scholarly journals The Complement System in Ovarian Cancer: An Underexplored Old Path

Cancers ◽  
2021 ◽  
Vol 13 (15) ◽  
pp. 3806
Author(s):  
Yaiza Senent ◽  
Daniel Ajona ◽  
Antonio González-Martín ◽  
Ruben Pio ◽  
Beatriz Tavira

Ovarian cancer is one of the most lethal gynecological cancers. Current therapeutic strategies allow temporary control of the disease, but most patients develop resistance to treatment. Moreover, although successful in a range of solid tumors, immunotherapy has yielded only modest results in ovarian cancer. Emerging evidence underscores the relevance of the components of innate and adaptive immunity in ovarian cancer progression and response to treatment. Particularly, over the last decade, the complement system, a pillar of innate immunity, has emerged as a major regulator of the tumor microenvironment in cancer immunity. Tumor-associated complement activation may support chronic inflammation, promote an immunosuppressive microenvironment, induce angiogenesis, and activate cancer-related signaling pathways. Recent insights suggest an important role of complement effectors, such as C1q or anaphylatoxins C3a and C5a, and their receptors C3aR and C5aR1 in ovarian cancer progression. Nevertheless, the implication of these factors in different clinical contexts is still poorly understood. Detailed knowledge of the interplay between ovarian cancer cells and complement is required to develop new immunotherapy combinations and biomarkers. In this context, we discuss the possibility of targeting complement to overcome some of the hurdles encountered in the treatment of ovarian cancer.

Blood ◽  
2018 ◽  
Vol 132 (Supplement 1) ◽  
pp. 4970-4970
Author(s):  
Omayra Gonzalez Pagan ◽  
Min Soon Cho ◽  
Vahid Afshar-Kharghan

Abstract Platelets promote metastasis and growth of ovarian cancer. We have shown that platelets extravasate into the tumor microenvironment (TME) and increase proliferation and epithelial-mesenchymal transition (EMT) in ovarian cancer cells. We have also shown that activation of the complement system in TME of ovarian cancer enhances tumor growth. Ovarian cancer cells secrete complement proteins that upon activation in the TME increase proliferation of cancer cells and promote EMT via an autocrine pathway. The activators of the complement system in the TME have not been identified. We have demonstrated that upon activation platelets activate the complement system on their surface. In the current study, we examined whether extravasated platelets inside tumors contribute to the complement activation in the TME. 1) We examined the effect of antiplatelet reagents on platelet extravasation into TME, using murine models of ovarian cancer. Tumors induced by injection of ovarian cancer cells into the peritoneum of Nu/Nu mice were resected after 6-8 weeks and the number of extravasated platelets was determined by immunostaining tumor sections and counting the number CD42 (GPIb) positive cells that were outside the blood vessels (CD31 positive). We found that platelet extravasation is an active process and platelet inhibition by aspirin or ticagrelor reduces the number of extravasated platelets. Furthermore, P2Y12 deficient platelets extravasate less than normal platelets. In all of these experiments, the number of extravasated red blood cells were significantly less than extravasated platelets and was not affected by the inhibition of platelets. 2) We examined the effect of platelet inhibition on the activation of the complement system in the TME. We immunostained resected tumors from aspirin- or ticagrelor-treated tumor-bearingmice and from P2Y12-deficient tumor-bearingmice for the endproductof complement activation (C5b-9 or membrane attack complex). Inhibition of platelet function by aspirin or ticagrelor,or the presence of hypoactive platelets in P2Y12 deficient mice reduced the amount of C5b-9 deposited in the tumors induced in murine models of ovarian cancer. Our result showed that complement activation in the TME is at least partially dependent onextravasated platelets. We propose that platelets in addition to directly increasing proliferation of ovarian cancer cells, also enhance tumor growth by activating the complement system in the vicinity of cancer cells. Our study links platelets, complement activation, and ovarian cancer growth; and raises the possibility of using antiplatelet reagents and complement inhibitors as novel synergisticanti-tumor reagents in ovarian cancer. Disclosures No relevant conflicts of interest to declare.


Medicina ◽  
2021 ◽  
Vol 57 (5) ◽  
pp. 456
Author(s):  
Umamaheswari Natarajan ◽  
Thiagarajan Venkatesan ◽  
Appu Rathinavelu

Background andObjective: Epigenetic modifications are believed to play a significant role in the development of cancer progression, growth, differentiation, and cell death. One of the most popular histone deacetylases inhibitors (HDACIs), suberoylanilide hydroxamic acid (SAHA), also known as Vorinostat, can directly activate p21WAF1/CIP1 gene transcription through hyperacetylation of histones by a p53 independent mechanism. In the present investigation, we evaluated the correlation between histone modifications and DNA methyltransferase enzyme levels following SAHA treatments in A2780 ovarian cancer cells. Materials and Methods: Acetylation of histones and methyltransferases levels were analyzed using RT2 profiler PCR array, immunoblotting, and immunofluorescence methods in 2D and 3D cell culture systems. Results: The inhibition of histone deacetylases (HDAC) activities by SAHA can reduce DNA methyl transferases / histone methyl transferases (DNMTs/HMTs) levels through induction of hyperacetylation of histones. Immunofluorescence analysis of cells growing in monolayers and spheroids revealed significant up-regulation of histone acetylation preceding the above-described changes. Conclusions: Our results depict an interesting interplay between histone hyperacetylation and a decrease in methyltransferase levels in ovarian cancer cells, which may have a positive impact on the overall outcomes of cancer treatment.


Cancers ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 3388
Author(s):  
Mona Alharbi ◽  
Andrew Lai ◽  
Shayna Sharma ◽  
Priyakshi Kalita-de Croft ◽  
Nihar Godbole ◽  
...  

Hypoxia is a key regulator of cancer progression and chemoresistance. Ambiguity remains about how cancer cells adapt to hypoxic microenvironments and transfer oncogenic factors to surrounding cells. In this study, we determined the effects of hypoxia on the bioactivity of sEVs in a panel of ovarian cancer (OvCar) cell lines. The data obtained demonstrate a varying degree of platinum resistance induced in OvCar cells when exposed to low oxygen tension (1% oxygen). Using quantitative mass spectrometry (Sequential Window Acquisition of All Theoretical Fragment Ion Mass Spectra, SWATH) and targeted multiple reaction monitoring (MRM), we identified a suite of proteins associated with glycolysis that change under hypoxic conditions in cells and sEVs. Interestingly, we identified a differential response to hypoxia in the OvCar cell lines and their secreted sEVs, highlighting the cells’ heterogeneity. Proteins are involved in metabolic reprogramming such as glycolysis, including putative hexokinase (HK), UDP-glucuronosyltransferase 1–6 (UD16), and 6-phosphogluconolactonase (6 PGL), and their presence correlates with the induction of platinum resistance. Furthermore, when normoxic cells were exposed to sEVs from hypoxic cells, platinum-resistance increased significantly (p < 0.05). Altered chemoresistance was associated with changes in glycolysis and fatty acid synthesis. Finally, sEVs isolated from a clinical cohort (n = 31) were also found to be enriched in glycolysis-pathway proteins, especially in patients with recurrent disease. These data support the hypothesis that hypoxia induces changes in sEVs composition and bioactivity that confers carboplatin resistance on target cells. Furthermore, we propose that the expression of sEV-associated glycolysis-pathway proteins is predictive of ovarian cancer recurrence and is of clinical utility in disease management.


2019 ◽  
Author(s):  
Yuqiu Li ◽  
Linpei Zhang ◽  
Wenshu Meng ◽  
Youhe Gao

AbstractOvarian cancer is the most lethal gynecological malignancy in women, and it is likely to metastasize and has a poor prognosis. The early and reliable diagnosis and monitoring of ovarian cancer is very important. Without a homeostasis mechanism, urine can reflect early systemic changes in the body and has a great potential to be used for the early detection of cancer. This study tested whether early changes could be detected in two ovarian cancer rat models. Two rat models were established by either intraperitoneal (i.p.) or orthotopic (o.t.) injection of NuTu-19 ovarian cancer cells in female Fischer344 rats. Urine samples from ovarian cancer rats were collected at five time points during cancer development, and urinary proteins from the rats were profiled by liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). Compared with pre-injection samples, 49 differential proteins that have human orthologues were significantly changed in the orthotopically injected model. Among them, 24 of the differential proteins have previously been reported to be associated with ovarian cancer, six of which were reported to be biomarkers of ovarian cancer. On the 7th day after orthotopic injection, four differential proteins (APOA1, OX2G, CHMP5, HEXB) were identified before obvious metastases appeared. In the intraperitoneal injection model, 76 differential proteins were changed during the course of ovarian cancer development. The results show that urine proteins could enable the early detection and monitoring of ovarian cancer progression and could lay a foundation for further exploration of the biomarkers of ovarian cancer.


2018 ◽  
Vol 49 (5) ◽  
pp. 1766-1777 ◽  
Author(s):  
Jie Li ◽  
Songlin Zhang ◽  
Meili Pei ◽  
Lei Wu ◽  
Yanli Liu ◽  
...  

Background/Aims: Epithelial-mesenchymal transition (EMT) is one of the key mechanisms mediating cancer progression. Snail1 has a pivotal role in the regulation of EMT, involving the loss of E-cadherin and concomitant upregulation of vimentin, among other biomarkers. We have found FSCN1 promoted EMT in ovarian cancer cells, but the precise mechanism of FSCN1 in EMT process has not been clearly elucidated. Methods: The levels of FSCN1 and snail1 were determined in epithelial ovarian cancer(EOC) specimen and in ovarian cancer cells by RT-qPCR. The changes of EMT makers and effects on snail1 by FSCN1 were examined by overexpression or depletion of FSCN1 in EOC cells by RT-qPCR and western blotting. The invasiveness of the FSCN1-modified EOC cells was examined in transwell assay. Co-immunoprecipitation (IP) was performed to detect the interaction between snail1 and FSCN1 in EOC cells. Results: We found FSCN1 and snail1 significantly increased in EOC, and especially in EOC with metastasis. FSCN1 was positively correlated with snail1 expression at the cellular/histological levels. Moreover, we further showed that FSCN1 physiologically interacted with and increased the levels of snail1 to promote ovarian cancer cell EMT. Conclusion: FSCN1 promote EMT through snail1 in ovarian cancer cells. FSCN1 is an attractive novel target for inhibiting invasion and metastasis of EOC cells.


2020 ◽  
Author(s):  
Nan Zhang ◽  
Yue Jin ◽  
Qiubo Hu ◽  
Shanshan Cheng ◽  
Chao Wang ◽  
...  

Abstract Background: Increasing researches have demonstrated the critical functions of circular RNAs (circRNAs) in the progression of malignant tumors, including ovarian cancer. In this study, we aim to investigate abnormally expression of hsa_circ_0078607 and the role of hsa_circ_0078607 during ovarian cancer pathogenesis.Methods: RT-PCR were used to detect the expression of circ_0078607 in ovarian cancer tissues. To determine the functional roles of circ_0078607 in ovarian cancer, cell proliferation and cell invasion assays were performed. Bioinformatics and luciferase reporter analysis were used to predict the target of circ_0078607.Results: In the present study, we first found that circ_0078607 was downregulated in ovarian cancer. Forced circ_0078607 expression significantly suppressed proliferation and promotes apoptosis of ovarian cancer cells. Mechanically, bioinformatics and luciferase reporter analysis identified that miR-518a-5p as a direct target of circ_0078607, while Fas as a direct target of miR-518a-5p. MiR-518a-5p negatively regulates Fas in ovarian cancer cells, while overexpression of circ_0078607 could increase the expression of Fas inhibited by miR-518a-5p. Furthermore, overexpression of circ_0078607 could inhibit the proliferation and invasion of ovarian cancer cells caused by miR-518a-5p mimic.Conclusion: The results of the present study revealed that circ_0078607 suppresses ovarian cancer progression by sponging oncogenic miR-518a-5p to induce Fas expression, which may provide new therapeutic approach for ovarian cancer.


BMC Cancer ◽  
2020 ◽  
Vol 20 (1) ◽  
Author(s):  
Ruth M. Escalona ◽  
Maree Bilandzic ◽  
Patrick Western ◽  
Elif Kadife ◽  
George Kannourakis ◽  
...  

Abstract Background The metzincin family of metalloproteinases and the tissue inhibitors of metalloproteinases (TIMPs) are essential proteins required for biological processes during cancer progression. This study aimed to determine the role of TIMP-2 in ovarian cancer progression and chemoresistance by reducing TIMP-2 expression in vitro in Fallopian tube secretory epithelial (FT282) and ovarian cancer (JHOS2 and OVCAR4) cell lines. Methods FT282, JHOS2 and OVCAR4 cells were transiently transfected with either single or pooled TIMP-2 siRNAs. The expression of different genes after TIMP-2 knock down (T2-KD) or in response to chemotherapy was determined at the mRNA level by quantitative real time PCR (qRT-PCR) and at the protein level by immunofluorescence. Sensitivity of the cell lines in response to chemotherapy after TIMP-2 knock down was investigated by 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) and 5-Ethynyl-2′-deoxyuridine (EdU) assays. Cell invasion in response to TIMP-2 knockdown was determined by xCELLigence. Results Sixty to 90 % knock down of TIMP-2 expression was confirmed in FT282, OVCAR4 and JHOS2 cell lines at the mRNA and protein levels. TIMP-2 knock down did not change the mRNA expression of TIMP-1 or TIMP-3. However, a significant downregulation of MMP-2 in T2-KD cells occurred at both the protein and activation levels, compared to Control (Cont; scrambled siRNA) and Parental cells (P, transfection reagent only). In contrast, membrane bound MT1-MMP protein levels were significantly upregulated in T2-KD compared to Cont and P cells. T2-KD cells exhibited enhanced proliferation and increased sensitivity to cisplatin and paclitaxel treatments. Enhanced invasion was observed in the T2-KD-JOSH2 and OVCAR4 cells but not in T2-KD-FT282 cells. Treatment with cisplatin or paclitaxel significantly elevated the expression of TIMP-2 in Cont cells but not in T2-KD cells, consistent with significantly elevated expression of chemoresistance and CSC markers and activation of STAT3. Furthermore, a potent inhibitor of STAT3 activation, Momelotinib, suppressed chemotherapy-induced activation of P-STAT3 in OVCAR4 cells with concomitant reductions in the expression of chemoresistance genes and CSC markers. Conclusions The above results suggest that TIMP-2 may have a novel role in ovarian cancer proliferation, invasion and chemoresistance.


1999 ◽  
Vol 29 (8) ◽  
pp. 653-656 ◽  
Author(s):  
Esterbauer ◽  
Krempler ◽  
Oberkofler ◽  
Patsch

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