HtrA1 as a promising tissue marker in cancer: a meta-analysis

Current look at the most promising proteomic and glycomic biomarkers of bladder cancer

BACKGROUND

Bladder cancer (BC) belongs to the most frequent cancer types. The diagnostic process is still long and costly, with a high percentage of false-positive or -negative results. Due to the cost and lack of effectiveness, older methods need to be supplemented or replaced by a newer more reliable method. In this regard, proteins and glycoproteins pose high potential.

METHODS

We performed an online search in PubMed/Medline, Scopus, and Web of Science databases to find relevant studies published in English up until May 2023. If applicable, we set the AUC threshold to 0.90 and sensitivity/specificity (SN/SP) to 90%.

FINDINGS

Protein and glycoprotein biomarkers are a demonstrably viable option in BC diagnostics. Cholinesterase shows promise in progression-free survival. BLCA-4, ORM-1 along with HTRA1 in the detection of BC. Matrix metallopeptidase 9 exhibits potential for stratification of muscle-invasive subtypes with high negative predictive value for aggressive phenotypes. Distinguishing non-muscle invasive subtypes benefits from Keratin 17. Neu5Gc-modified UMOD glycoproteins pose potential in BC diagnosis, while fibronectin, laminin-5, collagen type IV, and lamprey immunity protein in early detection of BC.

Carfilzomib relieves pancreatitis-initiated pancreatic ductal adenocarcinoma by inhibiting high-temperature requirement protein A1

Pancreatitis is a crucial risk factor for pancreatic ductal adenocarcinoma (PDAC), and our previous study had proved high-temperature requirement protein A1 (HTRA1) exacerbates pancreatitis insult; however, the function and mechanism of HTRA1 in pancreatitis-initiated PDAC is still unclear. In the present paper, we clarified the expression of HTRA1 in PDAC using bioinformatics and immunohistochemistry of tissue chip, and found that HTRA1 is significantly upregulated in PDAC. Moreover, the proliferation, migration, invasion and adhesion of PANC-1 and SW1990 cells were promoted by overexpression of HTRA1, but inhibited by knockdown of HTRA1. Meanwhile, we found that HTRA1 arrested PANC-1 and SW1990 cells at G2/M phase. Mechanistically, HTRA1 interacted with CDK1 protein, and CDK1 inhibitor reversed the malignant phenotype of PANC-1 and pancreatitis-initiated PDAC activated by HTRA1 overexpression. Finally, we discovered a small molecule drug that can inhibit HTRA1, carfilzomib, which has been proven to inhibit the biological functions of tumor cells in vitro and intercept the progression of pancreatitis-initiated PDAC in vivo. In conclusion, the activation of HTRA1-CDK1 pathway promotes the malignant phenotype of tumor cells by blocking the cell cycle at the G2/M phase, thereby accelerating pancreatitis-initiated PDAC. Carfilzomib is an innovative candidate drug that can inhibit pancreatitis-initiated PDAC through targeted inhibition of HTRA1.

Insufficient HtrA2 causes meiotic defects in aging germinal vesicle oocytes

BACKGROUND

High-temperature requirement protease A2 (HtrA2/Omi) is a mitochondrial chaperone that is highly conserved from bacteria to humans. It plays an important role in mitochondrial homeostasis and apoptosis. In this study, we investigated the role of HtrA2 in mouse oocyte maturation.

METHODS

The role of HtrA2 in mouse oocyte maturation was investigated by employing knockdown (KD) or overexpression (OE) of HtrA2 in young or old germinal vesicle (GV) oocytes. We employed immunoblotting, immunostaining, fluorescent intensity quantification to test the HtrA2 knockdown on the GV oocyte maturation progression, spindle assembly checkpoint, mitochondrial distribution, spindle organization, chromosome alignment, actin polymerization, DNA damage and chromosome numbers and acetylated tubulin levels.

RESULTS

We observed a significant reduction in HtrA2 protein levels in aging germinal vesicle (GV) oocytes. Young oocytes with low levels of HtrA2 due to siRNA knockdown were unable to complete meiosis and were partially blocked at metaphase I (MI). They also displayed significantly more BubR1 on kinetochores, indicating that the spindle assembly checkpoint was triggered at MI. Extrusion of the first polar body (Pb1) was significantly less frequent and oocytes with large polar bodies were observed when HtrA2 was depleted. In addition, HtrA2 knockdown induced meiotic spindle/chromosome disorganization, leading to aneuploidy at metaphase II (MII), possibly due to the elevated level of acetylated tubulin. Importantly, overexpression of HtrA2 partially rescued spindle/chromosome disorganization and reduced the rate of aneuploidy in aging GV oocytes.

CONCLUSIONS

Collectively, our data suggest that HtrA2 is a key regulator of oocyte maturation, and its deficiency with age appears to contribute to reproduction failure in females.

Differential molecular mechanistic behavior of HDACs in cancer progression

Genetic aberration including mutation in oncogenes and tumor suppressor genes transforms normal cells into tumor cells. Epigenetic modifications work concertedly with genetic factors in controlling cancer development. Histone acetyltransferases (HATs), histone deacetylases (HDACs), DNA methyltransferases (DNMTs) and chromatin structure modifier are prospective epigenetic regulators. Specifically, HDACs are histone modifiers regulating the expression of genes implicated in cell survival, growth, apoptosis, and metabolism. The majority of HDACs are highly upregulated in cancer, whereas some have a varied function and expression in cancer progression. Distinct HDACs have a positive and negative role in controlling cancer progression. HDACs are also significantly involved in tumor cells acquiring metastatic and angiogenic potential in order to withstand the anti-tumor microenvironment. HDACs' role in modulating metabolic genes has also been associated with tumor development and survival. This review highlights and discusses the molecular mechanisms of HDACs by which they regulate cell survival, apoptosis, metastasis, invasion, stemness potential, angiogenesis, and epithelial to mesenchymal transitions (EMT) in tumor cells. HDACs are the potential target for anti-cancer drug development and various inhibitors have been developed and FDA approved for a variety of cancers. The primary HDAC inhibitors with proven anti-cancer efficacy have also been highlighted in this review.

The multifaced role of HtrA1 in the development of joint and skeletal disorders

HtrA1 (High temperature requirement A1) family proteins include four members, widely conserved from prokaryotes to eukaryotes, named HtrA1, HtrA2, HtrA3 and HtrA4. HtrA1 is a serine protease involved in a variety of biological functions regulating many signaling pathways degrading specific components and playing key roles in many human diseases such as neurodegenerative disorders, pregnancy complications and cancer. Due to its role in the breakdown of many ExtraCellular Matrix (ECM) components of articular cartilage such as fibronectin, decorin and aggrecan, HtrA1 encouraged many researches on studying its role in several skeletal diseases (SDs). These studies were further inspired by the fact that HtrA1 is able to regulate the signaling of one of the most important cytokines involved in SDs, the TGFβ-1. This review aims to summarize the data currently available on the role of HtrA1 in skeletal diseases such as Osteoporosis, Rheumatoid Arthritis, Osteoarthritis and Intervertebral Disc Degeneration (IDD). The use of HtrA1 as a marker of frailty in geriatric medicine would represent a powerful tool for identifying older individuals at risk of developing skeletal disorders, evaluating an appropriate intervention to improve quality care in these people avoiding or improving age-related SDs in the elderly population.

Ongoing controversies and recent insights of the ARMS2-HTRA1 locus in age-related macular degeneration

Age-related macular degeneration (AMD) is the most common cause of central vision loss among elderly populations in industrialized countries. Genome-wide association studies have consistently associated two genomic loci with progression to late-stage AMD: the complement factor H (CFH) locus on chromosome 1q31 and the age-related maculopathy susceptibility 2-HtrA serine peptidase 1 (ARMS2-HTRA1) locus on chromosome 10q26. While the CFH risk variant has been shown to alter complement activity, the ARMS2-HTRA1 risk haplotype remains enigmatic due to high linkage disequilibrium and inconsistent functional findings spanning two genes that are plausibly causative for AMD risk. In this review, we detail the genetic and functional evidence used to support either ARMS2 or HTRA1 as the causal gene for AMD risk, emphasizing both the historical development and the current understanding of the ARMS2-HTRA1 locus in AMD pathogenesis. We conclude by summarizing the evidence in favor of HTRA1 and present our hypothesis whereby HTRA1-derived ECM fragments mediate AMD pathogenesis.

The interplay of oxidative stress and ARMS2-HTRA1 genetic risk in neovascular AMD

Age-related macular degeneration (AMD) is the leading cause of vision loss in adults over 60 years old globally. There are two forms of advanced AMD: “dry” and “wet”. Dry AMD is characterized by geographic atrophy of the retinal pigment epithelium and overlying photoreceptors in the macular region; whereas wet AMD is characterized by vascular penetrance from the choroid into the retina, known as choroidal neovascularization (CNV). Both phenotypes eventually lead to loss of central vision. The pathogenesis of AMD involves the interplay of genetic polymorphisms and environmental risk factors, many of which elevate retinal oxidative stress. Excess reactive oxygen species react with cellular macromolecules, forming oxidation-modified byproducts that elicit chronic inflammation and promote CNV. Additionally, genome-wide association studies have identified several genetic variants in the age-related maculopathy susceptibility 2/high-temperature requirement A serine peptidase 1 (ARMS2-HTRA1) locus associated with the progression of late-stage AMD, especially the wet subtype. In this review, we will focus on the interplay of oxidative stress and HTRA1 in drusen deposition, chronic inflammation, and chronic angiogenesis. We aim to present a multifactorial model of wet AMD progression, supporting HTRA1 as a novel therapeutic target upstream of vascular endothelial growth factor (VEGF), the conventional target in AMD therapeutics. By inhibiting HTRA1’s proteolytic activity, we can reduce pro-angiogenic signaling and prevent proteolytic breakdown of the blood-retina barrier. The anti-HTRA1 approach offers a promising alternative treatment option to wet AMD, complementary to anti-VEGF therapy.

Expression of HTRA Genes and Its Association with Microsatellite Instability and Survival of Patients with Colorectal Cancer

HtrA proteases regulate cellular homeostasis and cell death. Their dysfunctions have been correlated with oncogenesis and response to therapeutic treatment. We investigated the relation between HtrA1-3 expression and clinicopathological, and survival data, as well as the microsatellite status of tumors. Sixty-five colorectal cancer patients were included in the study. The expression of HTRA1-3 was estimated at the mRNA and protein levels by quantitative PCR and immunoblotting. Microsatellite status was determined by high-resolution-melting PCR. We found that the HTRA1 mRNA level was higher in colorectal cancer tissue as compared to the unchanged mucosa, specifically in primary lesions of metastasizing cancer. The levels of HtrA1 and HtrA2 proteins were reduced in tumor tissue when compared to unchanged mucosa, specifically in primary lesions of metastasizing disease. Moreover, a decrease in HTRA1 and HTRA2 transcripts' levels in cancers with a high level of microsatellite instability compared to microsatellite stable ones has been observed. A low level of HtrA1 or/and HtrA2 in cancer tissue correlated with poorer patient survival. The expression of HTRA1 and HTRA2 changes during colorectal carcinogenesis and microsatellite instability may be, at least partially, associated with these changes. The alterations in the HTRA1/2 genes' expression are connected with metastatic potential of colorectal cancer and may affect patient survival.

Effect of HtrA1 Polymorphism on Sensitivity to Chemotherapy in Patients with Colon Cancer

BACKGROUND This study was performed to estimate the genetic effects of HtrA1 polymorphisms rs1049331 and rs11200638 on treatment response in stage III colon cancer patients receiving 5-FU-based chemotherapy. MATERIAL AND METHODS A total of 105 stage III colon cancer patients who received postoperative 5-FU based adjuvant chemotherapy were included in our study. Chemotherapy was performed in 3 cycles for the patients. HtrA1 rs1049331 and rs11200638 polymorphisms were genotyped via polymerase chain reaction with sequencing method. The treatment response was estimated according to the RECIST guidelines. RESULTS The response rate of the eligible patients was 53.33%. For rs1049331, the presences of TT genotype and T allele indicted reduced chemotherapy sensitivity (adjusted TT: OR=1.736, 95%CI: 1.001-3.011, P=0.049; T: OR=1.801, 95%CI: 1.054-2.932, P=0.039). The rs11200638 polymorphism had no significant association with chemotherapy sensitivity in the study population (P>0.05 for all). CONCLUSIONS HtrA1 rs1049331 polymorphism, but not rs11200638 polymorphism, can influence individual sensitivity to 5-FU-based treatment in stage III colon cancer patients.

Transition of the abnormal Savda syndrome to the hepatic carcinoma shifted unfolded protein response to autophagy was partly reversed by Savda Munziq in a rat model

OBJECTIVES

In Uighur medicine, abnormal Savda Munziq (AMSq) is an adjuvant therapy for cancer patients with abnormal Savda syndrome (ASS) who exhibit the highest degree of pathogenicity and malignancy. The aim of the study was to understand the role(s) of AMSq in cancer patients with ASS.

METHODS

A total of 125 rats were divided into groups: control (NC) (n = 15), ASS (n = 25), ASS with hepatic carcinoma (ASSHC) (n = 25) as well as ASSHC treated with low dose (ASSHC-L, n = 20), medium dose (ASSHC-M, n = 20) and high dose (ASSHC-H, n = 20) AMSq. Changes in the unfolded protein response (UPR) and autophagy were analyzed by RT profiler PCR array kits, which covered 84 UPR and 84 autophagy related genes. Protein expression analyses of LC3B, ATG8, GRP78 and CHOP were carried out using western blotting.

RESULTS

CHOP and GRP78 expression was enhanced in ASS and ASSHC compared to NC rats and further increased AMSq dose-dependently, indicating an UPR triggering effect of AMSq. The ratios of ATG8/LCB3II-LCB3I protein were reduced in ASSHC rats, an effect which was partly reversed by AMSq. Compared to NC rats in the ASS group, 24 UPR genes were significantly upregulated and 3 downregulated, whereas only 5 autophagy genes were significantly upregulated and 5 downregulated. Compared to NC rats in the ASSHC group, 15 UPR genes were significantly upregulated and 10 downregulated, whereas 16 autophagy genes were significantly upregulated and 8 downregulated. The RT profiler data indicated a shift from UPR in the ASS to the autophagy response in ASSHC rats. ASMq effects on ASSHC rats comprised significant downregulation of 10 autophagy and 2 UPR genes.

CONCLUSION

The transformation into hepatic cancer cells included a shift from endoplasmic reticulum stress-related UPR to autophagy gene activation, an effect which could be partly reversed by ASMq.

HTRA1 promotes transdifferentiation of normal fibroblasts to cancer-associated fibroblasts through activation of the NF-κB/bFGF signaling pathway in gastric cancer

Cancer-associated fibroblasts comprise the major stromal cell populations in gastric cancer, which is a significant contributor to cancer-related death worldwide. As a member of the serine protease family, HTRA1 is reportedly involved in malignant transformation of various tumor types. In the present study, we observed that HTRA1 is positively correlated with α-SMA expression in gastric cancer tissues, which was also confirmed by correlation analysis and Gene Set Enrichment Analysis (GSEA) using the GEO database. Upregulation of HTRA1 in gastric cancer cell lines induces expression of α-SMA in normal fibroblasts. To explore how HTRA1 activates normal fibroblasts, an ELISA assay was performed. Secretion of bFGF/FGF2 from gastric cancer cells was significantly increased in response to HTRA1 overexpression. However, upreguation of α-SMA in normal fibroblasts induced by HTRA1 was restored by inhibiting the expression of bFGF. Furthermore, HTRA1 promotes bFGF/FGF2 expression through activation of NF-κB signaling in gastric cancer cells. Inhibition of the NF-κB signaling pathway partially restored baseline expression levels of α-SMA induced by HTRA1. In conclusion, HTRA1 promotes transdifferentiation of normal fibroblasts to cancer-associated fibroblasts by increasing bFGF/FGF2 expression, which is dependent upon activation of NF-κB signaling in gastric cancer.

Inactivation of the serine protease HTRA1 inhibits tumor growth by deregulating angiogenesis

The serine protease HTRA1 is involved in several vascular diseases and its expression is often deregulated in cancer. We aimed at identifying how HTRA1 in the vasculature affects tumor growth. Here we report that silencing of HTRA1 in cultured endothelial cells increased migration rate and tube formation, whereas forced HTRA1 expression impaired sprouting angiogenesis. Mechanistically, endothelial HTRA1 expression enhanced Delta/Notch signaling by reducing the amount of the weak Notch ligand JAG1. HTRA1 physically interacted with JAG1 and cleaved it within the intracellular domain, leading to protein degradation. Expression of a constitutive active Notch1 prevented the hypersprouting phenotype upon silencing of HTRA1. In HtrA1-deficient mice, endothelial Notch signaling was diminished and isolated endothelial cells had increased expression of VEGF receptor-2. Growth of syngeneic tumors was strongly impaired in HtrA1^-/- mice. The tumor vasculature was much denser in HtrA1^-/- mice and less covered with mural cells. This chaotic and immature vascular network was poorly functional as indicated by large hypoxic tumor areas and low tumor cell proliferation rates. In summary, inhibition of HTRA1 in the tumor stroma impaired tumor progression by deregulating angiogenesis.