The Barthel Index predicts surgical textbook outcomes following hepatectomy for elderly patients with hepatocellular carcinoma: A multicenter cohort study.

BACKGROUND: The burgeoning demand for hepatectomy in elderly patients with hepatocellular carcinoma (HCC) necessitates improved perioperative care. Geriatric populations frequently experience functional decline and frailty, predisposing them to adverse postoperative outcomes. The Barthel Index serves as a reliable measure for assessing functional capacity, and this study evaluates its impact on surgical textbook outcomes (TOs) in elderly HCC patients. METHODS: A multicenter retrospective cohort study analyzed elderly patients (≥70 years) following hepatectomy for HCC between 2013 and 2021. Utilizing a Barthel Index cut-off value of 85, patients were divided into two groups: with and without preoperative functional decline and frailty. The primary outcome was the rate of TO, encompassing seven criteria. TO rates were compared between groups, and multivariate logistic regression analyses identified independent risks for achieving TOs. RESULTS: Of 497 elderly patients, 157 (31.6 â€‹%) exhibited preoperative functional decline and frailty (Barthel Index score <85). The overall TO rate was 58.6 â€‹%. Patients with preoperative Barthel Index score <85 had significantly lower TO rates compared to patients with score ≥85 (29.3 â€‹% vs. 72.1 â€‹%, P â€‹< â€‹0.001). Multivariate analysis revealed preoperative Barthel Index score <85 as an independent risk for achieving TO (odds ratio 3.413, 95 â€‹% confidence interval 1.879-6.198, P â€‹< â€‹0.001). Comparable results were observed in the subgroups of patients undergoing open and laparoscopic hepatectomy. CONCLUSION: Preoperative Barthel Index-based assessment of functional decline and frailty significantly predicts TOs following hepatectomy in elderly HCC patients, enabling identification of high-risk patients and informing preoperative management and postoperative care within geriatric oncology.

Development and validation of prealbumin-bilirubin score (preALBI score) for predicting long-term survival after hepatectomy for hepatocellular carcinoma: A multicenter analysis versus ALBI score.

BACKGROUND: The Albumin-Bilirubin (ALBI) score, widely used in predicting long-term prognosis for patients with hepatocellular carcinoma (HCC), has limitations due to serum albumin variability. This study aimed to develop and validate the Prealbumin-Bilirubin (preALBI) score as a reliable alternative. METHODS: A multicenter cohort of HCC patients who underwent hepatectomy was randomly divided into the training and validation cohorts. The preALBI score was developed using Cox regression models within the training cohort, incorporating serum prealbumin and bilirubin levels as crucial determinants. The survival predictive accuracy was evaluated and compared between the preALBI score with two other staging systems, including the ALBI score and the Child-Pugh grade. RESULTS: A total of 2409 patients were enrolled. In the training cohort, the preALBI score demonstrated superior performance in predicting long-term survival after hepatectomy. The preALBI score was associated with the best monotonicity of gradients (linear trend χ2: 72.84) and homogeneity (likelihood ratio χ2: 74.69), and the highest discriminatory ability (the areas under curves for 1-, 3-, and 5-year mortality: 0.663, 0.654, and 0.644, respectively). In addition, the preALBI was the most informative staging system in predicting survival (Akaike information criterion: 11325.65).The results remained consistent in both training and validation cohorts, indicating its reliable performance across different populations. CONCLUSION: The preALBI score, leveraging the stability of prealbumin, represents a promising tool for better patient stratification, providing more accurate prognostic predictions than the ALBI score and the Child-Pugh grade.

Prognostic Value of Serum α-Fetoprotein Level as an Important Characteristic of Tumor Biology for Patients Undergoing Liver Resection of Early-Stage Hepatocellular Carcinoma (BCLC Stage 0/A): A Large Multicenter Analysis.

BACKGROUND AND OBJECTIVE: According to the Barcelona Clinic Liver Cancer (BCLC) algorithm, tumor burden and liver function, but not tumor biology, are the key factors in determining tumor staging and treatment modality, and evaluating treatment prognosis. The serum α-fetoprotein (AFP) level is an important characteristic of hepatocellular carcinoma (HCC) biology, and we aimed to evaluate its prognostic value for patients undergoing liver resection of early-stage HCC. METHODS: Patients who underwent curative liver resection for early-stage HCC were identified from a multi-institutional database. Patients were divided into three groups according to preoperative AFP levels: low (< 400 ng/mL), high (400-999 ng/mL), and extremely-high (≥ 1000 ng/mL) AFP groups. Overall survival (OS) and recurrence rates were compared among these three groups. RESULTS: Among 1284 patients, 720 (56.1%), 262 (20.4%), and 302 (23.5%) patients had preoperative low, high, and extremely-high AFP levels, respectively. The cumulative 5-year OS and recurrence rates were 71.3 and 38.9% among patients in the low AFP group, 66.3 and 48.5% in the high AFP group, and 45.7 and 67.2% in the extremely-high AFP group, respectively (both p < 0.001). Multivariate Cox regression analysis identified both high and extremely-high AFP levels to be independent risk factors of OS (hazard ratio [HR] 1.275 and 1.978, 95% confidence interval [CI] 1.004-1.620 and 1.588-2.464, respectively; p = 0.047 and p < 0.001, respectively) and recurrence (HR 1.290 and 2.050, 95% CI 1.047-1.588 and 1.692-2.484, respectively; p = 0.017 and p < 0.001, respectively). CONCLUSIONS: This study demonstrated the important prognostic value of preoperative AFP levels among patients undergoing resection for early-stage HCC. Incorporating AFP to prognostic estimation of the BCLC algorithm can help guide individualized risk stratification and identify neoadjuvant/adjuvant treatment necessity.

Tumor burden score-AFP-albumin-bilirubin grade score predicts the survival of patients with hepatocellular carcinoma after liver resection.

PURPOSE: There is little information regarding the overall survival (OS) predictive ability of the combination of tumor burden score (TBS), α-fetoprotein (AFP), and albumin-bilirubin (ALBI) grade for patients with hepatocellular carcinoma (HCC). Here, we aimed to develop a model including TBS, AFP, and ALBI grade to predict HCC patient OS following liver resection. METHODS: Patients (N = 1556) from six centers were randomly divided 1:1 into training and validation sets. The X-Tile software was used to determine the optimal cutoff values. The time-dependent area under the receiver operating characteristic curve (AUROC) was calculated to assess the prognostic ability of the different models. RESULTS: In the training set, tumor differentiation, TBS, AFP, ALBI grade, and Barcelona Clinic Liver Cancer (BCLC) stage were independently related to OS. According to the coefficient values of TBS, AFP, and ALBI grade, we developed the TBS-AFP-ALBI (TAA) score using a simplified point system (0, 2 for low/high TBS, 0, 1 for low/high AFP and 0,1 for ALBI grade 1/2). Patients were further divided into low TAA (TAA ≤ 1), medium TAA (TAA = 2-3), and high TAA (TAA= 4) groups. TAA scores (low: referent; medium, HR = 1.994, 95% CI = 1.492-2.666; high, HR = 2.413, 95% CI = 1.630-3.573) were independently associated with patient survival in the validation set. The TAA scores showed higher AUROCs than BCLC stage for the prediction of 1-, 3-, and 5-year OS in both the training and validation sets. CONCLUSION: TAA is a simple score that has better OS prediction performance than the BCLC stage in predicting OS for HCC patients after liver resection.

Association of tumor morphology with long-term prognosis after liver resection for patients with a solitary huge hepatocellular carcinoma-a multicenter propensity score matching analysis.

Background: A solitary hepatocellular carcinoma (HCC) without macrovascular invasion and distant metastasis, regardless of tumor size, is currently classified as early-stage disease by the latest Barcelona Clinic Liver Cancer (BCLC) staging system. While the preferred treatment is surgical resection, the association of tumor morphology with long-term survival outcomes after liver resection for a solitary huge HCC of ≥10 cm has not been defined. Methods: Patients who underwent curative liver resection for a solitary huge HCC were identified from a multicenter database. Preoperative imaging findings were used to define spherical- or ellipsoidal-shaped lesions with smooth edges as balloon-shaped HCCs (BS-HCCs); out-of-shape lesions or lesions of any shape with matt edges were defined as non-balloon-shaped HCCs (NBS-HCCs). The two groups of patients with BS-HCCs and NBS-HCCs were matched in a 1:1 ratio using propensity score matching (PSM). Clinicopathologic characteristics, long-term overall survival (OS) and recurrence-free survival (RFS) were assessed. Results: Among patients with a solitary huge HCC, 74 pairs of patients with BS-HCC and NBS-HCC were matched. Tumor pathological features including proportions of microvascular invasion, satellite nodules, and incomplete tumor encapsulation in the BS-HCC group were lower than the NBS-HCC group. At a median follow-up of 50.7 months, median OS and RFS of all patients with a solitary huge HCC after PSM were 27.8 and 10.1 months, respectively. The BS-HCC group had better median OS and RFS than the NBS-HCC group (31.9 vs. 21.0 months, P=0.01; and 19.7 vs. 6.4 months, P=0.015). Multivariate analyses identified BS-HCC as independently associated with better OS (HR =0.592, P=0.009) and RFS (HR =0.633, P=0.013). Conclusions: For a solitary huge HCC, preoperative imaging on tumor morphology was associated with prognosis following resection. In particular, patients with BS-HCCs had better long-term survival following liver resection versus patients with large NBS-HCCs.

Predictors and long-term prognosis of early and late recurrence for patients undergoing hepatic resection of hepatocellular carcinoma: a large-scale multicenter study.

Background: Recurrence is common among patients undergoing hepatic resection for hepatocellular carcinoma (HCC), which greatly limits long-term survival. We aimed to identify predictors and long-term prognosis of early and late recurrence after HCC resection. Methods: Multicenter data of patients who underwent HCC resection between 2002 and 2016 were analyzed. Recurrence was divided into early (≤2 years) and late recurrence (>2 years after surgery). Predictors of early and late recurrence, and prognostic factors of post-recurrence survival (PRS) were identified by univariate and multivariate analyses. Results: Among 1,426 patients, 554 (38.8%) and 348 (24.4%) developed early and late recurrence, respectively. Independent predictors associated with early recurrence included preoperative alpha-fetoprotein level >400 µg/L, resection margin <1 cm, and tumor size >5.0 cm, multiplicity, macrovascular and microvascular invasion, and satellites of the initial tumor at the first diagnosis of HCC; independent predictors associated with late recurrence included male, cirrhosis, and tumor size >5.0 cm, multiplicity, macrovascular and microvascular invasion, and satellites of the initial tumor. Patients with early recurrence had a lower likelihood of undergoing potentially curative treatments for recurrence (37.2% vs. 48.0%, P<0.001) and a worse median PRS (13.5 vs. 36.6 months, P<0.001) vs. patients who had late recurrence. Multivariate analysis revealed that early recurrence and irregular postoperative surveillance were independently associated with worse PRS [hazard ratio (HR) =1.250, 95% CI: 1.016-1.538, P=0.035; and HR =1.983, 95% CI: 1.677-2.345, P<0.001]. Conclusions: Predictors associated with early and late recurrence after curative resection for patients with HCC were generally same, although several did differ. Patients with late recurrence had better long-term survival than patients with early recurrence.

Assessment of cellular responses in three-dimensional cell cultures through chemical exchange saturation transfer and 1 H MRS.

The article from this special issue was previously published in NMR In Biomedicine , Volume 35, Issue 9, 2022. For completeness we are including the title page of the article below. The full text of the article can be read in Issue 35:9 on Wiley Online Library: https://doi.org/10.1002/nbm.4757.

Postoperative infectious complications following laparoscopic versus open hepatectomy for hepatocellular carcinoma: a multicenter propensity score analysis of 3876 patients.

OBJECTIVES: Hepatocellular carcinoma (HCC) is a common indication for hepatectomy that is often complicated by postoperative complication. The authors sought to investigate the relationship between the open with laparoscopic approach of hepatectomy and incidences of postoperative infectious complications. PATIENTS AND METHODS: Using a multicenter database, HCC patients who underwent laparoscopic hepatectomy (LH) or open hepatectomy (OH) were reviewed and analyzed. Propensity score matching (PSM), inverse probability of treatment weight (IPTW), and multivariate logistic regression analyses were utilized to assess the association of the operative approach with postoperative infectious complications, including incisional surgical site infection (SSI), organ/space SSI, and remote infection (RI). RESULTS: Among 3876 patients, 845 (21.8%) and 3031 (78.2%) patients underwent LH and OH, respectively. The overall incidence of infection was 6.9 versus 14.6% among patients who underwent LH versus OH, respectively ( P <0.001). Of note, the incidences of incisional SSI (1.8 vs. 6.3%, P <0.001), organ/space SSI (1.8 vs. 4.6%, P <0.001), and RI (3.8 vs. 9.8%, P <0.001) were all significantly lower among patients who underwent LH versus OH. After PSM (6.9, 1.8, 1.8, and 3.8% vs. 18.5, 8.4, 5.2, and 12.8%, respectively) and IPTW (9.5, 2.3, 2.1, and 5.5% vs. 14.3, 6.3, 4.5, and 9.8%, respectively), LH remained associated with statistically lower incidences of all types of infectious complications. After adjustment for other confounding factors on multivariate analyses, LH remained independently associated with lower incidences of overall infection, incisional SSI, organ/space SSI, and RI in the overall, PSM, and IPTW cohorts, respectively. CONCLUSION: Compared with open approach, laparoscopic approach was independently associated with lower incidences of postoperative infectious complications following hepatectomy for HCC.

Prospective validation of the Eastern Staging in predicting survival after surgical resection for patients with hepatocellular carcinoma: a multicenter study from China.

BACKGROUND: The Eastern Staging System, which was specially developed for patients undergoing surgical resection for hepatocellular carcinoma (HCC), has been proposed for more than ten years. To prospectively validate the predictive accuracy of the Eastern staging on long-term survival after HCC resection. METHODS: Patients who underwent hepatectomy for HCC from 2011 to 2020 at 10 Chinese hospitals were identified from a prospectively collected database. The survival predictive accuracy was evaluated and compared between the Eastern Staging with six other staging systems, including the JIS, BCLC, Okuda, CLIP, 8th AJCC TNM, and HKLC staging. RESULTS: Among 2365 patients, the 1-, 3-, and 5-year overall survival rates were 84.2%, 64.5%, and 52.6%, respectively. Among these seven staging systems, the Eastern staging was associated with the best monotonicity of gradients (linear trend χ2: 408.5) and homogeneity (likelihood ratio χ2: 447.3), and the highest discriminatory ability (the areas under curves for 1-, 3-, and 5-year mortality: 0.776, 0.787, and 0.768, respectively). In addition, the Eastern staging was the most informative staging system in predicting survival (Akaike information criterion: 2982.33). CONCLUSION: Using a large multicenter prospectively collected database, the Eastern Staging was found to show the best predictive accuracy on long-term overall survival in patients with resectable HCC than the other 6 commonly-used staging systems.

Comparing Genetic Risk and Clinical Risk Classification in Luminal-like Breast Cancer Patients Using a 23-Gene Classifier.

Background: A 23-gene classifier has been developed based on gene expression profiles of Taiwanese luminal-like breast cancer. We aim to stratify risk of relapse and identify patients who may benefit from adjuvant chemotherapy based on genetic model among distinct clinical risk groups. Methods: There were 248 luminal (hormone receptor-positive and human epidermal growth factor receptor II-negative) breast cancer patients with 23-gene classifier results. Using the modified Adjuvant! Online definition, clinical high/low-risk groups were tabulated with the genetic model. The primary endpoint was a recurrence-free interval (RFI) at 5 years. Results: There was a significant difference between the high/low-risk groups defined by the 23-gene classifier for the 5-year prognosis of recurrence (16 recurrences in high-risk and 3 recurrences in low-risk; log-rank test: p < 0.0001). Among the clinically high-risk group, the 5-year RFI of high risk defined by the 23-gene classifier was significantly higher than that of the low-risk group (15 recurrences in high-risk and 2 recurrences in low-risk; log-rank test: p < 0.0001). Conclusion: This study showed that 23-gene classifier can be used to stratify clinically high-risk patients into distinct survival patterns based on genomic risks and displays the potentiality to guide adjuvant chemotherapy. The 23-gene classifier can provide a better estimation of breast cancer prognosis which can help physicians make a better treatment decision.

Prognostic Comparison between Oncotype DX® and a 23-Gene Classifier, RecurIndex®, on the Taiwan Breast Cancer Population.

The applicability of the Oncotype DX® (Genomic Health, Inc., Redwood City, CA, USA) recurrence score (RS) in Asian populations is unclear. A 23-gene classifier, RecurIndex® (Amwise Diagnostics, Pte. Ltd., Singapore), has been developed based on the gene expression profiles of early-stage breast cancer patients of ethnic Han Chinese population in Taiwan. This study aimed to compare the performance of the Oncotype DX® RS with the RecurIndex® recurrence index (RI) for predicting relapse-free survival. Therefore, we calculated both the RI and RS for 110 early stage breast cancer patients, with the cut-off value for high-risk recurrence set at 26 and 29 for the RS and the RI, respectively. With relapse-free interval (RFI) as the primary endpoint, the concordance between RS and RI was 78.2% (Kappa value = 0.297). For a median follow-up interval of 27 months, there was a statistically significant difference in RFI between the high- and low-risk groups defined by the RI (p = 0.04) but not between risk groups defined by the RS (p = 0.66). In conclusion, whereas there was high concordance between the RecurIndex® RI and the Oncotype DX RS, the current data showed that the RI had a better discrimination for recurrence risk than the RS. Subsequent studies with larger sample sizes will be needed to confirm the superiority of the RI over the RS in the Asian population.

Development and validation of safety and efficacy-associated risk calculator for hepatocellular carcinoma in the elderly after resection (SEARCHER): A multi-institutional observational study.

BACKGROUND: Increased life expectancy and improved perioperative management have resulted in increased utilization of hepatectomy for hepatocellular carcinoma (HCC) among elderly patients. However, individualized model for predicting the surgical safety and efficacy is lacking. The present study aimed to develop a safety and efficacy-associated risk calculator for HCC in the elderly after resection (SEARCHER). METHODS: From an international multicenter database, elderly patients who underwent curative-intent hepatectomy for HCC were stratified by patient age: 65-69 years, 70-74 years, 75-79 years, and ≥80 years. Short- and long-term outcomes among the 4 groups were compared. Univariate and multivariate analyses of risk factors of postoperative major morbidity, cancer-specific survival (CSS) and overall survival (OS) were performed in the training cohort. A nomogram-based online calculator was then constructed and validated in the validation cohort. RESULTS: With increasing age, the risk of postoperative major morbidity and worse OS increased (P = 0.001 and 0.020), but not postoperative mortality and CSS (P = 0.577 and 0.890) among patients across the 4 groups. Based on three nomograms to predict major morbidity, CSS and OS, the SEARCHER model was constructed and made available at https://elderlyhcc.shinyapps.io/SEARCHER. The model demonstrated excellent calibration and optimal performance in both the training and validation cohorts, and performed better than the several commonly-used conventional scoring and staging systems of HCC. CONCLUSIONS: With higher potential postoperative major morbidity and worse OS as patients age, the decision of whether to perform a hepatectomy for HCC needs to be comprehensively considered in the elderly. The proposed SEARCHER model demonstrated good performance to individually predict safety and efficacy of hepatectomy in elderly patients with HCC.

A Web-Based Prediction Model for Estimating the Probability of Post-hepatectomy Major Complications in Patients with Hepatocellular Carcinoma: A Multicenter Study from a Hepatitis B Virus-Endemic Area.

BACKGROUND: The identification of patients at high risk of developing postoperative complications is important to improve surgical safety. We sought to develop an individualized tool to predict post-hepatectomy major complications in hepatitis B virus (HBV)-infected patients with hepatocellular carcinoma (HCC). METHODS: A multicenter database of patients undergoing hepatectomy for HCC were analyzed; 2/3 and 1/3 of patients were assigned to the training and validation cohorts, respectively. Independent risks of postoperative 30-day major complications (Clavien-Dindo grades III-V) were identified and used to construct a web-based prediction model, which predictive accuracy was assessed using C-index and calibration curves, which was further validated by the validation cohort and compared with conventional scores. RESULTS: Among 2762 patients, 391 (14.2%) developed major complications after hepatectomy. Diabetes mellitus, concurrent hepatitis C virus infection, HCC beyond the Milan criteria, cirrhosis, preoperative HBV-DNA level, albumin-bilirubin (ALBI), and aspartate transaminase to platelet ratio index (APRI) were identified as independent predictors of developing major complications, which were used to construct the online calculator ( http://www.asapcalculate.top/Cal11_en.html ). This model demonstrated good calibration and discrimination, with the C-indexes of 0.752 and 0.743 in the training and validation cohorts, respectively, which were significantly higher than those conventional scores (the training and validation cohorts: 0.565 ~ 0.650 and 0.568 ~ 0.614, all P < 0.001). CONCLUSIONS: A web-based prediction model was developed to predict the probability of post-hepatectomy major complications in an individual HBV-infected patient with HCC. It can be used easily in the real-world clinical setting to help management-related decision-making and early warning, especially in areas with endemic HBV infection.

Risk factors and long-term prognosis of beyond-Milan recurrence after hepatectomy for BCLC stage 0/A hepatocellular carcinoma: A large-scale multicenter study.

BACKGROUND: Data on recurrence are important to inform surveillance and improve long-term surgical outcomes for patients with hepatocellular carcinoma. We sought to identify risk factors and long-term prognosis among patients who experienced beyond-Milan recurrence after hepatectomy for early-stage hepatocellular carcinoma. METHODS: Patients who underwent hepatectomy for Barcelona Clinic Liver Cancer stage 0/A hepatocellular carcinoma were identified from a multi-institutional database. Predictors of beyond-Milan recurrence and risk factors associated with post-recurrence survival among patients with beyond-Milan recurrence were assessed using univariate and multivariate Cox regression analyses. RESULTS: Among 753 patients (median follow-up, 51.8 months), 138 (18.3%) developed beyond-Milan recurrence. Regular surveillance (interval follow-up ≤3 months within 1 year and ≤6 months in subsequent years after surgery) was not carried out for 53 (38.4%) patients who developed beyond-Milan recurrence. On multivariate analysis, increased risk of beyond-Milan recurrence was independently associated with preoperative alpha-fetoprotein level >400 ng/mL, tumor size >5.0 cm, multifocal disease, microvascular invasion, and no/irregular recurrence surveillance. Median post-recurrence survival among patients with beyond-Milan recurrence was only 8.4 months (95% confidence interval: 7.0-9.8 months). Among patients who developed beyond-Milan recurrence, Child-Pugh grade B/C, early recurrence within 1 year after surgery, macrovascular invasion/distant metastasis, and noncurative treatment of recurrence were independent risk factors associated with worse post-recurrence survival. CONCLUSION: Nearly 1 in 5 patients developed beyond-Milan recurrence after hepatectomy for early-stage hepatocellular carcinoma. Patients with beyond-Milan recurrence had a median survival of less than 1 year after diagnosis of the recurrence. Regular surveillance is an important and actionable measure to decrease beyond-Milan recurrence and, in turn, improve long-term survival among patients treated with hepatectomy for hepatocellular carcinoma.

Chemical Exchange Saturation Transfer (CEST) Signal at -1.6 ppm and Its Application for Imaging a C6 Glioma Model.

The chemical exchange saturation transfer (CEST) signal at -1.6 ppm is attributed to the choline methyl on phosphatidylcholines and results from the relayed nuclear Overhauser effect (rNOE), that is, rNOE(-1.6). The formation of rNOE(-1.6) involving the cholesterol hydroxyl is shown in liposome models. We aimed to confirm the correlation between cholesterol content and rNOE(-1.6) in cell cultures, tissues, and animals. C57BL/6 mice (N = 9) bearing the C6 glioma tumor were imaged in a 7 T MRI scanner, and their rNOE(-1.6) images were cross-validated through cholesterol staining with filipin. Cholesterol quantification was obtained using an 18.8-T NMR spectrometer from the lipid extracts of the brain tissues from another group of mice (N = 3). The cholesterol content in the cultured cells was manipulated using methyl-ß-cyclodextrin and a complex of cholesterol and methyl-ß-cyclodextrin. The rNOE(-1.6) of the cell homogenates and their cholesterol levels were measured using a 9.4-T NMR spectrometer. The rNOE(-1.6) signal is hypointense in the C6 tumors of mice, which matches the filipin staining results, suggesting that their tumor region is cholesterol deficient. The tissue extracts also indicate less cholesterol and phosphatidylcholine contents in tumors than in normal brain tissues. The amplitude of rNOE(-1.6) is positively correlated with the cholesterol concentration in the cholesterol-manipulated cell cultures. Our results indicate that the cholesterol dependence of rNOE(-1.6) occurs in cell cultures and solid tumors of C6 glioma. Furthermore, when the concentration of phosphatidylcholine is carefully considered, rNOE(-1.6) can be developed as a cholesterol-weighted imaging technique.

Assessment of cellular responses in three-dimensional cell cultures through chemical exchange saturation transfer and 1 H MRS.

Metabolic responses to physiological changes have been detected using chemical exchange saturation transfer (CEST) imaging in clinical settings. Similarly to other MRI techniques, the CEST technique was based originally on phantoms from buffer solutions and was then further developed through animal experiments. However, CEST imaging can capture certain dynamics of metabolism that solution phantoms cannot model. Cell culture phantoms can fill the gap between buffer phantoms and animal models. In this study, we used 1 H NMR and CEST in a B0 field of 9.4 T to investigate HEK293T cells from two-dimensional (2D) cultures, three-dimensional (3D) cultures, and 3D cultures seeded with cell spheroids. Two CEST dips were observed: the magnitude of the amine dip at 2.8 ppm increased during the incubation period, whereas the hydroxyl dip at 1.2 ppm remained approximately the same or modestly increased. We also observed a CEST dip at 2.8 ppm from the 2D culture responding dramatically to doxorubicin treatment. By cross-validating with pH values and the concentrations of amine and hydroxyl protons extracted through 1 H NMR, we observed that they did not correspond to an increase in the amine pool. We believe that the denaturation or degradation of proteins from the fetal bovine serum increased the size of the amine pool. Although 3D culture conditions can be further improved, our study suggests that 3D cultures have the potential to bridge studies of solution phantoms and those on animals.