Rapid construction of substituted 3-amino-1,5-benzothiazepin-4(5H)-one dipeptide scaffolds through an Ugi-4CR - Ullmann cross-coupling sequence

A 3-step methodology for the synthesis of 1,5-benzothiazepin-4(5H)-one dipeptidomimetics has been elaborated via an Ugi-4CR followed by a S-trityl deprotection and an intramolecular Cu(i)-catalyzed Ullmann condensation with moderate to good yields. In silico and NMR conformational studies showed that the lowest energy conformers stabilize γ- and β-turn structures.

Efficient one-pot synthesis of amino-benzotriazolodiazocinone scaffolds via catalyst-free tandem Ugi-Huisgen reactions

Herein we describe a catalyst-free, one-pot procedure employing an Ugi-4CR between propargyl glycine, functionalised 2-azidoanilines, different isocyanides and aldehydes, followed by a thermal azide-alkyne Huisgen cycloaddition to generate a 14-member set of amino-benzotriazolodiazocine-bearing dipeptides with multiple points of diversification and high atom economy. These structures were derivatized by means of Suzuki-Miyaura cross-coupling reactions at two positions with good to excellent yields, leading to conformationally constrained tricyclic structures. In silico and NMR conformational analysis studies demonstrated that turn conformations are adopted by these structures.

Efficient synthesis of conformationally constrained, amino-triazoloazepinone-containing di- and tripeptides via a one-pot Ugi-Huisgen tandem reaction

Herein we describe a catalyst-free procedure employing an Ugi-4CR between a β-azido-α-amino acid, propargylamine, an isocyanide and an aldehyde, followed by a thermal azide-alkyne Huisgen cycloaddition to generate a 16-member library of amino-triazoloazepinone-bearing di- and tripeptides with up to four points of diversification and high atom economy.

Expression of CD133, a possible marker for cancer stem cells (CSCs), in small cell lung cancer (SCLC) cell lines and non- small cell lung cancer (NSCLC) cell lines

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Background: Cancer stem cell (CSCs) are believed to play important roles in tumor development, recurrence or metastasis. Identification of CSCs may have a therapeutic significance. CD133 expression has been shown on a minority of various human cancer cells with high capability of self-renewal and proliferation. Therefore, CD133 is thought to be one of possible markers for CSCs. Regarding human lung cancers, the existence, prevalence or roles of CD133 positive cells has not been fully understood. Methods: We examined CD133 mRNA by quantitative real-time PCR and sorted CD133-positive cells by fluorescence-activated cell sorting (FACS) using human small cell lung cancer(SCLC) and non-small cell lung cancer (NSCLC) cell lines. We evaluated differences of cell proliferation between CD133-positive and -negative cells by MTS assay in vitro and by subcutaneous injection for non- obese diabetic/severe combined immunodeficiency (NOD/SCID) mice in vivo. Results: CD133 expression was almost restricted in SCLC cell lines. CD133 mRNA expression or CD133-positive cell population was scarcely observed in NSCLC cell lines. In two SCLC cell lines examined (NCI-H82 and NCI-H69), CD133 positive cells had higher tumorgenicity both in vivo and in vitro than NSCLC cell lines. Conclusions: The expression status of CD133 is totally different between NSCLCs and SCLCs, probably reflecting the difference of these progenitor cells. Our results indicate that CD133-positive cells in SCLC cell are responsible for tumor growth. However, in view of their wide prevalence, CD133-positive cells do not seem to be a candidate for CSCs, at least in cell lines. To investigate the molecular and functional characteristics of CD133-positive cells may lead to a new therapeutic strategy for human lung cancers, especially for SCLCs.

No significant financial relationships to disclose.

The effect of TAE226 on the non-small cell lung cancer including Japanese origin lung cancer

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Background: Mutations in the epidermal growth factor receptor (EGFR) gene is the predictive factor for sensitivity of EGFR tyrosine kinase inhibitors (TKIs) in non-small cell lung cancer. Focal adhesion kinase (FAK) that is the downstream molecule of EGFR has been reported to be highly expressed in NSCLC suggesting novel therapeutic target of NSCLC. TAE226, dual inhibitor for FAK and insulin like growth factor-I receptor (IGF-IR), have been developed as anticancer reagent. In this study, we examined the effect of TAE226 on NSCLC from the view point of EGFR mutation status. Methods: We used NSCLC cell lines consisting of 4 EGFR mutant cell lines (PC9, H3255, HCC827, H1975) and 3 EGFR wild type cell lines (H1819, H1299, A549). We also used PC9 derived resistant cell line (RPC9). Antiproliferative effect of TAE226 on NSCLC cell lines was examined with MTS assay. The status of EGFR related molecules including its downstream signal pathway was investigated by western blotting analysis. The effect of TAE226 on xenograft mouse models was also examined. Results: TAE226 was effective on NSCLC cell lines with EGFR mutation including T790M mutation, compared to those with EGFR wild type. The value of IC50 (μmol/L) for PC-9, H3255, HCC827, H1975, RPC-9 and H1819, H1299, A549 was 0.16, 0.12, 0.086, 0.17, 0.31 and 4.7, 2.8, 1.4, respectively. Western blotting assay showed that TAE226 preferentially inhibited phosphor-EGFR and its downstream signaling mediators. We could confirm the anticancer effect of TAE226 on EGFR mutant cells was confirmed in xenograft mouse models. Conclusions: We indicated that TAE226 showed antitumor effect on EGFR mutant cell lines even T790M mutant cells. Further study is necessary to understand the mechanism of TAE226 effect on EGFR mutant cell lines. Our results suggest that TAE226 will be expected as the novel strategy for NSCLC.

No significant financial relationships to disclose.

Establishment and molecular characteristics of PC-9 derived erlotinib resistant cell lines

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Background: EGFR mutation is closely associated with tumor responsiveness to EGFR tyrosine kinase inhibitors (TKIs), gefitinib or erlotinib. However, many non-small cell lung cancer (NSCLC) cases with EGFR mutation that had responded to EGFR-TKIs finally acquire resistance to EGFR-TKIs. It has been reported that T790M mutation and MET amplification caused resistance to EGFR-TKIs . Recent study suggested that overexpression of HGF was also related to resistance to EGFR-TKIs. However, the whole mechanism of acquired resistance to TKIs is still not fully known. Methods: We established 5 clones of elrotinib resistant PC-9 cell line (harboring EGFR exon 19 deletion) (designated as PC-9ER1–5) by exposing PC-9 to low-dose erlotinib. The protein expression of EGFR-related molecules was examined by Western blotting. Array comparative genomic hybridization (aCGH) or real time quantitative PCR (qPCR) assay was performed to examine copy numbers of EGFR-related genes. Results: In MTS assay, the IC50 value for the parental PC-9 cells was 0.02 μmol/L. By contrast, those for PC-9ER1–5 were more than 33μmol/L. All 5 resistant cell lines retained exon19 deletions and did not obtain T790M mutation. The qPCR assay and aCGH showed no MET amplification in PC-9 or PC-9ER1–5. HGF protein was not overexpressed in PC-9ER1–5 by ELISA. The protein expressions of several molecules in the EGFR-Akt signaling pathway were examined by western blotting after erlotinib treatment. Although phospho-EGFR was suppressed in both PC-9 and PC-9ER1–5 with 2-μmol/L erlotinib, phospho-Akt was not suppressed in PC-9ER1–5. PTEN expression was not down-regulated in PC-9ER1–5. The combination of erlotinib and PHA-665752, MET tyrosine kinase inhibitor, did not suppress phospho-Akt or cell proliferation in PC-9ER1–5. Conclusions: As common molecular features of our EGFR-TKI resistant cell lines, phospho-Akt was not suppressed with exposure to erlotinib. These cell lines did not show previously reported features of resistant cell lines including T790M mutation, MET amplification or HGF overexpression. Our results indicated that other mechanisms leading to Akt activation caused resistance to EGFR-TKIs.

No significant financial relationships to disclose.

The antitumor effect of orally active heat shock protein 90 Inhibitor, 17-DMAG, on the growth of gefitinib-resistant non-small cell lung cancer

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Background: It has been reported that NSCLC cell lines with activating mutations of EGFRgene were significantly sensitive to Heat Shock Protein 90 (Hsp 90 ) ihibitors regardless of the secondary T790M mutation. Methods: We examined the antitumor effect of 17-dimethylaminoethylamino-17-demethoxygeldanamycin (17-DMAG), the orally active Hsp90 inhibitor, on the growth of NSCLC cell lines in vitro and in vivo. Results: In MTS assay, the IC50 values for 3 cell lines with EGFR mutation (PC-9, RPC-9, and NCI-H1975) ranged from 0.15 to 0.28 μM. RPC-9 is a gefitinib-resistant lung cancer cell line with the secondary T790M mutation established from PC-9. By contrast, those of 7 EGFR-wild type cell lines ranged from 1.63 to 28.5 μM. Western blot analysis revealed that mutant EGFRs were more readily depleted than wild-type EGFRs after the treatment of 17-DMAG. Furthermore, expression of phospho-Akt, phospho-MAPK, cdk4, and cyclin D1 was depleted after exposure to low concentrations of 17-DMAG in EGFR-mutant cells. Celeaved PARP expression confirmed apoptosis in response to 17-DMAG in EGFR-mutant cells. In animal models, 17-DMAG significantly reduced the growth of EGFR-mutant cell lines PC-9 and RPC-9 compared with controls and induced degradation of mutant EGFR. In contrast, 17-DMAG did not inhibit the growth of EGFR wild type cell lines compared with controls. Conclusions: These results suggested that 17-DMAG could become a novel therapeutic agent for patients with lung tumors expressing mutant EGFR and having developed clinical resistance to gefitinib.

No significant financial relationships to disclose.

[Extra-anatomical bypass for an atypical coarctation of aorta associated with hypertensive heart failure; report of a case]

A 60-year-old woman with hypertension for 40 years had presented the hypertensive heart failure due to an atypical coarctation of the aorta. The difference of blood pressure between upper and lower limbs reached 110 mmHg with taking 6 kinds of antihypertensive drugs. Her blood pressure declined without antihypertensive medication and heart failure got subsided after the extra-anatomical bypass of axillobilateral external iliac artery bypass. Extra-anatomical bypass for Takayasu's arteritis had enough effects to improve the hypertension and was supposed to have the advantages of decreasing the operative risk, and preventing the aneurysmal formation of anastomotic site rather than the thoracoabdominal aortic bypass.

[Bilateral coronary-pulmonary artery fistulae without cardiopulmonary bypass]

A 68-year-old female with heart failure was admitted on the probable diagnosis of patent ductus arteriosus. Coronary arteriography revealed the coronary-pulmonary artery fistulae which originated the bilateral coronary arteries. Excision of coronary artery fistulae was performed without cardiopulmonary bypass. The symptom of heart failure has been improved for postoperative 6 years. Coronary pulmonary artery fistula is commonly a meanders long and flowing into the pulmonary artery as one influx artery. We presume the surgical intervention without cardiopulmonary bypass would be adopted for the treatment of this type. Multidetector-row computed tomography (MD CT) is useful in verification to detect the perioperative fistulae.