Peritoneal and Subperitoneal Stroma May Facilitate Regional Spread of Ovarian Cancer

Leader cells promote immunosuppression to drive ovarian cancer progression in vivo

Over 75% of patients with ovarian cancer present with late-stage disease, often accompanied by extensive metastasis. The metastatic cascade is driven by a sub-population of transcriptionally plastic cells known as "leader cells" (LCs), which play a critical role in collective invasion yet remain poorly understood. LCs are marked by the expression of keratin-14 (KRT14), which determines their migratory and invasive capacity in ovarian cancer. This study demonstrates that KRT14+ LCs promote tumor progression through immunosuppression and immune privilege in vivo. In the ID8 syngeneic epithelial ovarian cancer mouse model, tumor-specific loss of KRT14+ LCs impairs tumor progression and metastatic spread without affecting cellular proliferation. Immune profiling shows reduced immunosuppressive regulatory T cells (Tregs) and M2 macrophages and improved CD8+ T cell/Treg ratios in LC knockout (LCKO) mice. Conversely, forced LC overexpression accelerates metastasis and increases the secretion of immunosuppressive chemokines, such as CCL22 and CCL5, highlighting the role of KRT14+ LCs in immune suppression and metastatic progression.

Long Non-Coding RNAs: Bridging Cancer-Associated Thrombosis and Clinical Outcome of Ovarian Cancer Patients

Ovarian cancer (OC) and venous thromboembolism (VTE) have a close relationship, in which tumour cells surpass the haemostatic system to drive cancer progression. Long non-coding RNAs (lncRNAs) have been implicated in VTE pathogenesis, yet their roles in cancer-associated thrombosis (CAT) and their prognostic value are unexplored. Understanding how these lncRNAs influence venous thrombogenesis and ovarian tumorigenesis may lead to the identification of valuable biomarkers for VTE and OC management. Thus, this study evaluated the impact of five lncRNAs, namely MALAT1, TUG1, NEAT1, XIST and MEG8, on a cohort of 40 OC patients. Patients who developed VTE after OC diagnosis had worse overall survival compared to their counterparts (log-rank test, p = 0.028). Elevated pre-chemotherapy MEG8 levels in peripheral blood cells (PBCs) predicted VTE after OC diagnosis (Mann-Whitney U test, p = 0.037; Χ2 test, p = 0.033). In opposition, its low levels were linked to a higher risk of OC progression (adjusted hazard ratio (aHR) = 3.00; p = 0.039). Furthermore, low pre-chemotherapy NEAT1 levels in PBCs were associated with a higher risk of death (aHR = 6.25; p = 0.008). As for the remaining lncRNAs, no significant association with VTE incidence, OC progression or related mortality was observed. Future investigation with external validation in larger cohorts is needed to dissect the implications of the evaluated lncRNAs in OC patients.

Proteome profiling of ductal carcinoma in situ

BACKGROUND AND AIM

DCIS is the most common type of non-invasive breast cancer, accounting for about 15 to 30%. Proteome profile is used to detect biomarkers in the tissues of breast cancer patients by mass spectrometry. This study aimed to obtain the expression profile of DCIS proteome, and the expression profile of invasive biomarkers, and finally to introduce a dedicated biomarker panel to facilitate the prognosis and early detection for in situ breast cancer patients.

METHODS AND MATERIALS

In this study, 10 patients with breast cancer (DCIS) were studied. Benign (marginal) and cancerous tissue samples were obtained from patients for proteomics experiments. Initially, all tissue proteins were extracted using standard methods, and the proteins were separated using two-dimensional electrophoresis. Then, the expression amount of the extracted proteins was determined by ITRAQ. The data were analysed by R software, and gene ontology was utilised for describing the protein in detail.

RESULTS

30 spots on gel electrophoresis were found in the tumor tissue group (sample), and 15 spots in the margin group (control) with P < 0.05. Healthy and cancerous tissue gels showed that 5 spots had different expression. VWF, MMP9, ITGAM, MPO and PLG protein spots were identified using the site www.ebi.ac.uk/IPI. Finally, protein biomarkers for breast tumor tissue with margin were introduced with the names of P04406, P49915, P05323, P06733, and P02768.

DISCUSSION

There are 5 critical proteins in inducing cancer pathways especially complement and coagulation cascades. The hall markers of a healthy cell to be cancerous are proliferation, invasion, angiogenesis, and changes in the immune system. Hence, regulation of protein plays a key role in developing recurrence to breast cancer in margins.

The tumor immune microenvironment in peritoneal carcinomatosis

One in four patients with colorectal cancer, 40% of gastric cancer patients, and 60% of ovarian cancer patients will develop peritoneal metastases (PM) in the course of their disease. The outcome of patients with widespread PM remains poor with currently available treatments. Despite the relatively common occurrence of PM, little is known on the pathophysiology that drives the peritoneal metastatic cascade. It is increasingly recognized that the stromal components of the peritoneal microenvironment play an essential role in tumor progression. However, little is known about the specific interactions and components of the peritoneal tumor microenvironment, particularly with respect the immune cell population. We summarize the current knowledge of the tumor immune microenvironment (TIME) in peritoneal metastases originating from the three most common origins: ovarian, gastric, and colorectal cancer. Clearly, the TIME is highly heterogeneous and its composition and functional activity differ according to tumor type and, within the same patient, according to anatomical location. The TIME in PM remains to be explored in detail, and further elucidation of their immune contexture may allow biology driven design of novel immune modulating or immune targeting therapies.

The versatile role of the contact system in cardiovascular disease, inflammation, sepsis and cancer

The human contact system consists of plasma proteins, which - after contact to foreign surfaces - are bound to them, thereby activating the zymogens of the system into enzymes. This activation mechanism gave the system its name - contact system. It is considered as a procoagulant and proinflammatory response mechanism, as activation finally leads to the generation of fibrin and bradykinin. To date, no physiological processes have been described that are mediated by contact activation. However, contact system factors play a pathophysiological role in numerous diseases, such as cardiovascular diseases, arthritis, colitis, sepsis, and cancer. Contact system factors are therefore an interesting target for new therapeutic options in different clinical conditions.

The Role of Stroma in Ovarian Cancer

Background: Ovarian cancer is one of the gynecological malignancies responsible for thousands of deaths in women worldwide. Malignant solid tumors are formed by malignant cells and stroma that influence each other, where different types of cells in the stromal environment can be recruited by malignant cells to promote tumor growth and facilitate metastasis. The chronic inflammatory response is increasingly accepted in its relation to the pathophysiology of the onset and development of tumors, sustained cell proliferation in an environment rich in inflammatory cells, growth factors, activated stroma and DNA damage agents may increase the risk to develop a neoplasm.Methods: A search for the following keywords was performed in the PubMed database; "Ovarian cancer", "stroma", "tumor-associated macrophages", "cancer-associated fibroblasts", "cytokines", "angiogenesis", "epithelial-mesenchymal transition", and "extracellular matrix".Results: The articles identified were published in English between 1971 and 2018. A total of 154 articles were selected for further analysis. Conclusion: We consider ovarian cancer as a heterogeneous disease, not only in the sense that different histological or molecular subtypes may be behind the same clinical result, but also that multiple cell types besides cancer cells, like other non-cellular components, need to be mobilized and coordinated to support tumor survival, growth, invasion and progression.

Roles of Factor XII in Innate Immunity

Factor XII (FXII) is the zymogen of serine protease, factor XIIa (FXIIa). FXIIa enzymatic activities have been extensively studied and FXIIa inhibition is emerging as a promising target to treat or prevent thrombosis without creating a hemostatic defect. FXII and plasma prekallikrein reciprocally activate each other and result in liberation of bradykinin. Due to its unique structure among coagulation factors, FXII exerts mitogenic activity in endothelial and smooth muscle cells, indicating that zymogen FXII has activities independent of its protease function. A growing body of evidence has revealed that both FXII and FXIIa upregulate neutrophil functions, contribute to macrophage polarization and induce T-cell differentiation. In vivo, these signaling activities contribute to host defense against pathogens, mediate the development of neuroinflammation, influence wound repair and may facilitate cancer maintenance and progression. Here, we review the roles of FXII in innate immunity as they relate to non-sterile and sterile immune responses.

The mechanical microenvironment regulates ovarian cancer cell morphology, migration, and spheroid disaggregation

There is growing appreciation of the importance of the mechanical properties of the tumor microenvironment on disease progression. However, the role of extracellular matrix (ECM) stiffness and cellular mechanotransduction in epithelial ovarian cancer (EOC) is largely unknown. Here, we investigated the effect of substrate rigidity on various aspects of SKOV3 human EOC cell morphology and migration. Young’s modulus values of normal mouse peritoneum, a principal target tissue for EOC metastasis, were determined by atomic force microscopy (AFM) and hydrogels were fabricated to mimic these values. We find that cell spreading, focal adhesion formation, myosin light chain phosphorylation, and cellular traction forces all increase on stiffer matrices. Substrate rigidity also positively regulates random cell migration and, importantly, directional increases in matrix tension promote SKOV3 cell durotaxis. Matrix rigidity also promotes nuclear translocation of YAP1, an oncogenic transcription factor associated with aggressive metastatic EOC. Furthermore, disaggregation of multicellular EOC spheroids, a behavior associated with dissemination and metastasis, is enhanced by matrix stiffness through a mechanotransduction pathway involving ROCK, actomyosin contractility, and FAK. Finally, this pattern of mechanosensitivity is maintained in highly metastatic SKOV3ip.1 cells. These results establish that the mechanical properties of the tumor microenvironment may play a role in EOC metastasis.

Subventricular zone involvement in Glioblastoma - A proteomic evaluation and clinicoradiological correlation

Glioblastoma multiforme (GBM), the most malignant of all gliomas is characterized by a high degree of heterogeneity and poor response to treatment. The sub-ventricular zone (SVZ) is the major site of neurogenesis in the brain and is rich in neural stem cells. Based on the proximity of the GBM tumors to the SVZ, the tumors can be further classified into SVZ+ and SVZ−. The tumors located in close contact with the SVZ are classified as SVZ+, while the tumors located distantly from the SVZ are classified as SVZ−. To gain an insight into the increased aggressiveness of SVZ+ over SVZ− tumors, we have used proteomics techniques like 2D-DIGE and LC-MS/MS to investigate any possible proteomic differences between the two subtypes. Serum proteomic analysis revealed significant alterations of various acute phase proteins and lipid carrying proteins, while tissue proteomic analysis revealed significant alterations in cytoskeletal, lipid binding, chaperone and cell cycle regulating proteins, which are already known to be associated with disease pathobiology. These findings provide cues to molecular basis behind increased aggressiveness of SVZ+ GBM tumors over SVZ− GBM tumors and plausible therapeutic targets to improve treatment modalities for these highly invasive tumors.

Reciprocal links between venous thromboembolism, coagulation factors and ovarian cancer progression

Ovarian cancer is the most lethal gynecological malignancy, which is due to late presentation. Treating advanced stage ovarian cancer is difficult, and tumor recurrence and chemoresistance frequently occur. In addition, early detection remains a major challenge as there are no early warning signs and no appropriate biomarkers. To reduce mortality rates of ovarian cancer patients, novel drug targets and biomarkers are needed. We postulate that hemostatic keyplayers are of importance when combatting ovarian cancer. The majority of ovarian cancer patients have abnormal hemostatic blood serum marker levels, which indicate an activated coagulation system. This makes patients more prone to experiencing venous thromboembolism (VTE), and the occurrence of VTE in ovarian cancer patients adversely affects survival. Coagulation activation also promotes tumor progression as it influences tumor biology at several stages and the decreased survival rates associated with ovarian cancer-associated thrombosis are more likely due to cancer metastasis rather than to fatal thromboembolic events. In this review, we will discuss; (1) Population studies that address the bidirectional relationship between VTE and ovarian cancer, and the most important risk factors involved; (2) The mechanisms of coagulation factors and platelets that are critically involved in the development of VTE, and the progression of ovarian cancer; (3) Roles and future directions of coagulation factors in ovarian cancer therapy, and in diagnosis and prognosis of ovarian cancer as biomarkers.

Targeting ILK and β4 integrin abrogates the invasive potential of ovarian cancer

Integrins and integrin-linked kinase (ILK) are essential to cancerous invasion because they mediate physical interactions with the extracellular matrix, and regulate oncogenic signaling pathways. The purpose of our study is to determine whether deletion of β1 and β4 integrin and ILK, alone or in combination, has antitumoral effects in ovarian cancer. Expression of β1 and β4 integrin and ILK was analyzed by immunohistochemistry in 196 ovarian cancer tissue samples. We assessed the effects of depleting these molecules with shRNAs in ovarian cancer cells by Western blot, conventional RT-PCR, cell proliferation, migration, invasion, and in vitro Rac1 activity assays, and in vivo xenograft formation assays. Overexpression of β4 integrin and ILK in human ovarian cancer specimens was found to correlate with tumor aggressiveness. Depletion of these targets efficiently suppresses ovarian cancer cell proliferation, migration, and invasion in vitro and xenograft tumor formation in vivo. We also demonstrated that single depletion of ILK or combination depletion of β4 integrin/ILK inhibits phosphorylation of downstream signaling targets, p-Ser 473 Akt and p-Thr202/Tyr204 Erk1/2, and activation of Rac1, as well as reduce expression of MMP-2 and MMP-9 and increase expression of caspase-3 in vitro. In conclusion, targeting β4 integrin combined with ILK can instigate the latent tumorigenic potential and abrogate the invasive potential in ovarian cancer.