Design, Synthesis, and Biological Evaluation of Proteolysis Targeting Chimeras (PROTACs) for the Dual Degradation of IGF-1R and Src.

A focused PROTAC library was developed to degrade both IGF-1R and Src proteins, which are associated with various cancers. PROTACs with IGF-1R and Src degradation potentials were synthesized by tethering different inhibitor warhead units and the E3 ligase (CRBN) recruiting-pomalidomide with various linkers. The designed PROTACs 12a-b inhibited the proliferation and migration of MCF7 and A549 cancer cells with low micromolar potency (1-5 µM) in various cellular assays.

MALAT1 promoted invasiveness of gastric adenocarcinoma.

BACKGROUND: Gastric cancer is the second leading cause of cancer globally, and the mechanism of its pathogenesis is still largely unknown. Recently, non-coding RNAs have been recognized to promote metastasis in various cancers, including gastric cancer. METHODS: We found that metastasis associated lung adenocarcinoma transcript-1 (MALAT1) is upregulated in gastric cancer tissue compared to adjacent normal tissue, as determined by microarray and subsequent qRT-PCR, then investigated the impact of MALAT1 on apoptosis, cell proliferation, and the cell cycle to dissect the carcinogenesis of gastric cancer, and examined mechanisms of invasion and metastasis. Expression of MALAT1 and U6 was determined by SYBR qRT-PCR in nine-teen gastric cancer cell lines and fifty fresh samples of cancer tissue and adjacent tissues. Downregulation of MALAT1 was accomplished with two different siRNAs. Cell proliferation was determined after treatment with these siRNAs. FACS using PI/Annexin-V staining was carried out. To analyze the invasiveness, a scratch wound-healing assay and a Matrigel invasion assay were performed. Cancer related gene expression assay was done after transfection of siR- MALAT1. RESULTS: The expression of MALAT1 was significantly elevated in various gastric cancer cell lines and gastric cancer tissues compared to normal cell lines and tissues (p < 0.01). siR-MALAT1 significantly reduced viable AGS cell numbers and induced apoptosis (p < 0.05). Deep invasion of tumor (advanced T stages) was more common in the high MALAT1-level group (p = 0.039). siR-MALAT1 significantly decreased AGS cell invasiveness and migration. siR-MALAT1 reduced expression of snail and N-cadherin, and elevated E-cadherin. The Wnt/ß-catenin related genes were significantly decreased by transfection of siRNA MALAT1. MALAT1 is involved in gastric carcinogenesis via inhibition of apoptosis and promotes invasiveness via the epithelial-to-mesenchymal transition. CONCLUSIONS: In our study, we found that deregulation of MALAT1 could be involved in both tumorigenesis and invasiveness in gastric cancer cells.

Long non-coding RNA HOTAIR promotes carcinogenesis and invasion of gastric adenocarcinoma.

Gastric cancer is one of the major causes of cancer death worldwide; however, the mechanism of carcinogenesis is complex and poorly understood. Long non-coding RNA HOTAIR (HOX transcript antisense RNA) recently emerged as a promoter of metastasis in various cancers including gastric cancer. Here we investigated the impact of HOTAIR on apoptosis, cell proliferation and cell cycle to dissect the carcinogenesis of gastric cancer. We examined the mechanism of invasion and metastasis and analyzed the clinical significance of HOTAIR. Downregulation of HOTAIR was confirmed by two different siRNAs. The expression of HOTAIR was significantly elevated in various gastric cancer cell lines and tissues compared to normal control. si-HOTAIR significantly reduced viability in MKN 28, MKN 74, and KATO III cells but not in AGS cells. si-HOTAIR induced apoptosis in KATO III cells. Lymphovascular invasion and lymph node metastasis were more common in the high level of HOTAIR group. si-HOTAIR significantly decreased invasiveness and migration. si-HOTAIR led to differential expression of epithelial to mesenchymal transition markers. We found that HOTAIR was involved in inhibition of apoptosis and promoted invasiveness, supporting a role for HOTAIR in carcinogenesis and progression of gastric cancer.

Facile approach to benzo[d]imidazole-pyrrolo[1,2-a]pyrazine hybrid structures through double cyclodehydration and aromatization and their unique optical properties with blue emission.

A modular approach to polycyclic N-fused heteroaromatics is described. Acid-catalyzed reactions of various 1-(2-oxo-2-arylethyl)-1H-pyrrole-2-carbaldehydes with several o-phenylenediamines provided facile access to a number of new benzo[d]imidazole-pyrrolo[1,2-a]pyrazine hybrid structures through double cyclodehydration and aromatization. Optical characterization of the synthesized compounds revealed unique emission properties, with deep blue emission in the aggregated and solid states, and a dramatic substituent effect was observed. Fusion of an additional benzene ring into the benzo[4,5]imidazo[1,2-a]pyrrolo[2,1-c]pyrazine scaffold resulted in a remarkable increase in the intensity of blue fluorescence from the solution along with good cell permeability and negligible phototoxicity, indicating the potential for bioimaging applications.

Tumor Microenvironment Remodeling by Intratumoral Oncolytic Vaccinia Virus Enhances the Efficacy of Immune-Checkpoint Blockade.

PURPOSE: Cancer immunotherapy is a potent treatment modality, but its clinical benefit depends on the tumor's immune profile. Here, we used mJX-594 (JX), a targeted and GM-CSF-armed oncolytic vaccinia virus, as a strategy to remodel the tumor microenvironment (TME) and subsequently increase sensitivity to αPD-1 and/or αCTLA-4 immunotherapy. EXPERIMENTAL DESIGN: The remodeling of the TME was determined using histologic, flow-cytometric, and NanoString immune profiling analyses. JX was intratumorally injected into implanted Renca kidney tumors or MMTV-PyMT transgenic mouse breast cancers with or without αPD-1 and/or αCTLA-4. Various combination regimens were used to evaluate immunotherapeutic anticancer responses. RESULTS: Intratumoral injection of JX remodeled the TME through dynamic changes in the immune system, as shown by increased tumor-infiltrating T cells and upregulation of immune-related gene signatures. This remodeling induced conversion of a noninflamed tumor into an inflamed tumor. JX virotherapy led to enhanced abscopal effects in distant tumors, with increased intratumoral infiltration of CD8+ T cells. A depletion study revealed that GM-CSF is an indispensable regulator of anticancer efficacy of JX. Dual-combination therapy with intratumoral JX and systemic αPD-1 or αCTLA-4 further enhanced the anticancer immune response, regardless of various treatment schedules. Of note, triple combination immunotherapy with JX, αPD-1, and αCTLA-4 elicited the most potent anticancer immunity and induced complete tumor regression and long-term overall survival. CONCLUSIONS: Our results show that intratumoral JX treatment induces dramatic remodeling of the TME and more potently suppresses cancer progression with immune-checkpoint blockades by overcoming resistance to immunotherapy.

Prospective Single Arm Study on the Effect of Ilaprazole in Patients with Heartburn but No Reflux Esophagitis.

PURPOSE: Patients with gastroesophageal reflux disease without esophagitis show varying responses to proton pump inhibitors (PPIs). The aim of this study was to objectively evaluate the effect of a new PPI, ilaprazole, on patients with heartburn but without reflux esophagitis. MATERIALS AND METHODS: This prospective study was performed on 20 patients with heartburn but without reflux esophagitis. All patients underwent upper endoscopy and 24-hr combined multichannel intraluminal impedance and pH esophageal monitoring (MII-pH). They were then treated with ilaprazole (20 mg) once daily for 4 weeks. The GerdQ questionnaire, histologic findings, and inflammatory biomarkers were used for assessment before and after ilaprazole. RESULTS: Among the 20 patients, 13 (65%) showed GerdQ score ≥8. Based on MII-pH results, patients were classified as true nonerosive reflux disease (n=2), hypersensitive esophagus (n=10), and functional heartburn (n=8). After treatment, patients showed a statistically significant improvement in GerdQ score (p<0.001). Among histopathologic findings, basal cell hyperplasia, papillary elongation, and infiltration of intraepithelial T lymphocytes improved significantly (p=0.008, p=0.021, and p=0.008; respectively). Expression of TNF-α, IL-8, TRPV1, and MCP-1 decreased marginally after treatment (p=0.049, p=0.046, p=0.045, and p=0.042; respectively). CONCLUSION: Daily ilaprazole (20 mg) is efficacious in improving symptom scores, histopathologic findings, and inflammatory biomarkers in patients with heartburn but no reflux esophagitis.

Clinicopathological Characteristics of Patients with Gastric Cancer according to the Expression of LIN28A.

BACKGROUND/AIMS: Although LIN28A is known to potentially play a role in the oncogenesis of various cancers, whether LIN28A expression is a predictor of poor prognosis in patients with gastric cancer has not been fully explored. We sought to evaluate clinicopathological characteristics according to the expression of LIN28A in numerous gastric cancer tissue samples. METHODS: LIN28A expression was evaluated by immunohistochemical (IHC) analysis of a tissue microarray comprising 288 gastric cancer tissues and 288 adjacent normal tissues. Clinicopathological characteristics, including overall survival, were compared according to LIN28A expression. RESULTS: The IHC staining score was lower for the cancer tissues than the normal tissues (p<0.001). However, no significant differences were observed in the clinicopathological characteristics between the low and high LIN28A expression groups. In addition, the 5-year overall survival rate did not differ between the two groups: 75.3% (95% confidence interval [CI], 69.3% to 81.7%) versus 71.6% (95% CI, 63.3% to 80.9%) for low versus high expression, respectively. CONCLUSIONS: The expression of LIN28A did not appear to play a distinct role in predicting the clinicopathological characteristics of patients with gastric cancer. In addition, LIN28A expression was not an independently associated factor for overall survival in patients with gastric cancer.

Promoter methylation of PCDH10 by HOTAIR regulates the progression of gastrointestinal stromal tumors.

HOTAIR, a long non-coding RNA (lncRNA), plays a crucial role in tumor initiation and metastasis by interacting with the PRC2 complex and the modulation of its target genes. The role of HOTAIR in gastrointestinal stromal tumors (GISTs) is remains unclear. Herein we investigate the mechanism of HOTAIR in the genesis and promotion of GISTs. The expression of HOTAIR was found to be higher in surgically resected high-risk GISTs than that in low- and intermediate-risk GISTs. Using GIST-T1 and GIST882 cells, we demonstrated that HOTAIR repressed apoptosis, was associated with cell cycle progression, and controlled the invasion and migration of GIST cells. Using a gene expression microarray and lists of HOTAIR-associated candidate genes, we suggested that protocadherin 10 (PCDH10) is a key molecule. PCDH10 expression was significantly decreased in GIST-T1 and GIST882 cells, possibly as a consequence of hypermethylation. We observed that HOTAIR induced PCDH10 methylation in a SUZ12-dependent manner. In this study, we found that the malignant character of GISTs was initiated and amplified by PCDH10 in a process regulated by HOTAIR. In summary, our findings imply that PCDH10 and HOTAIR may be useful markers of disease progression and therapeutic targets.