Kathrine Woie

Landscape of genomic alterations in cervical carcinomas

Cervical cancer is responsible for 10–15% of cancer-related deaths in women worldwide. The aetiological role of infection with high-risk human papilloma viruses (HPVs) in cervical carcinomas is well established. Previous studies have also implicated somatic mutations in PIK3CA, PTEN, TP53, STK11 and KRAS as well as several copy-number alterations in the pathogenesis of cervical carcinomas. Here we report whole-exome sequencing analysis of 115 cervical carcinoma–normal paired samples, transcriptome sequencing of 79 cases and whole-genome sequencing of 14 tumour–normal pairs. Previously unknown somatic mutations in 79 primary squamous cell carcinomas include recurrent E322K substitutions in the MAPK1 gene (8%), inactivating mutations in the HLA-B gene (9%), and mutations in EP300 (16%), FBXW7 (15%), NFE2L2 (4%), TP53 (5%) and ERBB2 (6%). We also observe somatic ELF3 (13%) and CBFB (8%) mutations in 24 adenocarcinomas. Squamous cell carcinomas have higher frequencies of somatic nucleotide substitutions occurring at cytosines preceded by thymines (Tp*C sites) than adenocarcinomas. Gene expression levels at HPV integration sites were statistically significantly higher in tumours with HPV integration compared with expression of the same genes in tumours without viral integration at the same site. These data demonstrate several recurrent genomic alterations in cervical carcinomas that suggest new strategies to combat this disease.

The genomic landscape and evolution of endometrial carcinoma progression and abdominopelvic metastasis

Recent studies have detailed the genomic landscape of primary endometrial cancers, but the evolution of these cancers into metastases has not been characterized. We performed whole-exome sequencing of 98 tumor biopsies including complex atypical hyperplasias, primary tumors and paired abdominopelvic metastases to survey the evolutionary landscape of endometrial cancer. We expanded and reanalyzed The Cancer Genome Atlas (TCGA) data, identifying new recurrent alterations in primary tumors, including mutations in the estrogen receptor cofactor gene NRIP1 in 12% of patients. We found that likely driver events were present in both primary and metastatic tissue samples, with notable exceptions such as ARID1A mutations. Phylogenetic analyses indicated that the sampled metastases typically arose from a common ancestral subclone that was not detected in the primary tumor biopsy. These data demonstrate extensive genetic heterogeneity in endometrial cancers and relative homogeneity across metastatic sites.

A New Method for Isolation of Interstitial Fluid from Human Solid Tumors Applied to Proteomic Analysis of Ovarian Carcinoma Tissue

Major efforts have been invested in the identification of cancer biomarkers in plasma, but the extraordinary dynamic range in protein composition, and the dilution of disease specific proteins make discovery in plasma challenging. Focus is shifting towards using proximal fluids for biomarker discovery, but methods to verify the isolated samples origin are missing. We therefore aimed to develop a technique to search for potential candidate proteins in the proximal proteome, i.e. in the tumor interstitial fluid, since the biomarkers are likely to be excreted or derive from the tumor microenvironment. Since tumor interstitial fluid is not readily accessible, we applied a centrifugation method developed in experimental animals and asked whether interstitial fluid from human tissue could be isolated, using ovarian carcinoma as a model. Exposure of extirpated tissue to 106 g enabled tumor fluid isolation. The fluid was verified as interstitial by an isolated fluid:plasma ratio not significantly different from 1.0 for both creatinine and Na+, two substances predominantly present in interstitial fluid. The isolated fluid had a colloid osmotic pressure 79% of that in plasma, suggesting that there was some sieving of proteins at the capillary wall. Using a proteomic approach we detected 769 proteins in the isolated interstitial fluid, sixfold higher than in patient plasma. We conclude that the isolated fluid represents undiluted interstitial fluid and thus a subproteome with high concentration of locally secreted proteins that may be detected in plasma for diagnostic, therapeutic and prognostic monitoring by targeted methods.

Transcervical endometrial resection : Long-term results of 390 procedures

Background. Hysteroscopic transcervical resection of the endometrium and submucous fibroids has been performed to treat excessive uterine bleeding as an alternative to hysterectomy. The present study aims to evaluate the treatment effect of this procedure at our department. Methods. Retrospective record review and a questionnaire 4–10 years after surgery. Patients’ characteristics, symptoms, medical treatment prior to surgery, uterine size, weight of resectate, blood loss, glycine loss, operative time, complications, procedures per surgeon, indications, frequency and time to hysterectomy, dysmenorrhea related to prior tubal ligation, the presence of adenomyosis related to later hysterectomy, and patient satisfaction. Results. In the period 1992–1998, 386 patients had 390 procedures performed by six different surgeons. 49.5% of patients had fibroids and 46.9% had a prior tubal sterilization. During operations, 6% had a hemoglobin loss of more than 2.5 g/dl, and 2.1% had a glycine loss of more than 1.5 l. Uterine perforations were encountered in 31 cases (8%), of which only 2 led to a laparotomy. During the time of follow‐up of 4–10 years, 16.6% of patients had a hysterectomy, usually because of pain or bleeding, and 50% of these were done within 2 years after the initial hysteroscopic procedure. Malignancy was found in the resectate in 6 of the patients (1.5%) despite a normal preoperative cytological or histological endometrial sample, and all these had a hysterectomy. Adenomyosis was not related to later hysterectomy and dysmenorrhea did not seem to increase after the procedure. Conclusions. For 83.4% of the patients, the problem of uterine bleeding was solved by the hysteroscopic resection, and major surgery was avoided. Long‐term results did not correlate to surgeons experience. Patient satisfaction was high.

Corticotropin-releasing hormone inhibits lowering of interstitial pressure in rat trachea after neurogenic inflammation

Increased negativity of interstitial fluid pressure (Pif) is a key determinant of edema formation after tissue injury. In this study, we addressed the question of whether the anti-inflammatory effects of corticotropin-releasing hormone (CRH) shown by others are mediated by changes in interstitial fluid pressure. CRH, 25 to 50, but not 5 and 11 microg/kg s.c., administered 45 min before antidromic stimulation of the vagal nerve inhibited the lowering of interstitial fluid pressure in rat trachea produced by nerve stimulation. This inhibitory effect of CRH was blocked by pretreatment with the CRH receptor antagonist, alpha-helical CRH-(9-41), 0.15 mg/kg i.v., administered 5 min before CRH. These results suggest that CRH receptors modulate the structural integrity of the extracellular matrix in rat trachea for its response to inflammatory stimuli.

Impact of secondary cytoreductive surgery on survival in patients with platinum sensitive recurrent ovarian cancer: Analysis of the CALYPSO trial

OBJECTIVE The role of secondary cytoreductive surgery (SCR) in platinum-sensitive recurrent ovarian cancer (ROC) remains controversial. The overall survival (OS) benefits for surgery reported in observational studies may be due to the selection of patients with better prognosis. METHODS Using data from the CALYPSO trial, OS of patients who had SCR was compared to those treated with chemotherapy alone. Multivariate analyses were performed to adjust for prognostic factors. We also tested for an interaction between baseline prognostic groupings and the benefit of surgery. RESULTS Of the 975 patients randomised in CALYPSO, 19% had SCR and 80% had chemotherapy alone. OS was longer for the SCR group than for chemotherapy alone (median, 49.9 vs. 29.7 months; adjusted hazard ratio (HR), 0.68; P = 0.004). For patients with SCR, the 3-year OS was 72% for those with no measurable disease, and 28% if residual tumour was larger than 5 cm. Patients with good prognostic features benefited the most from SCR (HR 0.43; P < 0.001). The benefit of SCR was less in patients with poorer prognostic features (test of trend P < 0.001). CONCLUSION SCR was associated with improved OS in platinum-sensitive ROC, particularly in patients with favourable prognostic characteristics. However, these findings may be due to selection bias, and hence randomised trials are still essential.

Increased WD-repeat containing protein 1 in interstitial fluid from ovarian carcinomas shown by comparative proteomic analysis of malignant and healthy gynecological tissue ☆

We aimed to identify differentially expressed proteins in interstitial fluid from ovarian cancer employing multiple fractioning and high resolution mass spectrometry-based proteomic analysis, and asked whether specific proteins that may serve as biomarker candidates or therapeutic targets could be identified. High throughput proteomics was conducted on immunodepleted and fractioned interstitial fluid from pooled samples of ovarian carcinomas, using endometrial carcinomas and healthy ovarian tissue as controls. Differential analysis revealed the up-regulation of extracellular proteasomes in tumor interstitial fluid compared to the healthy control. Moreover, a number of differentially expressed proteins in interstitial fluid from ovarian carcinomas compared with control tissues were identified. Detection of proteasome 20S related proteins in TIF compared to IF from healthy tissue indicates that the 20S proteasome can have a role in the tumor microenvironment. Six selected proteins, CEACAM5, FREM2, MUC5AC, TFF3, PYCARD and WDR1, were independently validated in individual tumor lysates from ovarian carcinomas by multiple reaction monitoring initiated detection and sequence analysis, Western blot and/or selected reaction monitoring. Quantification of specific proteins revealed substantial heterogeneity between individual samples. Nevertheless, WD repeat-containing protein 1 was confirmed as being significantly overexpressed in interstitial fluid from ovarian carcinomas compared to healthy ovarian tissue by Orbitrap analysis of individual native interstitial fluid from ovarian and endometrial carcinomas and healthy ovarian tissue. We suggest that this protein should be explored as a therapeutic target in ovarian carcinomas. This article is part of a Special Issue entitled: An Updated Secretome.

Tissue and imaging biomarkers for hypoxia predict poor outcome in endometrial cancer

Hypoxia is frequent in solid tumors and linked to aggressive phenotypes and therapy resistance. We explored expression patterns of the proposed hypoxia marker HIF-1α in endometrial cancer (EC) and investigate whether preoperative functional imaging parameters are associated with tumor hypoxia. Expression of HIF-1α was explored both in the epithelial and the stromal tumor component. We found that low epithelial HIF-1α and high stromal HIF-1α expression were significantly associated with reduced disease specific survival in EC. Only stromal HIF-1α had independent prognostic value in Cox regression analysis. High stromal HIF-1α protein expression was rare in the premalignant lesions of complex atypical hyperplasia but increased significantly to invasive cancer. High stromal HIF-1α expression was correlated with overexpression of important genes downstream from HIF-1α, i.e. VEGFA and SLC2A1 (GLUT1). Detecting hypoxic tumors with preoperative functional imaging might have therapeutic benefits. We found that high stromal HIF-1α expression associated with high total lesion glycolysis (TLG) at PET/CT. High expression of a gene signature linked to hypoxia also correlated with low tumor blood flow at DCE-MRI and increased metabolism measured by FDG-PET. PI3K pathway inhibitors were identified as potential therapeutic compounds in patients with lesions overexpressing this gene signature. In conclusion, we show that high stromal HIF-1α expression predicts reduced survival in EC and is associated with increased tumor metabolism at FDG-PET/CT. Importantly; we demonstrate a correlation between tissue and imaging biomarkers reflecting hypoxia, and also possible treatment targets for selected patients.

Distribution volumes of macromolecules in human ovarian and endometrial cancers--effects of extracellular matrix structure.

Elements of the extracellular matrix (ECM), notably collagen and glucosaminoglycans, will restrict part of the space available for soluble macromolecules simply because the molecules cannot occupy the same space. This phenomenon may influence macromolecular drug uptake. To study the influence of steric and charge effects of the ECM on the distribution volumes of macromolecules in human healthy and malignant gynecologic tissues we used as probes 15 abundant plasma proteins quantified by high-resolution mass spectrometry. The available distribution volume (VA) of albumin was increased in ovarian carcinoma compared with healthy ovarian tissue. Furthermore, VA of plasma proteins between 40 and 190 kDa decreased with size for endometrial carcinoma and healthy ovarian tissue, but was independent of molecular weight for the ovarian carcinomas. An effect of charge on distribution volume was only found in healthy ovaries, which had lower hydration and high collagen content, indicating that a condensed interstitium increases the influence of negative charges. A number of earlier suggested biomarker candidates were detected in increased amounts in malignant tissue, e.g., stathmin and spindlin-1, showing that interstitial fluid, even when unfractionated, can be a valuable source for tissue-specific proteins. We demonstrate that the distribution of abundant plasma proteins in the interstitium can be elucidated by mass spectrometry methods and depends markedly on hydration and ECM structure. Our data can be used in modeling of drug uptake, and give indications on ECM components to be targeted to increase the uptake of macromolecular substances.

Chemotherapy vs tamoxifen in platinum-resistant ovarian cancer : A phase III, randomised, multicentre trial (Ovaresist)

Background:Chemotherapy in platinum-resistant ovarian cancer (PROC) aims for palliation and prolonging of progression-free survival (PFS). This study compares Health-related Quality of Life (HRQoL) and efficacy between single-agent chemotherapy and tamoxifen in PROC.Methods:Patients with PROC were randomised (2 : 1) to chemotherapy (weekly paclitaxel 80 mg m−2 or four weekly pegylated liposomal doxorubicin 40 mg m−2) or tamoxifen 40 mg daily. The primary end point was HRQoL. Secondary end points were PFS by RECIST and overall survival (OS).Results:Between March 2002 and December 2007, 156 and 82 patients were randomised to chemotherapy and tamoxifen, respectively. In the chemotherapy arm, a significantly larger proportion of patients experienced a worsening in their social functioning. There was no difference in the proportion of patients experiencing improvement of gastrointestinal symptoms. Median PFS on tamoxifen was 8.3 weeks (95% CI, 8.0–10.4) compared with 12.7 weeks (95% CI, 9.0–16.3) on chemotherapy (HR, 1.54; 95% CI, 1.16–2.05; log-rank P=0.003). There was no difference in OS between the treatment arms.Conclusions:Patients on chemotherapy had longer PFS but experienced more toxicity and poorer HRQoL compared with tamoxifen. Control over gastrointestinal symptoms was not better on chemotherapy. These data are important for patient counselling and highlight the need to incorporate HRQoL end points in studies of PROC.