Annona muricata Leaf Extract Triggered Intrinsic Apoptotic Pathway to Attenuate Cancerous Features of Triple Negative Breast Cancer MDA-MB-231 Cells.

Annona muricata L., known as graviola, is an evergreen plant of the tropical regions and is a rich source of natural products. Graviola has various biological activities, and it is best known for its anticancer activity. This study aimed to investigate the effects of crude graviola extract in vitro on breast cancer cells; in particular, we aimed to identify an agent against triple negative breast cancer (TNBC). We used the TNBC MDA-MB-231 cell line as the experimental model and the ER(+) non-TNBC MCF-7 breast cancer cell line as the control. We identified annonaceous acetogenins, including annonacin isomers, characteristic to this plant by using liquid chromatography tandem mass spectrometry (LC/MS/MS). We observed a significant decrease in the cell viability in both cell lines within 48 h, whereas impaired cell motility and invasiveness were observed only in the MDA-MB-231 cell line. While the MCF-7 cells showed an ER-dependent mechanism of apoptosis, the apoptosis of MDA-MB-231 cells was governed by an intrinsic apoptotic pathway triggered by graviola leaf extract (GLE).

Bioassay-guided isolation of cantharidin from blister beetles and its anticancer activity through inhibition of epidermal growth factor receptor-mediated STAT3 and Akt pathways.

Cantharidin is an active constituent of blister beetles (cantharides) which have traditionally been used for cancer treatment. Several studies have shown that cantharidin has a cytotoxic effect on various cancer cells. However, few studies have examined the effect of cantharidin on signal transducer and activator of transcription 3 (STAT3) signaling in cancer. In this study, we isolated cantharidin from cantharides by bioassay-guided fractionation and examined its inhibitory effect on STAT3 activation in human breast cancer MDA-MB-231 cells, expressing high level of phosphorylated STAT3. Cantharides were extracted with acetonitrile and separated into hexane, methylene chloride/acetonitrile, and water fractions. The methylene chloride/acetonitrile fraction was further separated into four fractions by preparative high-throughput high-performance liquid chromatography. Cantharidin was then isolated from the third fraction by countercurrent chromatography and structurally determined by comparing nuclear magnetic resonance and high-resolution mass spectrometry data. Cantharidin inhibited STAT3 tyrosine phosphorylation in MDA-MB-231 cells. Cantharidin suppressed epidermal growth factor (EGF)-induced STAT3 and PI3K/Akt signaling pathways through inhibition of EGF receptor phosphorylation. Moreover, cantharidin reduced cell proliferation and induced apoptosis with downregulation of STAT3 target genes, such as Bcl-2, COX-2, and cyclin D1. Taken together, this study provides evidence that cantharidin may be a potential therapeutic agent for triple-negative breast cancer by reducing EGFR-mediated STAT3 and Akt signaling pathways.

Prevalence of delayed tooth development and its relation to tooth agenesis in Korean children.

OBJECTIVE: The aim of this study was to investigate the epidemiology of delayed tooth development (DTD) and the link between DTD and tooth agenesis (TA). DESIGN: The dental maturity of all of the developing permanent teeth of 4611 children (2417 males and 2194 females) was evaluated from panoramic radiographs. The prevalence of DTD and TA was analyzed, and gender difference for DTS and TA was investigated. The correlation of DTD and TA was investigated in intra-fields and inter-fields. RESULTS: The total prevalence of DTD among the 4611 children was 3.40%. The maxillary second premolar was the most frequently delayed tooth (1.02%), followed by the maxillary second molar (0.88%) and the mandibular second premolar (0.74%). DTD significantly correlated with TA in both intra-fields and inter-fields (p<0.05). CONCLUSIONS: The field of delayed development exhibited a significant correlation with that of TA.

Usefulness of acoustic radiation force impulse elastography in the differential diagnosis of benign and malignant solid pancreatic lesions.

PURPOSE: The aim of this study was to evaluate the tissue stiffness of solid pancreatic lesions by using acoustic radiation force impulse (ARFI) elastography to differentiate benign from malignant pancreatic lesions. METHODS: ARFI elastography was performed in 26 patients who had 27 focal solid pancreatic lesions, including 8 benign lesions (mass-forming pancreatitis, 5; autoimmune pancreatitis, 3) and 19 malignant lesions (pancreatic adenocarcinoma, 16; metastasis from colorectal cancer, 2; malignant neuroendocrine tumor, 1). On the elastographic images of virtual touch tissue imaging (VTI), the echogenicity of the mass was categorized on a 5-grade scale. On the elastographic image of virtual touch tissue quantification (VTQ), the shear wave velocities (SWVs) of the lesion and surrounding parenchyma were measured. RESULTS: On the VTI images, the mean echogenicity score of the malignant lesions (3.7±1.0) was higher than that of the benign lesions (3.1±0.4; P=0.023). On the VTQ images, there were no statistical differences in the mean SWV between the benign (2.4±1.1 m/sec) and malignant (3.3±1.0 m/sec) lesions (P=0.101). However, the mean SWV difference values between the lesion and background parenchyma of the malignant lesions (1.5±0.8 m/sec) were higher than those of the benign lesions (0.4±0.3 m/sec; P=0.011). CONCLUSION: ARFI elastography can determine the relative stiffness between a lesion and the background pancreatic parenchyma using VTI and VTQ, which is helpful in the differentiation between benign and malignant solid pancreatic lesions.

[A case of primary extragastrointestinal stromal tumor presenting as peritoneal dissemination].

Gastrointestinal stromal tumor (GIST) is the most common mesenchymal tumor of the gastrointestinal tract, but also occurs at a lower frequency in extra-gastrointestinal regions such as omentum, mesentery, retroperitoneum and undefined abdominal sites. This tumor is called extragastrointestinal stromal tumor (EGIST). EGIST is mostly diagnosed as a cystic mass, but rarely occurs as a disseminated abdominal tumor. We experienced a 70-year-old man with primary EGIST presenting as peritoneal dissemination. Abdominal CT showed diffuse peritoneal thickening with a large amount of ascites, but no definite mass lesion. Laparoscopic biopsy was performed and histologic findings showed tumor composed of epithelioid cells. In the results of immunohistochemical stains, the tumor showed positive reactivity with CD117 (c-kit), CD34, vimentin and actin, but negative reactivity with desmin and S-100 protein. On account of unresectability and histologic parameters of malignant behavior, he was started on imatinib.

A novel micelle-encapsulated platinum(II) anticancer agent.

A hydrophobic and water-insoluble platinum(II) compound, cis-(cha)(2)Pt(NO(3))(2) was encapsulated by macromolecular micelles self-assembled from an amphiphilic cyclotriphosphazene [NP(MPEG750)(GlyPheLeu)(2)Et](3) (CP750). The micelle-encapsulated platinum(II) compound exhibited outstanding pharmacokinetics in rats by showing long blood circulation and much larger systemic exposure (AUC=43.5 µgh/ml) compared with the free carboplatin (AUC=4.32 µgh/ml). Biodistribution study of the micellar platinum(II) compound using male Sprague-Dawley rats has shown excellent tumor to tissue ratios of 4.03 at 2h post injection and 4.67 at 24h post injection. Furthermore, the micellar platinum(II) compound exhibited more than 6 times higher cellular uptake in human cervical (HeLa) and lung (A549) tumor cells compared with the free platinum compound. Also it is surprising that the micellar platinum(II) compound displayed specifically high cytotoxicity against the stomach tumor cells (SNU638), which are one of the least responsive to chemotherapeutic agents currently in clinical use. The acute toxicity study has shown that the LD(50) values of free and the micellar cis-(cha)(2)Pt(NO(3))(2) are approximately 70 mg/kg and 90 mg/kg, respectively. Thus the platinum compound encapsulated by cyclotriphosphazene micelles is a promising candidate for preclinical studies.

Tripodal amphiphiles tunable for self-assembly to polymersomes.

Cyclotriphosphazenes grafted with equimolar amounts of a hydrophilic polyethylene glycol and a hydrophobic oligopeptide in cis-nongeminal way form a new class of tripodal amphiphiles allowing both intra- and intermolecular hydrophobic interactions that differ from linear block copolymer amphiphiles. It has been found in this study that the tripodal amphiphiles can be tuned for self-assembly from micelles to bilayered polymersomes by controlling the hydrophobicity of the oligopeptide grafted. For instance, the tripodal amphiphiles with an intermediate hydrophobicity (01) remain as stable micelles in aqueous solution. These biodegradable polymersomes exhibit outstanding physicochemical properties required for practical drug delivery and other biomedical applications. In particular, the cyclic phosphazene trimer platinated with a hydrophobic cis-bis(cyclohexylamine)Pt-moiety forms very stable polymersomes with excellent tumor selectivity by EPR effect and seems to be a promising candidate for preclinical studies.

[The change of cyclooxygenase-2 and inducible nitric oxide synthase in the gastric mucosa one year after eradication of Helicobacter pylori].

BACKGROUND/AIMS: The cyclooxygenase-2 (COX-2) and inducible nitric oxide synthase (iNOS), the proteins that have the role in the gastric carcinogenesis, are stimulated by H. pylori infection in the gastric mucosa. The aim of this study was to evaluate the expression of COX-2 and iNOS proteins one year after the eradication of H. pylori. METHODS: Gastric antral mucosa from fifty eight patients with chronic gastritis who were all infected with H. pylori was examined for the expression of COX-2 and iNOS proteins before and one year after the eradication of H. pylori by immunohistochemical stain. RESULTS: COX-2 and iNOS proteins were expressed in the epithelial cells and interstitial inflammatory cells of gastric mucosa. Percent expressions of COX-2 and iNOS were significantly decreased one year after the eradication in the patients with cured infection, but not in those having persistent H. pylori. COX-2 and iNOS expressions were well correlated with H. pylori density, acute and chronic inflammation of gastric mucosa. CONCLUSIONS: The eradication of H. pylori can decrease the expression of COX-2 and iNOS in the gastric mucosa in long-term period. This seems to be due to the removal of H. pylori itself and related regression of gastric inflammation.