The cellular response of malignant tumors to hypoxia is diverse. Several important endogenous metabolic markers are upregulated under hypoxic conditions. We examined the staining patterns and ...co-expression of HIF-1α, CAIX, LDH-5, GLUT-1, MCT1 and MCT4 with the exogenous hypoxic cell marker pimonidazole and the association of marker expression with clinicopathological characteristics.
20 biopsies of advanced head and neck carcinomas were immunohistochemically stained and analyzed. All patients were given the hypoxia marker pimonidazole intravenously 2 h prior to biopsy taking. The tumor area positive for each marker, the colocalization of the different markers and the distribution of the markers in relation to the blood vessels were assessed by semiautomatic quantitative analysis.
MCT1 staining was present in hypoxic (pimonidazole stained) as well as non-hypoxic areas in almost equal amounts. MCT1 expression showed a significant overall correlation (r = 0.75, p < 0.001) and strong spatial relationship with CAIX. LDH-5 showed the strongest correlation with pimonidazole (r = 0.66, p = 0.002). MCT4 and GLUT-1 demonstrated a typical diffusion-limited hypoxic pattern and showed a high degree of colocalization. Both MCT4 and CAIX showed a higher expression in the primary tumor in node positive patients (p = 0.09 both).
Colocalization and staining patterns of metabolic and hypoxia-related proteins provides valuable additional information over single protein analyses and can improve the understanding of their functions and environmental influences.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
This study investigated the effectiveness of the Hanen More Than Words® (HMTW) program amongst parents of children with autism spectrum disorder (ASD) in Hong Kong. In this prospective cohort study, ...31 Cantonese-speaking young children with ASD and their parents were divided into either the HMTW group (
n
= 26) or a control group (
n
= 5). The HMTW intervention was provided over 11 weeks. The children’s communication abilities were measured prior to the intervention (Time 1) and 1 month after the end of the intervention (Time 2), and the results were compared between the two groups. The parents’ attributes and demographic information were measured at Time 1. The results showed a significant increase in children’s communication and social skills in the HMTW group compared with the control group. Children of parents with lower levels of Time 1 parenting self-efficacy exhibited facilitated growth in communication and social skills. These findings provide evidence of the effectiveness of the HMTW program in a Chinese cultural setting and demonstrate an important link between parenting self-efficacy and the effectiveness of the HMTW program.
Dynamic contrast-enhanced MRI (DCE-MRI) is a promising technique for assessing the response of tumor vasculature to antivascular therapies. Multiagent DCE-MRI employs a combination of low and high ...molecular weight contrast agents, which potentially improves the accuracy of estimation of tumor hemodynamic and vascular permeability parameters. In this study, we used multiagent DCE-MRI to assess changes in tumor hemodynamics and vascular permeability after vascular-disrupting therapy. Multiagent DCE-MRI (sequential injection of G5 dendrimer, G2 dendrimer, and Gd-DOTA) was performed in tumor-bearing mice before, 2 and 24 hours after treatment with vascular disrupting agent DMXAA or placebo. Constrained DCE-MRI gamma capillary transit time modeling was used to estimate flow F, blood volume fraction
, mean capillary transit time
, bolus arrival time
, extracellular extravascular fraction
, vascular heterogeneity index α
(all identical between agents) and extraction fraction E (reflective of permeability), and transfer constant
(both agent-specific) in perfused pixels. F,
, and α
decreased at both time points after DMXAA, whereas t
increased. E (G2 and G5) showed an initial increase, after which, both parameters restored.
(G2 and Gd-DOTA) decreased at both time points after treatment. In the control, placebo-treated animals, only F,
, and
Gd-DOTA showed significant changes. Histologic perfused tumor fraction was significantly lower in DMXAA-treated versus control animals. Our results show how multiagent tracer-kinetic modeling can accurately determine the effects of vascular-disrupting therapy by separating simultaneous changes in tumor hemodynamics and vascular permeability.
These findings describe a new approach to measure separately the effects of antivascular therapy on tumor hemodynamics and vascular permeability, which could help more rapidly and accurately assess the efficacy of experimental therapy of this class.
.
Abstract Background Hypoxia leads to changes in tumor cell metabolism such as increased glycolysis. In this study, we examined the spatial distribution of the glycolysis and hypoxia related markers ...glucose transporter 1 (GLUT1) and monocarboxylate transporter 4 (MCT4) expression in relation to the vasculature in stage I, II and resectable stage IIIA NSCLC. Furthermore, associations of these markers with survival were investigated. Methods GLUT1 and MCT4 expression were determined in 90 NSCLC fresh frozen biopsies using immunohistochemical techniques and a computerized image analysis system. Markers were analyzed for adenocarcinomas ( n = 41) and squamous cell carcinomas ( n = 34) separately. Eighty-four patients were retrospectively evaluated for relapse and survival. Results Squamous cell carcinomas demonstrated higher GLUT1 expression, relative to adenocarcinomas. Also, in squamous cell carcinomas, GLUT1 and MCT4 expression increased with increasing distance from the vasculature, whereas in adenocarcinomas upregulation of MCT4 was already found at closer distance from vessels. In adenocarcinomas, high GLUT1 expression correlated with a poor differentiation grade and positive lymph nodes at diagnosis. High GLUT1 plus high MCT4 expression was associated with a poor disease-specific survival in only adenocarcinomas ( p = 0.032). Conclusion Analysis of GLUT1 and MCT4 expression on the histological level suggested a different metabolism for adenocarcinomas and squamous cell carcinomas. Likely, adenocarcinomas rely mainly on aerobic glycolysis for ATP production, whereas the behavior of squamous cell carcinomas is more physiologically, i.e. mitochondrial oxidation with anaerobic glycolysis under hypoxic conditions. High GLUT1 plus high MCT4 expression indicated an aggressive tumor behavior in adenocarcinomas. This subgroup of tumors may benefit from new treatment approaches, such as MCT4 inhibitors. Since this study has an exploratory character, our results warrant further investigation and need independent validation.
Background
Both hypoxia and oncogenic mutations rewire tumor metabolism. In this study, glucose and glutamine metabolism‐related markers were examined in stage I ‐ resectable stage IIIA non‐small ...cell lung cancer (NSCLC). Furthermore, expression of metabolism‐related markers was correlated with mutational status to examine mutations associated with rewired tumor metabolism.
Methods
Mutation analysis was performed for 97 tumors. Glucose and glutamine metabolism‐related marker expression was measured by immunofluorescent staining (protein) and qPCR (mRNA) (n = 81).
Results
Glutamine metabolism‐related markers were significantly higher in adeno‐ than squamous cell NSCLCs. Glucose transporter 1 (GLUT1) protein expression was higher in solid compared to lepidic adenocarcinomas (P < 0.01). In adenocarcinomas, mRNA expression of glutamine transporter SLC1A5 correlated with tumor size (r(p) = 0.41, P = 0.005). Furthermore, SLC1A5 protein expression was significantly higher in adenocarcinomas with worse pTNM stage (r(s) = 0.39, P = 0.009). EGFR‐mutated tumors showed lower GLUT1 protein (P = 0.017), higher glutaminase 2 (GLS2) protein (P = 0.025) and higher GLS2 mRNA expression (P = 0.004), compared to EGFR wild‐type tumors. GLS mRNA expression was higher in KRAS‐mutated tumors (P = 0.019). TP53‐mutated tumors showed higher GLUT1 expression (P = 0.009).
Conclusions
NSCLC is a heterogeneous disease, with differences in mutational status and metabolism‐related marker expression between adeno‐ and squamous cell NSCLCs, and also within adenocarcinoma subtypes. GLUT1 and SLC1A5 expression correlate with aggressive tumor behavior in adenocarcinomas but not in squamous cell NSCLCs. Therefore, these markers could steer treatment modification for subgroups of adenocarcinoma patients. TP53, EGFR and KRAS mutations are associated with expression of glucose and glutamine metabolism‐related markers in NSCLC.
Carbonic anhydrase IX (CAIX) plays a pivotal role in pH homeostasis, which is essential for tumor cell survival. We examined the effect of the CAIX inhibitor 4-(3'(3",5"-dimethylphenyl)-ureido)phenyl ...sulfamate (S4) on the tumor microenvironment in a laryngeal tumor model by analyzing proliferation, apoptosis, necrosis, hypoxia, metabolism and CAIX ectodomain shedding.
SCCNij202 tumor bearing-mice were treated with S4 for 1, 3 or 5 days. CAIX ectodomain shedding was measured in the serum after therapy. Effects on tumor cell proliferation, apoptosis, necrosis, hypoxia (pimonidazole) and CAIX were investigated with quantitative immunohistochemistry. Metabolic transporters and enzymes were quantified with qPCR.
CAIX ectodomain shedding decreased after treatment with S4 (p<0.01). S4 therapy did neither influence tumor cell proliferation nor the amount of apoptosis and necrosis. Hypoxia (pimonidazole) and CAIX expression were also not affected by S4. CHOP and MMP9 mRNA as a reference of intracellular pH did not change upon treatment with S4. Compensatory mechanisms of pH homeostasis at the mRNA level were not observed.
As the clinical and biological meaning of the decrease in CAIX ectodomain shedding after S4 therapy is not clear, studies are required to elucidate whether the CAIX ectodomain has a paracrine or autocrine signaling function in cancer biology. S4 did not influence the amount of proliferation, apoptosis, necrosis and hypoxia. Therefore, it is unlikely that S4 can be used as single agent to influence tumor cell kill and proliferation, and to target primary tumor growth.
Celotno besedilo
Dostopno za:
DOBA, IZUM, KILJ, NUK, PILJ, PNG, SAZU, SIK, UILJ, UKNU, UL, UM, UPUK
Tumor hypoxia is an important cause of radioresistance and is associated with poor outcome.
SPECT (Single-photon emission computed tomography) imaging enables visualizing tumor characteristics. We ...investigated the SPECT-radiotracer 111In-girentuximab-F(ab’)2 to image Carbonic Anhydrase IX (CAIX), an enzyme upregulated under hypoxic conditions.
Athymic mice with subcutaneous FaDu or SCCNij202 head and neck squamous cell carcinoma (HNSCC) xenografts were treated with atovaquone or were housed in a hypoxic chamber (8% O2). Next, 111In-girentuximab-F(ab’)2 was injected and 24 h later mice were euthanized for ex vivo biodistribution, autoradiography of the tumor, and immunohistochemical staining of the tumor. Tumor sections were analyzed for hypoxia, CAIX expression, vessels, and perfusion. Also, the effect of atovaquone on microSPECT scans was determined in the FaDu model.
Atovaquone decreased CAIX expression by 69% (p = 0.017) compared with control tumors in FaDu, while in the SCCNij202 tumors no difference was observed. Hypoxic breathing did not increase CAIX expression or hypoxia staining in either tumor model, but did affect the necrotic tumor fraction. Ex vivo tracer uptake in the atovaquone treated group did not differ significantly from the control group, despite the difference in CAIX expression. Furthermore, SPECT imaging with 111In-girentuximab-F(ab’)2 did not discriminate atovaquone-treated versus control tumors.
Atovaquone decreased CAIX expression only in the FaDu tumor model. 111In-girentuximab-F(ab’)2 specifically targets CAIX-expressing areas in HNSCC xenografts, but differences in vessel density and necrosis most likely affected tracer uptake in the tumors and therefore complicated quantification of changes in CAIX expression.
Overexpression of epidermal growth factor receptor (EGFR) and tumor hypoxia have been shown to correlate with worse outcome in several types of cancer including head-and-neck squamous cell carcinoma. ...Little is known about the combination and possible interactions between the two phenomena.
In this study, 45 cases of histologically confirmed squamous cell carcinomas of the head and neck were analyzed. All patients received intravenous infusions of the exogenous hypoxia marker pimonidazole prior to biopsy. Presence of EGFR, pimonidazole binding, and colocalization between EGFR and tumor hypoxia were examined using immunohistochemistry.
Of all biopsies examined, respectively, 91% and 60% demonstrated EGFR- and pimonidazole-positive areas. A weak but significant association was found between the hypoxic fractions of pimonidazole (HFpimo) and EGFR fractions (F-EGFR) and between F-EGFR and relative vascular area. Various degrees of colocalization between hypoxia and EGFR were found, increasing with distance from the vasculature. A high fraction of EGFR was correlated with better disease-free and metastasis-free survival, whereas a high degree of colocalization correlated with poor outcome.
Colocalization of hypoxia and EGFR was demonstrated in head-and-neck squamous cell carcinomas, predominantly at longer distances from vessels. A large amount of colocalization was associated with poor outcome, which points to a survival advantage of hypoxic cells that are also able to express EGFR. This subpopulation of tumor cells might be indicative of tumor aggressiveness and be partly responsible for treatment resistance.
Purpose
Tumour cell hypoxia is a common feature in solid tumours adversely affecting radiosensitivity and chemosensitivity in head and neck squamous cell carcinomas. Positron emission tomography ...(PET) using the tracer
18
Ffluoromisonidazole (
18
FFMISO) is most frequently used for non-invasive evaluation of hypoxia in human tumours. A series of ten human head and neck xenograft tumour lines was used to validate
18
FFMISO as hypoxia marker at the microregional level.
Methods
Autoradiography after injection of
18
FFMISO was compared with immunohistochemical staining for the hypoxic cell marker pimonidazole in the same tumour sections of ten different human head and neck xenograft tumour lines. The methods were compared: first, qualitatively considering the microarchitecture; second, by obtaining a pixel-by-pixel correlation of both markers at the microregional level; third, by measuring the signal intensity of both images; and fourth, by calculating the hypoxic fractions by pimonidazole labelling.
Results
The pattern of
18
FFMISO signal was dependent on the distribution of hypoxia at the microregional level. The comparison of
18
FFMISO autoradiography and pimonidazole immunohistochemistry by pixel-by-pixel analysis revealed moderate correlations. In five tumour lines, a significant correlation between the mean
18
FFMISO and pimonidazole signal intensity was found (range,
r
2
= 0.91 to
r
2
= 0.99). Comparison of the tumour lines with respect to the microregional distribution pattern of hypoxia revealed that the correlation between the mean signal intensities strongly depended on the microarchitecture. Overall, a weak but significant correlation between hypoxic fractions based on pimonidazole labeling and the mean
18
FFMISO signal intensity was observed (
r
2
= 0.18,
p
= 0.02). For the three tumour models with a ribbon-like microregional distribution pattern of hypoxia, the correlation between the hypoxic fraction and the mean
18
FFMISO signal intensity was much stronger and more significant (
r
2
= 0.73,
p
< 0.001) than for the tumours with a more homogenous, patchy, microregional distribution pattern of hypoxia.
Conclusion
Different patterns of
18
FFMISO accumulation dependent on the underlying microregional distribution of hypoxia were found in ten head and neck xenograft tumours. A weak albeit significant correlation was found between the mean
18
FFMISO signal intensity and the hypoxic fraction of the tumours. In larger clinical tumours,
18
FFMISO–PET provides information on the tumour oxygenation status on a global level, facilitating dose painting in radiation treatment planning. However, caution must be taken when studying small tumour subvolumes as accumulation of the tracer depends on the presence of hypoxia and on the tumour microarchitecture.
Abstract Background Overexpression of EGFR correlates with decreased survival after radiotherapy in head and neck squamous cell carcinoma (HNSCC). However, the contribution of the activated form, ...pEGFR, and its downstream signaling (PI3-K/AKT) pathway is not clear yet. Methods Fifty-eight patients with HNSCC were included in the study. pEGFR, pAKT, hypoxia, and vessels were visualized using immunohistochemistry. Fractions (defined as the tumor area positive for the respective markers relative to the total tumor area) were calculated by automated image analysis and related to clinical outcome. Results Both pEGFR (median 0.6%, range 0–34%) and pAKT (median 1.8%, range 0–16%) expression differed between tumors. Also, a large variation in hypoxia was found (median pimonidazole fraction 3.9% 0–20%). A significant correlation between pEGFR and pAKT ( rs 0.44, p = 0.004) was seen, however, analysis revealed that this was not always based on spatial coexpression. Low pAKT expression was associated with increased risk of regional recurrence ( p < 0.05, log-rank) and distant metastasis ( p = 0.04). Conclusion The correlation between expression of pEGFR and pAKT is indicative of activation of the PI3-K/AKT pathway through phosphorylation of EGFR. Since not all tumors show coexpression to the same extent, other factors must be involved in the activation of this pathway as well.
PDF
![Correlation of [18F]FMISO a...](http://api.summon.serialssolutions.com/2.0.0/image/issn/XR4PS5YY4K/1619-7070_0340-6997/small "Correlation of [18F]FMISO autoradiography and pimonodazole immunohistochemistry in human head and neck carcinoma xenografts")
