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Theaflavin is a polyphenol found in black tea, along with related compounds theaflavin-3-gallate and Theaflavin-3,3’-digallate. Black tea, one of the most common beverages consumed worldwide, is made from the fermentation of green tea leaves. During this process, green tea polyphenols are modified into the theaflavins. These naturally occurring compounds demonstrate beneficial effects in a variety of diseases.

Recent studies have found that theaflavins reduce cell proliferation and induce apoptosis of ovarian cancer cells. These compounds also work against a cisplatin resistant ovarian cancer cell line A2780/CP70. Further studies with theaflavin-3, 3’-digallate showed that cells were arrested in the G2 stage of the cell cycle.

Additionally, theaflavins can act as anti-inflammatory compounds. When used in the LPS model for inflammation, theaflavin-3,3’-digallate decreased expression of cytokine inflammation markers TNFa, IL-1b, and IL-6. This occurred in both an in vitro and in vivo system, while showing very little cytotoxic effects.

An antimicrobial mechanism is postulated for Theaflavins. A recent manuscript shows that all of the theaflavins can inhibit 1-deoxy-D-xylulose 5-phosphate reductoisomerase (DXR), a key enzyme in bacterial terpenoid biosynthesis, in an uncompetitive manner.

The Theaflavin family of molecules is available from LKT Laboratories, Inc.

T286161 Theaflavin

T286165 Theaflavin-3-gallate

T286163 Theaflavin-3, 3’-digallate

References:

1. Gao Y., Rankin GO., Tu, Y., and Chen YC., “Inhibitory Effects of the Four Main Theaflavin Derivatives Found in Black Tea on Ovarian Cancer Cells.” Anticancer Res. 2016 Feb;36(2):643-51.

2. Tu Y., Kim E., Gao Y., et al. “Theaflavin-3,3’-digallate induces apoptosis and G2 cell cycle arrest through the Akt/MDM2/p53 pathway in cisplatin-resistant ovarian cancer A2780/CP70 cells.” Int. J. Oncol. 2016 Jun;48(6):2657-65. Doi: 10.3892/ijo.2016.3472.

3. Wu Y., Jin F., Wang Y., et al. “In vitro and in vivo anti-inflammatory effects of theaflavin-3,3’-digallate on lipopolysaccharide-induced inflammation.” Eur. J. Pharmacol. 2017 Jan 5;794:52-60. Doi:10.1016/j.ejphar.2016.11.027

4. Hui X., Yue, Q., Zhang DD., et al. “Antimicrobial mechanism of theaflavins: They target 1-deoxy-D-xylulose 5-phosphate reductoisomerase, the key enzyme of the MEP terpenoid biosynthetic pathway.” Sci Rep. 2016 Dec 12;6:38945. Doi: 10.1038/srep38945.

Sponges are known to produce secondary metabolites that act as chemical defense mechanisms. Because the sponge is a sessile organism with a fragile body, it has limited capability to defend itself otherwise. The sponge’s secondary metabolites act as chemical weapons and can ward off dangers such as attacking predators or bacterial infections. One of these secondary metabolites, produced by sponges belonging to the order Verongida, is the compound Aeroplysinin.

Aeroplysinin has been studied in several biological systems in the lab for its potential use against human diseases. Recently, Park, et al has done studies that indicate aeroplysinin attenuates the Wnt/b-catenin signaling in DLD-1 colon cancer cells. b-Catenin is involved in the development and progression of colon cancer, and so it may make a useful target on which to focus therapeutics or chemopreventive agents. Experimental treatment of HEK293 cells with aeroplysinin decreased the amount of intracellular b-catenin, meaning that aeroplysinin may make a useful chemopreventive agent and should be further investigated for this use.

In addition to showing inhibition of colon cancer, other studies have found aeroplysinin to demonstrate antibiotic, antimicrobial, antiviral, anti-inflammatory, and anti-angiogenic activities.

There are thousands of species of marine sponges alive today and each produces a unique set of secondary metabolites necessary for its own survival. Each of these secondary metabolites is a compound with some bioactivity that may provide a useful starting point for developing new compounds to battle human diseases.

Several compounds found in marine sponges are available from LKT Labs including:

A1865 Aeroplysinin

G0244 alpha-Galactosylceramide

M0255 Manzamine A

P8382 Puupehenone

V3212 Vidarabine

V3213 Vidarabine Monophosphate

Garcia-Vilas JA, Martinez-Poveda B, Quesada AR, Medina MA. Aeroplysinin-1, a sponge-derived multi-targeted bioactive marine drug. Mar Drugs. 2015 Dec 22;14(1):1. Doi: 10.3390/md14010001

Park S, Kim JH, Kim JE, et al. Cytotoxic activity of aeroplysinin-1 against colon cancer cells by promoting b-catenin degradation. Food Chem Toxicol. 2016 Jul;93:66-72. Doi: 10.1016/j.fct.2016.04.019

The NOTCH signaling pathway is involved in cell proliferation, differentiation and cell cycle progression. Four membrane-bound NOTCH receptors are found in mammals (NOTCH1, NOTCH2, NOTCH3 and NOTCH4), which interact with 5 different extracellular ligands (Jagged 1, jagged 2, delta like ligand 1, 3 and 4). Ligands bind NOTCH on the extracellular domain, starting the NOTCH signaling cascade, eventually resulting in release of the NOTCH intracellular domain (NICD). The NICD then translocates to the nucleus, effecting the activation of various genes, such as hairy/enhancer of split (HES).

γ-secretase is responsible for cleavage of the NOTCH intracellular domain from the transmembrane portion of the protein. Inhibitors of γ-secretase (GSIs) therefore are useful as inhibitors of the NOTCH signaling cascade. NOTCH signaling inhibitors have been extensively studied in hematological malignancies, as well as other cancerous tissues. LKT Laboratories offers a variety of γ-secretase inhibitors.

MK-0752 (3-[4-(4-chlorophenyl) sulfonyl-4-(2,5-difluorophenyl) cyclohexyl] propanoic acid) was also submitted for phase I clinical trials. Results of this test show that MK-0752 was tolerated by patients with advanced solid tumors, and showed efficacy as an anti-cancer agent.

DAPT (N-[N-(3,5- Difluorophenacetyl)-L-alanyl]-S-phenylglycine t-butyl ester) was found to inhibit the proliferation of ovarian cancer cells, as well as inducing apoptosis of these cells. DAPT also inhibits proliferation of gastric carcinmoma cells.

These γ-secretase inhibitors and more are available from LKT Labs Inc.

F4432 FLI-06

D0260 DAPT

D1773 Deshydroxy LY-411575

M4200 MK-0752

References:

Yuan X., Wu H., et al. “Notch signaling: An emerging therapeutic target for cancer treatment” Cancer Letters 369, (2015) pp 20-27. Doi: 10.1016/j.canlet.2015.07.048

Yao, Y., Ni, Y. et al. “The role of Notch signaling in gastric carcinoma: molecular pathogenisis and novel therapeutic targets.” Oncotarget. (2017) May 11. Doi: 10.18632/oncotarget.17809.

Feng, Z., Xu, W. et al. “Inhibition of gamma-secretase in Notch1 signaling pathway as a novel treatment for ovarian cancer.” Oncotarget. (2017) Jan 31; 8(5):8283-8293. Doi:10.18632/oncotarget.14152.

Gu, Y., Masiero, M. and Banham AH. “Notch signaling: its roles and therapeutic potential in hematological malignancies.” Oncotarget. (2016) May 17;7(20):29804-23. Doi: 10.18632/oncotarget.7772.

Mycotoxins are toxic compounds that are sometimes found as contaminants in food due to molds. They can be transferred through the food chain and may appear as contaminants in fruits, grains, crops, and any food products produced from these items, such as juices or cereals. Mycotoxins have a negative impact on human health as they can be carcinogenic, neurotoxic, and toxic to the endocrine and immune systems.

In some cases it may be possible to decontaminate food where mycotoxins are present. However, there are various restrictions worldwide on what processes may be used and there are limitations to the effectiveness of these methods. New decontamination methods, such as the exposure to cold atmospheric pressure plasma, are currently under development.

Due to personal choice and cultural differences in preferences of food, it is also difficult to set a safe and acceptable level of allowable contamination in the first place. Typically, the mycotoxins found with the lowest levels of acceptability set by many authorities are aflatoxins and ochratoxin, with limits in the single ppb range. However, each country sets its own limits.

Alternatively, Osteresch et al promote the idea of each individual’s exposure being assessed through a physiological sampling. They have recently developed a method to test dried blood spots or dried serum spots for 27 different mycotoxins in a single analysis. Samples can easily be collected by a minimally invasive method, generally by heel, ear, or finger pricking followed by spotting onto a filter paper card. By using individual biomonitoring, better understanding of human health impacts can be gained in the long run.

The data produced by a human biomonitoring program can provide insights not only to our individual and collective exposure but also to how that exposure may change over time. In addition, the long-term effects of consistent low-level exposure can be reassessed alongside environmental datasets to give us better insights on the risks to human health of exposures to these compounds.

Many mycotoxins, including ochratoxin and several of the aflatoxins are available at LKT Labs to be used as reference standards.

Mycotoxins

O0829 Ochratoxin A

A2044 Aflatoxin B1

A2046 Aflatoxin B2

A2048 Aflatoxin G1

A2050 Aflatoxin G2

A2052 Aflatoxin M1

A2054 Aflatoxin M2

A2244 Aflatoxicol

Mycotoxin Decontamination of Food: Cold Atmospheric Pressure Plasma versus “Classic” Decontamination. Toxins (Basel). 2017 Apr 28;9(5). PMID: 28452957

Multi-mycotoxin analysis using dried blood spots and dried serum spots. Anal Bioanal Chem. 2017 May;409(13):3369-3382. PMID: 28299415

A recent study published in PLoS ONE shows that the naproxen analog ATB 346 has chemopreventative effects in a murine cancer model.

ATB 346 is a hydrogen sulfide (H2S) releasing analog of naproxen, a non-steroidal anti-inflammatory drug (NSAID). It acts by inhibiting cyclooxygenase, and decreasing endogenous PGE2. ATB 346 does not have the same GI damaging effect as naproxen, however. Previous studies have shown that in mice, treatment with ATB 346 reduced traumatic brain injury by reducing inflammation and suppressing neural cell death.

In a study by Paul-Clark et al., the effect of ATB 346 was measured in APCMin/+ mice, a model for gastro-intestinal cancer. Researchers found that treatment with ATB 346 reduced the size and formation of intestinal polyps, pre-malignant lesions that form in this model. ATB 346 decreased the formation in comparison to the parent compound naproxen as well. Continuous treatment with ATB 346 significantly reduced polyp formation. Fourteen days of treatment significantly decreased the polyp score for APCMin/+ mice. The effect of ATB 346 was seen starting treatment at both week 6 and week 12 of life for the mice. Additionally, ATB 346 reduced expression of cMYC and β-catenin, two major cancer biomarkers. In all, the study shows that ATB 346 works better than naproxen in this mouse model, and does not exhibit the same GI side effects that appear with naproxen treatment.

ATB 346, as well as naproxen, is available from LKT Labs.

A7604 ATB 346

N0061 D-Naproxen

N0062 D, L-Naproxen

Campolo M., Esposito E. et al. “Hydrogen sulfide-releasing cyclooxygenase inhibitor ATB-346 enhances motor function and reduces cortical lesion volume following traumatic brain injury in mice” Journal of Neuroinflammation. 2014, 11:196 DOI: 10.1186/s12974-014-0196-1

Paul-Clark, M., Elsheikh W. et al., “Profound Chemopreventative Effects of a Hydrogen Sulfide-Releasing NSAID in the APCMin/+ Mouse Model of Intestinal Tumorigenesis” PLoS ONE (2016), 11(2):e0147289. Doi:10.1371/journal.pone.0147289

4-O-Methylhonokiol (M184770) is isolated from the bark of Magnolia officinalis along with the natural products honokiol and magnolol. This lignan has found utility in a range of research fields, from neuroscience to cancer.

Researchers have found that 4-O-Methylhonokiol can act as a neuroprotective agent, potentially by acting as an acetylcholinesterase inhibitor in mice. In a Morris water maze assay, after scopoloamine treatment to induce memory impairment, mice that received 4-O-Methylhonokiol performed better with reduced escape latency time compared with control mice. This was found in conjunction with suppressed acetylcholinesterase activity in mouse hippocampus and cortex with 4-O-Methylhonokiol treatment.

A similar study showed that 4-O-Methylhonokiol decreases the effect of LPS (lipopolysaccharides)-induced memory impairment in mice. In a Morris water maze experiment, mice performed better after LPS injection when treated with 4-O-Methylhonokiol, compared to control. Further experiments showed that 4-O-Methylhonokiol does this by inhibiting NF-κB, which in turn decreased the expression of Aβ1-42 in mouse brains. Additionally, 4-O-Methylhonokiol reduced expression of nitric oxide and PGE2, which are over-expressed in LPS-treated mice models.

More neuroprotective studies of 4-O-Methylhonokiol have shown that it increases the amount of 2-arachidonyl glycerol in mice brain by activating cannabinoid type-2 receptor (CB2), and acting as a substrate-specific inhibitor of COX-2. The inhibtion of COX-2 was shown by a decrease in the presence of PGE2 in mouse brain. This dual activity could allow for beneficial effects in neuroinflammatory states with over-expressed CB2 and COX-2 proteins.

In addition to neuroprotective studies, 4-O-methylhonokiol also has activity as an anti-cancer compound, as well as other disease states. 4-O-Methylhonokiol (M184770) is now available from LKT Laboratories, Inc. in 5, 10, 25, and 100 mg size bottles.

M184770 4-O-Methylhonokiol

H5654 Honokiol

M0125 Magnolol

Lee, Y. K., Yuk, D. Y. et al. “Protective effect of the ethanol extract of Magnolia officinalis and 4-O-methylhonokiol on scopolamine-induced memory impairment and the inhibition of acetylchlinesterase activity” J Nat Med. 2009 Jul; 63(3):274-282 PMID: 19343477

Lee, Y.J., Choi, D.Y. et al. “Inhibitory effect of 4-O-methylhonokiol on lipopolysaccharide-induced neuroinflammation, amyloidogenesis and memory impairment via inhibition of nuclear factor-kappaB in vitro and in vivo models” J Neuroinflammation. 2012 Feb 19;9:35 PMID: 22339795

Chicca, A. Gachet, M.S. et al. “4’-O-methylhonokiol increases levels of 2-arachidonoyl glycerol in mouse brain via selective inhibition of its COX-2-mediated oxygenation” J Neuroinflammation. 2015 May 13; 12:89 PMID: 25962384

Type 2 diabetes is a chronic condition in which the body resists the effects of insulin or doesn’t produce enough insulin to maintain a healthy glucose level. Since insulin is a hormone that regulates the the metabolism of sugar, type 2 diabetes typically leads to high blood sugar, which can lead to heart disease or kidney failure.

Sulforaphane, a natural compound found in broccoli, cauliflower, and other cruciferous vegetables, has been identified as a possible counter to type 2 diabetes. In a study published in June of 2017 by Lund University, R-Sulforaphane from LKT Labs was shown to suppress glucose production from hepatic cells by nuclear translocation of NRF2, and decreased the expression of important enzymes in gluconeogenesis. Sulforaphane also reversed the disease signature in the livers of diabetic animals. Finally, sulforaphane was also administered to obese patients with dysregulated type 2 diabetes, and was shown to reduce fasting blood glucose and glycated hemoglobin.

R,S-Sulforaphane is a synthetic organosulfur compound that displays a variety of interesting characteristics, including anticancer, antimicrobial, antioxidative, anti-inflammatory, and neuroprotective activities. It is a phase II enzyme inducer and induces the expression of the transcription factor Nrf2.

R-Sulforaphane is found naturally in cruciferous vegetables such as broccoli, and has been continuously studied for its health benefits, sometimes showing increased effectiveness compared to its synthetic R,S counterpart in various models.

S8044 R,S-Sulforaphane, High Purity (≥99%)

S8047 R,S-Sulforaphane, Research Grade (≥97%)

S8046 R-Sulforaphane, High Purity (≥99%)

S8048 R-Sulforaphane, Research Grade (≥97%)

1. Axelsson AS, Tubbs E, Rosengren AH, et al. “Sulforaphane reduces hepatic glucose production and improves glucose control in patients with type 2 diabetes.“. Sci Transl Med. 2017 Jun 14;9(394).

Tauopathies are a group of neurodegenerative diseases characterized by misfolding and abnormal accumulation of tau protein in the brain leading to the formation of neurofibrillary tangles. Some of these diseases include Alzheimer’s, Amyotropic lateral sclerosis, Argyrophilic brain disease, Parkinson’s, post traumatic stress disorder, and traumatic brain injury, just to name a few.

Although neurofibrillary tangles are strongly correlated with neurodegeneration, they are so far only known to be a correlation, and may not necessarily a causative factor.

In a study by McCormick et al, published in Biological Psychiatry, 1120 drugs were screened for activity against tau neurotoxicity. The chosen drugs already had FDA approval for human use, but are meant for a variety of other therapeutic uses, unrelated to tau. The goal of this study was to search out a known drug that also happens to target the underlying neurodegenerative pathology of tauopathies.

Finding new uses for already known drugs accelerates the process of discovery and clinical testing because the safety and toxicity profiles are already known.

This drug screen found a positive hit with one compound in particular: azaperone. Azaperone has previously been used in animals as a tranquillizer and as an antipsychotic. This study used a cuticle defective mutant of C. elegans, a roundworm in which most neuronal proteins are similar to human, as the test model.

The animals treated with azaperone produced reduced levels of insoluble tau, compared with untreated animals. Treatment was also shown to prevent loss of motor neurons. The test was carried forward into human HEK293 cells and was found to produce a U-shaped dose response curve. Using either too high or too low concentration of azaperone, the insoluble tau level increased.

Repositioning of known drugs into new uses may prove to be an efficient way to develop new therapies. While the correct dosage for an alternate use may need to be determined, the drug toxicity is already proven to be acceptable.

Many compounds with known therapeutic and toxicity profiles, including azaperone and several additional antipsychotics, are available at LKT Labs.

A9801 Azaperone

Antipsychotics available at LKT Labs

McCormick AV, Wheeler JM, et al. Dopamine D2 receptor antagonism suppresses tau aggregation and neurotoxicity. Biol Psychiatry. 2013 Mar 1;73(5):464-471. PMID: 23140663.

Sengupta U, Portelius E, et al. Tau oligomers in cerebrospinal fluid in Alzheimer’s disease. Ann Clin Transl Neurol. 2017 Mar 14;4(4):226-235. PMID: 28382304.

β-cembrenediol ((1S,2E,4R,6R,-7E,11E)-2,7,11-cembratriene-4,6-diol) is a diterpenoid that is isolated from the leaves of nicotiana tabacum (tobacco) plants. β-cembrenediol has been found to have neuro-protective effects in mice, reducing ischemic brain injury. The effect was found in both pre-treated and post-injury mice. It does this by increasing the phosphorylation of Akt, a well-known neuroprotective pathway. Additionally, β-cembrenediol and analogs have been found as anti-migratory compounds in wound healing assays with prostate cancer cells.

β-cembrenediol, and it’s C-4 epimer α-cembrenediol are in stock and available for research use.

C1649 β-cembrenediol

C1648 α-cembrenediol

C1650 β-cembrenediol Methyl Ether

Martins A. H. , Hu, J., et al. “Neuroprotective activity of (1S,2E,4R,6R,-7E,11E)-2,7,11-cembratriene-4,6-diol (4R) in vitro and In vivo in Rodent Models of Brain Ischemia” Neuroscience. 2015, Apr 16; 291: 250-259. Doi: 10.1016/j.neuroscience.2015.02.001

Baraka, H. N., Khanfar, M. A., et al. “Bioactive Natural, Biocatalytic, and Semisynthetic Tobacco Cembranoids” Planta Med 2011 Mar:77(5):467-476. Doi: 10.1055/s-0030-1250478.

LKT Laboratories provides custom analytical services for your naturally sourced products. These services include extraction, isolation, identification, quantitation, contamination testing and more. Our fully equipped lab includes UHPLC and LC/MS with ESI and APCI capabilities allowing for trace level detection. Our state-of-the-art analysis can can help solve a variety of your analytical and testing needs:

Quality control testing

Batch-to-batch variations

Stability testing in regular or accelerated storage conditions

Comparison testing of natural products with respect to different parts of the plant, such as seeds, leaves, bark, and roots, or with respect to different seasonal changes natural products undergo

Impurity testing

Product verification

Our friendly and responsive chemists are flexible to your needs and provide you with detailed reports and full documentation on the analysis.

Additionally, LKT also carries a variety of popular natural product standard kits to be used with your own analytic instruments. Besides standard samples, each kit also includes standard sample preparation instructions and liquid chromatogram testing conditions, so they can be easily used to screen your samples. Don’t have an HPLC? No problem! Contact us and we can do the analysis for you using your natural product samples.

AS112 Grape Skin Standards Kit

AS114 Citrus Flavonoids Standards Kit

AS111 Berry Flavonoids Standards Kit

AS109 Soy Isoflavone Standards Kit

AS107 Caffeic Acid Esters Standards Kit

AS104 Camptithecins Standards Kit

LKT Laboratories is pleased to introduce new options for those researchers working with the organosulfur compounds R,S-Sulforaphane and R-Sulforaphane. Both products are now offered at two different purity specifications: ≥99% and ≥97%. Investigators will have the freedom to pick the product that suits their research needs and budgetary constraints.

Sulforaphane is a molecule of significant importance to the scientific community. Since it was first studied in the early 90’s by Talalay, et al. at Johns Hopkins as a major inducer of anticarcinogenic, phase II enzymes, sulforaphane has seen a steady rise in research focus and publications. It has been a part of thousands of major studies, including a record 185 published works in 2016.

LKT Laboratories was the first company to make this compound commercially available in 1995, and continues to be its leading supplier. LKT’s purity standard over the past two decades has always been ≥98%, but with increasing demand for both ultra-pure material and flexibility for researchers, LKT is raising the purity specification on standard product to ≥99% (without increasing its price) as well as introducing the ≥97% version at reduced cost.

The new high purity ≥99% R,S-Sulforaphane and R-Sulforaphane are the purest materials commercially available. They are perfect for long-term projects that may involve animals or other prolonged application periods. Sulforaphane has strict storage requirements to preserve its stability and degrades much more quickly at lower starting purities, which is why LKT recommends the high purity version for projects such as these.

For those looking to use the compound in a shorter time frame, R,S-Sulforaphane and R-Sulforaphane may now be purchased at a ≥97% purity specification at a significantly reduced cost. For research with an immediate application, this product may be a more accessible option.

R,S-Sulforaphane is a synthetic organosulfur compound that displays a variety of interesting characteristics, including anticancer, antimicrobial, antioxidative, anti-inflammatory, and neuroprotective activities. It is a phase II enzyme inducer and induces the expression of the transcription factor Nrf2.

R-Sulforaphane is found naturally in cruciferous vegetables such as broccoli, and has been continuously studied for its health benefits, sometimes showing increased effectiveness compared to its synthetic R,S counterpart in various models.

S8044 R,S-Sulforaphane, High Purity (≥99%)

S8047 R,S-Sulforaphane, Research Grade (≥97%)

S8046 R-Sulforaphane, High Purity (≥99%)

S8048 R-Sulforaphane, Research Grade (≥97%)

1. Zhang Y, Talalay P, Cho CG, Posner GH (March 1992). “A major inducer of anticarcinogenic protective enzymes from broccoli: isolation and elucidation of structure“. Proc. Natl. Acad. Sci. U.S.A. 89 (6): 2399–2403.

Heat shock protein 90 (HSP90) is a molecular chaperone that plays a key role in protein folding and stabilization. Many HSP90 client proteins are overexpressed in cancer cells, and the cancer cells are dependent on HSP90 for growth and survival. Therefore, HSP90 has become a popular therapeutic target for many cancers.

In a recent study it was demonstrated that geldanamycin enhances retrograde transport of the bacterial protein toxin Shiga toxin to the Golgi apparatus in human epidermoid laryngeal carcinoma cells. This activity was shown to be partially mediated by activation of the p38-MK2 pathway, rather than a direct interaction with HSP90.

Although inhibition of HSP90 appears to be an effective target against cancer, geldanamycin is limited by its low aqueous solubility and high toxicity. Consequently, geldanamycin derivatives with improved pharmacological profiles have been developed. These include 17-Allylgeldanamycin and 17-Dimethylaminoethylamino demethoxygeldanamycin.

There are several interesting HSP90 inhibitors available through LKT Labs:

G1646 Geldanamycin

A0025 17-Allylaminogeldanamycin

D4802 17-Dimethylaminoethylamino demethoxygeldanamycin

A5313 Andrographolide

H1669 Herbimycin A

L8377 Luteolin

N5986 Novobiocin Sodium

W3576 Withaferin A

Dyve Lingelem AB, Hjelseth IA, et al. Geldanamycin enhances retrograde transport of Shiga toxin in HEp-2 cells. PLoS One. 2015 May 27;10(5):e0129214. PMID: 26017782.

LKT Labs is happy to announce its annual AACR iPad drawing winner for 2017 – Dr. Haiyan Xiao of Augusta University in Augusta, Georgia.

Dr. Xiao’s primary research focus is based on developing novel and effective vaccines to prevent or treat cancers. Her doctoral dissertation topic was, “Preventive and Therapeutic Roles of Lentiviral Vector Prime and Vaccinia Virus Boost in Mouse Melanoma.” Her dissertation research was published in several well-received articles in the Journal of Immunology. Dr. Xiao’s postdoctoral research is focused on examining how circulating leukocytes interact with the vascular endothelium during chronic inflammatory conditions such as cancer and sickle cell disease.

Dr. Xiao’s research goals are to study epigenetic changes in the immune system that may contribute to chronic conditions including obesity, diabetes, and cancer. By identifying changes, she hopes to develop new insights into the immunological impact of these chronic conditions. Ultimately, she hopes her research leads to the development of methods for preventing immunological complications associated with chronic conditions.

Researchers from past years hail from a variety of institutions, including:

2016 – Boston University; Boston, MA

2015 – The Wistar Institute; Philadelphia, PA

2014 – Vanderbilt University; Nashville, TN

Add your organization to the list of winners in 2018 when LKT Labs holds its next drawing at the AACR conference in Chicago, IL!

MYC is a frequently deregulated oncogene in many human cancers. It is normally responsible for facilitating cell growth and proliferation through the encoding of transcription factors. Since many types of cancers are dependent on the upregulation of MYC, reducing MYC protein levels by targeting its upstream regulators such as histone deacetylases (HDAC) and phophoinositide 3-kinases (PI3K) may be a viable and effective method of treatment.

CUDC-907 is an inhibitor of PI3K and class I and II HDACs. In a recent study published in Molecular Cancer Therapeutics, it was shown that PI3K and HDAC inhibition synergistically downregulated MYC protein levels and induced apoptosis in “double-hit” (DH) diffuse large B-cell lymphoma (DLBCL) cells. CUDC-907 suppressed the growth and survival of MYC-altered or MYC-dependent cancer cells through this downregulation of the MYC protein. Further research and development utilizing CUDC-907 in MYC-driven cancers may be pursued thanks to this study.

LKT Laboratories carries CUDC-907 as well as a number of other PI3K inhibitors for research use.

C8112 CUDC-907

PI3K inhibitor list

Kaiming S., Ruzanna A., et al. Dual HDAC and PI3K inhibitor CUDC-907 Downregulates MYC and Suppresses Growth of MYC-dependent Cancers. Mol Cancer Ther 2016.

Cabozantinib is a chemotherapeutic compound that has shown potential as a treatment for medullary thyroid cancer and other types of solid tumors. It is primarily known for its inhibition of c-Met and vascular endothelial growth factor receptor 2 (VEGFR-2). By inhibiting these tyrosine kinases Cabozantinib reduces tumor growth, metastasis, and angiogenesis.

In a 2016 study, cabozantinib showed activity against gastrointestinal stromal tumors (GIST). In many cases of GIST, oncogenic signaling is driven by KIT mutations. Tyrosine kinase inhibitors (TKI) such as imatinib have been used to treat GIST, but resistance to TKI caused by secondary mutations to KIT sometimes renders this treatment ineffective.

Cabozantinib was tested in patient-derived xenograft models of GIST, with each model carrying different KIT mutations. Three different models were examined in total, and in all three cabozantinib inhibited proliferative activity, even in those models that were imatinib-resistant. Compared to an imatinib treated group and a control group, cabozantinib also significantly reduced microvessel density in all three models.

From the study it was concluded that cabozantinib shows promising antitumor activity in both imatinib-sensitive and imatinib-resistant GIST models. The activity is achieved through the inhibition of tumor growth, proliferation, and angiogenesis, and may provide a valid alternate treatment method for GIST going forward.

C0006 Cabozantinib

I4802 Imatinib Mesylate

Gebreyohannes Y., Schoffski P., et al. Cabozantinib is Active against Human Gastrointestinal Stromal Tumor Xenografts Carrying Different KIT Mutations. Mol Cancer Ther; 15(12); 2845-52.

Piperlongumine is found in several species of the Piper plant and displays many beneficial characteristics, including antithrombotic, anti-inflammatory, anti-atherosclerotic, and chemotherapeutic activities. Isolated from the fruit of the long pepper, recent research has focused on the ability of this natural product to suppress tumor growth alone and in combination with other chemotherapeutic compounds.

In a study published in 2015, the effects of Piperlongumine were examined in pancreatic cancer cells. Pancreatic cancer is an aggressive malignancy with a relatively poor prognosis, even in cases where it is diagnosed early. There are few good options for chemotherapy.

In vitro, piperlongumine showed inhibition of pancreatic cancer cell lines, inhibited the activation of NF-kB, and also potentiated the apoptotic effects of gemcitabine, a nucleoside analog commonly used in the chemotherapeutic treatment of some cancers. Piperlongumine went on to show significant activity in vivo, where it suppressed tumor growth alone and enhanced the efficacy of gemcitabine in xenograft mouse models. These results were consistent with the downregulation of NF-kB activity and its target genes, decreased proliferation, and increased apoptosis in tumor remnants seen in the model.

The results of the study suggest both potential for piperlongumine as a stand-alone treatment for human pancreatic cancer, as well as a partner-chemotherapeutic with compounds like gemcitabine. Both piperlongumine and gemcitabine are available from LKT Labs for research use.

P3561 Piperlongumine

G1745 Gemcitabine Hydrochloride

Wang Y., Wu X., et al. Piperlongumine Suppresses Growth and Sensitizes Pancreatic Tumors to Gemcitabine in a Xenograft Mouse Model by Modulating the NF-kappa B Pathway. Cancer Prev. Res. Mar;9(3):234-44.

As of October 12th, 2016, LKT Laboratories has earned its MBE certification from the North Central Minority Supplier Development Council. The National Minority Supplier Development Council (NMSDC) advances business opportunities for certified minority business enterprises and is one of the nation’s leading corporate membership organizations.

End users may secure funding for resources provided by trusted minority-owned businesses such as those certified through the NMSDC. LKT Labs is proud to join this network of organizations.

Barasertib, also known as AZD-1152, is a highly selective aurora kinase B inhibitor. As an aurora kinase inhibitor, it has shown the ability to disrupt the cell cycle and consequently induce apoptosis in vitro. It has inhibited the growth of human colon, lung, and haematologic tumor xenografts in immunodeficient mice, and continues to be evaluated in various disease models.

In a 2016 study, barasertib inhibited the growth of small-cell lung cancer cells in vitro and in vivo. Small-cell lung cancer cells are good targets for aurora kinase inhibition, thanks to their rapid proliferation and high rates of MYC family amplification. Inhibitors of mitosis such as aurora kinase inhibitors have been effective in causing apoptosis in cells expressing high levels of MYC in other tumor types.

A panel of small-cell lung cancer lines with and without MYC family gene amplification was screened for growth inhibition by barasertib. The growth inhibition caused by barasertib correlated with cMYC amplification and cMYC gene expression in the panel. Small-cell lung cancer tumors with high cMYC amplification or gene expression may thus be good targets for barasertib and other aurora kinase B inhibitors.

LKT Labs sells a number of aurora kinase inhibitors, including AZD1152:

A9714 AZD-1152-HQPA

M4652 MLN-8237

T5996 Tozasertib

Z4900 ZM-447439 Trihydrate

References:

Helfrich B., Kim J., et al. Barasertib (AZD1152), a Small Molecule Aurora B Inhibitor, Inhibits the Growth of SCLS Cell Lines In Vitro and In Vivo. Mol Cancer Ther; 15(10); 2314-22. PMID: 27496133.