti-cancer therapies on the basis of cell growth and survival inhibiting functions of an apoptosis regulatory protein, termed CARP-1. CARP-1 was identified by us as a novel target of select chemotherapy (adriamycin, etoposide, or Iressa)-dependent human breast cancer cell growth suppression. By conducting the high-throughput screening of chemical libraries, we identified a number of novel, small molecule compounds called CARP-1 Functional Mimetics (CFMs). MTT assay results showed that CFMs, as well as quinazoline analogues of CFMs, inhibited growth of a variety of cancer cells, including the drug-resistant breast cancer cell line MDA-MB 468, without affecting growth of immortalized mammary epithelial cells. Results of MTT assay indicated also that CFM-4 (1(2-chlorobenzyl)-5′-phenyl-3′H-spiro[indoline-3,2′-[1,3,4]thiadiazol]-2-one) was the most potent one. CFMs suppressed cancer cell growth in part by stimulating CARP-1 levels and promoting cell cycle arrest and apoptosis. RT-PCR assay results revealed that CFM-4 induced the extrinsic pathway of apoptosis via upregulation of TRAIL receptors, caspase-8 and caspase-3 which can then cleave multiple cellular proteins, leading to cancer cell death. Cancer-related deaths are often due to spread of cancers to other organ sites (metastasis) that involves invasion and movement of cancer cells through the nearby normal tissue and the lymph and blood vessels to reach other tissues to form secondary tumors. Here we also demonstrate that CFMs impact biological properties of cancer cells by inhibiting their movement and invasion through the membranes coated with the extra-cellular matrix. CFMs also inhibited abilities of cancer cells to grow as colonies in soft-agar. These proof-of-concept studies suggest that CFMs could induce cancer cell apoptosis and effectively inhibit migration and tumor-forming abilities of cancer cells. Thus CFMs or their analogues have potential as anti-cancer agents to target cancer cell proliferation, survival, migration, invasion and metastasis, and provide a strong basis for their development as anti-cancer agents. Citation Format: Abdelkader E. Ashour, Vino T. Cheryan, Shazia Jamal, Ahmed M. Alafeefy, Khairy M. Zoheir, Adel R. Abdallah, Arun K. Rishi. Mechanisms of inhibition of cancer cell growth and metastasis by novel small molecule compounds. [abstract]. In: Proceedings of the 104th Annual Meeting of the American Association for Cancer Research; 2013 Apr 6-10; Washington, DC. Philadelphia (PA): AACR; Cancer Res 2013;73(8 Suppl):Abstract nr 5512. doi:10.1158/1538-7445.AM2013-5512
Abstract Immune checkpoint blockade molecules, including antibodies against PD-1 and PD-L1 have gained much clinical recognition in the past few years. These strategies include harnessing the host's immune system to invade cancer cells by inhibiting the interaction between PD-1 and its ligand, PD-L1, thereby facilitating the activation of CD8+ T cells to mount an attack on cancer cells. Triple Negative Breast Cancer (TNBC) accounts for 10-20% of the total breast carcinoma cases. There is no FDA-approved targeted therapy for TNBC due to lack of the major biomarkers: estrogen, progesterone and HER-2. TNBC is difficult to treat, with a high rate of metastasis to nearby organs. We have identified the role of a hypoxia biomarker, carbonic anhydrase IX (CAIX) in proliferation and metastasis of TNBC. Based on this observation, we developed a CAIX-targeted Doxorubicin (Dox) prodrug nanoparticle, abbreviated as CAIX-Dox-NP. CAIX-Dox-NP can deliver the chemotherapeutic, Dox payload selectively in hypoxic tumor microenvironment, thus reducing Dox-associated cardiotoxicity. Most of the advanced stages TNBC solid tumors present themselves with oxygen-deficient, vascularized and matrix-rich core which is impermeable to most of the chemotherapy drugs. CAIX-Dox-NP has the ability to penetrate deep into the TNBC and kill epithelial tumor cells as well as tumor-growth promoting T-cells. CAIX-Dox-NP showed greater penetration in the core of hypoxic TNBC spheroid. Recent studies showed that Immunogenic Cell Death (ICD) has vital role in resurrecting the CD8+ T-cells mediated tumor killing. Combination of anti-PD-1 with inducers of ICD like Dox accentuate the ability of CD8+ T cells in killing of cancer cells. Our approach is to utilize CAIX-Dox for achieving CAIX-mediated targeted delivery and multimodal chemotherapy in addition to induction of ICD. Preliminary studies with CAIX-Dox has profound effect of killing TNBC cells, 4T1, through induction of early phase apoptosis. The Western Blot analysis in 4T1 treated with CAIX-Dox has proved the significant upregulation of ICD biomarkers, HMGB1 and calreticulin, by greater than 3-fold compared to control. To improve the bioavailability of CAIX-Dox, we developed CAIX-Dox-NP that can hitchhike on the circulating plasma albumin. The nanoparticles travel to the tumor and deliver the CAIX-Dox at the hypoxic core of TNBC, resulting in induction of apoptosis and ICD. Inspired from this outcome, we are developing a model for coculture of cancer and T-cells for evaluating if CAIX-Dox treatment can reeducate T-cells in killing cancer cells through ICD pathway. Citation Format: Ketki Bhise, Samaresh Sau, Mohd Ahmar Rauf, Arun K. Rishi, Arun K. Iyer. Hypoxia-targeting prodrug approach for multimodal chemotherapy and immunogenic cell death in aggressive triple negative breast cancer [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6263.
Total DNAs, isolated from a range of taeniid cestodes (Taenia solium, T. saginata, T. pisiformis, T. crassiceps, T. hydatigena, T. ovis, T. multiceps and T. taeniaeformis), have been subjected to restriction enzyme digestion, Southern transfer and hybridization analysis using cloned fragments of the ribosomal RNA gene of Schistosoma mansoni. Substantial inter-specific genetic differences have been revealed on the basis of characteristic hybridization patterns for each of the taeniid cestode species. Furthermore, a random genomic DNA library has been constructed in the vector plasmid pAT153 using DNA extracted from a pig isolate (Indian origin) of T. solium. A panel of taeniid cestode DNAs including DNA from Echinococcus granulosus, has been used in conjunction with hybridization and restriction enzyme analysis to identify in the library a single recombinant plasmid with a T. solium-specific insert (coded pTS10) and two recombinant plasmids with T. solium inserts having selective specificities for T. solium and T. ovis (coded pTS17) and T. solium, T. saginata, T. ovis and T. multiceps (coded pTS28). These recombinant plasmids and the cloned fragments of the ribosomal RNA gene of S. mansoni have been used in restriction endonuclease, Southern transfer and hybridization analysis to detect intra-specific genetic variation in cysticerci of T. solium from India, Mexico and Zimbabwe. In addition, pTS10 and pTS17 have been used in a simple dot-blot assay to distinguish T. solium from T. saginata.
Abstract CARP-1, a perinuclear phospho-protein, regulates cell survival and apoptosis signaling induced by genotoxic drugs. However, kinase(s) phosphorylating CARP-1 and down-stream signal transduction events remain unclear. Here we find that CARP-1 Serine (S)626 and Threonine (T)627 substitution to Alanines (AA) inhibits genotoxic drug-induced apoptosis. CARP-1 T627 is followed by a Proline (P), and this TP motif is conserved in vertebrates. To further elucidate chemotherapy-activated, CARP-1-dependent signaling mechanisms, we UV cross-linked protein extracts from Adriamycin-treated HeLa cervical cancer cells with a CARP-1 (614-638) peptide, and conducted liquid chromatography-tandem mass spectrometry (LC-MS/MS) analyses of the peptide-bound protein complexes. This experiment revealed SAPK p38γ interaction with CARP-1 (614-638) peptide. Our studies further revealed that SAPK p38γ phosphorylates CARP-1 T627 in cancer cells treated with genotoxic drugs. CARP-1 T627 phosphorylation was also noted in breast tumors from patients treated with radiation or endocrine therapies. Loss of p38γ abrogates CARP-1 T627 phosphorylation, and results in enhanced survival of breast cancer cells by genotoxic drugs. We conclude that genotoxic drugs activate p38γ-dependent CARP-1 T627 phosphorylation and cell growth inhibition. Citation Format: Jaganathan Venkatesh, Magesh Muthu, Vino T. Cheriyan, Sreeja C. Sekhar, Nuwan C. Acharige, Edi Levi, Hadeel Assad, Mary Kay Pflum, Arun K. Rishi. Phosphorylation of cell cycle and apoptosis regulatory protein (CARP)-1 by stress-activated protein kinase P38γ is a novel mechanism of apoptosis signaling by genotoxic chemotherapy [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2024; Part 1 (Regular Abstracts); 2024 Apr 5-10; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2024;84(6_Suppl):Abstract nr 1659.
Retinoids have been shown to influence pattern formation during development and regeneration in numerous systems such as limbs, vertebrae, and neural tube although there is little information about the effects of retinoids on pattern formation in visceral organs. We investigated the effects of exogenous retinoic acid on the in vitro pattern of airway branching and on lung epithelial cell differentiation. Histology, [3H]thymidine autoradiographies and reverse transcriptase/polymerase chain reaction (RT/PCR) amplification were used to assess the effects of retinoids and the expression of lung epithelial markers of differentiation. We found that retinoic acid interferes, in a dose-dependent fashion, with the expression of epithelial genes that are found in distal segments of the fetal lung (surfactant-associated proteins SP-A, SP-B, and SP-C). At high concentrations, retinoic acid (RA) dramatically altered the developmental pattern of the lung, favoring growth of structures that resemble proximal airways and concomitantly suppressing distal epithelial buds. We hypothesize that this in vitro "proximalizing" effect on the developing lung may be related to alterations in the expression of pattern-related genes.
