GOLPH3 Participates in Mitochondrial Fission and Is Necessary to Sustain Bioenergetic Function in MDA-MB-231 Breast Cancer Cells

In this study, we investigated the inter-organelle communication between the Golgi apparatus (GA) and mitochondria. Previous observations suggest that GA-derived vesicles containing phosphatidylinositol 4-phosphate (PI(4)P) play a role in mitochondrial fission, colocalizing with DRP1, a key protein in this process. However, the functions of these vesicles and potentially associated proteins remain unknown. GOLPH3, a PI(4)P-interacting GA protein, is elevated in various types of solid tumors, including breast cancer, yet its precise role is unclear. Interestingly, GOLPH3 levels influence mitochondrial mass by affecting cardiolipin synthesis, an exclusive mitochondrial lipid. However, the mechanism by which GOLPH3 influences mitochondria is not fully understood. Our live-cell imaging analysis showed GFP-GOLPH3 associating with PI(4)P vesicles colocalizing with YFP-DRP1 at mitochondrial fission sites. We tested the functional significance of these observations with GOLPH3 knockout in MDA-MB-231 cells of breast cancer, resulting in a fragmented mitochondrial network and reduced bioenergetic function, including decreased mitochondrial ATP production, mitochondrial membrane potential, and oxygen consumption. Our findings suggest a potential negative regulatory role for GOLPH3 in mitochondrial fission, impacting mitochondrial function and providing insights into GA-mitochondria communication.

Defective insulin-stimulated equilibrative nucleoside transporter-2 activity and altered subcellular transporter distribution drive the loss of adenosine homeostasis in diabetic kidney disease progression

AIM

Progression of diabetic nephropathy (DN) is linked to the dysregulated increase of adenosine and altered signaling properties. A major contribution to the maintenance of physiological extracellular adenosine levels relies on cellular uptake activity through plasma membrane nucleoside transporters. Because kidney cells are responsive to insulin, this study aims to determine how DN affects insulin regulation of the equilibrative nucleoside transporter-2 (ENT2).

METHODS

Human Podocytes and rat glomeruli were used to study ENT2 regulation. The effects of diabetes and insulin on ENT2 mediated transport activity were determined measuring the fraction of total adenosine uptake in sodium-free medium which is inhibitable by hypoxanthine. Alterations in ENT2 subcellular distribution were assessed in the kidney of people affected with DN and diabetic rats. The consequences of impaired ENT2 activity on the kidney were evaluated using dipyridamole in an animal model.

RESULTS

Insulin upregulates ENT2 uptake activity by increasing the Vmax, thus counteracting decreased adenosine uptake due to high d-glucose and achieving extracellular adenosine homeostasis. Insulin promoted ENT2 translocation to the plasma membrane dependent on PI3-kinase/Akt signaling and actin cytoskeleton integrity. However, in diabetic rats, the insulin-mediated induction of ENT2 activity was lost. Additionally, reduced Akt activation in response to insulin correlated with decreased ENT2 distribution at the plasma membrane. Kidney tissues from diabetic rats and human DN biopsies showed ENT2 redistribution to an intracellular pattern, evidencing dysfunctional adenosine uptake. Through ENT inhibition, we evidenced increased proteinuria and induced alpha-smooth muscle actin as a result of profibrotic activation of cells in the kidney.

CONCLUSION

Deficient insulin regulation of ENT2 activity contributes to chronically high adenosine levels and glomerular alterations that underline diabetic kidney disease progression.

Long-term social isolation stress exacerbates sex-specific neurodegeneration markers in a natural model of Alzheimer's disease

Social interactions have a significant impact on health in humans and animal models. Social isolation initiates a cascade of stress-related physiological disorders and stands as a significant risk factor for a wide spectrum of morbidity and mortality. Indeed, social isolation stress (SIS) is indicative of cognitive decline and risk to neurodegenerative conditions, including Alzheimer's disease (AD). This study aimed to evaluate the impact of chronic, long-term SIS on the propensity to develop hallmarks of AD in young degus (Octodon degus), a long-lived animal model that mimics sporadic AD naturally. We examined inflammatory factors, bioenergetic status, reactive oxygen species (ROS), oxidative stress, antioxidants, abnormal proteins, tau protein, and amyloid-β (Aβ) levels in the hippocampus of female and male degus that were socially isolated from post-natal and post-weaning until adulthood. Additionally, we explored the effect of re-socialization following chronic isolation on these protein profiles. Our results showed that SIS promotes a pro-inflammatory scenario more severe in males, a response that was partially mitigated by a period of re-socialization. In addition, ATP levels, ROS, and markers of oxidative stress are severely affected in female degus, where a period of re-socialization fails to restore them as it does in males. In females, these effects might be linked to antioxidant enzymes like catalase, which experience a decline across all SIS treatments without recovery during re-socialization. Although in males, a previous enzyme in antioxidant pathway diminishes in all treatments, catalase rebounds during re-socialization. Notably, males have less mature neurons after chronic isolation, whereas phosphorylated tau and all detectable forms of Aβ increased in both sexes, persisting even post re-socialization. Collectively, these findings suggest that long-term SIS may render males more susceptible to inflammatory states, while females are predisposed to oxidative states. In both scenarios, the accumulation of tau and Aβ proteins increase the individual susceptibility to early-onset neurodegenerative conditions such as AD.

A2BAR Antagonism Decreases the Glomerular Expression and Secretion of Chemoattractants for Monocytes and the Pro-Fibrotic M2 Macrophages Polarization during Diabetic Nephropathy

Some chemoattractants and leukocytes such as M1 and M2 macrophages are known to be involved in the development of glomerulosclerosis during diabetic nephropathy (DN). In the course of diabetes, an altered and defective cellular metabolism leads to the increase in adenosine levels, and thus to changes in the polarity (M1/M2) of macrophages. MRS1754, a selective antagonist of the A2B adenosine receptor (A2BAR), attenuated glomerulosclerosis and decreased macrophage-myofibroblast transition in DN rats. Therefore, we aimed to investigate the effect of MRS1754 on the glomerular expression/secretion of chemoattractants, the intraglomerular infiltration of leukocytes, and macrophage polarity in DN rats. Kidneys/glomeruli of non-diabetic, DN, and MRS1754-treated DN rats were processed for transcriptomic analysis, immunohistopathology, ELISA, and in vitro macrophage migration assays. The transcriptomic analysis identified an upregulation of transcripts and pathways related to the immune system in the glomeruli of DN rats, which was attenuated using MRS1754. The antagonism of the A2BAR decreased glomerular expression/secretion of chemoattractants (CCL2, CCL3, CCL6, and CCL21), the infiltration of macrophages, and their polarization to M2 in DN rats. The in vitro macrophages migration induced by conditioned-medium of DN glomeruli was significantly decreased using neutralizing antibodies against CCL2, CCL3, and CCL21. We concluded that the pharmacological blockade of the A2BAR decreases the transcriptional expression of genes/pathways related to the immune response, protein expression/secretion of chemoattractants, as well as the infiltration of macrophages and their polarization toward the M2 phenotype in the glomeruli of DN rats, suggesting a new mechanism implicated in the antifibrotic effect of MRS1754.

Mitochondrial Bioenergetics, Redox Balance, and Calcium Homeostasis Dysfunction with Defective Ultrastructure and Quality Control in the Hippocampus of Aged Female C57BL/6J Mice

Aging is a physiological process that generates progressive decline in many cellular functions. There are many theories of aging, and one of great importance in recent years is the mitochondrial theory of aging, in which mitochondrial dysfunction that occurs at advanced age could be responsible for the aged phenotype. In this context, there is diverse information about mitochondrial dysfunction in aging, in different models and different organs. Specifically, in the brain, different studies have shown mitochondrial dysfunction mainly in the cortex; however, until now, no study has shown all the defects in hippocampal mitochondria in aged female C57BL/6J mice. We performed a complete analysis of mitochondrial function in 3-month-old and 20-month-old (mo) female C57BL/6J mice, specifically in the hippocampus of these animals. We observed an impairment in bioenergetic function, indicated by a decrease in mitochondrial membrane potential, O2 consumption, and mitochondrial ATP production. Additionally, there was an increase in ROS production in the aged hippocampus, leading to the activation of antioxidant signaling, specifically the Nrf2 pathway. It was also observed that aged animals had deregulation of calcium homeostasis, with more sensitive mitochondria to calcium overload and deregulation of proteins related to mitochondrial dynamics and quality control processes. Finally, we observed a decrease in mitochondrial biogenesis with a decrease in mitochondrial mass and deregulation of mitophagy. These results show that during the aging process, damaged mitochondria accumulate, which could contribute to or be responsible for the aging phenotype and age-related disabilities.

Exploring the destiny and distribution of thiocyanate in the water-soil-plant system and the potential impacts on human health

Endocrine disruptors like thiocyanate are some of the principal causes of chronic disorders worldwide. Prenatal and postnatal exposure to thiocyanate can interfere with normal neurological development in both fetuses and newborns. Currently, little information regarding thiocyanate levels and potential sources of exposure is available. In this study, we evaluated thiocyanate uptake and accumulation in chard and spinach grown under greenhouse conditions. Both chard and spinach are commonly used to produce baby foods. Three thiocyanate concentrations were compared: Control, T1 (30 ng mL^-1), and T2 (70 ng mL^-1). Thiocyanate accumulation depended on the concentration and exposure time. Chard was found to accumulate more thiocyanate than spinach, with leaf accumulation > stem accumulation (p < 0.0194) and maximum concentrations of 76 ng g^-1 (control), 112 ng g^-1, (T1), and 134 ng g^-1 (T2). The estimated daily intake (EDI) of thiocyanate for chard and spinach (fresh) exceeded the subchronic reference dose of 200 ng^-1 kg^-1 day^-1 and the chronic reference dose of 600 ng^-1 kg^-1 day^-1. In addition, the EDI of thiocyanate for spinach in baby food exceeded twice the chronic reference dose in the vulnerable newborn-1 year age group. However, all EDIs were lower than the lowest observed adverse effect level (LOAEL) of 1.9 × 10⁵ ng kg^-1 day^-1. Further studies are needed that increase our knowledge of thiocyanate levels and potential environmental sources to reduce opportunities for exposure, especially in vulnerable groups.

Accumulation and distribution of perchlorate in spinach and chard growing under greenhouse: Implications for food safety in baby foods commodities

Very little information is available with regards to the bioavailability of perchlorate in spinach or chard used in the production of baby foods commodities. In the present study, the uptake and accumulation of perchlorate were compared under two different treatments (T1: 1 and T2: 10 mg L^-1 ClO₄^-). Our results indicate that spinach has a higher capacity to accumulate perchlorate than chard (p < 0.0185). Concentrations of perchlorate in leaves, stems and roots (leaves > stem > roots) all gradually increased (p < 0.0001) as vegetable growing and treatment (T2 > T1). No significant differences were found between the control and T1. The daily intake for perchlorate (control) is below the proposed international standard, however, it was exceeded in T1 and T2. The results suggested that perchlorate is actively accumulate in high concentrations in vegetables used in the production of baby food commodities and the exposure of perchlorate via the food consumption (baby foods) was evaluated as not safe.

Phosphorylated tau as a toxic agent in synaptic mitochondria: implications in aging and Alzheimer's disease

During normal aging, there is a decline in all physiological functions in the organism. One of the most affected organs is the brain, where neurons lose their proper synaptic function leading to cognitive impairment. Aging is one of the main risk factors for the development of neurodegenerative diseases, such as Alzheimer’s disease. One of the main responsible factors for synaptic dysfunction in aging and neurodegenerative diseases is the accumulation of abnormal proteins forming aggregates. The most studied brain aggregates are the senile plaques, formed by Aβ peptide; however, the aggregates formed by phosphorylated tau protein have gained relevance in the last years by their toxicity. It is reported that neurons undergo severe mitochondrial dysfunction with age, with a decrease in adenosine 5′-triphosphate production, loss of the mitochondrial membrane potential, redox imbalance, impaired mitophagy, and loss of calcium buffer capacity. Interestingly, abnormal tau protein interacts with several mitochondrial proteins, suggesting that it could induce mitochondrial dysfunction. Nevertheless, whether tau-mediated mitochondrial dysfunction occurs indirectly or directly is still unknown. A recent study of our laboratory shows that phosphorylated tau at Ser396/404 (known as PHF-1), an epitope commonly related to pathology, accumulates inside mitochondria during normal aging. This accumulation occurs preferentially in synaptic mitochondria, which suggests that it may contribute to the synaptic failure and cognitive impairment seen in aged individuals. Here, we review the main tau modifications promoting mitochondrial dysfunction, and the possible mechanism involved. Also, we discuss the evidence that supports the possibility that phosphorylated tau accumulation in synaptic mitochondria promotes synaptic and cognitive impairment in aging. Finally, we show evidence and argue about the presence of phosphorylated tau PHF-1 inside mitochondria in Alzheimer’s disease, which could be considered as an early event in the neurodegenerative process. Thus, phosphorylated tau PHF-1 inside the mitochondria could be considered such a potential therapeutic target to prevent or attenuate age-related cognitive impairment.

Synaptic Mitochondria: An Early Target of Amyloid-β and Tau in Alzheimer's Disease

Alzheimer's disease (AD) is characterized by cognitive impairment and the presence of neurofibrillary tangles and senile plaques in the brain. Neurofibrillary tangles are composed of hyperphosphorylated tau, while senile plaques are formed by amyloid-β (Aβ) peptide. The amyloid hypothesis proposes that Aβ accumulation is primarily responsible for the neurotoxicity in AD. Multiple Aβ-mediated toxicity mechanisms have been proposed including mitochondrial dysfunction. However, it is unclear if it precedes Aβ accumulation or if is a consequence of it. Aβ promotes mitochondrial failure. However, amyloid β precursor protein (AβPP) could be cleaved in the mitochondria producing Aβ peptide. Mitochondrial-produced Aβ could interact with newly formed ones or with Aβ that enter the mitochondria, which may induce its oligomerization and contribute to further mitochondrial alterations, resulting in a vicious cycle. Another explanation for AD is the tau hypothesis, in which modified tau trigger toxic effects in neurons. Tau induces mitochondrial dysfunction by indirect and apparently by direct mechanisms. In neurons mitochondria are classified as non-synaptic or synaptic according to their localization, where synaptic mitochondrial function is fundamental supporting neurotransmission and hippocampal memory formation. Here, we focus on synaptic mitochondria as a primary target for Aβ toxicity and/or formation, generating toxicity at the synapse and contributing to synaptic and memory impairment in AD. We also hypothesize that phospho-tau accumulates in mitochondria and triggers dysfunction. Finally, we discuss that synaptic mitochondrial dysfunction occur in aging and correlates with age-related memory loss. Therefore, synaptic mitochondrial dysfunction could be a predisposing factor for AD or an early marker of its onset.

Pathologically phosphorylated tau at S396/404 (PHF-1) is accumulated inside of hippocampal synaptic mitochondria of aged Wild-type mice

Brain aging is a natural process characterized by cognitive decline and memory loss. This impairment is related to mitochondrial dysfunction and has recently been linked to the accumulation of abnormal proteins in the hippocampus. Age-related mitochondrial dysfunction could be induced by modified forms of tau. Here, we demonstrated that phosphorylated tau at Ser 396/404 sites, epitope known as PHF-1, is increased in the hippocampus of aged mice at the same time that oxidative damage and mitochondrial dysfunction are observed. Most importantly, we showed that tau PHF-1 is located in hippocampal mitochondria and accumulates in the mitochondria of old mice. Finally, since two mitochondrial populations were found in neurons, we evaluated tau PHF-1 levels in both non-synaptic and synaptic mitochondria. Interestingly, our results revealed that tau PHF-1 accumulates primarily in synaptic mitochondria during aging, and immunogold electron microscopy and Proteinase K protection assays demonstrated that tau PHF-1 is located inside mitochondria. These results demonstrated the presence of phosphorylated tau at PHF-1 commonly related to tauopathy, inside the mitochondria from the hippocampus of healthy aged mice for the first time. Thus, this study strongly suggests that synaptic mitochondria could be damaged by tau PHF-1 accumulation inside this organelle, which in turn could result in synaptic mitochondrial dysfunction, contributing to synaptic failure and memory loss at an advanced age.

Tau Deletion Prevents Cognitive Impairment and Mitochondrial Dysfunction Age Associated by a Mechanism Dependent on Cyclophilin-D

Aging is an irreversible process and the primary risk factor for the development of neurodegenerative diseases, such as Alzheimer’s disease (AD). Mitochondrial impairment is a process that generates oxidative damage and ATP deficit; both factors are important in the memory decline showed during normal aging and AD. Tau is a microtubule-associated protein, with a strong influence on both the morphology and physiology of neurons. In AD, tau protein undergoes post-translational modifications, which could play a relevant role in the onset and progression of this disease. Also, these abnormal forms of tau could be present during the physiological aging that could be related to memory impairment present during this stage. We previously showed that tau ablation improves mitochondrial function and cognitive abilities in young wild-type mice. However, the possible contribution of tau during aging that could predispose to the development of AD is unclear. Here, we show that tau deletion prevents cognitive impairment and improves mitochondrial function during normal aging as indicated by a reduction in oxidative damage and increased ATP production. Notably, we observed a decrease in cyclophilin-D (CypD) levels in aged tau−/− mice, resulting in increased calcium buffering and reduced mitochondrial permeability transition pore (mPTP) opening. The mPTP is a mitochondrial structure, whose opening is dependent on CypD expression, and new evidence suggests that this could play an essential role in the neurodegenerative process showed during AD. In contrast, hippocampal CypD overexpression in aged tau−/− mice impairs mitochondrial function evidenced by an ATP deficit, increased mPTP opening, and memory loss; all effects were observed in the AD pathology. Our results indicate that the absence of tau prevents age-associated cognitive impairment by maintaining mitochondrial function and reducing mPTP opening through a CypD-dependent mechanism. These findings are novel and represent an important advance in the study of how tau contributes to the cognitive and mitochondrial failure present during aging and AD in the brain.

Palmitic acid reduces the autophagic flux in hypothalamic neurons by impairing autophagosome-lysosome fusion and endolysosomal dynamics

High-fat diet (HFD)-induced obesity is associated with increased cancer risk. Long-term feeding with HFD increases the concentration of the saturated fatty acid palmitic acid (PA) in the hypothalamus. We previously showed that, in hypothalamic neuronal cells, exposure to PA inhibits the autophagic flux, which is the whole autophagic process from the synthesis of the autophagosomes, up to their lysosomal fusion and degradation. However, the mechanism by which PA impairs autophagy in hypothalamic neurons remains unknown. Here, we show that PA-mediated reduction of the autophagic flux is not caused by lysosomal dysfunction, as PA treatment does not impair lysosomal pH or the activity of cathepsin B.Instead, PA dysregulates autophagy by reducing autophagosome-lysosome fusion, which correlates with the swelling of endolysosomal compartments that show areduction in their dynamics. Finally, because lysosomes undergo constant dynamic regulation by the small Rab7 GTPase, we investigated the effect of PA treatment on its activity. Interestingly, we found PA treatment altered the activity of Rab7. Altogether, these results unveil the cellular process by which PA exposure impairs the autophagic flux. As impaired autophagy in hypothalamic neurons promotes obesity, and balanced autophagy is required to inhibit malignant transformation, this could affect tumor initiation, progression, and/or response to therapy of obesity-related cancers.

Premature synaptic mitochondrial dysfunction in the hippocampus during aging contributes to memory loss

Aging is a process characterized by cognitive impairment and mitochondrial dysfunction. In neurons, these organelles are classified as synaptic and non-synaptic mitochondria depending on their localization. Interestingly, synaptic mitochondria from the cerebral cortex accumulate more damage and are more sensitive to swelling than non-synaptic mitochondria. The hippocampus is fundamental for learning and memory, synaptic processes with high energy demand. However, it is unknown if functional differences are found in synaptic and non-synaptic hippocampal mitochondria; and whether this could contribute to memory loss during aging. In this study, we used 3, 6, 12 and 18 month-old (mo) mice to evaluate hippocampal memory and the function of both synaptic and non-synaptic mitochondria. Our results indicate that recognition memory is impaired from 12mo, whereas spatial memory is impaired at 18mo. This was accompanied by a differential function of synaptic and non-synaptic mitochondria. Interestingly, we observed premature dysfunction of synaptic mitochondria at 12mo, indicated by increased ROS generation, reduced ATP production and higher sensitivity to calcium overload, an effect that is not observed in non-synaptic mitochondria. In addition, at 18mo both mitochondrial populations showed bioenergetic defects, but synaptic mitochondria were prone to swelling than non-synaptic mitochondria. Finally, we treated 2, 11, and 17mo mice with MitoQ or Curcumin (Cc) for 5 weeks, to determine if the prevention of synaptic mitochondrial dysfunction could attenuate memory loss. Our results indicate that reducing synaptic mitochondrial dysfunction is sufficient to decrease age-associated cognitive impairment. In conclusion, our results indicate that age-related alterations in ATP produced by synaptic mitochondria are correlated with decreases in spatial and object recognition memory and propose that the maintenance of functional synaptic mitochondria is critical to prevent memory loss during aging.

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Hippocampus-dependent learning and memory are impaired with age, which correlated with synaptic mitochondrial dysfunction.

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Synaptic mitochondria fail before non-synaptic mitochondria, indicating premature synaptic mitochondrial damage in aging.

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Reducing synaptic mitochondrial dysfunction, with MitoQ or Curcumin, decrease age-associated hippocampal memory impairment.

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Age-related changes in ATP production of synaptic mitochondria correlated with decreased hippocampal memory.

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Maintenance of functional synaptic mitochondria is critical to prevent memory loss during aging.

The TGF-β profibrotic cascade targets ecto-5'-nucleotidase gene in proximal tubule epithelial cells and is a traceable marker of progressive diabetic kidney disease

Progressive diabetic nephropathy (DN) and loss of renal function correlate with kidney fibrosis. Crosstalk between TGF-β and adenosinergic signaling contributes to the phenotypic transition of cells and to renal fibrosis in DN models. We evaluated the role of TGF-β on NT5E gene expression coding for the ecto-5`-nucleotidase CD73, the limiting enzyme in extracellular adenosine production. We showed that high d-glucose may predispose HK-2 cells towards active transcription of the proximal promoter region of the NT5E gene while additional TGF-β results in full activation. The epigenetic landscape of the NT5E gene promoter was modified by concurrent TGF-β with occupancy by the p300 co-activator and the phosphorylated forms of the Smad2/3 complex and RNA Pol II. Transcriptional induction at NT5E in response to TGF-β was earlier compared to the classic responsiveness genes PAI-1 and Fn1. CD73 levels and AMPase activity were concomitantly increased by TGF-β in HK-2 cells. Interestingly, we found increased CD73 content in urinary extracellular vesicles only in diabetic patients with renal repercussions. Further, CD73-mediated AMPase activity was increased in the urinary sediment of DN patients. We conclude that the NT5E gene is a target of the profibrotic TGF-β cascade and is a traceable marker of progressive DN.

Hormetic-Like Effects of L-Homocysteine on Synaptic Structure, Function, and Aβ Aggregation

Alzheimer’s Disease (AD) is the primary cause of dementia among the elderly population. Elevated plasma levels of homocysteine (HCy), an amino acid derived from methionine metabolism, are considered a risk factor and biomarker of AD and other types of dementia. An increase in HCy is mostly a consequence of high methionine and/or low vitamin B intake in the diet. Here, we studied the effects of physiological and pathophysiological HCy concentrations on oxidative stress, synaptic protein levels, and synaptic activity in mice hippocampal slices. We also studied the in vitro effects of HCy on the aggregation kinetics of Aβ₄₀. We found that physiological cerebrospinal concentrations of HCy (0.5 µM) induce an increase in synaptic proteins, whereas higher doses of HCy (30–100 µM) decrease their levels, thereby increasing oxidative stress and causing excitatory transmission hyperactivity, which are all considered to be neurotoxic effects. We also observed that normal cerebrospinal concentrations of HCy slow the aggregation kinetic of Aβ₄₀, whereas high concentrations accelerate its aggregation. Finally, we studied the effects of HCy and HCy + Aβ₄₂ over long-term potentiation. Altogether, by studying an ample range of effects under different HCy concentrations, we report, for the first time, that HCy can exert beneficial or toxic effects over neurons, evidencing a hormetic-like effect. Therefore, we further encourage the use of HCy as a biomarker and modifiable risk factor with therapeutic use against AD and other types of dementia.

Correction to: Microencapsulation of cellular aggregates composed of differentiated insulin and glucagon-producing cells from human mesenchymal stem cells derived from adipose tissue

[This corrects the article DOI: 10.1186/s13098-020-00573-9.].

Microencapsulation of cellular aggregates composed of differentiated insulin and glucagon-producing cells from human mesenchymal stem cells derived from adipose tissue

BACKGROUND

In type I diabetes mellitus (T1DM) pancreatic β cells are destroyed. Treatment entails exogenous insulin administration and strict diet control, yet optimal glycemic control is hardly attainable. Islet transplant could be an alternative in patients with poor glycemic control, but inefficient islet purification and autoimmune response of patients is still a challenge. For these reasons, it is necessary to explore new cellular sources and immunological isolation methods oriented to develop T1DM cell-based therapies.

AIMS

We postulate human adipose-derived stem cell (hASC) as an adequate source to generate pancreatic islet cells in vitro, and to produce islet-like structures. Furthermore, we propose microencapsulation of these aggregates as an immunological isolation strategy.

METHODS

hASC obtained from lipoaspirated fat tissue from human donors were differentiated in vitro to insulin (Ins) and glucagon (Gcg) producing cells. Then, insulin producing cells (IPC) and glucagon producing cells (GPC) were cocultured in low adhesion conditions to form cellular aggregates, and later encapsulated in a sodium alginate polymer. Expression of pancreatic lineage markers and secretion of insulin or glucagon in vitro were analyzed.

RESULTS

The results show that multipotent hASC efficiently differentiate to IPC and GPC, and express pancreatic markers, including insulin or glucagon hormones which they secrete upon stimulation (fivefold for insulin in IPC, and fourfold for glucagon, compared to undifferentiated cells). In turn, calculation of the Feret diameter and area of cellular aggregates revealed mean diameters of ~ 80 µm, and 65% of the aggregates reached 4000 µm² at 72 h of formation. IPC/GPC aggregates were then microencapsulated in sodium-alginate polymer microgels, which were found to be more stable when stabilized with Ba²⁺, yielding average diameters of ~ 300 µm. Interestingly, Ba²⁺-microencapsulated aggregates respond to high external glucose with insulin secretion.

CONCLUSIONS

The IPC/GPC differentiation process from hASC, followed by the generation of cellular aggregates that are later microencapsulated, could represent a possible treatment for T1DM.

Alcohol impairs hippocampal function: From NMDA receptor synaptic transmission to mitochondrial function

Many studies have reported that alcohol produces harmful effects on several brain structures, including the hippocampus, in both rodents and humans. The hippocampus is one of the most studied areas of the brain due to its function in learning and memory, and a lot of evidence suggests that hippocampal failure is responsible for the cognitive loss present in individuals with recurrent alcohol consumption. Mitochondria are organelles that generate the energy needed for the brain to maintain neuronal communication, and their functional failure is considered a mediator of the synaptic dysfunction induced by alcohol. In this review, we discuss the mechanisms of how alcohol exposure affects neuronal communication through the impairment of glutamate receptor (NMDAR) activity, neuroinflammatory events and oxidative damage observed after alcohol exposure, all processes under the umbrella of mitochondrial function. Finally, we discuss the direct role of mitochondrial dysfunction mediating cognitive and memory decline produced by alcohol exposure and their consequences associated with neurodegeneration.

Situation, challenges, and SEOM recommendations for the future of undergraduate education in Oncology in Spain

PURPOSE

The Spanish Society of Medical Oncology (SEOM, for its Spanish acronym) would like to attest to the relevance of training in Oncology as part of the undergraduate education in Medicine program and issue recommendations to improve said training, with the aim of responding better to the challenges that cancer poses to our society.

MATERIALS AND METHODS

The curricula of 42 schools of medicine were reviewed with interviews with at least one teaching medical oncologist from each faculty. The qualitative and opinion analysis was completed by means of an online questionnaire targeting lecturers, resident tutors, and residents in Medical Oncology (MO), enabling the detection of needs and areas for improvement at an organizational level and in terms of skill acquisition.

RESULTS

While the number of medical schools with a specific, mandatory program in MO has grown by up to 90%, it has not been accompanied by an increase in independent programs. Instead, they largely consist of programs shared with other specialties (61% of the medical faculties). In most of the undergraduate education programs, Oncology contents are fragmented and approached from the perspective of each organ system.

CONCLUSIONS

Despite the positive evolution in recent years, the heterogeneity in Oncology contents during undergraduate education training continues to be remarkable. Cross-sectional programs with an integral vision, taught in the final years of undergraduate medical education would be desirable. Among the recommendations for improvement of training in Medical Oncology, the SEOM proposes that updated, theoretical content be incorporated and clinical practice in Medical Oncology departments be promoted.

112 Comparative study between slow freezing and vitrification on the survival rate of cryopreserved alpaca embryos post-transfer

The objective of this study was to compare the effectiveness of cryopreserving in vivo-produced alpaca embryos by slow freezing v. vitrification. The embryos were produced from 9 female alpacas at Fundo Mallkini, Puno, Peru, located at 4300m elevation. The donor alpacas were synchronized by induction to ovulate with an injection of gonadotropin-releasing hormone (0.0084mg of buserelin acetate) and natural mating with vasectomized males to male receptive donors (day of ovulation induction was considered Day 0). On Day 2, the donors were injected 700IU of eCG. On Day 7, the donors received an injection of prostaglandin F2α (0.25mg of cloprostenol) and were mated on Day 8 by fertile males (2 matings 12h apart: 0600 and 1800h). The embryos were collected at 5.5 days after fertile mating and were graded as per IETS recommendations; most of the embryos were already expanded and hatched blastocysts. Embryos were washed and maintained in holding medium (1L PBS+1g Glucose+36mg sodium pyruvate+0.4% BSA+50mg kanamycin monosulfate) at 23°C for up to 1h and distributed into 2 groups for either slow freezing for direct transfer (n=14 embryos) or vitrification (n=10 embryos). Slow freezing consisted of transfer into freezing medium (9mL of 1.5M ethylene glycol+1mL of 1.0M sucrose prepared in holding media) at 23°C, placing in 0.25-mL straws and subjected to freezing at a rate of −0.5°C/ minute to −35°C and then plunging into LN. Vitrification followed a procedure described for camel embryos whereby embryos were exposed to solutions containing increasing amounts of glycerol and ethylene glycol for fixed periods and were then loaded into an open pull straw and plunged directly into LN for storage. The cryopreserved embryos were transferred into adult alpacas at the Community of Suitucancha, Junin, Peru (1500km from the farm where the embryos were collected and cryopreserved, 4200m elevation). Embryos in the slow-freezing group were thawed in warm water at 37°C for 30s and loaded directly into the embryo transfer gun for direct transfer into 7 alpaca recipients (2 embryos per recipient). Vitrified embryos were warmed by removing the open pull straw from the LN and transferring the embryos to 2 warming solutions at 37°C with decreasing levels of vitricants and containing 0.5M galactose with a final incubation at room temperature in holding media and then transferred into 5 alpaca recipients (2 embryos per recipient). The embryos were transferred into synchronized recipients by transcervical nonsurgical method. Pregnancy diagnosis was made by transrectal ultrasound examination at 45 days post-transfer. The pregnancy rates in the slow-freezing and vitrification groups, respectively, were 2/7 (29%) and 0/5 (0%); the difference was not significant (P&gt;0.05) based on Fisher’s exact test. Twin pregnancies were not detected. We consider the result with slow freezing very promising, as in previous trials we had less than 18% pregnancies. More trials with larger number of embryos per cryopreservation method are being programmed.

Genetic ablation of tau improves mitochondrial function and cognitive abilities in the hippocampus

Tau is a key protein for microtubule stability; however, post-translationally modified tau contributes to neurodegenerative diseases by forming tau aggregates in the neurons. Previous reports from our group and others have shown that pathological forms of tau are toxic and impair mitochondrial function, whereas tau deletion is neuroprotective. However, the effects of tau ablation on brain structure and function in young mice have not been fully elucidated. Therefore, the aim of this study was to investigate the implications of tau ablation on the mitochondrial function and cognitive abilities of a litter of young mice (3 months old). Our results showed that tau deletion had positive effects on hippocampal cells by decreasing oxidative damage, favoring a mitochondrial pro-fusion state, and inhibiting mitochondrial permeability transition pore (mPTP) formation by reducing cyclophilin D (Cyp-D) protein. More importantly, tau deletion increased ATP production and improved the recognition memory and attentive capacity of juvenile mice. Therefore, the absence of tau enhanced brain function by improving mitochondrial health, which supplied more energy to the synapses. Thus, our work opens the possibility that preventing negative tau modifications could enhance brain function through the improvement of mitochondrial health.

Contribution of Tau Pathology to Mitochondrial Impairment in Neurodegeneration

Tau is an essential protein that physiologically promotes the assembly and stabilization of microtubules, and participates in neuronal development, axonal transport, and neuronal polarity. However, in a number of neurodegenerative diseases, including Alzheimer’s disease (AD), tau undergoes pathological modifications in which soluble tau assembles into insoluble filaments, leading to synaptic failure and neurodegeneration. Mitochondria are responsible for energy supply, detoxification, and communication in brain cells, and important evidence suggests that mitochondrial failure could have a pivotal role in the pathogenesis of AD. In this context, our group and others investigated the negative effects of tau pathology on specific neuronal functions. In particular, we observed that the presence of these tau forms could affect mitochondrial function at three different levels: (i) mitochondrial transport, (ii) morphology, and (iii) bioenergetics. Therefore, mitochondrial dysfunction mediated by anomalous tau modifications represents a novel mechanism by which these forms contribute to the pathogenesis of AD. In this review, we will discuss the main results reported on pathological tau modifications and their effects on mitochondrial function and their importance for the synaptic communication and neurodegeneration.

Deficient mitochondrial biogenesis in IL-2 activated NK cells correlates with impaired PGC1-α upregulation in elderly humans

Immunosenescence has been described as age-associated changes in the immune function which are thought to be responsible for the increased morbidity with age. Human Natural Killer (NK) cells are a specialized heterogeneous subpopulation of lymphocytes involved in immune defense against tumor and microbial diseases. Interestingly, aging-related NK cell dysfunction is associated with features of aging such as tumor incidence, reduced vaccination efficacy, and short survival due to infection. It is known that NK cell effector functions are critically dependent on cytokines and metabolic activity. Our aim was to determine whether there is a difference in purified human NK cell function in response to high concentration of IL-2 between young and elder donors. Here, we report that the stimulation of human NK cells with IL-2 (2000 U/mL) enhance NK cell cytotoxic activity from both young and elderly donors. However, while NK cells from young people responded to IL-2 signaling by increasing mitochondrial mass and mitochondrial membrane potential, no increase in these mitochondrial functional parameters was seen in purified NK cells from elderly subjects. Moreover, as purified NK cells from the young exhibited an almost three-fold increase in PGC-1α expression after IL-2 (2000 U/mL) stimulation, PGC-1α expression was inhibited in purified NK cells from elders. Furthermore, this response upon PGC-1α expression after IL-2 stimulation promoted an increase in ROS production in NK cells from elderly humans, while no increase in ROS production was observed in NK cells of young donors. Our data show that IL-2 stimulates NK cell effector function through a signaling pathway which involves a PGC-1α-dependent mitochondrial function in young NK cells, however it seems that NK cells from older donors exhibit an altered IL-2 signaling which affects mitochondrial function associated with an increased production of ROS which could represent a feature of NK cell senescence.

Abstract P3-09-08: Overeating and breast cancer risk by pathologic subtypes: EpiGEICAM study

Introduction: It has been reported that overeating may be the greatest avoidable cause of cancer in nonsmokers and obesity increases postmenopausal breast cancer (BC) risk. Calorie restriction reduces BC incidence in experimental animals, but the evidence in humans is more limited. This study analyzes the association between female BC risk and excessive or restricted calorie consumption in Spain.

Methods: EpiGEICAM is a multicenter case-control study including 1017 matched pairs (age & town) of incident BC cases and healthy controls in 14 regions in Spain. Participants filled a structured questionnaire. Average calorie intake (cals) during the 5 years previous to diagnosis (cases) or interview (controls) was estimated using a validated 117-item semiquantitative food-frequency questionnaire. Expected calorie intake (cals_exp) was calculated from a linear regression model taking into account the basal metabolic rate (Sabounchi's meta-regression) and the amount of physical activity performed by each woman (5 categories). For each woman the prediction interval (99%) of cals_exp was used to consider her calorie intake as “normal” (NCI) (cals inside this interval –the reference group-), “excesive” (ECI) (cals&gt;upper limit of the interval) or “restricted” (RCI) (cals&lt;lower limit of the interval). The association of ECI and RCI with BC, overall and by pathologic subtype (luminal (ER+ and/or PR+ with HER2-), HER2+ and triple negative), was evaluated using conditional and multinomial logistic regression models, adjusted for age and region (multinomial models), education, body mass index (BMI), smoking, age at menarche & at first birth, menopausal status, previous history of benign breast disease, family history of BC, hormonal replacement therapy (HRT), physical activity and two scores reflecting the participant's adherence to Mediterranean and Western dietary patterns.

Results: After excluding participants with extreme calorie intake, 973 case-control pairs were considered. Average number of calories was higher in BC cases (1990 kcals) than controls (1897 kcals) P=0.001). Women with RCI (cals&lt;80% of the predicted limit) had lower BC risk (OR=0.52, P=0.001), being this effect more marked in premenopausal women (OR=0.36; Pheterogeneity=0.001). On the contrary, women with ECI (cals&gt;40% of the predicted limit) showed increased BC risk (OR=1.92; P=0.001), being this effect stronger in postmenopausal women (OR=2.81; Pheterogenity=0.001). By pathologic subtypes, no statistically significant differences were observed, but ECI (over 40%) was strongly associated with HER2+ tumors (OR=2.05, P=0.021). No differences in the effect of ECI or RCI were observed by levels of BMI, tobacco or HRT.

Conclusion: After taking BMI into account, excessive energy intake increases BC risk, while relative caloric restriction seems to have a protective effect. Moderate calorie restriction, in combination with regular physical activity, could be a good strategy for BC prevention.

Funding:Scientific Foundation of the Spanish Association Against Cancer (AECC), SEOM, FECMA, Cerveza y Salud Foundation, FIS CD110/00018

Citation Format: Pollán M, Castelló A, Martín M, Ruiz A, Casas AM, Baena JM, Antolin S, Ramos M, Garcia-Saénz JA, Muñoz M, Lluch A, de Juan A, Jara C, Sánchez Rovira P, Antón A, Chacón JI, Arcusa A, Jimeno MA, Bezares S, Carrasco E, Pérez-Gómez B, Lope V. Overeating and breast cancer risk by pathologic subtypes: EpiGEICAM study [abstract]. In: Proceedings of the 2017 San Antonio Breast Cancer Symposium; 2017 Dec 5-9; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2018;78(4 Suppl):Abstract nr P3-09-08.

The Identification of Congeners and Aliens by Drosophila Larvae

We investigated the role of Drosophila larva olfactory system in identification of congeners and aliens. We discuss the importance of these activities in larva navigation across substrates, and the implications for allocation of space and food among species of similar ecologies. Wild type larvae of cosmopolitan D. melanogaster and endemic D. pavani, which cohabit the same breeding sites, used species-specific volatiles to identify conspecifics and aliens moving toward larvae of their species. D. gaucha larvae, a sibling species of D. pavani that is ecologically isolated from D. melanogaster, did not respond to melanogaster odor cues. Similar to D. pavani larvae, the navigation of pavani female x gaucha male hybrids was influenced by conspecific and alien odors, whereas gaucha female x pavani male hybrid larvae exhibited behavior similar to the D. gaucha parent. The two sibling species exhibited substantial evolutionary divergence in processing the odor inputs necessary to identify conspecifics. Orco (Or83b) mutant larvae of D. melanogaster, which exhibit a loss of sense of smell, did not distinguish conspecific from alien larvae, instead moving across the substrate. Syn97CS and rut larvae of D. melanogaster, which are unable to learn but can smell, moved across the substrate as well. The Orco (Or83b), Syn97CS and rut loci are necessary to orient navigation by D. melanogaster larvae. Individuals of the Trana strain of D. melanogaster did not respond to conspecific and alien larval volatiles and therefore navigated randomly across the substrate. By contrast, larvae of the Til-Til strain used larval volatiles to orient their movement. Natural populations of D. melanogaster may exhibit differences in identification of conspecific and alien larvae. Larval locomotion was not affected by the volatiles.

Preventive treatments for breast cancer: recent developments

Breast cancer is a burden for western societies, and an increasing one in emerging economies, because of its high incidence and enormous psychological, social, sanitary and economic costs. However, breast cancer is a preventable disease in a significant proportion. Recent developments in the armamentarium of effective drugs for breast cancer prevention (namely exemestane and anastrozole), the new recommendation from the National Institute for Health and Care Excellence to use preventative drugs in women at high risk as well as updated Guidelines from the US Preventive Services Task Force and the American Society of Clinical Oncology should give renewed momentum to the pharmacological prevention of breast cancer. In this article we review recent major developments in the field and examine their ongoing repercussion for breast cancer prevention. As a practical example, the potential impact of preventive measures in Spain is evaluated and a course of practical actions is delineated.

Blood volumes in cardiac surgery with cardiopulmonary bypass

PURPOSE

Total blood volume (TBV) estimation potentially impacts various aspects of cardiac surgical care, including pharmacological and transfusion interventions, hemodynamic and volume management and perfusion equipment selection. TBV is commonly computed during cardiopulmonary bypass (CPB), using standardized formulae. We hypothesized that these equations fail to accurately predict individual blood volume variability. The aim of this study was to determine TBV with a dilution technique and compare the results to commonly utilized TBV calculations.

METHODS

After institutional review board approval, data was prospectively collected and analyzed for 101 patients undergoing open-heart surgery. Hematocrits (Hct) just prior to and immediately after the initiation of CPB were used to calculate the TBV. Results were compared to (1) the Allen formula and (2) weight-based standards (70 ml/kg for males (SM); 65 ml/kg for females (SF)).

RESULTS

The average dilution TBV (male: 4684 ± 1641 ml; female: 3027 ± 1067 ml; total: 4175 ± 1617 ml) was significantly smaller (p<0.05) than TBV estimated by Allen's formula (male: 6328 ± 973 ml; female: 4167 ± 643 ml; total: 5665 ± 1134 ml) and weight-based standards (male: 6278 ± 1256 ml; female: 4924 ± 1064 ml; total: 5862 ± 1350 ml). Allen's formula and the weight-based standards correlated strongly (R(2) = 0.821, p<0.001), suggesting similar estimates of TBV when using these methods. In contrast, hemodilution correlated poorly with the estimates by Allen (R(2) = 0.221, p<0.001) and weight-based formulae (R(2) = 0.122, p<0.001), suggesting different TBV computation.

CONCLUSIONS

The dilution method during CPB for TBV estimation is applicable and reproducible in the cardiac surgical arena and can be utilized to calculate TBV. Our results suggest that traditional TBV assessment in cardiac surgical patients by Allen's and weight-based formulae lacks the desired accuracy in estimating true TBV.

Blood volume measurement by hemodilution: association with valve disease and re-evaluation of the Allen Formula

BACKGROUND

Total blood volume (TBV) assessment is central to the management of cardiac surgical patients with cardiopulmonary bypass (CPB). The widely accepted Allen Formula lacks accuracy in estimating TBV in these patients. Moreover, the impact of commonly encountered cardiac disease states on TBV has not been systematically investigated. The aim of this study was to determine TBV by hemodilution (TBVHD) for patients with valve disease, compare TBVHD to algorithms frequently used during cardiac surgery and to modify the Allen Formula to better fit today's patient population.

METHODS

TBVHD was prospectively measured upon initiation of CPB. Ninety-six patients were grouped into 4 cohorts by preoperative diagnosis and compared to Allen and weight-based formulae in a univariate analysis: mitral regurgitation (MR), coronary artery disease requiring bypass surgery (CABG) and aortic stenosis (AS) ± CABG. The independent effects of height and weight on TBV were correlated to the original Allen Formula by multiple linear regression.

RESULTS

Patients with MR had significantly larger TBVHD compared to patients with AS, CABG or both. The smallest TBVHD was found in the patients with AS and CABG. The modified Allen Formula had an excellent model fit (R(2) = 0.88 and R(2) = 0.95 for males and females, respectively; p<0.001) while the classic formula overestimated TBV by 30% in males and females. For males, height impacted TBV calculations the most whereas weight was the predominant determinant in females.

CONCLUSION

Blood volume assessment via the Allen Formula or bodyweight overestimated TBV in cardiac surgical patients, with potential implications on their management. The assumption that MR frequently presents with increased intravascular volume was confirmed whereas AS patients with coronary disease had a relatively smaller TBV. Lastly, a modified Allen Formula to better reflect today's patient population was derived to reproducibly improve accuracy in mathematical estimates of TBV.

Final results of a phase II study of paclitaxel, bevacizumab, and gemcitabine as first-line therapy for patients with HER2-negative metastatic breast cancer

BACKGROUND

Efficacy and safety data for combining bevacizumab, gemcitabine, and paclitaxel for locally advanced/metastatic breast cancer are limited.

PATIENTS AND METHODS

AVALUZ trial evaluates the combination of bevacizumab 10 mg/kg, gemcitabine 2,000 mg/m(2) plus paclitaxel 150 mg/m(2), on days 1 and 15 of each 28-day course in previously untreated HER-2 negative patients.

RESULTS

Median progression-free survival (PES): 12.3 months. The overall response and clinical benefit rate (CR + PR + SD) were 72 % (95 % CI 60.9-82.0 %) and 89 % (95 % CI 80.3-95.3 %), respectively. Median overall survival: 27.4 mo. Baseline circulating tumor cell (CTCs) ≥2 versus CTCs <2 was associated with lower PFS, p = 0.046. Overall response was significantly greater in patients with intense angiotensin type 1 receptor (AGTR1) expression (99 vs. 60 % [p = 0.021]). The most frequent grade 3/4 adverse events were: neutropenia (10 %); febrile neutropenia (1 %); sensory neuropathy (13 %); and asthenia (6 %). Grade 3 adverse events of interest with bevacizumab included bleeding (1 %) and hypertension (4 %). One patient developed cardiac ischemia (1 %).

CONCLUSIONS

Adding bevacizumab to chemotherapy appeared feasible and well tolerated, producing toxicity comparable to other effective combined first-line regimens. Baseline circulating endothelial cells and AGTR1 expression are predictive of PFS and response.

Oxidative stress in the mollusk Echinolittorina peruviana (Gasteropoda: Littorinidae, Lamarck, 1822) and trace metals in coastal sectors with mining activity

The aim of the study was to evaluate the effect of coastal waters of sites with mining activity in Echinolittorina peruviana, through oxidative stress biomarkers and heavy metals determination both in water and in tissue. Organisms were collected in the intertidal zone in areas with and without mining activity. Metal concentrations in the water and tissues, and also, the following biomarkers of oxidative stress: antioxidant enzyme activity, superoxide dismutase and catalase, non-enzymatic oxidative capacity (TRAP), oxidative damage to proteins (carbonyls) and TBARS, were measured The concentrations of accumulated metals had the following order Fe > Cu > Cd > Zn > Cr > Mo > As; the highest concentrations of metals in water and tissues were found in Caleta Palito and Chañaral. Results suggest that the coastal waters with mining activity and greatest concentrations of copper and iron induced the greater antioxidant response and oxidative damage to lipids in E. peruviana.

The neuro-ecology of Drosophila pupation behavior

Many species of Drosophila form conspecific pupa aggregations across the breeding sites. These aggregations could result from species-specific larval odor recognition. To test this hypothesis we used larval odors of D. melanogaster and D. pavani, two species that coexist in the nature. When stimulated by those odors, wild type and vestigial (vg) third-instar larvae of D. melanogaster pupated on conspecific larval odors, but individuals deficient in the expression of the odor co-receptor Orco randomly pupated across the substrate, indicating that in this species, olfaction plays a role in pupation site selection. Larvae are unable to learn but can smell, the Syn^97CS and rut strains of D. melanogaster, did not respond to conspecific odors or D. pavani larval cues, and they randomly pupated across the substrate, suggesting that larval odor-based learning could influence the pupation site selection. Thus, Orco, Syn^97CS and rut loci participated in the pupation site selection. When stimulated by conspecific and D. melanogaster larval cues, D. pavani larvae also pupated on conspecific odors. The larvae of D. gaucha, a sibling species of D. pavani, did not respond to D. melanogaster larval cues, pupating randomly across the substrate. In nature, D. gaucha is isolated from D. melanogaster. Interspecific hybrids, which result from crossing pavani female with gaucha males clumped their pupae similarly to D. pavani, but the behavior of gaucha female x pavani male hybrids was similar to D. gaucha parent. The two sibling species show substantial evolutionary divergence in organization and functioning of larval nervous system. D. melanogaster and D. pavani larvae extracted information about odor identities and the spatial location of congener and alien larvae to select pupation sites. We hypothesize that larval recognition contributes to the cohabitation of species with similar ecologies, thus aiding the organization and persistence of Drosophila species guilds in the wild.

Abstract P3-15-02: A prospective, open label, non-comparative trial to determine the incidence of chemotherapy-induced nausea and vomiting associated with the docetaxel-cyclophosphamide regimen in early breast cancer patients. Results from the GEICAM 2009-02 study

Background: Docetaxel-Cyclophosphamide (TC) has become a common chemotherapy regimen for moderate-high risk Early Breast Cancer (EBC) patients. The incidence of chemotherapy induced nausea and vomiting (CINV) with TC together with an adequate standard anti-emetic therapy with 5-HT3 antagonist and corticosteroids are unknown. This study investigates the incidence of emesis control (complete response), defined as no vomiting (any grade of NCI CTCAE version 4.0) and no use of rescue treatment within 120 hours after the first cycle of TC. Secondary objective evaluates the efficacy of Aprepitant in non-responding patients.

Methods: EBC patients with no prior moderate-high risk CINV were included. Patients received Docetaxel 75 mg/m2 plus Cyclophosphamide 600 mg/m2 IV every three weeks. Antiemetic treatment consisted of oral Dexamethasone (D) 8 mg (at night) on day 0; oral D 8 mg x 3 (in the morning, 1 hour before chemotherapy and at night) plus 5-HT3 antagonists on day 1; and oral D 8 mg x 2 (in the morning and at night) on days 2 and 3. Non-responding patients (vomiting or need of rescue therapy in the first cycle) were offered participation in the efficacy phase (Aprepitant 125mg day 1 and 80 mg days 2 and 3 added to the standard antiemetic therapy in cycle 2). In addition to the standard NCI-CTCAE adverse event collection, a patient´s diary (from day 1 to 6) and the FLIE (Functional Living Index-Emesis questionnaire) were used. Assuming a 25% (+/- 6%) of patients resistant to standard antiemetic therapy, 212 patients were estimated.

Results: From May-11 to March-13, 212 EBC patients were included. Median age was 57 years (range 34-82), 29.3% were premenopausal. Twenty-seven patients were excluded from the main analysis because of major protocol violations (25) or consent withdrawal (2). Twenty-four patients (13%; IC95%: 8.2 – 17.8) did not respond to standard antiemetics and entered the efficacy phase with Aprepitant. From these 24 patients, 14 (56%; IC95%: 36.5 – 75.5) achieved a complete response on cycle 2. No adverse events related to Aprepitant were observed.

Conclusions: Proper use of standard antiemetic therapy for early breast cancer patients treated with TC provides a high control rate (87%). Among no responding patients, about half of them were rescued with Aprepitant. Identification of the non-responding patients could lead to a better antiemetic control with Aprepitant from the first cycle.

Citation Information: Cancer Res 2013;73(24 Suppl): Abstract nr P3-15-02.

Pain in clinical oncology: patient satisfaction with management of cancer pain

BACKGROUND

Despite effective analgesic therapy, inadequate pain control is frequently perceived by patients and caregivers.

AIMS

To assess satisfaction with management of pain in cancer patients.

METHODS

Between January and May 2007, a cross-sectional multicentre study was conducted in 64 Medical Oncology Departments throughout Spain. A total of 525 outpatients with oncological diseases completed a questionnaire with demographic data, characteristics and intensity of pain, and perceptions and attitudes towards pain management at the time of a routine clinical visit. Physicians also completed a questionnaire with tumour-related and treatment-related data. Cluster analysis was used to classify patients into three groups (satisfied, neither satisfied nor dissatisfied or neutral, dissatisfied) according to pain intensity and satisfaction with treatment.

RESULTS

Patients satisfied with their analgesic treatment (33%) had lower pain intensities and, when regularly asked about their pain, considered their physicians to be more involved in their treatment. Neither satisfied nor dissatisfied patients (neutral) (44%) had higher mean pain intensities. Two-thirds of them achieved marked relief of their pain and also thought that physicians were aware of their situation. Dissatisfied patients (23%) had moderate to severe pain intensities, and said that they were asked less frequently about their pain, and thought that their physicians were less involved in their analgesic treatment.

CONCLUSION

Physician-patient communication and information provided to patients are essential aspects of patient perceptions and attitudes towards control of cancer-related pain. Pain is seen as a condition that may be controlled but affects the capacity to lead a normal life.

P1-14-03: AVALUZ Study: First Line with Bevacizumab in Combination with Paclitaxel (P) and Gemcitabine (G) in Patients with HER-2 Negative Recurrent or Metastatic BC: PFS Analysis

Background The combination of bevacizumab (B) with taxanes, capecitabine or anthracyclines has shown increased PFS in pts with mBC. The combination with G and P has been evaluated and has demonstrated high response rate and good toxicity profile. The aim of this study is to evaluate the efficacy and toxicity profile of the combination of B with G and P, providing an update of PFS and the toxicity experienced in all patients treated.

Methods A phase II multicenter, national, open-label study in pts diagnosed of recurrent or metastatic HER-2 negative BC, treated with first line B 10 mg/kg, P 150 mg/m2 and G 2000 mg/m2 day 1 and 15 c/28 d until progression disease, unacceptable toxicity or medical decision. This abstract evaluates efficacy by PFS as primary endpoint and as secondary endpoints: response rate and toxicity profile (NCI CTC v3.0 criteria).

Results From January 2009 to December 2009, 82 evaluable patients were recruited in 23 sites. The characteristic of the all of patients included (90) are: median age 51.5 (26-81), ER + 68%, PR + 59%, triple negative pts 19%, previous chemotherapy (neoadj or adj) 64.4% and ≥ 3 metastatic sites 21% of patients (19). The median cycles administered per pts was 7 (1-26) and the relative median dose intensity was 0.93 for B, 0.89 for P and 0.91 for G.

Of the 75 patients with response assessment, the overall response rate obtained was 72% with a clinical benefit of 89.3% (80.6−95.28%) (CR 14.7% (11), PR 57.3% (43), SD 17.3% and PD 10.7%). Of the 82 patients with a median follow up of 16.5 m (0.16- 26.38), preliminary median PFS (43% events) for these pts was 11.48 m (8.98−15.72), the median duration of first response (MDR) was 12.4 m (7.47-NA) and the median OS was 21.35 m (20.72- NA). The one year OS% was 84.15% (74.27 - 90.47).

Toxicity was generally manageable. Related AEs have been reported in 67/82 patients which were mostly mild or moderate. Safety analysis revealed 24 SAEs in 21 patients.

Conclusions Bevacizumab in combination with paclitaxel and gemcitabine showed significant PFS compared with the published data with paclitaxel and gemcitabine and high clinical benefit with manageable safety profile.

Citation Information: Cancer Res 2011;71(24 Suppl):Abstract nr P1-14-03.

Abstract P2-16-13: Phase II Open Label Trial Bevacizumab in Combination with Paclitaxel and Gemcitabine as First Line in Patients with HER-2 Negative Recurrent or Metastatic Breast Cancer (AVALUZ): First Analysis

Background:

The combination of bevacizumab with taxanes, capecitabine or anthracyclines has shown increased progression-free survival in patients with metastatic breast carcinoma. The aim of this study is to evaluate the efficacy and toxicity profile of the combination of bevacizumab with gemcitabine and paclitaxel, providing a preliminary analysis of response in patients included for whom at least one response assessment and the toxicity experienced in all patients treated.

Methods:

A Phase II multicenter, national, open-label study in patients diagnosed of recurrent or metastatic HER-2 negative breast carcinoma, treated with first-line bevacizumab 10 mg/kg, paclitaxel 150 mg/m2 and gemcitabine 2000 mg/m2 day 1 and 15 c/28d until disease progression, unacceptable toxicity, or medical decision. This abstract evaluates efficacy by the response rate and the toxicity profile of the combination in all cycles of all patients included. The primary end-point of the study is PFS. Toxicity is evaluated according to NCI CTC v 3.0 criteria. Results:

From January 2009 to December 2009, 82 evaluable patients were recruited in 23 sites, with at least one response assessment available in 69. Median age 51.5 (26-81), ER+ 59 pts, PR+ 51 pts, triple negative patients 16 and previous chemotherapy (neoadj or adj) 58 pts. Of the 69 pts with response assessment, the last assessment is in cycle 3 for 31.88% of patients, cycle 6: 33.33%, cycle 9: 4.35%, cycle 12: 1.45% and at the end of treatment 29%. The median cycles administered per patient is 6 (1-14) and the relative median dose intensity is 0.93 for bevacizumab, 0.91 for paclitaxel, and 0.93 for gemcitabine.

The overall response obtained was 69.57%, with a clinical benefit of 89.86% (CR 8.7% (6), PR 60.87% (42), SD 20.29%, and DP 10.14%). Of the 82 patients with a median follow-up of 7.19 m (0.16-13.98), grade 3-4 toxicity affected 41%, with treatment discontinuation for adverse events in 19.51%. Eighteen SAEs were reported: pyrexia (4), infection at catheter site (2), urine infection and a single case of angor, hypertension, pulmonary embolism, pleural effusion, febrile neutropenia, neutropenia, vomiting, diarrhoea, dehydration, atrial fibrillation, and dizziness. Toxicity was generally easily controlled. Conclusions:

Although data from the primary study endpoint (PFS) are not yet available, the treatment regimen obtained a high overall response in patients treated and was well tolerated by this patient group.

Citation Information: Cancer Res 2010;70(24 Suppl):Abstract nr P2-16-13.

Polymorphisms in cytochromes P450 2C8 and 3A5 are associated with paclitaxel neurotoxicity

Neurotoxicity is one of the most relevant dose-limiting toxicities of the anticancer drug paclitaxel. It exhibits substantial interindividual variability of unknown molecular basis, and represents one of the major challenges for the improvement of paclitaxel therapy. The extensive variability in paclitaxel clearance and metabolism lead us to investigate the association between polymorphisms in paclitaxel elimination pathway and neurotoxicity. We selected 13 relevant polymorphisms in genes encoding paclitaxel metabolizing enzymes (CYP2C8, CYP3A4 and CYP3A5) and transporters (organic anion transporting polypeptide (OATP) 1B1, OATP1B3 and P-glycoprotein) and genotyped them in 118 Spanish cancer patients treated with paclitaxel. After adjusting for age and treatment schedule, CYP2C8 Haplotype C and CYP3A5*3 were associated with protection (hazard ratio (HR) (per allele)=0.55; 95% confidence interval (CI)=0.34-0.89; P=0.014 and HR (per allele)=0.51; 95%CI=0.30-0.86; and P=0.012, respectively) and CYP2C8*3 with increased risk (HR (per allele)=1.72; 95%CI=1.05-2.82; and P=0.032). In each case, the allele causing increased paclitaxel metabolism was associated with increased neurotoxicity, suggesting an important role for metabolism and hydroxylated paclitaxel metabolites. We estimated the HR per paclitaxel-metabolism increasing allele carried across the three polymorphisms to be HR=1.64 (95% CI=1.26-2.14; P=0.0003). The results for P-glycoprotein were inconclusive, and no associations were observed for the other genes studied. The incorporation of this genetic data in treatment selection could help to reduce neurotoxicity events, thereby individualizing paclitaxel pharmacotherapy. These results warrant validation in independent series.