Abstract Src family kinases (SFKs) have been implicated in resistance to both radiation and epidermal growth factor receptor (EGFR) inhibition. Therefore, we investigated whether inhibition of SFK ...through dasatinib (DSB) can enhance the effect of radiotherapy in two in vivo human head and neck squamous cell carcinoma (HNSCC) models. Response to DSB and/or radiotherapy was assessed with tumor growth delay assays in two HNSCC xenograft models, SCCNij153 and SCCNij202. Effects on EGFR signaling were evaluated withWestern blot analysis, and effects on DNA repair, hypoxia, and proliferation were investigated with immunohistochemistry. DSB and radiotherapy induced a significant growth delay in both HNSCC xenograft models, although to a lesser extent in SCCNij202. DSB did not inhibit phosphorylated protein kinase B (pAKT) or phosphorylated extracellular signal-regulated kinase 1/2 (pERK1/2) but did inhibit (phosphorylated) DNA-dependent protein kinase. Moreover, DSB reduced repair of radiation-induced DNA double-strand breaks as shown by an increase of p53-binding protein 1 (53BP1) staining 24 hours after radiation. This effect on DNA repair was only observed in the cell compartment where phosphorylated SFK (pSFK) was expressed: for SCCNij153 tumors in both normoxic and hypoxic areas and for SCCNij202 tumors only in hypoxic areas. No consistent effects of DSB on hypoxia or proliferation were observed. In conclusion, DSB enhances the effect of radiotherapy in vivo by inhibition of radiation-induced DNA repair and is a promising way to improve outcome in HNSCC patients.
Hypoxia is detected in most solid tumors and is associated with malignant progression and adverse treatment outcomes. However, the oxygenation status of malignant salivary gland tumors has not been ...previously studied. The aim of this study was to investigate the potential clinical relevance of hypoxia in this tumor type.
Twelve patients scheduled for surgical resection of a salivary gland tumor were preoperatively injected with the hypoxia marker pimonidazole and the proliferation marker iododeoxyuridine. Tissue samples of the dissected tumor were immunohistochemically stained for blood vessels, pimonidazole, carbonic anhydrase-IX, glucose transporters-1 and -3 (Glut-1, Glut-3), hypoxia-inducible factor-1alpha, iododeoxyuridine, and epidermal growth factor receptor. The tissue sections were quantitatively assessed by computerized image analysis.
The tissue material from 8 patients was of sufficient quality for quantitative analysis. All tumors were negative for pimonidazole binding, as well as for carbonic anhydrase-IX, Glut-1, Glut-3, and hypoxia-inducible factor-1alpha. The vascular density was high, with a median value of 285 mm(-2) (range, 209-546). The iododeoxyuridine-labeling index varied from <0.1% to 12.2% (median, 2.2%). Epidermal growth factor receptor expression levels were mostly moderate to high. In one-half of the cases, nuclear expression of epidermal growth factor receptor was observed.
The absence of detectable pimonidazole binding, as well as the lack of expression of hypoxia-associated proteins in all tumors, indicates that malignant salivary gland tumors are generally well oxygenated. It is unlikely that hypoxia is a relevant factor for their clinical behavior and treatment responsiveness.
Phenotype and Penetrance of the Dutch SDHB Mutation Carriers Rijken, Johannes A.; Niemeijer, Nienke D.; van der Horst-Schrivers, Anouk N.A. ...
Journal of Neurological Surgery Part B: Skull Base,
09/2016, Letnik:
77, Številka:
S 02
Conference Proceeding, Journal Article
Recenzirano
Odprti dostop
Objectives:
Nationwide evaluation of the phenotype and penetrance of SDHB mutation carriers.
Methods:
Mutations in SDHB predispose to skull base paragangliomas. In a nationwide study, all consecutive ...SDHB mutation carriers identified in the clinical genetics centers of the Netherlands were included in the analysis. Subjects were investigated according to structured protocols used for standard care in the Netherlands, including repetitive physical, biochemical and radiological screening for paraganglioma (PGL) and pheochromocytoma (PCC).
Results:
A total of 194 SDHB mutation carriers were included, carrying 27 different SDHB mutations. The most prevalent SDHB mutations are Dutch founder mutations: a deletion in exon 3 (31% of mutation carriers) and the c.423+1G>A mutation (24% of mutation carriers). In all, 93 tumors (PGL and PCC) were identified in 80 patients. 55 patients (28%) had a head and neck PGL, in total 63 tumors. 4 patients had a PCC (2%), 22 patients (11%) an extra-adrenal PGL (total 26 tumors) and 12 patients (6%) a malignant PGL. 114 SDHB mutation carriers displayed no physical, radiological or biochemical evidence of PGL or PCC.
Conclusion
: In the Netherlands, SDHB mutations are an infrequent finding. Carriers of SDHB mutations have a considerable risk of developing a PGL. Contrary to most previous reports, the most prevalent PGL location is in the head and neck region, abdominal and thoracic tumors are uncommon and malignancy is rare.
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.
Hypoxic cell turnover in different solid tumor lines Ljungkvist, Anna S E; Bussink, Johan; Kaanders, Johannes H A M ...
International journal of radiation oncology, biology, physics,
07/2005, Letnik:
62, Številka:
4
Journal Article
Recenzirano
Most solid tumors contain hypoxic cells, and the amount of tumor hypoxia has been shown to have a negative impact on the outcome of radiotherapy. The efficacy of combined modality treatments depends ...both on the sequence and timing of the treatments. Hypoxic cell turnover in tumors may be important for optimal scheduling of combined modality treatments, especially when hypoxic cell targeting is involved.
Previously we have shown that a double bioreductive hypoxic marker assay could be used to detect changes of tumor hypoxia in relation to the tumor vasculature after carbogen and hydralazine treatments. This assay was used in the current study to establish the turnover rate of hypoxic cells in three different tumor models. The first hypoxic marker, pimonidazole, was administered at variable times before tumor harvest, and the second hypoxic marker, CCI-103F, was injected at a fixed time before harvest. Hypoxic cell turnover was defined as loss of pimonidazole (first marker) relative to CCI-103F (second marker).
The half-life of hypoxic cell turnover was 17 h in the murine C38 colon carcinoma line, 23 h and 49 h in the human xenograft lines MEC82 and SCCNij3, respectively. Within 24 h, loss of pimonidazole-stained areas in C38 and MEC82 occurred concurrent with the appearance of pimonidazole positive cell debris in necrotic regions. In C38 and MEC82, most of the hypoxic cells had disappeared after 48 h, whereas in SCCNij3, viable cells that had been labeled with pimonidazole were still observed after 5 days.
The present study demonstrates that the double hypoxia marker assay can be used to study changes in both the proportion of hypoxic tumor cells and their lifespan at the same time. The present study shows that large differences in hypoxic cell turnover rates may exist among tumor lines, with half-lives ranging from 17-49 h.
In head and neck cancer, it has been shown that hypoxic tumors respond poorly to therapy. Methods to identify hypoxic tumors are, therefore, of importance to select patients for oxygenation modifying ...or other intensified treatments. The aim of this study was to compare tumor cell hypoxia assessed by the hypoxic cell marker pimonidazole (PIMO) with expression of the endogenous hypoxia-related marker carbonic anhydrase IX (CAIX) in three human head and neck tumor lines.
Forty-five tumors of three human head and neck tumor lines, SCCNij3, SCCNij59 and MEC82, xenografted in athymic mice, were used. CAIX was quantified by biodistribution (% injected dose/g tumor) after injecting 3–5
μl
111In-labeled G250 mouse antibody 3 days prior to euthanizing. In a tissue section from the same tumor, fractions of tumor area positive for PIMO, CAIX and Hoechst 33342 (perfusion marker) were assessed after immunohistochemical staining, using a digital image analysis system.
SCCNij3 and MEC82 were relatively hypoxic tumor lines with fractions of tumor area positive for pimonidazole of 0.16 and 0.15, respectively. SCCNij59 was a better-oxygenated tumor line with a PIMO-fraction of 0.03. The three tumor lines showed different levels and patterns of CAIX immunohistochemical staining, but only in MEC82 there was a good correlation between PIMO-fraction and CAIX-fraction (
r
2=0.92,
P<0.0001). Correlations between
111In-G250 uptake and CAIX-fraction or PIMO-fraction within tumor lines were weak or absent.
Assessment of CAIX expression depends largely on the techniques and tumor lines used. Furthermore, the immunohistochemical staining pattern of CAIX relative to PIMO differs between human tumor lines of similar anatomical origin. Therefore, the use of CAIX as endogenous marker of tumor hypoxia remains questionable.
To investigate hypoxia measured by pimonidazole binding, glucose transporter 1 (GLUT1) and carbonic anhydrase IX (CA-IX) expression, proliferation, and vascularity in liver metastases of colorectal ...cancer and to compare GLUT1 and CA-IX expression in corresponding primary tumors.
Twenty-five patients with liver metastases of colorectal cancer, planned for metastasectomy, were included. The hypoxia marker pimonidazole and proliferation marker iododeoxyuridine were administered before surgery. After immunofluorescent staining of the frozen metastases, pimonidazole binding, vascularity, and proliferation were analyzed quantitatively. Thirteen paraffin-embedded primary tumors were stained immunohistochemically for GLUT1 and CA-IX expression, which was analyzed semiquantitatively in primary tumors and corresponding liver metastases.
In liver metastases, pimonidazole binding showed a pattern consistent with diffusion-limited hypoxia. The mean pimonidazole-positive fraction was 0.146; the mean distance from vessels to pimonidazole-positive areas was 80 microm. When expressed, often co-localization was observed between pimonidazole binding and GLUT1 or CA-IX expression, but microregional areas of mismatch were also observed. No correlation between the level of pimonidazole binding and GLUT1 or CA-IX expression was observed. In some patients, a large fraction (up to 30%) of proliferating cells was present in pimonidazole-stained areas. Expression of CA-IX in primary tumors and metastases showed a significant correlation, which was absent for GLUT1 expression.
Compared with other tumor types, liver metastases of colorectal cancer contain large amounts of hypoxic cells. The lack of correlation with pimonidazole binding brings into question the value of GLUT1 and CA-IX as endogenous markers of hypoxia.
Infections of the neck are frequently seen in young children and are usually harmless and transient. In the case of atypical symptoms, however, it is important to be alert to the possibility of less ...common causes requiring specific treatment.
A 4-year-old girl was seen in the outpatient clinic with a recurrent, inflamed swelling in the neck. The swelling persisted despite repeated incision and drainage. Further investigation with MRI revealed a primary branchial cleft fistula, Work type 2. The epithelialized cartilaginous fistula tract ran from the external auditory canal to the neck, very close to the facial nerve, but could be surgically removed without damage to the nerve.
In a child with a recurrent swelling or abscess in the neck, with or without a fistula, an extensive differential diagnosis is required including branchial cleft fistula.
To evaluate erythropoietin receptor (EPOR) expression in human head and neck squamous cell carcinomas and correlate this to the presence of tumor hypoxia and treatment outcome.
Eighty-five patients ...with locally advanced tumors of the head and neck were included. Of these, 34 were given the hypoxia marker pimonidazole i.v. 2
h prior to biopsy taking. Contiguous paraffin embedded biopsies were stained for EPOR expression and, if administered, for pimonidazole binding. Immunohistochemical staining for EPOR was interpreted semiquantitatively according to a composite scale, ranging from 0 to 200. Pimonidazole positivity was quantitatively analyzed in a semiautomatic way.
Diffuse weak-to-moderate cytoplasmic and membrane EPOR immunostaining was observed in 80 of 85 biopsies (94%) and staining scores ranged from 0 to 198 (median 100). No correlations were found between EPOR expression, and the primary tumor site, T-stage or N-stage. Also, There was no association between EPOR expression and treatment outcome. The degree of tumor hypoxia represented by the relative area of pimonidazole binding varied between 0 and 26% (median 7%). Contiguous biopsy sections showed a lack of colocalization between EPOR and pimonidazole binding.
EPOR expression was demonstrated in the majority of the head and neck tumors. No colocalization was found between EPOR expression and pimonidazole binding indicating that the presence or absence of hypoxia did not necessarily indicate a distinct pattern of EPOR expression. The level of EPOR expression was not of prognostic significance in patients with head and neck cancer, although small effects of EPOR cannot be excluded because of the sample size of this study.
The worldwide incidence of abnormally invasive placenta is rapidly rising, following the trend of increasing cesarean delivery. It is a heterogeneous condition and has a high maternal morbidity and ...mortality rate, presenting specific intrapartum challenges. Its rarity makes developing individual expertise difficult for the majority of clinicians. The International Society for Abnormally Invasive Placenta aims to improve clinicians’ understanding and skills in managing this difficult condition. By pooling knowledge, experience, and expertise gained within a variety of different healthcare systems, the Society seeks to improve the outcomes for women with abnormally invasive placenta globally.
The recommendations presented herewith were reached using a modified Delphi technique and are based on the best available evidence. The evidence base for each is presented using a formal grading system. The topics chosen address the most pertinent questions regarding intrapartum management of abnormally invasive placenta with respect to clinically relevant outcomes, including the following: definition of a center of excellence; requirement for antenatal hospitalization; antenatal optimization of hemoglobin; gestational age for delivery; antenatal corticosteroid administration; use of preoperative cystoscopy, ureteric stents, and prophylactic pelvic arterial balloon catheters; maternal position for surgery; type of skin incision; position of the uterine incision; use of interoperative ultrasound; prophylactic administration of oxytocin; optimal method for intraoperative diagnosis; use of expectant management; adjuvant therapies for expectant management; use of local surgical resection; type of hysterectomy; use of delayed hysterectomy; intraoperative measures to treat life-threatening hemorrhage; and fertility after conservative management.
PDF
