The field of lipidomics has been significantly advanced by mass spectrometric analysis. The distinction and quantitation of the unsaturated lipid isomers, however, remain a long-standing challenge. In this study, we have developed an analytical tool for both identification and quantitation of lipid C=C location isomers from complex mixtures using online Paternò-Büchi reaction coupled with tandem mass spectrometry (MS/MS). The potential of this method has been demonstrated with an implementation into shotgun lipid analysis of animal tissues. Among 96 of the unsaturated fatty acids and glycerophospholipids identified from rat brain tissue, 50% of them were found as mixtures of C=C location isomers; for the first time, to our knowledge, the quantitative information of lipid C=C isomers from a broad range of classes was obtained. This method also enabled facile cross-tissue examinations, which revealed significant changes in C=C location isomer compositions of a series of fatty acids and glycerophospholipid (GP) species between the normal and cancerous tissues.Paternò-Büchi reaction | glycerophospholipids | photochemical reaction | lipid biomarkers | cancerous tissue analysis L ipids play a multitude of crucial roles in biological systems by serving as building blocks of cell membranes, sources for energy storage, and media for signal transduction (1-3). Unveiling the mechanisms and networks behind lipid homeostasis calls for sensitive, quantitative, and molecularly specific lipid analysis (4). The recent advancement in mass spectrometry (MS) for bioanalysis has enabled the field of lipidomics (5, 6) by allowing global identification and quantitation of lipid species at high speed (7-9) and providing information of lipid-lipid (10, 11) and lipidprotein interactions (12, 13) at systems level. These capabilities further expedite research on lipid biomarker discovery and metabolite flux analysis (14-16). Among many analytical figures of merit, high molecular specificity is a distinct feature of the MSbased approaches. Rich structural information of lipids in complex biological samples can now be routinely obtained, including the classes of the lipids, fatty acyl/alkyl composition, and even the sn positions of the fatty acyl/alkyl chains (17-19). The locations of the carbon-carbon double bonds (C=C) in the lipids, however, have rarely been identified using commercial MS systems and therefore have been either assumed or not reported in a large body of literatures for lipid study (20).The MS/MS methods, especially those involving low-energy collision-induced dissociation (CID), have not been effective in locating C=C bond locations, which is due to the high bond dissociation energies associated with cleaving a C=C bond. Without characteristic fragment ions produced, the C=C locations cannot be determined using MS/MS. To tackle this problem, two MS approaches have been explored, each with successes achieved but also with limitations observed. The first one employs C=C specific chemical derivatizations before MS analysis. T...

Orthotopic liver transplantation (OLT) is the only curative therapy of HCC with underlying cirrhosis, but due to HCC metastasis and recurrence, its benefit is limited to a small population who meet the strict selection criteria. We previously reported that Licartin ([ 131 I]mAb HAb18G/CD147) was safe and effective in treating HCC patients, and its antigen, HAb18G/ CD147, was closely related to HCC invasion and metastasis. Here, we reported a randomized controlled trial to assess the post-OLT antirecurrence efficacy of Licartin in advanced HCC patients. We randomized 60 post-OLT patients with HCC, who were at tumor stage 3/4 and outside the Milan criteria before OLT, into 2 groups. Three weeks after OLT, the treatment group received 15.4 MBq/kg of Licartin, while the control group received placebo intravenously for 3 times with an interval of 28 days. At 1-year follow-up, the recurrence rate significantly decreased by 30.4% (P ‫؍‬ 0.0174) and the survival rate increased by 20.6% (P ‫؍‬ 0.0289) in the treatment group, compared with those in the control group. For the control group versus the treatment group, the hazard ratio for recurrence H epatocellular carcinoma is the most common type of primary liver cancer and ranks sixth among cancers as a cause of death worldwide. 1 It is a highly malignant tumor characterized by rapid progression, poor prognosis, and frequent tumor recurrence. It has an annual incidence rate of 564,000 cases, and 55% of those are in China. 2 The mean natural survival time was reported to be only 3-6 months due to the rapid progression of tumor, especially the spread and metastasis. 3,4 Surgery is the preferred treatment, but less than 20% of patients have the chance to be treated surgically Abbreviations: AFP, alpha fetoprotein; CI, confidence interval; DBIL, direct bilirubin; mAb, monoclonal antibody; OLT, orthotopic liver transplantation; TNM, tumor-nodes-metastasis. From the

CD147 molecule is reported to be correlated with the malignancy of some cancers; however, it remains unclear whether it is involved in the progression of hepatocellular carcinoma (HCC). Here, we investigated the function of HAb18G/CD147, a member of CD147 family, and its antibodies, HAb18 and LICARTIN, in HCC invasion and metastasis. We observed that HAb18G/CD147 gene silence in HCC cells significantly decreased the secretion of matrix metalloproteinase (MMP) and the invasive potential of HCC cells (P < 0.001). MMP silence in HCC cells also significantly suppressed the invasion of the cells when cocultured with fibroblasts; however, its inhibitory effect was significantly weaker than that of both HAb18G/CD147 silence in HCC cells and that of MMP silence in fibroblasts (P < 0.001). Blocking the HAb18G/CD147 molecule on HCC cells with HAb18 monoclonal antibody resulted in a similar suppressive effect on MMP secretion and cell invasion, but with no significant effects on the cell growth. 131 I-labeled HAb18 F(ab ¶) 2 (LICARTIN), however, significantly inhibited the in vitro growth of HCC cells (P < 0.001). In an orthotopic model of HCC in nude mice, HAb18 and LICARTIN treatment effectively reduced the tumor growth and metastasis as well as the expression of three major factors in the HCC microenviroment (MMPs, vascular endothelial growth factor, and fibroblast surface protein) in the paracancer tissues. Overall, these results suggest that HAb18G/CD147 plays an important role in HCC invasion and metastasis mainly via modulating fibroblasts, as well as HCC cells themselves to disrupt the HCC microenviroment. LICARTIN can be used as a drug targeting to HAb18G/ CD147 in antimetastasis and recurrence therapy of HCC.

Abstract-Recent studies have indicated that angiotensin II (Ang II) can stimulate oxidative stress. The present study was conducted to assess the contribution of oxygen radicals to hypertension and regional circulation during Ang II-induced hypertension. With radioactive microspheres, the responses of systemic and regional hemodynamics to the membranepermeable, metal-independent superoxide dismutase mimetic 4-hydroxy-2,2,6,6-tetramethyl piperidinoxyl (tempol) were assessed in conscious Ang II-infused hypertensive rats. Ang II-infused rats (80 ng/min SC for 12 days: nϭ25) showed higher mean arterial pressure (MAP: 161Ϯ4 mm Hg) and total peripheral resistance (TPR: 1.59Ϯ0.08 mm Hg ⅐ min Ϫ1 ⅐ mL Ϫ1 ) than vehicle-infused normotensive rats (116Ϯ3 mm Hg and 0.95Ϯ0.04 mm Hg ⅐ min Ϫ1 ⅐ mL Ϫ1 , respectively; nϭ23). The blood flow rates in the brain, spleen, large intestine, and skin were significantly reduced in Ang II-infused rats compared with vehicle-infused rats, whereas rates in the lung, heart, liver, kidney, stomach, small intestine, mesenterium, skeletal muscle, and testis were similar. Vascular resistance was significantly increased in every organ studied except the lung, in which the resistance was similar. Tempol (216 mol/kg IV) significantly reduced MAP by 30Ϯ4% from 158Ϯ7 to 114Ϯ5 mm Hg and TPR by 35Ϯ6% from 1.57Ϯ0.17 to 0.95Ϯ0.04 mm Hg ⅐ min Ϫ1 ⅐ g Ϫ1 in Ang II-infused rats (nϭ9) but had no effect on these parameters in vehicle-infused rats (nϭ8). In Ang II-infused rats, tempol did not affect regional blood flow but significantly decreased vascular resistance in the brain (29Ϯ6%), heart (31Ϯ6%), liver (37Ϯ7%), kidney (30Ϯ7%), small intestine (38Ϯ6%), and large intestine (47Ϯ7%). Ang II-infused hypertensive rats showed doubled vascular superoxide production (assessed with lucigenin chemiluminescence), which was normalized by treatment with tempol (3 mmol/L, nϭ7). Further studies showed that the NO synthase inhibitor, N -nitro-L-arginine methyl ester (11 mol ⅐ kg Ϫ1 ⅐ min Ϫ1 IV, nϭ11) markedly attenuated the systemic and regional hemodynamic responses of tempol in Ang II-infused rats. These results suggest that in this model of hypertension, oxidative stress may have contributed to the alterations in systemic blood pressure and regional vascular resistance through inactivation of NO. (Hypertension. 2001;37:77-83.)

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