Pomolic acid exhibits anticancer potential against a docetaxel­resistant PC3 prostate cell line.

Prostate cancer (PC) is one of the leading causes of cancer­related death in the male population worldwide. Mortality of PC is dependent on tumor recurrence and its progression to metastatic disease. We examined the effects of pentacyclic triterpene pomolic acid (PA) on docetaxel­resistant PC3 cells. Cell viability was evaluated using the MTT assay. Apoptosis was evaluated by cell cycle analysis using flow cytometry. The activity of multiple drug resistance (MDR) proteins was determined by the accumulation of specific substrates [mitoxantrone, rhodamine 123 and 5­carboxyfluorescein diacetate (CFDA)]. The evaluation of epithelial to mesenchymal transition (EMT) proteins was conducted by immunocytochemical assays. It was demonstrated that PC3R cells presents multidrug resistance and EMT phenotype and express active P­gp/ABCB1 and MRP1/ABCC1. It was shown that PA strongly reduced the viability and induced apoptosis of both PC3 and PC3R cell lines. Moreover, PA bypassed P­gp/ABCB1, downmodulated MRP1/ABCC1 activities, and partially reverted EMT induced by DTX. Our goal was to evaluate the potential of PA for the development of novel strategies to treat castration­resistant PC.

Pomolic acid induces apoptosis and inhibits multidrug resistance protein MRP1 and migration in glioblastoma cells.

Glioblastoma (GBM), the most aggressive of primary brain tumors, determine short survival and poor quality of life. Therapies used for its treatment are not effective and chemotherapy failure is partially due to multidrug resistance (MDR) mechanisms present in the tumor cells. New therapeutic strategies are needed in order to improve survival in GBM. The present study investigated the activity of the pentacyclic triterpene pomolic acid (PA) in GBM. Pomolic acid decreased the viability and induced apoptosis of GBM cells as demonstrated by DNA fragmentation. It also induced uncoupling of mitochondria membrane potential and activation of caspase-3 and -9. Pomolic acid-induced apoptosis is dependent on reactive oxygen species (ROS) production as it is inhibited by anti-oxidant treatment. Pomolic acid also down-modulated the activity of the multidrug resistance associated protein 1 (MRP1) and inhibited migration of GBM cells. These results show that PA acts on several pathways of GBM drug resistance and therefore may be of potential interest for the treatment of this tumor.

Ultrasound-assisted Extraction of Ursolic Acid from the Flowers of Ixora coccinia Linn (Rubiaceae) and Antiproliferative Activity of Ursolic Acid and Synthesized Derivatives.

BACKGROUND: Ixora coccinea Linn (Rubiaceae) is an evergreen shrub with bright scarlet colored flowers found in several tropical and subtropical countries. It is used as an ornamental and medicinal plant. Phytochemical studies revealed that its major special metabolites are triterpene acids, such as ursolic and oleanolic acid. OBJECTIVE: To evaluate the isolation of ursolic acid (UA) (1) from methanol extracts of I. coccinea flowers through two methodologies, to prepare four derivatives, and to evaluate the cytotoxic effect against six cancer cell lines. MATERIALS AND METHODS: The UA was isolated from vegetal material by percolation at room temperature and by ultrasound-assisted extraction. The preparation of derivatives was performed according to literature methods, and the cytotoxic effects were evaluated using the MTT (3,4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide) assay. RESULTS: The most efficient extraction was achieved through ultrasound irradiation with a yield of 35% after KOH-impregnated silica in chromatography column. Furthermore, four derivatives (3, 5, 6, 7) of UA were prepared and evaluated, including 1, against two lung cancer (A549 and H460) and four leukemia (K562, Lucena, HL60, and Jurkat) cell lines. Generally, results showed that 1 and 7 were the most active compounds against the assayed cell lines. Also, the cytotoxic effects observed on terpenes 1 and 7 were higher when compared with cisplatin, used as positive control, with the exception of Jurkat cell line. CONCLUSION: The efficiency of such an alternative extraction method led to the principal and abundant active component, 1, of I. coccinea, thus representing a considerable contribution for promising triterpenoid in cancer chemotherapy. SUMMARY: The ultrasound-assisted extraction of Ixora coccinea flowers improved of the ursolic acid isolationMethanolic extract from flowers of I. coccinea provided, by ultrasound irradiation, after KOH-impregnated silica in chromatography column, the ursolic acid in 35% yieldThe ursolic acid and four derivatives were prepared and assayed against two lung cancer and four leukaemia cell linesThe ursolic acid and their 3-oxo-derivative, in general, were more cytotoxic when compared to cisplatin, used as positive control Abbreviations used: MTT: 3,4,5-dimethylthiazol-2-yl-2,5-diphenyltetrazolium bromide, RP: reverse phase, TLC: thin layer chromatography, KOH: potassium hydroxide, IR: infrared, DMF: dimethylformamide, DMSO: dimethyl sulfoxide, TEA: triethylamine, RT: room temperature, EtOAc: ethyl acetate, MeOH: methanol, i-PrOH: iso-propanol, NMR: nuclear magnetic resonance, MDR: multiple drug resistance, RPMI: Roswell Park Memorial Institute.

Oleanolic acid (OA) as an antileishmanial agent: Biological evaluation and in silico mechanistic insights.

Although a worldwide health problem, leishmaniasis is considered a highly neglected disease, lacking efficient and low toxic treatment. The efforts for new drug development are based on alternatives such as new uses for well-known drugs, in silico and synthetic studies and naturally derived compounds. Oleanolic acid (OA) is a pentacyclic triterpenoid widely distributed throughout the Plantae kingdom that displays several pharmacological activities. OA showed potent leishmancidal effects in different Leishmania species, both against promastigotes (IC(50 L. braziliensis) 30.47 ± 6.35 µM; IC(50 L. amazonensis) 40.46 ± 14.21 µM; IC(50 L. infantum) 65.93 ± 15.12 µM) and amastigotes (IC(50 L. braziliensis) 68.75 ± 16.55 µM; IC(50 L. amazonensis) 38.45 ± 12.05 µM; IC(50 L. infantum) 64.08 ± 23.52 µM), with low cytotoxicity against mouse peritoneal macrophages (CC(50) 235.80 ± 36.95 µM). Moreover, in silico studies performed to evaluate OA molecular properties and to elucidate the possible mechanism of action over the Leishmania enzyme sterol 14α-demethylase (CYP51) suggested that OA interacts efficiently with CYP51 and could inhibit the ergosterol synthesis pathway. Collectively, these data indicate that OA is a good candidate as leading compound for the development of a new leishmaniasis treatment.

3ß-Acetyl tormentic acid reverts MRP1/ABCC1 mediated cancer resistance through modulation of intracellular levels of GSH and inhibition of GST activity.

ABC transporter overexpression is an important mechanism of multidrug resistance (MDR) and one of the main obstacles to successful cancer treatment. As these proteins actively remove chemotherapeutics from the tumor cells, the pharmacological inhibition of their activity is a possible strategy to revert drug resistance. Moreover, the ability of MDR inhibitors to sensitize resistant cells to conventional drugs is important for their clinical use. Evidence has shown that the multidrug resistance protein 1 (MRP1/ABCC1) is a negative prognostic marker in patients with lung, gastric, or breast cancers or neuroblastoma. Previous data have shown that 3ß-acetyl tormentic acid (3ATA) inhibits the transport activity of the protein MRP1/ABCC1. In this study, we evaluated the ability of 3ATA to sensitize an MDR cell line (GLC4/ADR), which overexpresses MRP1, and investigated the anti-MRP1 mechanisms activated by 3ATA. The results showed that 3ATA is able to reverse the resistance of the MDR cell line to doxorubicin and vincristine, two drugs that are commonly used in cancer chemotherapy. Regarding the sensitizing mechanism induced by 3ATA, this work shows that the triterpene does not modulate the expression of MRP1/ABCC1 but is able to reduce total intracellular glutathione (GSH) levels and decrease the activity of glutathione-s-transferase (GST), the enzyme responsible for the glutathione conjugation of xenobiotics. Together, these results show that 3ATA sensitizes the MDR cell line overexpressing MRP1/ABCC1 to antineoplastic drugs and that this effect is mediated by the modulation of intracellular levels of GSH and GST activity.

Apoptosis-inducing effects of Melissa officinalis L. essential oil in glioblastoma multiforme cells.

Current therapies for glioblastoma multiforme (GBM) are not effective. This study investigated the activity of the M. officinalis essential oil (EO) and its major component (citral) in GBM cell lines. Both EO and citral decreased the viability and induced apoptosis of GBM cells as demonstrated by DNA fragmentation and caspase-3 activation. Antioxidant prevented citral-induced death, indicating its dependence on the production of reactive oxygen species. Citral downmodulated the activity and inhibited the expression of multidrug resistance associated protein 1 (MRP1). These results show that EO, through its major component, citral, may be of potential interest for the treatment of GBM.

Oleanolic acid improves pulmonary morphofunctional parameters in experimental sepsis by modulating oxidative and apoptotic processes.

We compared the effects of oleanolic acid (OA) vs. dexamethasone on lung mechanics and histology, inflammation, and apoptosis in lung and distal organs in experimental sepsis. Seventy-eight BALB/c mice were randomly divided into two groups. Sepsis was induced by cecal ligation and puncture, while the control group underwent sham surgery. 1h after surgery, all animals were further randomized to receive saline (SAL), OA and dexamethasone (DEXA) intraperitoneally. Both OA and DEXA improved lung mechanics and histology, which were associated with fewer lung neutrophils and less cell apoptosis in lung, liver, and kidney than SAL. However, only animals in the DEXA group had lower levels of interleukin (IL)-6 and KC (murine analog of IL-8) in bronchoalveolar lavage fluid than SAL animals. Conversely, OA was associated with lower inducible nitric oxide synthase expression and higher superoxide dismutase than DEXA. In the experimental sepsis model employed herein, OA and DEXA reduced lung damage and distal organ apoptosis through distinct anti-inflammatory mechanisms.

Effects of 3ß-acethyl tormentic acid (3ATA) on ABCC proteins activity.

Multidrug resistance (MDR) is considered the main cause of cancer chemotherapy failure and patient relapse. The active drug efflux mediated by transporter proteins of the ABC (ATP-binding cassette) family is the most investigated mechanism leading to MDR. With the aim of inhibiting this transport and circumventing MDR, a great amount of work has been dedicated to identifying pharmacological inhibitors of specific ABC transporters. We recently showed that 3ß-acetyl tormentic acid (3ATA) had no effect on P-gp/ABCB1 activity. Herein, we show that 3ATA strongly inhibited the activity of MRP1/ABCC1. In the B16/F10 and Ma104 cell lines, this effect was either 20X higher or similar to that observed with MK571, respectively. Nevertheless, the low inhibitory effect of 3ATA on A549, a cell line that expresses MRP1-5, suggests that it may not inhibit other MRPs. The use of cells transfected with ABCC2, ABCC3 or ABCC4 showed that 3ATA was also able to modulate these transporters, though with an inhibition ratio lower than that observed for MRP1/ABCC1. These data point to 3ATA as a new ABCC inhibitor and call attention to its potential use as a tool to investigate the function of MRP/ABCC proteins or as a co-adjuvant in the treatment of MDR tumors.

3ß-acetyl tormentic acid induces apoptosis of resistant leukemia cells independently of P-gp/ABCB1 activity or expression.

Chronic myeloid leukemia (CML) is a potentially fatal stem-cell cancer. P-glycoprotein (P-gp/ABCB1) activity has been described as a relevant factor in the chemotherapeutic failure and correlated to a poor prognosis in these malignancies. In the present study, we investigated the mechanism of the antineoplastic activity of 3ß-acetyl tormentic acid (3ATA), a triterpene isolated from C. lyratiloba, on Lucena-1, an MDR leukemia cell line, that overexpressed P-gp/ABCB1. Results showing that this triterpene induced DNA-fragmentation, activation of caspase-3 and cytochrome c release indicated that its activity is mediated by the activation of the intrinsic pathway of apoptosis. Interestingly, this triterpene did not interfere with P-gp/ABCB1 expression or activity, indicating that induction of death is not mediated by any effect on this protein. Moreover, the results show that none of the others triterpenes from C. lyratiloba were able to modulate the activity of P-gp/ABCB1. Together these results suggest 3ATA and the other triterpenes as a promising material for the development of anti-neoplastic drugs for leukemia and other tumors independent of P-gp/ABCB1 activity or expression.

Oleanolic acid initiates apoptosis in non-small cell lung cancer cell lines and reduces metastasis of a B16F10 melanoma model in vivo.

BACKGROUND: Drug resistance, a process mediated by multiple mechanisms, is a critical determinant for treating lung cancer. The aim of this study is to determine if oleanolic acid (OA), a pentacyclic triterpene present in several plants, is able to circumvent the mechanisms of drug resistance present in non-small cell lung cancer (NSCLC) cell lines and to induce their death. PRINCIPAL FINDINGS: OA decreased the cell viability of the NSCLC cell lines A459 and H460 despite the presence of active, multidrug-resistant (MDR) MRP1/ABCC1 proteins and the anti-apoptotic proteins Bcl-2 and survivin. These effects are due to apoptosis, as evidenced by the capacity of OA to induce fragmentation of DNA and activate caspase 3. Induction of NSCLC cell death by OA cannot be explained by inhibition of the MDR proteins, since treatment with triterpene had little or no effect on the activity or expression of MRP1. Moreover, treatment with OA had no effect on the expression of the anti-apoptotic protein Bcl-2, but increased the expression of the pro-apoptotic protein Bax, altering the Bcl-2/Bax balance towards a pro-apoptotic profile. OA also decreased the expression of the anti-apoptotic protein survivin. Furthermore, OA decreased the expression of the angiogenic vascular endothelial growth factor (VEGF) and decreased the development of melanoma-induced lung metastasis. CONCLUSION: Our data provide a significant insight into the antitumoral and antimetastatic activity of OA in NSCLC and suggest that including OA in the NSCLC regimens may help to decrease the number of relapses and reduce the development of metastases.

Betulinic acid does not modulate the activity of P-gp/ABCB1 or MRP1/ABCC1 in a non-tumoral renal cell line: Possible utility in multidrug resistance cancer chemotherapy.

Multidrug resistance (MDR) is a multifactorial phenomenon considered to be the main cause of failure in cancer chemotherapy. One of the underlying mechanisms of MDR is the overexpression of membrane transporter proteins, such as P-glycoprotein (P-gp/ABCB1) and multidrug resistance-associated protein 1 (MRP1/ABCC1). As these proteins are also expressed in normal tissues, considerable attention has been dedicated to the search for cytotoxic drugs that are not substrates for these proteins. This study investigated the effects of betulinic acid (BA) on the activity of ABCB1 and ABCC1 in Ma-104, a non-tumoral renal cell line constitutively expressing both proteins. The results indicated that concentrations of BA with low cytotoxicity to Ma-104 did not alter the activity of ABCB1 or ABCC1, nor did BA interfere with the accumulation of a classic chemotherapeutic, methotrexate. This suggests it would also be a good choice for use in drug cocktails. The lack of effect of BA on ABCB1 and ABCC1, as well as its antitumoral properties, suggest that this triterpene is a viable chemotherapeutic agent for MDR tumors.

Ras pathway activation in gliomas: a strategic target for intranasal administration of perillyl alcohol.

INTRODUCTION: Targeted therapy directed at specific molecular alterations is already creating a shift in the treatment of cancer patients. Malignant gliomas commonly overexpress the oncogenes EGFR and PDGFR and contain mutations and deletions of the tumor suppressor genes PTEN and TP53. Some of these alterations lead to activation of the P13K/Akt and Ras/MAPK pathways, which provide targets for therapy. Perillyl alcohol (POH), the isoprenoid of greatest clinical interest, was initially considered to inhibit farnesyl protein transferase. Follow-up studies revealed that POH suppresses the synthesis of small G proteins, including Ras. Intranasal delivery allows drugs that do not cross the blood-brain barrier to enter the central nervous system. Moreover, it eliminates the need for systemic delivery, thereby reducing unwanted systemic side effects. MATERIALS AND METHODS: Applying this method, a phase I/II clinical trial of POH was performed in patients with relapsed malignant gliomas after standard treatment: surgery, radiotherapy, and chemotherapy. POH was administrated in a concentration of 0.3% volume/volume (55 mg) four times daily in an interrupted administration schedule. The objective was to evaluate toxicity and progression-free survival (PFS) after six months of treatment. The cohort consisted of 37 patients, including 29 with glioblastoma multiforme (GBM), 5 with grade III astrocytoma (AA), and 3 with anaplastic oligodendroglioma (AO). Neurological examination and suitable image analysis (computed tomography (CT), magnetic resonance imaging (MRI)) established disease progression. Complete response was defined as neurological stability or improvement of conditions, disappearance of CT/MRI tumor image, and corticosteroid withdraw; partial response (PR) as > or =50 reduction of CT/MRI tumor image, neurological stability, or improvement of conditions and corticosteroid requirement; progressive course (PC) as > or =25 increase in CT/MRI tumor image or the appearance of a new lesion; and stable disease as a lack of any changes in the CT/MR tumor image or neurological status. RESULTS: After six months of treatment, PR was observed in 3.4% (n=1) of the patients with GBM and 33.3% (n=1) with AO; stable disease in 44.8% (n=13) with GBM, 60% (n=3) with AA, and 33.3% (n=1) with AO; and PC in 51.7% (n=15) with GBM, 40% (n=2), with AA and 33.3% (n=1) AO. PFS (sum of PRs and stable disease) was 48.2% for GBM, 60% for AA, and 66.6% for AO patients. CONCLUSIONS: The preliminary results indicate that intranasal administration of the signal transduction inhibitor POH is a safe, noninvasive, and low-cost method. There were no toxicity events and the regression of tumor size in some patients is suggestive of antitumor activity.

Antitumoral activity of new polyamine-naphthoquinone conjugates.

Polyamine-naphthoquinone conjugates 5a-c were synthesized by nucleophilic displacement of 2-methoxy-lawsone 3a, 2-methoxylapachol 3b and 2-methoxy-nor-lapachol 3c with the polyamine N1-Boc-N5-Bn-spermidine 4. Unprotected derivatives 6a-c were synthesized to evaluate the effect of the protective Boc group on the activity of compounds 5a-c. The colorimetric MTT assay was used to evaluate their cytotoxic activity. All compounds were active against human lines of promyelocytic leukemia (HL-60), lung cancer (GLC4), Burkitt lymphoma (Daudi) and a mouse breast tumor (Ehrlich carcinoma), but only unprotected 6a-c showed activity against the human line of melanoma (MV-3). IC50 values were obtained from dose response curves by linear regression. DNA fragmentation was measured by quantification of the subG1 peak of the cell cycle. Apoptosis of HL-60 treated with 5c was dose-dependent. The amount of DNA fragmentation observed by exposure of HL-60 to 25 microM of compounds 5a-c and 6a-c is compatible with the decrease in viability induced by the drugs at this concentration. Production of ROS was measured by H2-CFDA. Kinetics of HL-60 DNA fragmentation and ROS formation by 5c indicated that production of ROS precedes cell death. In conclusion, spermidine-1,4-naphthoquinone conjugates exhibited an increase in activity compared with the natural products and induced apoptosis of tumor cell lines by a mechanism that is mediated, at least in part, by ROS production.

Análise de metaloproteases de matriz extracelular como indicador prognóstico nos gliomas malignos / Analysis of matrix metalloproteinase as prognostic indicator in malignant gliomas

Introdução: Metaloproteases de matriz extracelular(MMP) são enzimas proteolíticas sintetizadas na fase de fenótipo mais agressivo dos gliomas malignos, degradando proteínas da matriz extracelular,ocasionando ruptura da barreira hematoencefálica e contribuindo para a resposta neuroinflamatória,angiogênese e migração.Estudos mostram expressão de gelatinase A(MMP-2)proeminentemente nas células gliais tumorais,com pouca expressão na microvasculatura,enquanto expressão de gelatinase B(MMP-9)é proeminente na microvasculatrua, com porco sinal nas células tumorais.Objetivo:Neste estudo analisamos amostras de soro de 34 pacientes com gliomas malignos recidivos,antes e durante o tratamento com álcool perílico por via inalatória para determinar se a expressão de MMP poderia ser usada como indicador prognóstico.Métodos:A atividade gelatinade (MMP-2, MMP-9)nas amostras de soro foi determinada por zimografia e a atividade enzimática relativa foi determinada utilizando-se programa de análise densitométrica.Os valores foram correlacionados com exames de imagem e sobrevida dos pacientes. Resultados:Os resultados obtidos em nosso estudo evidenciaram que os pacientes com gliomas malignos apresentaram aumento da expressão de MMP-2 e MMP-9 quando comparados com pacientes saudáveis.Expressão aumentada de MMP-2 foi proporcional à progressão tumoral,sobrevida desfavorável e área de edema peritumoral.Conclusão:Esses resultados indicam proporcionalidade entre a expressão de MMP-2 e a malignidade dos gliomas, sugerindo seu emprego como indicador prognóstico para recorrência tumoral pós-operatória e sobrevida desfavorável dos pacientes.

Preliminary results from a phase I/II study of perillyl alcohol intranasal administration in adults with recurrent malignant gliomas.

BACKGROUND: Activation of the p21-ras signaling pathway from aberrantly expressed receptors promotes the growth of malignant human astrocytomas. Perillyl alcohol has shown to have both chemopreventive and chemotherapeutic activities in preclinical studies. The underlying action mechanism(s) of POH has yet to be delineated but may involve effects on the TGF-beta and/or the Ras signaling pathways. The intranasal delivery allows drugs that do not cross the BBB to enter the CNS; moreover, it eliminates the need for systemic delivery, thereby reducing unwanted systemic side effects. METHODS: We are conducting a phase I/II study to evaluate the antitumoral activity of POH intranasal delivery in a 4x daily schedule in patients with recurrent MG. The objective was to determine PFS at 6 months and the safety for POH in adult patients who failed conventional treatment. Assessments were performed every 27 days. Thirty-seven patients with progressive disease after prior surgery, radiotherapy, and at least temozolomide-based chemotherapy were enrolled, 29 of whom had GBM, 5 who had anaplastic astrocytoma, and 3 had AO. RESULTS: One patient (3.4%) with GBM and 1 patient (33.3%) with AO achieved partial response; 13 patients (44.8%) with GBM, 3 patients (60%) with AA, and 1 (33.3%) with AO achieved stable disease; 15 (51.7%) patients with GBM, 2 (40%) patients with AA, and 1 (33.3%) with AO showed progressive disease. Progression-free survival (partial response and stable disease) was 48.2% for patients with GBM, 60% for patients with AA, and 66.6% for patients with AO. CONCLUSIONS: There were no toxicity events. Perillyl alcohol is well tolerated and regression of tumor size in some patients is suggestive of antitumor activity. This work discusses POH intranasal delivery as a potential adjuvant therapeutic strategy for patients with malignant gliomas.

Natural triterpenoids from Cecropia lyratiloba are cytotoxic to both sensitive and multidrug resistant leukemia cell lines.

The cytotoxicity of four triterpenoids, euscaphic acid (1), tormentic acid (2), 2alpha-acetyl tormentic acid (3), and 3beta-acetyl tormentic acid (4), isolated from the roots of Cecropia lyratiloba (Moraceae) by countercurrent chromatography, was evaluated in vitro in sensitive and multidrug resistant leukemia cell lines. A structure/activity relationship analysis of the compounds was performed. Acetylation of compound 2 at C2 increased its activity by a factor of 2 while acetylation at C3 had a smaller effect. Compound 1 induces death by activation of caspase-3, dependent apoptotic pathway. Furthermore, the four triterpenoids were also active toward a multidrug resistant (MDR) leukemia cell line, overexpressing glycoprotein-P (P-gp). These results reveal the potential of the terpenoids as source for the development of new anti-neoplastic and anti-MDR drugs.

Detecção imuno-histoquímica de células apoptóticas em glioblastoma recidivante de paciente tratado com álcool perílico por via inalatória / Immunohistochemical detection of apoptotic cells in a recurrent glioblastoma patient treated with intranasal delivery of perillyl alcohol

Introdução: Estudos in vitro mostram que radioterapia e/ou quimioterapia podem ativar as vias de sinalizaçãodo receptor do fator de crescimento epidérmico (EGFR) e Ras, aumentando a resistência cruzada dascélulas de glioblastomas multiformes (GBM) ao tratamento. A inibição das atividades de EGFR e Rasatravés de inibidores tirosinas cinases elimina o antagonismo observado à administração seqüencialdestas modalidades terapêuticas, induzindo apoptose nestas células. Em estudo prévio demonstramosque o tratamento com o álcool perílico (AP), inibidor da farnesilação da Ras, induz apoptose em linhagenscelulares e células de explante de GBM. Objetivo: No presente estudo investigamos se a regressãoparcial observada em GBM recorrente de paciente tratado com administração intranasal de AP é mediadapor apoptose. Resultado: Ensaios com TUNEL (deoxynucleotidyl-mediated deoxyuridine triphosphate) ecaspase-3 ativada evidenciaram presença de células apoptóticas nas lâminas de GBM tratado. Conclusão:Esses achados sugerem que estratégias adjuvantes visando à inativação das vias de sinalização do EGFRe Ras podem melhorar tanto a eficácia de terapia isolada como de terapia multimodal em gliomas.

Background: In vitro studies demonstrated that both radiation and chemotherapy can activate EGFRand Ras signaling pathways, leading to increased cross-resistance to treatment of GBM cell. Inhibition of either EGFR or Ras activity with tytosine kinase inhibitor appears to abrogate the observed antagonism between sequentially administration of these therapeutic modalities inducing apoptosis in these cells. In a previous study, we demonstrated that in vitro treatment with perillyl alcohol (POH), an inhibitor of Ras farnezilation, induced apoptosis in human GBM cell lines and explants. Objective: In the presentstudy, we investigated if the partial regression observed in a patient with a recurrent GBM after treatmentby intranasal delivery of POH, is mediated by apoptosis. Result: Data from classical histology, terminaldeoxynucleotidyl-mediated deoxyuridine triphosphate nick-end labeling (TUNEL) assay, as well asactivation of caspase 3, showed increased apoptosis in the treated tumor. Conclusion: These findings suggest that strategies to inactivate EGFR and RAS signaling may be critical to improving not only theefficacy of single-agent therapy but also of multimodal therapy in gliomas.

Pomolic acid may overcome multidrug resistance mediated by overexpression of anti-apoptotic Bcl-2 proteins.

Multidrug resistance (MDR) is multifactorial and may be mediated by overexpression of anti-apoptotic proteins. This paper investigated whether pomolic acid (PA) was able to overcome resistance mediated by overexpression of Bcl-2 or BcL-xL. The results obtained showed that overexpression of these proteins partially inhibited the PA-induced apoptosis, loss of mitochondrial membrane potential and caspase -3 and -9 activation observed in HL-60/neo. Since Bcl-2 transfected cell lines were shown to be quite resistant to a series of chemotherapeutic agents, the data presented call attention to the possible clinical significance of PA as an anti-MDR drug.

Estudo exploratório da administração intranasal do monoterpeno álcool perílico em pacientes com glioma recidivante / Exploratory study of monoterpene perillylalcohol intranasal administration in patients with recurrent gliomas

Objetivo: Conduzimos estudo de fase I/II para avaliar atividade antitumoral do álcool perílico (AP) por via inalatória em pacientes com gliomas recidivantes. Pacientes e Métodos: Trinta e sete pacientes com glioma recidivante após tratamento convencional foram matriculados, dos quais 29 com glioblastoma (GBM), 5 com astrocitoma anaplásico (AA) e 3 com oligodendroglioma anaplásico (OA). O objetivo foi determinar a sobrevida livre de progressão no 6º mês e a toxicidade do AP administrado 4 vezes ao dia em pacientes refratários ao tratamento convencional. Resultados: Os resultados mostraram no 6º mês de tratamento, resposta parcial em 1 paciente (3,4%) com GBM e 1 paciente (33,3%) com OA; doença estável em 13 pacientes (44,8%) com GBM, 3 pacientes (60%) com AA e 1 paciente (33,3%) com OA; progressão da doença em 15 pacientes (51,7%) com GBM, 2 pacientes (40%) com AA e 1 paciente (33,3%) com OA. A sobrevida livre de progressão (somatório de resposta parcial e doença estável) foi de 48,2% para pacientes com GBM, 60% para pacientes com AA e 66,6% para pacientes com OA. Conclusão: O presente trabalho mostrou pela primeira vez, que a administração intranasal de um inibidor da transdução do sinal, álcool perílico, é uma estratégia segura, não invasiva, de baixo custo, e a regressão do volume tumoral em alguns pacientes é sugestivo de atividade antitumoral.

Objective: A phase I/II study to evaluate the antitumoral activity of perillyl alcohol (POH) intranasal delivery in patients with recurrent gliomas was conducted. Patients and Methods: Thirty-seven patients with recurrent gliomas after standard therapy were enrolled, of whom 29 presented with glioblastoma (GBM), 5 with anaplastic astrocytoma (AA), and 3 with anaplastic oligodendroglioma (AO). The objective was to determine progression-free survival at 6 months and the safety for POH in a 4 x daily schedule in patients who failed conventional treatment. Results: After 6 months of treatment the fol¬lowing was observed: Partial Response: 3.4% (n=1) with GBM and 33,3% (n=1) with AO; Stable Disease: 44.8% (n=13) with GBM, 60% (n=3) with AA and 33.3% (n=1) with AO; Progressive Course: 51.7% (n= 15) with GBM, 40% (n=2) with AA and 33.3% (n=1) AO. The progression free survival (sum of partial responses and stable disease) was 48.2% for patients with GBM, 60%, for AA patients and 66.6% for AO patients. Conclusion: The present work indicates, for the first time, that intranasal administration of the signal transduction inhibitor, perillyl alcohol, is a safe, non- invasive, low cost treatment and that regres¬sion of tumor size in some patients is suggestive of antitumoral activity.

Anaplastic oligodendroglioma responding favorably to intranasal delivery of perillyl alcohol: a case report and literature review.

BACKGROUND: In recent years, molecular genetics and biology are exerting significant influence on the practice of neuro-oncology, with oligodendrogliomas being the most prominent example. To explore therapeutic strategies and evaluate the clinical results, we report a case of a patient with anaplastic oligodendroglioma managed with intranasal delivery of POH. CASE DESCRIPTION: A 62 year-old white woman presented with complaints of seizures and frontal headache in June 1999. Nervous system examination was normal. Her Karnofsky performance score was 90. A contrast-enhanced MRI scan of the brain revealed a regular space-occupying lesion in the right frontal lobe that enhanced with gadolinium. A radical surgical excision of the tumor was carried out, and the histopathological diagnosis was an anaplastic oligodendroglioma. Subsequently, there were 2 recurrent/progressive lesions, in July 2002 and October 2004, despite combination treatment using surgery, radiotherapy, and chemotherapy. Intranasal delivery of 0.3% concentration of POH 4 times daily was performed. A follow-up MRI scan after 5 months of treatment revealed reduction in size of the enhancing lesion. CONCLUSION: Whereas surgery continues to be the primary treatment for oligodendroglioma, the scheme for postoperative therapy has shifted primarily because of the lesion's relative chemosensitivity. This article evaluates the effects of intranasal delivery of POH in a case of regression of anaplastic oligodendroglioma.