Prevalence of PD-L1 in Cervical Cancer Patients and the Potential for Combining an Immune Checkpoint Inhibitor With Lenvatinib

BACKGROUND/AIM

Cervical cancer is the fourth most common cause of cancer-related deaths in women worldwide. The potential for targeted therapy against the immune checkpoint programmed death 1 (PD-1)/programmed death-ligand 1 (PD-L1) and receptor tyrosine kinases was examined in cervical cancer patients and cell lines.

MATERIALS AND METHODS

On tissue microarrays, PD-L1 was analyzed in 123 samples of patients with cervical cancer using immunohistochemistry. In SiHa, HeLa, and CaSki cervical cancer cell lines we examined the combination of lenvatinib with a PD-1/PD-L1 inhibitor using cell viability assays, the activation of cell signaling pathway proteins using western blots and gene expression using quantitative reverse transcriptase-PCR.

RESULTS

Of 113 evaluable samples, 90 (79.6%) had more than 1% PD-L1 positive cells. The single treatment with the PD-1/PD-L1 inhibitor resulted in the greatest reduction in growth for CaSki and lenvatinib in HeLa cells. In contrast, the combined treatment of lenvatinib with the PD-1/PD-L1 inhibitor demonstrated a significantly stronger impeded proliferation compared to the single treatment in all three cell lines. Moreover, the combined treatment caused significantly less phosphorylation of the signaling molecules ERK and S6 in SiHa and of S6 and STAT3 in HeLa cells but not in CaSki. All treatments diminished the mRNA levels of PD-L1, Il-8, and FGFR in SiHa cells.

CONCLUSION

PD1 is frequently expressed in cervical cancer samples. Combining lenvatinib with a PD-1/PD-L1 inhibitor diminished proliferation of cervical cancer cell lines. Consequently, this combination might be a promising option to treat cervical cancer. Signaling pathways involved in tumor cell growth are blocked by the combined treatment but still a model of the underlying mechanism cannot be drawn.

Overexpression of the orphan nuclear receptor NR2F6 is associated with improved survival across molecular subgroups in endometrial cancer patients

INTRODUCTION

NR2F6 (nuclear receptor subfamily 2 group F member 6, also called Ear-2) is known to be an orphan nuclear receptor that has been characterized as an intracellular immune checkpoint in effector T cells and, therefore, may control tumor development and growth. The prognostic impact of NR2F6 in endometrial cancers is evaluated in this study.

MATERIALS AND METHODS

Expression analysis of NR2F6 in 142 endometrial cancer patients was performed by immunohistochemistry of primary paraffin‑embedded tumor samples. Staining intensity of positive tumor cells was automatically assessed semi-quantitatively, and results were correlated with clinicopathological characteristics and survival.

RESULTS

Forty five of 116 evaluable samples (38.8%) showed an overexpression of NR2F6. This leads to an improvement of the overall survival (OS) and progression-free survival (PFS). In NR2F6-positive patients, the estimated mean OS was 156.9 months (95% confidence interval (CI) 143.1-170.7) compared to 106.2 months in NR2F6-negative patients (95% CI 86.2-126.3; p = 0.022). The estimated PFS differed by 63 months (152 months (95% CI 135.7-168.4) vs. 88.3 months (95% CI 68.5-108.0), p = 0.002). Furthermore, we found significant associations between NR2F6 positivity, MMR status, and PD1 status. A multivariate analysis suggests NR2F6 to be an independent factor influencing the OS (p = 0.03).

CONCLUSION

In this study, we could demonstrate that there is a longer progression-free and overall survival for NR2F6-positive patients with endometrial cancer. We conclude that NR2F6 might play an essential role in endometrial cancers. Further studies are required to validate its prognostic impact.

Distribution of HPV Subtypes in Diverse Anogenital and Oral Samples from Women and Correlation of Infections with Neoplasia of the Cervix

Simple Summary

Human papilloma virus (HPV)-associated cancers and their precursors are increasing worldwide. The purpose of our study was to investigate HPV subtypes in anogenital and oral samples to analyze the distribution and frequency of high- and low-risk HPV in the cervix, vagina, vulva, anus, and oral cavity. Identification of special HPV subtypes for these areas may help to increase the prognostic value of HPV screening for early detection of precursors or cancers being highly HPV-attributable. HPV genotyping with the EUROArray HPV test was performed in 509 patient samples from our dysplasia consultation. In addition to the well described HPV, e.g., HPV 16 and HPV 31, we detected further HPV subtypes with higher incidences in the investigated areas (e.g., HPV 53 and HPV 73) which may be evident for precursors and cancers of all areas.

Abstract

Background: Cancers and intraepithelial lesions of different anogenital areas as well as oral cancer are associated with human papilloma virus (HPV) infections. Methods: In this study cervical, vaginal, vulvar, anal, and oral samples were taken from 509 patients visiting our dysplasia consultation clinic. HPV genotyping was performed using the EUROArray HPV test. Results: Positivity of HR HPV was found in 60.4–64.3% of anogenital and 14.6% of oral samples. HPV 16 showed the highest incidence in all investigated areas. In cervical and vaginal samples HPV 31 was detected second most, while in vulvar, anal, and oral samples HPV 53 was the second most common subtype. HPV 18 was found lower in all areas, while HPV 51, HPV 52, and HPV 73 were detected higher than expected from published data. A good concordance between cervical, vaginal and vulvar samples was examined for most of the HPV. HR HPV infection was higher in cervical cancer (CC; 91.7%) and high-grade intraepithelial squamous lesions (HSIL; 93.9%) compared to low-grade SIL (LSIL; 69.6%) and normal samples (44.8%). Conclusion: In addition to the well described HPV subtypes, we found others with high incidences in the investigated areas which may be evident for HSIL and CC of those areas.

PSMD9 expression correlates with recurrence after radiotherapy in patients with cervical cancer

In the current retrospective cohort study, the expression of the Proteasome 26S non-ATPase Subunit 9 (PSMD9) was investigated in 102 patients with cervical cancer. The rat homologue of PSMD9, Bridge-1, was identified as a binding protein of the transcription factors PDX-1 and E-12 via its PDZ-domain. The aim of the current study was to evaluate the prognostic or predictive value of PSMD9 expression as a biomarker for patients with cervical cancer. Tissue microarrays were constructed from formalin-fixed paraffin-embedded tissue specimens of cervical cancer and peritumoral stroma after hysterectomy and a Bridge-1 antibody was used to perform immunohistochemistry. The immunoreactions were analyzed using an immunoreactive score, which evaluated the number of positive cells as well as their intensity of PSMD9 expression. A misinterpretation of statistically significant results after multiple testing was controlled by the false discovery rate correction using the algorithm of Benjamini and Hochberg. All tumor tissues and almost all peritumoral stroma tissues expressed PSMD9. The PSMD9 expression in tumor tissues was significantly higher compared with the peritumoral stroma. PSMD9 expression correlated significantly with the expression of the proliferation marker MIB-1. Patients with stronger PSMD9 expression tended to exhibit a higher odds ratio for the recurrence of the disease in all patients (n=102) as well as in the subgroup of 47 patients having received a combined chemoradiotherapy following hysterectomy. In the group of 62 patients having that received radiotherapy following hysterectomy, which included the chemoradiotherapy patients, a higher PSMD9 expression significantly increased the odds for a recurrence to 1.983-fold even after FDR correction (P=0.0304). In conclusion, PSMD9 was indicated to be overexpressed in tumor tissues and associated with tumor cell proliferation. Therefore, PSMD9 may be useful as a tumor marker. Furthermore, increased PSMD9 overexpression may be used to predict resistance against radiation.

Effects of Combined Treatment with Vitamin D and COX2 Inhibitors on Breast Cancer Cell Lines

BACKGROUND

Vitamin D is known for its anticancer potential. Prostaglandin E₂ (PGE₂) is a proliferative and inflammation-activating agent. The production of PGE₂ is dependent on the activity of cyclooxygenase-2 (COX2). A link between vitamin D and PGE₂ metabolism was shown recently.

MATERIALS AND METHODS

In MDA-MB-231 and MCF-7 breast cancer cell lines, we investigated the influence of calcitriol and the COX2 inhibitor celecoxib on cell growth via the MTT test, as well as on the protein and mRNA expression of COX2 using western blot and quantitative real-time polymerase chain reaction (qRT-PCR).

RESULTS

The proliferation of MCF-7 and MDA-MB-231 was inhibited by both calcitriol and the COX2 inhibitor celecoxib and even more strongly by their combination. Moreover, calcitriol inhibited COX2 protein expression in MDA-MB-231 cells, as well as COX2 mRNA expression in both cell lines.

CONCLUSION

The combination of calcitriol and celecoxib demonstrated a synergistic growth-inhibitory effect in breast cancer cell lines.

Claudin-1 expression in cervical cancer

Claudin-1 is a tight junction protein that has been demonstrated to be involved in tumorigenesis and tumor progression in various types of solid tumors. In the present study, the protein expression of claudin-1 in squamous cervical cancer tissues obtained from 106 patients was analyzed by immunohistochemistry. In addition, the grade of claudin-1 expression was analyzed for associations with certain clinicopathological parameters. A significant overexpression of claudin-1 was detected in the tumor cells, when compared with that in the peritumoral stroma. There was no significant association between claudin-1 expression and FIGO stage, tumor size, grading or the appearance of distant metastases. Cervical cancer patients scoring positive for claudin-1 protein expression tended to exhibit more lymph node metastasis (28.3%), compared with claudin-1-negative patients (7.1%). Regarding overall survival, the results of the present study suggest a better prognosis for claudin-1-negative patients. In order to elucidate whether claudin-1 overexpression has a significant prognostic impact on squamous cervical cancer, further studies are required.

Effects of an Antagonistic Analog of Growth Hormone-Releasing Hormone on Endometriosis in a Mouse Model and In Vitro

Endometriosis is a benign gynecologic disorder causing dysmenorrhea, pelvic pain, and subfertility. Receptors for the growth hormone-releasing hormone (GHRH) were found in endometriotic tissues. Antagonists of GHRH have been used to inhibit the growth of endometriotic endometrial stromal cells. In this study, the GHRH receptor splice variant (SV) 1 was detected in human endometrial tissue samples by Western blots and quantitative reverse transcription polymerase chain reaction (qRT-PCR). The highest messenger RNA (mRNA) and protein levels of SV1 were found in eutopic endometrium from patients with endometriosis compared to ectopic endometriotic tissues and endometrium from normal patients. The highest expression for GHRH mRNA was found by qRT-PCR in ectopic endometriosis lesions. In an in vivo mouse model with human endometrial explants from patients with endometriosis, 10 μg MIA-602 per day resulted in significantly smaller human endometrial xenotransplants after 4 weeks compared to mice treated with vehicle. The endometrial tissues expressed SV1 before and after xenotransplantation. The proliferation of endometrial stromal cells as well as the endometriosis cell lines 12-Z and 49-Z was decreased by exposure to 1 μM MIA-602 after 72 hours. The protein levels of epithelial growth factor receptors in 12-Z and 49-Z cell lines were reduced 48 and 72 hours after the administration of 1 μM MIA-602. MIA-602 decreased the activation of the MAP-kinases ERK-1/2. Our study demonstrates the presence of SV1 receptor as a target for treatment with GHRH antagonist in endometriosis. Endometrial tissues respond to MIA-602 with inhibition of proliferation in vitro and in vivo. The use of MIA-602 could be an effective supplement to the treatment strategies in endometriosis.

Disrupting Y-Box-Binding Protein 1 Function Using OSU-03012 Prevents Endometriosis Progression in In Vitro and In Vivo Models

The objective of the present study was to test the ability of OSU-03012 (2-amino-N-[4-[5-phenanthren-2-yl-3-(trifluoromethyl)pyrazol-1-yl]phenyl]acetamide), a novel and potent celecoxib-derivative, to impair endometriosis progression in in vitro and in vivo models based on its ability to indirectly block Y-box-binding protein 1 (YB-1) function. 12Z human endometriotic epithelial cells and sexually mature female C57BL/6J mice were treated with OSU-03012. Cellular proliferation was quantified by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazoliumbromid assay. Expression of YB-1 and phosphorylated YB-1 in 12Z cells and endometriotic lesions was evaluated by Western blotting and immunohistochemistry (IHC). The IHC for proliferating cell nuclear antigen was performed. OSU-03012 treatment resulted in decreased YB-1 and its phosphorylated form in both in vitro and in vivo models. Endometriotic lesion size was significantly reduced in OSU-03012-treated mice (27.6 ± 4.0 mm³) compared to those from the control group (50.5 ± 6.9 mm³, P < .0001). A significant reduction in endometriotic epithelial cell proliferation was observed in endometriotic lesions exposed to OSU-03012 treatment ( P = .0346). In conclusion, targeting YB-1 via OSU-03012 showed a potent antiproliferative effect on endometriotic epithelial cells in vitro and in a mouse model of disease.

Expression of cyclooxygenase-2 in cervical cancer is associated with lymphovascular invasion

Cyclooxygenase-2 (COX-2) is associated with carcinogenesis and tumor progression. The current study analyzed the effect of COX-2 expression in patients with invasive squamous cervical cancer. Tissue samples from 123 cervical cancer patients were collected for a retrospective analysis using immunohistochemistry (IHC) with an antibody against COX-2. The clinical and survival data of the patients were analyzed. Positive staining for COX-2 (defined as an immunoreactivity score of ≥4) was detected in 28 patients (23%), with significantly higher percentages of staining in tumor cells compared with peritumoral stroma cells (P<0.001). COX-2 expression was significantly associated with lymphovascular space invasion (LVSI; P=0.017). The association of COX-2 expression with LVSI suggests a possible effect of COX-2 on tumor progression in cervical cancer. Further studies including larger patient collectives are required in order to perform analyses of clinical subgroups and patient survival.

Subtypes of Triple-negative Breast Cancer Cell Lines React Differently to Eribulin Mesylate

BACKGROUND/AIM

Diagnosis of triple-negative breast cancer (TNBC) is associated with adverse prognosis, particularly in cases of chemotherapy resistance. The goal of this analysis was to compare TNBC vs. non-TNBC cell lines and those of distinct TNBC subtypes with regard to sensitivity to eribulin in vitro.

MATERIALS AND METHODS

Breast cancer cell lines were subjected to cell-viability assays, apoptosis analyses, migration and invasion experiments, and quantitative real-time polymerase chain reaction after exposure to eribulin.

RESULTS

Eribulin reduced cell viability in TNBC and non-TNBC cell lines in the sub-nanomolar range. Furthermore, exposure to eribulin induced apoptosis and decreased the rate of migration and invasion. Genes known to induce malignant transformation were differentially expressed after eribulin treatment.

CONCLUSION

Eribulin had a strong antiproliferative effect on breast cancer cell lines, although we did not observe a significant difference between TNBC and non-TNBC cell lines with regard to sensitivity to eribulin.

Abstract P6-08-07: Association between phenotype of triple negative breast cancer cell lines and sensitivity against eribulin mesylate in vitro

Introduction:

Diagnosis of triple negative breast cancer (TNBC) is associated with adverse prognosis particularly in case of chemotherapy resistance. TNBC is a heterogeneous entity and seems to consist of at least six distinct molecular subtypes (Lehman subtypes) with distinct chemotherapy sensitivity. The cytotoxic agent eribulin induces tumor cell apoptosis through depolymerization of the cell spindle apparatus. Based on clinical data it has recently been suggested that TNBC is particularly sensitive against eribulin. The goal of this analysis was to compare (i) TNBC vs. non TNBC lines and (ii) cell lines of distinct TNBC subtypes with regard to eribulin sensitivity in vitro.

Methods:

17 established breast cancer cell lines comprising both TNBC (4 basal-like 1/2; 1 mesenchymal; 3 mesenchymal stem cell; 1 interleukin; 2 luminal AR; 1 unclassified) and non-TNBC (n=5) phenotypes were cultured and subjected to cell viability assay (MTT test), migration experiment (scratch assay), apoptosis analysis (Western Blot experiment for PARP cleavage) and quantitative RT-PCR analysis (for GABRP gene expression) after exposure to eribulin or control. Furthermore, gene expression of 8 genes known to induce malignant transformation (MMP7, ELF5, YBX1, RARRES1, PRNP, SOX 10, EGFR and GABRP) was analyzed via quantitative RT-PCR analysis in the triple negative cell line MDA-MB 231 after exposure to eribulin or control.

Results:

The effect of eribulin on the cell viability varied to a lesser extent among the TNBC compared to the non-TNBC cell lines though we could not observe a significant difference between both groups. Mentionable the TNBC cell line DU 4475 representing the interleukin phenotype displayed a significant stronger resistance to eribulin compared to all other phenotypes. A decelerated migration could be observed in the TNBC cell line MDA-MB 231 after exposure to the IC50 concentration of eribulin compared to non-treated cells.

Induction of apoptosis by eribulin treatment was verified by PARP cleavage in various TNBC cell lines. GABRP known to be overexpressed especially in basal like TNBC showed a slight increase in gene expression after exposure to eribulin in various phenotypes of TNBC - most prominent in MDA-MB 231. Additionally, upregulation of ELF5 and downregulation of YBX1 and PRNP, and, to a lesser extent, of MMP7 and SOX 10 gene expression could be investigated in MDA-MB 231 after eribulin treatment.

Conclusion:

We did not observe a significant association with regard to eribulin sensitivity between TNBC and non-TNBC. Chemotherapy sensitivity varied to a lesser extent among TNBC cell lines compared to non-TNBC cell lines. Eribulin inhibits cell proliferation and migration, induces apoptosis in TNBC, and influences gene expression of overexpressed genes in TNBC known to participate in and induce malignant transformation.

Though the current work did not explicitly specify one phenotype of TNBC for eribulin treatment regarding chemotherapy sensitivity, we identified possible target genes influenced by eribulin treatment, e. g. GABRP, and therefore need further investigation for a potential treatment approach combining eribulin with e. g. GABRP inhibitor.

Citation Format: Bräutigam K, Mitzlaff K, Uebel L, Steinert G, Köster F, Polack S, Rody A, Liedtke C. Association between phenotype of triple negative breast cancer cell lines and sensitivity against eribulin mesylate in vitro. [abstract]. In: Proceedings of the Thirty-Eighth Annual CTRC-AACR San Antonio Breast Cancer Symposium: 2015 Dec 8-12; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2016;76(4 Suppl):Abstract nr P6-08-07.

Combined treatment of breast cancer cell lines with vitamin D and COX-2 inhibitors

BACKGROUND

Vitamin D is known for its anti-cancerogenous potential. Prostaglandin E2 (PGE2) is a proliferation and inflammation activating agent. The production of PGE2 is dependent on the activity of cyclooxygenase-2 (COX-2). A link between vitamin D and PGE2 metabolism was recently shown.

MATERIALS AND METHODS

In MDA-MB-231 and MCF-7 breast cancer cell lines we investigated the influence of calcitriol and the COX-2 inhibitor celecoxib regarding cell growth via MTT test, as well as on the protein and mRNA expression of COX-2 using western blot and qRT-PCR.

RESULTS

The proliferation of MCF-7 and MDA-MB-231 was inhibited by both calcitriol and the COX-2 inhibitor celecoxib and even stronger by their combination. Moreover, calcitriol inhibited the COX-2 protein expression in MDA-MB-231, as well as the COX-2 mRNA expression in both cell lines.

CONCLUSION

The combination of calcitriol and celecoxib demonstrated a cooperative growth-inhibiting effect in breast cancer cell lines.

Vitamin D inhibits ovarian cancer cell line proliferation in combination with celecoxib and suppresses cyclooxygenase-2 expression

BACKGROUND

Vitamin D exhibits multiple anti-proliferative and pro-differentiating actions. Prostaglandin-(PG)E2 is a tumor-promoting tissue hormone anabolized by cyclooxygenase-2 (COX-2). Recently, a link between the PG and vitamin D metabolism was reported.

MATERIALS AND METHODS

The influence of calcitriol and celecoxib on the proliferation of ovarian cancer cell lines was measured and the impact of calcitriol on the protein and mRNA expression of COX-2 was quantified by western blot and qRT-PCR, respectively.

RESULTS

After COX-2 induction with interleukin (IL)-1β, 10 μM celecoxib did not significantly inhibit the proliferation of OVCAR-3 cells, whereas calcitriol showed such an effect; however, the combination of the two substances had an additive influence. After induction by IL-1β, calcitriol inhibited the COX-2 protein, as well as its mRNA expression significantly in OVCAR-3 and SKOV-3 cells.

CONCLUSION

These data suggest a correlation between PG and vitamin D metabolism in their anti-tumorigenic activity in ovarian carcinomas.

Growth-modulatory effects of heparin and VEGF165 on the choriocarcinoma cell-line JEG-3 and its expression of heparanase

BACKGROUND

Expression of heparanase (HPSE) in tumor cells is strongly associated with invasion, metastasis and angiogenesis. It also plays a key role during pregnancy, in processes of implantation as well as placentation. Vascular endothelial growth factor (VEGF) and heparin are known to alter HPSE expression, with heparin given prophylactically to women with a history of placenta-mediated complications in subsequent pregnancies.

MATERIALS AND METHODS

We examined the growth-modulatory effects of different concentrations of heparin and VEGF on the choriocarcinoma cell-line JEG-3 and the expression of heparanase under VEGF and heparin by proliferation assays, PCR, and western blot.

RESULTS

Proliferation of JEG-3 cells was induced by heparin in a dose-dependent manner, whereas highly concentrated VEGF led to a decreased cell proliferation. Both agents did not influence the HPSE-expression.

CONCLUSION

The presumed pregnancy-protecting effects of heparin may partially be due to an increase of trophoblast proliferation and not via regulation of HPSE expression.

Slow-freezing versus vitrification for human ovarian tissue cryopreservation

PURPOSE

Ovarian tissue can be cryopreserved prior to chemotherapy using either the slow-freezing or the vitrification method; however, the data on the equality of the procedures are still conflicting. In this study, a comparison of the cryo-damage of human ovarian tissue induced by either vitrification or slow-freezing was performed.

METHODS

Ovarian tissue from 23 pre-menopausal patients was cryopreserved with either slow-freezing or vitrification. After thawing/warming, the tissue was histologically and immunohistochemically analyzed and cultured in vitro. During tissue culture the estradiol release was assessed.

RESULTS

No significant difference was found in the proportion of high-quality follicles after thawing/warming in the slow-freezing and vitrification group, respectively (72.7 versus 66.7 %, p = 0.733). Estradiol secretion by the ovarian tissue was similar between groups during 18 days in vitro culture (area-under-the-curve 5,411 versus 13,102, p = 0.11). Addition of Sphingosine-1-Phosphate or Activin A to the culture medium did not alter estradiol release in both groups. The proportion of Activated Caspase-3 or 'Proliferating-Cell-Nuclear-Antigen' positive follicles at the end of the culture period was similar between slow-freezing and vitrification.

CONCLUSION(S)

Slow-freezing and vitrification result in similar morphological integrity after cryopreservation, a similar estradiol release in culture, and similar rates of follicular proliferation and apoptosis after culture.

The effects of cetrorelix and triptorelin on the viability and steroidogenesis of cultured human granulosa luteinized cells

BACKGROUND

We investigated the effects of the gonadotropin-releasing hormone (GnRH) agonist triptorelin as well the GnRH antagonist cetrorelix those of on the viability and steroidogenesis in human granulosa luteinized (hGL) cell cultures.

MATERIALS AND METHODS

The hGL cells were obtained from 34 women undergoing ovarian stimulation for IVF treatment. The cells were cultured for 48 h with or without 1 nM or 3 nM of cetrorelix or triptorelin in serum-free media. The cell viability was evaluated by the MTT [3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide] assay. The concentrations of estradiol and progesterone in culture supernatants were measured by ELISA.

RESULTS

Treatment with triptorelin slightly increased cell viability, whereas treatment with 3 nM cetrorelix led to a significant decrease. Estradiol concentrations were reduced with 3 nM triptorelin. Cultures treated with high-dose of either cetrorelix or triptorelin tended to secrete less progesterone than controls.

CONCLUSION

Cetrorelix significantly reduces the viability of hGL cells. Triptorelin and cetrorelix may have minor effects on steroidogenesis. These results suggest that GnRH analogues may influence ovarian functions.

Expression of prostaglandin- and vitamin D-metabolising enzymes in benign and malignant breast cells

BACKGROUND

Cyclooxygenase-2 (COX-2) plays a crucial role in prognosis of malignancy and has been associated with carcinogenesis, particularly neoangiogenesis and tumor progression. 15-Hydroxyprostaglandin dehydrogenase (15-PGDH) is described as a tumour suppressor in cancer. The antiproliferative effects of calcitriol [1,25(OH)(2)D(3)] mediated via the vitamin D receptor (VDR) render vitamin D a promising target in breast cancer therapy.

MATERIALS AND METHODS

The expression of prostaglandin (PG)-metabolizing enzymes, vitamin D-metabolising enzymes and VDR were determined in benign and malignant breast cell lines using western blot analysis.

RESULTS

We detected an inverse correlation between the two types of metabolism, a reduced VDR expression in the malignant breast cell lines, and therefore an insufficient induction of 24-hydroxylase in the malignant cells.

CONCLUSION

We suggest the possibility of dysregulation of vitamin D-metabolizing enzymes in malignant breast cell lines.

Correlation of prostaglandin metabolizing enzymes and serum PGE2 levels with vitamin D receptor and serum 25(OH)2D3 levels in breast and ovarian cancer

BACKGROUND

Vitamin D and its active form calcitriol have multiple effects in cancer cells, such as anti-proliferative effects, induction of apoptosis and cell cycle arrest. There is a link between vitamin D metabolism and inflammatory processes, which should be considered in cancer therapy. An association between these two types of metabolism is also observed in breast and ovarian cancer. These inflammatory processes are based on an increase of cyclooxygenase-2 (COX-2) activity. The current study aimed to evaluate the expression of prostaglandin-metabolising enzymes COX-2 and 15-hydroxyprostaglandin-dehydrogenase (15-PGDH) along with the vitamin D receptor (VDR) in benign and malignant breast and ovarian tissues.

PATIENTS AND METHODS

VDR, COX-2, 15-PGDH and prostanoid receptor E2/E4 expression were measured in tissues by western blot analysis. Additionally, plasma 25(OH)(2)D(3) and PGE(2) levels were measured in healthy patients and cancer patients.

RESULTS

We detected an elevated COX-2 and inversely a lowered VDR expression in cancer patients compared to healthy women. Breast cancer patients diagnosed during wintertime had a significantly lower serum level of 25(OH)(2)D(3); PGE(2) serum levels were higher in both types of cancer.

CONCLUSION

These results support the idea of a link between prostaglandin and vitamin D metabolism in regards to their influences on breast and ovarian cancer.

Influence of calcitriol on prostaglandin- and vitamin D-metabolising enzymes in benign and malignant breast cell lines

BACKGROUND

Cyclooxygenase-2 (COX-2) is a potential molecular prognostic factor for breast cancer, and calcitriol [1,25(OH)(2)D(3)], the biologically active form of vitamin D, is a promising target in breast cancer therapy.

MATERIALS AND METHODS

The influence of calcitriol on the proliferation and the effects of calcitriol on the expression of prostaglandin- and vitamin D-metabolising enzymes were examined in benign and malignant breast cells.

RESULTS

Calcitriol inhibited the proliferation of MCF-10F and MCF-7 cells but not of invasive MDA-MB-231 cells and reduced the expression of COX-2 and 15-hydroxyprostaglandin dehydrogenase (15-PGDH) in the benign breast cell line MCF-10F. Furthermore, dysregulation in vitamin D-metabolising proteins was detected, especially in MDA-MB-231 cells.

CONCLUSION

These results suggest dysregulation of vitamin D metabolism and a lack of a possible influence of calcitriol on the metabolism of prostaglandins in the malignant breast cell lines.

Vitamin D, calcidiol and calcitriol regulate vitamin D metabolizing enzymes in cervical and ovarian cancer cells

BACKGROUND

The vitamin D metabolizing enzymes 25-, 1α- and 24-hydroxylase are expressed in malignant cells of the cervix and the ovaries. The aim of this study was to obtain further information about the regulation of the aforementioned enzymes by vitamin D, calcidiol and calcitriol in cervical and ovarian cancer.

MATERIALS AND METHODS

The human cervical adenocarcinoma cell line HeLa and the human ovarian adenocarcinoma cell line OVCAR-3 were incubated with vitamin D, calcidiol and calcitriol. The influence of vitamin D and its metabolites on the expression of 25-, 1α- and 24-hydroxylase was assessed by real-time RT-PCR.

RESULTS

Calcitriol significantly increased the 24-hydroxylase mRNA levels in HeLa and OVCAR-3 cells. The expression of 25- and 1α-hydroxylase was not regulated in a statistically significant manner.

CONCLUSION

These results suggest that in HeLa as well as OVCAR-3 cell lines, the metabolism of vitamin D is regulated via the expression of the catabolizing 24-hydroxylase.

Concentrations of inflammatory cytokines and the outcome in ICSI cycles

The aim of this study was to measure circulating and intrafollicular concentrations of three inflammatory cytokines from women undergoing ovarian stimulation in order to determine their prognostic value in the outcome of intracytoplasmic sperm injection/embryo transfer cycles.

MATERIALS AND METHODS

A total of 72 women following ovarian stimulation and intracytoplasmic sperm injection were included. Blood serum samples were drawn at the day of chorionic gonadotropin administration. Follicular fluids were collected at the day of oocyte retrieval. The total fractions of tumor necrosis factor alpha, interleukin (IL)-1beta and IL-6 were measured with commercially available immunoassays.

RESULTS

The concentrations of IL-1beta, both in serum and follicular fluids, were significantly different between ICSI cycles that resulted in pregnancy and those that failed. The concentrations of the other two cytokines did not significantly differ between successful and unsuccessful cycles.

CONCLUSION

The circulating and intrafollicular concentrations of IL-1beta seem to be related to the pregnancy outcome in ICSI cycles of healthy women.

Overexpression of polycomb protein BMI-1 in human specimens of breast, ovarian, endometrial and cervical cancer

INTRODUCTION

The polycomb group (PcG) proteins form chromatin-modifying complexes that are commonly deregulated in cancer. The PcG protein BMI-I is overexpressed by various tumours and thus may contribute to malignant transformation. The current study investigated the expression of BMI-I in human specimens of breast, ovarian, endometrial and cervical cancer.

MATERIALS AND METHODS

Expression of BMI-I was evaluated in human ovarian cancer samples by Western blot analysis and immunohistochemistry (IHC) and compared to healthy ovarian tissue. BMI-I expression in human specimens of breast, endometrial and cervical cancer was evaluated by IHC and then compared with the respective benign tissues.

RESULTS

BMI-I was significantly (p<0.05) overexpressed in human breast, ovarian, endometrial and cervical cancer specimens as compared to benign controls. BMI-I expression was also more pronounced in the ovarian cancer samples as demonstrated by Western blot analysis. In human breast cancer samples, BMI-I expression was most pronounced in the invasion front of the tumour.

CONCLUSION

The current study showed for the first time that the BMI-I protein is significantly overexpressed in ovarian, endometrial and cervical cancer and may thus be a potential target for novel antitumor therapies.

Induction of programmed cell death by inhibition of AKT with the alkylphosphocholine perifosine in in vitro models of platinum sensitive and resistant ovarian cancers

PURPOSE

We analyzed the anti-tumor effect and the mechanism of action of perifosine, an orally active alkylphospholipid AKT inhibitor using in vitro models of human ovarian cancer.

METHODS

Ovarian cancer cells OAW42, PA-1, SKOV3, and A2780 as well as platinum resistant A2780cis cells were incubated with increasing concentrations of perifosine, with and without multi-caspase inhibitor zVAD-FMK. The effect of a combined treatment with cisplatin and perifosine was investigated in OAW42, SKOV3, A2780 and A2780cis cells. Cytotoxic effects of perifosine were analyzed using crystal violet staining, FACS analysis of DNA content as well as Annexin V/propidium iodide-double staining. The effect of perifosine on AKT phosphorylation was determined by Western blotting.

RESULTS

Perifosine displayed anti-tumor activity in all five cell lines, which increased time-dependently. While IC(50) values at 24 h were >40 μM, IC(50) values after 72 h decreased to 10 μM in OAW42 and 25 μM in PA-1 and 30 μm in SKOV3 cells. In platinum resistant A2780cis cells perifosine showed good antiproliferative activity (IC(50) = 3 μm). At adequate doses, perifosine increased cytotoxic effects of cisplatin in OAW42, A2780 and A2780cis cell. Anti-tumor activity of perifosine was not confined to a specific phase of the cell cycle and could not be decreased by the pan-caspase inhibitor zVAD-FMK. AnnexinV/propidium iodide-double staining after treatment with perifosine was not indicative of classical apoptosis. AKT phosphorylation was dose-dependently inhibited by perifosine.

CONCLUSIONS

Perifosine showed substantial cytotoxic effects in various in vitro models of ovarian cancer. Since anti-tumor effects were not confined to platinum-sensitive cells perifosine seems to be a good candidate for clinical studies in patients especially with platinum resistant ovarian cancer.

Triple-negative breast cancers express receptors for luteinizing hormone-releasing hormone (LHRH) and respond to LHRH antagonist cetrorelix with growth inhibition

The aim of the present study was to evaluate the expression of receptors for luteinizing hormone-releasing hormone (LHRH) in human specimens of triple-negative breast cancers (TNBC). In addition, we used in vitro and in vivo models of TNBC to investigate if these receptors are suitable targets for the treatment with the LHRH antagonist cetrorelix. Receptors for LHRH were expressed in all tumor samples and in the TNBC cell lines HCC1806 and HCC1937. The proliferation of both TNBC cell lines was significantly inhibited in vitro by 1 microM cetrorelix. Injections of 3 mg cetrorelix on day 1 and 21 resulted in a significant growth inhibition of HCC1806 tumors xenografted into nude mice. Tumors of mice treated with cetrorelix expressed less mRNA for EGFR and HER3 receptors than untreated tumors. After treatment of cells with Cetrorelix a flow cytometric analysis of the cell cycle revealed a decrease in S-phase. Given the low toxicity and clinical availability of cetrorelix, this peptide antagonist should be considered for phase II studies in patients with advanced TNBC.

Immunohistochemistry of DNA mismatch repair enzyme MSH2 is not correlated with prognostic data from endometrial carcinomas

BACKGROUND

The human Mut-S-homolog-2 (MSH2) is part of the DNA mismatch repair system (MMR). Mutations in genes of the MMR are a predisposition to hereditary non-polyposis colorectal cancer (HNPCC). In women, MMR gene mutations may lead to primary endometrial cancer (EC). The important function of the MMR for the integrity of the DNA during replication makes it probable that the MMR might also be involved in the development and the course of sporadic carcinomas. Insufficient MMR activity or expression levels could be prognostic markers of the disease.

PATIENTS AND METHODS

Immunohistochemical analysis of MSH2 was performed in 86 tumor samples from patients with EC.

RESULTS

Compared to known tumor markers, namely estrogen and progesterone receptors, histopathological grading, TNM stage and FIGO classification, no significant correlation between MSH2 immunoreactivity and EC was found.

CONCLUSION

MSH2 immunohistochemical analysis is not of prognostic value for endometrial carcinoma.

Effective treatment of triple-negative breast cancer with targeted cytotoxic somatostatin analogue AN-162 (AEZS-124)

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Background: Triple negative breast cancers (TNBC) represent a distinct subtype of breast cancer being negative to ER, PR and HER2 and are associated with poor prognosis. Limited systemic treatment options exist for TNBC. TNBC cells express somatostatin receptors (SSTR). Therefore, to investigate preclinical characteristics of TNBC we used a novel targeted cytotoxic somatostatin analogue AN-162 containing doxorubicin (DOX) which binds to the subtypes 2, 3 and 5 of SSTR. Methods: The expression of SSTR in HCC 1806 human TNBC cell line was detected by RT-PCR. Cytotoxic effect of AN-162 in vitro was visualized by ethidium bromide staining fluorescence microscopy. Internalization of AN-162 into HCC 1806 cells was tested by 125Iodide-labeled AN-162 uptake assays and the presence of DOX in the nucleus was measured by fluorescence assays after separating the nucleus from the cytoplasm. For in vivo experiments, HCC 1806 TNBC cells were xenografted subcutaneously into nude mice which were then randomized into four groups receiving AN-162, DOX, an unconjugated mixture of DOX and somatostatin analogue RC-160 at the same equimolar dose of 2.5 μmol/kg (1.45 mg/kg Dox equivalent) i.v. (q7d 4x) and vehicle solution control. Results: HCC 1806 TNBC cell line was positive for the expression of all five SSTR receptor subtypes. Ethidum bromide staining of cells treated with 2.5 μM of AN-162 for 30 min demonstrated cell death after 24h by fluorescence microscopy. Uptake assays with AN-162 showed specific internalization of AN-162 into the cells mediated through the sstrs. After treatment of the cells with 2.5 μM AN-162 for 10 or 30 min, DOX could be detected in the nucleus by fluorescence assays. In vivo, AN-162 significantly (p<0.05) inhibited tumor growth of HCC 1806 xenografts compared to Control, DOX and the unconjugated mixture of DOX+RC-160 from day 14 and the inhibition remained significant until the end of the study on day 35. Conclusions: Our results indicate that treatment with targeted cytotoxic somatostatin analogue AN-162 produces a greater inhibition of tumor growth than DOX alone in somatostatin receptor positive TNBC. Our findings support the concept of targeted chemotherapy based on cytotoxic peptide analogues for the treatment of breast cancer and other cancers.

No significant financial relationships to disclose.

Inhibition of estrogen receptor positive and negative breast cancer cell lines with a growth hormone-releasing hormone antagonist

GHRH antagonists have been shown to inhibit growth of various human cancer cell lines xenografted into nude mice including estrogen receptor negative human breast cancers. Previous observations also suggest that GHRH locally produced in diverse neoplasms including breast cancer might directly affect proliferation of tumor cells. In the present study we demonstrate that a novel highly potent GHRH antagonist JMR-132 strongly inhibits the proliferation of both estrogen receptor negative SKBR 3 and estrogen receptor positive ZR 75 human breast cancer cell lines in vitro. The proliferation in vitro of ZR 75 and SKBR 3 was increased after direct stimulation with GHRH(1-29)NH2. The GHRH antagonist JMR-132 had a significant antiproliferative activity in the absence of GHRH and nullified the proliferative effect of GHRH in these cell lines. SKBR 3 and ZR 75 expressed the GHRH ligand as well as the pituitary type of GHRH-receptor, which likely appears to mediate the antiproliferative mechanisms in these cell lines. These in vitro results suggest that JMR-132 is a potent inhibitor of breast cancer growth, independent of the estrogen receptor status. Further investigations on the combination treatment with endocrine agents affecting the estrogen pathway and GRHR antagonists are needed in order to improve the treatment of breast cancer.

Semen DNA fragmentation index, evaluated with both TUNEL and Comet assay, and the ICSI outcome

BACKGROUND

In intracytoplasmic sperm injection (ICSI), there is always a risk of using spermatozoa with damaged DNA. The purpose of this study was to evaluate the percentage of spermatozoa with DNA fragmentation in processed semen samples used in ICSI cycles and to investigate the relationship between the DNA fragmentation index (DFI) and the ICSI outcome.

PATIENTS AND METHODS

Fifty-six couples undergoing ICSI treatment were included. DFI was evaluated, by both terminal deoxynucleotidyl transferase-mediated dUDP nick-end labelling (TUNEL) and single cell gel electrophoresis (Comet) assays, in the processed semen samples used for ICSI.

RESULTS

Of the processed semen samples 17.85% had > or =10% spermatozoa with fragmented DNA. There was no correlation between DFI and the ICSI outcome. DFI assessed by the TUNEL assay was negatively correlated with sperm concentration, progressive motility and sperm morphology.

CONCLUSION

A considerable proportion of processed semen samples used for ICSI have a high DFI. However, DFI of the processed semen samples does not seem to be related to the ICSI outcome.

Immunohistochemistry of proteins for DNA mismatch repair in correlation to prognostic factors of mammarian cancer

Mutations in genes of the DNA mismatch repair system (MMR) are strongly linked to the development of hereditary non-polyposis colorectal cancer and play a significant role in sporadic cancer too. Besides the repair of chromosomal mismatches produced during replication, the MMR is the linkage of DNA mismatches to cell cycle control. Proteins of the MMR are necessary for the induction of apoptosis in response to non-tolerable amounts of DNA damage. We correlated the immunoreactivity of the MMR proteins hMSH2, hMLH1 and PMS2 to the immunoreaction of p53, the proliferation marker Ki67 and clinical prognosis factors such as tumor grading and staging, steroid receptor expression and hemangiosis carcinomatosa or lymphangiosis carcinomatosa in 200 samples from patients with diagnosed breast cancer. No correlation could be detected among the expression of the three MMR-proteins hMSH2, hMLH1 and PMS2. The expression of hMSH2 correlated positively with the expression of p53, with the appearance of distant metastases, low differentiation and the appearance of hemangiosis carcinomatosa and lymphangiosis carcinomatosa, while it negatively correlated with the expression of the estrogen receptor. No correlation was detected between hMLH1 or PMS2 and any of the investigated factors. The expression of hMSH2 seems to be related with predictors of an unfavorable course of disease in breast cancer.

Immunohistochemistry of proteins for DNA mismatch repair in correlation to prognostic factors of mammarian cancer

Mutations in genes of the DNA mismatch repair system (MMR) are strongly linked to the development of hereditary non-polyposis colorectal cancer and play a significant role in sporadic cancer too. Besides the repair of chromosomal mismatches produced during replication, the MMR is the linkage of DNA mismatches to cell cycle control. Proteins of the MMR are necessary for the induction of apoptosis in response to non-tolerable amounts of DNA damage. We correlated the immunoreactivity of the MMR proteins hMSH2, hMLH1 and PMS2 to the immunoreaction of p53, the proliferation marker Ki67 and clinical prognosis factors such as tumor grading and staging, steroid receptor expression and hemangiosis carcinomatosa or lymphangiosis carcinomatosa in 200 samples from patients with diagnosed breast cancer. No correlation could be detected among the expression of the three MMR-proteins hMSH2, hMLH1 and PMS2. The expression of hMSH2 correlated positively with the expression of p53, with the appearance of distant metastases, low differentiation and the appearance of hemangiosis carcinomatosa and lymphangiosis carcinomatosa, while it negatively correlated with the expression of the estrogen receptor. No correlation was detected between hMLH1 or PMS2 and any of the investigated factors. The expression of hMSH2 seems to be related with predictors of an unfavorable course of disease in breast cancer.

Cytokine profile in cases with premature elevation of progesterone serum concentrations during ovarian stimulation

The aim of this study was to investigate the concentrations of vascular endothelial growth factor (VEGF), basic fibroblast growth factor (bFGF), leptin, tumor necrosis factor-alpha, interleukin (IL)-1beta and IL-6, in cycles with a premature rise of serum progesterone. 25 intracytoplasmic sperm injection (ICSI) cycles with (Group 1) and 25 ICSI cycles without a premature progesterone elevation (Group 2) were included. The cut-off value of serum progesterone on the day of human chorionic gonadotropin (hCG) administration was 0.9 ng/ml. The indication for ICSI was male factor infertility exclusively. On the day of hCG injection, serum IL-6, VEGF and bFGF were significantly higher in Group 1 (7.7+/-24.5 pg/ml, 290.2+/-161.4 pg/ml and 15.7+/-8.2 ng/ml respectively) than in Group 2 (1.7+/-0.7 pg/ml, 175.2+/-92.1 pg/ml, and 9+/-1.6 ng/ml respectively). On the day of follicular puncture, serum cytokine concentrations were similar in the two groups. IL-6 intrafollicular concentrations were higher in Group 1 (14.7+/-20.7 pg/ml) than in Group 2 (9+/-9.3 pg/ml, p=0.031). There were no differences regarding the ICSI outcome. Patients with serum progesterone above 0.9 ng/ml, have elevated serum concentrations of IL-6, VEGF, and bFGF, as well as elevated intrafollicular concentrations of IL-6. The outcome of ICSI cycles is not associated with premature elevation of progesterone when the cut-off value is set at 0.9 ng/ml.

Correlation of DNA mismatch repair protein hMSH2 immunohistochemistry with p53 and apoptosis in cervical carcinoma

BACKGROUND

Mutations in genes of the DNA mismatch repair system (MMR) are linked to hereditary non-polyposis colorectal cancer and also play a role in sporadic cancer. Besides its repair function, the MMR is the linkage of DNA mismatch recognition to the cell cycle control.

MATERIALS AND METHODS

The correlation between the immunoreactivity of the MMR protein hMSH2 and p53, apoptosis, clinical prognosis factors and the survival rate in 102 samples of cervical carcinoma was determined.

RESULTS

hMSH2 immunoreactivity was correlated with p53 and weakly correlated with apoptosis. hMSH2 immunoreactivity could not be correlated to any tumour markers, while apoptosis correlated significantly with T stage, FIGO classification and the relative risk of death from cervical cancer.

CONCLUSION

In cervical cancer, the processes of DNA mismatch repair, cell cycle control and apoptosis seemingly act in concert. Decreased expression of the hMSH2 mismatch repair protein might lead to a failure in the induction of apoptosis.

Cell-specific enhancement of liposomal transfection by steroids in steroid receptor expressing cells

The DNA transfer efficiency in liposomal versus viral transfection is very low, mainly due to an insufficient nuclear transport of the delivered DNA after its endocytotic uptake to the cell. Ligand activation of intracellular steroid receptors and their subsequent mobilization to the nucleus could result in a co-transport of DNA to the nucleus. The augmentation of nuclear transport of DNA after steroid addition might cause enhanced transfection efficiency. We used cell lines from gynecologic malignoma expressing steroid receptors, such as T47D and Mcf-7 breast cancer cell lines, as well as receptor-negative cell lines, such as Hec1A from endometrium carcinoma or the breast cancer cell line MDA-MB-231. The cells were transfected by the liposomal transfection agent Dotap with the gene for firefly-luciferase as a reporter gene and transfection efficiencies were determined in the luciferase assay. We compared the effect of the addition of cholesterol and steroids in different cell lines on the transfection efficiency. The addition of cholesterol to transfection agents led to an enhancement of the luciferase activity in all cell lines. Steroids enhanced the transfection efficiency only in receptor-positive cell lines. The transfection efficiencies of HEC-1A or MDA-MB-231 cells were not enhanced by steroids. A progesterone preincubation of receptor-positive T47D cells resulted in a decrease of progesterone receptors and afterwards the progesterone enhanced transfection was dramatically diminished. We presume that the transfection enhancement by steroids is dependent on increased nuclear import of the delivered DNA only in the presence of steroid receptors. Steroid enhancement of transfection is different from the benefit of cholesterol for transfection that acts on general cellular properties or the transfection complex as such. Liposomal transfection in combination with steroids might be useful for a cell-specific enhancement of gene transfer for example in gynecological malignoma where subgroups are expressing high levels of steroid receptors.