Torasemide is a pyridine-sulfonylurea type loop diuretic mainly used for the treatment of edema associated with congestive heart failure, renal disease, or hepatic disease. Also for the treatment of hypertension alone or in combination with other antihypertensive agents. It is also used at low doses for the management of hypertension. It is marketed under the brand name Demadex. Torasemide inhibits the Na+/K+/2Cl--carrier system (via interference of the chloride binding site) in the lumen of the thick ascending portion of the loop of Henle, resulting in a decrease in reabsorption of sodium and chloride. This results in an increase in the rate of delivery of tubular fluid and electrolytes to the distal sites of hydrogen and potassium ion secretion, while plasma volume contraction increases aldosterone production. The increased delivery and high aldosterone levels promote sodium reabsorption at the distal tubules, and by increasing the delivery of sodium to the distal renal tubule, torasemide indirectly increases potassium excretion via the sodium-potassium exchange mechanism. Torasemide's effects in other segments of the nephron have not been demonstrated. Thus torasemide increases the urinary excretion of sodium, chloride, and water, but it does not significantly alter glomerular filtration rate, renal plasma flow, or acid-base balance. Torasemide's effects as a antihypertensive are due to its diuretic actions. By reducing extracellular and plasma fluid volume, blood pressure is reduced temporarily, and cardiac output also decreases.

Luteolin, 3',4',5,7-tetrahydroxyflavone, is a common flavonoid that exists in many types of plants including fruits, vegetables, and medicinal herbs. Plants rich in luteolin have been used in Chinese traditional medicine for treating various diseases such as hypertension, inflammatory disorders, and cancer. Luteolin possesses a variety of pharmacological activities, including antioxidant, anti-inflammatory, antimicrobial and anticancer activities. Numerous studies have shown that luteolin possesses beneficial neuroprotective effects both in vitro and in vivo.

Withaferin A is one of the most bioactive phytoconstituents of Withania somnifera, a well-known herb in Ayurvedic medical tradition of India. Due to the lactonal steroid's potential to modulate multiple oncogenic pathways, Withaferin A has gained much attention as a possible anti-neoplastic agent. Systematic research on the evaluation of anticancer activities of withaferin A was started around the 1970s. Since then, a large number of studies have demonstrated the ability of withaferin A to suppress the in vivo growth of various human cancer cells’ xenograft tumors as well as experimentally induced carcinogenesis in different rodent models. It has being reported that withaferin-A reduced the growth of human prostate cancer (PC3) cells tumor xenograft in nude mice by blocking the tumor angiogenesis and inducing intratumoral apoptosis. According to this study, i.p. administration of withaferin-A caused regression of implanted tumor cells by decreasing the expression of angiogenesis marker CD31, inducing the expression of proapoptotic protein Bax, and activating caspase-3 via inhibition of nuclear factor-κB (NF-κB) signaling pathway. In a separate study, intratumoral administration of withaferin-A arrested PC3 cells’ xenograft tumor growth in mice by inducing tumor cell death via upregulation of prostate apoptosis response-4 (Par-4). Anticancer activity of withaferin-A has also being demonstrated for gynecological cancer, melanoma, thyroid, gastrointestinal and other types of cancer. Mechanistic basis of the anticancer effects of withaferin-A includes: (1) reinforcement of cellular antioxidant and/or detoxification system; (2) suppression of inflammatory pathways; (3) selective inhibition of tumor cell proliferation and induction of apoptosis; (4) suppression of tumor angiogenesis; (5) blockade of epithelial-to-mesenchymal transition (EMT), tumor invasion, and metastasis; (6) alteration of tumor cell metabolism; (7) immunomodulation; and (8) eradication of cancer stem cells.

SNX-5422 (also known as PF-04929113) is a synthetic, novel, small molecule Hsp90 inhibitor with potential antineoplastic activity. Hsp90 is a molecular chaperone that plays a key role in the conformational maturation of oncogenic signaling proteins, such as HER2/ERBB2, AKT, RAF1, BCR-ABL, and mutated p53, as well as many other molecules that are important in cell cycle regulation or immune responses. Inhibition of Hsp90 by SNX-2112 may result in the proteasome degradation of oncogenic client proteins, including HER2/ERBB2, and the inhibition of tumor cell proliferation. SNX-5422 is originally developed by Pfizer and Serenex, Inc., and the phase I clinical trials for it has been completed in the treatment of solid tumors. Although the mechanism of action remains to be fully elucidated, SNX-5422, which is a prodrug, is rapidly converted to SNX-2112 that accumulates in tumors relative to normal tissues.

XL-888 is a highly potent and orally bioavailable ATP-competitive inhibitor of HSP90, a molecular chaperone protein that regulates the activity and stability of a range of key regulatory proteins, including a number of kinases implicated in cancer cell growth and survival. In preclinical studies, XL-888 has been shown to inhibit the proliferation of a broad panel of human tumor cell lines, and to induce marked degradation of HSP90 client proteins, including BRAF, MET, and HER2. XL-888 was discovered by Exelixis and is wholly owned by the company. XL-888 is currently in Phase I clinical trials for the treatment of malignant melanoma.

KW-2478 is a novel and potent non-ansamycin inhibitor of heat shock protein 90 designed to overcome the limitations, including low water solubility and hepatotoxicity, of 17-allylamino-17-demethoxygeldanamycin (17-AAG). KW-2478 exerts a strong antitumor activity against multiple myeloma (MM) cells with various chromosomal translocations. KW-2478 inhibits cell growth and apoptosis associated with Hsp90 client protein degradation. Recent study results have revealed that KW-2478 is able to deplete Hsp90 client Cdk9 and the phosphorylated 4E-BP1, a transcriptional kinase and a transcription inhibitor respectively, leading to reduced expression of FGFR3, c-Maf, and cyclin D1. KW-2478 suppresses tumor growth and induces the degradation of client proteins in tumors in NCI-H929 s.c. inoculated model at doses of 100 mg/kg or more. KW-2478 reduces both serum M protein and MM tumor burden in the bone marrow in OPM-2/GFP i.v. inoculated mouse model at doses of 100 mg/kg.

PU-H71 is experimental inhibitor of Hsp90. It is being tested in clinical trials against lymphoma and solid tumors.

Onalespib (AT13387; (2,4-dihydroxy-5-isopropyl-phenyl)-[5-(4-methyl-piperazin-1-ylmethyl)-1,3-dihydro-isoindol-2-yl] methanone, l-lactic acid salt), is wholly owned by Astex, a novel, high-affinity HSP90 inhibitor, which is currently being clinically tested, has shown activity against a wide array of tumor cell lines, including lung cancer cell lines. As a targeted inhibitor of Hsp90, onalespib has the potential to control the proliferation of multiple solid tumors and hematological malignancies where uncontrolled cell growth is dependent on the interaction between Hsp90 and its client proteins. Astex is pursuing an approach based on the observation that addition of onalespib to a molecularly targeted agent may delay the emergence of resistance to the agent, and hence prolong the window of therapeutic benefit. Onalespib is currently being evaluated via a CRADA with the National Cancer Institute (NCI) in various tumor types, and in a Phase 1/2 clinical study in combination with AT7519, Astex CDK inhibitor.

Arno Therapeutics is developing AR-12, an orally available, targeted therapy for cancer and infectious diseases. AR-12 is a potentially first-in-class, orally available, targeted anti-cancer agent that has been shown in preclinical studies to inhibit phosphoinositide-dependent protein kinase-1, or PDK-1, a protein in the PI3K/Akt pathway that is involved in the growth and proliferation of cells, including cancer cells. Although FDA-approved drugs that target the Akt pathway have shown efficacy in treating cancer, some tumors either do not respond to these drugs or eventually become resistant to therapy. Scientists hypothesize that a combination of drugs that inhibit different targets in this pathway could provide synergistic or additive benefits to increase efficacy and potentially overcome drug resistance. For this reason, there has been particular interest within the biopharmaceutical industry in developing inhibitors of PI3K, PDK-1, and Akt. AR-12 was licensed to Arno in January 2008 by The Ohio State University Research Foundation for commercial development by Arno as a potential treatment for solid tumors and hematological malignancies. In preclinical studies, AR-12 has shown efficacy in a wide range of tumor types, including breast, lung, prostate, pancreatic, brain and hematological cancers, as both a single-agent as well as in combination with leading oncology therapeutics. Also AR-12 represents a promising class of small molecules with broad-spectrum antifungal activity. AR-12 inhibits fungal acetyl coenzyme A (acetyl-CoA) synthetase in vitro and is fungicidal at concentrations similar to those achieved in human plasma. AR-12 has a broad spectrum of activity, including activity against yeasts (e.g., Candida albicans, non-albicans Candida spp., Cryptococcus neoformans), molds (e.g., Fusarium, Mucor), and dimorphic fungi (Blastomyces, Histoplasma, and Coccidioides) with MICs of 2 to 4 ug/ml. AR-12 is also active against azole- and echinocandin-resistant Candida isolates, and subinhibitory AR-12 concentrations increase the susceptibility of fluconazole- and echinocandin-resistant Candida isolates. Also AR-12 acts as a broad-specificity anti-viral drug in vitro and in vivo. AR-12 (OSU-03012) interacts with multiple chaperone proteins of the HSP90 family and the HSP70 family resulting in a broad spectrum of chaperone inactivation. This overall loss of chaperone functionality results in cells being more readily capable of undergoing autophagic processes and in cells that have a reduced competency for virus replication.

Alvespimycin (17-desmethoxy-17-N,N-dimethylaminoethylamino-geldanamycin) (17-DMAG; NSC 707545) is an inhibitor of the molecular chaperone heat shock protein HSP90. Alvespimycin is a derivative of antineoplastic benzoquinone antibiotic geldanamycin. Alvespimycin binds to HSP90, a chaperone protein that aids in the assembly, maturation and folding of proteins. Subsequently, the function of Hsp90 is inhibited, leading to the degradation and depletion of its client proteins such as kinases and transcription factors involved with cell cycle regulation and signal transduction. Alvespimycin was studied in clinical trials for the treatment of solid tumors and hematologic malignancies however its development was discontinued.