Xanthene-based Hg2+ fluorescent probe for detection of Hg2+ in water/food samples, as well as imaging of live cells, zebrafish and tobacco seedlings

In this paper, an Hg2+ detection probe, HOS, was prepared with a xanthene as the parent fluorophore. Hg2+-initiated thioacetal deprotection reaction is the detection mechanism of this probe. After testing, the probe HOS was able to accurately determine Hg2+ with a detection limit of 36 nM. It was successfully applied to the detection of Hg2+ in different water samples and shrimp samples, meanwhile, the filter paper strips prepared by HOS were obviously changed from light yellow to dark yellow under daylight, and from green to yellow under 365 nm UV light. Furthermore, probe HOS enabled Hg2+ bioimaging experiments on HepG2 cells, zebrafish and tobacco seedlings under laser confocal microscopy.

Voxel Based Analysis of Local Dose Patterns on Radiation Induced Xerostomia in Head and Neck Cancer with Machine Learning Methods

PURPOSE/OBJECTIVE(S)

Despite the technological advancements, xerostomia caused by the irradiation of parotid and/or submandibular glands significantly impacts a patient's quality of life and remains a clinical challenge. The mean dose within the salivary glands that neglects the local dose effect is an oversimplified predictor thus its efficacy is severely limited. This study aims to uncover the local dose patterns associated with the xerostomia by performing a voxel-based analysis of the spatial parotid dose.

MATERIALS/METHODS

A cohort of 143 patients who underwent intensity modulated radiation therapy treatment were retrospectively selected for this study. A binary classification was adopted for predictive modeling: group 1 (102 patients) if grade 0 or 1 and group 2 (41 patients) if grade 2 or 3. The anatomy of the parotid gland from the computed tomography (CT) of these patients were standardized to that of a reference patient with rigid and multistage B-spline deformable registration. The resultant deformation field vectors were subsequently utilized to warp the parotid doses and dose gradients to the reference ones. To facilitate pattern recognition, the bilateral parotid doses and dose gradients were further regrouped into contra- and ipsi-lateral depending on their proximity to the tumor targets. Four supervised machine learning (ML) models including ReliefF, L1 regularized logistic regression (L1LR), ridge regression (RR), and random forest (RF) were employed to determine the feature importance of each voxel and discover the dose patterns within the glands that are correlated with xerostomia. The predictive performance of each model was evaluated with the area under the curves (AUC) of the receiver operating characteristic.

RESULTS

The image registration accuracy of an average of 95.6% for the parotid gland standardization on CT images was achieved. The four ML models were assessed with 10-fold cross validation showing comparable performance and the AUC scores were 0.74 ± 0.09, 0.75 ± 0.08, 0.73 ± 0.10, and 0.77 ± 0.09 for ReliefF, L1LR, RR, and RF, respectively. The importance patterns showed that the doses to the superior and medial region of the contralateral parotid gland were more correlated with xerostomia from the ReliefF model but not others. Similar importance patterns were observed from the dose gradient distributions along the left-right and anterior-posterior directions.

CONCLUSION

The voxel-based model, which takes into account the spatial information of dose and dose gradient within the parotid gland, demonstrated an improvement in xerostomia predictive modeling as compared to the mean dose predictor, particularly in the local dose effect on xerostomia. If these findings are validated with more patient data and independent studies, they could be incorporated into treatment planning of head and neck patients to reduce the toxicity occurrence.

Risk factors of bone metastasis in patients with newly diagnosed prostate cancer

OBJECTIVE

The current study aimed to explore the risk factors for bone metastasis (BMT) in patients with newly diagnosed prostate cancer (PCa).

PATIENTS AND METHODS

The clinical data of 322 patients newly diagnosed with PCa following transrectal prostate biopsy at our hospital from October 2016 to March 2021 were analyzed. According to the results of whole-body bone emission computed tomography (ECT) scanning, patients were divided into the following two groups: bone metastasis group (BMT) and none-bone metastasis group (None-BMT). Univariate and multivariate logistic regression analyses were performed to assess the BMT-related factors associated with PCa. A receiver operating characteristic curve was also used to compare the diagnostic value of total prostate-specific antigen (TPSA), prostate-specific antigen density (PSAD), Gleason score and alkaline phosphatase (ALP) for prostate cancer bone metastasis (PCBM).

RESULTS

The results revealed that the incidence of BMT in newly diagnosed patients with PCa was ~22.05% (71/322). Univariate analysis demonstrated that Gleason score, clinical T stage, TPSA, PSAD and ALP were associated with PCBM (p<0.001). Furthermore, the results of multivariate regression analysis revealed that TPSA, PSAD, Gleason score and ALP were independent risk factors for BMT (p <0.05). The cutoff values for TPSA, PSAD, ALP and Gleason score were 39.58 ng/ml, 1.489 ng/(ml/cm3), 93.15 U/l and 7.5, respectively. Additionally, the respective sensitivities for TPSA, PSAD, ALP and Gleason score were 67.6, 62.0, 57.7 and 46.5%, and the respective specificities were 88.4, 98.0, 100 and 98.8%.

CONCLUSIONS

The current study determined that TPSA, PSAD, Gleason score and ALP were predictors of PCBM. In patients with PSA levels >39.58 ng/ml, PSAD levels >1.489 ng/(ml/cm3), Gleason scores >7.5 and ALP levels >91.0 U/l, a whole-body bone ECT scan is recommended.

Vertebral Fractures Following Stereotactic Body Radiotherapy for Spine Oligometastases: A Multi-institutional Analysis of Patient Outcomes

AIMS

Stereotactic body radiotherapy (SBRT) is a locally ablative therapy used for the treatment of patients with spine metastases. However, it is associated with higher rates of vertebral compression fractures (VCF) than conventionally fractionated palliative radiotherapy. The purpose of this study was to determine the rate of VCF following spine SBRT and to identify the risk factors associated with this outcome.

MATERIALS AND METHODS

We retrospectively reviewed patients treated at two Australian institutions from January 2015 to March 2019. Descriptive statistics were used to assess patient, tumour and treatment factors. The Log-rank test and Cox proportional hazards model were applied in univariate and multivariable analyses to identify factors associated with VCF, local control and overall survival.

RESULTS

We evaluated 113 spinal segments from 84 patients, with a median follow-up time of 11.9 months. The median dose and fractionation utilised was 30 Gy in three fractions (67.3%), with a single-fraction rate of 0.9%. The median Spinal Instability Neoplastic Score (SINS) of the lesions was 4/18, with most (84.1%) being SINS stable, scoring between 0 and 6. Five VCFs were observed (three progression of pre-existing fractures and two de novo), a cumulative VCF risk of 4.4%. Four of five fractures occurred within the first year after treatment, with a median time to VCF of 9.2 months. A pre-existing VCF (P = 0.011) was associated with subsequent fracture on multivariable analysis, whereas all VCF segments displayed lytic disease appearance. All fractures were managed conservatively with analgesia, without requirement for subsequent surgical intervention.

CONCLUSION

SBRT to spine metastases is safe with respect to VCF, with rates around the lower limit observed in similar studies. Knowledge of factors that predispose to post-treatment fracture, such as pre-existing compression, lytic vertebral disease and SINS >6 will aid in the counselling and selection of patients for this therapy.

Modifications of Membrane Phospholipids in Response to Extended Aging from Pork Loins

ObjectivesIt is well established that fresh meat shelf-life deteriorates during aging process. We hypothesize that part of the shelf-life reduction is due to membrane phospholipid deterioration through phospholipase activity and/or phospholipid oxidation during aging. Therefore, the objective of this study was to characterize the modifications/deterioration of phospholipid classes/species in pork loins from 3 different aging periods.Materials and MethodsLoins from 20 carcasses were collected at a commercial harvest facility in the Midwest 1 d postmortem from carcasses of Duroc sired crossbred pigs. Four chops from each carcass containing only the longissimus muscle were vacuum packaged and aged at 4°C for 1, 8, and 21 d. A sensitive approach based on electrospray ionization tandem mass spectrometry was used to comprehensively analyze phospholipid composition using the lipid extract from each sample at each aging period (n = 60). Unsaturation index (UI; measurement of the number of double bonds) for each phospholipid species class was also calculated to quantify fatty acyl chain unsaturation for each sample in each aging period.ResultsTotal phospholipid quantity in pork loins was not different between 1d and 8d aged chops but decreased significantly from 8d to 21d of aging (806.6 vs. 297.5 nmol phospholipid/mg lipid; P < 0.01). On the other hand, the mol% data (distribution of each phospholipid species in relative % of total phospholipid) revealed that phosphatidylinositol (PI) and phosphatidylserine (PS) increased in mol% from 1d to 21d of aging in pork loins (P < 0.01). This increase was mainly due to the increase of PI 38:4 (primarily 18:0/20:4) and PS 36:2 (primarily 18:0/18:2) between 1d and 21d samples (P < 0.01). The results showed that phospholipid degradation products like lysophosphatidylcholine (LPC) mol% rose quickly after short term aging (8d) but remained constant through the rest of the 21d aging period (P < 0.01). Conversely, lysophosphatidylethanolamine (LPE) was unaltered between 1d and 8d of aging but decreased between 8d and 21d aged pork loins (P < 0.01). The mol% of phosphatidic acid (PA) also increased between 1d and 21d aged pork loins (P < 0.05). Extended aging did not alter the mol% of total phosphatidylcholine (PC), ether-linked PC (ePC), sphingomyelin (SM), phosphatidylethanolamine (PE) or ether-linked PE (ePE; P > 0.05). Surprisingly, UI revealed the exact opposite trend as the mol% data. The UI of PI and PS decreased (P < 0.01) from 1d to 21 d of aging in pork loins due to the disappearance of many minor PI and PS species with very long chain fatty acids and multiple double bonds such as PI 42:10 and PS 44:10. There was also a slight increase of PC UI after 8 d of aging in pork loins (P < 0.01). The UI for LPC, ePC, SM, LPE, PE, ePE and total phospholipid were not altered in any of the aging periods (P > 0.05).ConclusionThese results confirmed our hypothesis that phospholipids undergo extensive degradation during aging. The data also indicated that the majority of phospholipids in pork loins may maintain integrity over short period aging (1–8d). Among the phospholipid classes, PI and PS were slightly more resistant to deterioration compared with the others due to their ability to modify fatty acyl chain saturation. Additional investigations are necessary to define the role of phospholipid modifications in fresh pork shelf-life and flavor.

Evaluation of Beef Top Sirloin Steaks of Four Quality Grades Cooked to Three Degrees of Doneness

ObjectivesThe objective of this study was to evaluate the impact of quality grade on beef eating quality of top sirloin steaks when cooked to multiple degrees of doneness (DOD).Materials and MethodsBeef top sirloin butts (IMPS #184; N = 60; 15/quality grade) were collected to equally represent 4 quality grades [Prime, Top Choice (Modest and Moderate marbling), Low Choice, and Select]. Top butts were cut into six consecutive steaks, and then divided laterally to get a total of twelve steaks per top butt. Steaks were assigned to one of three DOD: rare (60°C), medium (71°C), and well-done (77°C). Steaks within each DOD were assigned to consumer sensory analysis, trained sensory analysis, fat and moisture analysis, and Warner-Bratzler shear force (WBSF). Consumers (N = 236) were fed samples under red lighting and evaluated steaks for juiciness, tenderness, flavor, and overall liking on continuous line scales. Trained sensory panelists evaluated samples for initial and sustained juiciness, myofibrillar and overall tenderness, connective tissue amount, beef flavor intensity, and off flavor intensity on similar continuous line scales. Data were analyzed as a split-plot, with a whole plot factor of quality grade, and sub-plot factor of DOD.ResultsThere were no interactions (P > 0.05) for all consumer ratings of palatability traits. For quality grade, no differences (P > 0.05) were observed for consumer ratings of tenderness, flavor, and overall liking; however, there was a significant effect (P = 0.01) on juiciness. Prime top sirloin steaks had higher (P < 0.05) juiciness ratings than all other quality grades, except for Top Choice. Additionally, as DOD increased, consumer ratings and the percentage of steaks rated acceptable for all palatability traits decreased (P < 0.05; rare > medium > well-done). There was a quality grade × DOD interaction (P < 0.05) for trained sensory ratings of myofibrillar tenderness, initial juiciness, and sustained juiciness. When steaks were cooked to medium, Prime and Top Choice steaks had higher (P < 0.05) panelist ratings for initial and sustained juiciness than Low Choice and Select steaks. Similar to trained panelist ratings of juiciness, Prime and Top Choice steaks had higher (P < 0.05) ratings of myofibrillar tenderness than Select steaks. Prime and Top Choice steaks had similar (P > 0.05) and higher (P < 0.05) ratings for myofibrillar tenderness when compared to Low Choice steaks. Within DOD, each successive increase in DOD resulted in a concurrent decrease (P < 0.05; rare > medium > well) in trained panelist ratings of myofibrillar tenderness, initial juiciness, and sustained juiciness. There was no quality grade by DOD interactions (P > 0.05) for Warner-Bratzler shear force. Prime steaks were more (P < 0.05) tender than Low Choice and Select steaks but were similar (P > 0.05) to Top Choice. Moreover, as DOD increased, WBSF concurrently increased (P < 0.05; well-done > medium > rare), with well-done steaks having WBSF values 0.8 kg tougher than rare steaks.ConclusionThese results indicate that regardless of DOD, quality grade had minimal impact on the palatability of beef top sirloin steaks. Therefore, unless cooked to a medium DOD, it is unnecessary for consumers, retailers, and foodservice to pay premium prices for higher quality top sirloin steaks, as the same eating experience will be provided.

The Use of Bioelectrical Impedance to Assess Shelf-Life of Beef Longissimus Dorsi

ObjectivesTo evaluate quality attributes of beef longissimus dorsi (LD) during 15 d of simulated retail display using surface and internal bioelectrical impedance analysis (BIA) measurement techniques.Materials and MethodsThe experiment was designed as a split-plot with loin as the whole-plot and pairekd steaks as the sub-plot. Display day (DD) was treated as the sub-plot treatment. Postmortem age time (PM) and DD were treated as fixed effects. Beef strip loins (N = 18; IMPS #180), obtained from 3 commercial processors (PM = 27, 34, or 37 d), were fabricated into 12 2.54-cm thick steaks (N = 216). Steaks were subdivided into 6 consecutively cut pairs and pairs were randomly assigned to one of 6 display days: 0, 3, 6, 9, 12, and 15. For all pairs, one steak was allocated to microbiological analysis and pH and the paired steak for BIA, objective color assessment, proximate composition, and TBARS. Surface BIA (S-BIA) and internal BIA (I-BIA) assessment were compared. Steaks were packaged on styrofoam trays with a moisture absorbent pad, overwrapped with polyvinyl chloride film, and displayed under fluorescent lighting at 0–4°C in coffin-style retail cases.ResultsThere was a PM × DD interaction (P < 0.05) for S-BIA values. From d 0 to 12 of display, steaks aged 27 d had higher (P < 0.05) S-BIA values than steaks aged 34 and 37 d; however, on d 15 of display, steaks aged 34 d had 22% higher (P < 0.05) S-BIA values than steaks aged 37 d, but had similar (P > 0.05) values compared to steaks aged 27 d. There was no PM × DD interaction (P < 0.05) for I-BIA values; however, an effect on PM and DD was found (P < 0.05). Steaks aged 27 d were 17% higher for I-BIA values (P < 0.05) than 37 d, but similar (P > 0.05) to steaks aged 34 d. For all PM aging times, d 0 had the lowest (P < 0.05) I-BIA values among all display days with 81.44. D 3 was the second lowest (P < 0.05) and 8% higher than d 0 for I-BIA values. D 6 was 16% higher (P < 0.05) than d 3 but similar (P > 0.05) to d 9 and d 12. D 12 and D 15 were similar (P > 0.05). There was a DD × BIA method interaction (P < 0.05). On d 0, 3, and 6, BIA values were different (P < 0.05); however, after d 6 onward, BIA values were similar (P > 0.05). Covariance component was smaller in I-BIA than S-BIA. There were no PM × DD interactions (P > 0.05) for a* and b* values; however, there was an interaction for L* values. Postmortem aging had no effect (P > 0.05) on L*; however, an effect on a* and b* was found (P < 0.05). For APC populations, there was a PM × DD interaction (P < 0.05). No PM × DD interaction or PM effect (P > 0.05) were found for TBARS; however, there was a DD effect (P < 0.05). There was no PM day × DD interaction (P > 0.05) or PM day (P > 0.05) for moisture content. Display day (P < 0.05) had an effect on moisture content. Moderate negative correlations occurred between S-BIA values and a*, b*, and moisture content with –0.48, –0.46, and –0.46, respectively; and –0.51, –0.48, and –0.43, respectively, for I-BIA. Conversely, moderate positive correlation was found between S-BIA values and APC and TBARS with 0.34 and 0.53, respectively; and 0.29 and 0.51, respectively, for I-BIA.ConclusionI-BIA has potential for use to assess shelf-life of retail steaks and it was more precise than S-BIA; however, I-BIA may translocate bacteria into the muscle. Protein degradation and WHC should be evaluated to better understand BIA changes over time.

Sensory and Visual Evaluation of Six Different Beef Shank Cuts from Asian Consumers

ObjectivesThe objective of this study was to evaluate factors affecting Asian consumers’ purchasing decisions and eating preferences of six different beef shank cuts.Materials and MethodsSix shank cuts, three from forequarter [biceps brachii (shank A); a combination of deep digital flexor and flexor digitorum superficialis (shank B); extensor carpi radialis (shank C)], and three from hindquarter [flexor digitorum superficialis (shank D); deep digital flexor (shank E), a combination of long digital extensor, medial digital extensor and peroneus tertius (shank F)] were collected from 12 USDA low choice beef carcasses (n = 72). Shanks from the left side of the carcasses were used for consumer panels and stewed in water for 90 min at 98°C. Asian consumers (n = 91) from Manhattan, KS, evaluated samples for connective tissue texture, amount of connective tissue, juiciness, flavor, overall texture (a combination of myofibrillar tenderness and connective tissue texture) and sensory overall liking. Consumers (n = 84) also visually evaluated the size, surface color and visual overall liking of shank samples from the right side of the carcasses. Finally, consumers rated each sample as either acceptable or unacceptable. All ratings were done on either a Just About Right (JAR) or a continuous line scale.ResultsShanks A, C, D and F received similar scores close to JAR (P > 0.05) for connective tissue texture. Connective tissue texture of shank E was harder than shanks A and D, and shank B was the hardest of all (P < 0.01). For connective tissue amount, shanks A, D, and E received ratings close to JAR (P > 0.05). Consumers rated shank B with too much and shank C and F with too little (P < 0.01) connective tissue. Shanks A, D, and F received similar ratings close to JAR for juiciness (P > 0.05), while shanks C and E were rated less juicy, and shank B was the least juicy among all (P < 0.01). For overall texture, shanks A, D, and F received similar ratings close to JAR (P > 0.05), and shanks C and E were tougher than those rated JAR (P < 0.01). Again, shank B was the toughest among all for overall texture (P < 0.01). Shanks A, D, and F received the highest sensory overall liking scores, followed by shanks C and E, and shank B received the lowest overall liking score among all the shank cuts (P < 0.01). All shank cuts received high sensory acceptability scores (> 85%) except for shank B (62%; P < 0.01). Shanks A and C both received scores that were close to JAR for shank size. Consumers indicated that shanks B, E, and F were too big in size, while shank D was too small (P < 0.01). However, shanks B, C, E, and F had the greatest and similar raw weight (P > 0.05), followed by shank A, while shank D was the lightest of all (P < 0.01). For visual overall liking, shanks A and C received the highest scores, followed by shanks B, E, and F, and shank D received the lowest score (P < 0.05). Shanks A and C were most visually acceptable (> 95%), while shanks B, D, E, and F were less acceptable than shanks A and C (> 70%; P < 0.01). Finally, consumers indicated that there was no difference in flavor and surface color among different shank cuts (P > 0.05).ConclusionConnective tissue texture and amount directly affected Asian consumers’ eating preference for different beef shank cuts, while shank size was the main factor affecting their purchasing decision.

A Proposed Mechanism for Texture Property of Woody Breast in Broilers

ObjectivesWoody breast is a myopathy observed in chicken breast meat (Pectoralis major) characterized by its tough and rubbery texture. However, the exact causation of woody breast texture is still unknown. We hypothesize that sarcoplasmic reticulum (SR) dysfunctionality early postmortem results in rapid leakage of intracellular calcium may partially contribute to the abnormal meat texture observed in woody breast meat. The objective of this preliminary study was to investigate this hypothesis.Materials and MethodsFourteen Ross line broiler breast fillets (7 severe woody breast and 7 normal) were collected at 3 h postmortem from a commercial processing plant located in the southeast United States. The 7 woody breast samples also exhibited moderate to severe white striping. The 7 normal samples did not exhibit any signs of white striping or woody breast. Each sample was trimmed, weighed, vacuum packaged and frozen at –20°C at approximately 8 h postmortem. One 1.9 cm strip across the cranial end of each fillet was fabricated and pulverized in liquid nitrogen to measure sarcomere length (Laser Scan Confocal Microscope with a 100x/NA 1.4 objective), calpain activity (immunoblotting for µ-calpain autolysis), proteolysis (immunoblotting for troponin-T degradation) and collagen content (hydroxyproline content). Purge was also collected from each sample to evaluate protein (bicinchoninic acid assay) and free calcium concentration (atomic absorption).ResultsWoody breast fillets were heavier than normal chicken breast fillets (522.9 vs. 446.9g; P < 0.05). Woody breast samples tended to have shorter sarcomeres (1.70 vs. 2.02 µm; P = 0.0543) and less intact troponin-T compared to normal breast samples (relative intact troponin-T band density: 49.98 vs. 56.97%; P = 0.0515) at 8 h postmortem. It was interesting to note that no µ-calpain band was detected through immunoblotting for both the woody breast and normal samples at 8 h postmortem. Other studies have found similar results as poultry µ-calpain autolyzed at a much rapid rate than µ-calpain in mammalian species. In addition, the purge from woody breast samples also had higher levels of free calcium compared to normal samples (6.2 vs. 4.2 nmol calcium/mg protein; P < 0.05). Lastly, there was more collagen present in the woody breast samples compared to normal chicken breast samples (3.89 vs. 2.08 mg collagen/g muscle tissue; P < 0.05).ConclusionThe results indicated that the cause of texture abnormality of woody breast may be the combined effects of more calcium being released from the SR early postmortem resulting in shorter sarcomere length and more collagen being deposited in the chicken breast meat. Additional research with the focus on SR integrity and functionality as well as collagen crosslinks are needed to further elucidate the basic mechanism of woody breast texture formation.

Assessment of Intrafraction Motion of the Urinary Bladder Using Magnetic Resonance Imaging (cineMRI)

AIM

To assess the intrafraction motion of the urinary bladder and delineate the appropriate margin size for radiotherapy planning, for both the full and empty bladder.

MATERIALS AND METHODS

This was a single-site, single-arm study of 20 patients planned to undergo radical cystectomy for histologically confirmed muscle-invasive bladder cancer. Patients underwent magnetic resonance imaging (cineMRI) of the entire pelvis using a 3-Tesla system, prior to cystectomy. Patients first underwent a cineMRI with a full bladder, then voided and underwent a second MRI with an empty bladder. All MRI sequences were acquired over 18 min. We assessed the differences in bladder filling and subsequent bladder wall displacement, between the empty and full bladder, during a time period consistent with radiotherapy treatment delivery.

RESULTS

Twenty patients underwent cineMRI of the entire pelvis. The maximum mean directional displacements of the bladder walls over the 18 min duration of the scan for the empty bladders were 9.8 mm superiorly, 1.1 mm inferiorly, 2.39 mm anteriorly, 3.73 mm posteriorly, 2.74 mm to the left and 2.48 mm to the right. The maximal mean displacements for the full bladders were 9.2 mm superiorly, 1.1 mm inferiorly, 2.28 mm anteriorly, 1.08 mm posteriorly, 1.85 mm to the left and 1.73 mm to the right. Statistically significant differences were seen in the posterior, left and right displacements but were quantitatively small.

CONCLUSIONS

Intrafractional motion secondary to bladder filling showed minimal variation between the full and empty bladder. Similar clinical target volume to planning target volume margins can be applied for the delivery of radiotherapy for a full and empty bladder.

Abstract P6-02-13: Withdrawn

This abstract was withdrawn by the authors.

Citation Format: Huang C-S, Fann JC-Y, Chen H-H, Hsu G-C, Ho M-F, Chen S-C, Chen Y-J, Chen S-T, Chen C-Y, Sheen-Chen S-M, Chang H-T, Yeh D-C, Chao M, Yeh H-T, Cheng L, Chen D-R, Chang Y-C, Chang K-J. Withdrawn [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P6-02-13.

SP1-induced upregulation of long noncoding RNA LINC00313 contributes to papillary thyroid cancer progression via the miR-422a

OBJECTIVE

Long noncoding RNA LINC00313 (LINC00313) has been reported to be dysregulated in several tumors, including papillary thyroid carcinoma (PTC). Our present study aimed to further explore the potential mechanism of LINC00313 in the progression of papillary thyroid carcinoma (PTC).

PATIENTS AND METHODS

RT-PCR was performed to detect the expression of LINC00313 in both PTC tissues and cell lines. Luciferase reporter and chromatin immunoprecipitation (ChIP) assays were performed to explore whether SP1 could bind to the promoter region of LINC00313 and activate its transcription. The biological functional correlation of LINC00313 was determined by down-regulating the expression of LINC00313 on PTC cell proliferation, apoptosis, migration and invasion. The regulating relationship between LINC00313 and miR-422a was investigated in PTC cells using luciferase reporter assays.

RESULTS

We observed that LINC00313 expression was significantly up-regulated in both PTC tissues and cell lines. Next, the results of bioinformatics analysis and luciferase reporter assays indicated that the transcription factor SP1 can bind to the promoter region of LINC00313 resulting in the overexpression of LINC00313 in PTC. Moreover, functional study revealed that knockdown of LINC00313 significantly suppressed cells proliferation, migration, invasion and EMT. Finally, our results indicated that LINC00313 functioned as an oncogene in PTC in part through serving as a competing endogenous RNA to modulate mi-422a expression.

CONCLUSIONS

Overall, our data demonstrated that SP1-induced LINC00313 contributed to PTC progression by via competitively binding to miR-422a, which may provide a novel therapeutic strategy for PTC.

Does the laparoscopic treatment of paediatric hydroceles represent a better alternative to the traditional open repair technique? A retrospective study of 1332 surgeries performed at two centres in China

Purpose

To evaluate the safety, efficacy and merits of laparoscopic repair in children with hydroceles by comparing the outcomes of laparoscopic repair and the traditional open repair (OR) procedure. The outcomes of the following three laparoscopic percutaneous extra-peritoneal closure (LPEC) approaches were also compared: conventional two-port surgery, transumbilical single-site two-port surgery and single-port surgery.

Methods

We retrospectively compared the demographic, perioperative and follow-up data from the consecutive records obtained for 382 boys who underwent OR and 950 boys who underwent LPEC at two children’s medical centres in China. In the LPEC group, regardless of the hydrocele form, one of the three approaches with percutaneous aspiration was performed: conventional two-port surgery was performed in 387 cases, single-site two-port surgery was performed in 468 cases and single-port surgery was performed in 95 cases. The clinical data and complications were statistically analysed.

Results

Postoperative follow-up data were obtained for all the patients. The mean follow-up time was 36 months (24–48 months) in the OR group and 32.5 months (20–44 months) in the LPEC group. Significant differences in recurrence were not observed between the groups (five in the OR and 10 in the LPEC; P = 0.69). However, the operation time, postoperative hospital stay, incidence of scrotal oedema, incision infection and contralateral metachronous hernia or hydrocele were significantly higher in the OR group than those in the LPEC group (P < 0.01). Eighteen children (4.71%) had a negative exploration of the patent processus vaginalis (PPV) in the OR group. Fourteen children (1.47%) in the LPEC group had a closed internal ring and were converted to a scrotal procedure. Significant differences in the clinical data or complications were not observed between the two centres for the laparoscopic procedure (P > 0.05). Contralateral PPV (cPPV) was found in 18 patients in the single-port group (18.9%). Of the patients affected with cPPV, significant differences were observed between the single-port group and the two-port LPEC group (122 patients, 31.5%, P = 0.016) and the single-site two-port group (the 148 patients, 31.6%, P = 0.013). A contralateral metachronous hernia or hydrocele was found in zero, zero and two cases in these groups, respectively, and significant differences were observed (P < 0.01) between the single-site surgery and the other two laparoscopic approaches.

Conclusions

LPEC is safe, feasible and effective for treating hydroceles in children and has the same recurrence rate as OR. However, LPEC is superior in operation time, hospital stay, occurrence of scrotal oedema, incision infection and occurrence of metachronous hernia or hydrocele. The transumbilical single-site two-port procedure has the same cosmetic effect as the single-port LPEC. According to our experience, the two-port LPEC approach is better for diagnosing cPPV and reducing metachronous hernia or hydrocele than the single-port LPEC procedure.