Biomedical subjects

Laurent Brard

Publications and source records attributed to Laurent Brard.

7 recordsLinked to original sources

PubMed2006

Does the platinum-free interval predict the incidence or severity of hypersensitivity reactions to carboplatin? The experience from Women and Infants' Hospital.

OBJECTIVES: Carboplatin (C) is a standard treatment for gynecologic cancers, but its use in recurrence is associated with an increased risk of hypersensitivity reactions (HSR) in those previously treated with C. However, there is no way to predict those at risk for a C-HSR. We sought to evaluate whether the platinum-free interval (PFI) was predictive of incidence and severity of HSRs. METHODS: Patients treated with C between 1/99 and 12/2005 were identified through our chemotherapy database. Records were reviewed in those receiving multiple C regimens or with C HSR. Severity was defined as mild or severe based on symptoms. RESULTS: 126 patients were identified who had multiple C regimens. 63 (50%) experienced C HSRs of which 36 (29%) were severe. The incidence of C HSR was 25.8% for PFI < 12 months and 56.5% if > or = 12 months (p=0.0023). The incidence of a severe C HSR significantly increased with time as well: 6.5% PFI < 12 months, 23.9% PFI 12-24 months and 47% PFI > or = 24 months (p=0.0091). Of those receiving a 3rd regimen of C, 8/8 had a HSR and these were severe in seven (88%). Of note, 60 patients received > 8 (range 9-19) cycles with the first C regimen, and none of the patients reacted after cycle 8. CONCLUSIONS: A duration of greater than 12 months between C regimens is associated with an increased risk of both any--and severe--HSR. Our data also suggests that upfront treatment with C beyond eight cycles is not associated with an increased risk of HSR.

Adult↗

PubMed2006

Phenethyl isothiocyanate (PEITC) inhibits growth of ovarian cancer cells by inducing apoptosis: role of caspase and MAPK activation.

OBJECTIVE: Epithelial ovarian cancer has the highest mortality rate among gynecologic cancers. Chemotherapy is an essential component of its treatment. While isothiocyanates are known to possess chemopreventive effects against various cancers, yet little is known about their chemotherapeutic potential in ovarian cancer (OC). In the present study, we examined the antiproliferative and apoptotic effect of phenethyl isothiocyanate (PEITC), a naturally occurring isothiocyanate on OVCAR-3 cells. METHODS: Cytotoxic activity of PEITC on OVCAR-3 cells was determined using cell proliferation, apoptosis (DNA fragmentation and TUNEL assay) and caspase-activation studies. The role of PARP-1, Bax, and Bcl-2 in apoptosis was analyzed by Western blotting. Activation of JNK1/2, p38, Akt, ERK1/2, and c-Myc was examined by immunoblotting. Specific inhibitors of caspases, JNK1/2, p38, and MEK were used to corroborate these data. RESULTS: PEITC was cytotoxic to OVCAR-3 cells, and inhibited proliferation in a dose-dependent fashion (IC(50) = 23.2 microM). PEITC induced apoptosis by activating caspase-3 and -9, without capsase-8 activation. Anti-apoptotic Bcl-2 levels were suppressed while pro-apoptotic Bax levels were enhanced. PEITC suppressed activation of Akt, ERK1/2, and the expression of transcription factor c-Myc, while simultaneously activating pro-apoptotic p38 and JNK1/2. Specific inhibitors of caspase-3 and -9, JNK1/2, and p38 reversed the cytotoxic effect of PEITC. CONCLUSIONS: These findings demonstrate that PEITC exhibits cytotoxicity towards OVCAR-3 cells and induces apoptosis via caspase-9 and -3 pathways. PEITC inhibits Akt, ERK1/2 survival signaling, and c-Myc while simultaneously activating pro-apoptotic p38 and JNK1/2. Systematic preclinical and clinical trials with PEITC in ovarian cancer are indicated.

Apoptosis↗

PubMed2006

The effect of total parenteral nutrition on the survival of terminally ill ovarian cancer patients.

OBJECTIVES: Total parenteral nutrition (TPN) for terminal ovarian cancer patients remains controversial. In this study, we compared survival from time of terminal intestinal obstruction (TIO) diagnosis in patients who received TPN versus those who did not. METHODS: A historical cohort of 55 patients with stage IIIC/IV epithelial ovarian cancer hospitalized for TIO between 1994 and 2002 was studied. All patients were previously treated with paclitaxel/platinum following cytoreductive surgery. Exposure was administration of TPN after TIO. The primary outcome was survival from TIO diagnosis to death. Number of chemotherapy cycles completed after TIO diagnosis, major complications of TPN, and demographics were measured. Survival analysis was performed using Kaplan-Meier methods. RESULTS: The median survival from time of TIO diagnosis was 72 days (range 16-485) for patients receiving TPN and 41.0 days (range 4-133) for those not receiving TPN (P = 0.05), but no difference in survival was observed when adjusting for chemotherapy. Overall survival [median 23 (range 6-67) vs. 35 months (range 8-67), P = 0.03] was shorter for the TPN group. Demographic data were similar in both groups. Patients receiving TPN after obstruction were more likely to undergo concurrent chemotherapy (64 vs. 26%, P = 0.004). One major TPN-related complication was found. CONCLUSIONS: Ovarian cancer patients with TIO receiving TPN had a median survival benefit of 4 weeks. This benefit decreased when patients were treated with concurrent chemotherapy. Issues of cost, quality of life, and human values need to be investigated to assess the full impact of TPN in this patient population.

Cohort Studies↗

PubMed2006

Inhibition of angiogenesis by vitamin D-binding protein: characterization of anti-endothelial activity of DBP-maf.

Angiogenesis is a complex process involving coordinated steps of endothelial cell activation, proliferation, migration, tube formation and capillary sprouting with participation of intracellular signaling pathways. Regulation of angiogenesis carries tremendous potential for cancer therapy. Our earlier studies showed that vitamin D-binding protein-macrophage activating factor (DBP-maf) acts as a potent anti-angiogenic factor and inhibits tumor growth in vivo. The goal of this investigation was to understand the effect of DBP-maf on human endothelial cell (HEC) and the mechanism of angiogenesis inhibition. DBP-maf inhibited human endothelial cell (HEC) proliferation by inhibiting DNA synthesis (IC(50) = 7.8 +/- 0.15 microg/ml). DBP-maf significantly induced S- and G0/G1-phase arrest in HEC in 72 h. DBP-maf potently blocked VEGF-induced migration, tube-formation of HEC in a dose dependent manner. In addition, DBP-maf inhibited growth factor-induced microvessel sprouting in rat aortic ring assay. Moreover, DBP-maf inhibited VEGF signaling by decreasing VEGF-mediated phosphorylation of VEGFR-2 and ERK1/2, a downstream target of VEGF signaling cascade. However, Akt activation was not affected. These studies collectively demonstrate that DBP-maf inhibits angiogenesis by blocking critical steps such as HEC proliferation, migration, tube formation and microvessel sprouting. DBP-maf exerts its effect by inhibiting VEGR-2 and ERK1/2 signaling cascades. Understanding the cellular and molecular mechanisms of anti-endothelial activity of DBP-maf will allow us to develop it as an angiogenesis targeting novel drug for tumor therapy.

Cell Migration Inhibition↗

PubMed2006

Benzyl isothiocyanate (BITC) induces apoptosis in ovarian cancer cells in vitro.

Advanced ovarian cancer (OC) is not curable by surgery alone and chemotherapy is essential for its treatment. Isothiocyanates have been shown to inhibit carcinogen-induced tumorigenesis in animal models, yet no efforts have been made to determine their therapeutic potential in OC. In the present study, we investigated the mechanism of the anti-proliferative and apoptotic activity of benzyl isothiocyanate (BITC) in OC. BITC inhibited the proliferation of OC cells and induced apoptosis in OC cells. Apoptosis was induced by a strong activation of caspase-3 and -9, and cleavage of PARP-1. However, caspase-8 was not activated by BITC. Cytotoxic effects of BITC were reversed by the inhibition caspase-3 and -9 specific inhibitors. BITC showed a concentration dependent decrease in the levels of Bcl-2 with a concomitant increase in Bax levels. In addition, BITC activated proapoptotic signaling by phosphorylation JNK1/2 and p38 while simultaneously inhibiting survival signaling mediated by ERK1/2 and Akt phosphorylation in a dose-dependent manner. While JNK inhibitor SP600125 and p38 inhibitor SB203580, abolished the cytotoxic effect of BITC, MEK inhibitor, PD98059 and PI3 kinase inhibitor, LY294002 failed to show such reversal indicating a critical role played by JNK1/2 and p38 signaling in apoptosis induced by BITC. In summary, our studies demonstrate that BITC inhibits proliferation of OC cells and induces apoptosis via caspase-9 and -3 pathways. BITC inhibits ERK1/2 and Akt survival signaling while simultaneously activating pro-apoptotic p38 and JNK1/2. Therefore, BITC can be potentially developed as a therapeutic agent to treat OC.

Animals↗

PubMed2005

Inguinal sentinel node dissection versus standard inguinal node dissection in patients with vulvar cancer: A comparison of the size of metastasis detected in inguinal lymph nodes.

OBJECTIVE: The emergence of sentinel lymph node (SLN) technology has provided the ability for an in depth pathologic evaluation for the detection of metastasis to lymph nodes through the use of ultra-staging. The SLN has been shown to be predictive of the metastatic status of its nodal basin. More recently, SLN dissections have been employed in the evaluation of the inguinal lymphatic basins in patients with vulvar malignancies. We hypothesize that the average size of metastasis detected in non-palpable inguinal lymph nodes is smaller when detected through the use of SLN dissection and ultra-staging versus complete inguinal node dissection (CND). METHODS: This was an IRB approved retrospective study. The tumor registry database was searched to identify all patients diagnosed with a vulvar malignancy from 1990 to 2004. The records were reviewed to identify patients with inguinal lymph node metastasis. Only patients with non-palpable inguinal lymph nodes (metastasis 1 cm or less) were included in the analysis. All pathology slides were reviewed. The smallest metastatic foci of cells were measured from lymph nodes obtained through the traditional complete inguinal lymph node dissection (CND) and compared with the largest metastatic foci of cells detected in sentinel lymph node dissections. The mean size and standard deviation for each group was calculated and analyzed with a Mann-Whitney test. RESULTS: There were 336 inguinal node dissections performed in patients identified with a vulvar malignancy. SLN dissections were performed in 52 groins and CND in 284 groins. Fifty-eight patients were found to have metastatic disease to the inguinal lymph nodes. Thirty of these patients had no evidence of lymph node metastasis on clinical exam or at the time of their EUA. There were 7 groins with metastasis detected through an SLN and 23 groins through a CND. The mean size of the metastatic foci detected in the SLN group was 2.52 mm (SD 1.55) and in the CND group was 4.35 mm (SD 2.63). This was not statistically significant (P = 0.109). However, when comparing the detection of micrometastasis in each set, there was a significant difference (P = 0.02) in the detection of the size of metastasis detected with smaller cluster of cells detected in the SLN group. CONCLUSION: SLN dissection with ultra-staging allows for a more extensive pathologic examination of lymph nodes and may allow for the detection of smaller tumor foci than the traditional pathological examination of lymph nodes obtained from a CND. The clinical implication of the detection of these micrometastasis and smaller metastasis remains to be determined.

Aged↗

PubMed2005

Iron chelators deferoxamine and diethylenetriamine pentaacetic acid induce apoptosis in ovarian carcinoma.

OBJECTIVES: Ovarian cancer remains a leading cause of death in women and development of new therapies is essential. Deprivation of iron (Fe), an essential micro-nutrient, by chelation is known to inhibit proliferation of several human cancers but its potential in ovarian cancer treatment remains unknown. We have evaluated the anti-proliferative activities of iron chelators, deferoxamine (DFO), and diethylenetriamine pentaacetic acid (DTPA), in human and rat ovarian cancer cells. METHODS: The effect of DFO and DTPA on CaOV-3 (human) and NUTU-19 (rat) ovarian cancer cells was determined by cell proliferation and apoptosis assays (Hoechst staining, DNA fragmentation, and caspase activation), cell cycle analysis, and Fe supplementation studies. RESULTS: DFO and DTPA were cytotoxic to ovarian cancer cells in a dose- and time-dependent manner. DFO inhibited proliferation of NUTU-19 and CaOV-3 cells (IC(50) at 45 and 280 microM, respectively), while DTPA inhibited proliferation of only NUTU-19 cells (IC(50) at 50 microM), at 48 h. DNA synthesis was inhibited in CaOV-3 cells by DFO (>90% at 200 microM) and in NUTU-19 by both DFO and DTPA (>90% at 50 microM). Fe supplementation effectively reversed the cytotoxic effects of DFO and DTPA. Cell cycle analysis showed a G0/G1- and S-phase block with increased apoptosis. DNA fragmentation analysis confirmed apoptosis. Increase in caspase-3, -8, and -9 activities ( approximately 2.4-fold) was associated with apoptosis. CONCLUSIONS: Our studies show that Fe chelators suppress ovarian cancer growth by inhibiting proliferation and inducing apoptosis. Therefore, Fe chelators can be potentially developed as novel therapeutic agents to treat ovarian cancer.

Animals↗