Improved outcomes due to changes in organization of care for patients with ovarian cancer in the Netherlands

OBJECTIVES

Objectives of this study were to evaluate the effect of changes in patterns of care, for example centralization and treatment sequence, on surgical outcome and survival in patients with epithelial ovarian cancer (EOC).

METHODS

Patients diagnosed with FIGO stage IIB-IV EOC (2004-2013) were selected from the Netherlands Cancer Registry. Primary outcomes were surgical outcome (extent of macroscopic residual tumor after surgery) and overall survival. Changes in treatment sequence (primary debulking surgery and adjuvant chemotherapy (PDS+ACT) or neo-adjuvant chemotherapy and interval debulking surgery (NACT+IDS)), hospital type and annual hospital volume were also evaluated.

RESULTS

Patient and tumor characteristics of 7987 patients were retrieved. Most patients were diagnosed with stage III-IV EOC. The average annual case-load per hospital increased from 8 to 28. More patients received an optimal cytoreduction (tumor residue≤1cm) in 2013 (87%) compared to 2004 (55%, p<0.001). Complete cytoreduction (no macroscopic residual tumor), registered since 2010, increased from 42% to 52% (2010 and 2013, respectively, p<0.001). Optimal/complete cytoreduction was achieved in 85% in high volume (≥20 cytoreductive surgeries annually), 80% in medium (10-19 surgeries) and 71% in small hospitals (<10 surgeries, p<0.001). Within a selection of patients with advanced stage disease that underwent surgery the proportion of patients undergoing NACT+IDS increased from 28% (2004) to 71% (2013). Between 2004 and 2013 a 3% annual reduction in risk of death was observed (HR 0.97, p<0.001).

CONCLUSION

Changes in pattern of care for patients with EOC in the Netherlands have led to improvement in surgical outcome and survival.

Improved Risk Assessment by Integrating Molecular and Clinicopathological Factors in Early-stage Endometrial Cancer-Combined Analysis of the PORTEC Cohorts

PURPOSE

Recommendations for adjuvant treatment for women with early-stage endometrial carcinoma are based on clinicopathologic features. Comprehensive genomic characterization defined four subgroups: p53-mutant, microsatellite instability (MSI), POLE-mutant, and no specific molecular profile (NSMP). We aimed to confirm the prognostic capacity of these subgroups in large randomized trial populations, investigate potential other prognostic classifiers, and integrate these into an integrated molecular risk assessment guiding adjuvant therapy.

EXPERIMENTAL DESIGN

Analysis of MSI, hotspot mutations in 14 genes including POLE, protein expression of p53, ARID1a, β-catenin, L1CAM, PTEN, ER, and PR was undertaken on 947 available early-stage endometrioid endometrial carcinomas from the PORTEC-1 and -2 trials, mostly high-intermediate risk (n = 614). Prognostic value was determined using univariable and multivariable Cox proportional hazard models. AUCs of different risk stratification models were compared.

RESULTS

Molecular analyses were feasible in >96% of the patients and confirmed the four molecular subgroups: p53-mutant (9%), MSI (26%), POLE-mutant (6%), and NSMP (59%). Integration of prognostic molecular alterations with established clinicopathologic factors resulted in a stronger model with improved risk prognostication. Approximately 15% of high-intermediate risk patients had unfavorable features (substantial lymphovascular space invasion, p53-mutant, and/or >10% L1CAM), 50% favorable features (POLE-mutant, NSMP being microsatellite stable, and CTNNB1 wild-type), and 35% intermediate features (MSI or CTNNB1-mutant).

CONCLUSIONS

Integrating clinicopathologic and molecular factors improves the risk assessment of patients with early-stage endometrial carcinoma. Assessment of this integrated risk profile is feasible in daily practice, and holds promise to reduce both overtreatment and undertreatment. Clin Cancer Res; 22(16); 4215-24. ©2016 AACR.

TOPical Imiquimod treatment of high-grade Cervical intraepithelial neoplasia (TOPIC trial): study protocol for a randomized controlled trial

Background

Cervical intraepithelial neoplasia (CIN) is the premalignant condition of cervical cancer. Whereas not all high grade CIN lesions progress to cervical cancer, the natural history and risk of progression of individual lesions remain unpredictable. Therefore, high-grade CIN is currently treated by surgical excision: large loop excision of the transformation zone (LLETZ). This procedure has potential complications, such as acute haemorrhage, prolonged bleeding, infection and preterm birth in subsequent pregnancies. These complications could be prevented by development of a non-invasive treatment modality, such as topical imiquimod treatment.

The primary study objective is to investigate the efficacy of topical imiquimod 5 % cream for the treatment of high-grade CIN and to develop a biomarker profile to predict clinical response to imiquimod treatment. Secondary study objectives are to assess treatment side-effects, disease recurrence and quality of life during and after different treatment modalities.

Methods/design

The study design is a randomized controlled trial. One hundred forty women with a histological diagnosis of high-grade CIN (CIN 2–3) will be randomized into two arms: imiquimod treatment during 16 weeks (experimental arm) or immediate LLETZ (standard care arm). Treatment efficacy will be evaluated by colposcopy with diagnostic biopsies at 20 weeks for the experimental arm. Successful imiquimod treatment is defined as regression to CIN 1 or less, successful LLETZ treatment is defined as PAP 1 after 6 months. Disease recurrence will be evaluated by cytology at 6, 12 and 24 months after treatment. Side-effects will be evaluated using a standardized report form. Quality of life will be evaluated using validated questionnaires at baseline, 20 weeks and 1 year after treatment. Biomarkers, reflecting both host and viral factors in the pathophysiology of CIN, will be tested at baseline with the aim of developing a predictive biomarker profile for the clinical response to imiquimod treatment.

Discussion

Treatment of high-grade CIN lesions with imiquimod in a selected patient population may diminish complications as a result of surgical intervention. More knowledge on treatment efficacy, side effects and long-term recurrence rates after treatment is necessary.

Trial registration

EU Clinical Trials Register EU-CTR2013-001260-34. Registered 18 March 2013.

Medical Ethical Committee approval number: NL44336.068.13 (Medical Ethical Committee Maastricht University Hospital, University of Maastricht).

Affiliation: Maastricht University Hospital.

Registration number ClinicalTrials.gov: NCT02329171.

Prognostic significance of L1CAM expression and its association with mutant p53 expression in high-risk endometrial cancer

Studies in early-stage, predominantly low- and intermediate-risk endometrial cancer have demonstrated that L1 cell adhesion molecule (L1CAM) overexpression identifies patients at increased risk of recurrence, yet its prognostic significance in high-risk endometrial cancer is unclear. To evaluate this, its frequency, and the relationship of L1CAM with the established endometrial cancer biomarker p53, we analyzed the expression of both markers by immunohistochemistry in a pilot series of 116 endometrial cancers (86 endometrioid, 30 non-endometrioid subtype) with high-risk features (such as high tumor grade and deep myometrial invasion) and correlated results with clinical outcome. We used The Cancer Genome Atlas (TCGA) endometrial cancer series to validate our findings. Using the previously reported cutoff of 10% positive staining, 51/116 (44%) tumors were classified as L1CAM-positive, with no significant association between L1CAM positivity and the rate of distant metastasis (P=0.195). However, increasing the threshold for L1CAM positivity to 50% resulted in a reduction of the frequency of L1CAM-positive tumors to 24% (28/116), and a significant association with the rate of distant metastasis (P=0.018). L1CAM expression was strongly associated with mutant p53 in the high-risk and TCGA series (P<0.001), although a substantial fraction (36% of endometrioid, 10% of non-endometrioid morphology) of p53-mutant endometrial cancers displayed <10% L1CAM positivity. Moreover, 30% of p53-wild-type non-endometrioid endometrial cancers demonstrated diffuse L1CAM staining, suggesting p53-independent mechanisms of L1CAM overexpression. In conclusion, the previously proposed threshold for L1CAM positivity of >10% does not predict prognosis in high-risk endometrial cancer, whereas an alternative threshold (>50%) does. L1CAM expression is strongly, but not universally, associated with mutant p53, and may be strong enough for clinical implementation as prognostic marker in combination with p53. The high frequency of L1CAM expression in high-risk endometrial cancers suggests that it may also be a promising therapeutic target in this tumor subset.

Vaccination against Oncoproteins of HPV16 for Noninvasive Vulvar/Vaginal Lesions: Lesion Clearance Is Related to the Strength of the T-Cell Response

PURPOSE

Therapeutic vaccination with human papillomavirus type 16 (HPV16) E6 and E7 synthetic long peptides (SLP) is effective against HPV16-induced high-grade vulvar and vaginal intraepithelial neoplasia (VIN/VaIN). However, clinical nonresponders displayed weak CD8(+) T-cell reactivity. Here, we studied if imiquimod applied at the vaccine site could improve CD8(+) T-cell reactivity, clinical efficacy, and safety of HPV16-SLP (ISA101).

EXPERIMENTAL DESIGN

A multicenter open-label, randomized controlled trial was conducted in patients with HPV16(+) high-grade VIN/VaIN. Patients received ISA101 vaccination with or without application of 5% imiquimod at the vaccine site. The primary objective was the induction of a directly ex vivo detectable HPV16-specific CD8(+) T-cell response. The secondary objectives were clinical responses (lesion size, histology, and virology) and their relation with the strength of vaccination-induced immune responses.

RESULTS

Forty-three patients were assigned to either ISA101 with imiquimod (n = 21) or ISA101 only (n = 22). Imiquimod did not improve the outcomes of vaccination. However, vaccine-induced clinical responses were observed in 18 of 34 (53%; 95% CI, 35.1-70.2) patients at 3 months and in 15 of 29 (52%; 95% CI, 32.5-70.6) patients, 8 of whom displayed a complete histologic response, at 12 months after the last vaccination. All patients displayed vaccine-induced T-cell responses, which were significantly stronger in patients with complete responses. Importantly, viral clearance occurred in all but one of the patients with complete histologic clearance.

CONCLUSIONS

This new study confirms that clinical efficacy of ISA101 vaccination is related to the strength of vaccine-induced HPV16-specific T-cell immunity and is an effective therapy for HPV16-induced high-grade VIN/VaIN. Clin Cancer Res; 22(10); 2342-50. ©2016 AACRSee related commentary by Karaki et al., p. 2317.

Size matters: Survival benefit conferred by intratumoral T cells is dependent on surgical outcome, treatment sequence and T cell differentiation

Outcome of cytoreductive surgery, treatment sequence and the differentiation status of T cells are key factors to take into account when studying the prognostic value of tumor-infiltrating lymphocytes (TIL) in high grade serous ovarian cancer.

C-type lectin-like molecule-1 (CLL1)-targeted TRAIL augments the tumoricidal activity of granulocytes and potentiates therapeutic antibody-dependent cell-mediated cytotoxicity

The therapeutic effect of anti-cancer monoclonal antibodies stems from their capacity to opsonize targeted cancer cells with subsequent phagocytic removal, induction of antibody-dependent cell-mediated cytotoxicity (ADCC) or induction of complement-mediated cytotoxicity (CDC). The major immune effector cells involved in these processes are natural killer (NK) cells and granulocytes. The latter and most prevalent blood cell population contributes to phagocytosis, but is not effective in inducing ADCC. Here, we report that targeted delivery of the tumoricidal protein tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) to granulocyte marker C-type lectin-like molecule-1 (CLL1), using fusion protein CLL1:TRAIL, equips granulocytes with high levels of TRAIL. Upon CLL1-selective binding of this fusion protein, granulocytes acquire additional TRAIL-mediated cytotoxic activity that, importantly, potentiates antibody-mediated cytotoxicity of clinically used therapeutic antibodies (e.g., rituximab, cetuximab). Thus, CLL1:TRAIL could be used as an adjuvant to optimize the clinical potential of anticancer antibody therapy by augmenting tumoricidal activity of granulocytes.

Treatment Regimen, Surgical Outcome, and T-cell Differentiation Influence Prognostic Benefit of Tumor-Infiltrating Lymphocytes in High-Grade Serous Ovarian Cancer

PURPOSE

Tumor-infiltrating lymphocytes (TIL) are associated with a better prognosis in high-grade serous ovarian cancer (HGSC). However, it is largely unknown how this prognostic benefit of TIL relates to current standard treatment of surgical resection and (neo-)adjuvant chemotherapy. To address this outstanding issue, we compared TIL infiltration in a unique cohort of patients with advanced-stage HGSC primarily treated with either surgery or neoadjuvant chemotherapy.

EXPERIMENTAL DESIGN

Tissue microarray slides containing samples of 171 patients were analyzed for CD8(+) TIL by IHC. Freshly isolated CD8(+) TIL subsets were characterized by flow cytometry based on differentiation, activation, and exhaustion markers. Relevant T-cell subsets (CD27(+)) were validated using IHC and immunofluorescence.

RESULTS

A prognostic benefit for patients with high intratumoral CD8(+) TIL was observed if primary surgery had resulted in a complete cytoreduction (no residual tissue). By contrast, optimal (<1 cm of residual tumor) or incomplete cytoreduction fully abrogated the prognostic effect of CD8(+) TIL. Subsequent analysis of primary TIL by flow cytometry and immunofluorescence identified CD27 as a key marker for a less-differentiated, yet antigen-experienced and potentially tumor-reactive CD8(+) TIL subset. In line with this, CD27(+) TIL were associated with an improved prognosis even in incompletely cytoreduced patients. Neither CD8(+) nor CD27(+) cell infiltration was of prognostic benefit in patients treated with neoadjuvant chemotherapy.

CONCLUSIONS

Our findings indicate that treatment regimen, surgical result, and the differentiation of TIL should all be taken into account when studying immune factors in HGSC or, by extension, selecting patients for immunotherapy trials.

Prediction model for regional or distant recurrence in endometrial cancer based on classical pathological and immunological parameters

BACKGROUND

Adjuvant therapy increases disease-free survival in endometrial cancer (EC), but has no impact on overall survival and negatively influences the quality of life. We investigated the discriminatory power of classical and immunological predictors of recurrence in a cohort of EC patients and confirmed the findings in an independent validation cohort.

METHODS

We reanalysed the data from 355 EC patients and tested our findings in an independent validation cohort of 72 patients with EC. Predictors were selected and Harrell's C-index for concordance was used to determine discriminatory power for disease-free survival in the total group and stratified for histological subtype.

RESULTS

Predictors for recurrence were FIGO stage, lymphovascular space invasion and numbers of cytotoxic and memory T-cells. For high risk cancer, cytotoxic or memory T-cells predicted recurrence as well as a combination of FIGO stage and lymphovascular space invasion (C-index 0.67 and 0.71 vs 0.70). Recurrence was best predicted when FIGO stage, lymphovascular space invasion and numbers of cytotoxic cells were used in combination (C-index 0.82). Findings were confirmed in the validation cohort.

CONCLUSIONS

In high-risk EC, clinicopathological or immunological variables can predict regional or distant recurrence with equal accuracy, but the use of these variables in combination is more powerful.

Abstract 1537: Tumor stroma in serous ovarian cancer; inter and intra patient heterogeneity and impact on survival

Purpose of the study: This study subjected primary tumors and matched metastasis of serous ovarian cancer to a multi-parametric analysis of tumor stroma characteristics. The aims were to explore potential co-regulation of these characteristics, analyze their concordance in primary and metastatic lesions and define their correlation to survival. The impact of tumor microenvironment in serous ovarian cancer is largely unexplored and new prognostic tools for this tumor are strongly needed Experimental procedures: A retrospective consecutive study was performed, including 321 patients at primary surgery of ovarian cancer. Patients with serous ovarian cancer (N = 186) were included in the current study, 91 with matched primary and metastatic tissue. A tissue microarray (TMA) was built from the pre-treatment paraffin-embedded samples and was subjected to immunohistochemistry double staining with CD34 (endothelial cell marker) together with the fibroblast and pericyte markers alpha smooth muscle actin (α-SMA), platelet-derived growth factor receptor beta (PDGFβR), and the pericyte marker desmin. The images were digitally analyzed to yield thirteen “tumor-stroma metrics” related to the vasculature and the fibroblast-rich stroma. Spearman two-tails test was used for correlation estimates. Log Rank test and Cox proportional hazards models were used to estimate the overall survival (OS) with uni and multivariate analysis.

Results: Within the ovarian primary site, we found a strong association between expression of PDGFβR in perivascular cells and in fibroblasts. Similar findings were made concerning α-SMA-positive fibroblasts and perivascular cells. Most stroma characteristics except PDGFβR expression in fibroblast stroma and in perivascular cells, showed large variations when matched primary tumors and metastasis were compared. Large PDGFβR-positive stroma fraction, as well as high PDGFβFR positive perivascular intensity, was significantly associated with worse survival in uni and multivariate analysis (HR 1.7, Cl 95% 1.1-2.5 and HR 1.7, Cl 95% 1.1-2.7, respectively).

Conclusions: The study identified previously unrecognized co-regulation patterns of PDGFβR-positive perivascular cells and fibroblasts, and α-SMA-positive perivascular cells and fibroblasts; it revealed that status of stromal markers, except PDGFβR, differs between matched primary tumors and metastases. Moreover analyses identified PDGFβR expression in perivascular cells and in fibroblasts as novel prognosis markers. This prognosis association is in agreement with previous findings from breast and prostate cancer and suggests that PDGFβR could be explored as a target for personalized tumor microenvironment-targeted treatments.

Citation Format: Sara Corvigno, Bea Wisman, Ate G.J. Van der Zee, Hans W. Nijman, Artur Mezheyeuski, Elisabeth Åvall Lundkvist, Arne Östman, Hanna Dahlstrand. Tumor stroma in serous ovarian cancer; inter and intra patient heterogeneity and impact on survival. [abstract]. In: Proceedings of the 106th Annual Meeting of the American Association for Cancer Research; 2015 Apr 18-22; Philadelphia, PA. Philadelphia (PA): AACR; Cancer Res 2015;75(15 Suppl):Abstract nr 1537. doi:10.1158/1538-7445.AM2015-1537

A phase I trial combining carboplatin/doxorubicin with tocilizumab, an anti-IL-6R monoclonal antibody, and interferon-α2b in patients with recurrent epithelial ovarian cancer

BACKGROUND

The immune system is important in epithelial ovarian cancer (EOC). Interleukin-6 is associated with chemoresistance and an immune-suppressive tumor microenvironment. We investigated whether a combination of chemotherapeutics, blockade of interleukin 6 (IL-6) receptor (IL-6R; tocilizumab), and immune enhancer interferon-α (Peg-Intron) is feasible, safe, and able to enhance immunity in patients with recurrent EOC.

PATIENTS AND METHODS

In this dose-escalation study, patients received tocilizumab 1, 2, 4, or 8 mg/kg i.v., q4 weeks during the first three cycles of carboplatin (AUC5) plus doxorubicin [pegylated liposomal doxorubicin (PLD) 30 mg/m(2) or doxorubicin 50 mg/m(2) i.v., day 1, q4 weeks, for six cycles]. At the highest tocilizumab dose (8 mg/kg), Peg-Intron (1 µg/kg s.c.) was added. Peripheral blood mononuclear cells were collected for immunomonitoring at baseline, after three and six cycles. Dose-limiting toxicity (DLT), CA-125, and radiologic response were evaluated.

RESULTS

In the 23 patients enrolled, no DLT was established. The most frequent grade 3/4 adverse events (CTCAE v4.03) were neutropenia (23%), febrile neutropenia (19%), and ileus (19%). No treatment-related deaths occurred. Using CT evaluation, 11 of 21 assessable patients responded, 6 had stable disease and 3 progressive disease. Patients receiving highest dose tocilizumab showed a functional blockade of IL-6R with increased levels of serum IL-6 (P = 0.02) and soluble IL-6R (P = 0.008). Consequently, immune cells displayed decreased levels of pSTAT3, myeloid cells produced more IL-12 and IL-1β while T cells were more activated and secreted higher amounts of effector cytokines interferon-γ and tumor necrosis factor-α. An increase in sIL-6R was potentially associated with a survival benefit (P = 0.03).

CONCLUSIONS

Functional IL-6R blocking is feasible and safe in EOC patients treated with carboplatin/(pegylated liposomal)doxorubicin, using 8 mg/kg tocilizumab. This combination is recommended for phase II evaluation based on immune parameters.

CLINICAL TRIAL REGISTER

NCT01637532.

POLE Proofreading Mutations Elicit an Antitumor Immune Response in Endometrial Cancer

PURPOSE

Recent studies have shown that 7% to 12% of endometrial cancers are ultramutated due to somatic mutation in the proofreading exonuclease domain of the DNA replicase POLE. Interestingly, these tumors have an excellent prognosis. In view of the emerging data linking mutation burden, immune response, and clinical outcome in cancer, we investigated whether POLE-mutant endometrial cancers showed evidence of increased immunogenicity.

EXPERIMENTAL DESIGN

We examined immune infiltration and activation according to tumor POLE proofreading mutation in a molecularly defined endometrial cancer cohort including 47 POLE-mutant tumors. We sought to confirm our results by analysis of RNAseq data from the TCGA endometrial cancer series and used the same series to examine whether differences in immune infiltration could be explained by an enrichment of immunogenic neoepitopes in POLE-mutant endometrial cancers.

RESULTS

Compared with other endometrial cancers, POLE mutants displayed an enhanced cytotoxic T-cell response, evidenced by increased numbers of CD8(+) tumor-infiltrating lymphocytes and CD8A expression, enrichment for a tumor-infiltrating T-cell gene signature, and strong upregulation of the T-cell cytotoxic differentiation and effector markers T-bet, Eomes, IFNG, PRF, and granzyme B. This was accompanied by upregulation of T-cell exhaustion markers, consistent with chronic antigen exposure. In silico analysis confirmed that POLE-mutant cancers are predicted to display more antigenic neoepitopes than other endometrial cancers, providing a potential explanation for our findings.

CONCLUSIONS

Ultramutated POLE proofreading-mutant endometrial cancers are characterized by a robust intratumoral T-cell response, which correlates with, and may be caused by an enrichment of antigenic neopeptides. Our study provides a plausible mechanism for the excellent prognosis of these cancers.

Refining prognosis and identifying targetable pathways for high-risk endometrial cancer; a TransPORTEC initiative

This study aimed to investigate whether molecular analysis can be used to refine risk assessment, direct adjuvant therapy, and identify actionable alterations in high-risk endometrial cancer. TransPORTEC, an international consortium related to the PORTEC3 trial, was established for translational research in high-risk endometrial cancer. In this explorative study, routine molecular analyses were used to detect prognostic subgroups: p53 immunohistochemistry, microsatellite instability and POLE proofreading mutation. Furthermore, DNA was analyzed for hotspot mutations in 13 additional genes (BRAF, CDKNA2, CTNNB1, FBXW7, FGFR2, FGFR3, FOXL2, HRAS, KRAS, NRAS, PIK3CA, PPP2R1A, and PTEN) and protein expression of ER, PR, PTEN, and ARID1a was analyzed. Rates of distant metastasis, recurrence-free, and overall survival were calculated using the Kaplan-Meier method and log-rank test. In total, samples of 116 high-risk endometrial cancer patients were included: 86 endometrioid; 12 serous; and 18 clear cell. For endometrioid, serous, and clear cell cancers, 5-year recurrence-free survival rates were 68%, 27%, and 50% (P=0.014) and distant metastasis rates 23%, 64%, and 50% (P=0.001), respectively. Four prognostic subgroups were identified: (1) a group of p53-mutant tumors; (2) microsatellite instable tumors; (3) POLE proofreading-mutant tumors; and (4) a group with no specific molecular profile (NSMP). In group 3 (POLE-mutant; n=14) and group 2 (microsatellite instable; n=19) patients, no distant metastasis occurred, compared with 50% distant metastasis rate in group 1 (p53-mutant; n=36) and 39% in group 4 (NSMP; P<0.001). Five-year recurrence-free survival was 93% and 95% for group 3 (POLE-mutant) and group 2 (microsatellite instable) vs 42% (group 1, p53-mutant) and 52% (group 4, NSMP; P<0.001). Targetable FBXW7 and FGFR2 mutations (6%), alterations in the PI3K-AKT pathway (60%) and hormone receptor positivity (45%) were frequently found. In conclusion, molecular analysis of high-risk endometrial cancer identifies four distinct prognostic subgroups, with potential therapeutic implications. High frequencies of targetable alterations were identified and may serve as targets for individualized treatment.

A rationally designed combined treatment with an alphavirus-based cancer vaccine, sunitinib and low-dose tumor irradiation completely blocks tumor development

The clinical efficacy of therapeutic cancer vaccines remains limited. For effective immunotherapeutic responses in cancer patients, multimodal approaches capable of both inducing antitumor immune responses and bypassing tumor-mediated immune escape seem essential. Here, we report on a combination therapy comprising sunitinib (40 mg/kg), single low-dose (14 Gy) tumor irradiation and immunization with a therapeutic cancer vaccine based on a Semliki Forest virus vector encoding the oncoproteins E6 and E7 of human papillomavirus (SFVeE6,7). We previously demonstrated that either low-dose irradiation or sunitinib in single combination with SFVeE6,7 immunizations enhanced the intratumoral ratio of antitumor effector cells to myeloid-derived suppressor cells (MDSCs). On the basis of these results we designed a triple treatment combinatorial regimen. The trimodal sunitinib, low-dose irradiation and SFVeE6,7 immunization therapy resulted in stronger intratumoral MDSC depletion than sunitinib alone. Concomitantly, the highest levels of intratumoral E7-specific CD8⁺ T cells were attained after triple treatment. Approximately 75% of these cells were positive for the early activation marker CD69. The combination of sunitinib, low-dose tumor irradiation and SFVeE6,7 immunization dramatically changed the intratumoral immune compartment. Whereas control tumors contained 0.02 E7-specific CD8⁺ T cells per MDSC, triple treatment tumors contained more than 200 E7-specific CD8⁺ T cells per MDSC, a 10,000-fold increased ratio. As a result, the triple treatment strongly enhanced the immunotherapeutic antitumor effect, blocking tumor development altogether and leading to 100% tumor-free survival of tumor-bearing mice. This study demonstrates that this multimodal approach elicits superior antitumor effects and should be considered for clinical applications.

CD20+ T cells have a predominantly Tc1 effector memory phenotype and are expanded in the ascites of patients with ovarian cancer

Recently, a small subset of T cells that expresses the B cell marker CD20 has been identified in healthy volunteers and in patients with rheumatoid arthritis and multiple sclerosis. The origin of these CD20-positive T cells as well as their relevance in human disease remains unclear. Here, we identified that after functional B cell/T cell interaction CD20 molecules are transferred to the cell surface of T cells by trogocytosis together with the established trogocytosis marker HLA-DR. Further, the presence of CD20 on isolated CD20⁺ T cells remained stable for up to 48h of ex vivo culture. These CD20⁺ T cells almost exclusively produced IFNγ (∼70% vs. ∼20% in the CD20^- T cell population) and were predominantly (CD8⁺) effector memory T cells (∼60-70%). This IFNγ producing and effector memory phenotype was also determined for CD20⁺ T cells as detected in the peripheral blood and ascitic fluids of ovarian cancer (OC) patients. In the latter, the percentage of CD20⁺ T cells was further strongly increased (from ∼6% in peripheral blood to 23% in ascitic fluid). Taken together, the data presented here indicate that CD20 is transferred to T cells upon intimate T cell/B cell interaction. Further, CD20⁺ T cells are of memory and IFNγ producing phenotype and are present in increased amounts in ascitic fluid of OC patients.

Indoleamine-2,3-dioxygenase (IDO) metabolic activity is detrimental for cervical cancer patient survival

The expression of the immunomodulating enzyme indoleamine-2,3-dioxygenase (IDO) suppresses T-lymphocyte function, thus correlating with poor survival in a variety of cancer patients. IDO degrades the essential amino acid tryptophan leading to immunosuppressive kynurenines production. In the present study, concentrations of tryptophan, 3-hydroxykynurenine, and kynurenine were measured in pre-treatment serum samples of 251 cervical cancer patients by a mass-spectrometric method (XLC-MS/MS) and IDO activity determined by the kynurenine/tryptophan (Kyn/Trp) ratio. A low concentration of tryptophan was found to be significantly associated with tumors greater than 4 cm and lymph node metastatic spread. Furthermore, significant positive correlations were found between high concentrations of the tryptophan metabolites kynurenine and 3-hydroxykynurenine and advanced disease stage (FIGO >IIA) and lymph node metastases. High levels of kynurenine were further associated with parametrial invasion and tumor size. A high Kyn/Trp ratio was related to lymph node metastasis, FIGO stage, tumor size, parametrial invasion and poor disease-specific survival. These results suggest that IDO activation is linked to poor clinicopathological parameters and worse survival in cervical cancer, warranting the use of IDO inhibitors in future clinical trials.

Natural history of high-grade cervical intraepithelial neoplasia: a review of prognostic biomarkers

The natural history of high-grade cervical intraepithelial neoplasia (CIN) is largely unpredictable and current histopathological examination is unable to differentiate between lesions that will regress and those that will not. Therefore, most high-grade lesions are currently treated by surgical excision, leading to overtreatment and unnecessary complications. Prognostic biomarkers may differentiate between lesions that will regress and those that will not, making individualized treatment of high-grade CIN possible. This review identifies several promising prognostic biomarkers. These biomarkers include viral genotype and viral DNA methylation (viral factors), human leukocyte antigen-subtypes, markers of lymphoproliferative response, telomerase amplification and human papillomavirus-induced epigenetic effects (host factors) and Ki-67, p53 and pRb (cellular factors). All identified biomarkers were evaluated according to their role in the natural history of high-grade CIN and according to established criteria for evaluation of biomarkers (prospective-specimen-collection, retrospective-blinded-evaluation [PROBE] criteria). None of the biomarkers meets the PROBE criteria for clinical applicability and more research on prognostic biomarkers in high-grade CIN is necessary.

Myeloid derived suppressor cells-An overview of combat strategies to increase immunotherapy efficacy

Myeloid-derived suppressor cells (MDSCs) contribute to tumor-mediated immune escape and negatively correlate with overall survival of cancer patients. Nowadays, a variety of methods to target MDSCs are being investigated. Based on the intervention stage of MDSCs, namely development, expansion and activation, function and turnover, these methods can be divided into: (I) prevention or differentiation to mature cells, (II) blockade of MDSC expansion and activation, (III) inhibition of MDSC suppressive activity or (IV) depletion of intratumoral MDSCs. This review describes effective mono- or multimodal-therapies that target MDSCs for the benefit of cancer treatment.

Interleukin-6 receptor and its ligand interleukin-6 are opposite markers for survival and infiltration with mature myeloid cells in ovarian cancer

An increased level of interleukin-6 (IL-6) in epithelial ovarian cancer (EOC) is correlated with a worse prognosis. IL-6 stimulates tumor-growth and inflammation. We investigated the intricate interaction between the IL-6 signaling pathway and tumor-infiltrating myeloid cells (TIMs) to determine their prognostic impact in EOC. 160 EOC samples were analyzed for the expression of IL-6, its receptor (IL-6R) and downstream signaling via pSTAT3 by immunohistochemistry. Triple color immunofluorescence confocal microscopy was used to identify myeloid cell populations by CD14, CD33, and CD163. The relationship between these markers, tumor-infiltrating immune cells, clinical-pathological characteristics and survival was investigated. EOC displayed a dense infiltration with myeloid cells, in particular of the CD163⁺ type. The distribution pattern of all myeloid subtypes was comparable among the different histological subtypes. Analysis of the tumor cells revealed a high expression of IL-6R in 15% and of IL-6 in 23% of patients. Interestingly, tumors expressing IL-6 or IL-6R formed two different groups. Tumors with a high expression of IL-6R displayed low mature myeloid cell infiltration and a longer disease-specific survival (DSS), especially in late stage tumors. High expression of IL-6R was an independent prognostic factor for survival by multivariate analyses (hazard ratio = 0.474, p = 0.011). In contrast, tumors with high epithelial IL-6 expression displayed a dense infiltration of mature myeloid cells and were correlated with a shorter DSS. Furthermore, in densely CD8⁺ T-cell infiltrated tumors, the ratio between these lymphoid cells and CD163⁺ myeloid cells was predictive for survival. Thus, IL-6 and IL-6R are opposite markers for myeloid cell infiltration and survival.

Sunitinib depletes myeloid-derived suppressor cells and synergizes with a cancer vaccine to enhance antigen-specific immune responses and tumor eradication

The high efficacy of therapeutic cancer vaccines in preclinical studies has yet to be fully achieved in clinical trials. Tumor immune suppression is a critical factor that hampers the desired antitumor effect. Here, we analyzed the combined effect of a cancer vaccine and the receptor tyrosine kinase inhibitor sunitinib. Sunitinib was administered intraperitoneally, alone or in combination with intramuscular immunization using a viral vector based cancer vaccine composed of Semliki Forest virus replicon particles and encoding the oncoproteins E6 and E7 (SFVeE6,7) of human papilloma virus (HPV). We first demonstrated that treatment of tumor-bearing mice with sunitinib alone dose-dependently depleted myeloid-derived suppressor cells (MDSCs) in the tumor, spleen and in circulation. Concomitantly, the number of CD8⁺ T cells increased 2-fold and, on the basis of CD69 expression, their activation status was greatly enhanced. The intrinsic immunosuppressive activity of residual MDSCs after sunitinib treatment was not changed in a dose-dependent fashion. We next combined sunitinib treatment with SFVeE6,7 immunization. This combined treatment resulted in a 1.5- and 3-fold increase of E7-specific cytotoxic T lymphocytes (CTLs) present within the circulation and tumor, respectively, as compared to immunization only. The ratio of E7-specific CTLs to MDSCs in blood thereby increased 10- to 20-fold and in tumors up to 12.5-fold. As a result, the combined treatment strongly enhanced the antitumor effect of the cancer vaccine. This study demonstrates that sunitinib creates a favorable microenvironment depleted of MDSCs and acts synergistically with a cancer vaccine resulting in enhanced levels of active tumor-antigen specific CTLs, thus changing the balance in favor of antitumor immunity.

HPV-specific immunotherapy: key role for immunomodulators

Cervical cancer is the second most common malignancy among women worldwide. The prime causal factor of the disease is a persistent infection with human papillomavirus (HPV) with individuals failing to mount a sufficient immune response against the virus. Despite the current success of HPV16- and 18-specific prophylactic vaccination, established HPV infections and associated neoplasia require therapeutic vaccines with the induction of cellular immunity. The sustained expression of early proteins E6 and E7 from major oncogenic HPV genotypes in cervical lesions are ideal targets for the design of immunotherapeutic strategies. These strategies, particularly subunit vaccines, may require additional help from immunomodulators to enhance HPV-specific cellular responses. This review discusses recent studies, published since 2008, relating to immunotherapeutic strategies against HPV that include immunomodulators. These immunomodulators fall within the category of toll-like receptor adjuvants for innate immune activation, adjuvants directly contributing to adaptive immunity, such as cytokines and costimulatory molecules, and those that target tumor-induced immunosuppressive mechanisms. Using a combination of these strategies with delivery-based approaches may be most beneficial for the success of therapeutic vaccines against HPV-induced neoplasia in the clinic.

Molecular profiling of circulating tumor cells links plasticity to the metastatic process in endometrial cancer

BACKGROUND

About 20% of patients diagnosed with endometrial cancer (EC) are considered high-risk with unfavorable prognosis. In the framework of the European Network for Individualized Treatment in EC (ENITEC), we investigated the presence and phenotypic features of Circulating Tumor Cells (CTC) in high-risk EC patients.

METHODS

CTC isolation was carried out in peripheral blood samples from 34 patients, ranging from Grade 3 Stage IB to Stage IV carcinomas and recurrences, and 27 healthy controls using two methodologies. Samples were subjected to EpCAM-based immunoisolation using the CELLection™ Epithelial Enrich kit (Invitrogen, Dynal) followed by RTqPCR analysis. The phenotypic determinants of endometrial CTC in terms of pathogenesis, hormone receptor pathways, stem cell markers and epithelial to mesenchymal transition (EMT) drivers were asked. Kruskal-Wallis analysis followed by Dunn's post-test was used for comparisons between groups. Statistical significance was set at p < 0.05.

RESULTS

EpCAM-based immunoisolation positively detected CTC in high-risk endometrial cancer patients. CTC characterization indicated a remarkable plasticity phenotype defined by the expression of the EMT markers ETV5, NOTCH1, SNAI1, TGFB1, ZEB1 and ZEB2. In addition, the expression of ALDH and CD44 pointed to an association with stemness, while the expression of CTNNB1, STS, GDF15, RELA, RUNX1, BRAF and PIK3CA suggested potential therapeutic targets. We further recapitulated the EMT phenotype found in endometrial CTC through the up-regulation of ETV5 in an EC cell line, and validated in an animal model of systemic dissemination the propensity of these CTC in the accomplishment of metastasis.

CONCLUSIONS

Our results associate the presence of CTC with high-risk EC. Gene-expression profiling characterized a CTC-plasticity phenotype with stemness and EMT features. We finally recapitulated this CTC-phenotype by over-expressing ETV5 in the EC cell line Hec1A and demonstrated an advantage in the promotion of metastasis in an in vivo mouse model of CTC dissemination and homing.