Non-angiogenic tumours and their influence on cancer biology

Solid tumours need a blood supply, and a large body of evidence has previously suggested that they can grow only if they induce the development of new blood vessels, a process known as tumour angiogenesis. On the basis of this hypothesis, it was proposed that anti-angiogenic drugs should be able to suppress the growth of all solid tumours. However, clinical experience with anti-angiogenic agents has shown that this is not always the case. Reports of tumours growing without the formation of new vessels can be found in the literature dating back to the 1800s, yet no formal recognition, description and demonstration of their special biological status was made until recently. In 1996, we formally recognized and described non-angiogenic tumours in lungs where the only blood vessels present were those originating from normal lung tissue. This is far from an isolated scenario, as non-angiogenic tumour growth has now been observed in tumours of many different organs in both humans and preclinical animal models. In this Opinion article, we summarize how these tumours were discovered and discuss what we know so far about their biology and the potential implications of this knowledge for cancer treatment.

Whole-genome sequencing identifies homozygous BRCA2 deletion guiding treatment in dedifferentiated prostate cancer

Whole-genome sequencing (WGS) has transformed the understanding of the genetic drivers of cancer and is increasingly being used in cancer medicine to identify personalized therapies. Here we describe a case in which the application of WGS identified a tumoral BRCA2 deletion in a patient with aggressive dedifferentiated prostate cancer that was repeat-biopsied after disease progression. This would not have been detected by standard BRCA testing, and it led to additional treatment with a maintenance poly ADP ribose polymerase (PARP) inhibitor following platinum-based chemotherapy. This case demonstrates that repeat biopsy upon disease progression and application of WGS to tumor samples has meaningful clinical utility and the potential to transform outcomes in patients with cancer.

Hypoxia-related biological markers as predictors of epirubicin-based treatment responsiveness and resistance in locally advanced breast cancer

PURPOSE

To identify hypoxia-related biomarkers indicative of response and resistance to epirubicin treatment in patients with locally advanced breast cancer.

PATIENTS AND METHODS

One hundred seventy-six women with T2-4 N0-1 breast tumours were randomly assigned to receive epirubicin 120 mg/m2/1-21 (EPI ARM), epirubicin 120 mg/m2/1-21 + erythropoietin 10.000 IU sc three times weekly (EPI-EPO ARM) and epirubicin 40 mg/m2/w-q21 (EPI-W ARM). Sixteen tumour proteins involved in cell survival, hypoxia, angiogenesis and growth factor, were assessed by immunohistochemistry in pre-treatment samples. A multivariate generalized linear regression approach was applied using a penalized least-square minimization to perform variable selection and regularization.

RESULTS

VEGF and GLUT-1 expression were significantly positively associated with complete response (CR) to treatment in all leave-one-out iterations. Bcl-2 expression was inversely correlated with pCR, whilst EPO expression was positively correlated with pathological complete response (pCR). Haemaglobin and HIF-1a nuclear expression were inversely correlated with pCR. HB and HIF-1a expression were associated with a higher risk of relapse and overall survival.

CONCLUSION

Hypoxic biomarkers determines the epirubicin resistance in breast cancer. Assessment of such biomarkers, may be useful for predicting chemosensitivity and also anthracycline-based treatment outcome.

Twenty years after: the beautiful hypothesis and the ugly facts

The limited clinical benefits from current antiangiogenic therapy for cancer patients have triggered some critical thoughts and insightful investigations aiming to further elucidate the relationship between vessels and cancer. Tumors need blood perfusion but there are mounting evidences that angiogenesis alone does not explain it in all the neoplasms. In this editorial, for a special issue on tumor and vessels published in the Chinese Journal of Cancer, we briefly introduce the history of the evidences that solid tumors can sometimes obtain blood perfusion by alternative approaches other than sprouting angiogenesis, i.e., vessel co-option and vasculogenic mimicry. This editorial provides also the links to several most recently published discoveries and hypotheses on tumor interaction with blood vessels.

Biological and Prognostic Significance of the Morphological Types and Vascular Patterns in Colorectal Liver Metastases (CRLM): Looking Beyond the Tumor Margin

Patients with encapsulated colorectal liver metastases (CRLM) have a better prognosis than those without a capsule. The reason for the encapsulation is unknown. Hypoxia inducible factor-1α (HIF-1α) increases tumor angiogenesis and tumor tissue expression is associated with reduced survival. Our aim was to determine whether the good prognosis of encapsulated CRLM is associated with reduced HIF-1α expression by the cancer.The study selected only patients who had not undergone neoadjuvant chemotherapy prior to a potentially curative hepatectomy for CRLM. From 30 selected patients, serial sections were cut from a single randomly selected metastasis. Morphology was assessed following H&E staining. Tumor hypoxia, vascular endothelial growth factor (VEGF), proliferation, and microvascular density (MVD) were assessed by immunostaining for HIF-1α and carbonic anhydrase-9 (CA-9), VEGF, Ki67, and cluster of differentiation-31, respectively. MVD was calculated in the vascular hot spots. Pathology was reported without clinical outcome information. Actual long-term survival was recorded.Thirteen (43%) of the cancers were encapsulated CRLM containing glands which were large, complex, and cribriform. Thirteen (43%) were infiltrative CRLM and their glands were small, closely packed, and rounded with vessels in the interglandular fibrous tissue with no capsule; 3 (10%) had a mixed picture. Encapsulated CRLM had a higher expression of HIF-1α (58% vs 8%, P = 0.03), CA-9 (42% vs 0%, P = 0.04), and VEGF (92% vs 25%, P = 0.02). MVD was lower in the encapsulated CRLM group (37 mm vs 143 mm, P < 0.001). The median follow-up was 115 months. The encapsulated CRLM group had a better overall and 5-year survival (relative hazard: 0.58, P = 0.057 and hazard ratio: 0.52, P = 0.044).There are 2 main morphological appearances of CRLM which have very different long-term survival following liver resection surgery. The morphology is associated with differences in expression of HIF-1α, CA-9, VEGF, and angiogenesis.

Gene Signatures Stratify Computed Tomography Screening Detected Lung Cancer in High-Risk Populations

BACKGROUND

Although screening programmes of smokers have detected resectable early lung cancers more frequently than expected, their efficacy in reducing mortality remains debatable. To elucidate the biological features of computed tomography (CT) screening detected lung cancer, we examined the mRNA signatures on tumours according to the year of detection, stage and survival.

METHODS

Gene expression profiles were analysed on 28 patients (INT-IEO training cohort) and 24 patients of Multicentre Italian Lung Detection (MILD validation cohort). The gene signatures generated from the training set were validated on the MILD set and a public deposited DNA microarray data set (GSE11969). Expression of selected genes and proteins was validated by real-time RT-PCR and immunohistochemistry. Enriched core pathway and pathway networks were explored by GeneSpring GX10.

FINDINGS

A 239-gene signature was identified according to the year of tumour detection in the training INT-IEO set and correlated with the patients' outcomes. These signatures divided the MILD patients into two distinct survival groups independently of tumour stage, size, histopathological type and screening year. The signatures can also predict survival in the clinically detected cancers (GSE11969). Pathway analyses revealed tumours detected in later years enrichment of the PI3K/PTEN/AKT pathway, with up-regulation of PDPK1, ITGB1 and down-regulation of FOXO1A. Analysis of normal lung tissue from INT-IEO cohort produced signatures distinguishing patients with early from late detected tumours.

INTERPRETATION

The distinct pattern of "indolent" and "aggressive" tumour exists in CT-screening detected lung cancer according to the gene expression profiles. The early development of an aggressive phenotype may account for the lack of mortality reduction by screening observed in some cohorts.

Incidence, management, and outcome of high-grade transformation of nodular lymphocyte predominant Hodgkin lymphoma: long-term outcomes from a 30-year experience

Nodular lymphocyte predominant Hodgkin lymphoma (NLPHL) is a rare form of Hodgkin lymphoma that typically presents as early stage, indolent disease in young adult males. The relationship between NLPHL and DLBCL is incompletely understood, and there remains a paucity of data with regard the incidence and management of high-grade transformation. We report the largest study to date describing the incidence, management and long-term outcome of 26 cases of high-grade transformation of NLPHL over a 30-year period. We report a transformation incidence of 17.0%. Bone marrow, splenic, and liver infiltration with DLBCL was frequent. Patients with an aa-IPI 2-3 have poorer OS and PFS (P = 0.034 and P = 0.009, respectively). Although the approach to treatment was somewhat variable, typically young, otherwise fit patients received anthracycline-based induction, platinum-based consolidation with stem cell harvesting, followed by autologous SCT with BEAM conditioning. Long-term (5 year) PFS was over 60% with this approach, and comparable to our de novo DLBCL historical age and time period-matched cohort largely treated with CHOP-like chemotherapy alone. The transformation rate of 17.0% highlights the importance of accurate initial diagnosis, long-term follow-up, and re-biopsy at relapse.

Non-angiogenic tumours unveil a new chapter in cancer biology

The term 'angiogenesis' was coined in 1787 and the role of vessels in cancer has been studied ever since. In 1971 Folkman introduced the hypothesis, until now widely accepted, that tumour growth is strictly dependent on angiogenesis. However, the discovery that tumours can also grow without angiogenesis by exploiting pre-existing vessels, both in humans and more recently in mice, has demonstrated that this is not always the case. These observations highlight a new aspect of the interaction between vessels and tumours and demonstrate the existence of a previously unrecognized group of tumours that grow without angiogenesis and whose biology is, so far, largely unknown.

Combination of letrozole, metronomic cyclophosphamide and sorafenib is well-tolerated and shows activity in patients with primary breast cancer

PURPOSE

To assess whether the combination of letrozole, metronomic cyclophosphamide and sorafenib (LCS) is well tolerated and shows activity in primary breast cancer (BC).

METHODS

Thirteen oestrogen receptor-positive, postmenopausal, T2-4, N0-1 BC patients received the LCS combination for 6 months. In these patients we examined the pharmacokinetics of sorafenib and cyclophosphamide, toxicity of the regimen, the clinical response to therapy and changes in the levels of biologically relevant biomarkers.

RESULTS

Adequate plasma concentrations of sorafenib were achieved in patients when it was dosed in combination with L+C. The mean plasma concentrations of C were consistently lower following administration of LCS, compared with administration of L+C only. The most common drug-related grade 3/4 adverse events were skin rash (69.3%), hand-foot skin reaction (69.3%) and diarrhoea (46.1%). According to RECIST Criteria, a clinical complete response was observed in 6 of 13 patients. A significant reduction in tumour size, evaluated with MRI, was also observed between baseline and 14 days of treatment in all 13 patients (P=0.005). A significant reduction in SUV uptake, measured by (18)FDG-PET/CT, was observed in all patients between baseline and 30 days of treatment (P=0.015) and between baseline and definitive surgery (P=0.0002). Using modified CT Criteria, a response was demonstrated in 8 out of 10 evaluable patients at 30 days and in 11 out of 13 evaluable patients at the definitive surgery. A significant reduction in Ki67 expression was observed in all patients at day 14 compared with baseline (P<0.00001) and in 9 out of 13 patients at the definitive surgery compared with baseline (P<0.03). There was also a significant suppression of CD31 and VEGF-A expression in response to treatment (P=0.01 and P=0.007, respectively).

CONCLUSIONS

The LCS combination is feasible and tolerable. The tumour response and target biomarker modulation indicate that the combination is clinically and biologically active.

JMY protein, a regulator of P53 and cytoplasmic actin filaments, is expressed in normal and neoplastic tissues

JMY is a p300-binding protein with dual action: by enhancing P53 transcription in the nucleus, it plays an important role in the cellular response to DNA damage, while by promoting actin filament assembly in the cytoplasm; it induces cell motility in vitro. Therefore, it has been argued that, depending of the cellular setting, it might act either as tumor suppressor or as oncogene. In order to further determine its relevance to human cancer, we produced the monoclonal antibody HMY 117 against a synthetic peptide from the N-terminus region and characterized it on two JMY positive cell lines, MCF7 and HeLa, wild type and after transfection with siRNA to switch off JMY expression. JMY was expressed in normal tissues and heterogeneously in different tumor types, with close correlation between cytoplasmic and nuclear expression. Most noticeable was the loss of expression in some infiltrating carcinomas compared to normal tissue and in in situ carcinomas of the breast, which is consistent with a putative suppressor role. However, as in lymph node metastases, expression of JMY was higher than in primary colorectal and head and neck carcinomas, it might also have oncogenic properties depending on the cellular context by increasing motility and metastatic potential.

TRAP1 regulates proliferation, mitochondrial function, and has prognostic significance in NSCLC

The TNF receptor-associated protein 1 (TRAP1) is a mitochondrial HSP that has been related to drug resistance and protection from apoptosis in colorectal and prostate cancer. Here, the effect of TRAP1 ablation on cell proliferation, survival, apoptosis, and mitochondrial function was determined in non-small cell lung cancer (NSCLC). In addition, the prognostic value of TRAP1 was evaluated in patients with NSCLC. These results demonstrate that TRAP1 knockdown reduces cell growth and clonogenic cell survival. Moreover, TRAP1 downregulation impairs mitochondrial functions such as ATP production and mitochondrial membrane potential as measured by TMRM (tetramethylrhodamine methylester) uptake, but it does not affect mitochondrial density or mitochondrial morphology. The effect of TRAP1 silencing on apoptosis, analyzed by flow cytometry and immunoblot expression (cleaved PARP, caspase-9, and caspase-3) was cell line and context dependent. Finally, the prognostic potential of TRAP1 expression in NSCLC was ascertained via immunohistochemical analysis which revealed that high TRAP1 expression was associated with increased risk of disease recurrence (univariate analysis, P = 0.008; multivariate analysis, HR: 2.554; 95% confidence interval, 1.085-6.012; P = 0.03). In conclusion, these results demonstrate that TRAP1 impacts the viability of NSCLC cells, and that its expression is prognostic in NSCLC.

IMPLICATIONS

TRAP1 controls NSCLC proliferation, apoptosis, and mitochondrial function, and its status has prognostic potential in NSCLC.

Type II EATL (epitheliotropic intestinal T-cell lymphoma): a neoplasm of intra-epithelial T-cells with predominant CD8αα phenotype

In this multicentre study, we examined 60 cases of Type II enteropathy-associated T-cell lymphoma (EATL) from the Asia-Pacific region by histological review, immunohistochemistry and molecular techniques. Patients were mostly adult males (median age: 58 years, male:female 2.6:1), presenting with abdominal pain (60%), intestinal perforation (40%) and weight loss (28%). None had a history of coeliac disease and the median survival was only 7 months. Histologically, these tumours could be divided into (i) central tumour zone comprising a monotonous population of neoplastic lymphocytes, (ii) peripheral zone featuring stunted villi and morphologically atypical lymphocytes showing epitheliotropism, and (iii) distant mucosa with normal villous architecture and cytologically normal intra-epithelial lymphocytes (IELs). Characterized by extensive nuclear expression of Megakaryocyte-associated tyrosine kinase (MATK) (87%) and usually a CD8(+)CD56(+) (88%) cytotoxic phenotype, there was frequent aberrant expression of CD20 (24%). T-cell receptor (TCR) expression was silent or not evaluable in 40% but of the remainder, there was predominant expression of TCRαβ over TCRγδ (1.6:1). In keeping with the normal ratio of IEL subsets, CD8(+) cases showed predominant CD8αα homodimer expression (77%), regardless of TCR lineage. These tumours constitute a distinct entity from classical EATL, and the pathology may reflect tumour progression from IEL precursors, remnants of which are often seen in the distant mucosa.

Carbonic anhydrase IX promotes tumor growth and necrosis in vivo and inhibition enhances anti-VEGF therapy

PURPOSE

Bevacizumab, an anti-VEGFA antibody, inhibits the developing vasculature of tumors, but resistance is common. Antiangiogenic therapy induces hypoxia and we observed increased expression of hypoxia-regulated genes, including carbonic anhydrase IX (CAIX), in response to bevacizumab treatment in xenografts. CAIX expression correlates with poor prognosis in most tumor types and with worse outcome in bevacizumab-treated patients with metastatic colorectal cancer, malignant astrocytoma, and recurrent malignant glioma.

EXPERIMENTAL DESIGN

We knocked down CAIX expression by short hairpin RNA in a colon cancer (HT29) and a glioblastoma (U87) cell line which have high hypoxic induction of CAIX and overexpressed CAIX in HCT116 cells which has low CAIX. We investigated the effect on growth rate in three-dimensional (3D) culture and in vivo, and examined the effect of CAIX knockdown in combination with bevacizumab.

RESULTS

CAIX expression was associated with increased growth rate in spheroids and in vivo. Surprisingly, CAIX expression was associated with increased necrosis and apoptosis in vivo and in vitro. We found that acidity inhibits CAIX activity over the pH range found in tumors (pK = 6.84), and this may be the mechanism whereby excess acid self-limits the build-up of extracellular acid. Expression of another hypoxia inducible CA isoform, CAXII, was upregulated in 3D but not two-dimensional culture in response to CAIX knockdown. CAIX knockdown enhanced the effect of bevacizumab treatment, reducing tumor growth rate in vivo.

CONCLUSION

This work provides evidence that inhibition of the hypoxic adaptation to antiangiogenic therapy enhances bevacizumab treatment and highlights the value of developing small molecules or antibodies which inhibit CAIX for combination therapy.

Lymphoid proliferations of indeterminate malignant potential arising in adults with common variable immunodeficiency disorders: unusual case studies and immunohistological review in the light of possible causative events

Patients with common variable immunodeficiency disorders (CVIDs) who developed B cell lymphoproliferation of indeterminate malignant potential are described in order to raise a discussion of the relationship between infection and lymphoproliferation in infection prone patients. Those with CVID are at risk of developing either polyclonal or monoclonal lymphoproliferation in part due to the dysregulation of their adaptive immune systems. The aetiologies of the lymphoproliferations are unknown but intriguing; the relevance of infection being particularly problematic. The patients described here demonstrate variability in preceding infection, age at presentation, response to antibiotics and other types of therapy as well as outcome. The question of treatment is also controversial; issues include whether antibiotics or chemotherapy are the first line of therapy in all patients and whether transformation to aggressive B cell malignancy is inevitable or depends on other factors and if so, the length of time for such progression.

Effects of HIF-1alpha and HIF2alpha on Growth and Metabolism of Clear-Cell Renal Cell Carcinoma 786-0 Xenografts

In cultured clear-cell renal carcinoma (CCRCC) 786-0 cells transfected with HIF1alpha (HIF-1+), HIF-2alpha (HIF-2+), or empty vector (EV), no significant differences were observed in the growth rates in vitro, but when grown in vivo as xenografts HIF-2alpha significantly increased, and HIF-1alpha significantly decreased growth rates, compared to EV tumors. Factors associated with proliferation were increased and factors associated with cell death were decreased in HIF-2+ tumors. Metabolite profiles showed higher glucose and lower lactate and alanine levels in the HIF-2+ tumors whilst immunostaining demonstrated higher pyruvate dehydrogenase and lower pyruvate dehydrogenase kinase 1, compared to control tumors. Taken together, these results suggest that overexpression of HIF-2alpha in CCRCC 786-0 tumors regulated growth both by maintaining a low level of glycolysis and by allowing more mitochondrial metabolism and tolerance to ROS induced DNA damage. The growth profiles observed may be mediated by adaptive changes to a more oxidative phenotype.

Atrial fibrillation is associated with cardiac hypoxia

BACKGROUND

Atrial fibrillation (AF), the most common human arrhythmia, is responsible for substantial morbidity and mortality and may be promoted by selective atrial ischemia and atrial fibrosis. Consequently, we investigated markers for hypoxia and angiogenesis in AF.

METHODS

Right atrial appendages (n=158) were grouped according to heart rhythm [sinus rhythm (SR) or AF]. The degree of fibrosis and microvessel density of all patients were determined morphometrically using Sirius-Red- and CD34/CD105-stained sections, respectively. Next, sections (n=77) underwent immunostaining to detect hypoxia- and angiogenesis-related proteins [hypoxia-inducible factor (HIF)1 alpha, HIF2 alpha, vascular endothelial growth factor (VEGF), VEGF receptor 2 (KDR), phosphorylated KDR (pKDR), carboanhydrase IX, platelet-derived growth factor] and the apoptosis-related B-cell lymphoma 2 protein.

RESULTS

Fibrosis progressed significantly from 14.7+/-0.8% (SR) to 22.3+/-1.4% (AF). While the positive cytoplasmic staining of HIF1 alpha, HIF2 alpha, VEGF, KDR, and pKDR rose significantly from SR to AF, their nuclear fractions fell (only pKDR significantly). The median CD34/CD105-positive microvessel size increased significantly from SR to AF.

CONCLUSIONS

AF is closely associated with an atrial up-regulation of hypoxic and angiogenic markers. Whether this is cause, effect, or co-phenomenon of fibrosis remains to be investigated. It is conceivable that fibrosis might lead to an increased O(2) diffusion distance and thus induce ischemic signaling, which, in turn, leads to angiogenesis.

Overexpression of the oxygen sensors PHD-1, PHD-2, PHD-3, and FIH Is associated with tumor aggressiveness in pancreatic endocrine tumors

PURPOSE

Tumor hypoxia is associated with poor prognosis and resistance to treatment. Our aim was to assess the expression of proteins that act as cellular oxygen sensors, directly regulating the hypoxia inducible factor (HIF) pathway, i.e., prolyl hydroxylase domain proteins (PHD)-1, PHD-2, PHD-3, and FIH in pancreatic endocrine tumors (PET).

EXPERIMENTAL DESIGN

Immunohistochemical expression of these markers was examined in 109 PET included in tissue microarrays and representing various stages of tumorigenesis. The results were correlated with histoprognostic factors including Ki-67 index, presence of a fibrotic focus, and microvascular density (MVD).

RESULTS

The cytoplasmic and nuclear expressions of the three PHD isoforms were associated, and their expression was significantly higher in aggressive PETS, malignant, with lymph node metastases or with lower MVD. High nuclear expression of the three isoforms highly correlated with HIF-1alpha nuclear expression (P = 0.02, 0.003, and 0.006, respectively). Moreover, high nuclear PHD-1 or PHD-3 expression was associated with a poorer survival (P = 0.01). Cytoplasmic FIH was significantly higher in malignant PETs (P = 0.05) and in PETs with lymph node metastases (P = 0.02), and its expression correlated positively with those of cytoplasmic PHD isoforms (P < 0001). FIH stromal expression was found in 23% of PETs and correlated with higher FIH nuclear expression (P = 0.0004) and poorer disease-free survival (P = 0.0018).

CONCLUSION

HIF regulatory proteins are highly expressed in PET and their expression is correlated with tumor metastases, tumor recurrence, and prognosis. These molecules that play an important role in the control of hypoxia-induced genes may have a function in the regulation of cellular proliferation and differentiation during endocrine tumorigenesis.

Expression of hypoxia-related tissue factors in astrocytic gliomas. A multivariate survival study with emphasis upon carbonic anhydrase IX

Carbonic anhydrase IX (CAIX) is a transmembrane enzyme involved in the reversible metabolism of carbon dioxide to carbonic acid and, hence, in physiological pH regulation. It also participates in cellular differentiation and proliferation, its expression being absent in most normal tissues. It has been recently postulated that the hypoxia-inducible factor (HIF-1) pathway up-regulated by hypoxia accounts for CAIX overexpression in most human tumors. In the present study, we examined the expression of this enzyme in diffuse gliomas of astrocytic origin in relation to vascular endothelial growth factor (VEGF) and HIF-1alpha expression, proliferation rate (as assessed with Ki-67 antigen), microvessel morphology, and survival. Of 84 cases analyzed, 61 cases (72.6%) displayed strong membrane and/or cytoplasmic expression of CAIX and were grouped as positive. Immunoreactivity tended to have a perinecrotic distribution and increased in parallel with the extent of necrosis (P < .001) and histologic grade (P < .001). A positive correlation was also noted with HIF-1alpha and VEGF expression (P < .001), proliferation rate (P = .010), microvessel density (P = .004), and microvessel caliber parameters (P = .014-.038). In univariate survival analysis, increased CAIX expression was associated with shortened survival in the entire cohort (P < .0001), along with VEGF (P = .0205) and HIF-1alpha levels (P = .0190). Multivariate analysis selected the interaction model of CAIX, with grade and age as the only parameters independently affecting survival. CAIX expression was also the only significant parameter for the survival of patients with grades II/III. We conclude that CAIX may be used as a prognostic indicator in diffuse astrocytomas to refine the information provided by grade. Given the role of CAIX in the acidification of tumor environment and its up-regulation by hypoxia, it is thought that CAIX expression may be linked to resistance of tumor cells to radiotherapy by allowing them to acclimatize to a hypoxic and acidic microenvironment.

Identification of potential therapeutic targets by gene-expression profiling in pancreatic endocrine tumors

BACKGROUND & AIMS

Prediction of biological behavior in pancreatic endocrine tumors (PET) is difficult on histologic criteria alone. The aim of this study was to characterize PET gene expression by complementary DNA (cDNA) microarray and identify specific differences in gene-expression profiles between nonmetastatic and metastatic tumors.

METHODS

We studied 24 well-differentiated PETs corresponding to 12 benign tumors and to 12 carcinomas with metastasis. Total RNAs were extracted followed by microarray hybridization, imaging scan procedure, and statistical anaylsis. PET tissue arrays were constructed from 129 archival tumors for immunohistochemical validation of microarray data.

RESULTS

A total of 123 transcripts were found to separate nonmetastatic from metastatic PETs (ie, 72 up-regulated and 51 down-regulated genes in malignant tumors). Some of these genes were involved in pathways related to (1) angiogenesis and remodeling (CD34, cadherin-5, E-selectin, semaphorin E, and fibrillin), (2) signal transduction through tyrosine kinases (tyrosine kinase-2, platelet-derived growth factor-Rbeta, MKK4, and discoidin domain receptor-1), (3) calcium-dependent cell signaling (transient receptor potential cation channel-1, calcium channel voltage-dependent beta2, neurocalcin delta, and GABA-A receptor gamma2), and (4) response to drug (MDR1 and carcinoembryonic antigen-related cell adhesion molecule 6). By using tissue arrays, we confirmed the differential expression of CD34 (P = .0008), E-selectin (P = .003), MKK4 (P = .0001), and MDR1 (P = .0003) in metastatic vs nonmetastatic PETs.

CONCLUSIONS

This study provides insight into tumorigenic pathways in PET. Some of the genes identified are potentially new molecular markers for the detection and treatment of these tumors.

Is nonangiogenesis a novel pathway for cancer progression? A study using 3-dimensional tumour reconstructions

The nonangiogenic lung tumour is characterized by neoplastic cells co-opting the pre-existent vasculature and filling the alveoli space. 3-Dimensional reconstruction of the tumour reveals that this particular tumour progresses without neovascularization and there is no major destruction of the lung's architectural integrity.

Expression of hypoxia-inducible factors is correlated with the presence of a fibrotic focus and angiogenesis in pancreatic ductal adenocarcinomas

AIMS

To study the expression of hypoxia-regulated markers in pancreatic ductal adenocarcinomas (PA) in relationship to the presence of a fibrotic focus, angiogenesis quantification and clinical outcome.

METHODS AND RESULTS

The expression of hypoxia-inducible factor (HIF)-1alpha, HIF-2alpha, carbonic anhydrase 9 (CA9) and vascular endothelial growth factor (VEGF) was immunohistochemically detected in 50 PA and correlated with tumour characteristics, microvascular density (MVD) and survival. HIF-1alpha was expressed within tumour cells in 68%, HIF-2alpha in 46%, CA9 in 78% and VEGF in 52% of the cases. Stromal expression was also noted for HIF-2alpha and CA9 in, respectively, 42% and 48% of the cases. Tumour CA9 expression was associated with that of VEGF (P=0.004) and that of stromal HIF-2alpha (P=0.013), with the presence of a fibrotic focus (P=0.046) and with an increased MVD (P=0.034). Tumour VEGF expression correlated with the presence of a fibrotic focus (P=0.039) and a greater MVD (P=0.047). Both the presence of a fibrotic focus (P=0.0002) and high tumour CA9 expression (P=0.029) were associated with reduced overall survival.

CONCLUSION

The strong association of the presence of a fibrotic focus with CA9 expression and lower survival demonstrates that hypoxia-driven angiogenesis plays an important role in the progression of PA.

Expression and cellular localization of vascular endothelial growth factor A and its receptors in acute and chronic leukemias: An immunohistochemical study

We aimed to study the expression of phosphorylated vascular endothelial growth factor receptor 2 (pVEGFR-2), a membrane-bound tyrosine kinase receptor to vascular endothelial growth factor, in 76 cases of leukemia and nonneoplastic myeloproliferative disease and in 8 reactive bone marrows. The microvessel density (MVD) and the expression of both pVEGFR-2 and its ligand, VEGFA, were evaluated in these cases. We used archival cases and immunohistochemistry with a monoclonal antibody generated by us to the autophosphorylation sites in the cytoplasmic tail of VEGFR-2 and von Willebrand factor antibody to evaluate MVD. Our results demonstrate increased expression of this phosphorylated receptor in the neoplastic cells in acute myeloid and lymphoblastic leukemias. This correlated with increased MVD and VEGFA expression by the neoplastic cells. Interestingly, there was nuclear relocation of this receptor in these diseases. This raises the possibility that pVEGFR-2 may be involved in the transcriptional regulation of these leukemias. Small molecule inhibitors to this receptor may therefore be a useful adjunct in the therapy for these diseases.

Gene expression signature for angiogenic and nonangiogenic non-small-cell lung cancer

Angiogenesis is regarded as essential for tumour growth. However, we have demonstrated that some other aggressive non-small-cell lung carcinomas (n-SCLC) do not have angiogenesis. In this study, using cDNA microarray analysis, we demonstrate that angiogenic and nonangiogenic tumour types can be distinguished by their gene expression profiles. Tissue samples from 42 n-SCLC patients were obtained with consent. In all, 12 tumours were nonangiogenic and 30 angiogenic. The two groups were matched by age, sex, smoking and tumour stage. Total RNAs were extracted followed by microarray hybridization and image scan procedure. Data were analysed using GeneSpring 5.1 software. A total of 62 genes were found to be able to separate angiogenic from nonangiogenic tumours. Nonangiogenic tumours have higher levels of genes concerned with mitochondrial metabolism, mRNA transcription, protein synthesis and the cell cycle. Angiogenic tumours have higher levels of genes coding for membrane vesicles, integrins, remodelling, angiogenesis and apoptosis. These results further support our first finding that nonangiogenic lung tumours are fast-growing tumours filling the alveoli in the absence of vascular remodelling. We raise the hypothesis that in nonangiogenic tumours, hypoxia leads to a higher activation of the mitochondrial respiratory chain, which allows tumour growth without triggering angiogenesis.

Microvascular density and hypoxia-inducible factor pathway in pancreatic endocrine tumours: negative correlation of microvascular density and VEGF expression with tumour progression

Tumour-associated angiogenesis is partly regulated by the hypoxia-inducible factor (HIF) pathway. Endocrine tumours are highly vascularised and the molecular mechanisms of their angiogenesis are not fully delineated. The aim of this study is to evaluate angiogenesis and expression of HIF-related molecules in a series of patients with pancreatic endocrine tumours (PETs). The expression of vascular endothelial growth factor (VEGF), HIF-1alpha, HIF-2alpha and carbonic anhydrase 9 (CA9) was examined by immunohistochemistry in 45 patients with PETs and compared to microvascular density (MVD), endothelial proliferation, tumour stage and survival. Microvascular density was very high in PETs and associated with a low endothelial index of proliferation. Microvascular density was significantly higher in benign PETs than in PETs of uncertain prognosis, well-differentiated and poorly differentiated carcinomas (mean values: 535, 436, 252 and 45 vessels mm(-2), respectively, P < 0.0001). Well-differentiated tumours had high cytoplasmic VEGF and HIF-1alpha expression. Poorly differentiated carcinomas were associated with nuclear HIF-1alpha and membranous CA9 expression. Low MVD (P = 0.0001) and membranous CA9 expression (P = 0.0004) were associated with a poorer survival. Contrary to other types of cancer, PETs are highly vascularised, but poorly angiogenic tumours. As they progress, VEGF expression is lost and MVD significantly decreases. The regulation of HIF signalling appears to be specific in pancreatic endocrine tumours.

Late relapse of myelodysplasia after allogeneic transplantation concomitant with new presentation of invasive liposarcoma as a secondary neoplasm

Second malignancies are uncommon events in the survivors of allogeneic transplant procedures, although they are increased compared to normal control populations. Among these malignancies, sarcomas are exceedingly rare. In addition, relapse of primary myelodysplasia rarely occurs after 5 years from the time of allogeneic transplantation. This report describes an unusual presentation of liposarcoma with concomitant relapse of underlying myelodysplasia developing in a patient 9 years after the first of two allogeneic transplantations.

Lung cancers detected by screening with spiral computed tomography have a malignant phenotype when analyzed by cDNA microarray

PURPOSE

Spiral computed tomography (CT) can detect lung cancer at an early stage, but the malignant potential is unknown. The question is, as follows: do these small lesions have the same lethal potential as do symptomatic tumors?

EXPERIMENTAL DESIGN

We used a cDNA microarray platform and compared the gene expression profile of spiral CT-detected lung carcinomas with a matched case-control population of patients presenting with symptomatic lung cancer.

RESULTS

CT-detected and symptomatic tumors have shown a comparable gene expression profile. Correspondence analysis has demonstrated that nine genes were differentially expressed, although with a high variability across the samples that prevented distinguishing the two groups of tumors. Analysis of these nine genes has suggested that early-detected tumors have higher levels of retinoic acid production and higher expression levels of caveolin 2, matrix Gla, and cystatin A, which are already known to be lost during tumor progression.

CONCLUSIONS

All of the tumors observed are histologically malignant according to the WHO Classification. Early lung cancers that are detected by screening have a gene expression pattern similar to, but not identical to, that of symptomatic lung carcinomas.

Proliferative glomerulonephritis associated with mantle cell lymphoma – natural history and effect of treatment in 2 cases

We describe 2 patients with mantle cell lymphoma who presented with dialysis-dependent acute renal failure and in whom the renal biopsies showed proliferative glomerulonephritis. The first patient had lymphadenopathy and the second splenomegaly, but no cause was initially identified in either case. The first patient was treated with immunosuppressive drugs, the second was given no specific therapy; renal function recovered in both. However, more than 1 year later, both again became dialysis-dependent but had also developed generalized lymphadenopathy. A diagnosis of mantle cell non-Hodgkin's lymphoma was made in both cases. The association of active lymphoma and renal disease supports a paraneoplastic mechanism for the occurrence of the glomerulonephritis in these patients. The literature describing the association between non-Hodgkin's lymphoma and glomerulonephritis is reviewed.

Phosphorylated KDR is expressed in the neoplastic and stromal elements of human renal tumours and shuttles from cell membrane to nucleus

Vascular endothelial growth factor (VEGF)-A is an important angiogenic factor in establishing the vasculature in renal cell carcinomas (RCCs). Since little is known about VEGF signalling in RCCs, the profile of phosphorylated KDR (pKDR) has been investigated and the intracellular location of the receptor has been examined in the present study. Using two monoclonal antibodies raised against the phosphorylated KDR epitopes (Y1059 and Y1214) known to mediate different VEGF functions, together with a commercial anti-KDR antibody and immunohistochemistry, the expression of pKDR was investigated in a series of normal (n = 25) and neoplastic kidneys (n = 54; clear cell n = 35; papillary n = 10; oncocytomas n = 8). pKDR was present in many tissue elements of both normal and neoplastic renal tissues, with strong expression in the cell membrane, cytoplasm, and nuclei of normal kidney and tumour cells, as well as endothelial cells in tumours of all histological types. Patterns and intensity were similar using both anti-pKDR antibodies. There was no significant correlation in clear cell carcinomas between pKDR expression and age (p = 0.57), tumour size (p = 0.2), gender (p = 0.59), grade (p = 0.2) or histological type (p = 0.36). To delineate further the intracellular processing that might account for the cellular distribution, confocal microscopy was also performed. Antibodies to the different phosphorylated epitopes demonstrated different intracellular staining patterns. This study shows that pKDR is present in a wide variety of renal tumours, suggesting that anti-VEGF therapy might have direct effects on tumour cells. It further suggests that cells traffic pKDR depending on the precise KDR tyrosines that are autophosphorylated in a manner that enables receptor activation to result in different functions.

Plasmablastic lymphoma in HIV+ patients: an expanding spectrum

AIM

To describe an unusual human immunodeficiency virus (HIV)-associated lymphoma in uncommon sites. Plasmablastic lymphoma is a distinctive HIV-associated tumour that was first described in the jaws and oral cavity. Only two cases (stomach and lung) have been documented in extra-oral sites.

MATERIALS AND METHODS

Four cases were encountered in HIV+ patients: three in the anorectal region and one which was nasal and paranasal. The cases were routinely processed and immunohistochemistry was performed on formalin-fixed paraffin-embedded tissue.

RESULTS

The cases showed the typical morphological appearances of a high-grade, blastic non-Hodgkin's lymphoma (brisk mitotic activity and tingible body macrophages). In addition, some cells had a plasmacytoid appearance and paranuclear clearing. Immunophenotypically, the tumour cells were negative for LCA, CD20 and CD45RA. However, a small proportion of cells (5%) were immunoreactive for CD79a and the majority were positive with VS38c, indicative of plasma cell differentiation. Kappa light chain and IgG heavy chain restriction was also detected.

CONCLUSIONS

Plasmablastic lymphoma may occur in extra-oral sites and has a characteristic immunophenotype including focal expression of CD31 by the neoplastic cells. Awareness of the absence of expression of conventional B-cell markers and its presence in unusual sites should facilitate the diagnosis of plasmablastic lymphoma in HIV+ patients.

Vascular patterns in reactive lymphoid tissue and in non-Hodgkin's lymphoma

The few studies published on angiogenesis in lymphoma have raised the question of whether or not microvessel density (MVD) is associated with more aggressive disease and have reported the observation that in follicular lymphomas, vessels are mature rather than immature. We investigated MVD and the vascular phenotype within follicular or diffuse large B-cell lymphomas, reactive nodes and tonsils. Vascular phenotype was defined by the expression or loss of reactivity to the antibody LH39 (detecting the LH39 laminin epitope of the basement membrane in mature vessels) and by detection of alpha V beta 3 (expressed on immature vessels). In reactive nodes and in follicular lymphomas, MVD was higher in the paracortex than in germinal centres or in neoplastic follicles. However, in neoplastic follicles an increase in alpha V beta 3-positive endothelium suggested the activation of an angiogenic pathway different from that present in the reactive follicles. In large B-cell lymphomas, MVD was higher than in reactive and neoplastic follicles but lower than in the reactive paracortex. The number of immature vessels (LH39 negative) and of alpha V beta 3-positive vessels was higher than in reactive lymph nodes and follicular lymphoma suggesting that a switch to a different angiogenic pathway has occurred. Finally, we have demonstrated that within reactive and neoplastic follicles vascular regression is occurring, perhaps constraining the growth of reactive follicles alongside other phenomena such as apoptosis. Vascular regression was previously believed to occur in adults only in ovarian and endometrial tissue. We conclude that different types of angiogenesis are present in follicular lymphomas and large B-cell lymphomas. This has implications for possible future therapies.

Low-dose IFN-gamma induces tumor MHC expression in metastatic malignant melanoma

Specific antitumor immune responses require expression of MHC class I or II molecules on tumor cells, and MHC antigen down-regulation is a presumed tumor growth promoting mechanism. Because IFN-gamma up-regulates tumor MHC antigen expression in vitro, in this Phase II trial of an immunologically active dose and schedule we evaluated whether this was the case in vivo. Twenty-three patients with metastatic melanoma were treated with IFN-gamma 100 microg/m(2) s.c. once weekly for a maximum of 6 months. There were three complete responses, now maintained for 53, 36, and 25 months. The remainder had progressive disease. The treatment was well tolerated, with no toxicity exceeding National Cancer Institute Common Toxicity Criteria grade II. Immunohistochemical analysis of tumor biopsies during treatment was performed using monoclonal antibodies to HLA class I (W/632) and class II (CR3/43) monomorphic determinants. HLA class I was down-regulated in 2 of 19 patients pretreatment and up-regulated by IFN-gamma in both. HLA class II was down-regulated pretreatment in 14 of 18 patients and up-regulated by IFN-gamma in 6 (43%). The HLA up-regulation persisted throughout the study. IFN-gamma induced significant but short-lived up-regulation of surrogate markers of monocyte activation (serum neopterin) and class I up-regulation (serum beta-2-microglobulin) in most patients. There was no consistent relationship between surrogate marker up-regulation, tumor antigen up-regulation, and responses. The study shows that the significant immune modulation induced by IFN-gamma does not correlate with tumor responses and that the serum surrogate marker changes do not reflect tumor events. The durable and long-lived responses, clear demonstration of tumor MHC up-regulation, and low toxicity suggest that weekly IFN-gamma 100 microg/m(2) would be a useful addition to chemoimmunotherapeutic regimens.

p53 expression in normal paraffin-embedded tissue using different antibodies and antigen retrieval buffer systems

AIMS

The study was undertaken to demonstrate wild-type p53 in normal paraffin-embedded tissues using two widely used antibodies, DO7 and 1801 and two different antigen retrieval buffer systems.

METHODS AND RESULTS

Formalin-fixed paraffin-embedded normal tissue samples were obtained from the archives of the John Radcliffe Hospital, Oxford. Antigen retrieval was performed by microwaving using two different buffer systems: (i) the commercially available Dako target retrieval solution (Cat. no. 1699) (pH 9.8-9.9), (ii) freshly prepared buffer consisting of 0.1 m EDTA with 0.1% Tween pH 6.0, and (iii) freshly prepared buffer consisting of 0.1 m EDTA with 0.1% Tween pH 8.0. Staining was performed with DO7 and 1801 antibodies using the Dako Envision kit (peroxidase/DAB). DO7 antibody elicited strong nuclear staining in the mucosal cells of the small and large intestine, lymphoid cells, decidua, neurones such as Purkinje cells of the cerebellum, glandular epithelial cells and stromal cells of the prostate, cardiac myocytes and bronchial epithelial cells. Cytoplasmic staining was noted in Purkinje cells, glandular epithelium of prostate, exocrine pancreas and renal tubular epithelium. The 1801 antibody did not produce staining in any of these tissues.

CONCLUSIONS

Our study demonstrates the presence of p53 in normal paraffin-embedded tissue with nuclear and/or cytoplasmic localization in some instances. In our view, DO7 appears to be better suited for such detection.

Hypoxia-inducible factors HIF-1alpha and HIF-2alpha in head and neck cancer: relationship to tumor biology and treatment outcome in surgically resected patients

Hypoxia within head and neck squamous cell carcinoma (HNSCC) predicts a poor response to radiotherapy and poor prognosis. Hypoxia-inducible factor (HIF)-1 and HIF-2 are nuclear transcription factors that regulate the cellular response to hypoxia and are important for solid tumor growth and survival. Overexpression of HIF-1alpha and HIF-2alpha was demonstrated in three HNSCC cell lines under hypoxia and tumor tissue versus normal tissue (n = 20, HIF-1alpha, P = 0.023; HIF-2alpha, P = 0.013). On immunostaining, HIF-1alpha and HIF-2alpha expression were localized to tumor nuclei; HIF-2alpha expression was also seen in tumor-associated macrophages. Expression of HIF-1alpha in surgically treated patients with HNSCC (n = 79) was associated with improved disease-free survival (P = 0.016) and overall survival (P = 0.027).

Expression of angiogenic factors and hypoxia inducible factors HIF 1, HIF 2 and CA IX in non-Hodgkin's lymphoma

AIMS

Angiogenesis in solid tumour pathology is well established but less is known about its role in haematological malignancies. Our study investigated the immunohistochemical expression of a variety of angiogenic and hypoxic factors and microvessel densities on 110 cases of high- and low-grade non-Hodgkin's lymphomas and reactive lymphoid tissues. methods and results: Expression of vascular endothelial growth factor (VEGF) was present in 82 (96%) of the non-Hodgkin's cases and 35 (100%) of the reactive lymphoid tissue cases. Both hypoxia inducible factors 1 alpha and 2 alpha (HIF 1 alpha, 2 alpha) were weakly expressed in the majority of high- and low-grade lymphomas. Carbonic anhydrase IX (CA IX), a HIF-inducible membrane-bound enzyme, expression was not abundant with membranous staining being present in seven (8%) of the lymphoma cases and none of the reactive cases. Thymidine phosphorylase (TP) was distributed amongst macrophages and follicular dendritic cells but was not present in the neoplastic population. The vasculature was stained using CD34 which gave rise to a distinct vascular, predominantly paracortical network present in low-grade lymphomas and reactive lymphoid tissue but which was lost in high-grade lymphomas.

CONCLUSION

Our results suggest that non-Hodgkin's lymphomas may be less angiogenic and hypoxically driven than most solid tumours, which has implications for possible future therapies.

The FOXP1 winged helix transcription factor is a novel candidate tumor suppressor gene on chromosome 3p

The JC12 monoclonal antibody recognizes a previously unknown nuclear protein that showed a restricted distribution in normal tonsil and was also overexpressed in a subset of diffuse large B-cell lymphomas. Using this reagent, we expression cloned cDNAs encoding its antigenic target and identified this protein as a novel putative transcription factor, FOXP1. The FOXP1 protein sequence contains predicted domains characteristic of transcription factors, including a winged helix DNA-binding motif, a second potential DNA-binding motif, a C(2)H(2) zinc finger, nuclear localization signals, coiled-coil regions, PEST sequences, and potential transactivation domains. The FOXP1 gene has been mapped to chromosome 3p14.1, a region that commonly shows loss of heterozygosity in a wide range of tumors and which is reported to contain a tumor suppressor gene(s). Using tissue arrays and immunohistochemistry, we demonstrate that both the FOXP1 mRNA and protein are widely expressed in normal tissues. The levels of FOXP1 mRNA were compared in paired normal and tumor tissues (from the same patient) using a tissue array containing cDNAs extracted from 68 samples taken from kidney, breast, prostate, uterus, ovary, cervix, colon, lung, stomach, rectum, small intestine, and from nine cancer cell lines. Differences in FOXP1 mRNA expression between normal and tumor samples were observed in 51% of cases. Most striking was the comparative loss of expression in 73% of colon tumors and comparative overexpression of FOXP1 mRNA in 75% of stomach tumors. Analysis of the FOXP1 mRNA expression in normal tissues (not taken from cancer patients) indicated that loss of FOXP1 expression may occur in some histologically normal tissues adjacent to tumors. Immunohistochemical analysis of FOXP1 protein expression was performed on 128 solid tumors, including 16 renal, 9 breast, 12 lung, 20 colon, 21 stomach, 10 head and neck, 35 prostate, and 5 pancreatic cases. Complete loss of expression, increased expression, and cytoplasmic mislocalization of the predominantly nuclear FOXP1 protein were frequently observed in neoplastic cells. Our study identifies FOXP1 as a new candidate tumor suppressor gene localized to the chromosome 3p14.1 region.