Metabolically inducing defects in DNA repair sensitizes -wild-type cancer cells to replication stress.

Metabolic reprogramming from oxidative respiration to glycolysis is generally considered to be advantageous for tumor initiation and progression. However, we found that breast cancer cells forced to perform glycolysis acquired a vulnerability to PARP inhibitors. Small-molecule inhibition of mitochondrial respiration-using glyceollin I, metformin, or phenformin-induced overproduction of the oncometabolite lactate, which acidified the extracellular milieu and repressed the expression of homologous recombination (HR)-associated DNA repair genes.

Identification of a dihydroorotate dehydrogenase inhibitor that inhibits cancer cell growth by proteomic profiling.

Dihydroorotate dehydrogenase (DHODH) is a central enzyme of the pyrimidine biosynthesis pathway and is a promising drug target for the treatment of cancer and autoimmune diseases. This study presents the identification of a potent DHODH inhibitor by proteomic profiling. Cell-based screening revealed that NPD723, which is reduced to H-006 in cells, strongly induces myeloid differentiation and inhibits cell growth in HL-60 cells.

Suppression of tumor metastasis by a RECK-activating small molecule.

RECK encodes a membrane-anchored protease-regulator which is often downregulated in a wide variety of cancers, and reduced RECK expression often correlates with poorer prognoses. In mouse models, forced expression of RECK in tumor xenografts results in suppression of tumor angiogenesis, invasion, and metastasis. RECK mutations, however, are rare in cancer genomes, suggesting that agents that re-activate dormant RECK may be of clinical value.

Identification of Dihydroorotate Dehydrogenase Inhibitors─Indoluidins─That Inhibit Cancer Cell Growth.

Dihydroorotate dehydrogenase (DHODH) catalyzes the rate-limiting step in de novo pyrimidine biosynthesis and is a promising cancer treatment target. This study reports the identification of indoluidin D and its derivatives as inhibitors of DHODH. Cell-based phenotypic screening revealed that indoluidin D promoted myeloid differentiation and inhibited the proliferation of acute promyelocytic leukemia HL-60 cells.

Mechanistic study of PpIX accumulation using the JFCR39 cell panel revealed a role for dynamin 2-mediated exocytosis.

5-aminolevulinic acid (5-ALA) has recently been employed for photodynamic diagnosis (ALA-PDD) and photodynamic therapy (ALA-PDT) of various types of cancer because hyperproliferating tumor cells do not utilize oxidative phosphorylation and do not efficiently produce heme; instead, they accumulate protoporphyrin IX (PpIX), which is a precursor of heme that is activated by violet light irradiation that results in the production of red fluorescence and singlet oxygen. The efficiencies of ALA-PDD and ALA-PDT depend on the efficient cellular uptake of 5-ALA and the inefficient excretion of PpIX. We employed the JFCR39 cell panel to determine whether tumor cells originating from different tissues can produce and accumulate PpIX.

Antitumor profile of the PI3K inhibitor ZSTK474 in human sarcoma cell lines.

Treatment of patients with advanced sarcoma remains challenging due to lack of effective medicine, with the development of novel drugs being of keen interest. A pan-PI3K inhibitor, ZSTK474, has been evaluated in clinical trials against a range of advanced solid tumors, with clinical benefit shown in sarcoma patients. In the present study, we developed a panel of 14 human sarcoma cell lines and investigated the antitumor effect of 24 anticancer agents including ZSTK474, other PI3K inhibitors, and those clinically used for sarcoma treatment.

High-throughput screening in colorectal cancer tissue-originated spheroids.

Patient-derived cancer organoid culture is an important live material that reflects clinical heterogeneity. However, the limited amount of organoids available for each case as well as the considerable amount of time and cost to expand in vitro makes it impractical to perform high-throughput drug screening using organoid cultures from multiple patients. Here, we report an advanced system for the high-throughput screening of 2427 drugs using the cancer tissue-originated spheroid (CTOS) method.

Antitumor effects of tyropeptin-boronic acid derivatives: New proteasome inhibitors.

The proteasome degrades numerous regulatory proteins that are critical for tumor growth. Thus, proteasome inhibitors are promising antitumor agents. New proteasome inhibitors, such as tyropeptins and tyropeptin-boronic acid derivatives, have a potent inhibitory activity.

In vitro multifaceted activities of a specific group of novel phosphatidylinositol 3-kinase inhibitors on hotspot mutant PIK3CA.

Background: As accumulating evidences suggest close involvement of phosphatidylinositol 3-kinase (PI3K) in cancer, novel PI3K inhibitors such as ZSTK474, GDC-0941, NVP-BEZ235 and BKM-120 have been developed for cancer therapy. A high frequency of hotspot mutations known as E542K, E545K and H1047R in the PIK3CA gene, which encodes the catalytic subunit of PI3Kα, has been found in various types of human cancers. The hotspot PIK3CA mutations also lead to resistance to therapeutics targeting epidermal growth factor receptor (EGFR), further suggesting that inhibition of hotspot mutant PIK3CA be required for a PI3K inhibitor as anticancer drug candidate.

AMF-26, a novel inhibitor of the Golgi system, targeting ADP-ribosylation factor 1 (Arf1) with potential for cancer therapy.

ADP-ribosylation factor 1 (Arf1) plays a major role in mediating vesicular transport. Brefeldin A (BFA), a known inhibitor of the Arf1-guanine nucleotide exchange factor (GEF) interaction, is highly cytotoxic. Therefore, interaction of Arf1 with ArfGEF is an attractive target for cancer treatment.

Discovery of phosphatidylinositol 3-kinase inhibitory compounds from the Screening Committee of Anticancer Drugs (SCADS) library.

Identification of new uses for existing drugs is known to be an efficient approach in drug discovery. The identification of a novel phosphatidylinositol 3-kinase (PI3K) inhibitor is important in terms of cancer chemotherapy because PI3K is implicated in many types of cancer. In an effort to discover new PI3K inhibitory compounds, we recently carried out a screening of Screening Committee of Anticancer Drugs (SCADS) library, a compound library mainly composed of antitumor drugs and kinase inhibitors.

Correlating phosphatidylinositol 3-kinase inhibitor efficacy with signaling pathway status: in silico and biological evaluations.

The phosphatidylinositol 3-kinase (PI3K) pathway is frequently activated in human cancers, and several agents targeting this pathway including PI3K/Akt/mammalian target of rapamycin inhibitors have recently entered clinical trials. One question is whether the efficacy of a PI3K pathway inhibitor can be predicted based on the activation status of pathway members. In this study, we examined the mutation, expression, and phosphorylation status of PI3K and Ras pathway members in a panel of 39 pharmacologically well-characterized human cancer cell lines (JFCR39).

Inhibition profiles of phosphatidylinositol 3-kinase inhibitors against PI3K superfamily and human cancer cell line panel JFCR39.

As accumulating evidences suggest close involvement of phosphatidylinositol 3-kinase (PI3K) in various diseases particularly cancer, considerable competition occurs in development of PI3K inhibitors. Consequently, novel PI3K inhibitors such as ZSTK474, GDC-0941 and NVP-BEZ235 have been developed. Even though all these inhibitors were reported to inhibit class I PI3K but not dozens of protein kinases, whether they have different molecular targets remained unknown.

Identification of candidate genes determining chemosensitivity to anti-cancer drugs of gastric cancer cell lines.

In order to efficiently develop improved cancer therapies it is important to predict the efficacy of anti-cancer drugs. In this regard, identification of genes that are related to drug sensitivity is vital. We previously established a panel of 39 human cancer cell lines (JFCR39) and a panel aiming for organ-specific analysis of 45 human cancer cell lines (JFCR45).

Synthesis and pharmacological evaluation of the novel pseudo-symmetrical tamoxifen derivatives as anti-tumor agents.

Four pseudo-symmetrical tamoxifen derivatives, RID-B (13), RID-C (14), RID-D (15), and bis(dimethylaminophenetole) (16), were synthesized via the novel three-component coupling reaction, and the structure-activity relationships of these pseudo-symmetrical tamoxifen derivatives were examined. It was discovered that 13 and 16 strongly inhibit the viability of the HL-60 human acute promyelocytic leukemia cell line, whereas 14 possesses a medium activity against the same cell line and 15 has no effect on the cell viability. The global anti-tumor activity of 13-16 against a variety of human cancer cells was assessed using a panel of 39 human cancer cell lines (JFCR 39), and it was shown that RID-B (13) strongly inhibited the growth of several cancer cell lines at concentrations of less than 1 microM (at 0.

Development and characterization of a model of liver metastasis using human colon cancer HCT-116 cells.

In order to develop a model of liver metastasis of human gastrointestinal cancer cells, we examined the potential of 10 human colon and stomach cancer cell lines (HT-29, WiDr, HCT-116, HCT-15, HCC-2998, MKN7, MKN28, MKN45, MKN74 and St-4) to form liver metastases in nude mice. Among the cell lines, HCT-116 cells consistently formed gross liver metastases when injected into the spleens of nude mice. In contrast, other human colon and stomach cancer cells produced little or no liver metastasis.

Evaluation of action mechanisms of toxic chemicals using JFCR39, a panel of human cancer cell lines.

We previously established a panel of human cancer cell lines, JFCR39, coupled to an anticancer drug activity database; this panel is comparable with the NCI60 panel developed by the National Cancer Institute. The JFCR39 system can be used to predict the molecular targets or evaluate the action mechanisms of the test compounds by comparing their cell growth inhibition profiles (i.e.

Antitumor activity of ZSTK474, a new phosphatidylinositol 3-kinase inhibitor.

Background: We previously synthesized a novel s-triazine derivative, ZSTK474 [2-(2-difluoromethylbenzimidazol-1-yl)-4,6-dimorpholino-1,3,5-triazine], that strongly inhibited the growth of tumor cells. We identified its molecular target, investigated its effects on cellular signaling pathways, and examined its antitumor efficacy and toxicity in vivo.

Methods: We used COMPARE analysis of chemosensitivity measurements from 39 human cancer cell lines and identified phosphatidylinositol 3-kinase (PI3K) as a molecular target for ZSTK474.

p53-defective tumors with a functional apoptosome-mediated pathway: a new therapeutic target.

Background: Although cancer cells appear to maintain the machinery for intrinsic apoptosis, defects in the pathway develop during malignant transformation, preventing apoptosis from occurring. How to specifically induce apoptosis in cancer cells remains unclear.

Methods: We determined the apoptosome activity and p53 status of normal human cells and of lung, colon, stomach, brain, and breast cancer cells by measuring cytochrome c-dependent caspase activation and by DNA sequencing, respectively, and we used COMPARE analysis to identify apoptosome-specific agonists.

Chemosensitivity profile of cancer cell lines and identification of genes determining chemosensitivity by an integrated bioinformatical approach using cDNA arrays.

We have established a panel of 45 human cancer cell lines (JFCR-45) to explore genes that determine the chemosensitivity of these cell lines to anticancer drugs. JFCR-45 comprises cancer cell lines derived from tumors of three different organs: breast, liver, and stomach. The inclusion of cell lines derived from gastric and hepatic cancers is a major point of novelty of this study.

Synthesis of functional proteins by mixing peptide motifs.

Here, we describe a synthetic approach for generating artificial proteins by the assemblage of naturally occurring peptide motifs. Two motifs respectively related to apoptosis induction and protein transduction were encrypted into different reading frames of an artificial gene (microgene), which was then polymerized; random frame shifts at the junctions between the microgene units yielded combinatorial polymers of three reading frames. Among the proteins created, #284 was found to penetrate through cell membranes and exert a strong apoptotic effect on several cancer cell lines.

Identification of candidate predictive markers of anticancer drug sensitivity using a panel of human cancer cell lines.

We previously investigated the correlations between the expression of 9216 genes and various chemosensitivities in a panel of 39 human cancer cell lines(1)) and found that the expression levels of AKR1B1 and CTSH were correlated with sensitivity and resistance to multiple drugs, respectively. To validate these correlations, we investigated the expression of these two genes and the chemosensitivities in 12 additional gastric cancer cell lines. The expression of AKR1B1 in the additional cell lines exhibited significant correlations with sensitivities to 8 of the 23 drugs examined, while that of CTSH displayed a significant negative correlation with only one (MS-247) of the 27 drugs examined.

Array-based structure and gene expression relationship study of antitumor sulfonamides including N-[2-[(4-hydroxyphenyl)amino]-3-pyridinyl]-4-methoxybenzenesulfonamide and N-(3-chloro-7-indolyl)-1,4-benzenedisulfonamide.

Compounds from sulfonamide-focused libraries have been evaluated in cell-based antitumor screens using the COMPARE analysis with a panel of 39 human cancer cell lines and flow cytometric cell cycle analysis. Thus far, 2 (N-[2-[(4-hydroxyphenyl)amino]-3-pyridinyl]-4-methoxybenzenesulfonamide (E7010)) and 3 (N-(3-chloro-7-indolyl)-1,4-benzenedisulfonamide (E7070)) have been selected from the collections as potent cell cycle inhibitors, which have progressed to clinical trials. Compound 2 is an orally active antimitotic agent disrupting tubulin polymerization, whereas compound 3 belongs to a novel class of antiproliferative agents causing a decrease in the S phase fraction along with G1 and/or G2 accumulation in various cancer cell lines.

An integrated database of chemosensitivity to 55 anticancer drugs and gene expression profiles of 39 human cancer cell lines.

To explore genes that determine the sensitivity of cancer cells to anticancer drugs, we investigated using cDNA microarrays the expression of 9216 genes in 39 human cancer cell lines pharmacologically characterized on treatment with various anticancer drugs. A bioinformatical approach was then exploited to identify genes related to anticancer drug sensitivity. An integrated database of gene expression and drug sensitivity profiles was constructed and used to identify genes with expression patterns that showed significant correlation to patterns of drug responsiveness.