Yu Hua Quan

Thoracoscopic Color and Fluorescence Imaging System for Sentinel Lymph Node Mapping in Porcine Lung Using Indocyanine Green-Neomannosyl Human Serum Albumin: Intraoperative Image-Guided Sentinel Nodes Navigation

PurposeThis study was performed to validate a newly developed sentinel lymph node (SLN) targeting tracer, indocyanine green-neomannosyl human serum albumin (ICG:MSA), and a thoracoscopic version of the intraoperative color and fluorescence imaging system (ICFIS) for lung cancer SLN mapping.MethodsICG alone or ICG:MSA (5xa0μg/kg) was injected into the rat thigh, and the results were compared. The fluorescence signal-to-background ratios of SLNs were recorded and evaluated over a 2-h period by using ICFIS. Additionally, a SLN biopsy was performed via video-assisted thoracoscopic surgery with the use of ICG:MSA in porcine lung by using thoracoscopic ICFIS.ResultsThe newly developed ICG:MSA showed a significantly improved signal-to-background ratio compared with ICG alone throughout the trials. All SLNs were identified in both rats (ten SLNs in ten rat thighs) and pigs (ten SLNs in ten porcine lungs) under in vivo conditions. All SLNs were dissected successfully by using video-assisted thoracoscopic surgery with the help of thoracoscopic ICFIS.DiscussionICG:MSA accumulates in the SLN by uptake and retention through the mannose-specific receptors on macrophages. Thoracoscopic ICFIS successfully assisted SLN mapping despite low near-infrared light transmission in the commercial thoracoscope. On the basis of the results of the thoracoscopic SLN mapping, we anticipate that ICG:MSA and thoracoscopic ICFIS can be translated to clinical trials in the near future.

Highly sensitive and selective anticancer effect by conjugated HA-cisplatin in non-small cell lung cancer overexpressed with CD44

ABSTRACT In spite of severe side effects, chemotherapy is widely used as a major anticancer treatment in non-small cell lung cancer (NSCLC). In order to enhance the therapeutic properties and reduce side effects, enormous efforts have been devoted to direct anticancer agents specifically to tumor tissues by the use of nanoparticles, or cancer cell marker attached drugs. However, cell-specific chemotherapy is still in its infancy and is not applicable to all types of cancers due to the complexity of the cancer occurrence and progress. In this study, we demonstrate that hyaluronan (HA)-conjugated cisplatin has highly selective and sensitive anticancer effects in NSCLC cells that overexpress the trans-membrane receptor, CD44, as HA is a specific ligand for CD44. In proliferation experiments, HA-conjugated cisplatin showed dramatic cell viability decreases (from 100% to 42.31%) in H1299 cells, which overexpress CD44, whereas no such change was observed in A549 and HFL1, which have little to no expression of CD44. More importantly, conjugation with HA decreased the dosage concentration of cisplatin by 50-fold for both cytotoxic and anti-metastatic effects. In addition, HA-cisplatin conjugate treatment selectively decreased migration (from 100% to 7.8%) and invasiveness (from 100% to 21.4%, respectively) of H1299. Based on our experimental results, we strongly believe that HA-cisplatin conjugate is a potential anticancer chemo-agent, which target CD44 overexpression in NSCLC, with minimal side effects and high therapeutic properties.

The effects of sonic hedgehog signaling pathway components on non-small-cell lung cancer progression and clinical outcome

BackgroundResearchers in recent studies have reported that the sonic hedgehog (Shh) signaling pathway plays a crucial role during tumorigenesis, angiogenesis and cellular differentiation. We investigated the clinical and pathological significances of the Shh pathway and of its lymphangiogenic components in non-small-cell lung cancer (NSCLC), namely, Shh, glioma-associated oncogene homolog zinc finger protein 1 (Gli1), lymphatic vessel endothelial hyaluronan receptor 1 (LYVE-1) and vascular endothelial growth factor D (VEGF-D).MethodsThe expression of Shh, Gli1, LYVE-1 and VEGF-D in primary NSCLC tissue from 40 patients was examined using immunohistochemical assays, and relationships between expression and clinicopathological data, such as age, gender, histology, tumor size, nodal stage, visceral pleural invasion, lymphatic thromboembolism, recurrence and overall survival were investigated.ResultsOf the 40 specimens examined, 25 (62.5%), 20 (50.0%), 11 (27.5%) and 20 (50.0%) were positive for Shh, Gli1, LYVE-1 or VEGF-D expression, respectively. The expression of Gli1 and LYVE-1 were significantly associated (Pu2009=u20090.011), and Shh and LYVE-1 expression was related to visceral pleural invasion and lymphatic thromboembolism, respectively (Pu2009<u20090.05). Shh expression levels compared on survival curves were statistically significant in univariate logrank analysis (Pu2009=u20090.020). However, other clinicopathological factors did not reveal any statistical significance in univariate and multivariate analyses.ConclusionsTo our knowledge, this the first report of the relationship between components of the Shh signaling pathway and prognosis in NSCLC. The expression of Shh, Gli1 and LYVE-1 was found to be associated with clinicopathological factors and survival. Thus, the overexpression of the Shh signaling pathway could serve as a predictor of malignant behavior, including lymphangiogenesis, in NSCLC.

Intraoperative pulmonary neoplasm identification using near-infrared fluorescence imaging.

OBJECTIVESnNear-infrared (NIR) fluorescence imaging provides surgeons with real-time visual information during surgery. The purpose of this pilot trial was to evaluate the safety and feasibility of the intraoperative detection of pulmonary neoplasms with NIR fluorescence imaging after low-dose indocyanine green (ICG) injection.nnnMETHODSnEleven consecutive patients who were scheduled to undergo resection of pulmonary neoplasms were enrolled in this study. ICG (1 mg/kg) was administered intravenously 1 day before surgery, and the retrieved surgical specimens were examined for fluorescence signalling by using NIR fluorescence imaging system on a back table in the operating room. We analysed the fluorescence intensity, pathology, size, depth from the pleural surface and metabolic activity of the pulmonary neoplasms.nnnRESULTSnFluorescence signalling was detected in all specimens except in one from a patient with primary lung cancer. Two false-positive cases that presented no residual tumour with obstructive pneumonitis, after concurrent chemoradiation therapy for primary lung cancer before the operation, were identified, and their fluorescence intensity was 8.6 ± 0.4. The mean fluorescence intensity of the eight pulmonary tumours was 3.4 ± 1.9, and these tumours did not differ in pathology, size, depth from the pleural surface or metabolic activity.nnnCONCLUSIONSnNIR fluorescence imaging could safely identify pulmonary neoplasms after the systemic injection of ICG. In addition, low-dose ICG is sufficient for NIR fluorescence imaging of pulmonary neoplasms. However, because the passive accumulation of ICG could not be used to discriminate tumours with inflammation, tumour-targeted fluorescence should be developed to solve this problem in the future.

Intraoperative combined color and fluorescent images–based sentinel node mapping in the porcine lung: Comparison of indocyanine green with or without albumin premixing

OBJECTIVESnWe developed a multimodal optical imaging system for intraoperative visualization of sentinel lymph nodes (SLNs). This study is to validate our system by showing SLNs in the lung through combined optical color and fluorescent image with indocyanine green (ICG) and ICG with human serum albumin (HSA).nnnMETHODSnIdentical ICG concentrations of ICG only or ICG:HSA was injected into the rat footpad and porcine lung. Absolute amounts of the fluorescents were scaled on the basis of animal weights. The entire procedures were recorded using color and near-infrared (NIR) charge-coupled device (CCD) cameras simultaneously, and the 2 images were merged by real-time image processing software. All fluorescence intensity signals to background ratio (SBR) and retention rates at SLN for both fluorescents were estimated and compared.nnnRESULTSnThis newly developed intraoperative color and fluorescence optical imaging system successfully visualized the SLNs in animal experiments. The SLNs were identified 100% for both rat and pig under inxa0vivo conditions. Real-time image processing software overcame the low signal of NIR fluorescence images. ICG and ICG:HSA provided no significantly different SBR in the SLN images for both rat thigh and pig lung.nnnCONCLUSIONSnThe intraoperative optical imaging system enabled real-time image-guided surgery during SLN mapping in lung in an animal model. The ICG retention rate was similar to ICG:HSA. ICG alone can be useful for SLN imaging during lung cancer surgery.

Intraoperative fluorescence image-guided pulmonary segmentectomy

BACKGROUNDnThe intraoperative color and fluorescence-merged imaging system (ICFIS) is a new technology that may aid the demarcation of intersegmental borders during pulmonary segmentectomy. This study was performed to validate, for the first time, image-guided segmentectomy using ICFIS and to find the optimal dosage of fluorescent dye to ensure safe and sustained imaging during surgery.nnnMETHODSnNine rabbits were subjected to pulmonary segmentectomy. These constituted three groups of three rabbits each. After ligation of the segmental pulmonary artery supplying the targeted segment, the rabbits were injected intravenously with indocyanine green (ICG) at a concentration of 0.3, 0.6, or 3.0 mg/kg, depending on their group assignment. The optimal dose was determined from the rabbit study and then used to guide ICFIS during pulmonary segmentectomy in five pigs.nnnRESULTSnThe fluorescent signal contrast ratios of the targeted area to the normal lung using ICG concentrations of 0.3, 0.6, or 3.0 mg/kg were 1.9 ± 0.25, 2.0 ± 0.17, and 2.1 ± 0.06, respectively. The mean ICG washout times were 1, 3, and 6 min, respectively. Proceeding with an ICG concentration of 0.6 mg/kg, the mean washout time was found to be longer in pigs (15 min). This provided adequate time for successful ICFIS-guided segmentectomy in all five pigs, without the requirement for additional procedures for intersegmental plane demarcation.nnnCONCLUSIONSnICG image-guided segmentectomy using ICFIS enabled immediate visualization of the intersegmental planes. The washout time using the ICG dose determined in this study was long enough to ensure that visualization was sustained throughout the surgery.

Macrophage-Targeted Indocyanine Green-Neomannosyl Human Serum Albumin for Intraoperative Sentinel Lymph Node Mapping in Porcine Esophagus

BACKGROUNDnThe sentinel lymph node (SLN) concept has been proposed to avoid unnecessary invasive LN dissection in surgery for esophageal cancer. This study evaluated a new macrophage-targeting fluorescent agent, indocyanine green-neomannosyl human serum albumin (ICG:MSA), for SLN mapping using a custom-made intraoperative color and fluorescence-merged imaging system (ICFIS) in porcine esophagus.nnnMETHODSnThe LN targeting ability of ICG:MSA, indocyanine green-human serum albumin (ICG:HSA), and ICG was examined inxa0vitro using the U937 differentiated monocyte cell line and inxa0vivo in a mouse footpad model using fluorescence imaging. SLN identification in rabbit esophagus was then performed using ICG:MSA, ICG:HSA, and ICG. Finally, intraoperative SLN detection was conducted in porcine esophagus after esophagoscopic injection of ICG:MSA.nnnRESULTSnThe fluorescence signal of U937 cells treated by ICG:MSA was significantly higher than that of ICG or ICG:HSA (ICG: 1.0 ± 0.37; ICG:HSA: 3.4 ± 0.28, ICG:MSA: 6.8 ± 1.61; ICG to ICG:HSA, pxa0= 0.03; ICG:HSA to ICG:MSA, pxa0= 0.04; ICG to ICG:MSA, pxa0= 0.0009). ICG:MSA was retained in popliteal LNs as long as 3 h, while ICG rapidly diffused through the entire mouse lymphatic system within 5 min. Esophageal SLN was detected within 15 min after injection of either ICG or ICG:MSA, but ICG:MSA provided more distinguishable images of LNss than ICG in rabbit esophagus. The SLN was also successfully detected in all porcine esophagus; the mean number of SLNs identified per esophagus was 1.6 ± 0.55.nnnCONCLUSIONSnICG:MSA has more specific macrophage-targeting properties, which could overcome the limitation of the low SLN retention of ICG, and could provide more precise real-time SLN detection during esophageal cancer surgery.

Endoscopic sentinel lymph node biopsy using indocyanine green-neomannosyl human serum albumin: Endoscopic Sentinel Lymph Node Biopsy

The aim of this study was to determine the possibility of endoscopic sentinel lymph node biopsy of the head and neck region using indocyanine green‐neomannosyl human serum albumin (ICG:MSA) and a custom‐made intraoperative color‐and‐fluorescence‐merged imaging system (ICFIS).

Fluorescent image-based evaluation of gastric conduit perfusion in a preclinical ischemia model

BackgroundnThis study evaluated near-infrared (NIR) fluorescent images to assess gastric conduit perfusion after an esophagectomy in a porcine model of gastric conduit ischemia. The time necessary to acquire a sufficient fluorescent signal to confirm ischemia in the gastric conduit after peripheral or central venous injection of indocyanine green (ICG) was also investigated.nnnMethodsnA reversible gastric conduit ischemic pig model was established through ligation and release of the right gastroepiploic artery (RGEA, n=10). The esophageal reconstruction was performed to create an esophagogastric anastomosis. After ligation of the RGEA, ICG was injected into an ear vein (n=6) or the inferior vena cava (n=4). Under fluorescent imaging system guidance, the fluorescent signal-to-background ratio (SBR) in the gastric conduit or esophagus was measured during the entire procedure. We estimated the time necessary to acquire fluorescent signals in the gastric conduit using two different injection routes.nnnResultsnWhen the RGEA was ligated, the SBR in the esophagus was significantly higher than that in the gastric conduit (P=0.02), and the SBR in the gastric conduit recovered within 180 s after release of the ligation. The time to acquire a fluorescent signal was faster with a central route than with a peripheral route (P=0.04).nnnConclusionsnWe successfully created an ischemic animal model of the gastric conduit. Using this animal model, we evaluated the sensitivity and applicability of the fluorescent imaging system for observation and identification of ischemic areas during an esophagectomy.

Real-time computed tomography fluoroscopy-guided solitary lung tumor model in a rabbit

Preclinical studies of lung cancer require suitable large-animal models to allow evaluation and development of surgical and interventional techniques. We assessed the feasibility and safety of a novel rabbit lung cancer model of solitary tumors, in which real-time computed tomography fluoroscopy is used to guide inoculation of VX2 carcinoma single-cell suspensions. Thirty-eight rabbits were divided into four groups according to the volume of the VX2 tissue or cell suspension, the volume of lipiodol, the volume of Matrigel, and the injection needle size. The mixtures were percutaneously injected into rabbit lungs under real-time computed tomography fluoroscopy guidance. Two weeks later, VX2 lung carcinomas were confirmed via positron emission tomography/computed tomography, necropsy, and histology. Real-time computed tomography fluoroscopy allowed the precise inoculation of the tumor cell suspensions containing lipiodol, while the use of Matrigel and a small needle prevented leakage of the suspensions into the lung parenchyma. Solitary lung tumors were successfully established in rabbits (n = 22) inoculated with single-cell suspensions (150 μL), lipiodol (150 μL), and Matrigel (150 μL) using a 26-gauge needle. This combination was determined to be optimal. Pneumothorax was observed in only two of the 38 rabbits (5.3%), both of which survived to the end of the study without any intervention. Real-time computed tomography fluoroscopy-guided inoculation of VX2 single-cell suspensions with lipiodol and Matrigel using a small needle is an easy and safe method to establish solitary lung tumors in rabbits.