Serotonin receptor 2B induces visceral hyperalgesia in rat model and patients with diarrhea-predominant irritable bowel syndrome.

BACKGROUND: Serotonin receptor 2B (5-HT2B receptor) plays a critical role in many chronic pain conditions. The possible involvement of the 5-HT2B receptor in the altered gut sensation of irritable bowel syndrome with diarrhea (IBS-D) was investigated in the present study. AIM: To investigate the possible involvement of 5-HT2B receptor in the altered gut sensation in rat model and patients with IBS-D. METHODS: Rectosigmoid biopsies were collected from 18 patients with IBS-D and 10 patients with irritable bowel syndrome with constipation who fulfilled the Rome IV criteria and 15 healthy controls. The expression level of the 5-HT2B receptor in colon tissue was measured using an enzyme-linked immunosorbent assay and correlated with abdominal pain scores. The IBS-D rat model was induced by intracolonic instillation of acetic acid and wrap restraint. Alterations in visceral sensitivity and 5-HT2B receptor and transient receptor potential vanilloid type 1 (TRPV1) expression were examined following 5-HT2B receptor antagonist administration. Changes in visceral sensitivity after administration of the TRPV1 antagonist were recorded. RESULTS: Here, we observed greater expression of the 5-HT2B receptor in the colonic mucosa of patients with IBS-D than in that of controls, which was correlated with abdominal pain scores. Intracolonic instillation of acetic acid and wrap restraint induced obvious chronic visceral hypersensitivity and increased fecal weight and fecal water content. Exogenous 5-HT2B receptor agonist administration increased visceral hypersensitivity, which was alleviated by successive administration of a TRPV1 antagonist. IBS-D rats receiving the 5-HT2B receptor antagonist exhibited inhibited visceral hyperalgesia.Moreover, the percentage of 5-HT2B receptor-immunoreactive (IR) cells surrounded by TRPV1-positive cells (5-HT2B receptor I+) and total 5-HT2B receptor IR cells (5-HT2B receptor IT) in IBS-D rats was significantly reduced by the administration of a 5-HT2B receptor antagonist. CONCLUSION: Our finding that increased expression of the 5-HT2B receptor contributes to visceral hyperalgesia by inducing TRPV1 expression in IBS-D patients provides important insights into the potential mechanisms underlying IBS-D-associated visceral hyperalgesia.

The short inverted repeats-induced circEXOC6B inhibits prostate cancer metastasis by enhancing the binding of RBMS1 and HuR.

Circular RNAs (circRNAs) are a novel class of endogenous RNAs with a covalently closed loop structure. Many circRNAs have been found to participate in cancer progression. However, the detailed generation process, functions, and related mechanisms of circRNAs in prostate cancer (PCa) remain largely unknown. In the present study, we identified circEXOC6B, a novel suppressor in the metastasis of PCa. Functionally, circEXOC6B, originating from the exocyst complex component 6B (EXOC6B) gene, inhibited migration and invasion of PCa in vitro and in vivo. Mechanistically, by acting as a protein scaffold, circEXOC6B enhanced the binding of human RNA binding motif single strand interacting protein 1 (RBMS1) and human antigen R (HuR) and further increased A-kinase anchoring protein 12 (AKAP12) expression to inhibit PCa metastasis. Unlike previous studies, we found that one pair of short inverted repeats in flanking introns at least partly promoted the circularization of circEXOC6B. Our study presents a novel mechanism for the inhibitory role of circEXOC6B in PCa metastasis and provides new insight into the molecular process of circRNA generation.

1H NMR-based metabolomics of skin squamous cell carcinoma and peri-tumoral region tissues.

Squamous cell carcinomas (SCC) are the most frequent forms of skin malignancy. Knowledge of the metabolic changes occur in SCC and peri-tumoral region tissues is still limited. To investigate the metabolic changes in skin SCC and peri-tumoral regions, twenty-four patients with histopathology diagnosis of SCC were included in the study. Tissue samples were obtained from the SCCs, peri-tumoral regions (within 5 mm adjacent to the tumor margin) and distance normal tissues for control (> 5 mm adjacent to the tumor margin) from each patient. The metabolic changes of the three regions were investigated using 1H nuclear magnetic resonance-based metabolomics. Key metabolites in SCC were identified and validated by comparing with the other two regions. Eight metabolites were identified and validated between the SCCs and the controls, the concentrations of lactate, alanine, valine, creatine, aspartate, tyrosine, and glutamine significantly increased in SCC, while that of glucose decreased. The metabolomics analysis showed that lactate and valine were the key metabolites in SCCs and prei-tumoral regions. Pathways analysis showed that valine, leucine, and isoleucine biosynthesis, and pyruvate metabolism were the key abnormal metabolic pathways in SCC. Metabolomics analysis of key metabolites and pathways revealed that glycolysis, tricarboxylic acid (TCA) cycle, and amino acids metabolism played a central role in the metabolic of SCCs and peri-tumoral regions.

Stomatin-like Protein 2 Promotes Tumor Cell Survival by Activating the JAK2-STAT3-PIM1 Pathway, Suggesting a Novel Therapy in CRC.

Despite intensive efforts, a considerable proportion of colorectal cancer (CRC) patients develop local recurrence and distant metastasis. Stomatin-like protein 2 (SLP-2), a member of the highly conserved stomatin superfamily, is upregulated across cancer types. However, the biological and functional roles of SLP-2 remain elusive in CRC. Here, we report that high SLP-2 expression was found in CRC tissues and was linked to tumor progression and tumor cell differentiation. Additionally, high SLP-2 expression correlated with poor overall survival (OS) in CRC patients (p < 0.001). SLP-2 knockout (SLP-2KO), generated by CRISPR/Cas9, reduced cell growth, migration, and invasion; induced apoptosis in CRC cells; and reduced tumor xenograft growth in vivo. A 181-compound library screening showed that SLP-2KO produced resistance to JAK2 inhibitors (NVP-BSK805 and TG-101348) and a PIM1 inhibitor (SGI-1776), revealing that the JAK2-STAT3-PIM1 oncogenic pathway was potentially controlled by SLP-2 in CRC. In vitro and in vivo, TG-101348 combined with SGI-1776 was synergistic in CRC (combination index [CI] < 1). Overall, our findings suggest that SLP-2 controls the JAK2-STAT3-PIM1 oncogenic pathway, offering a rationale for a novel therapeutic strategy with combined SGI-1776 and TG-101348 in CRC. Additionally, SLP-2 may be a prognostic marker and biomarker for sensitivity to JAK2 and PIM1 inhibitors.

Iodine regulates G2/M progression induced by CCL21/CCR7 interaction in primary cultures of papillary thyroid cancer cells with RET/PTC expression.

Treatment with high iodine concentrations can delay oncogenic activation effects, reduce cell growth and return thyroid-specific gene and protein expression levels to normal. During rearranged during transfection (RET)/papillary thyroid carcinoma (PTC) 3 activation, excess iodine can act as a protective agent in thyroid follicular cells. The chemokine receptor CCR7 serves a critical role in lymphocyte trafficking into and within lymph nodes, the preferential metastatic site for PTC. However, the potential associations between chemokine (C­C motif) ligand 21 (CCL21)/C­C chemokine receptor type 7 (CCR7) interaction and iodine concentrations in primary cultures of PTC with RET/PTC expression remain unclear. Proliferation assays of primary cultures of PTC cells with RET/PTC1 and RET/PTC3 expression indicated that CCR7 activation by its specific ligand, CCL21, was associated with significantly increased cell proliferation. Flow cytometry data indicated that CCL21/CCR7 interaction significantly increased the fraction of cells in the G2/M phase of the cell cycle. Western blotting indicated that CCL21/CCR7 interaction significantly upregulated cyclin A, cyclin B1 and cyclin­dependent kinase 1 (CDK1) expression. Western blotting determined that CCL21/CCR7 interaction significantly enhanced the levels of phosphorylated extracellular signal­regulated kinase (P­ERK). Co-immunoprecipitation confirmed that there was interaction between P­ERK and cyclin A, cyclin B1 or CDK1, particularly in the presence of CCL21. Sodium iodide (NaI, 10-5 M) significantly abolished the effects of exogenous CCL21. These results suggest that CCL21/CCR7 interaction contributes to G2/M progression of RET/PTC­expressing cells via the ERK pathway in association with 10­5 M NaI.

Stomatin-like protein 2 is associated with the clinicopathological features of human papillary thyroid cancer and is regulated by TGF-ß in thyroid cancer cells.

Papillary thyroid cancer (PTC) accounts for 80-90% of all cases of thyroid malignancies. Stomatin-like protein 2 (SLP-2) is a novel member of the stomatin superfamily and is found in several types of human tumors. However, whether it is expressed in human PTC is unknown. In the present study, we aimed to explore the diagnostic value of SLP-2 in patients with PTC and to investigate whether SLP-2 expression is regulated by transforming growth factor-ß (TGF-ß), a cytokine which plays an important role in PTC tumorigenesis. A total of 107 patients consisting of 99 cases of classical and 8 cases of follicular variant PTC was examined. The expression of SLP-2 mRNA and protein was examined by immunohistochemistry (IHC) and qPCR, respectively. We found that SLP-2 was overexpressed in human PTC. The expression of SLP-2 was significantly associated with clinicopathological features of the PTC cases. Particularly, increased SLP-2 expression was mainly correlated with primary tumors >1 cm in size, with late stage tumors and with metastatic lymph nodes. The expression of SLP-2 was correlated with the expression of Ki-67, a cell proliferation marker, in PTC tissues as detected by IHC. SLP-2 was upregulated by TGF-ß1 in PTC cells as evaluated by western blotting. The present data revealed for the first time that patients with PTC exhibited SLP-2 overexpression that was associated with clinicopathological features. The correlation between SLP-2 expression and proliferation marker Ki-67 may be characteristic of PTC and may reflect PTC progression. SLP-2 was upregulated by TGF-ß1, indicating a possible role of SLP-2 in PTC tumorigenesis. Our data suggest that SLP-2 may be considered as a useful diagnostic marker and therapeutic target for PTC.

The miR-200 family regulates the epithelial-mesenchymal transition induced by EGF/EGFR in anaplastic thyroid cancer cells.

The miR-200 family was recently identified as a suppressor of epithelial-mesenchymal transition (EMT). The loss or gain of miR-200 family members is associated with cancer invasion. The epidermal growth factor receptor (EGFR) is overexpressed in the majority of anaplastic thyroid cancers (ATCs). The activation of EGFR by its ligand, epidermal growth factor (EGF), activates a signaling cascade that results in the enhanced migration and invasiveness of thyroid cancer cells. However, little is known about the potential interrelationships between EGF/EGFR, miR-200s and the induction of EMT or mesenchymal-epithelial transition (MET) processes. This study aimed to investigate the regulatory role of miR-200s in EMT modulation by EGF/EGFR. Using transfection, real-time reverse transcription PCR and western blot analysis, we found that the EGF treatment of Nthy-ori 3-1 thyroid follicular cells resulted in the downregulation of E-cadherin and the upregulation of vimentin. By contrast, EGFR silencing in SW1736 human thyroid carcinoma cells led to the upregulation of E-cadherin and the downregulation of vimentin. In addition, EGF signaling correlated with the reduced expression of miR-200s and the re-expression of miR-200s abrogated the effects of EGF treatment and restored an epithelial phenotype to EGF-induced Nthy-ori 3-1 cells. Conversely, the silencing of miR-200s in SW1736 cells overcame siEGFR-induced changes in gene expression and phenotype. In addition, we demonstrate that miR-200s play a key role in in vitro EGF/EGFR-mediated thyroid cell invasion and in EMT in vivo. We, therefore, provide a mechanistic link between the miR-200 family and EGF/EGFR, which suggests that miR-200 upregulation may serve as a novel therapeutic strategy for highly invasive thyroid cancers.

[Expression and significance of SARI and CCN1 in human colorectal carcinomas].

OBJECTIVE: To explore the expressions of SARI (suppressor of AP-1, regulated by IFN) and connective tissue growth factor/cysteine-rich 61/nephroblastoma-1 (CCN1) and clarify their influences on the occurrence, development and prognosis of colorectal carcinoma (CRC). METHODS: Real-time PCR (polymerase chain reaction) was used to confirm the expressions of SARI and CCN1 at the mRNA level in 32 fresh tissue samples. And the expressions of Caco-2, HT-29 and Lovo were also detected by RT-PCR (reverse transcription-PCR) in cell lines. Tissue specimens were obtained from 116 cases of CRC and the expressions of SARI and CCN1 for each specimen detected by immunohistochemistry. The correlations between the expressions of SARI and CCN1 proteins were summarized. The relationships between the expression levels of SARI and CCN1 and their clinical features in primary CRC were analyzed respectively. The effects of expression levels of SARI and CCN1 proteins on the prognosis were also assessed in 116 CRC cases. RESULTS: The expressions of SARI and CCN1 at the mRNA level in fresh cancerous tissues and cell lines decreased and became up-regulated respectively. The positive rate of SARI protein expression was 76.7% and 28.4% in cancerous and noncancerous tissues respectively (P < 0.05). The positive rate of CCN1 protein expression was 26.7% and 74.1% in cancerous and noncancerous tissues respectively (P < 0.05). A negative correlation was observed between the expressions of SARI and CCN1 (r = -0.24, P < 0.05). The negative expression of SARI correlated with a low grade of differentiation, deep infiltration depth and high TNM staging (P < 0.05). A positive expression of CCN1 correlated with deep infiltration depth and high TNM staging (P < 0.05) while a negative expression of SARI correlated with a lower survival rate than that of a positive expression (χ(2) = 8.47, P < 0.05); additionally, the survival rate of patients with a negative expression of SARI plus a positive expression of CCN1 was further lowered (χ(2) = 12.56, P < 0.05). CONCLUSION: The aberrant expressions of SARI and CCN1 correlate with the malignant biobehaviors of CRC. And a negative expression of SARI correlates with a worse prognosis of CRC.

[Multidetector-row CT evaluation of acute bowel ischemia induced by embolization of superior mesenteric artery in experimental porcine models].

OBJECTIVE: To evaluate the application of multi-detector row CT (MDCT) and CT angiography (CTA) for detecting early signs of acute bowel ischemia (ABI) in experimental porcine models. METHODS: Twelve pigs were assigned to four groups with 3 in each group. The digital subtraction angiography of superior mesenteric artery (SMA) and the embolization of branches of SMA with gelatin sponge and blood clot were performed by percutaneous transfemoral artery puncture and catheterization. MDCT pre- and post-contrast scanning in the arterial, venous and delay phase and CTA with three-dimensional reconstruction were carried out at pre-operation, 3 h, 6 h, 9 h, and 12 h after occlusion. The normal mesenteric vascular anatomy, arterial occlusion, mesentery and bowel changes, and dynamic change were evaluated. RESULTS: ABI changes were identified pathologically in all the 12 experimental pigs, and the severity of ischemia increased over time after embolization. CTA showed all 57 embolized branches of SMA and 29 of 34 unoccluded arterial branches with 5 false-positive vessel occlusions. The sensitivity and specificity of CTA were 100% and 85.3%, respectively. Thin-slab maximum intensity projection (TSMIP) revealed the disappearance of distal comb-like vessel branches and brush-like vasa recta, which were clearly delineated in the normal bowel segments. Using this criterion, TSMIP correctly defined 23 of 24 ischemic bowel segments and all the 12 normal bowel segments with a sensitivity of 95.8% and a specificity of 100%. CONCLUSIONS: MDCT and CTA reliably define normal and occluded mesenteric vessels in the pig. It can easily detect ischemic bowel segment by identified early changes of ischemia. The early direct ischemic signs are occluded vessels, the disappearance of distal comb-like branches or brush-like vasa recta, and poor bowel enhancement. The early indirect sign is bowel dilatation with fluid collection.

[The value of multislice spiral computed tomography in demonstrating the relationship between bronchus and peripheral lung cancer].

OBJECTIVE: To investigate the value of multislice spiral computed tomography (MSCT) in demonstrating the relationship between bronchus and peripheral lung cancer. METHODS: We prospectively performed volumetric targeted scans of 0.5 mm collimation with MSCT and reconstructed images of multiplanar reconstruction (MPR), curved multiplanar reformations (CMPR) and surface shaded display (SSD) in 53 peripheral lung cancers. The results were compared with macroscopic and microscopic specimens. RESULTS: (1) The third- to seventh-order branches of the bronchi were clearly shown in all patients by the designed protocol. CT demonstrated the tumor-bronchus relationship in 29 (96.7%) adenocarcinomas and 13 (76.5%) squamous-cell carcinomas. Statistic analysis showed that there was no significant difference between the two groups (chi(2) = 2.8, P > 0.05). (2) The tumor-bronchus relationship was identified as four types with MSCT. Type I: bronchus was obstructed abruptly by the tumor, type II: bronchus penetrated into the tumor with tapered narrowing and interruption, type III: bronchus lumen shown within tumor was patent and intact, type IV: bronchus ran at the periphery of the tumor with intact or narrowed lumen. (3) Type I was shown in 31 of 53 (58.5%) tumors with squamous-cell carcinoma slightly more common than adenocarcinoma. Type II and type III were seen equally in 8 of 53 (15.1%) tumors which occurred only in adenocarcinomas. Type IV was seen in 15 of 53 (28.3%) tumors with adenocarcinoma being slightly more frequent than squamous cell carcinoma. (4) The tumor at the fourth-order bronchus was more common in squamous cell carcinoma, whereas that at the fixth-order bronchus was more likely in adenocarcinoma. CONCLUSION: Volumetric targeted scan of ultra-thin section with MSCT and followed by MPR, CMPR and SSD reconstruction can greatly improve the manifestation of the bronchioles and accurately demonstrate the patterns of tumor-bronchus relationship, thereby reflecting pathologic changes to some extent.