TRAIL (IC50 = 64.6±9.1 µM)

LY303511 is essentially identical to LY294002, with the exception that it does not efficiently inhibit PI3K because -O has taken the place of -NH in the morpholine ring. Increased calcein diffusion was seen in cells treated with LY303511, comparable to LY294002 levels. According to immunoblotting, LY303511 can enhance gap junction intercellular communication (GJIC), although this effect does not correspond with a decrease in AKT phosphorylation [1]. SHEP-1 neuroblastoma cells' TRAIL sensitivity is increased by LY303511 via upregulating death receptors and activating H2O2-MAPK. Different concentrations of TRAIL, LY303511 (LY30), and a combination of the two were applied to SHEP-1 cells (preincubation with LY303511 for 1 h, followed by incubation with TRAIL for 4 h). The viable fraction of SHEP-1 cells decreased by roughly 10%, 15%, and 30% at 25, 50, and 100 ng/mL, in response to TRAIL; however, cells treated with 12.5, 25, or 50 μM of LY303511 did not show the same response. Vitality has no impact. On the other hand, LY303511 (25 μM) incubation for one hour and 50 ng/mL TRAIL exposure for four hours resulted in a considerable synergistic impact (about 40% reduction in viable cells with LY303511+TRAIL compared with TRAIL alone), with viable cells declining by around 15%[2]. A negative control for PI3K activity is LY303511. Wortmannin (100 nM) did not affect whole-cell outward K+ currents in MIN6 insulinoma cells, while LY294002 and LY303511 caused the currents to be reversibly inhibited in a dose-dependent manner (IC50 9.0±0.7 μM and 64.6±9.1 μM, respectively). β-cells exhibit high expression levels of Kv2.1 and Kv1.4. In tsA201 cells transfected with Kv2.1, reversible current inhibition was observed at 50 μM LY294002 and 100 μM LY303511, respectively. With an IC50 of 64.6±9.1 µM, LY303511 inhibits current to a maximum of around 90% at 500 µM (n≥5 cells per concentration) [3].

When tumors grow to a volume of about 150 mm3, at which point 35 mice have developed a tumor, intraperitoneal treatment of vehicle or LY303511 (10 mg/kg/day) is carried out. Over 15% of the mice need to be put down after 21 days because to tumor growth that is too rapid; these data are suppressed since average tumor volume estimations are not accurate. It is sufficient to provide 10 mg/kg/day of LY303511 to prevent the formation of PC-3 tumors in vivo[4].

LY303511 is structurally identical to LY294002 except for a substitution of -O for -NH in the morpholine ring, and does not potently inhibit PI3K. Treatment of cells with LY303511 causes an increase in calcein spread similar to levels of LY294002. The ability of LY303511 to increase gap junctional intercellular communication (GJIC) does not occur concomitant with inhibition of phosphorylation of AKT as measured by immunoblotting.

Human neuroblastoma SHEP-1 cells are maintained in DMEM supplemented with 10% fetal bovine serum and 1% Penicillin. In a typical survival assay, LY303511 (12.5, 25, and 50 μM), TRAIL (25, 50, and 100 ng/mL), and a combination of the two (1 h preincubation with LY303511 followed by TRAIL for 4 h) are exposed to SHEP-1 cells (8×104 per well) plated in 24-well plates for 24 h. The crystal violet assay is used to determine cytotoxicity. Following drug exposure, cells are PBS washed and then incubated with 200 μL of crystal violet solution for 20 min. The remaining crystals are dissolved in 20% acetic acid after the excess crystal violet solution has been removed with distilled water. Using an automated ELISA reader, absorbance at 595 nm wavelength is used to assess viability. Cell viability experiments are performed similarly with 2,000 units/mL of catalase, 4 μM JNK inhibitor SP600125, 10 μM p38 inhibitor SB202190, 20 μM MAPK/ERK kinase (MEK) inhibitor PD98059, 50 μM of caspase-8 inhibitor Z-IETD-FMK or pan-caspase inhibitor Z-VAD-FMK, or death receptor blocking antibodies (4 μg/mL anti-DR4 or 1 μg/mL anti-DR5), or in cells transfected with small interfering RNA (siRNA) for silencing JNK and ERK expression, respectively. Before adding TRAIL, cells are pre-incubated for 1 hour with LY303511 and the appropriate inhibitor or catalase.

In zebrafish model, LY303511 inhibits CAL 27-xenografted tumor growth. Therefore, LY303511 displays antiproliferation potential against oral cancer cells in vitro and in vivo. https://pubmed.ncbi.nlm.nih.gov/31115172/

---

Human prostate adenocarcinoma (PC-3) cells (ATCC CRL-1435) are cultured and implanted (1×10~6 cells) in 20% Matrigel per athymic NCR nude mouse by subcutaneous injection at the flank. Inoculated mice are subdivided into four groups of 10. Administration of vehicle or LY303511, 10 mg/kg/day, is begun (day 1) when tumors reach ~150 mm3 (n=35), and tumor volumes are measured for 30 days at the indicated time points.[4]

[1]. Homotypic gap junctional communication associated with metastasis suppression increases with PKA activity and is unaffected by PI3K inhibition. Cancer Res. 2010 Dec 1;70(23):10002-11.

[2]. The phosphatidylinositol 3-kinase inhibitor LY294002 potently blocks K(V) currents via a direct mechanism. FASEB J. 2003 Apr;17(6):720-2.

[3]. LY303511 enhances TRAIL sensitivity of SHEP-1 neuroblastoma cells via hydrogen peroxide-mediated mitogen-activated protein kinase activation and up-regulation of death receptors. Cancer Res. 2009 Mar 1;69(5):1941-50.

[4]. LY303511 (2-piperazinyl-8-phenyl-4H-1-benzopyran-4-one) acts via phosphatidylinositol 3-kinase-independent pathways to inhibit cell proliferation via mammalian target of rapamycin (mTOR)- and non-mTOR-dependent mechanisms. J Pharmacol E. 2005 Sep;314(3):1134-43.

8-phenyl-2-(1-piperazinyl)-1-benzopyran-4-one is a N-arylpiperazine.
Loss of gap junctional intercellular communication (GJIC) between cancer cells is a common characteristic of malignant transformation. This communication is mediated by connexin proteins that make up the functional units of gap junctions. Connexins are highly regulated at the protein level and phosphorylation events play a key role in their trafficking and degradation. The metastasis suppressor breast cancer metastasis suppressor 1 (BRMS1) upregulates GJIC and decreases phosphoinositide-3-kinase (PI3K) signaling. On the basis of these observations, we set out to determine whether there was a link between PI3K and GJIC in tumorigenic and metastatic cell lines. Treatment of cells with the well-known PI3K inhibitor LY294002, and its structural analogue LY303511, which does not inhibit PI3K, increased homotypic GJIC; however, we found the effect to be independent of PI3K/AKT inhibition. We show in multiple cancer cell lines of varying metastatic capability that GJIC can be restored without enforced expression of a connexin gene. In addition, while levels of connexin 43 remained unchanged, its relocalization from the cytosol to the plasma membrane was observed. Both LY294002 and LY303511 increased the activity of protein kinase A (PKA). Moreover, PKA blockade by the small molecule inhibitor H89 decreased the LY294002/LY303511-mediated increase in GJIC. Collectively, our findings show a connection between PKA activity and GJIC mediated by PI3K-independent mechanisms of LY294002 and LY303511. Manipulation of these signaling pathways could prove useful for antimetastatic therapy.[1]

---

We recently reported that LY294002 (LY29) and LY303511 (LY30) sensitized tumor cells to drug-induced apoptosis independent of the phosphoinositide 3-kinase/Akt pathway. Here, we investigated the mechanism of LY30-induced sensitization of human neuroblastoma cells to TRAIL-mediated apoptosis. We provide evidence that LY30-induced increase in intracellular H(2)O(2) up-regulates the expression of TRAIL receptors (DR4 and DR5) in SHEP-1 cells by activating mitogen-activated protein kinases, resulting in a significant amplification of TRAIL-mediated caspase-8 processing and activity, cytosolic translocation of cytochrome c, and cell death. Involvement of the death receptors was further confirmed by the ability of blocking antibodies against DR4 and/or DR5 to inhibit LY30-induced TRAIL sensitization. Pharmacologic inhibition of c-Jun NH(2) terminal kinase (JNK) and extracellular signal-regulated kinase (ERK) activation by SP600125 and PD98059, respectively, blocked LY30-induced increase in sensitization to TRAIL-mediated death. Finally, small interfering RNA-mediated gene silencing of JNK and ERK inhibited LY30-induced increase in surface expression of DR4 and DR5, respectively. These data show that JNK and ERK are two crucial players involved in H(2)O(2)-mediated increase in TRAIL sensitization of tumor cells upon exposure to LY30 and underscore a novel mode of action of this inactive analogue of LY29. Our findings could have implications for the use of LY30 and similar compounds for enhancing the apoptotic sensitivity of neuroblastoma cells that often become refractory to chemotherapy.[3]

---

Mammalian target of rapamycin (mTOR), a serine/threonine kinase, regulates cell growth and proliferation in part via the activation of p70 S6 kinase (S6K). Rapamycin is an antineo-plastic agent that, in complex with FKBP12, is a specific inhibitor of mTOR through interaction with its FKBP12-rapamycin binding domain, thereby causing G(1) cell cycle arrest. However, cancer cells often develop resistance to rapamycin, and alternative inhibitors of mTOR are desired. 2-(4-Morpholinyl)-8-phenyl-4H-1-benzopyran-4-one (LY294002) blocks mTOR kinase activity, but it also inhibits phosphatidylinositol 3-kinase (PI3K), an enzyme that regulates cellular functions other than proliferation. We hypothesized that a close structural analog, 2-piperazinyl-8-phenyl-4H-1-benzopyran-4-one (LY303511) might inhibit mTOR-dependent cell proliferation without unwanted effects on PI3K. In human lung epithelial adenocarcinoma (A549) cells, LY303511, like rapamycin, inhibited mTOR-dependent phosphorylation of S6K, but not PI3K-dependent phosphorylation of Akt. LY303511 blocked proliferation in A549 as well as in primary pulmonary artery smooth muscle cells, without causing apoptosis. In contrast to rapamycin, LY303511 reduced G(2)/M progression as well as G(2)/M-specific cyclins in A549 cells. Consistent with an additional mTOR-independent kinase target, LY303511 inhibited casein kinase 2 activity, a known regulator of G(1) and G(2)/M progression. In addition to its antiproliferative effect in vitro, LY303511 inhibited the growth of human prostate adenocarcinoma tumor implants in athymic mice. Given its inhibition of cell proliferation via mTOR-dependent and independent mechanisms, LY303511 has therapeutic potential with antineoplastic actions that are independent of PI3K inhibition.[4]

C19H18N2O2

306.36

306.136

C, 74.49; H, 5.92; N, 9.14; O, 10.44

154447-38-8

LY 303511 hydrochloride;2070014-90-1; LY 303511;154447-38-8; 854127-90-5 (2HCl)

3971

Typically exists as solid at room temperature

1.2±0.1 g/cm3

496.1±45.0 °C at 760 mmHg

253.8±28.7 °C

0.0±1.3 mmHg at 25°C

1.627

3.22

1

4

2

23

464

0

O=C1C=C(N2CCNCC2)OC3=C(C4=CC=CC=C4)C=CC=C13

InChI=1S/C19H18N2O2/c22-17-13-18(21-11-9-20-10-12-21)23-19-15(7-4-8-16(17)19)14-5-2-1-3-6-14/h1-8,13,20H,9-12H2

2934.99.9001

Powder      -20°C    3 years

                     4°C     2 years

In solvent   -80°C    6 months

                  -20°C    1 month

Room temperature (This product is stable at ambient temperature for a few days during ordinary shipping and time spent in Customs)

Note: Listed below are some common formulations that may be used to formulate products with low water solubility (e.g. < 1 mg/mL), you may test these formulations using a minute amount of products to avoid loss of samples.

---

Injection Formulation 1: DMSO : Tween 80： Saline = 10 : 5 : 85 (i.e. 100 μL DMSO stock solution → 50 μL Tween 80 → 850 μL Saline)
*Preparation of saline: Dissolve 0.9 g of sodium chloride in 100 mL ddH ₂ O to obtain a clear solution.
Injection Formulation 2: DMSO : PEG300 ：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL DMSO → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)
Injection Formulation 3: DMSO : Corn oil = 10 : 90 (i.e. 100 μL DMSO → 900 μL Corn oil)
Example: Take the Injection Formulation 3 (DMSO : Corn oil = 10 : 90) as an example, if 1 mL of 2.5 mg/mL working solution is to be prepared, you can take 100 μL 25 mg/mL DMSO stock solution and add to 900 μL corn oil, mix well to obtain a clear or suspension solution (2.5 mg/mL, ready for use in animals).

View More

Injection Formulation 4: DMSO : 20% SBE-β-CD in saline = 10 : 90 [i.e. 100 μL DMSO → 900 μL (20% SBE-β-CD in saline)]
*Preparation of 20% SBE-β-CD in Saline (4°C，1 week): Dissolve 2 g SBE-β-CD in 10 mL saline to obtain a clear solution.
Injection Formulation 5: 2-Hydroxypropyl-β-cyclodextrin : Saline = 50 : 50 (i.e. 500 μL 2-Hydroxypropyl-β-cyclodextrin → 500 μL Saline)
Injection Formulation 6: DMSO : PEG300 : castor oil : Saline = 5 : 10 : 20 : 65 (i.e. 50 μL DMSO → 100 μLPEG300 → 200 μL castor oil → 650 μL Saline)
Injection Formulation 7: Ethanol : Cremophor : Saline = 10： 10 : 80 (i.e. 100 μL Ethanol → 100 μL Cremophor → 800 μL Saline)
Injection Formulation 8: Dissolve in Cremophor/Ethanol (50 : 50), then diluted by Saline
Injection Formulation 9: EtOH : Corn oil = 10 : 90 (i.e. 100 μL EtOH → 900 μL Corn oil)
Injection Formulation 10: EtOH : PEG300：Tween 80 : Saline = 10 : 40 : 5 : 45 (i.e. 100 μL EtOH → 400 μLPEG300 → 50 μL Tween 80 → 450 μL Saline)

---

Oral Formulation 1: Suspend in 0.5% CMC Na (carboxymethylcellulose sodium)
Oral Formulation 2: Suspend in 0.5% Carboxymethyl cellulose
Example: Take the Oral Formulation 1 (Suspend in 0.5% CMC Na) as an example, if 100 mL of 2.5 mg/mL working solution is to be prepared, you can first prepare 0.5% CMC Na solution by measuring 0.5 g CMC Na and dissolve it in 100 mL ddH2O to obtain a clear solution; then add 250 mg of the product to 100 mL 0.5% CMC Na solution, to make the suspension solution (2.5 mg/mL, ready for use in animals).

View More

Oral Formulation 3: Dissolved in PEG400
Oral Formulation 4: Suspend in 0.2% Carboxymethyl cellulose
Oral Formulation 5: Dissolve in 0.25% Tween 80 and 0.5% Carboxymethyl cellulose
Oral Formulation 6: Mixing with food powders

---

Note: Please be aware that the above formulations are for reference only. InvivoChem strongly recommends customers to read literature methods/protocols carefully before determining which formulation you should use for in vivo studies, as different compounds have different solubility properties and have to be formulated differently.

---

 (Please use freshly prepared in vivo formulations for optimal results.)