Arginase is upregulated in healthy women infected by oncogenic HPV types.

INTRODUCTION: The implication of arginase enzyme in Human Papillomavirus (HPV) infections has not been clearly elucidated. The present study investigates whether HPV infection is correlated with changes in plasmatic arginase activity and cervical ARG1 and ARG2 mRNA expression among infected women negative for intraepithelial lesions (NIL). MATERIEL AND METHODS: The present study included 300 women. The plasmatic arginase activity was evaluated by a colorimetric assay. Cervical HPV was detected by real-time PCR. The circulating viral load and ARG1 and ARG2 mRNA expression quantification were performed by quantitative real-time PCR. RESULTS: A significant increase in plasma arginase activity and ARG1 and ARG2 mRNA expression levels in cervical cells was observed among HPV-positive women compared to the HPV-negative group. The highest levels were significantly associated with oncogenic HPV, and increased arginase activity was associated with a high HPV circulating viral load. Moreover, the highest levels of arginase activity were observed in oncogenic HPV-positive inflammatory smears. DISCUSSION: These data suggest that HPV could modulate arginase activity and expression, which may restrict arginine bioavailability and inhibit this amino acid's antiviral properties. CONCLUSION: Our findings revealed that arginase activity and isoform gene expression were upregulated in women with HPV infection, particularly the oncogenic HPV types.

Indoleamine 2,3-dioxygenase gene expression and kynurenine to tryptophan ratio correlation with nasopharyngeal carcinoma progression and survival.

INTRODUCTION: Indoleamine 2,3-dioxygenase (IDO) is an immunosuppressive tryptophan-depleting enzyme expressed in nasopharyngeal carcinoma (NPC) tissue. However, IDO has not been reported in the peripheral blood of NPC patients. The aim of this study was to analyze, IDO1 and IDO2 messenger RNA (mRNA) expression, the kynurenine (Kyn) and tryptophan (Trp) plasma levels, their clinical values and their relationship with cytokine levels in NPC. METHODS: We evaluated IDO1 and IDO2 mRNA expression in peripheral blood mononuclear cells (PBMC) by quantitative real-time PCR, plasma Trp and Kyn levels by HPLC, and cytokine levels by ELISA in 75 NPC patients and 51 healthy controls. RESULTS: Compared to controls, IDO1 mRNA expression was significantly upregulated and IDO2 mRNA expression was significantly downregulated in PBMC of patients. Also compared to controls, plasma Kyn levels and Kyn/Trp ratio were significantly higher in patients. At the time of diagnosis, the plasma Kyn/Trp ratio was associated with advanced cancer status and was an independent prognostic factor for worse disease-specific survival. According to cancer stages, IDO1 mRNA expression was positively correlated with plasma Kyn/Trp ratio in patients with earlier stages (I-II-III) but negatively correlated in patients with the late-stage cancer (IV). Tumor necrosis factor-α, interleukin (IL)-6 and IL-10 levels were significantly higher in patients compared to controls. Moreover, and despite treatment, patients simultaneously carrying high plasma Kyn/Trp ratio and high plasma IL-6 and IL-10 levels at diagnosis died approximately 1 year after first diagnosis. CONCLUSION: Measuring blood IDO mRNA expression and Kyn/Trp ratio at diagnosis could be a potential marker to evaluate NPC progression and predict survival outcome.

Arginase is involved in cervical lesions progression and severity.

BACKGROUND: Little is known about the relationship between arginase, an immunosuppressive enzyme, and cervical lesions. The present study is aimed at evaluating arginase activity in plasma and mRNA arginase isoforms expression in cervical cells of patients with abnormal cytology and identifying their relationship with Human papillomavirus (HPV) related parameters such as: HPV type, HPV circulating viral load and anti-HPV16 IgG. METHODS: This study included 77 women with cervical lesions and 95 matched controls. Arginase activity was detected by colorimetric assay. Arginase mRNA expression and HPV viral load were evaluated by quantitative real time PCR and anti-HPV16 antibodies were assessed by ELISA. RESULTS: Compared to controls, the arginase activity was higher among women with cervicitis / low grade squamous intraepithelial lesions (LSIL) (OR: 1.872, 95% CI: 0.833-4.210), and also among women with high-grade squamous intraepithelial lesions (HSIL) / squamous cell carcinoma (SCC) (OR: 3.358, 95% CI: 1.670-8.910). Compared to controls, mRNA expression was significantly upregulated in women with cervical cervicitis and SIL for ARG1, and in women with cancer lesions for ARG2. Arginase activity was positively correlated to ARG2 mRNA expression but not to ARG1. High arginase activity was associated with HPV16, high levels of HPV viral load, and low levels of anti-HPV16 antibodies. CONCLUSIONS: Our findings demonstrated that arginase activity and isoforms expression were enhanced in women with HPV-related precancerous lesions and cervical cancer. Further studies are needed to identify how arginase enzyme induces disease progression and severity.