Radiomic profiles improve prognostication and reveal targets for therapy in cervical cancer

Cervical cancer (CC) is a major global health problem with 570,000 new cases and 266,000 deaths annually. Prognosis is poor for advanced stage disease, and few effective treatments exist. Preoperative diagnostic imaging is common in high-income countries and MRI measured tumor size routinely guides treatment allocation of cervical cancer patients. Recently, the role of MRI radiomics has been recognized. However, its potential to independently predict survival and treatment response requires further clarification. This retrospective cohort study demonstrates how non-invasive, preoperative, MRI radiomic profiling may improve prognostication and tailoring of treatments and follow-ups for cervical cancer patients. By unsupervised clustering based on 293 radiomic features from 132 patients, we identify three distinct clusters comprising patients with significantly different risk profiles, also when adjusting for FIGO stage and age. By linking their radiomic profiles to genomic alterations, we identify putative treatment targets for the different patient clusters (e.g., immunotherapy, CDK4/6 and YAP-TEAD inhibitors and p53 pathway targeting treatments).

Clinicopathological and radiological stratification within FIGO 2018 stages improves risk-prediction in cervical cancer

OBJECTIVE

Assess the added prognostic value of the updated International Federation of Gynecology and Obstetrics (FIGO) 2018 staging system, and to identify clinicopathological and radiological biomarkers for improved FIGO 2018 prognostication.

METHODS

Patient data were retrieved from a prospectively collected patient cohort including all consenting patients with cervical cancer diagnosed and treated at Haukeland University Hospital during 2001-2022 (n = 948). All patients were staged according to the FIGO 2009 and FIGO 2018 guidelines based on available data for individual patients. MRI-assessed maximum tumor diameter and stromal tumor invasion, as well as histopathologically assessed lymphovascular space invasion were applied to categorize patients according to the Sedlis criteria.

RESULTS

FIGO 2018 stage yielded the highest area under the receiver operating characteristic (ROC) curve (AUC) (0.86 versus 0.81 for FIGO 2009) for predicting disease-specific survival. The most common stage migration in FIGO 2018 versus FIGO 2009 was upstaging from stages IB/II to stage IIIC due to suspicious lymph nodes identified by PET/CT and/or MRI. In FIGO 2018 stage III patients, extent and size of primary tumor (p = 0.04), as well as its histological type (p = 0.003) were highly prognostic. Sedlis criteria were prognostic within FIGO 2018 IB patients (p = 0.04).

CONCLUSIONS

Incorporation of cross-sectional imaging increases prognostic precision, as suggested by the FIGO 2018 guidelines. The 2018 FIGO IIIC stage could be refined by including the size and extent of primary tumor and histological type. The FIGO IB risk prediction could be improved by applying MRI-assessed tumor size and stromal invasion.

MRI-based radiomic signatures for pretreatment prognostication in cervical cancer

BACKGROUND

Accurate pretherapeutic prognostication is important for tailoring treatment in cervical cancer (CC).

PURPOSE

To investigate whether pretreatment MRI-based radiomic signatures predict disease-specific survival (DSS) in CC.

STUDY TYPE

Retrospective.

POPULATION

CC patients (n = 133) allocated into training(T) (nT  = 89)/validation(V) (nV  = 44) cohorts.

FIELD STRENGTH/SEQUENCE

T2-weighted imaging (T2WI) and diffusion-weighted imaging (DWI) at 1.5T or 3.0T.

ASSESSMENT

Radiomic features from segmented tumors were extracted from T2WI and DWI (high b-value DWI and apparent diffusion coefficient (ADC) maps).

STATISTICAL TESTS

Radiomic signatures for prediction of DSS from T2WI (T2rad ) and T2WI with DWI (T2 + DWIrad ) were constructed by least absolute shrinkage and selection operator (LASSO) Cox regression. Area under time-dependent receiver operating characteristics curves (AUC) were used to evaluate and compare the prognostic performance of the radiomic signatures, MRI-derived maximum tumor size ≤/> 4 cm (MAXsize ), and 2018 International Federation of Gynecology and Obstetrics (FIGO) stage (I-II/III-IV). Survival was analyzed using Cox model estimating hazard ratios (HR) and Kaplan-Meier method with log-rank tests.

RESULTS

The radiomic signatures T2rad and T2 + DWIrad yielded AUCT /AUCV of 0.80/0.62 and 0.81/0.75, respectively, for predicting 5-year DSS. Both signatures yielded better or equal prognostic performance to that of MAXsize (AUCT /AUCV : 0.69/0.65) and FIGO (AUCT /AUCV : 0.77/0.64) and were significant predictors of DSS after adjusting for FIGO (HRT /HRV for T2rad : 4.0/2.5 and T2 + DWIrad : 4.8/2.1). Adding T2rad and T2 + DWIrad to FIGO significantly improved DSS prediction compared to FIGO alone in cohort(T) (AUCT 0.86 and 0.88 vs. 0.77), and FIGO with T2 + DWIrad tended to the same in cohort(V) (AUCV 0.75 vs. 0.64, p = 0.07). High radiomic score for T2 + DWIrad was significantly associated with reduced DSS in both cohorts.

DATA CONCLUSION

Radiomic signatures from T2WI and T2WI with DWI may provide added value for pretreatment risk assessment and for guiding tailored treatment strategies in CC.

Mismatch repair markers in preoperative and operative endometrial cancer samples; expression concordance and prognostic value

BACKGROUND

The endometrial cancer mismatch repair (MMR) deficient subgroup is defined by loss of MSH6, MSH2, PMS2 or MLH1. We compare MMR status in paired preoperative and operative samples and investigate the prognostic impact of differential MMR protein expression levels.

METHODS

Tumour lesions from 1058 endometrial cancer patients were immunohistochemically stained for MSH6, MSH2, PMS2 and MLH1. MMR protein expression was evaluated as loss or intact to determine MMR status, or by staining index to evaluate the prognostic potential of differential expression. Gene expression data from a local (n = 235) and the TCGA (n = 524) endometrial cancer cohorts was used for validation.

RESULTS

We identified a substantial agreement in MMR status between paired curettage and hysterectomy samples. Individual high expression of all four MMR markers associated with non-endometrioid subtype, and high MSH6 or MSH2 strongly associated with several aggressive disease characteristics including high tumour grade and FIGO stage, and for MSH6, with lymph node metastasis. In multivariate Cox analysis, MSH6 remained an independent prognostic marker, also within the endometrioid low-grade subgroup (P < 0.001).

CONCLUSION

We demonstrate that in addition to determine MMR status, MMR protein expression levels, particularly MSH6, may add prognostic information in endometrial cancer.

What MRI-based tumor size measurement is best for predicting long-term survival in uterine cervical cancer?

Background

Tumor size assessment by MRI is central for staging uterine cervical cancer. However, the optimal role of MRI-derived tumor measurements for prognostication is still unclear.

Material and methods

This retrospective cohort study included 416 women (median age: 43 years) diagnosed with cervical cancer during 2002–2017 who underwent pretreatment pelvic MRI. The MRIs were independently read by three radiologists, measuring maximum tumor diameters in three orthogonal planes and maximum diameter irrespective of plane (MAX_imaging). Inter-reader agreement for tumor size measurements was assessed by intraclass correlation coefficients (ICCs). Size was analyzed in relation to age, International Federation of Gynecology and Obstetrics (FIGO) (2018) stage, histopathological markers, and disease-specific survival using Kaplan–Meier-, Cox regression-, and time-dependent receiver operating characteristics (tdROC) analyses.

Results

All MRI tumor size variables (cm) yielded high areas under the tdROC curves (AUCs) for predicting survival (AUC 0.81–0.84) at 5 years after diagnosis and predicted outcome (hazard ratios [HRs] of 1.42–1.76, p < 0.001 for all). Only MAX_imaging independently predicted survival (HR = 1.51, p = 0.03) in the model including all size variables. The optimal cutoff for maximum tumor diameter (≥ 4.0 cm) yielded sensitivity (specificity) of 83% (73%) for predicting disease-specific death after 5 years. Inter-reader agreement for MRI-based primary tumor size measurements was excellent, with ICCs of 0.83–0.85.

Conclusion

Among all MRI-derived tumor size measurements, MAX_imaging was the only independent predictor of survival. MAX_imaging ≥ 4.0 cm represents the optimal cutoff for predicting long-term disease-specific survival in cervical cancer. Inter-reader agreement for MRI-based tumor size measurements was excellent.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13244-022-01239-y.

Abstract 513: Radiomic profiles revealing targets for therapy in cervical cancer

Magnetic resonance imaging (MRI) has emerged as an important part of the diagnostic work-up in cervical cancer, with tumor volume and extent as important prognosticators. MRI radiomic tumor features may aid in prognostication and tailoring of treatment in cervical cancer. We extracted whole-volume radiomic texture features from 124 manually segmented tumors and performed unsupervised clustering yielding two distinct clusters. Overlapping clinicopathologic, genomic (whole exome sequencing, n=61), transcriptomic (L1000 arrays, n= 65) and molecular biomarker (n=82) data were applied to characterize the clusters. Independent of tumor size parameters, patients in cluster II had significantly reduced disease-specific survival as compared to those in cluster I (p&gt;0.001), also within squamous cell carcinomas (n=96, p&lt;0.001). Cluster II associated with high age (p=0.02), high FIGO-2009 stage (p&lt;0.001), high BMI (p=0.03) and PR negative tumors (p=0.004). Distinct mutational and copy-number profiles were detected for the two clusters. By gene set enrichment analyses, gene sets associated to immune activation were enriched in cluster I tumors, whilst gene sets associated with oxidative phosphorylation and epithelial to mesenchymal transition associated to cluster II tumors. This study links radiomic signatures to distinct genomic profiles that may potentially aid in prognostication and tailoring of treatments in cervical cancer patients.

Citation Format: Mari Kyllesø Halle, Erlend Hodneland, Erling Hoivik, Kari Wagner-Larsen, Njål G. Lura, Julie Dybvik, David Forsse, Bjørn I. Bertelsen, Camilla Krakstad, Ingfrid S. Haldorsen, Olivera Bozickovic, Kathrine Woie. Radiomic profiles revealing targets for therapy in cervical cancer [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 513.

Longitudinal effects of adjuvant chemotherapy and lymph node staging on patient-reported outcomes in endometrial cancer survivors: a prospective cohort study

BACKGROUND

Most patients with endometrial cancer with localized disease are effectively treated and survive for a long time. The primary treatment is hysterectomy, to which surgical staging procedures may be added to assess the need for adjuvant therapy. Longitudinal data on patient-reported outcomes comparing different levels of primary treatment are lacking, especially when adjuvant radiotherapy is omitted.

OBJECTIVE

We assessed the impact of lymphadenectomy and adjuvant chemotherapy on patient-reported symptoms, function, and quality of life. We hypothesized that these treatment modalities would substantially affect patient-reported outcomes at follow-up.

STUDY DESIGN

We prospectively included patients with endometrial cancer enrolled in the ongoing MoMaTEC2 study (ClinicalTrials.gov Identifier: NCT02543710). Patients were asked to complete the patient-reported outcome questionnaires European Organization for Research and Treatment of Cancer Quality of Life Questionnaire C30 and European Organization for Research and Treatment of Cancer Quality of Life Questionnaire EN24 preoperatively and at 1 and 2 years of follow-up. Functional domains and symptoms were analyzed for the whole cohort and by treatment received. To assess the effect of the individual treatment modifications, we used mixed regression models.

RESULTS

Baseline data were available for 448 patients. Of these patients, 339 and 219 had reached 1-year follow-up and 2-year follow-up, respectively. Treatment included hysterectomy (plus bilateral salpingo-oophorectomy) alone (n=177), hysterectomy and lymph node staging without adjuvant therapy (n=133), or adjuvant chemotherapy irrespective of staging procedure (n=138). Overall, patients reported improved global health status and quality of life (+9 units; P<.001), increased emotional and social functioning, and increased sexual interest and activity (P<.001 for all) from baseline to year 1, and these outcomes remained stable at year 2. Means of functional scales and quality of life were similar to age- and sex-weighted reference cohorts. Mean tingling and numbness and lymphedema increased after treatment. The group who received adjuvant chemotherapy had a larger mean reduction in physical functioning (-6 vs +2; P=.002) at year 1, more neuropathy (+30 vs +5; P<.001; year 1) at years 1 and 2, and more lymphedema at year 1 (+11 vs +2; P=.007) than the group treated with hysterectomy and salpingo-oophorectomy only. In patients not receiving adjuvant chemotherapy, patient-reported outcomes were similar regardless of lymph node staging procedures. Adjuvant chemotherapy independently increased fatigue, lymphedema, and neuropathy in mixed regression models.

CONCLUSION

Patients with endometrial cancer receiving adjuvant chemotherapy reported significantly reduced functioning and more symptoms up to 2 years after treatment. For patients treated by surgery alone, surgical staging did not seem to affect the quality of life or symptoms to a measurable degree at follow-up. Therefore, subjecting patients to lymph node removal to tailor adjuvant therapy seems justified from the patient's viewpoint; however, efforts should increase to find alternatives to traditional chemotherapy.

A Gene Signature Identifying CIN3 Regression and Cervical Cancer Survival

The purpose of this study was to establish a gene signature that may predict CIN3 regression and that may aid in selecting patients who may safely refrain from conization. Oncomine mRNA data including 398 immune-related genes from 21 lesions with confirmed regression and 28 with persistent CIN3 were compared. L1000 mRNA data from a cervical cancer cohort was available for validation (n = 239). Transcriptomic analyses identified TDO2 (p = 0.004), CCL5 (p < 0.001), CCL3 (p = 0.04), CD38 (p = 0.02), and PRF1 (p = 0.005) as upregulated, and LCK downregulated (p = 0.01) in CIN3 regression as compared to persistent CIN3 lesions. From these, a gene signature predicting CIN3 regression with a sensitivity of 91% (AUC = 0.85) was established. Transcriptomic analyses revealed proliferation as significantly linked to persistent CIN3. Within the cancer cohort, high regression signature score associated with immune activation by Gene Set enrichment Analyses (GSEA) and immune cell infiltration by histopathological evaluation (p < 0.001). Low signature score was associated with poor survival (p = 0.007) and large tumors (p = 0.01). In conclusion, the proposed six-gene signature predicts CIN regression and favorable cervical cancer prognosis and points to common drivers in precursors and cervical cancer lesions.

A 10-gene prognostic signature points to LIMCH1 and HLA-DQB1 as important players in aggressive cervical cancer disease

BACKGROUND

Advanced cervical cancer carries a particularly poor prognosis, and few treatment options exist. Identification of effective molecular markers is vital to improve the individualisation of treatment. We investigated transcriptional data from cervical carcinomas related to patient survival and recurrence to identify potential molecular drivers for aggressive disease.

METHODS

Primary tumour RNA-sequencing profiles from 20 patients with recurrence and 53 patients with cured disease were compared. Protein levels and prognostic impact for selected markers were identified by immunohistochemistry in a population-based patient cohort.

RESULTS

Comparison of tumours relative to recurrence status revealed 121 differentially expressed genes. From this gene set, a 10-gene signature with high prognostic significance (p = 0.001) was identified and validated in an independent patient cohort (p = 0.004). Protein levels of two signature genes, HLA-DQB1 (n = 389) and LIMCH1 (LIM and calponin homology domain 1) (n = 410), were independent predictors of survival (hazard ratio 2.50, p = 0.007 for HLA-DQB1 and 3.19, p = 0.007 for LIMCH1) when adjusting for established prognostic markers. HLA-DQB1 protein expression associated with programmed death ligand 1 positivity (p < 0.001). In gene set enrichment analyses, HLA-DQB1high tumours associated with immune activation and response to interferon-γ (IFN-γ).

CONCLUSIONS

This study revealed a 10-gene signature with high prognostic power in cervical cancer. HLA-DQB1 and LIMCH1 are potential biomarkers guiding cervical cancer treatment.

Maintained survival outcome after reducing lymphadenectomy rates and optimizing adjuvant treatment in endometrial cancer

OBJECTIVE

Main controversies in endometrial cancer treatment include the role of lymphadenectomy and optimal adjuvant treatment. We assessed clinical outcome in a population-based endometrial cancer cohort in relation to changes in treatment management over two decades.

METHODS

All consenting endometrial cancer patients receiving primary treatment at Haukeland University Hospital from 2001 to 2019 were included (n = 1308). Clinicopathological variables were evaluated for year-to-year changes. Clinical outcome before and after discontinuing adjuvant radiotherapy and individualizing extent of lymphadenectomy was analyzed.

RESULTS

The rate of lymphadenectomy was reduced from 78% in 2001-2012 to 53% in 2013-2019. The rate of patients with verified lymph node metastases was maintained (9% vs 8%, p = 0.58) and FIGO stage I patients who did not undergo lymphadenectomy had stable 3-year recurrence-free survival (88% vs 90%, p = 0.67). Adjuvant chemotherapy for completely resected FIGO stage III patients increased from 27% to 97% from 2001 to 2009 to 2010-2019, while adjuvant radiotherapy declined from 57% to 0% (p < 0.001). These patients had improved 5-year overall- and recurrence-free survival; 0.49 [95% CI: 0.37-0.65] in 2001-2009 compared to 0.61 [0.45-0.83] in 2010-2019, p = 0.04 and 0.51 [0.39-0.68] to 0.71 [0.60-0.85], p = 0.03, respectively. For stage I, II and IV, survival rates were unchanged.

CONCLUSIONS

Our study demonstrates that preoperative stratification by imaging and histological assessments permits a reduction in lymphadenectomy to around 50%, and is achievable without an increase in recurrences at 3 years. In addition, our findings support that adjuvant chemotherapy alone performs equally to adjuvant radiotherapy with regard to survival, and is likely superior in advanced stage patients.

Niraparib Maintenance Treatment Improves Time Without Symptoms or Toxicity (TWiST) Versus Routine Surveillance in Recurrent Ovarian Cancer: A TWiST Analysis of the ENGOT-OV16/NOVA Trial

PURPOSE

This study estimated time without symptoms or toxicity (TWiST) with niraparib compared with routine surveillance (RS) in the maintenance treatment of patients with recurrent ovarian cancer.

PATIENTS AND METHODS

Mean progression-free survival (PFS) was estimated for niraparib and RS by fitting parametric survival distributions to Kaplan-Meier data for 553 patients with recurrent ovarian cancer who were enrolled in the phase III ENGOT-OV16/NOVA trial. Patients were categorized according to the presence or absence of a germline BRCA mutation—gBRCAmut and non-gBRCAmut cohorts. Mean time with toxicity was estimated based on the area under the Kaplan-Meier curve for symptomatic grade 2 or greater fatigue, nausea, and vomiting adverse events (AEs). Time with toxicity was the number of days a patient experienced an AE post–random assignment and before disease progression. TWiST was estimated as the difference between mean PFS and time with toxicity. Uncertainty was explored using alternative PFS estimates and considering all symptomatic grade 2 or greater AEs.

RESULTS

In the gBRCAmut and non-gBRCAmut cohorts, niraparib treatment resulted in a mean PFS benefit of 3.23 years and 1.44 years, respectively, and a mean time with toxicity of 0.28 years and 0.10 years, respectively, compared with RS. Hence, niraparib treatment resulted in a mean TWiST benefit of 2.95 years and 1.34 years, respectively, compared with RS, which is equivalent to more than four-fold and two-fold increases in mean TWiST between niraparib and RS in the gBRCAmut and non-gBRCAmut cohorts, respectively. This TWiST benefit was consistent across all sensitivity analyses, including modeling PFS over 5-, 10-, and 15-year time horizons.

CONCLUSION

Patients who were treated with niraparib compared with RS experienced increased mean TWiST. Thus, patients who were treated with niraparib in the ENGOT-OV16/NOVA trial experienced more time without symptoms or symptomatic toxicities compared with control.

Niraparib Maintenance Therapy in Patients With Recurrent Ovarian Cancer After a Partial Response to the Last Platinum-Based Chemotherapy in the ENGOT-OV16/NOVA Trial

PURPOSE

In the ENGOT-OV16/NOVA trial (ClinicalTrials.gov identifier: NCT01847274), maintenance therapy with niraparib, a poly(ADP-ribose) polymerase inhibitor, prolonged progression-free survival in patients with platinum-sensitive, recurrent ovarian cancer who had a response to their last platinum-based chemotherapy. The objective of the study was to assess the clinical benefit and patient-reported outcomes in patients who had a partial response (PR) and complete response (CR) to their last platinum-based therapy.

PATIENTS AND METHODS

A total of 553 patients were enrolled in the trial. Of 203 patients with a germline BRCA mutation (gBRCAmut), 99 had a PR and 104 had a CR to their last platinum-based therapy; of 350 patients without a confirmed gBRCAmut (non–gBRCAmut), 173 had a PR and 177 had a CR. Post hoc analyses were carried out to evaluate safety and the risk of progression in these patients according to gBRCAmut status and response to their last platinum-based therapy. Ovarian cancer–specific symptoms and quality of life were assessed using the Functional Assessment of Cancer Therapy–Ovarian Symptom Index.

RESULTS

Progression-free survival was improved in patients treated with niraparib compared with placebo in both the gBRCAmut cohort (PR: hazard ratio [HR], 0.24; 95% CI, 0.131 to 0.441; P < .0001; CR: HR, 0.30; 95% CI, 0.160 to 0.546; P < .0001) and the non–gBRCAmut cohort (PR: HR, 0.35; 95% CI, 0.230 to 0.532; P < .0001; CR: HR, 0.58; 95% CI, 0.383 to 0.868; P = .0082). The incidence of any-grade and grade 3 or greater adverse events was manageable. No meaningful differences were observed between niraparib and placebo in PR and CR subgroups with respect to patient-reported outcomes.

CONCLUSION

Patients achieved clinical benefit from maintenance treatment with niraparib regardless of response to the last platinum-based therapy.

In vivo MR spectroscopy predicts high tumor grade in endometrial cancer

Background In vivo magnetic resonance spectroscopy (MRS) enables non-invasive measurements of tumor metabolites. Choline-containing metabolites play a key role in tumor metabolism. Purpose To explore whether preoperative MRS-derived tumor choline levels are associated with clinical and histological features in endometrial carcinomas. Material and Methods Preoperative pelvic magnetic resonance imaging (MRI) (1.5T), including structural and diffusion-weighted imaging and localized multivoxel proton MR (1H-MR) spectroscopy, was performed in 77 prospectively included patients with histologically confirmed endometrial carcinomas. Relative levels of total choline-containing metabolites (tCho) in tumor and myometrium were measured using the ratios: tCho/Creatine; tCho/Water; and tCho/Noise. MRS parameters were analyzed in relation to histological subtype and grade, surgicopathological staging parameters, MRI-measured tumor volume, and tumor apparent diffusion coefficient (ADC) value and clinical outcome. Results Tumor tissue had significantly higher ratios for tCho/Creatine, tCho/Water, and tCho/Noise than normal myometrial tissue ( P < 0.001 for all). High tumor tCho/Water ratio was significantly associated with high tumor grade in endometrioid tumors ( P = 0.02). Tumor tCho/Creatine ratio was positively correlated to MRI-measured tumor volume (r_s = 0.25; P = 0.03). Conclusion High choline levels in tumor are associated with high-risk features. In vivo MRS may potentially aid in the preoperative risk stratification in endometrial cancer.

Clinicopathologic and molecular markers in cervical carcinoma: a prospective cohort study

BACKGROUND

Cervical cancer is a major health problem worldwide. Identification of effective clinicopathologic and molecular markers is vital to improve treatment stratification.

OBJECTIVES

The purpose of this study was to validate a set of well-defined clinicopathologic features in a large population-based, prospectively collected cervical cancer cohort to support their use in the clinic. Further, we explored p53 and human epidermal growth factor receptor 2 as potential prognostic markers in cervical cancer.

STUDY DESIGN

Tissue was collected from 401 patients with cervical cancer. Clinical data that included follow-up evaluations were collected from patient journals. Histopathologic data were evaluated and revised by an expert pathologist. The prognostic impact of selected clinicopathologic variables was analyzed in the whole cohort. Tissue microarrays were prepared from 292 carcinomas, and p53 and human epidermal growth factor receptor 2 protein levels were evaluated by immunohistochemistry. Fresh frozen samples from overlapping cervical carcinomas previously were subjected to human papilloma virus typing (n=94), whole exome (n=100) and RNA (n=79) sequencing; the results were available for our analyses.

RESULTS

Among the clinicopathologic variables, vascular space invasion, histologic type, and tumor size were verified as strong independent prognostic markers. High p53 protein levels were associated significantly with markers for aggressive phenotype and survival, also in multivariate survival analysis, but did not reflect TP53 mutational status. High human epidermal growth factor receptor 2 protein levels were identified in 21% of all tumors. ERBB2 amplification was associated with poor outcome (P=.003); human epidermal growth factor receptor 2 protein level was not.

CONCLUSIONS

Our findings support that the Féderation Internationale de Gynécologie et d'Obstétrique s guidelines should include vascular space invasion and tumor size 2-4 cm and that careful selection of histologic type is essential for stratification of patient risk groups. High p53 levels independently predict poor survival yet do not reflect mutational status in cervical cancer. Amplified ERBB2 significantly links to poor survival, while HercepTest does not. With optimal stratification, human epidermal growth factor receptor 2-based therapy may improve cervical cancer treatment.

Preoperative imaging markers and PDZ-binding kinase tissue expression predict low-risk disease in endometrial hyperplasias and low grade cancers

PURPOSE

Distinguishing complex atypical hyperplasia (CAH) from grade 1 endometrioid endometrial cancer (EECG1) preoperatively may be valuable in order to prevent surgical overtreatment, particularly in patients wishing preserved fertility or in patients carrying increased risk of perioperative complications.

MATERIAL AND METHODS

Preoperative histological diagnosis and radiological findings were compared to final histological diagnosis in patients diagnosed with CAH and EECG1. Imaging characteristics at preoperative magnetic resonance imaging (MRI) and fluorodeoxyglucose positron emission tomography/computer tomography (FDG-PET/CT) were compared with tumor DNA oligonucleotide microarray data, immunohistochemistry findings and clinicopathological annotations.

RESULTS

MRI assessed tumor volume was higher in EECG1 than in CAH (p=0.004) whereas tumor apparent diffusion coefficient value was lower in EECG1 (p=0.005). EECG1 exhibited increased metabolism with higher maximum and mean standard uptake values (SUV) than CAH (p≤0.002). Unsupervised clustering of EECG1 and CAH revealed differentially expressed genes within the clusters, and identified PDZ-binding kinase (PBK) as a potential marker for selecting endometrial lesions with less aggressive biological behavior.

CONCLUSION

Both PBK expression and preoperative imaging yield promising biomarkers that may aid in the differentiation between EECG1 and CAH preoperatively, and these markers should be further explored in larger patient series.

Late-week surgical treatment of endometrial cancer is associated with worse long-term outcome: Results from a prospective, multicenter study

Surgery is the cornerstone in primary endometrial cancer treatment, and with curative intent it constitutes total hysterectomy and bilateral salpingo-oopherectomy. In addition, lymphadenectomy is performed in selected patients dependent on a preoperative risk assessment. Recent reports from the surgical approach to esophageal cancer reveal worse outcome when esophagectomy is performed later in the week. On this basis, we set out to explore weekday of surgery in relation to long-term outcome in 1302 endometrial cancer patients prospectively included in the MoMaTEC multicenter study. Day of surgery was dichotomized as early-week (Monday-Tuesday) or late-week (Wednesday-Friday), and evaluated as a discrete variable. Adjusted for patient age, Body Mass Index (BMI), FIGO stage, and histology, surgery performed later in the week was associated with 50.9% increased risk of all-cause death (p = 0.029). Among high-stage patients (FIGO stage III and IV), 5-year disease-specific survival proportions were 53.0% for early-week operated vs. 40.2% for late-week operated (p = 0.005 for difference). In multivariate survival analysis of high-stage patients, late-week surgery correlated with an increased risk of disease-specific death by 88.7% and all-cause death by 76.4% (p<0.017). Evaluating only patients who underwent lymphadenectomy, the adverse prognostic effect of being operated late-week remained for both disease-specific and all-cause death (HR 2.151 and HR 1.912, p = 0.004). Whether surgery was performed early- or late-week was not influenced by patient age, BMI, preoperative histology risk classification, FIGO stage or postoperative histology (all p>0.05). In conclusion, endometrial cancer surgery conducted late-week is associated with worse long-term outcome. Our findings are most evident among patients with higher FIGO stages, and patients who underwent more extensive surgical procedure (lymphadenectomy). With support from other studies, our results suggest that high-risk patients may benefit from surgery earlier in the week.

Efficacy of niraparib on progression-free survival (PFS) in patients (pts) with recurrent ovarian cancer (OC) with partial response (PR) to the last platinum-based chemotherapy

5517

Background: Therapeutic paradigms for recurrent OC vary by geography. Maintenance following response to platinum-based chemotherapy (Plat) is standard in Europe, whereas in the US maintenance is considered following complete response (CR) vs treatment for partial response (PR). Niraparib is a highly selective PARP 1/2 inhibitor (PARPi). In preclinical studies it concentrates in the tumor relative to plasma, delivering > 90% durable PARP inhibition and antitumor effects. Niraparib demonstrated significantly longer PFS vs placebo (P) in pts with recurrent OC following a CR or PR to Plat in the randomized, controlled, double-blind phase 3 ENGOT-OV16/NOVA trial. Methods: Pts with recurrent OC, no prior PARPi use, ≥2 prior courses of Plat, and response to most recent Plat were eligible. Pts were assigned to 1 of 2 cohorts on the basis of g BRCA testing (g BRCAmut or non-g BRCAmut) and randomized 2:1 within each cohort to niraparib 300 mg or P qd until progressive disease (PD). Randomization occurred up to 8 weeks after last dose of the most recent Plat. Pts were stratified by time to progression after penultimate Plat (6 to < 12 months or ≥12 months), prior use of bevacizumab (yes/no), and response to most recent Plat (CR or PR). PFS was measured from time of randomization to death or earliest PD as assessed by independent review committee. Results: 49% of pts (niraparib: 67/138; P: 32/65) in the g BRCAmut and ~49% of pts (niraparib: 117/234 [50%]; P: 56/116 [48%]) in the non-g BRCAmut cohorts entered NOVA with a PR following their most recent Plat. At time of unblinding, 30 (45%) niraparib and 23 (72%) P pts in the g BRCAmut and 65 (56%) niraparib and 45 (80%) P pts in the non-g BRCAmut cohorts had PFS events. PFS hazard ratios (95% CI) were 0.24 (0.131–0.441) in g BRCAmut and 0.35 (0.230–0.532) in non-g BRCAmut cohorts for pts who had a PR to their most recent platinum regimen. This compared favorably to the overall NOVA study results, where PFS hazard ratios (95% CI) were 0.27 (0.173–0.410) in g BRCAmut and 0.45 (0.338–0.607) in non-g BRCAmut cohorts. Conclusions: Niraparib treatment provided significant benefit to pts with recurrent OC who achieved a PR following Plat. Clinical trial information: NCT01847274.

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.

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.

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.

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.

Abstract 4692: Relationships between somatic genomic alterations, tumor stage and progression-free survival in cervical cancer

Background:

Cervical cancer is a major public health problem worldwide. We have recently identified novel significantly recurrent somatic mutations in HLA-B, ERBB2 and MAPK1 in cervical squamous cell carcinomas. However, the significance of somatic mutations and copy number alterations for clinical phenotype in cervical cancer is not well understood. This study seeks to identify relationships between somatic genomic alterations, epidemiological exposures, tumor stage (FIGO) and progression-free survival in cervical carcinomas.

Methods:

Cervical tumors were surgically resected or biopsied from 100 Norwegian women with tumor stages I - IV. Patients were subsequently followed for 0-109 months (mean=25 months). Whole exome sequencing (WES) was performed on DNA extracted from tumors and corresponding normal blood. Somatic single nucleotide variants and small insertion/deletions were identified by the MuTect and Indelocator algorithms respectively. The ABSOLUTE algorithm was used to classify mutations as clonal or subclonal. Somatic copy number (CN) data were derived from WES data using the CapSeg algorithm, and significantly recurrent CN alterations were identified by GISTIC2.0 analysis (q&lt;0.25). HPV typing was done by the multiplex fluorescent f-HPV DNA and MassARRAY assays. The log-rank test was used to compare survival curves.

Results:

Non-localized tumors (FIGO stages ≥ II) were associated with focal amplification of the FGFR2 gene on chromosomal cytoband 10q26 (GISTIC q = 0.18531). Indeed, 6 of 8 (75%) tumors with FGFR2 amplification were non-localized, in contrast to 16 of 92 (17%) tumors without FGFR2 amplification (p = 0.001). In addition, patients with somatic ERBB2 mutations and/or amplifications (p = 0.04), somatic TP53 mutations and/or deletions (p = 0.04), or infection with multiple HPV types (p = 0.02) had poorer prognosis (progression-free survival). We also observed a trend for higher frequency of subclonal driver events in patients with poorer survival (p = 0.07).

Conclusion:

We have identified novel relationships between somatic genomic alterations, tumor stage and patient prognosis in cervical cancer. Our data suggest a potential for exploring FGFR2 inhibition in non-localized cervical carcinomas with FGFR2 alterations in a clinical trial context.

Citation Format: Akinyemi I. Ojesina, Bradley Murray, Line Bjorge, Kathrine Woie, Camilla Krakstad, Lee Lichtenstein, Chandra Sekhar Pedamallu, Amaro Taylor-Weiner, Samuel S. Freeman, Andrew D. Cherniack, Michael S. Lawrence, Kristian Cibulskis, Scott L. Carter, Heather Walline, Thomas E. Carey, Olav K. Vintermyr, Bjorn Bertelsen, Christopher P. Crum, Gad Getz, Matthew Meyerson, Helga B. Salvesen. Relationships between somatic genomic alterations, tumor stage and progression-free survival in cervical cancer. [abstract]. In: Proceedings of the 105th Annual Meeting of the American Association for Cancer Research; 2014 Apr 5-9; San Diego, CA. Philadelphia (PA): AACR; Cancer Res 2014;74(19 Suppl):Abstract nr 4692. doi:10.1158/1538-7445.AM2014-4692

Quantification of the concentration gradient of biomarkers between ovarian carcinoma interstitial fluid and blood

Background

Tumor interstitial fluid (TIF) rather than plasma should be used in cancer biomarker discovery because of the anticipated higher concentration of locally produced proteins in the tumor microenvironment. Nevertheless, the actual TIF-to-plasma gradient of tumor specific proteins has not been quantified. We present the proof-of-concept for the quantification of the postulated gradient between TIF and plasma.

Methods

TIF was collected by centrifugation from serous (n = 19), endometrioid (n = 9) and clear cell (n = 3) ovarian carcinomas with early (n = 15) and late stage (n = 16) disease in grades 1 (n = 2), 2 (n = 8) and 3 (n = 17), and ELISA was used for the determination of CA-125, osteopontin and VEGF-A.

Results

All three markers were significantly up-regulated in TIF compared with plasma (p < 0.0001). The TIF-to-plasma ratio of the ovarian cancer biomarker CA-125 ranged from 1.4 to 24,300 (median = 194) and was inversely correlated to stage (p = 0.0006). The cancer related osteopontin and VEGF-A had TIF-to-plasma ratios ranging from 1 to 62 (median = 15) and 2 to 1040 (median = 59), respectively. The ratios were not affected by tumor stage, indicative of more widespread protein expression.

Conclusion

We present absolute quantitative data on the TIF-to-plasma gradient of selected proteins in the tumor microenvironment, and demonstrate a substantial and stage dependent gradient for CA-125 between TIF and plasma, suggesting a relation between total tumor burden and tissue-to-plasma gradient.

General significance

We present novel quantitative data on biomarker concentration in the tumor microenvironment, and a new strategy for biomarker selection, applicable in future biomarker studies.

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Quantification of CA-125, VEGF and osteopontin in tumor interstitial fluid (TIF)

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A large TIF-to-plasma gradient was observed for CA-125, the highest in early stage.

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Lower VEGF and osteopontin gradient indicate more widespread protein expression.

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.

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.

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 sample's 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 1.51. 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 surgeon's experience. Patient satisfaction was high.

Lowering of interstitial fluid pressure after neurogenic inflammation is inhibited by mystixin-7 peptide

Soft tissue injury is accompanied by lowering of interstitial fluid pressure (P(if)), plasma protein extravasation, and edema. Inflammation was produced by electrical stimulation (ES) of the vagus and the effects of the synthetic peptide mystixin-7 (p-anisoyl-Arg-Lys-Leu-Leu-D-Thi-Ile-D-Leu-NH(2)) on P(if) were examined. Micropuncture measurement of P(if) in submucosa, without opening the trachea, was conducted on rats anesthetized with pentobarbital sodium (50 mg/kg) and euthanized with intravenous KCl. P(if) in control (intravenous saline) was -1.2 +/- 0.7 mmHg before ES and decreased to -4.7 +/- 1.0 mmHg (P < 0.01, n = 8) after ES. Mystixin-7 (10 and 20 microg/kg iv) blocked the fall in P(if) after ES (-1.1 +/- 0.3 and -0.8 +/- 0.2 mmHg, P < 0.01, n = 8 and n = 4). The 1 microg/kg dose was without effect. When trachea from animals pretreated with mystixin-7 (20 microg/kg iv) were soaked in phosphate-buffered saline (0.15 M, pH 7.4), the rate of fluid accumulation was significantly reduced. This study suggests that mystixin peptides, which have structural similarity to a fragment from laminin-alpha1 chain, may be useful tools for studying cell adhesion and factors that maintain the structural integrity of connective tissue after injury.

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.

CGRP, but not substance P, induces an increased negativity of the interstitial fluid pressure in rat trachea

Neurogenic inflammation is mediated by neuropeptides released from sensory nerves following electrical stimulation of the vagal nerve or by capsaicin. The released neuropeptides are, among others, calcitonin gene-related peptide and substance P, which both induce vasodilation, while only substance P induces plasma extravasation. Electrical stimulation of the vagal nerve induces increased negativity of interstitial fluid pressure (Pif), which will contribute to enhance oedema formation. Pif was measured, on the abluminal side of the surgically exposed trachea, with sharpened glass capillaries (4-10 microns) connected to a servo-controlled counterpressure system. Measurements were performed after circulatory arrest, since the oedema formation associated with acute inflammation will increase Pif in a positive direction, which may potentially underestimate the increased negativity of Pif. Experiments were carried out in pentobarbital anaesthetized (50 mg kg-1) Wistar-Møller rats. Pif in control rats averaged -1.2 +/- 0.9 (SD) mmHg (n = 9). Intravenous injection of capsaicin (65.0 nmol) and calcitonin gene-related peptide (1.3 nmol) increased the negativity of Pif to -4.0 +/- 1.2 mmHg (n = 8) (P < 0.01) and -4.7 +/- 2.0 mmHg (n = 9) (P < 0.01), respectively. Intravenous injection of substance P (7.4 nmol, n = 9; and 37.0 nmol, n = 8) did not affect Pif compared to control (P > 0.05). Similarly, potentiation of the available substance P with thiorphan or captopril did not increase the negative Pif, nor did injection of stable substance P analogues. Thus, the present study seems to support the theory that, in rat trachea, the increased negativity of Pif after intravenous injection of capsaicin and after vagal stimulation is caused by calcitonin gene-related peptide.

Alloxan diabetes abolishes the increased negativity of interstitial fluid pressure in rat trachea induced by vagal nerve stimulation

Increased negativity of interstitial fluid pressure (Pif) occurs concomitantly with oedema formation in acute airway inflammation. This observation is principally important because the loose connective tissues become 'active' and provide the driving force for the rapid oedema formation via Pif. The present study reports Pif in acute airway inflammation in alloxan diabetic rats. The basis for the study was, firstly, that inflammation is important in the pathogenesis of asthma. Secondly, that clinically there is almost a mutual exclusion between diabetes and asthma and, lastly, that the inflammatory response is attenuated in alloxan diabetic rats. Pif was measured on the ventral side of the trachea with sharpened glass capillaries (3-6 microns) connected to a servocontrolled counterpressure system. Measurements and nerve stimulation were performed after circulatory arrest, since oedema formation associated with inflammation will increase Pif, causing an underestimation of a potentially increased negativity of Pif. Control or diabetic rats (alloxan 45 mg kg-1 i.v. 5 days earlier) received either the mast cell degranulating substance compound 48/80 (100 micrograms), dextran 70 (60 mg) i.v. or vagal nerve stimulation. After dextran, Pif was -4.7 +/- 0.9 (SD) mmHg (n = 6) and -1.3 +/- 0.3 mmHg (n = 6) (P < 0.01) in normal and diabetic rats, respectively. Corresponding values after vagal nerve stimulation were -5.3 +/- 1.8 mmHg (n = 5) and -0.7 +/- 0.2 mmHg (P < 0.01). Insulin treatment restored the Pif response to dextran and vagal stimulation. Pif after Compound 48/80 did not differ between control and diabetic rats. Interstitial volume, total tissue water and transcapillary albumin extravasation increased significantly in controls after vagal nerve stimulation, but was attenuated in diabetic rats.

Integrins and Control of Interstitial Fluid Pressure

The present review summarizes recent information on the physiology of connective tissues, in particular, control of interstitial fluid pressure (Pif) and, thereby, interstitial volume. A combination of classic physiological techniques and techniques from cellular and molecular biology have provided new insights into control of Pif by connective tissue cells and the adhesion receptors anchoring them to structural connective tissue components.

Lowering of interstitial fluid pressure will enhance edema in trachea of albumin-sensitized rats

Interstitial fluid pressure (Pif) has recently been found to play an important role in edema formation in acute airway inflammation. Because airway inflammation is important in the pathogenesis of asthma, Pif was measured in rat trachea after albumin challenge to rats previously sensitized to chicken egg albumin. In pentobarbital anesthesia (50 mg/kg intraperitoneally) sensitized rats received an intravenous infusion of either saline or albumin, which circulated for 4 min. Circulatory arrest was then induced with saturated KCl intravenously to prevent further edema formation, which will increase Pif and thereby possibly cause an underestimation of an increased negativity of Pif. Pif was measured with sharpened glass capillaries (diameter 3-6 micrometer) connected to a servo-controlled counter pressure system. Pif was -1.3 +/- 0.4 mm Hg in controls and -5.8 +/- 0.5 mm Hg in sensitized rats (p < 0.01) after allergen challenge. Airway resistance was measured to verify the occurrence of airway narrowing and increased significantly in sensitized rats after allergen challenge but did not change in controls. The experimental anti-inflammatory drug, alpha-trinositol (D-myo-inositol-1,2,6-trisphosphate, 10 mg), given before or after allergen challenge abolished the increased negativity of Pif (p < 0.05), while hydrocortisone (6.25 mg) had no effect. Thus, allergen challenge is associated with a lowering of Pif, which was abolished by alpha-trinositol.

The relationship between interstitial fluid pressure and volume in rat trachea

A change of interstitial fluid volume (IFV) will normally change the interstitial fluid pressure (Pif) so as to counteract further fluid movement across the capillaries and changes in IFV. Contrary to this, several acute inflammatory reactions in the trachea are associated with increased negativity of Pif, which will 'actively' generate oedema. To outline further the role of Pif in interstitial fluid balance in the trachea, interstitial compliance (delta IFV/delta Pif) was measured in pentobarbital anaesthetized rats. IFV was measured as the plasma equivalent extravascular distribution space of [51Cr]EDTA. Pif was measured in the same animal with sharpened glass pipettes (diameter 3-6 microns) connected to a servocontrolled counterpressure system. In dehydration (30 mL saline i.v., n = 10) interstitial compliance was 0.083 mL g dry wt-1 mmHg-1. Since control IFV was 1.046 mL g dry wt-1 (n = 10) the interstitial compliance is 8% of IFV per mmHg. In overhydration (30 mL NaCl, n = 10) and dextran anaphylaxis (1 mL dextran 70, n = 10) compliance remained the same for the first 15% increase in IFV and then increased several-fold since Pif did not increase more than 2 mmHg above control level. The increased negativity of Pif by -10 mmHg associated with acute inflammation will require a reduction of IFV by 80% when interstitial compliance is 8% per mmHg. A more likely explanation is therefore that structural rearrangements are responsible for the events leading to increased negativity of Pif in acute inflammation.

Neurogenic inflammation and lowering of interstitial fluid pressure in rat trachea is inhibited by alpha-trinositol

The effect of alpha-trinositol (D-myoinositol-1,2,6-triphosphate) on edema formation and capillary permeability in neurogenically induced inflammatory edema was investigated in rat trachea. Interstitial fluid pressure (Pif) was studied, since increased negativity of Pif contributes to edema formation in this situation. alpha-Trinositol was used because it inhibits edema formation, capillary leakage, and increased negativity of Pif in burn-injured skin. Pif was measured with sharpened glass capillaries (3 to 7 microns) connected to a servocontrolled counterpressure system after circulatory arrest (induced by intracardiac injection of saturated potassium chloride in pentobarbital anesthesia). This was done in order to avoid the edema formation associated with inflammatory reactions, which will raise interstitial fluid volume and Pif, causing the underestimation of an increased negativity of Pif. Neurogenic inflammation induced by electrical-field stimulation of the left vagal nerve (10 V, 20 Hz, 0.5 ms) lowered Pif from -1.4 +/- 0.6 mm Hg to -8.4 +/- 2.1 mm Hg (p < 0.01). Corresponding numbers after the intravenous administration of alpha-trinositol (40 mg/kg) before stimulation were -1.2 +/- 0.4 and -1.4 +/- 0.4 mm Hg, respectively (p > 0.05). Another series of animals with intact circulation was used to study the effect of vagal nerve stimulation and alpha-trinositol on edema formation (total tissue water and extravascular 51Cr-ethylenediamine tetraacetic acid-[EDTA] space) and albumin extravasation. These parameters increased significantly after vagal nerve stimulation, while intravenous alpha-trinositol (40 and 120 mg/kg), as given above, significantly attenuated this increase. Thus, alpha-trinositol prevented a lowering of Pif and the edema formation accompanying neurogenic inflammation in rat trachea.

Neurogenic inflammation in rat trachea is accompanied by increased negativity of interstitial fluid pressure

The present experiments were performed to investigate whether neurogenic inflammation in rat trachea (with edema formation and protein extravasation when the circulation is intact) induced by electrical field stimulation of neuropeptide-containing C fibers in the vagal nerve is accompanied by increased negativity of interstitial fluid pressure (P(if)). Increased negativity of P(if) in the trachea occurs in dextran anaphylaxis and mast cell degranulation and facilitates edema formation under these circumstances. Experiments were performed after circulatory arrest had been induced in pentobarbital anesthesia to prevent edema formation, which will raise P(if) and potentially cause underestimation of an increased negativity of P(if). After induction of circulatory arrest, the vagal nerve was isolated and placed in a stimulating electrode. The trachea was then exposed and covered with mineral oil, and measurement of P(if) was started as soon as possible thereafter. P(if) was measured with sharpened glass capillaries (tip diameter, 3 to 7 microns) connected to a servocontrolled counterpressure system. P(if) in the control group (n = 12) did not change throughout the observation period. Electrical stimulation of the left vagal nerve caused P(if) to fall in all experiments, from -1.1 +/- 1.1 mm Hg in the control condition to an average of -10.6 +/- 3.4 mm Hg (n = 9, P < .01). In some experiments, a continuous recording of P(if) was obtained, showing that the reduction of P(if) started within 30 seconds after onset of stimulation to reach and later remain at a stable level within a few minutes. The experimental protocol was repeated after the C fibers had been nearly depleted of neuropeptides with capsaicin.(ABSTRACT TRUNCATED AT 250 WORDS)

Increased negativity of interstitial fluid pressure in rat trachea after mast cell degranulation

The present study was performed to investigate whether the increased negativity of interstitial fluid pressure (Pif) observed after intravenous injection of dextran could be mediated via mast cell degranulation induced by C48/80 and polymyxin B sulfate. Increased negativity of Pif, concomitant with edema formation and increased albumin extravasation, was seen with both substances. However, the two substances differed in that polymyxin B sulfate induced less negativity in Pif and a larger but transient increase in capillary albumin extravasation and interstitial fluid volume. Total tissue water (TTW) increased from 2.11 to 2.71 ml/g dry wt 10 min after polymyxin B and returned to control level at 30 and 60 min. Injection of C48/80 increased TTW to 2.68 ml/g dry wt at 30 min, and TTW was still elevated at 60 min. Albumin extravasation followed a similar pattern; polymyxin B sulfate increased albumin extravasation from < 0.08 to 1.18 ml/g dry wt during the first 5 min after administration. C48/80 was less potent, and maximal albumin leakage was seen after 10-25 min (0.25 ml/g dry wt). The observations demonstrate the importance of the interstitium and the loose connective tissues as "active" participants in the edema-generating process and suggest an interaction with the structural components of the interstitium, as well as an important role for the mast cells in the chain of events creating increased negativity of Pif.