Correlation of GLUT-1 overexpression, tumor size, and depth of invasion with 18F-2-fluoro-2-deoxy-D-glucose uptake by positron emission tomography in colorectal cancer

Value of glucose transport protein 1 expression in detecting lymph node metastasis in patients with colorectal cancer

BACKGROUND

There are limited data on the use of glucose transport protein 1 (GLUT-1) expression as a biomarker for predicting lymph node metastasis in patients with colorectal cancer. GLUT-1 and GLUT-3, hexokinase (HK)-II, and hypoxia-induced factor (HIF)-1 expressions may be useful biomarkers for detecting primary tumors and lymph node metastasis when combined with fluorodeoxyglucose (FDG) uptake on positron emission tomography/computed tomography (PET/CT).

AIM

To evaluate GLUT-1, GLUT-3, HK-II, and HIF-1 expressions as biomarkers for detecting primary tumors and lymph node metastasis with 18F-FDG-PET/CT.

METHODS

This retrospective study included 169 patients with colorectal cancer who underwent colectomy and preoperative 18F-FDG-PET/CT at Chungbuk National University Hospital between January 2009 and May 2012. Two tissue cores from the central and peripheral areas of the tumors were obtained and were examined by a dedicated pathologist, and the expressions of GLUT-1, GLUT-3, HK-II, and HIF-1 were determined using immunohistochemical staining. We analyzed the correlations among their expressions, various clinicopathological factors, and the maximum standardized uptake value (SUVmax) of PET/CT.

RESULTS

GLUT-1 was found at the center or periphery of the tumors in 109 (64.5%) of the 169 patients. GLUT-1 positivity was significantly correlated with the SUVmax of the primary tumor and lymph nodes, regardless of the biopsy site (tumor center, P < 0.001 and P = 0.012; tumor periphery, P = 0.030 and P = 0.010, respectively). GLUT-1 positivity and negativity were associated with higher and lower sensitivities of PET/CT, respectively, for the detection of lymph node metastasis, regardless of the biopsy site. GLUT3, HK-II, and HIF-1 expressions were not significantly correlated with the SUVmax of the primary tumor and lymph nodes.

CONCLUSION

GLUT-1 expression was significantly correlated with the SUVmax of 18F-FDG-PET/CT for primary tumors and lymph nodes. Clinicians should consider GLUT-1 expression in preoperative endoscopic biopsy in interpreting PET/CT findings.

Patlak Reconstruction Using Dynamic 18 F-FDG PET Imaging for Evaluation of Malignant Liver Tumors : A Comparison of HCC, ICC, and Metastatic Liver Tumors

PURPOSE OF THE REPORT

The aim of this study was to explore the different patterns of dynamic whole-body (D-WB) FDG PET/CT parameters among liver malignancy types as potential diagnostic clues and investigate the association between static and dynamic PET/CT parameters for each tumor histology.

PATIENTS AND METHODS

Seventy-one patients with intrahepatic cholangiocarcinoma (ICC), metastatic liver tumor (MLT), or hepatocellular carcinoma (HCC) who underwent D-WB and static dual-time-point FDG PET/CT were enrolled. We obtained Pearson correlation coefficients between the metabolic rate of FDG (MR FDG ; mg/min/ 100ml) or distribution volume of free FDG (DV FDG , %) and static PET/CT parameters. We compared MR FDG and DV FDG values by tumor type and performed receiver operating characteristic analyses for MR FDG and static images.

RESULTS

A total of 12 ICC, 116 MLT, and 36 HCC lesions were analyzed. MR FDG and DV FDG showed excellent correlation with early (SUV e ) and delayed SUV max (SUV d ) ( r = 0.71~0.97), but DV FDG in the HCC lesions did not ( r = 0.62 and 0.69 for SUV e and SUV d , respectively) ( P < 0.001 for all). HCC lesions showed significantly lower MR FDG (2.43 ± 1.98) and DV FDG (139.95 ± 62.58) than ICC (5.02 ± 3.56, 207.06 ± 97.13) and MLT lesions (4.51 ± 2.47, 180.13 ± 75.58) ( P < 0.01 for all). The optimal MR FDG could differentiate HCC from ICC and MLT with areas under the curve of 0.84 and 0.80, respectively. Metastatic liver tumor lesions showed the widest distribution of MR FDG and DV FDG values but with no significant difference among most primary sites.

CONCLUSIONS

MR FDG was strongly correlated with SUV max in the 3 malignancies and showed utility for differentiating HCC from ICC and MLT. Each tumor type has a different glucose metabolism, and D-WB FDG PET/CT imaging has the potential to visualize those differences.

Epigenetic and metabolic reprogramming in inflammatory bowel diseases: diagnostic and prognostic biomarkers in colorectal cancer

BACKGROUND AND AIM

"Inflammatory bowel disease" (IBD) is a chronic, relapsing inflammatory disease of the intestinal tract that typically begins at a young age and might transit to colorectal cancer (CRC). In this manuscript, we discussed the epigenetic and metabolic change to present a extensive view of IBDs transition to CRC. This study discusses the possible biomarkers for evaluating the condition of IBDs patients, especially before the transition to CRC.

RESEARCH APPROACH

We searched "PubMed" and "Google Scholar" using the keywords from 2000 to 2022.

DISCUSSION

In this manuscript, interesting titles associated with IBD and CRC are discussed to present a broad view regarding the epigenetic and metabolic reprogramming and the biomarkers.

CONCLUSION

Epigenetics can be the main reason in IBD transition to CRC, and Hypermethylation of several genes, such as VIM, OSM4, SEPT9, GATA4 and GATA5, NDRG4, BMP3, ITGA4 and plus hypomethylation of LINE1 can be used in IBD and CRC management. Epigenetic, metabolisms and microbiome-derived biomarkers, such as Linoleic acid and 12 hydroxy 8,10-octadecadienoic acid, Serum M2-pyruvate kinase and Six metabolic genes (NAT2, XDH, GPX3, AKR1C4, SPHK and ADCY5) expression are valuable biomarkers for early detection and transition to CRC condition. Some miRs, such as miR-31, miR-139-5p, miR -155, miR-17, miR-223, miR-370-3p, miR-31, miR -106a, miR -135b and miR-320 can be used as biomarkers to estimate IBD transition to CRC condition.

SLC2As as diagnostic markers and therapeutic targets in LUAD patients through bioinformatic analysis

Facilitative glucose transporters (GLUTs), which are encoded by solute carrier 2A (SLC2A) genes, are responsible for mediating glucose absorption. In order to meet their higher energy demands, cancer cells are more likely than normal tissue cells to have elevated glucose transporters. Multiple pathogenic processes, such as cancer and immunological disorders, have been linked to GLUTs. Few studies, meanwhile, have been conducted on individuals with lung adenocarcinoma (LUAD) to evaluate all 14 SLC2A genes. We first identified increased protein levels of SLC2A1, SLC2A5, SLC2A6, and SLC2A9 via HPA database and downregulated mRNA levels of SLC2A3, SLC2A6, SLC2A9, and SLC2A14 by ONCOMINE and UALCAN databases in patients with LUAD. Additionally, lower levels of SLC2A3, SLC2A6, SLC2A9, SLC2A12, and SLC2A14 and higher levels of SLC2A1, SLC2A5, SLC2A10, and SLC2A11 had an association with advanced tumor stage. SLC2A1, SLC2A7, and SLC2A11 were identified as prognostic signatures for LUAD. Kaplan-Meier analysis, Univariate Cox regression, multivariate Cox regression and ROC analyses further revealed that these three genes signature was a novel and important prognostic factor. Mechanistically, the aberrant expression of these molecules was caused, in part, by the hypomethylation of SLC2A3, SLC2A10, and SLC2A14 and by the hypermethylation of SLC2A1, SLC2A2, SLC2A5, SLC2A6, SLC2A7, and SLC2A11. Additionally, SLC2A3, SLC2A5, SLC2A6, SLC2A9, and SLC2A14 contributed to LUAD by positively modulating M2 macrophage and T cell exhaustion. Finally, pathways involving SLC2A1/BUB1B/mitotic cell cycle, SLC2A5/CD86/negative regulation of immune system process, SLC2A6/PLEK/lymphocyte activation, SLC2A9/CD4/regulation of cytokine production might participate in the pathogenesis of LUAD. In summary, our results will provide the theoretical basis on SLC2As as diagnostic markers and therapeutic targets in LUAD.

Angiopoietin-like 4 promotes glucose metabolism by regulating glucose transporter expression in colorectal cancer

PURPOSE

Angiopoietin-like 4 (ANGPTL4) was recently shown to be associated with cancer progression but little is known about its contribution to cancer metabolism. The purpose of this study was to elucidate the role of ANGPTL4 in glucose metabolism in colorectal cancer (CRC).

METHODS

Immunohistochemical staining of CRC specimens classified 84 patients into two groups according to ANGPTL4 expression. Clinicopathological characteristics, gene mutation status obtained by next-generation sequencing, and fluorodeoxyglucose (FDG) uptake measured by positron emission tomography/computed tomography (PET/CT) were compared between the two groups. Furthermore, the impact of ANGPTL4 expression on cancer metabolism was investigated by a subcutaneous xenograft mouse model using the ANGPTL4 knockout CRC cell line, and glucose transporter (GLUT) expression was evaluated.

RESULTS

There were significantly more cases of T3/4 tumours (94.3% vs. 57.1%, P < 0.001) and perineural invasion (42.9% vs. 22.4%, P = 0.046) in the ANGPTL4-high group than in the low group. Genetic exploration revealed a higher frequency of KRAS mutation (54.3% vs. 22.4%, P = 0.003) in the ANGPTL4-high tumours. All the FDG uptake parameters were significantly higher in ANGPTL4-high tumours. In vivo analysis showed a significant reduction in tumour size due to ANGPTL4 knockout with lower expression of GLUT1 and GLUT3, and suppression of AKT phosphorylation.

CONCLUSION

ANGPTL4 regulates the expression of GLUTs by activating the PI3K-AKT pathway and thereby promoting glucose metabolism in CRC. These findings establish a new functional role of ANGPTL4 in cancer progression and lay the foundation for developing a novel therapeutic target.

LncRNA GAL promotes colorectal cancer liver metastasis through stabilizing GLUT1

Colorectal cancer liver metastasis (CRLM) is the leading cause of colorectal cancer-related deaths and remains a clinical challenge. Enhancement of glucose uptake is involved in CRLM; however, whether long noncoding RNAs (lncRNAs) participate in these molecular events remains largely unclear. Here, we report an lncRNA, GAL (glucose transporter 1 (GLUT1) associated lncRNA), that was upregulated in CRLM tissues compared with primary colorectal cancer (CRC) tissues or matched normal tissues and was associated with the overall survival rates of CRLM patients. Functionally, GAL served as an oncogene because it promoted CRC cell migration and invasion in vitro and enhanced the ability of CRC cells to metastasize from the intestine to the liver in vivo. Mechanistically, GAL interacted with the GLUT1 protein to increase GLUT1 SUMOylation, inhibiting the effect of the ubiquitin-proteasome system on the GLUT1 protein. GLUT1-knockout (-/+) repressed the GAL-mediated increase in CRC cell uptake of glucose, migrate, and invade in vitro, as well as metastasis from the intestine to the liver in vivo, and enforced expression of GLUT1 rescued GAL knockout-induced biological functions in CRC cells. Taken together, our findings demonstrated that GAL promotes CRLM by stabilizing GLUT1, suggesting that the GAL-GLUT1 complex may act as a potential therapeutic target for CRLM.

F-18 FDG PET/CT Imaging in Normal Variants, Pitfalls and Artifacts in the Abdomen and Pelvis

Since its introduction into clinical practice, multimodality imaging has revolutionized diagnostic imaging for both oncologic and non-oncologic pathologies. 18F-fluorodeoxyglucose (18F-FDG) PET/CT imaging which takes advantage of increased anaerobic glycolysis that occurs in tumor cells (Warburg effect) has gained significant clinical relevance in the management of most, if not all oncologic conditions. Because FDG is taken by both normal and abnormal tissues, PET/CT imaging may demonstrate several normal variants and imaging pitfalls. These may ultimately impact disease detection and diagnostic accuracy. Imaging specialists (nuclear medicine physicians and radiologists) must demonstrate a thorough understanding of normal and physiologic variants in the distribution of 18F-FDG; including potential imaging pitfalls and technical artifacts to minimize misinterpretation of images. The normal physiologic course of 18F-FDG results in a variable degree of uptake in the stomach, liver, spleen, small and large bowel. Urinary excretion results in renal, ureteric, and urinary bladder uptake. Technical artifacts can occur due to motion, truncation as well as the effects of contrast agents and metallic hardware. Using pictorial illustrations, this paper aims to describe the variants of physiologic 18F-FDG uptake that may mimic pathology as well as potential benign conditions that may result in misinterpretation of PET/CT images in common oncologic conditions of the abdomen and pelvis.

Correlation of primary tumor metabolic parameters with clinical, histopathological and molecular characteristics in breast cancer patients at pre-operative staging FDG-PET/CT study

Background

The aim of this prospective study was to evaluate the correlation of primary tumor metabolic activity parameters; maximum standardized uptake value (SUVmax) and tumor SUVmax/liver average SUV ratio (TLR) with clinical, histopathological and molecular characteristics of initial staging breast cancer (BC) patients using 18F-fluorodeoxyglucose (FDG) positron emission tomography / computerized tomography (PET/CT) scan.

Results

Forty female patients with newly diagnosed BC were enrolled in our study, age ranging from 31-78 years (mean 50.5 +/- SD11.7).

All the primary tumors were detected with mean SUVmax 10.8(+/-SD 7.9). The mean /median SUVmax values of primary tumor was higher in premenopausal , stage III and IV, Estrogen Receptors negative( ER-), Progesterone Receptors negative(PR-), Human epidermal growth factor receptor 2 positive ( Her2neu+) patients, high nuclear grade (GIII), triple negative molecular subgroup (TN) and positive axillary lymph node (ALNs) metastasis,(P= 0.003, 0.017, 0.113, 0.089 0.01 ,0.002 , 0.007 and 0.016 respectively).

The mean/median TLR values was higher in premenopausal ,Her2neu+, GIII, TN molecular subtype patients, stage III and IV and in patients with positive ALNs , ER- and PR - patients (P= 0.002, 0.0476 , 0.005 , 0.018 , 0.039 and 0.022, 0.095 and 0.129 respectively).

SUVmax of the primary lesion and TLR were moderately negatively correlated with the age of the patients (P= 0.005 and 0.008 respectively), also they were moderately positively correlated with the size of the primary tumor (P= 0.019 and 0.036 respectively). TLR was predictive of nodal involvement AUC= 0.612 (95% CI: 0.431-792). The overall sensitivity and specificity of PET/CT for axillary staging was 100 % and 60 %, respectively (P= 0.006).

Conclusion

The SUVmax of the primary tumor and TLR values had similar significant associations with different prognostic factors in BC but only TLR can predict nodal involvement.

18F-FDG PET/CT metabolic parameters correlate with EIF2S2 expression status in colorectal cancer

Background: We sought to investigate whether the expression of the gene EIF2S2 is related to ¹⁸F-FDG PET/CT metabolic parameters in patients with colorectal cancer (CRC).

Materials and methods: The expression of EIF2S2 in CRC and its relationship with clinicopathological features were obtained through the ONCOMINE, UALCAN and GEPIA databases. EIF2S2 and GLUT1 expression were examined by immunohistochemistry in 42 CRC patients undergoing preoperative PET-CT examination. Spearman correlation analysis was used to assess the relationship between EIF2S2 and GLUT1 levels and clinical parameters. Correlation analysis between EIF2S2 and Reactome-Glycolysis signatures was performed using GEPIA2. We describe the effect of EIF2S2 knockdown on lactate production and the mRNA levels of glycolysis-related genes in human colon cancer SW480 cells.

Results: Immunohistochemistry revealed an upregulation of EIF2S2 protein expression in tumor tissues of colorectal cancer patients, which is consistent with the significant upregulation of EIF2S2 transcript levels in the database. These colorectal cancer patients included 24 cases of colon cancer and 18 cases of rectal cancer, ranging in age from 31 to 78 years. The transcription was significantly related to histological subtypes and TP53 mutations (P <0.05). The value of SUVmax in CRC significantly correlated with the expression of EIF2S2 (rho = 0.462, P <0.01). Although SUVmax and SUVmean was not correlate with the expression of GLUT1 (P <0.05), a significant correlation was observed between the expression of GLUT1 and the volumetric PET parameters, such as MTV and TLG (P < 0.01). GLUT1 expression in CRC was positively correlated with EIF2S2 status (rho = 0.470, P <0.01). In SW480 cells, RNAi-mediated depletion of EIF2S2 inhibited lactic acid production (P <0.05) and SLC2A1, SLC2A3, SLC2A10, HK2, PKM2, LDHA mRNA level (P <0.01).

Conclusions: Primary CRC FDG uptake is strongly associated with the overexpression of EIF2S2, and EIF2S2 may promote glycolysis in CRC by mediating GLUT1.

Determining the immunohistochemical expression of GLUT1 in renal cell carcinoma using the HSCORE method

The aim of the present study was to compare the immunohistochemical expression of glucose transporter 1 (GLUT1) between the most common histological types of renal cell carcinoma (RCC), and to determine whether a correlation between GLUT1 expression and nuclear grade or tumor size exists. A total of 19 RCC samples were selected for the study, consisting of 8 clear cell (cc)RCC and 11 non-ccRCC tissues. Immunohistochemistry for GLUT1 was performed on formalin-fixed and paraffin-embedded sections using GLUT1 antibodies. All data analyses were performed using the MedCalc software. There was a higher immunohistochemical expression of GLUT1 in the ccRCC group compared with the non-cc group, but there was no difference in GLUT1 expression between groups of RCCs with differing nuclear grades. No significant correlation between GLUT1 expression and tumor size was found. The higher immunohistochemical expression of GLUT1 in ccRCC may be a contributing factor to the clinical characteristics and behavior of that group of carcinomas. These results suggest that GLUT1 expression cannot be used as a prognostic factor for RCC, but it may be used as a predictive factor in the future.

Correlation between glucose metabolism parameters derived from FDG and tumor TNM stages and metastasis-associated proteins in colorectal carcinoma patients

Background

The aim of this study was to investigate the relationship between multiple metabolism parameters derived from FDG and tumor TNM stages as well as tumor metastasis-associated protein of GLUT-1 and MACC1 in colorectal carcinoma (CRC).

Methods

Thirty-eight patients (24 males and 14 females) with primary CRC confirmed by elective surgery pathological, who also accepted ¹⁸F-FDG PET/CT scans during 2017 to 2019 were included in this study. The tumor classification of T, N and M is explained by the 7th American Joint Committee on Cancer (AJCC). ¹⁸F-FDG parameters of SUVmax, SUVmean, TLG and MTV were measured by drawing a region of interest on the primary lesions. The expression of GLUT-1 and MACC1 was quantified by immunohistochemical, and the correlation between metabolism parameters and tumor biomarkers were analyzed.

Results

According to our analysis, the ¹⁸F-FDG parameters of SUVmean was significantly correlated with tumor M status (P = 0.000) of primary CRC. The primary tumor lesion with higher SUVmax, TLG and MTV values prone to a high-T status (P = 0.002, 0.002 and 0.001, respectively). The high expression of GLUT-1/MACC1 weas more frequently involved with T3–4 stage and was poorly differentiated in CRC patients. Multivariate analysis found that the expression of GLUT-1 protein was correlated with SUVmax and MTV (R² = 0.42, P = 0.013 and 0.004, respectively), moreover, the expression of MACC1 protein was correlated with TLG (R² = 0.372, P = 0.000).

Conclusion

Glucose metabolism parameters derived from FDG provides a noninvasive assessment of M status and T status in CRC patients. The expression of GLUT-1 and MACC1 was associated with ¹⁸F-FDG uptake in CRC patients.

Targeting of lipid metabolism with a metabolic inhibitor cocktail eradicates peritoneal metastases in ovarian cancer cells

Ovarian cancer is an intra-abdominal tumor in which the presence of ascites facilitates metastatic dissemination, and associated with poor prognosis. However, the significance of metabolic alterations in ovarian cancer cells in the ascites microenvironment remains unclear. Here we show ovarian cancer cells exhibited increased aggressiveness in ascites microenvironment via reprogramming of lipid metabolism. High lipid metabolic activities are found in ovarian cancer cells when cultured in the ascites microenvironment, indicating a metabolic shift from aerobic glycolysis to β-oxidation and lipogenesis. The reduced AMP-activated protein kinase (AMPK) activity due to the feedback effect of high energy production led to the activation of its downstream signaling, which in turn, enhanced the cancer growth. The combined treatment of low toxic AMPK activators, the transforming growth factor beta-activated kinase 1 (TAK1) and fatty acid synthase (FASN) inhibitors synergistically impair oncogenic augmentation of ovarian cancer. Collectively, targeting lipid metabolism signaling axis impede ovarian cancer peritoneal metastases.

[18F]fluorodeoxyglucose-positron emission tomography and glucose-transporter type 1 expression in untreated primary small bowel adenocarcinoma

BACKGROUND

Literature reporting [18F]fluorodexoyglucose positron emission tomography (FDG-PET) of small bowel adenocarcinoma, a rare tumor, is sparse. To assess FDG uptake in small bowel adenocarcinoma, we retrospectively analyzed a large, single-center database and determined the expression of glucose-transporter type 1 (GLUT-1).

METHODS

Screening of PET datasets in the database (N.=28,961 scans) for untreated histologically-confirmed primary small bowel adenocarcinoma revealed evaluable PET datasets for eight patients. Maximum and peak standardized uptake values (SUV<inf>max</inf> and SUV<inf>peak</inf>, respectively) were calculated via volume-of-interest (VOI) analysis. Additionally, GLUT-1 expression on tumor specimens was prospectively immunohistochemically assessed.

RESULTS

All primary tumors showed high FDG uptake: mean SUVmax was 9.5±2.6 (range: 5.0-13.0) and SUVpeak, 8.1±2.3 (range: 3.9-10.7). Corresponding biopsy specimens (N.=7) demonstrated high GLUT-1 expression.

CONCLUSIONS

Primary small bowel adenocarcinomas have a high GLUT-1 expression. Tumor lesions consistently demonstrated high FDG uptake pre-treatment, suggesting FDG-PET utility in staging and follow-up of these tumors.

Associations between GLUT expression and SUV values derived from FDG-PET in different tumors-A systematic review and meta analysis

PURPOSE

Fluorodeoxyglucose-Positron-emission tomography (FDG-PET), quantified by standardized uptake values (SUV), is one of the most used functional imaging modality in clinical routine. It is widely acknowledged to be strongly associated with Glucose-transporter family (GLUT)-expression in tumors, which mediates the glucose uptake into cells. The present systematic review sought to elucidate the association between GLUT 1 and 3 expression with SUV values in various tumors.

METHODS

MEDLINE library was screened for associations between FDG-PET parameters and GLUT correlation cancer up to October 2018.

RESULTS

There were 53 studies comprising 2291 patients involving GLUT 1 expression and 11 studies comprising 405 patients of GLUT 3 expression. The pooled correlation coefficient for GLUT 1 was r = 0.46 (95% CI 0.40-0.52), for GLUT 3 was r = 0.35 (95%CI 0.24-0.46). Thereafter, subgroup analyses were performed. The highest correlation coefficient for GLUT 1 was found in pancreatic cancer r = 0.60 (95%CI 0.46-0.75), the lowest was identified in colorectal cancer with r = 0.21 (95% CI -0.57-0.09).

CONCLUSION

An overall only moderate association was found between GLUT 1 expression and SUV values derived from FDG-PET. The correlation coefficient with GLUT 3 was weaker. Presumably, the underlying mechanisms of glucose hypermetabolism in tumors are more complex and not solely depended on the GLUT expression.

Construction of a GLUT-1 and HIF-1α gene knockout cell model in HEp-2 cells using the CRISPR/Cas9 technique

Background

Glucose transporter (GLUT)-mediated glucose uptake is an important process in the development of laryngeal carcinoma, one of the most common malignancies of the head and neck. GLUT-1, together with HIF-1α, is also an indicator of hypoxia. Both proteins play a critical role in glucose uptake and glycolysis in laryngeal carcinoma cells under hypoxic stress. A double gene knockout model in which HIF-1α and GLUT-1 are no longer expressed can provide important information about carcinogenesis in laryngeal carcinoma.

Purpose

In this study we used the CRISPR/Cas 9 system to induce HIF-1α and GLUT-1 double gene knockout in HEp-2 cells and then used the knocked-out cells to study the role of these markers in laryngeal carcinoma, including in chemoradioresistance.

Methods

High-grade small-guide RNAs (sgRNAs) of HIF-1α and GLUT-1 were designed using an online tool and inserted into the pUC57-T7-gRNA vector. The recombinant plasmids were transfected into HEp-2 cells and positive cells were screened using the dilution method. Gene mutation and expression were determined by sequence analysis and immunoblotting.

Results

In HIF-1α and GLUT-1 double gene knockout HEp-2 cells, a 171-bp deletion in the HIF-1α genomic sequence was detected, whereas multiple base insertions resulted in frameshift mutations in the GLUT-1 gene. Neither HIF-1α nor GLUT-1 protein was expressed in positive cells. The proliferation, migration, and invasion of HEp-2 cells were significantly decreased afterward. The possible mechanism may be that the inhibition PI3K/AKT/mTOR pathway by HIF-1α and GLUT-1 double gene knockout using CRISPR/Cas9 technique lead to reduction of glucose uptake and lactic acid generation.

Conclusion

Our HIF-1α and GLUT-1 double gene knockout HEp-2 cell model, obtained using a CRISPR/Cas9-based system, may facilitate studies of the pathogenesis of laryngeal carcinoma.

Cancer-associated fibroblasts enhance tumor 18F-FDG uptake and contribute to the intratumor heterogeneity of PET-CT

Purpose: Elevated glucose uptake is a hallmark of cancer. Fluorodeoxyglucose (FDG) uptake was believed to indicate the aggressiveness of tumors and the standardized uptake value (SUV) is a well-known measurement for FDG uptake in positron emission tomography-computed tomography (PET/CT). However, the SUV is variable due to the heterogeneity of tumors. Methods: 126 patients with colorectal cancer underwent ¹⁸F-FDG PET/CT scanning before surgery between Jan 2011 and April 2016. Cancer-associated fibroblast (CAF) densities were calculated with the inForm Advanced image analysis software and were comparatively analyzed between patients with high and low maximum SUV (SUVmax-high and SUVmax-low). Glucose uptake was evaluated in induced and isolated CAFs and CAF-cocultured colon cancer HCT116 cells. Moreover, micro-PET/CT was performed on xenografted tumors and autoradiography was performed in the AOM/DSS induced colon cancer model. Results: CAFs were glycolytic, evidenced by glucose uptake and upregulated HK2 expression. Compared to non-activated fibroblasts (NAFs), CAFs were more dependent on glucose and sensitive to a glycolysis inhibitor. CAFs increased the SUVmax in xenograft tumors and spontaneous colon cancers. Moreover, multivariate analysis revealed that the SUVmax was only associated with tumor size among conventional parameters in colon cancer patients (126 cases, p = 0.009). Besides tumor size, the CAF density was the critical factor associated with SUVmax and outcome, which was 2.27 ± 0.74 and 1.68 ± 0.45 in the SUVmax-high and the SUVmax-low groups, respectively (p = 0.014). Conclusion: CAFs promote tumor progression and increase SUVmax of ¹⁸F-FDG, suggesting CAFs lead to the intratumor heterogeneity of the SUV and the SUVmax is a prognostic marker for cancer patients.

Elevated tumor-to-liver uptake ratio (TLR) from 18F-FDG-PET/CT predicts poor prognosis in stage IIA colorectal cancer following curative resection

Purpose

The prognostic value of the tumor-to-liver uptake ratio (TLR) from 18-fluoro-2-deoxyglucose positron emission tomography/computed tomography (¹⁸F–FDG-PET/CT) in the early stage of colorectal cancer (CRC) is unclear. Notably, some stage IIA CRC patients experience early recurrence even after curative resection and might benefit from neoadjuvant or adjuvant chemotherapy. This study aims to evaluate whether elevated TLR from ¹⁸F–FDG-PET/CT can predict poor prognosis in stage IIA CRC patients undergoing curative resection.

Methods

From April 2010 to December 2013, 504 consecutive CRC patients with different TNM stages (I-IV) underwent ¹⁸F–FDG-PET/CT scans at the 6th Affiliated Hospital of Sun Yat-Sen University. Among the patients, 118 with stage IIA CRC who accepted preoperative ¹⁸F–FDG-PET/CT scanning and were treated with curative surgery alone were reviewed retrospectively. The maximum standardized uptake value (SUVmax) in the primary tumor, TLR, and demographic, clinical, histopathological, and laboratory data were analyzed. Receiver operating characteristic (ROC) curve, univariate and multivariate analyses were performed to identify prognostic factors associated with patient disease-free survival (DFS) and overall survival (OS).

Results

ROC curve analysis demonstrated that TLR was superior to primary tumor SUVmax in predicting the risk of recurrence in stage IIA CRC. The optimal TLR cutoff was 6.2. Univariate analysis indicated that elevated TLR, tumor size, and lymphovascular/neural invasion correlated with DFS (P = 0.001, P = 0.002, and P = 0.001, respectively) and OS (P = 0.001, P = 0.003, and P < 0.001, respectively). The 1-, 3-, and 5-year DFS rates were 98.4%, 96.9%, and 96.9% for stage IIA CRC patients with lower TLR (≤6.2) versus 77.8%, 60.6%, and 60.6% for those with elevated TLR (>6.2), respectively. The 1-, 3-, and 5-year OS rates were 100.0%, 100.0%, and 98.3% for the patients with lower TLR versus 98.1%, 83.3%, and 74.3% for those with elevated TLR. Cox regression analysis showed that elevated TLR [>6.2; hazard ratio (HR): 3.109–57.463; P < 0.001] and tumor size (>4.4 cm; HR: 1.636–19.155; P = 0.006) were independent risk factors for DFS. Meanwhile, elevated TLR (>6.2; HR: 1.398–84.945; P = 0.023) and lymphovascular/neural invasion (positive; HR: 1.278–12.777; P = 0.017) were independent risk factors for OS.

Conclusion

Elevated TLR predicted worse DFS and OS for stage IIA CRC patients and might serve as a potential radiological index to identify candidates for neoadjuvant or adjuvant chemotherapy. Stage IIA CRC patients with elevated TLR should be monitored carefully for early detection of possible recurrence.

Prognostic value of positron emission tomography/computed tomography for adjuvant chemotherapy of colon cancer

BACKGROUND

To assess the prognostic value of preoperative ¹⁸ F-fluorodeoxyglucose positron emission tomography/computed tomography in patients with high-risk stage II or stage III colon cancer who underwent FOLFOX chemotherapy.

METHODS

The study included 166 patients with high-risk stage II or stage III colon cancer who received FOLFOX4 chemotherapy. Retrospective patient data were analysed including pathological stage, histology, disease-free survival (DFS) and the maximum standardized uptake value (SUV_max ) of the primary tumour on ¹⁸ F-fluorodeoxyglucose positron emission tomography/computed tomography. The primary end point was DFS.

RESULTS

There were recurrences in 29 of the 166 patients (17.4%). Measuring the area under the receiver operating characteristic curve, the cut-off value of SUV_max with maximum sensitivity and specificity was 10.95. Using the Kaplan-Meier method, the DFS of the patients categorized by SUV_max tended to differ (P = 0.055). In univariate analyses, the risk factors for DFS were age over 70 years, higher N stage and neural invasion. SUV_max ≤ 10.95 showed a tendency, but was not significant (P = 0.0604). In multivariate analyses, the risk factors for DFS were age over 70 and neural invasion.

CONCLUSIONS

The results of this study suggest that high fluorodeoxyglucose uptake of the primary mass in high-risk stage II and stage III colon cancer does not significantly correlate with DFS.

SLC2A1/GLUT1 expression in mural nodules of intraductal papillary mucinous neoplasm of the pancreas

In intraductal papillary mucinous neoplasms (IPMNs), the presence of a mural nodule showing a papillary or nodular proliferation of tumor cells in the dilated pancreatic duct is an indication for resection of IPMN. Solute carrier family 2, facilitated glucose transporter member 1, known as glucose transporter type 1 (SLC2A1/GLUT1) mediates cellular glucose uptake in many carcinomas and is correlated with increased ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) uptake. We examined SLC2A1/GLUT1 expression in the mural nodules of 180 IPMN specimens to distinguish malignant/benign tumors. A mural nodule was detected in 80 (44.4%) of the IPMNs, and was detected in 18.6% (13/70) of the IPMN-low (dysplasia) specimens, 36.1% (13/36) of the IPMN-int, 93.3% (28/30) of the IPMN-high, and 59.1% (26/44) of the IPMN-inv (with an associated invasive carcinoma) specimens. The sensitivity for detecting mural nodules was 81.7% by endoscopic ultrasonography, 70% by contrast-enhanced computed tomography and 54% by endoscopic retrograde cholangiopancreatography. SLC2A1/GLUT1 expression in the mural nodules was recognized in the basal and basolateral cytomembrane of tumor cells and was expressed in 15.4% (2/13) of the IPMN-low, 15.4% (2/13) of the IPMN-int, 71.4% (20/28) of the IPMN-high and 84.6% (22/26) of the IPMN-inv groups. The SLC2A1/GLUT1 expression was significantly higher in the IPMN-high and IPMN-inv mural nodules than in those of the IPMN-low and IPMN-int groups. Our findings suggest that SLC2A1/GLUT1 is expressed late in the adenoma-carcinoma sequence during carcinogenesis in IPMN, and SLC2A1/GLUT1 act as therapeutic target for malignant IPMN.

Insulin-IGF signaling affects cell transformation in the BALB/c 3T3 cell model

The increased cancer mortality of diabetes type 2 patients is most likely an evidence of the tight connection between tumor development and energy metabolism. A major focus of today's research is still the identification of key proteins of both diseases and the development of corresponding inhibitors. In this study we combined the two-stage BALB/c-3T3 cell transformation assay (BALB-CTA) with the IR/IGF-1R inhibitor OSI-906 (linsitinib) and analyzed alterations in protein activity and energy parameters in non-transformed as well as transformed cells. OSI-906 successfully inhibited the phosphorylation of IR/IGF-1R and decreased cell growth in non-transformed cells. In the BALB-CTA, a permanent treatment with OSI-906 reduced cellular transformation dose-dependently, whereas a temporary treatment gave evidence for a preventive effect in the promotion phase. Furthermore, even though several key proteins were affected, it was possible to show that the phosphorylation of GSK3, Erk 1/2 and the S6 protein are not crucial for the cell foci reducing effect of OSI-906. Taken together, the BALB-CTA confirmed results of OSI-906 from animal studies and enhanced the knowledge of its mode of action. Therefore, the BALB-CTA offers the opportunity to analyze alterations in the transformation process more precisely and will be helpful to identify effective cancer treatments.

Facilitative glucose transporters: Implications for cancer detection, prognosis and treatment

It is long recognized that cancer cells display increased glucose uptake and metabolism. In a rate-limiting step for glucose metabolism, the glucose transporter (GLUT) proteins facilitate glucose uptake across the plasma membrane. Fourteen members of the GLUT protein family have been identified in humans. This review describes the major characteristics of each member of the GLUT family and highlights evidence of abnormal expression in tumors and cancer cells. The regulation of GLUTs by key proliferation and pro-survival pathways including the phosphatidylinositol 3-kinase (PI3K)-Akt, hypoxia-inducible factor-1 (HIF-1), Ras, c-Myc and p53 pathways is discussed. The clinical utility of GLUT expression in cancer has been recognized and evidence regarding the use of GLUTs as prognostic or predictive biomarkers is presented. GLUTs represent attractive targets for cancer therapy and this review summarizes recent studies in which GLUT1, GLUT3, GLUT5 and others are inhibited to decrease cancer growth.

Relationship between Preoperative ¹⁸F-Fluorodeoxyglucose Uptake and Epidermal Growth Factor Receptor Status in Primary Colorectal Cancer

PURPOSE

Both ¹⁸F-fluorodeoxyglucose (¹⁸F-FDG) uptake and epidermal growth factor receptor (EGFR) status are prognostic variables of colorectal cancer (CRC). The aim of this study was to investigate a possible association between ¹⁸F-FDG uptake on preoperative positron emission tomography/computed tomography (PET/CT) and EGFR status in primary CRC.

MATERIALS AND METHODS

Records of 132 patients (66 men and 66 women; mean age=67.1±11.1 years) who underwent ¹⁸F-FDG PET/CT for CRC staging and subsequent bowel resection were reviewed. In primary lesions, ¹⁸F-FDG uptake was semiquantitatively evaluated in terms of maximum standardized uptake value (SUVmax), and EGFR status was determined by immunohistochemistry. Associations of clinicopathological parameters and EGFR status were analyzed by Pearson's chi-square test, multiple logistic regression, and receiver operating characteristic curves.

RESULTS

Eighty-six patients (65.2%) showed EGFR expression. SUVmax was significantly lower in EGFR-negative tumors than in EGFR-expressing tumors (10.0±4.2 vs. 12.1±2.1; p=0.012). It was the only significant parameter correlated with EGFR expression (odds ratio=2.457; relative risk=2.013; p=0.038). At the SUVmax threshold of 7.5, the sensitivity and specificity for predicting EGFR expression were 84.9% and 40.4%, respectively (area under the curve=0.624; p=0.019).

CONCLUSION

Preoperative ¹⁸F-FDG uptake is slightly correlated with EGFR status in primary CRC. Preoperative SUVmax of ¹⁸F-FDG may have a limited role in predicting EGFR expression in such tumors because of its poor specificity.

Glucose transporter isoform 1 expression enhances metastasis of malignant melanoma cells

The glucose transporter isoform 1 (GLUT1; SLC2A1) is a key rate-limiting factor in the transport of glucose into cancer cells. Enhanced GLUT1 expression and accelerated glycolysis have been found to promote aggressive growth in a range of tumor entities. However, it was unknown whether GLUT1 directly impacts metastasis. Here, we aimed at analyzing the expression and function of GLUT1 in malignant melanoma. Immunohistochemical analysis of 78 primary human melanomas on a tissue micro array showed that GLUT1 expression significantly correlated with the mitotic activity and a poor survival. To determine the functional role of GLUT1 in melanoma, we stably suppressed GLUT1 in the murine melanoma cell line B16 with shRNA. GLUT1 suppressed melanoma cells revealed significantly reduced proliferation, apoptosis resistance, migratory activity and matrix metalloproteinase 2 (MMP2) expression. In a syngeneic murine model of hepatic metastasis, GLUT1-suppressed cells formed significantly less metastases and showed increased apoptosis compared to metastases formed by control cells. Treatment of four different human melanoma cell lines with a pharmacological GLUT1 inhibitor caused a dose-dependent reduction of proliferation, apoptosis resistance, migratory activity and MMP2 expression. Analysis of MAPK signal pathways showed that GLUT1 inhibition significantly decreased JNK activation, which regulates a wide range of targets in the metastatic cascade. In summary, our study provides functional evidence that enhanced GLUT1 expression in melanoma cells favors their metastatic behavior. These findings specify GLUT1 as an attractive therapeutic target and prognostic marker for this highly aggressive tumor.

Relationship between 18-F-fluoro-deoxy-D-glucose uptake and expression of glucose transporter 1 and pyruvate kinase M2 in intrahepatic cholangiocarcinoma

BACKGROUND

Cholangiocellular carcinoma is characterized by elevated glucose consumption, resulting in an increased uptake of 18F-2-fluoro-2-deoxy-d-glucose (18F-FDG). This study investigates the relationship between 18F-FDG uptake and tumour glucose metabolism.

METHODS

This was a retrospective analysis of 19 patients with cholangiocellular carcinoma. Immunohistochemistry for glucose transporter 1 and pyruvate kinase type M2 were performed. Overall tumour glucose metabolism was evaluated by measuring 18F-FDG uptake and the protein expression levels of glucose transporter 1 and pyruvate kinase type M2.

RESULTS

18F-FDG uptake had a strong positive correlation with histological differentiation. Both tumour status (p=0.044) and tumour size (p=0.011) were correlated with primary tumour 18F-FDG uptake. Glucose transporter 1 expression correlated with histological differentiation (p=0.017), while pyruvate kinase type M2 expression tended to correlate with lymph node metastasis (p=0.051). Glucose transporter 1 expression was strongly related to the standard uptake value (p=0.001), but that of pyruvate kinase type M2 was not (p=0.461).

CONCLUSIONS

Glucose transporter 1 expression exhibits a strong correlation with 18F-FDG uptake in cholangiocellular carcinoma tissue, while pyruvate kinase type M2 expression was not associated with fluoro-2-deoxy-d-glucose uptake. In addition to its glycolytic function, pyruvate kinase type M2 has a variety of roles and its expression may enhance tumour cell invasion and promote the lymph node metastasis of intrahepatic cholangiocarcinoma.

The value of liver-based standardized uptake value and other quantitative 18F-FDG PET-CT parameters in neoadjuvant therapy response in patients with locally advanced rectal cancer: correlation with histopathology

AIM

We aimed to investigate the value of PET-CT in therapy response and the correlation of quantitative PET parameters with histopathologic results in patients with locally advanced rectal cancer (LARC) before and after neoadjuvant chemoradiotherapy. We also analyzed the correlation of PET-CT parameters between Ki-67 and glucose transporter 1 (GLUT1).

PATIENTS AND METHODS

A total of 29 patients diagnosed with LARC who had undergone a biopsy between 2009 and 2012 were included in our study. Quantitative PET parameters [standardized uptake value (SUV)max-mean, lean body mass SUV(max-mean), tumor/liver SUV, retention index , and [INCREMENT]SUV(max)] were measured before and after therapy using PET-CT. Tumor regression grade (TRG) was evaluated according to Wheeler's classification. Patients in grade 1 were considered responders, whereas patients at grades 2 and 3 were considered nonresponders. Immunohistochemical staining with Ki-67 and GLUT1 was performed on biopsy and surgical specimens. The correlation between staining ratios and SUV was also investigated.

RESULTS

SUV parameters were significantly decreased after therapy (P < 0.001). Twelve (41%) patients were at TRG1, 10 (35%) were at TRG2, and seven (24%) were at TRG3. A cutoff SUV(max) of 5.05 to discriminate between responders and nonresponders after treatment revealed a sensitivity of 57%, specificity of 73%, negative predictive value of 65%, positive predictive value of 67%, and accuracy of 66%. Using a cutoff of 3.55 for the SUV(mean) (standardized measurement of SUV with 1.2-cm-diameter region of interest) revealed a sensitivity, specificity, negative predictive value, positive predictive value, and accuracy of 67, 76, 67, 76, and 72%, respectively. For a cutoff of 1.95 for the tumor SUV(mean)/liver SUV(mean), these diagnostic values after therapy were 73, 78, 82, 67, and 76%, respectively. We found a moderate correlation between liver-based SUV(max) (r = -0.35, P = 0.019) and SUV(mean )(r = -0.31, P = 0.036) with GLUT1 after therapy. Quantitative PET parameters and retention index were moderately correlated with Ki-67.

CONCLUSION

PET-CT is a useful method for assessing the response to neoadjuvant chemoradiotherapy in patients with LARC. The most significant parameter for assessing treatment response using SUV parameters is the tumor/liver ratio.

Expression and significance of glucose transporter-1, P-glycoprotein, multidrug resistance-associated protein and glutathione S-transferase-π in laryngeal carcinoma

Increasing glucose transporter-1 (GLUT-1) activity is one of the most important ways to increase the cellular influx of glucose. We previously demonstrated that increased GLUT-1 expression was an independent predictor of survival in patients with laryngeal carcinoma. Thus, GLUT-1 may present a novel therapeutic target in laryngeal carcinoma. In this study, the expression of GLUT-1, P-glycoprotein (P-gp), multidrug resistance-associated protein 1 (MRP1) and glutathione S-transferase-π (GST-π) in laryngeal carcinomas was investigated by immunohistochemistry. Additionally, possible correlations between GLUT-1 and P-gp, MRP1 and GST-π and various clinicopathological parameters were analyzed. In this study, 52.9% (18/34), 58.8% (20/34), 20.6% (7/34) and 58.8% (20/34) of the laryngeal carcinomas were positive for GLUT-1, P-gp, MRP1 and GST-π, respectively. The expression of GLUT-1, P-gp, MRP1 and GST-π was higher in laryngeal carcinoma specimens when compared with laryngeal precancerous lesions (P<0.05). Pearson’s correlation analysis showed correlations between GLUT-1 and P-gp (r=0.364; P=0.034), GLUT-1 and MRP1 (r=0.359; P=0.037) and P-gp and GST-π (r=0.426; P=0.012). GLUT-1 expression was found to significantly correlate with tumor-node-metastasis classification (P=0.02) and clinical stage (P=0.037). Furthermore, P-gp was found to significantly correlate with clinical stage (P=0.026). Univariate analysis showed that MRP1 expression was significantly associated with poor survival (c²=5.16; P=0.023). Multivariate analysis revealed that lymph node metastasis (P=0.009) and MRP1 overexpression (P=0.023) were significant predictors of poor survival. In the present study, the expression of GLUT-1, P-gp, MRP1 and GST-π in laryngeal carcinomas was investigated, as well as the correlations between these proteins. P-gp was found to significantly correlate with clinical stage, while MRP1 overexpression was significantly associated with poor survival.

Metastatic hepatocarcinoma he/de tumor model in rat

The aim of this study is to select among potential tumor models that could be suitable to follow the metastatic spead of tumor cells. (18)FDG-PET tumor diagnostic test has been adapted to investigate tumor growth in vivo in local and metastatic rat models. Materials and Methods. The expression of glucose transporters was traced by immunohistological analysis, followed by the uptake of (18)FDG and visualized by MiniPET scanner. After s.c. administration of hepatocarcinoma (He/De) cells intensive local tumor growth and (18)FDG uptake were measured.

RESULTS

Whole body (18)FDG-PET imaging supported by histological analysis have shown that subcutaneously growing tumors did not project metastases to other sites from the injected area. To avoid local tumor formation i.v. injection was chosen, but did not improve the safety of tumor cell administration. Tumor formation after i.v. injection took a longer time than after s.c. administration. Tumors upon i.v. generation were smaller and detectable in liver and lung, but not in other organs or tissues. iii) Subrenally implanted He/De cells spread from the retroperitoneal primary tumor of the kidney to thoracal paratymic lymph nodes (PTNs). The spread from primary site to metastatic tumors in PTNs was confirmed by post mortem surgery and histological examinations.

CONCLUSION

Among the three methods applied: a) Local s.c. administration of tumor cells generated local tumors unsuitable to study metastasis. b) Intravenous administration causing unpredicatable location of tumor formation is not regarded a reliable metastatic tumor model. c) Subreanal implantation model proved to be a suitable model to follow the metastatic process in rats.

Aspirin may modify tumor microenvironment via antiplatelet effect

High-quality evidence suggests that aspirin is a promising agent for cancer prevention and treatment. Direct inhibition of cyclooxygenase-2 (COX-2) pathway is generally thought to be the main mechanism by which aspirin inhibits cancer development. However, either pharmacological properties of aspirin or recent results of epidemiologic studies do not support that mechanism. To address this inconsistency, we hypothesize that antiplatelet effect of aspirin via inhibition of COX-1 may be one of potential mechanisms to inhibit carcinogenesis. Aberrant platelet activation will lead to promote hostility of tumor microenvironment by releasing an abundant array of angiogenesis regulators. Given the outstanding ability of antiplatelet, aspirin may restore balance of pro- and anti-angiogenic factors released from platelet to "normalize" tumor vasculature and shape tumor microenvironment to some extent, which will not only diminish tumor aggressiveness and progression, but also enhance the sensitivity to therapeutic treatment. Thus, targeting the platelet activation leading to alter tumor microenvironment may provide a novel way to tumor therapy.

Non-FDG-avid primary papillary thyroid carcinoma may not differ from FDG-avid papillary thyroid carcinoma

BACKGROUND

FDG (2-[(18)F]Fluoro-2-D-deoxyglucose-positron emission tomography (PET)/computed tomography (CT), which can detect a change in glucose metabolism in cancer cells, has been introduced as a diagnostic and prognostic tool in papillary thyroid carcinoma (PTC). However, differences in the clinicopathological and biological characteristics between primary PTCs with FDG uptake and those without FDG uptake are not well established.

METHODS

A total of 188 patients with PTC who had preoperative PET/CT scans were enrolled to compare the differences of clinicopathological parameters between FDG-avid (F-PTC; n = 150) and non-FDG-avid tumors (FN-PTC; n = 38). Immunohistochemical staining for glucose transporter (GLUT)-1 and hypoxia-inducible factor-1 alpha (HIF-1α) was performed.

RESULTS

FN-PTCs were smaller; had a lower incidence of lymphatic invasion, vascular invasion, multifocality, and central lymph node metastasis; and had a lower maximum standardized uptake value than F-PTCs. After exclusion of high-risk patients for recurrence, FN-PTCs remained smaller (p < 0.001) and had less lymphatic invasion (p = 0.061). Among tumors larger than the spatial resolution of the PET/CT scan, macrocalcification was more frequent in FN-PTC than in F-PTC (p = 0.043). While FN-PTC and F-PTC showed no difference in GLUT-1 expression (50% vs. 75%, p = 0.363), FN-PTC showed lower HIF-1α immunoreactivity than F-PTC (25.0% vs. 75.0%, p = 0.032).

CONCLUSION

Tumor size and macrocalcification are clinicopathological differences between FN-PTC and F-PTC. Biologically, HIF-1α may be responsible for increased FDG uptake in PTC.

Gene Expression of Glucose Transporter 1 (GLUT1), Hexokinase 1 and Hexokinase 2 in Gastroenteropancreatic Neuroendocrine Tumors: Correlation with F-18-fluorodeoxyglucose Positron Emission Tomography and Cellular Proliferation

Neoplastic tissue exhibits high glucose utilization and over-expression of glucose transporters (GLUTs) and hexokinases (HKs), which can be imaged by ¹⁸F-Fluorodeoxyglucose-positron emission tomography (FDG-PET). The aim of the present study was to investigate the expression of glycolysis-associated genes and to compare this with FDG-PET imaging as well as with the cellular proliferation index in two cancer entities with different malignant potential. Using real-time PCR, gene expression of GLUT1, HK1 and HK2 were studied in 34 neuroendocrine tumors (NETs) in comparison with 14 colorectal adenocarcinomas (CRAs). The Ki67 proliferation index and, when available, FDG-PET imaging was compared with gene expression. Overexpression of GLUT1 gene expression was less frequent in NETs (38%) compared to CRAs (86%), P = 0.004. HK1 was overexpressed in 41% and 71% of NETs and CRAs, respectively (P = 0.111) and HK2 was overexpressed in 50% and 64% of NETs and CRAs, respectively (P = 0.53). There was a significant correlation between the Ki67 proliferation index and GLUT1 gene expression for the NETs (R = 0.34, P = 0.047), but no correlation with the hexokinases. FDG-PET identified foci in significantly fewer NETs (36%) than CRAs (86%), (P = 0.04). The gene expression results, with less frequent GLUT1 and HK1 upregulation in NETs, confirmed the lower metabolic activity of NETs compared to the more aggressive CRAs. In accordance with this, fewer NETs were FDG-PET positive compared to CRA tumors and FDG uptake correlated with GLUT1 gene expression.

Anti-cancer activity of anti-GLUT1 antibody-targeted polymeric micelles co-loaded with curcumin and doxorubicin

BACKGROUND

Treatment of late stage cancers has proven to be a very difficult task. Targeted therapy and combinatory drug administration may be the solution.

PURPOSE

The study was performed to evaluate the therapeutic efficacy of PEG-PE micelles, co-loaded with curcumin (CUR) and doxorubicin (DOX), and targeted with anti-GLUT1 antibody (GLUT1) against HCT-116 human colorectal adenocarcinoma cells both in vitro and in vivo.

METHODS

HCT-116 cells were treated with non-targeted and GLUT1-targeted CUR and DOX micelles as a single agent or in combination. Cells were inoculated in female nude mice. Established tumors were treated with the micellar formulations at a dose of 4 mg/kg CUR and 0.4 mg/kg DOX every 2 d for a total of 7 injections.

RESULTS

CUR + DOX-loaded micelles decorated with GLUT1 had a robust killing effect even at low doses of DOX in vitro. At the doses chosen, non-targeted CUR and CUR + DOX micelles did not exhibit any significant tumor inhibition versus control. However, GLUT1-CUR and GLUT1-CUR + DOX micelles showed a significant tumor inhibition effect with an improvement in survival.

CONCLUSION

We showed a dramatic improvement in efficacy between the non-targeted and GLUT1-targeted formulations both in vitro and in vivo. Hence, we confirmed that GLUT1-CUR + DOX micelles are effective and deserve further investigation.

An evaluation of 2-deoxy-2-[18F]fluoro-D-glucose and 3'-deoxy-3'-[18F]-fluorothymidine uptake in human tumor xenograft models

PURPOSE

The aim of this study is to assess the variability of 2-deoxy-2-[(18)F]fluoro-D: -glucose ([(18)F]-FDG) and 3'-deoxy-3'-[(18)F]-fluorothymidine ([(18)F]-FLT) uptake in pre-clinical tumor models and examine the relationship between imaging data and related histological biomarkers.

PROCEDURES

[(18)F]-FDG and [(18)F]-FLT studies were carried out in nine human tumor xenograft models in mice. A selection of the models underwent histological analysis for endpoints relevant to radiotracer uptake. Comparisons were made between in vitro uptake, in vivo imaging, and ex vivo histopathology data using quantitative and semi-quantitative analysis.

RESULTS

In vitro data revealed that [1-(14)C]-2-deoxy-D: -glucose ([(14)C]-2DG) uptake in the tumor cell lines was variable. In vivo, [(18)F]-FDG and [(18)F]-FLT uptake was highly variable across tumor types and uptake of one tracer was not predictive for the other. [(14)C]-2DG uptake in vitro did not predict for [(18)F]-FDG uptake in vivo. [(18)F]-FDG SUV was inversely proportional to Ki67 and necrosis levels and positively correlated with HKI. [(18)F]-FLT uptake positively correlated with Ki67 and TK1.

CONCLUSION

When evaluating imaging biomarkers in response to therapy, the choice of tumor model should take into account in vivo baseline radiotracer uptake, which can vary significantly between models.

Prognostic value of 18-fluorodeoxyglucose positron emission tomography-computed tomography in resectable colorectal cancer

AIM: To assess the prognostic value of preoperative 18 fluorodeoxyglucose positron emission tomography (FDG-PET)/computed tomography (CT) in patients with resectable colorectal cancer.

METHODS: One hundred sixty-three patients with resectable colorectal cancer who underwent FDG-PET/CT before surgery were included. Patient data including pathologic stage at presentation, histology, treatment, disease-free survival and the maximum standardized uptake value (SUVmax) of the primary tumor on FDG-PET/CT were retrospectively analyzed. Median follow up duration was 756 (range, 419-1355). The primary end point was disease-free survival.

RESULTS: Twenty-five of 163 patients (15.3%) had recurrences. The median SUVmax values of the recurrence and no-recurrence groups were 8.9 (range, 5-24) and 8.2 (range, 0-23, P = 0.998). Receiver operating characteristic (ROC) curve analysis showed no significant association between SUVmax and recurrence (area under the curve = 0.5, P = 0.998, 95% CI: 0.389-0.611). Because a statistically significant value was not found, SUVmax was dichotomized at its median of 8.6. The disease-free survival curve was analyzed using the median SUVmax (8.6) as the cut off. Univariate and multivariate analysis did not provide evidence that disease-free survival rates for the subgroups defined by the median SUVmax were significantly different (P = 0.52, P = 0.25).

CONCLUSION: Our study suggests that the high FDG uptake of primary mass in resectable colorectal cancer doesn’t have a significant relationship with tumor recurrence and disease-free survival.

Expression and significance of hypoxia-inducible factor-1α and glucose transporter-1 in laryngeal carcinoma

Malignant cells show increased glucose uptake in vitro and in vivo. This process is considered to be mediated by glucose transporters (GLUTs). Hypoxia-inducible factor-1α (HIF-1α) may upregulate GLUT-1 expression. Little is known about the correlation between HIF-1α and GLUT-1 expression in laryngeal carcinoma. The current study investigated this correlation immunohistochemically, according to various clinical and pathological features, in 49 paraffin-embedded archival tissue blocks from patients with laryngeal squamous cell carcinoma. HIF-1α and GLUT-1 expression was detected in 63.3 (31/49) and 55.1% (27/49) of the tumour samples, respectively. HIF-1α expression was significantly correlated with lymph node classification (P=0.018), recurrence (P=0.02) and metastasis (P=0.031). GLUT-1A expression was significantly associated with recurrence (P=0.02) and metastasis (P=0.01). Univariate analyses revealed that HIF-1α (χ(2)=8.2; P=0.004) and GLUT-1 expression (χ(2)=9.0; P=0.003) were significantly associated with a poorer survival rate. In a multivariate analysis, GLUT-1 expression (P=0.006) was a significant predictor of poor survival rate, as well as the primary tumour site, lymph node invasion and distant metastasis. Based on Spearman's analysis, GLUT-1 expression and phosphatidylinositol 3-kinase (PI3K) expression were significantly correlated (r=0.504; P=0.000). This is the first study to demonstrate a significant correlation between GLUT-1 and HIF-1α expression in laryngeal carcinoma and to show increased GLUT-1 expression as an independent survival rate predictor. These results suggest that GLUT-1 is a potential new therapeutic target for laryngeal carcinoma.

Prognostic Significance of Volume-based Metabolic Parameters by (18)F-FDG PET/CT in Gallbladder Carcinoma

PURPOSE

We investigated the prognostic values of volume-based metabolic parameters by (18)F-fluorodeoxyglucose ((18)F-FDG) positron emission tomography (PET)/computed tomography (CT) in gallbladder carcinoma patients and compared them with other prognostic parameters.

MATERIALS AND METHODS

We enrolled 44 patients, who were initially diagnosed with gallbladder carcinoma and undergoing (18)F-FDG PET/CT. Various metabolic volume-based PET parameters of primary tumors, including maximum and average standardized uptake values (SUVmax, SUVavg), metabolic tumor volume (MTV), and total lesion glycolysis (TLG), were measured in gallbladder carcinoma patients using mediastinal blood pool activity as a threshold SUV for determining the tumor boundaries. Overall survival analysis was performed using the Kaplan-Meier method with PET parameters and other clinical variables. For determining independent prognostic factors, Cox proportional hazards regression analysis was performed.

RESULTS

Of the 44 enrolled patients, cancer- or treatment-related death occurred in 30 (68.2 %). The mean clinical follow-up period was 22.2 ± 10.4 m (range, 0.6-35.9 m). Univariate analysis demonstrated that clinical or pathologic TNM stage (P < 0.001), treatment modality (P < 0.001), MTV (cutoff = 135 cm(3), P = 0.001), and TLG (cutoff = 7,090, P < 0.05) were significant prognostic factors. In multivariate analysis, both clinical or pathologic TNM stage [hazard ratio (HR) = 2.019 (I vs II), 21.287 (I vs III), and 24.354 (I vs IV); P = 0.001) and TLG (HR = 2.930; P < 0.05) were independent prognostic factors for predicting overall survival.

CONCLUSIONS

In gallbladder cancer, TLG of the primary tumor, a volume-based metabolic parameter, is a significant independent prognostic factor for overall survival in conjunction with the clinical or pathological TNM stage.

Imaging primary prostate cancer with 11C-Choline PET/CT: relation to tumour stage, Gleason score and biomarkers of biologic aggressiveness

Background

As a significant overlap of 11C-Choline standardized uptake value (SUV) between prostate cancer and benign prostate hyperplasia (BPH) tissue, controversy exists regarding the clinical value of 11C-Choline PET/CT scan in primary prostate cancer. In this study, the SUVmax of the prostate lesions and the pelvic muscles were measured and their ratios (SUVmax-P/M ratio) were calculated. Then we evaluated whether the tracer 11C-Choline uptake, quantified as SUVmax-P/M ratio, correlated with tumour stage, Gleason score, and expression levels of several biomarkers of aggressiveness.

Methods

Twenty-six patients with primary prostate cancer underwent 11C-Choline PET/CT. Tumour specimens from these patients were graded histopathologically, and immunnohistochemistry for Ki-67, CD31, androgen receptor (AR), Her-2/neu, Bcl-2, and PTEN were performed.

Results

Both SUVmax and SUVmax-P/M ratio showed no significant difference between patients with tumour stage II and III, but significantly elevated in patients with tumour stage IV. SUVmax-P/M ratio was also significantly higher in lesions with Gleason score of 4+3 or higher versus less than or equal to 3+4. SUVmax-P/M ratio was found significantly correlated with expression levels of Ki-67 and CD31. In addition, a higher SUVmax-P/M ratio was demonstrated in Her-2/neu positive subgroup than negative subgroup. At the same time, Gleason score and expression levels of these biomarkers showed no significant association with SUVmax.

Conclusions

Using the parameter SUVmax-P/M ratio, 11C-Choline PET/CT may be a valuable non-invasive imaging technology in the diagnosis of primary prostate cancer.

Correlations between SUVmax and expression of GLUT1 and growth factors inducing lymphangiogenesis

RATIONALE AND OBJECTIVES

The purpose of this study was to assess the correlations between the maximum standardized uptake value (SUVmax) of colorectal carcinoma and hepatocyte growth factor (HGF), vascular endothelial growth factor C (VEGF-C), and their respective receptors using (18)F-fluorodeoxyglucose (FDG) positron emission tomography (PET)/computed tomography (CT).

METHODS

Fluorine-18-FDG PET/CT scans were performed on 33 patients with colorectal carcinoma before any treatment. The SUVmax of colorectal carcinoma and the clinicopathologic data associated with lymphatic metastases were analyzed. The expression of glucose transporter 1 (GLUT1), HGF, c-Met, VEGF-C, and vascular endothelial growth factor receptor 3 (VEGFR-3) in tumor tissues was analyzed using immunohistochemical methods. Lymphatic endothelial cells were marked with D2-40, and lymphatic vessel density (LVD) was recorded. The correlations were analyzed among the SUVmax of colorectal carcinoma, LVD, and the expression of GLUT1, HGF, c-Met, VEGF-C, and VEGFR-3 in tumor tissues.

RESULTS

SUVmax and LVD in 15 patients with lymphatic metastases were 13.00 ± 4.51 and 6.25 ± 1.54, respectively, whereas in 18 patients with nonmetastatic nodes, SUVmax and LVD were 9.66 ± 4.82 and 4.54 ± 1.02, respectively. The differences of SUVmax and LVD between metastatic and nonmetastatic patients were statistically significant (F = 4.153, P = .025, and F = 14.501, P = .001, respectively). There were no statistical differences of SUVmax and LVD in variably differentiated colorectal carcinoma (F = 0.708, P = .502, and F = 0.311, P = .735, respectively). The expression rates of GLUT1 in neoplastic and normal tissue were 72.7% (24 of 33) and 21.2% (seven of 33), respectively (P = .001). Moreover, the expression rates of GLUT1 in metastatic and nonmetastatic tissue were 93.33% (14 of 15) and 61.11% (11 of 18), respectively (P = .038). LVD and the integrated optical density of GLUT1 were 5.31 ± 1.53 and 8.21 × 10(4) ± 4.30 × 10(4), respectively, in tumor tissue, and there were linear correlations between SUVmax and LVD (r = 0.373, P = .033) and between SUVmax and expression of GLUT1 (r = 0.428, P = .013). The differences of SUVmax in HGF, c-Met, and VEGF-C groups with different expressions were statistically significant (P = .007, P = .009, and P = .030, respectively). No correlation was found between the expression of VEGFR-3 and SUVmax. The expression of GLUT1 and HGF as well as of GLUT1 and VEGF-C was rank correlated (r = 0.521, P = .002, and r = 0.505, P = .003, respectively). No rank correlations were found between the expression of GLUT1 and c-Met, GLUT1, and VEGFR-3.

CONCLUSIONS

The SUVmax of colorectal carcinoma was significantly higher in metastatic patients; the uptake of colorectal carcinoma was associated with LVD and the expression of HGF and VEGF-C but not with the expression of VEGFR-3.

Molecular mechanism underlying the detection of colorectal cancer by 18F-2-fluoro-2-deoxy-D-glucose positron emission tomography

BACKGROUND

Biological imaging by positron emission tomography (PET) using 18F-2-fluoro-2-deoxy-D-glucose (FDG) has been widely used clinically for the detection of primary tumors and for early prediction of response to chemotherapy. In this study, we examined the molecular mechanism underlying the detection of colorectal cancers by FDG-PET.

MATERIAL AND METHODS

In all, 37 patients with colorectal cancer were examined with FDG-PET, and the maximal standardized uptake value (SUV) was calculated. Using surgical tissue samples, we examined the expression levels of hypoxia-inducible factor alpha (HIF1α), a marker of tissue hypoxia; proliferative cellular nuclear antigen (PCNA), a marker of proliferation; and glucose transporter (GLUT)1 and hexokinase (HK)2, protein of glucose uptake by using reverse transcriptase-polymerase chain reaction.

RESULTS

All except two colorectal cancer lesions showed increased uptake of FDG. The mean SUV of FDG-PET was 12.0 ± 1.2 (±SEM). The mean mRNA expression levels of GLUT1 and HK2 were significantly higher in cancer tissues than in the surrounding normal mucosa. Moreover, to promote the upregulation of glucose uptake, the expressions of HIF1α and PCNA were induced to 2.6 and 3.3 times higher than that in the normal mucosa. However, the quantitative correlation analysis showed SUV was correlated with HIF1α expression but not with PCNA expression.

CONCLUSION

Our molecular-based analysis suggested that FDG accumulation due to induction of glucose uptake proteins might be associated with the hypoxic environment in tumors rather than the tumor growth. Therefore, for assessing the efficacy of chemotherapy using FDG-PET, we must keep in mind that SUV does not indicate the tumor growth directly.

Role of FDG-PET as a biological marker for predicting the hypoxic status of tongue cancer

BACKGROUND

To determine whether 2-[(18)F]fluoro-2-deoxy-D-glucose positron emission tomography (FDG-PET) could serve as a useful technique predicting tumor hypoxia and prognosis in tongue cancer, we assessed the relationship between FDG uptake and the levels of hypoxia-related markers.

METHODS

Tumor uptake of FDG in 33 patients with T2 tongue cancer was assessed by measuring maximum standardized uptake values (SUVmax). Expression of hypoxia-inducible factor (HIF)-1α, carbonic anhydrase (CA)-9, glucose transporter (GLUT)-1, and erythropoietin receptor (EPOR), was determined by immunohistochemical staining. Correlation between SUVmax and the expression of hypoxia-related markers was assessed and multivariate analysis was performed to determine what parameters affected clinical outcomes.

RESULTS

We observed strong correlations between SUVmax and expression of HIF-1α (p < .05), CA-9 (p < .01), and GLUT-1 (p < .01). SUVmax, HIF-1α expression, and tumor grade were significant independent predictors of disease-free survival (DFS).

CONCLUSION

SUVmax may be a good noninvasive biomarker for prediction of hypoxic status and prognosis of patients with T2 tongue cancer.