PARP inhibitors promote stromal fibroblast activation by enhancing CCL5 autocrine signaling in ovarian cancer

AbstractCancer-associated fibroblasts (CAFs) play significant roles in drug resistance through different ways. Antitumor therapies, including molecular targeted interventions, not only effect tumor cells but also modulate the phenotype and characteristics of CAFs, which can in turn blunt the therapeutic response. Little is known about how stromal fibroblasts respond to poly (ADP-ribose) polymerase inhibitors (PARPis) in ovarian cancer (OC) and subsequent effects on tumor cells. This is a study to evaluate how CAFs react to PARPis and their potential influence on PARPi resistance in OC. We discovered that OC stromal fibroblasts exhibited intrinsic resistance to PARPis and were further activated after the administration of PARPis. PARPi-challenged fibroblasts displayed a specific secretory profile characterized by increased secretion of CCL5, MIP-3α, MCP3, CCL11, and ENA-78. Mechanistically, increased secretion of CCL5 through activation of the NF-κB signaling pathway was required for PARPi-induced stromal fibroblast activation in an autocrine manner. Moreover, neutralizing CCL5 partly reversed PARPi-induced fibroblast activation and boosted the tumor inhibitory effect of PARPis in both BRCA1/2-mutant and BRCA1/2-wild type xenograft models. Our study revealed that PARPis could maintain and improve stromal fibroblast activation involving CCL5 autocrine upregulation. Targeting CCL5 might offer a new treatment modality in overcoming the reality of PARPi resistance in OC.

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Targeting INHBA in Ovarian Cancer Cells Suppresses Cancer Xenograft Growth by Attenuating Stromal Fibroblast Activation

Disease Markers ◽

10.1155/2019/7275289 ◽

2019 ◽

Vol 2019 ◽

pp. 1-13 ◽

Cited By ~ 2

Author(s):

Xiaoting Li ◽

Zongyuan Yang ◽

Sen Xu ◽

Zhengzheng Wang ◽

Ping Jin ◽

...

Keyword(s):

Ovarian Cancer ◽

Cancer Cells ◽

Transforming Growth Factor ◽

Ovarian Cancer Cells ◽

Stromal Fibroblast ◽

Stromal Fibroblasts ◽

Fibroblast Activation ◽

Xenograft Growth ◽

Risk Of Mortality

INHBA-encoded inhibin β A is a member of the transforming growth factor-β (TGF-β) superfamily. INHBA has been reported to be implicated in the progression of multiple types of cancer including ovarian cancer (OC). However, the mechanisms by which INHBA affects OC progression are not well-characterized. The aim of our study was to explore the prognostic value of INHBA for different stages and grades of OC and to identify the possible mechanisms by which INHBA promotes OC progression. Our results demonstrated that INHBA was specifically expressed in OC epithelium, and higher expression was associated with higher risk of mortality in patients with advanced and higher-grade serous OC (SOC). In addition, knockdown of INHBA in cancer cells impaired cancer xenograft growth through reducing OC stromal fibroblast activation in vivo. Further results confirmed that Smad2 signaling pathway was involved in INHBA-induced stromal fibroblast activation, and inhibiting this pathway could effectively reverse activation of stromal fibroblasts. In summary, our results showed that blocking INHBA in cancer cells may be a potential therapeutic strategy to inhibit SOC progression.

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Evaluation of a RAD51 functional assay in advanced ovarian cancer, a GINECO/GINEGEPS study.

Journal of Clinical Oncology ◽

10.1200/jco.2021.39.15_suppl.5513 ◽

2021 ◽

Vol 39 (15_suppl) ◽

pp. 5513-5513

Author(s):

Felix Blanc-Durand ◽

Elisa Yaniz ◽

Catherine Genestie ◽

Etienne Rouleau ◽

Dominique Berton ◽

...

Keyword(s):

Ovarian Cancer ◽

Dna Damage ◽

Tumor Cells ◽

Parp Inhibitor ◽

Advanced Ovarian Cancer ◽

Progression Free Survival ◽

Parp Inhibitors ◽

Cycle Phase ◽

Small Subset ◽

Functional Assay

5513 Background: Homologous recombination deficiency (HRD), defined as BRCA1/2 mutation ( BRCAmut)or high genomic instability, is currently used to identify patients (pts) with epithelial ovarian cancer (EOC) most likely to benefit from PARP inhibitors. While these genomic tests are useful, they are imperfect: some BRCAm EOC demonstrate primary PARPi resistance and some HR-proficient benefit. Another approach to evaluate HRD is to measure the capacity of tumor cells to recruit nuclear RAD51 foci during S/G2 phase in the presence of double strand DNA damage using multiplexed immunofluorescence (IF) for RAD51, geminin (GMN) and yH2AX. We aimed to describe for the 1st time HRD using this RAD51 functional assay in EOC and correlate RAD51 status to platinum response and BRCAmut. Methods: Tumor samples and clinical data were collected prospectively from pts in the randomized CHIVA trial of neoadjuvant platinum chemotherapy +/- nintedanib. IF for RAD51, GMN, and DAPI was performed on a 3uM slide from FFPE blocks, where feasible, yH2AX was positively scored on a consecutive slide. Tumors were considered RAD51-deficient if < 10% of gem+ tumor cells (TC) had > 5 RAD51+ foci. BRCAmut were identified by NGS. Results: 155 baseline chemotherapy naïve EOC samples were available. All were advanced stage (IIIC/IV), 75% were G3, 7% G2, 2% G1, and 16% grade UK. A contributive RAD51 result was obtained for 90% (139/155) of samples. Contributive NGS results were available for 130 samples. Overall, yH2AX scores were high (median % TC+: 86%, IQR: 56%-100%) confirming the presence of significant basal DNA damage in high grade EOC. Only 8 samples were yH2AX-low, including two of the three G1 tumors. In contrast, 55% (76/155) of samples were considered RAD51-deficient (score < 10%). With regard to outcome, pts with RAD51-deficient tumors had significantly higher overall response rates to neoadjuvant platinum (68% vs 37%, p = 0.04) and significantly longer median progression-free survival (HR 0.50, IC95% 0.25-0.98, p = 0.02). Considering BRCA status, 15% of tumors harbored a deleterious BRCAmut and 67% of these were RAD51-deficient. Importantly among BRCAmut EOC, the RAD51-proficient tumors had significantly poorer response to neoadjuvant chemotherapy (RR = 17% vs 75%, p = 0.02). Conclusions: We evaluated a novel functional assay of HR functionality in advanced EOC. The assay requires minimal tissue and yields contributive results in 90% of cases. Overall, EOC demonstrate high levels of basal DNA damage, yet 55% fail to recruit RAD51 foci during S/G2 cell cycle phase. These RAD51-deficient EOC have improved outcome after neoadjuvant platinum. Conversely, the RAD51 assay also identified a small subset of RAD51-high BRCAmut tumors with poor platinum response. Whether this RAD51 functional assay may also predict PARP inhibitor benefit is currently being investigated.

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PARP Inhibition Activates STAT3 in Both Tumor and Immune Cells Underlying Therapy Resistance and Immunosuppression In Ovarian Cancer

Frontiers in Oncology ◽

10.3389/fonc.2021.724104 ◽

2021 ◽

Vol 11 ◽

Author(s):

Antons Martincuks ◽

Jieun Song ◽

Adrian Kohut ◽

Chunyan Zhang ◽

Yi-Jia Li ◽

...

Keyword(s):

Ovarian Cancer ◽

Cancer Cells ◽

Tumor Cells ◽

Immune Cells ◽

Therapy Resistance ◽

Parp Inhibitors ◽

Parp Inhibition ◽

Ovarian Cancer Cells ◽

Before And After ◽

Immunosuppressive Cytokine

Despite the promising activity of poly(ADP-ribose) polymerase (PARP) inhibitors (PARPi) in many cancer types with defects in the DNA damage response the majority of the treated patients acquire PARPi resistance and succumb to their diseases. Consequently, there is an urgent need to identify the mechanisms of PARPi resistance. Here, we show that PARPi treatment promotes STAT3 activation in ovarian cancer cells, tumor-associated immune cells and fibroblasts, resulting in PARPi resistance and immunosuppression. Comparison of ovarian cancer patient-matched tumor biopsies before and after PARPi therapy revealed that STAT3 activity was significantly higher in tumor cells and tumor-associated immune cells and fibroblasts post PARPi treatment. Moreover, one-time PARPi treatment activated STAT3 both in tumor cells as well as diverse immune subsets and fibroblasts. PARPi-treated immune cells exhibited decreased expression of immunostimulatory interferon (IFN)-γ and Granzyme B while increasing immunosuppressive cytokine IL-10. Finally, we demonstrate that the acquisition of PARPi resistance in ovarian cancer cells was accompanied by increased STAT3 activity. Ablating STAT3 inhibited PARPi-resistant ovarian tumor cell growth and/or restored PARPi sensitivity. Therefore, our study has identified a critical mechanism intrinsic to PARPi that promotes resistance to PARPi and induces immunosuppression during PARPi treatment by activating STAT3 in tumor cells and tumor-associated immune cells/fibroblasts.

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Single cell gene expression analysis of circulating tumor cells in ovarian cancer reveals CTCs co-expressing stem cell and mesenchymal markers

Geburtshilfe und Frauenheilkunde ◽

10.1055/s-0036-1592665 ◽

2016 ◽

Vol 76 (10) ◽

Cited By ~ 1

Author(s):

C Blassl ◽

JD Kuhlmann ◽

A Webers ◽

P Wimberger ◽

T Fehm ◽

...

Keyword(s):

Gene Expression ◽

Ovarian Cancer ◽

Stem Cell ◽

Single Cell ◽

Tumor Cells ◽

Circulating Tumor Cells ◽

Expression Analysis ◽

Gene Expression Analysis ◽

Cell Gene Expression ◽

Cell Gene

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RGD4C peptide mediates anti-p21Ras scFv entry into tumor cells and produces an inhibitory effect on the human colon cancer cell line SW480

BMC Cancer ◽

10.1186/s12885-021-08056-4 ◽

2021 ◽

Vol 21 (1) ◽

Cited By ~ 1

Author(s):

Chen-Chen Huang ◽

Fang-Rui Liu ◽

Qiang Feng ◽

Xin-Yan Pan ◽

Shu-Ling Song ◽

...

Keyword(s):

Antitumor Activity ◽

Cell Membrane ◽

Fusion Protein ◽

Tumor Cell ◽

Tumor Cells ◽

Fusion Proteins ◽

Inhibitory Effect ◽

Endosomal Escape ◽

Antitumor Effects ◽

Sw480 Cells

Abstract Background We prepared an anti-p21Ras scFv which could specifically bind with mutant and wild-type p21Ras. However, it cannot penetrate the cell membrane, which prevents it from binding to p21Ras in the cytoplasm. Here, the RGD4C peptide was used to mediate the scFv penetration into tumor cells and produce antitumor effects. Methods RGD4C-EGFP and RGD4C-p21Ras-scFv recombinant expression plasmids were constructed to express fusion proteins in E. coli, then the fusion proteins were purified with HisPur Ni-NTA. RGD4C-EGFP was used as reporter to test the factors affecting RGD4C penetration into tumor cell. The immunoreactivity of RGD4C-p21Ras-scFv toward p21Ras was identified by ELISA and western blotting. The ability of RGD4C-p21Ras-scFv to penetrate SW480 cells and colocalization with Ras protein was detected by immunocytochemistry and immunofluorescence. The antitumor activity of the RGD4C-p21Ras-scFv was assessed with the MTT, TUNEL, colony formation and cell migration assays. Chloroquine (CQ) was used an endosomal escape enhancing agent to enhance endosomal escape of RGD4C-scFv. Results RGD4C-p21Ras-scFv fusion protein were successfully expressed and purified. We found that the RGD4C fusion protein could penetrate into tumor cells, but the tumor cell entry of was time and concentration dependent. Endocytosis inhibitors and a low temperature inhibited RGD4C fusion protein endocytosis into cells. The change of the cell membrane potential did not affect penetrability. RGD4C-p21Ras-scFv could penetrate SW480 cells, effectively inhibit the growth, proliferation and migration of SW480 cells and promote this cells apoptosis. In addition, chloroquine (CQ) could increase endosomal escape and improve antitumor activity of RGD4C-scFv in SW480 cells. Conclusion The RGD4C peptide can mediate anti-p21Ras scFv entry into SW480 cells and produce an inhibitory effect, which indicates that RGD4C-p21Ras-scFv may be a potential therapeutic antibody for the treatment of ras-driven cancers.

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Tumour Versus Germline BRCA Testing in Ovarian Cancer: A Single-Site Institution Experience in the United Kingdom

Diagnostics ◽

10.3390/diagnostics11030547 ◽

2021 ◽

Vol 11 (3) ◽

pp. 547

Author(s):

Iolia Akaev ◽

Siavash Rahimi ◽

Olubukola Onifade ◽

Francis John Edward Gardner ◽

David Castells-Rufas ◽

...

Keyword(s):

Ovarian Cancer ◽

Unknown Origin ◽

Parp Inhibitors ◽

Serous Carcinoma ◽

High Grade ◽

Brca1 And Brca2 ◽

Brca Mutations ◽

Epithelial Cancers ◽

Pathogenic Variants ◽

Pathogenic Mutations

The aim of this audit was to evaluate the usefulness and serviceability of testing for pathogenic mutations in BRCA1 or BRCA2 (BRCA1/2) genes in ovarian cancer (OC) patients. One hundred and thirty-five patients with more common histological sub-types of OC were retrospectively identified between 2011 and 2019. The fail rate of the molecular analysis was 7.4% (10/135). One hundred and twenty-five records were evaluated: 99 (79.2%) patients had wild-type BRCA (both somatic and germline); tumour BRCA1/2 (tBRCA1/2) pathogenic mutations were found in 20 (16%) patients with distribution between BRCA1 and BRCA2 being 40% and 60%, respectively; 13 (10.4%) patients with pathogenic variants had germline mutations; and tBRCA1/2 with variant of unknown significance (VUS), in the absence of pathogenic BRCA1 or BRCA2 variants, was detected in 6 (4.8%) patients. Our data show that expanding the molecular service to the routine first-tumour testing for patients with OC will potentially increase the detection rate of BRCA mutations, thereby providing early benefits of PARP inhibitors therapy. The tumour testing service should continue to be offered to newly diagnosed patients with high-grade epithelial cancers, including high-grade serous carcinoma, but also with carcinosarcomas and poorly-differentiated metastatic adenocarcinomas of unknown origin.

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Differences in PARP Inhibitors for the Treatment of Ovarian Cancer: Mechanisms of Action, Pharmacology, Safety, and Efficacy

International Journal of Molecular Sciences ◽

10.3390/ijms22084203 ◽

2021 ◽

Vol 22 (8) ◽

pp. 4203

Author(s):

Giorgio Valabrega ◽

Giulia Scotto ◽

Valentina Tuninetti ◽

Arianna Pani ◽

Francesco Scaglione

Keyword(s):

Ovarian Cancer ◽

Signal Transduction ◽

Dna Damage ◽

Chemical Structure ◽

Parp Inhibitors ◽

Mechanisms Of Action ◽

Point Of View ◽

Safety And Efficacy ◽

Damage Repair ◽

Pharmacokinetic Properties

Poly(ADP-ribose) polymerases (PARP) are proteins responsible for DNA damage detection and signal transduction. PARP inhibitors (PARPi) are able to interact with the binding site for PARP cofactor (NAD+) and trapping PARP on the DNA. In this way, they inhibit single-strand DNA damage repair. These drugs have been approved in recent years for the treatment of ovarian cancer. Although they share some similarities, from the point of view of the chemical structure and pharmacodynamic, pharmacokinetic properties, these drugs also have some substantial differences. These differences may underlie the different safety profiles and activity of PARPi.

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Calreticulin—Multifunctional Chaperone in Immunogenic Cell Death: Potential Significance as a Prognostic Biomarker in Ovarian Cancer Patients

Cells ◽

10.3390/cells10010130 ◽

2021 ◽

Vol 10 (1) ◽

pp. 130

Author(s):

Michal Kielbik ◽

Izabela Szulc-Kielbik ◽

Magdalena Klink

Keyword(s):

Ovarian Cancer ◽

Cell Death ◽

Cancer Patients ◽

Tumor Cells ◽

Cytotoxic T Cells ◽

Adaptive Immune Response ◽

Ovarian Cancer Cells ◽

Immunogenic Cell Death ◽

Antigen Presenting ◽

Molecular Patterns

Immunogenic cell death (ICD) is a type of death, which has the hallmarks of necroptosis and apoptosis, and is best characterized in malignant diseases. Chemotherapeutics, radiotherapy and photodynamic therapy induce intracellular stress response pathways in tumor cells, leading to a secretion of various factors belonging to a family of damage-associated molecular patterns molecules, capable of inducing the adaptive immune response. One of them is calreticulin (CRT), an endoplasmic reticulum-associated chaperone. Its presence on the surface of dying tumor cells serves as an “eat me” signal for antigen presenting cells (APC). Engulfment of tumor cells by APCs results in the presentation of tumor’s antigens to cytotoxic T-cells and production of cytokines/chemokines, which activate immune cells responsible for tumor cells killing. Thus, the development of ICD and the expression of CRT can help standard therapy to eradicate tumor cells. Here, we review the physiological functions of CRT and its involvement in the ICD appearance in malignant disease. Moreover, we also focus on the ability of various anti-cancer drugs to induce expression of surface CRT on ovarian cancer cells. The second aim of this work is to discuss and summarize the prognostic/predictive value of CRT in ovarian cancer patients.

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