Hippocampal Expression of Cytochrome P450 1B1 in Penetrating Traumatic Brain Injury

Hippocampal dysfunction contributes to multiple traumatic brain injury sequala. Female rodents’ outcome is superior to male which has been ascribed the neuroprotective sex hormones 17β-estradiol and progesterone. Cytochrome P450 1B1 (CYP1B1) is an oxidative enzyme influencing the neuroinflammatory response by creating inflammatory mediators and metabolizing neuroprotective 17β-estradiol and progesterone. In this study, we aimed to describe hippocampal CYP1B1 mRNA expression, protein presence of CYP1B1 and its key redox partner Cytochrome P450 reductase (CPR) in both sexes, as well as the effect of penetrating traumatic brain injury (pTBI). A total 64 adult Sprague Dawley rats divided by sex received pTBI or sham-surgery and were assigned survival times of 1-, 3-, 5- or 7 days. CYP1B1 mRNA was quantified using in-situ hybridization and immunohistochemistry performed to verify protein colocalization. CYP1B1 mRNA expression was present in all subregions but greatest in CA2 irrespective of sex, survival time or intervention. At 3-, 5- and 7 days post-injury, expression in CA2 was reduced in male rats subjected to pTBI compared to sham-surgery. Females subjected to pTBI instead exhibited increased expression in all CA subregions 3 days post-injury, the only time point expression in CA2 was greater in females than in males. Immunohistochemical analysis confirmed neuronal CYP1B1 protein in all hippocampal subregions, while CPR was limited to CA1 and CA2. CYP1B1 mRNA is constitutively expressed in both sexes. In response to pTBI, females displayed a more urgent but brief regulatory response than males. This indicates there may be sex-dependent differences in CYP1B1 activity, possibly influencing inflammation and neuroprotection in pTBI.

DDRE-39. REPURPOSING CHEMOTHERAPIES AGAINST HIGH-RISK MENINGIOMAS WITH GUIDANCE BY METHYLATION PROFILES

Meningioma is the most common primary brain tumor with nearly thirty thousand new cases in the US every year. While most meningiomas are categorized as benign, they can still impact brain structures and result in disability or lethality. Currently, there is no widely accepted chemotherapy, and our understanding of the disease’s molecular characteristics is very limited. In this study, we aimed to identify druggable molecular targets for repurposing of chemotherapies against meningiomas. We analyzed previously published dataset of 493 meningioma patients by Felix Sahm et al (Lancet Oncology, 2017) for association with progression-free survival (PFS) and searched for candidate drugs targeting the pathways linked to poor patient prognosis. Our analyses indicated 981 genes for which methylation of mapped CpG sites was found to be consistently associated with shorter or longer PFS at FDR-adjusted p < 0.05. Using Cytoscape/Reactome FI software, we cross-referenced current cancer drugs that target these and identified docetaxel and raloxifene hydrochloride as potential candidates. In our vitro study, docetaxel caused apoptotic cell death in established and primary patient meningioma lines of various grades. IC50s of docetaxel in the seventeen meningioma cell lines tested ranged from 0.8nM to 4.4mM, which partially corresponded to the growth rates of these cells. As monotherapy, the effects of docetaxel on meningioma were attenuated by multidrug resistance protein 1 (ABCB1) and Cytochrome P450 1B1 (CYP1B1). Docetaxel at 2µM augment double-stranded DNA damage caused by irradiation in vitro, leading to increased cell death. In animal model, low doses of docetaxel and radiation therapy had synergistic effects, increasing survival of mice intracranially implanted with human meningioma cells. Our study will advance our understanding of molecular pathways driving meningioma and identify potential targeted therapies to bridge the current gap in treatment of the disease.

Incorporation of potent and selective cytochrome P450 1B1 inhibitors into Ru(II) scaffolds provides unprecedented control over enzyme activity with light

The cytochrome P450 family of enzymes (CYPs) are important targets for medicinal chemistry. Recently, CYP1B1 has emerged as a key player in chemotherapy resistance in the treatment of cancer. This enzyme is overexpressed in a variety of tumors, and is correlated with poor treatment outcomes; thus, it is desirable to develop CYP1B1 inhibitors to restore chemotherapy efficacy. However, possible off-target effects, such as inhibition of liver CYPs responsible for first pass metabolism, make selective inhibition a high priority to avoid possible drug-drug interactions and toxicity. Here we describe the creation of light-triggered CYP1B1 inhibitors as “prodrugs”, and achieve >6,000-fold improvement in potency upon activation with low energy (660 nm) light. The novel systems provide a selectivity index of 4,000–100,000 over other off-target CYPs. One key to the design was the development of novel, coordinating CYP1B1 inhibitors which suppress enzyme activity at pM concentrations in live cells. The coordinating group enforces inhibitor orientation in the active site by anchoring to the iron. The second essential component was the biologically compatible Ru(II) scaffold that cages the inhibitors before photochemical release. These Ru(II) photocages are anticipated to provide similar selectivity and control for any coordinating CYP inhibitors.

Cytochrome P450 1B1 Overexpression in Cervical Cancers: Cross-sectional Study

Background Current standard treatments for patients with recurrent cervical cancer are not very effective and are associated with severe toxicity. Recently, the rational approach for the discovery of new therapies for cervical cancer is based on the alterations in the molecular biology of cancer cells. One of the emerging molecular changes in cancer cells is the aberrant expression of cytochrome P450 1B1 (CYP1B1). This unique enzyme has been reported to be selectively overexpressed in several cancers. Objective The aim of this study was to examine CYP1B1 expression in cervical cancers and to assess the enzyme’s relationship with several clinicopathological features. Methods Immunohistochemistry was performed to examine CYP1B1 expression in 100 patient samples with cervical cancer and 10 patient samples with normal healthy cervical tissues. Results CYP1B1 was expressed in the majority of the cervical cancer samples (91/100, 91.0%) but not in normal healthy cervical samples. The difference in the expression of CYP1B1 between healthy and tumorous cervical tissues was significant (P=.01). Moreover, the frequency of CYP1B1 expression was found to be significantly higher in patients with advanced grades of the disease (P=.03) and in patients having metastasis to the lymph nodes (P=.01). Surprisingly, there was a significantly higher expression of CYP1B1 in patients with a high prevalence of human papilloma virus 16/18 (P=.04). Conclusions The differential profile of CYP1B1 expression between cervical cancer tissues and normal cervical tissues suggests that CYP1B1 may be used as a target for future therapeutic exploitations.

Possible Role of Cytochrome P450 1B1 in the Mechanism of Gemcitabine Resistance in Pancreatic Cancer

Patient-derived xenograft models reportedly represent original tumor morphology and gene mutation profiles. In addition, patient-derived xenografts are expected to recapitulate the parental tumor drug responses. In this study, we analyzed the pathways involved in gemcitabine resistance using patient-derived xenograft models of pancreatic cancer. The patient-derived xenograft models were established using samples from patients with pancreatic cancer. The models were treated with gemcitabine to better understand the mechanism of resistance to this anti-cancer drug. We performed comparative gene analysis through the next-generation sequencing of tumor tissues from gemcitabine-treated or non-treated patient-derived xenograft mice and gene set enrichment analysis to analyze mRNA profiling data. Pathway analysis of gemcitabine-treated patient-derived xenografts disclosed the upregulation of multiple gene sets and identified several specific gene pathways that could potentially be related to gemcitabine resistance in pancreatic cancer. Further, we conducted an in vitro analysis to validate these results. The mRNA expression of cytochrome P450 1B1 and cytochrome P450 2A6 was upregulated in a concentration-dependent manner following gemcitabine treatment. Moreover, the sensitivity to gemcitabine increased, and viable cells were decreased by the cytochrome P450 1B1 inhibitor, indicating that the cytochrome P450 1B1 pathway may be related to gemcitabine resistance in pancreatic cancer.

Abstract MP63: Cytochrome P450 1B1 Mediated Inhibition Of Group IV Cytosolic Phospholipase A 2 α In Paraventricular Nucleus Protects Female Mice From Angiotensin II-Induced Hypertension, Increased Renal Sympathetic Activity And Proteinuria

Recently we showed that 2-methoxyestradiol (2-ME), an estrogen (E2) metabolite generated by CYP1B1 (cytochrome P450 1B1) in the paraventricular nucleus (PVN), protects female mice from Ang (angiotensin) II-induced hypertension and increased renal sympathetic activity. We also demonstrated that group IV cPLA 2 α (cytosolic phospholipase A 2 α) in the brain contributes to Ang II-induced hypertension in male mice. This study was conducted to determine the contribution of central cPLA 2 α and its relationship to CYP1B1 in Ang II-induced hypertension in female mice. cPLA 2 α knockdown in the PVN by transduction with adenovirus (Ad)-cPLA 2 α-short hairpin (sh)RNA (200 nL, bilaterally, 1.0х10 12 pfu/mL) but not its control Ad-scrambled (Scr)-shRNA (2.5х10 11 pfu/mL) in ovariectomized (OVX) wild-type ( cPLA 2 α +/+ / Cyp1b1 +/+ , n=8/group) and intact cPLA 2 α +/+ / Cyp1b1 -/- (n=12/group) female mice attenuated the effect of Ang II (700 ng/kg/min, subcutaneous, osmotic pump, 2 weeks) to increase the systolic blood pressure (SBP, mmHg) as measured by tail-cuff (Day 12: 129±3 vs 168±7 and 119±3 vs 172±5, respectively, P<0.05). Moreover, reconstitution of cPLA 2 α in the PVN by transduction with Ad-cPLA 2 α-DNA (1.1х10 12 pfu/mL) but not its control Ad-GFP-DNA (1.0х10 11 pfu/mL) in OVX- cPLA 2 α -/- / Cyp1b1 +/+ mice (n=4/group) restored the effect of Ang II to increase SBP (Day 12: 163±7 vs 124±4, P<0.05). Furthermore, Ad-cPLA 2 α-shRNA but not Ad-Scr-shRNA transduction in the PVN in OVX- cPLA 2 α +/+ / Cyp1b1 +/+ and intact cPLA 2 α +/+ / Cyp1b1 -/- mice reduced and Ad-cPLA 2 α-DNA but not Ad-GFP-DNA transduction in the PVN in OVX- cPLA 2 α -/- / Cyp1b1 +/+ mice restored the effect of Ang II to increase the renal sympathetic activity as indicated by urinary norepinephrine level (ng/mL, 324±36 vs 707±94, 359±49 vs 979±70, 690±44 vs 421±43, respectively, n=4/group, P<0.05) and proteinuria (mg/24 hour, 4±1 vs 10±0.4, 3±0.4 vs 7±1, 9±0.8 vs 3±0.7, respectively, n=4/group, P<0.05). These data suggest that E2-CYP1B1 derived metabolite 2-ME protects against Ang II-induced hypertension, renal sympathetic activity, and proteinuria by inhibiting cPLA 2 α activity in the PVN. Thus, 2-ME and/or agents inhibiting cPLA 2 α activity could be useful for treating hypertension and its pathogenesis in females.

The Enhanced Immune Protection in Small Abalone Haliotis diversicolor Against a Secondary Infection With Vibrio harveyi

In recent years, more and more studies have shown that early pathogenic bacterial infection in invertebrates can enhance immunity and significantly reduce mortality when reinfected with the same pathogen. There are mechanisms to explain this phenomenon, but they are relatively few. In addition, dose-dependent primary infection is also associated with increased immunity. In the present study, the initial infection dose and mortality of abalone Haliotis diversicolor after reinfection with Vibrio harveyi were recorded, and the mechanism of immune enhancement was investigated by the transcriptomic response of abalone after two successive stimuli with V. harveyi. Priming with different concentrations of pathogen can enhance immunity; however, higher concentration is not always better. Compared with the first exposure, more genes were up-regulated after the second exposure. Among the commonly expressed genes, the immune related genes were significantly or persistently highly expressed after two infections and included pattern recognition receptors as well as immune effectors, such as toll-like receptors, perlucin 4, scavenger receptor class B-like protein, cytochrome P450 1B1-like, glutathione S-transferase 6, lysozyme and so on; in addition, these immune-related genes were mainly distributed in the pathways related to phagocytosis and calcium signaling. Among the specifically expressed genes, compared with the first infection, more genes were involved in the immune, metabolic and digestive pathways after the second infection, which would be more conducive to preventing the invasion of pathogens. This study outlined the mechanism of immune enhancement in abalone after secondary infection at the global molecular level, which is helpful for a comprehensive understanding of the mechanism of immune priming in invertebrates.

Cytochrome P450 1B1 Overexpression in Cervical Cancers: Cross-sectional Study (Preprint)

BACKGROUND Current standard treatments for patients with recurrent cervical cancer are not very effective and are associated with severe toxicity. Recently, the rational approach for the discovery of new therapies for cervical cancer is based on the alterations in the molecular biology of cancer cells. One of the emerging molecular changes in cancer cells is the aberrant expression of cytochrome P450 1B1 (CYP1B1). This unique enzyme has been reported to be selectively overexpressed in several cancers. OBJECTIVE The aim of this study was to examine CYP1B1 expression in cervical cancers and to assess the enzyme’s relationship with several clinicopathological features. METHODS Immunohistochemistry was performed to examine CYP1B1 expression in 100 patient samples with cervical cancer and 10 patient samples with normal healthy cervical tissues. RESULTS CYP1B1 was expressed in the majority of the cervical cancer samples (91/100, 91.0%) but not in normal healthy cervical samples. The difference in the expression of CYP1B1 between healthy and tumorous cervical tissues was significant (<i>P</i>=.01). Moreover, the frequency of CYP1B1 expression was found to be significantly higher in patients with advanced grades of the disease (<i>P</i>=.03) and in patients having metastasis to the lymph nodes (<i>P</i>=.01). Surprisingly, there was a significantly higher expression of CYP1B1 in patients with a high prevalence of human papilloma virus 16/18 (<i>P</i>=.04). CONCLUSIONS The differential profile of CYP1B1 expression between cervical cancer tissues and normal cervical tissues suggests that CYP1B1 may be used as a target for future therapeutic exploitations.

Meta-analysis of CYP1B1 gene mutations in primary congenital glaucoma patients

Primary congenital glaucoma (PCG) is a rare and severe form of glaucoma and is usually transmitted as an autosomal-recessive disease. However, PCG is more common in certain ethnic and geographic groups where consanguineous relationships are common. The importance of this review is to inspect the mutations in the cytochrome P450 1B1 gene (CYP1B1) and to highlight the interest of the genetic study of CYP1B1 mutations. An in-depth study was carried out by the following search engines: PubMed, Scopus, clinic key and direct science for articles that have been published from 2011 until 2020. One hundred and sixty-one mutations were found in 1641 tested patients and three families, including 78 novel mutations. We identified a no significant difference in the sex ratio and the bilaterality was reported in the majority of patients. We have shown through this study that inbreeding plays an important role in the pathogenesis of PCG transmission compared to the sporadic mutations that have been found in some cases. The majority of the included studies were from ASIA (64.3%), followed by Europe (17.85%), America (10.71%) and Africa (7.14%). The first and most common mutation in our study is 182 G>A (p.Gly61Glu). It was identified in Iran, Portugal and Saudi Arabia and for the first time in Brazil and Vietnam. The greatest number of mutations in common is p.Gly61Glu. Mainly within five countries: Iran, Portugal, Saudi Arabia, Brazil and Vietnam. The first step in PCG screening should be a genetic test looking for founder and common mutation coupled with a clinical examination.

New Perspectives of CYP1B1 Inhibitors in the Light of Molecular Studies

Human cytochrome P450 1B1 (CYP1B1) is an extrahepatic heme-containing monooxygenase. CYP1B1 contributes to the oxidative metabolism of xenobiotics, drugs, and endogenous substrates like melatonin, fatty acids, steroid hormones, and retinoids, which are involved in diverse critical cellular functions. CYP1B1 plays an important role in the pathogenesis of cardiovascular diseases, hormone-related cancers and is responsible for anti-cancer drug resistance. Inhibition of CYP1B1 activity is considered as an approach in cancer chemoprevention and cancer chemotherapy. CYP1B1 can activate anti-cancer prodrugs in tumor cells which display overexpression of CYP1B1 in comparison to normal cells. CYP1B1 involvement in carcinogenesis and cancer progression encourages investigation of CYP1B1 interactions with its ligands: substrates and inhibitors. Computational methods, with a simulation of molecular dynamics (MD), allow the observation of molecular interactions at the binding site of CYP1B1, which are essential in relation to the enzyme’s functions.