Potential Role of Microfibrillar-Associated Protein 4, Fibrotic Indices and Oxidative Stress in Hepatocellular Carcinoma

Role and new insights of microfibrillar-associated protein 4 in fibrotic diseases

Fibrosis is one of the most worrisome complications of chronic inflammatory diseases, leading to tissue damage, organ failure, and ultimately, death. The most notable pathological characteristic of fibrosis is the excessive accumulation of extracellular matrix (ECM) components such as collagen and fibronectin adjacent to foci of inflammation or damage. The human microfibrillar-associated protein 4 (MFAP4), an important member of the superfamily of fibrinogen-related proteins, is considered to have an extremely important role in ECM transformation of fibrogenesis. This review summarizes the structure, characteristics, and physiological functions of MFAP4 and the importance of MFAP4 in various fibrotic diseases. Meanwhile, we elaborated the underlying actions and mechanisms of MFAP4 in the development of fibrosis, suggesting that a better understand of MFAP4 broadens novel perspective for early screening, diagnosis, prognostic risk assessment, and treatment of fibrotic diseases.

MFAP4-Mediated Effects in Elastic Fiber Homeostasis, Integrin Signaling and Cancer, and Its Role in Teleost Fish

Microfibrillar-associated protein 4 (MFAP4) is an extracellular matrix (ECM) protein belonging to the fibrinogen-related domain superfamily. MFAP4 is highly expressed in elastin-rich tissues such as lung, blood vessels and skin. MFAP4 is involved in organization of the ECM, regulating proper elastic fiber assembly. On the other hand, during pathology MFAP4 actively contributes to disease development and progression due to its interactions with RGD-dependent integrin receptors. Both tissue expression and circulating MFAP4 levels are associated with various disorders, including liver fibrosis and cancer. In other experimental models, such as teleost fish, MFAP4 appears to participate in host defense as a macrophage-specific innate immune molecule. The aim of this review is to summarize the accumulating evidence that indicates the importance of MFAP4 in homeostasis as well as pathological conditions, discuss its known biological functions with special focus on elastic fiber assembly, integrin signaling and cancer, as well as describe the reported functions of non-mammalian MFAP4 in fish. Overall, our work provides a comprehensive overview on the role of MFAP4 in health and disease.

Coenzyme Q10 attenuates rat hepatocarcinogenesis via the reduction of CD59 expression and phospholipase D activity

The current study aimed to test the profile of serum lipids, phospholipase D (PLD) activity, and CD59 expression pattern in rat hepatocellular carcinoma (HCC) after therapeutic treatment with Coenzyme Q10 (CoQ10). Three rat groups were allocated as normal control, untreated HCC, and treated HCC (HCC + CoQ10). The levels of serum α-fetoprotein (AFP) and tumour necrosis factor (TNF)-α were assessed using enzyme-linked immunosorbent assay (ELISA), while proliferating cell nuclear antigen (PCNA) was detected using immunohistochemistry (IHC). Serum lipids, classical (CH50), and alternative (APH50) pathways of complement activation, the liver cell HMG-CoA reductase (HMGCR), and PLD activities were assayed colorimetrically. The protein expression of CD59, scavenger receptor class B type 1 (SRB1), B cell lymphoma-2 (Bcl2), and cleaved Caspase-3 (Casp-3) were detected using western blotting, while the level of serum CD59 (sCD59) was assessed using dot-blot. CoQ10 reduced the cell proliferation, histological alterations, and the levels of AFP and TNF-α but increased lipids, CH50, and sCD59 in serum. In the liver cell, CoQ10 decreased and increased PLD and HMGCR enzyme activities, respectively. In addition, reduction of liver CD59, Bcl2, and SRB1 vs increased cleaved Casp-3 expressions was observed. Statistical correlation indicated an inverse relationship between CH50 and each of CD59 expression and PLD activity after treatment with CoQ10. In conclusion, CoQ10 could protect against rat HCC through increased lipids and the reduction of CD59 expression and PLD activity. SIGNIFICANCE OF THE STUDY: To our knowledge, this study is the first to describe the attenuating effect of antitumour natural product like Coenzyme Q10 (CoQ10) via the reduction of CD59 expression and phospholipase D (PLD) activity. This illustrates the important role of CD59 and PLD in relation to lipids in cancer prevention.