Assessing tumor angiogenesis in colorectal cancer by quantitative contrast-enhanced endoscopic ultrasound and molecular and immunohistochemical analysis

Quantitative evaluation of colorectal tumour vasculature using contrast-enhanced ultrasound: Correlation with angiogenesis and prognostic significance

BACKGROUND

Ultrasound is a vital tool for the diagnosis and management of colorectal cancer (CRC). Contrast-enhanced ultrasound (CEUS) is a non-invasive, safe, and cost-effective method for evaluating tumour blood vessels, that play a crucial role in tumour growth and progression.

AIM

To explore CEUS's role in the quantitative evaluation of CRC blood vessels and their correlation with angiogenesis markers and prognosis.

METHODS

This study prospectively enrolled 100 patients with CRC confirmed by histopathology. All patients received preoperative CEUS examinations. Quantitative parameters, such as peak intensity (PI), time to peak (TTP), and area under the curve (AUC), were derived from time-intensity curve (TIC) analysis. Tumour tissue samples were obtained during surgery and examined immunohistochemically to assess the expression of angiogenesis markers, including vascular endothelial growth factor (VEGF) and microvessel density (MVD). The correlation between CEUS parameters, angiogenesis markers, and clinicopathological features was evaluated using appropriate statistical tests.

RESULTS

Quantitative CEUS parameters (PI, TTP, and AUC) showed significant correlations with VEGF expression (P < 0.001) and MVD (P < 0.001), indicating a strong link between tumour blood vessels and angiogenesis. Increased PI, reduced TTP, and expanded AUC values were significantly related to higher tumour stage (P < 0.001), lymph node metastasis (P < 0.001), and distant metastasis (P < 0.001). Furthermore, these parameters were recognized as independent predictors of overall survival and disease-free survival in multivariate analysis (P < 0.001).

CONCLUSION

CEUS has a high potential in guiding treatment planning and predicting patient outcomes. However, more comprehensive, multicentre studies are required to validate the clinical utility of CEUS in CRC management.

Gastric Cancer Angiogenesis Assessment by Dynamic Contrast Harmonic Imaging Endoscopic Ultrasound (CHI-EUS) and Immunohistochemical Analysis-A Feasibility Study

Tumor vascular perfusion pattern in gastric cancer (GC) may be an important prognostic factor with therapeutic implications. Non-invasive methods such as dynamic contrast harmonic imaging endoscopic ultrasound (CHI-EUS) may provide details about tumor perfusion and could also lay out another perspective for angiogenesis assessment. Methods: We included 34 patients with GC, adenocarcinoma, with CHI-EUS examinations that were performed before any treatment decision. We analyzed eighty video sequences with a dedicated software for quantitative analysis of the vascular patterns of specific regions of interest (ROI). As a result, time-intensity curve (TIC) along with other derived parameters were automatically generated: peak enhancement (PE), rise time (RT), time to peak (TTP), wash-in perfusion index (WiPI), ROI area, and others. We performed CD105 and CD31 immunostaining to calculate the vascular diameter (vd) and the microvascular density (MVD), and the results were compared with CHI-EUS parameters. Results: High statistical correlations (p < 0.05) were observed between TIC analysis parameters MVD and vd CD31. Strong correlations were also found between tumor grade and 7 CHI-EUS parameters, p < 0.005. Conclusions: GC angiogenesis assessment by CHI-EUS is feasible and may be considered for future studies based on TIC analysis.

Anti-Angiogenic Treatment in Pseudomyxoma Peritonei-Still a Strong Preclinical Rationale

Simple Summary

Patients with pseudomyxoma peritonei that are not cured by the standard treatment (cytoreductive surgery and hyperthermic intraperitoneal chemotherapy) have no efficacious treatment options. Drugs that inhibit formation of new vessels (anti-angiogenic drugs) could be a therapeutic option for these patients. Using patient samples and animal models we show that angiogenesis is important in pseudomyxoma peritonei and that anti-angiogenic drugs may indeed have an effect. Our results support continued efforts to determine the role of anti-angiogenic treatment in pseudomyxoma peritonei.

Abstract

Pseudomyxoma peritonei (PMP) is a rare, slow-growing cancer characterized by progressive accumulation of intraperitoneal mucinous tumor deposits. Cytoreductive surgery and hyperthermic intraperitoneal chemotherapy (HIPEC) cures approximately 50% of patients, but in unresectable and recurrent cases, treatment options are limited. Anti-angiogenic treatment is being explored as a potential therapeutic option. Using PMP patient samples, microvessel densities (immunostaining for CD31 and CD105) and pro-angiogenic factors were analyzed, and the proliferative response upon incubation with human umbilical cord vascular endothelial cells (HUVEC) was determined. Growth inhibition by anti-angiogenic drugs was analyzed in patient-derived xenograft models of PMP. PMP tumor tissues were found to be highly vascularized and contained key pro-angiogenic factors, in particular related to vascular endothelial growth factor (VEGF) signaling, but interestingly, high levels of fibroblast growth factor 2 were also detected. HUVEC proliferation was stimulated upon incubation with fresh tumor samples and the observed proliferation could be inhibited by VEGF pathway inhibitor bevacizumab. In xenograft models the two VEGF pathway inhibitors, bevacizumab and aflibercept, inhibited tumor growth. This work reemphasizes the importance of angiogenesis as a major driver in PMP and strengthens the preclinical rationale for continued exploration of angiogenesis inhibition in the hope of providing novel treatment to a group of patients that have few other treatment options.

Detection of Mice Colorectal Tumors by Endoluminal Ultrasound Biomicroscopic Images and Quantification of Image Augmented Gray Values Following Injection of VEGFR-2 Targeted Contrast Agent

RATIONALE AND OBJECTIVES

Ultrasound biomicroscopy (UBM) is a noninvasive imaging technique that can be applied in detecting colonic tumors and, once associated with an ultrasound contrast agent (UCA), can identify the molecular expression of cancer-related biomarkers, such as the vascular endothelial growth factor receptor 2 (VEGFR-2). The present work aimed to detect colonic tumors and quantify augmented gray values of endoluminal UBM (eUBM) images from colonic tumors following the injection of VEGFR-2 targeted UCA (VEGFR2-UCA) into a mouse model of colorectal cancer.

MATERIAL AND METHODS

A 40 MHz miniprobe catheter inserted through the biopsy channel of a pediatric flexible bronchofiberscope was used to obtain colonoscopic and B-mode eUBM images simultaneously. Seventeen tumor-bearing mice had their colons inspected and six of them were subjected to a VEGFR2-UCA injection to predict VEGFR-2 expression.

RESULTS

All animals developed distal colon tumors and eUBM was able to detect all of them and also to characterize the tumors, with 71.4% being in situ lesions and 28.6% being tumors invading the mucosa + muscularis mucosae + submucosa layers, as confirmed by histopathology. After VEGFR2-UCA injection, gray values from the eUBM tumoral images increased significantly (p < 0.01). Tumor sites with increased eUBM image gray values corresponded to areas with increased VEGFR-2 expression, as confirmed by immunohistochemistry.

CONCLUSION

The results confirm eUBM as a powerful noninvasive and real-time tool for detecting colon tumor and its invasiveness and once associated with VEGFR2-UCA may become a tool for the detection of VEGFR-2 expression in colonic tumors.

Progress in Endoscopic Treatment of Hemorrhoids

Hemorrhoids are one of the most common diseases of the anorectal region. Previously, treatment for hemorrhoids included conservative treatment, outpatient treatment, and surgical treatment. The development of flexible reversible endoscopes has provided precise controllability and imaging, enabling further improvement and development of various endoscopic techniques to treat hemorrhoids. This article discusses several of these endoscopic techniques: rubber band ligation, sclerotherapy, and electrocoagulation. The development, efficacy, and advantages of these treatments are summarized and evaluated. It is expected that going forward, endoscopic technology will be further applied in clinical practice and may become the first-line method for the treatment of hemorrhoids.

Preoperative rectal tumor embolization as an adjunctive tool for bloodless abdominoperineal excision: A case report

BACKGROUND

Abdominoperineal excision (APE)-related hemorrhage can be challenging due to difficult access to pelvic organs and the risk of massive blood loss. The objective of the present study was to demonstrate the use of preoperative embolization (PE) as a strategy for blood preservation in a patient with a large low rectal tumor with a high risk of bleeding, scheduled for APE.

CASE SUMMARY

A 56-year-old man presented to our institution with a one-year history of anal bleeding and rectal tenesmus. The patient was diagnosed with bulky adenocarcinoma limited to the rectum. As the patient refused any clinical treatment, surgery without previous neoadjuvant chemoradiation was indicated. The patient underwent a tumor embolization procedure, two days before surgery performed via the right common femoral artery. The tumor was successfully devascularized and no major bleeding was noted during APE. Postoperative recovery was uneventful and a one-year follow-up showed no signs of recurrence.

CONCLUSION

Therapeutic tumor embolization may play a role in bloodless surgeries and increase surgical and oncologic prognoses. We describe a patient with a bulky low rectal tumor who successfully underwent preoperative embolization and bloodless abdominoperineal resection.

Clinical significance of expression of fibrous sheath interacting protein 1 in colon cancer

BACKGROUND

The occurrence and development of colon cancer are complex, involving a variety of genetic changes, such as mutation and activation of oncogenes, inactivation of tumour suppressor genes, and aberrant proliferation and apoptosis regulation mechanisms. Fibrous sheath interacting protein 1 (FSIP1) is a newly discovered oncogene that is frequently activated in a variety of tumours such as breast cancer and bladder cancer. However, the clinical significance of FSIP1 in colon cancer is unclear. In this study, we analysed the clinical significance of expression of FSIP1 in human colon cancer, aimed to clarify the biological role of FSIP1 in the development and progression of colon cancer.

AIM

To investigate the clinical significance of expression of FSIP1 in colon cancer.

METHODS

From March 2011 to March 2014, 302 specimens of tumour tissues and paracancerous tissues were obtained from patients pathologically diagnosed with colon cancer at Shengjing Hospital of China Medical University. Immunohistochemistry was used to detect FSIP1 expression in colon cancer tissues and adjacent normal tissues. Spearman correlation coefficient and Cox regression analyses were used to determine the relationship between FSIP1 expression and clinicopathological factors and prognosis, as well as the impact on survival.

RESULTS

Compared with its expression in adjacent normal tissues, FSIP1 was expressed at higher levels in colon cancer tissues. Spearman correlation analysis showed that high expression of FSIP1 was positively correlated with clinicopathological stage, lymph node metastasis, and poor prognosis in colon cancer; it was negatively correlated with the degree of tumour differentiation. Cox regression analysis showed that high FSIP1 expression was an independent risk factor for the prognosis of colon cancer patients.

CONCLUSION

High expression of FSIP1 may be one of the important factors affecting the clinical outcome of colon cancer patients and leading to poor prognosis.

KIT and platelet-derived growth factor receptor α wild-type gastrointestinal stromal tumor associated with neurofibromatosis type 1: Two case reports

BACKGROUND

Gastrointestinal stromal tumors (GISTs) associated with neurofibromatosis are uncommon compared to their gastrointestinal counterparts. Patients with neurofibromatosis type 1 (NF-1) have an increased risk of developing gastrointestinal tumors, including rare types such as GIST.

CASE SUMMARY

A 60-year-old male Chinese patient was diagnosed with NF-1 10 years ago and presented with upper abdominal discomfort and black stools. Endoscopic ultrasonography and an enhanced abdominal computed tomography scan revealed a mass located 4 cm from the muscular layer of the descending duodenum. A 59-year-old Chinese woman who was diagnosed with NF-1 25 years ago presented with sudden unconsciousness and black stools. Multiple masses in the duodenum were noted by echogastroscopy and an enhanced abdominal computed tomography scan. Both patients presented with cutaneous neurofibromas. The histologic examination of tumors from both patients revealed spindle cells and low mitotic activity. Immunohistochemically, the tumor cells showed strong positivity for KIT (CD117), DOG-1, CD34, and Dehydrogenase Complex Subunit B, and negativity for SMA, desmin, S-100, and β-catenin. None of the six tumors from two patients had KIT exon 9, 11, 13, or 17 or platelet-derived growth factor receptor α exon 12 or 18 mutation, which is a typical finding for sporadic GISTs. None of the six tumors from the two patients had a BRAFV600E mutation. The patients were alive and well during the follow-up period (range: 0.6-5 yr).

CONCLUSION

There have been only a few previous reports of GISTs associated with NF-1. Although GISTs associated with NF-1 have morphologic and immunohistochemical similarities with GISTs, the pathogenesis, incidence, genetic background, and prognosis are not completely known. A medical history of NF-1 in a patient who has gastrointestinal bleeding or anemia and an intra-abdominal mass with nonspecific computed tomography features may help in diagnosing GIST by virtue of the well-known association of these two entities. Molecular genetic studies of cases indicated that GISTs in NF-1 patients have a different pathogenesis than sporadic GISTs.

Dysregulated KDR and FLT1 Gene Expression in Colorectal Cancer Patients

BACKGROUND

Colorectal cancer (CRC) is one of the most commonly-diagnosed malignancies throughout the world and the fourth-leading cause of cancer deaths globally. Angiogenesis and the resultant tumor neovascularization is a well-known cancer hallmark. Here we investigated the expression of FLT1 and KDR, the influential genes in angiogenesis regulation, in CRC patients.

METHODS

We assessed FLT1 and KDR mRNA expression in 47 CRC samples and matched adjacent noncancerous tissues (ANCT) by quantitative real-time PCR. The Spearmen correlation coefficient and receiver operating characteristic (ROC) curves were also examined.

RESULTS

Both genes were expressed at significantly greater levels in CRC tissues than in ANCT (p < 0.05). A significant association was found between KDR expression and disease stage and lymph status in CRC patients. Furthermore, the Spearman correlation demonstrated a moderate correlation between FLT1 and KDR expression in CRC samples. Finally, ROC curve analysis demonstrated that FLT1 had the greatest sensitivity (85.1%), while the greatest specificity was achieved by a combination of the two genes.

CONCLUSION

The dysregulated FLT1 and KDR expression, in addition to the observed correlation and ROC curve results, indicate the critical importance of angiogenesis among the cancer pathways in CRC. These data can broaden our current knowledge of angiogenesis in CRC to improve disease diagnosis and patient treatment.

Contrast enhanced ultrasound imaging by nature-inspired ultrastable echogenic nanobubbles

Advancement of ultrasound molecular imaging applications requires not only a reduction in size of the ultrasound contrast agents (UCAs) but also a significant improvement in the in vivo stability of the shell-stabilized gas bubble. The transition from first generation to second generation UCAs was marked by an advancement in stability as air was replaced by a hydrophobic gas, such as perfluoropropane and sulfur hexafluoride. Further improvement can be realized by focusing on how well the UCAs shell can retain the encapsulated gas under extreme mechanical deformations. Here we report the next generation of UCAs for which we engineered the shell structure to impart much better stability under repeated prolonged oscillation due to ultrasound, and large changes in shear and turbulence as it circulates within the body. By adapting an architecture with two layers of contrasting elastic properties similar to bacterial cell envelopes, our ultrastable nanobubbles (NBs) withstand continuous in vitro exposure to ultrasound with minimal signal decay and have a significant delay on the onset of in vivo signal decay in kidney, liver, and tumor. Development of ultrastable NBs can potentially expand the role of ultrasound in molecular imaging, theranostics, and drug delivery.

shRNA-interfering LSD1 inhibits proliferation and invasion of gastric cancer cells via VEGF-C/PI3K/AKT signaling pathway

BACKGROUND

Histone Lysine Specific Demethylase 1 (LSD1) is the first histone demethylase to be discovered, which regulates various biological functions by making lysine of histone H3K4, H3K9 and non-histone substrates demethylated. Abnormal regulation of LSD1 is closely related to the occurrence and development of gastric cancer. The change of LSD1 expression level plays an important role in the proliferation and metastasis of gastric cancer cells. The study of its function and mechanism may provide a theoretical basis for early diagnosis and targeted therapy of gastric cancer.

AIM

To investigate the effect of downregulation of lysine-specific demethylase 1 (LSD1) expression on proliferation and invasion of gastric cancer cells and the possible regulatory mechanisms of the VEGF-C/PI3K/AKT signaling pathway.

METHODS

The LSD1-specific short hairpin RNA (shRNA) interference plasmid was transiently transfected, and expression of LSD1 was downregulated. The cell proliferation ability of LSD1 was observed by CCK-8 assay after downregulating expression of LSD1. Transwell invasion assay was used to observe the change of cell invasion ability after downregulating expression of LSD1. Expression of phosphorylated phosphoinositide 3-kinase (p-PI3K), PI3K, p-AKT, AKT, vascular endothelial growth factor receptor (VEGFR)-3, matrix metalloproteinase (MMP)-2 and MMP-9 in each group was detected by Western blotting.

RESULTS

The cell proliferation ability of transiently transfected LSD1-shRNA interference plasmid group was significantly lower than that of the control group (P < 0.05). Transwell invasion assay showed that the number of cells across the membrane of the LSD1-shRNA transfection group (238.451 ± 5.216) was significantly lower than that of the control group (49.268 ± 6.984) (P < 0.01). Western blotting showed that expression level of VEGF-C, p-PI3K, PI3K, p-AKT, AKT, VEGFR-3, MMP-2 and MMP-9 in the LSD1-shRNA group was significantly lower than that in the control group (P < 0.05).

CONCLUSION

Downregulation of LSD1 expression inhibits metastatic potential of gastric cancer cells, and VEGF-C-mediated activation of PI3K/AKT signaling pathway, which may be an important mechanism for inhibiting lymph node metastasis in gastric cancer cells.

Clinicopathological significance of human leukocyte antigen F-associated transcript 10 expression in colorectal cancer

BACKGROUND

Colorectal cancer (CRC) is a common malignancy of the gastrointestinal tract. The worldwide mortality rate of CRC is about one half of its morbidity. Ubiquitin is a key regulatory factor in the cell cycle and widely exists in eukaryotes. Human leukocyte antigen F-associated transcript 10 (FAT10), known as diubiquitin, is an 18 kDa protein with 29% and 36% homology with the N and C termini of ubiquitin. The function of FAT10 has not been fully elucidated, and some studies have shown that it plays an important role in various cell processes.

AIM

To examine FAT10 expression and to analyze the relationship between FAT10 expression and the clinicopathological parameters of CRC.

METHODS

FAT10 expression in 61 cases of CRC and para-cancer colorectal tissues was measured by immunohistochemistry and Western blotting. The relationship between FAT10 expression and clinicopathological parameters of CRC was statistically analyzed.

RESULTS

Immunohistochemical analysis showed that the positive rate of FAT10 expression in CRC (63.93%) was significantly higher than that in tumor-adjacent tissues (9.84%, P < 0.05) and normal colorectal mucosal tissue (1.64%, P < 0.05). Western blotting also indicated that FAT10 expression was significantly higher in CRC than in tumor-adjacent tissue (P < 0.05). FAT10 expression was closely associated with clinical stage and lymphatic spread of CRC. FAT10 expression also positively correlated with p53 expression.

CONCLUSION

FAT10 expression is highly upregulated in CRC. FAT10 expression is closely associated with clinical stage and lymphatic spread of CRC.

Hedyotis diffusa willd extract suppresses colorectal cancer growth through multiple cellular pathways

The development of colorectal cancer (CRC) is strongly associated with the imbalance of various intracellular signal transduction cascades, including protein kinase B (AKT), mitogen-activated protein kinase 1 (MAPK), signal transducer and activator of transcription 3 (STAT3), as well as crosstalk between these signaling networks. At present, anti-tumor agents are often single-targeted and therefore are not always therapeutically effective. Moreover, long-term use of these anti-tumor agents often generates drug resistance and potential side effects. These problems highlight the urgent need for the development of novel and more effective anti-cancer drugs. Hedyotis diffusa Willd (HDW) has been used as a major component in traditional Chinese medicine for the clinical treatment of colorectal cancer, with a limited number of adverse effects. However, the molecular mechanisms, which underlie its anti-cancer activity, still require further elucidation. In the present study, using xenograft models and various different human CRC cell lines, the efficacy of the ethanol extract of HDW (EEHDW) against tumor growth was evaluated, and its underlying molecular mechanisms of action were investigated. It was demonstrated that EEHDW was able to inhibit cancer growth in vivo and in vitro. Furthermore, EEHDW was able to suppress the activation of several CRC-associated signaling pathways and was able to regulate the expression of various inflammatory and angiogenic factors. This resulted in the induction of apoptosis and inhibition of cellular proliferation, as well as tumor angiogenesis. The present study demonstrated that EEHDW is able to exhibit anti-cancer activity due to its ability to affect multiple intracellular targets, which suggests that it may be a novel multi-potent therapeutic agent for the treatment of colorectal cancer.