Mitochondrial metabolism sustains CD8+ T cell migration for an efficient infiltration into solid tumors

The ability of CD8+ T cells to infiltrate solid tumors and reach cancer cells is associated with improved patient survival and responses to immunotherapy. Thus, identifying the factors controlling T cell migration in tumors is critical, so that strategies to intervene on these targets can be developed. Although interstitial motility is a highly energy-demanding process, the metabolic requirements of CD8+ T cells migrating in a 3D environment remain unclear. Here, we demonstrate that the tricarboxylic acid (TCA) cycle is the main metabolic pathway sustaining human CD8+ T cell motility in 3D collagen gels and tumor slices while glycolysis plays a more minor role. Using pharmacological and genetic approaches, we report that CD8+ T cell migration depends on the mitochondrial oxidation of glucose and glutamine, but not fatty acids, and both ATP and ROS produced by mitochondria are required for T cells to migrate. Pharmacological interventions to increase mitochondrial activity improve CD8+ T cell intratumoral migration and CAR T cell recruitment into tumor islets leading to better control of tumor growth in human xenograft models. Our study highlights the rationale of targeting mitochondrial metabolism to enhance the migration and antitumor efficacy of CAR T cells in treating solid tumors.

The dual role of citrate in cancer

Citrate is a key metabolite of the Krebs cycle that can also be exported in the cytosol, where it performs several functions. In normal cells, citrate sustains protein acetylation, lipid synthesis, gluconeogenesis, insulin secretion, bone tissues formation, spermatozoid mobility, and immune response. Dysregulation of citrate metabolism is implicated in several pathologies, including cancer. Here we discuss how cancer cells use citrate to sustain their proliferation, survival, and metastatic progression. Also, we propose two paradoxically opposite strategies to reduce tumour growth by targeting citrate metabolism in preclinical models. In the first strategy, we propose to administer in the tumor microenvironment a high amount of citrate, which can then act as a glycolysis inhibitor and apoptosis inducer, whereas the other strategy targets citrate transporters to starve cancer cells from citrate. These strategies, effective in several preclinical in vitro and in vivo cancer models, could be exploited in clinics, particularly to increase sensibility to current anti-cancer agents.

The potential for citrate to reinforce epigenetic therapy by promoting apoptosis

Epigenetic drugs induce ATP depletion, promoting a glycolysis-to-oxidative phosphorylation (OXPHOS) shift which sometimes favors tumor growth by promoting necroptosis over apoptosis. To restore effective apoptosis in tumors, we propose that the administration of citrate could inhibit ATP production, activate caspase-8 (a key necroptosis inhibitor), and downregulate key anti-apoptotic proteins (Bcl-xL and MCL1).

The strategic roles of four enzymes in the interconnection between metabolism and oncogene activation in non-small cell lung cancer: Therapeutic implications

NSCLC is the leading cause of cancer mortality and represents a major challenge in cancer therapy. Intrinsic and acquired anticancer drug resistance are promoted by hypoxia and HIF-1α. Moreover, chemoresistance is sustained by the activation of key signaling pathways (such as RAS and its well-known downstream targets PI3K/AKT and MAPK) and several mutated oncogenes (including KRAS and EGFR among others). In this review, we highlight how these oncogenic factors are interconnected with cell metabolism (aerobic glycolysis, glutaminolysis and lipid synthesis). Also, we stress the key role of four metabolic enzymes (PFK1, dimeric-PKM2, GLS1 and ACLY), which promote the activation of these oncogenic pathways in a positive feedback loop. These four tenors orchestrating the coordination of metabolism and oncogenic pathways could be key druggable targets for specific inhibition. Since PFK1 appears as the first tenor of this orchestra, its inhibition (and/or that of its main activator PFK2/PFKFB3) could be an efficacious strategy against NSCLC. Citrate is a potent physiologic inhibitor of both PFK1 and PFKFB3, and NSCLC cells seem to maintain a low citrate level to sustain aerobic glycolysis and the PFK1/PI3K/EGFR axis. Awaiting the development of specific non-toxic inhibitors of PFK1 and PFK2/PFKFB3, we propose to test strategies increasing citrate levels in NSCLC tumors to disrupt this interconnection. This could be attempted by evaluating inhibitors of the citrate-consuming enzyme ACLY and/or by direct administration of citrate at high doses. In preclinical models, this "citrate strategy" efficiently inhibits PFK1/PFK2, HIF-1α, and IGFR/PI3K/AKT axes. It also blocks tumor growth in RAS-driven lung cancer models, reversing dedifferentiation, promoting T lymphocytes tumor infiltration, and increasing sensitivity to cytotoxic drugs.

Metabolic oscillations during cell-cycle progression

We discuss how metabolism changes during different phases of the cell cycle to sustain biosynthesis and replication in normal and cancer cells. We also highlight how several master regulators of cell cycle, such as cyclin-cyclin-dependent kinases (cyc-CDK complexes) and E3 proteasome ligases, modulate key metabolic enzymes to support cell-cycle progression.

How Phosphofructokinase-1 Promotes PI3K and YAP/TAZ in Cancer: Therapeutic Perspectives

Simple Summary

We propose that PFK1 promotes a positive feedback loop with PI3K/AKT and YAP/TAZ signaling pathways in cancer cells. Therefore, targeting PFK1 (or its product F-1,6-BP) could improve the efficacy of PI3K and YAP/TAZ inhibitors currently tested in clinical trials. To this aim, we suggest the use of citrate, which is a physiologic and potent inhibitor of PFK1.

Abstract

PI3K/AKT is one of the most frequently altered signaling pathways in human cancers, supporting the activation of many proteins sustaining cell metabolism, proliferation, and aggressiveness. Another important pathway frequently altered in cancer cells is the one regulating the YAP/TAZ transcriptional coactivators, which promote the expression of genes sustaining aerobic glycolysis (such as WNT, MYC, HIF-1), EMT, and drug resistance. Of note, the PI3K/AKT pathway can also regulate the YAP/TAZ one. Unfortunately, although PI3K and YAP inhibitors are currently tested in highly resistant cancers (both solid and hematologic ones), several resistance mechanisms may arise. Resistance mechanisms to PI3K inhibitors may involve the stimulation of alternative pathways (such as RAS, HER, IGFR/AKT), the inactivation of PTEN (the physiologic inhibitor of PI3K), and the expression of anti-apoptotic Bcl-xL and MCL1 proteins. Therefore, it is important to improve current therapeutic strategies to overcome these limitations. Here, we want to highlight how the glycolytic enzyme PFK1 (and its product F-1,6-BP) promotes the activation of both PI3K/AKT and YAP/TAZ pathways by several direct and indirect mechanisms. In turn, PI3K/AKT and YAP/TAZ can promote PFK1 activity and F-1,6-BP production in a positive feedback loop, thus sustaining the Warburg effect and drug resistance. Thus, we propose that the inhibition of PFK1 (and of its key activator PFK2/PFKFB3) could potentiate the sensitivity to PI3K and YAP inhibitors currently tested. Awaiting the development of non-toxic inhibitors of these enzymes, we propose to test the administration of citrate at a high dosage, because citrate is a physiologic inhibitor of both PFK1 and PFK2/PFKFB3. Consistently, in various cultured cancer cells (including melanoma, sarcoma, hematologic, and epithelial cancer cells), this “citrate strategy” efficiently inhibits the IGFR1/AKT pathway, promotes PTEN activity, reduces Bcl-xL and MCL1 expression, and increases sensitivity to standard chemotherapy. It also inhibits the development of sarcoma, pancreatic, mammary HER⁺ and lung RAS-driven tumors in mice without apparent toxicities.

On the footsteps of Hippocrates, Sanctorius and Harvey to better understand the influence of cold on the occurrence of COVID-19 in European countries in 2020

COVID-19 pandemic has been characterized by a pattern of consecutive declines and regrowth in European countries in 2020. After being partially regressed during the summer, the reappearance of the infection during fall 2020 in many temperate countries strongly suggests that temperature and cold may play a role in influencing the infectivity and virulence of SARS-CoV-2. While promoting medicine as an art, Hippocrates interpreted with logical reasoning the occurrence of diseases such as epidemics, as a consequence of environmental factors, in particular climatic variations. During the Renaissance, Sanctorius was one of the first to perform quantitative measurements, and Harvey discovered the circulation of blood by performing experimental procedures in animals. We think that a reasoning mixing various observations, measurements and experiments is fundamental to understand how cold increases infectivity and virulence of SARS-CoV-2. By this review, we provide evidence linking cold, angiotensin-II, vasoconstriction, hypoxia and aerobic glycolysis (the Warburg effect) to explain how cold affects the epidemiology of COVID-19. Also, a low humidity increases virus transmissibility, while a warm atmosphere, a moderate airway humidity, and the production of vasodilator angiotensin 1-7 by ACE2 are less favorable to the virus entry and/or its development. The meteorological and environmental parameters impacting COVID-19 pandemic should be reintegrated into a whole perspective by taking into account the different factors influencing transmissibility, infectivity and virulence of SARS-CoV-2. To understand the modern enigma represented by COVID-19, an interdisciplinary approach is surely essential.

Fructose-1,6-bisphosphate promotes PI3K and glycolysis in T cells?

We propose that fructose-1,6-bisphosphate (F-1,6-BP) promotes a feedback loop between phosphofructokinase-1 (PFK1), phosphatidylinositol-3-kinase/protein kinase B (PI3K/Akt), and PFK2/PFKFB3, which enhances aerobic glycolysis and sustains effector T (T_eff) cell activation, while oxidative metabolism is concomitantly downregulated. This regulation, promoted by low citrate and mitochondrial ATP synthesis, also sustains the Warburg effect in cancer cells.

New Therapeutic Strategies for Lung Cancer

Non-small cell lung cancer (NSCLC) accounts for approximately 27% of all cancer-related deaths worldwide, thus representing a major health problem [...].

Epidemiology and prognostic factors of pleural empyema

BACKGROUND

Infection of the pleural cavity invariably leads to hospitalisation, and a fatal outcome is not uncommon. Our aim was to study the epidemiology of pleural empyema on a nationwide basis in the whole population and in three subgroups of patients, namely post-lung resection, associated cancer and those with no surgery and no cancer.

METHODS

Data from patients aged ≥18 years hospitalised with a diagnosis of pleural infection in France between January 2013 and December 2017 were retrieved from the medical-administrative national hospitalisation database and retrospectively analysed. Mortality, length of stay and costs were assessed.

RESULTS

There were 25 512 hospitalisations for pleural empyema. The annual rate was 7.15 cases per 100 000 habitants in 2013 and increased to 7.75 cases per 100 000 inhabitants in 2017. The mean age of patients was 62.4±15.6 years and 71.7% were men. Post-lung resection, associated cancer and no surgery-no cancer cases accounted for 9.8%, 30.1% and 60.1% of patients, respectively. These groups were significantly different in terms of clinical characteristics, mortality and risk factors for length of stay, costs and mortality. Mortality was 17.1% in the whole population, 29.5% in the associated cancer group, 17.7% in the post-lung resection group and 10.7% in the no surgery-no cancer group. In the whole population, age, presence of fistula, higher Charlson Comorbidity Index (>3), alcohol abuse, arterial hypertension, hyperlipidaemia, atheroma, atrial fibrillation, performance status >3 and three subgroups of pleural empyema independently predicted mortality.

CONCLUSIONS

Empyema is increasing in incidence. Factors associated with mortality are recent lung resection and associated diagnosis of cancer.

Metabolic Strategies for Inhibiting Cancer Development

The tumor microenvironment is a complex mix of cancerous and noncancerous cells (especially immune cells and fibroblasts) with distinct metabolisms. These cells interact with each other and are influenced by the metabolic disorders of the host. In this review, we discuss how metabolic pathways that sustain biosynthesis in cancer cells could be targeted to increase the effectiveness of cancer therapies by limiting the nutrient uptake of the cell, inactivating metabolic enzymes (key regulatory ones or those linked to cell cycle progression), and inhibiting ATP production to induce cell death. Furthermore, we describe how the microenvironment could be targeted to activate the immune response by redirecting nutrients toward cytotoxic immune cells or inhibiting the release of waste products by cancer cells that stimulate immunosuppressive cells. We also examine metabolic disorders in the host that could be targeted to inhibit cancer development. To create future personalized therapies for targeting each cancer tumor, novel techniques must be developed, such as new tracers for positron emission tomography/computed tomography scan and immunohistochemical markers to characterize the metabolic phenotype of cancer cells and their microenvironment. Pending personalized strategies that specifically target all metabolic components of cancer development in a patient, simple metabolic interventions could be tested in clinical trials in combination with standard cancer therapies, such as short cycles of fasting or the administration of sodium citrate or weakly toxic compounds (such as curcumin, metformin, lipoic acid) that target autophagy and biosynthetic or signaling pathways.

The key role of Warburg effect in SARS-CoV-2 replication and associated inflammatory response

Current mortality due to the Covid-19 pandemic (approximately 1.2 million by November 2020) demonstrates the lack of an effective treatment. As replication of many viruses - including MERS-CoV - is supported by enhanced aerobic glycolysis, we hypothesized that SARS-CoV-2 replication in host cells (especially airway cells) is reliant upon altered glucose metabolism. This metabolism is similar to the Warburg effect well studied in cancer. Counteracting two main pathways (PI3K/AKT and MAPK/ERK signaling) sustaining aerobic glycolysis inhibits MERS-CoV replication and thus, very likely that of SARS-CoV-2, which shares many similarities with MERS-CoV. The Warburg effect appears to be involved in several steps of COVID-19 infection. Once induced by hypoxia, the Warburg effect becomes active in lung endothelial cells, particularly in the presence of atherosclerosis, thereby promoting vasoconstriction and micro thrombosis. Aerobic glycolysis also supports activation of pro-inflammatory cells such as neutrophils and M1 macrophages. As the anti-inflammatory response and reparative process is performed by M2 macrophages reliant on oxidative metabolism, we speculated that the switch to oxidative metabolism in M2 macrophages would not occur at the appropriate time due to an uncontrolled pro-inflammatory cascade. Aging, mitochondrial senescence and enzyme dysfunction, AMPK downregulation and p53 inactivation could all play a role in this key biochemical event. Understanding the role of the Warburg effect in COVID-19 can be essential to developing molecules reducing infectivity, arresting endothelial cells activation and the pro-inflammatory cascade.

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Enhanced aerobic glycolysis supports replication of many viruses including MERS-CoV.

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PI3K/AKT and MAPK/ERK inhibitors arrest MERS-CoV replication.

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This metabolism likely sustains SARS-CoV-2 replication in host cells, in particular airway cells .

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The Warburg effect also supports activation of endothelial cells and pro-inflammatory cells .

Nivolumab increases pulmonary artery pressure in patients treated for non-small cell lung cancer

PURPOSE

The widespread use of Nivolumab results in an increasing number of side effects and adverse events. Herein, we evaluated the impact of Nivolumab on crude and normalized pulmonary artery diameter (PAD).

METHODS

We analyzed clinical, morphometric, pathological and radiological data of lung cancer patients treated by Nivolumab in an 18-month period. Blinded radiological evaluation was performed, by three observers measuring axial PAD and Aorta diameter (AoD) in secondarily matched pre- and post-Nivolumab CT-scans. Correlation between ΔPAD and clinicopathological data was investigated.

RESULTS

59 patients receiving Nivolumab for treatment of advanced lung carcinoma were identified. Pre-and post-Nivolumab comparison of CT-scan measures revealed that mean PAD was 26.3 ± 2.8 mm versus 28.0 ± 3.0 mm (p < 0.001), and mean PAD/AoD ratio was 0.82 ± 0.09 versus 0.87 ± 0.11 (p <  0.001), respectively. Median ΔPAD was 0.05 [0.01-0.122] was significantly higher in hypometabolic patients exhibiting low Rest Energy Expenditure (p = 0.03). Patients exhibiting ΔPAD > 1% had significantly lower serum albumin level (p = 0.03), and higher nutritional risk (p = 0.02), compared to others. Unlike Nivolumab therapy, there was no increase of PAD after chemotherapy in the same cohort of patients with available scans (n = 45, 25.9 ± 2.9 mm pre-chemotherapy versus 25.7 ± 2.4 mm post-chemotherapy, p = 0.51). Anti-PD-1 treatment was associated with immune-related adverse events in 11 (18.6%) cases including 2 cases of life-threatening acute pulmonary hypertension, both exhibiting post-treatment PAD/AoD ratio > 1.

CONCLUSION

Nivolumab is associated to PAD enlargement, a potential marker of pulmonary hypertension, sometimes leading to lethal adverse events. Careful CT-scan and echocardiographic evaluation of PAD should be part of the therapeutic work-up of patients receiving Nivolumab, especially those suffering cancer-associated malnutrition.

[Surgical management of resectable non-small cell lung cancer: Towards new paradigms]

Adapting therapies and providing personalized care for patients with resectable non-small cell lung cancer represent major challenges. This involves integrating several parameters into the patient's management, not only crude pathologic results, but also a better understanding of the mechanisms involved in tumor progression. Many studies have looked at the impact of host and tumor characteristics and their interactions through inflammatory processes or tumor immune environment. Beyond tumor stage, poor nutrition, sarcopenia and inflammatory state have been identified as independent factors that can directly impact postoperative outcome. The development of Enhanced Recovery After Surgery (ERAS), in which patient becomes the main player in their own management, seems to be an interesting answer since it seems to allow a reduction in postoperative complications, length of stay and indirectly reduction in costs. A broader and more complete vision including morphometric evaluation of the patient, physical performances, inflammatory state and nutritional state would provide additional discriminating information which can predict postoperative outcome and help in adapting therapies in a personalized way.

Perspective: Do Fasting, Caloric Restriction, and Diets Increase Sensitivity to Radiotherapy? A Literature Review

Caloric starvation, as well as various diets, has been proposed to increase the oxidative DNA damage induced by radiotherapy (RT). However, some diets could have dual effects, sometimes promoting cancer growth, whereas proposing caloric restriction may appear counterproductive during RT considering that the maintenance of weight is a major factor for the success of this therapy. A systematic review was performed via a PubMed search on RT and fasting, or caloric restriction, ketogenic diet (>75% of fat-derived energy intake), protein starvation, amino acid restriction, as well as the Warburg effect. Twenty-six eligible original articles (17 preclinical studies and 9 clinical noncontrolled studies on low-carbohydrate, high-fat diets popularized as ketogenic diets, representing a total of 77 patients) were included. Preclinical experiments suggest that a short period of fasting prior to radiation, and/or transient caloric restriction during treatment course, can increase tumor responsiveness. These regimens promote accumulation of oxidative lesions and insufficient repair, subsequently leading to cancer cell death. Due to their more flexible metabolism, healthy cells should be less sensitive, shifting their metabolism to support survival and repair. Interestingly, these regimens might stimulate an acute anticancer immune response, and may be of particular interest in tumors with high glucose uptake on positron emission tomography scan, a phenotype associated with poor survival and resistance to RT. Preclinical studies with ketogenic diets yielded more conflicting results, perhaps because cancer cells can sometimes metabolize fatty acids and/or ketone bodies. Randomized trials are awaited to specify the role of each strategy according to the clinical setting, although more stringent definitions of proposed diet, nutritional status, and consensual criteria for tumor response assessment are needed. In conclusion, dietary interventions during RT could be a simple and medically economical and inexpensive method that may deserve to be tested to improve efficiency of radiation.

Lipoic acid decreases breast cancer cell proliferation by inhibiting IGF-1R via furin downregulation

BACKGROUND

Breast cancer is the second most common cancer in the world. Despite advances in therapies, the mechanisms of resistance remain the underlying cause of morbidity and mortality. Lipoic acid (LA) is an antioxidant and essential cofactor in oxidative metabolism. Its potential therapeutic effects have been well documented, but its mechanisms of action (MOA) are not fully understood.

METHODS

The aim of this study is to validate the inhibitory LA effect on the proliferation of various breast cancer cell lines and to investigate the MOA that may be involved in this process. We tested LA effects by ex vivo studies on fresh human mammary tumour samples.

RESULTS

We demonstrate that LA inhibits the proliferation and Akt and ERK signalling pathways of several breast cancer cells. While searching for upstream dysregulations, we discovered the loss of expression of IGF-1R upon exposure to LA. This decrease is due to the downregulation of the convertase, furin, which is implicated in the maturation of IGF-1R. Moreover, ex vivo studies on human tumour samples showed that LA significantly decreases the expression of the proliferation marker Ki67.

CONCLUSION

LA exerts its anti-proliferative effect by inhibiting the maturation of IGF-1R via the downregulation of furin.

Lipoic acid-induced oxidative stress abrogates IGF-1R maturation by inhibiting the CREB/furin axis in breast cancer cell lines

The beneficial effects of lipoic acid (LA) in cancer treatment have been well documented in the last decade. Indeed, LA exerts crucial antiproliferative effects by reducing breast cancer cell viability, cell cycle progression and the epithelial-to-mesenchymal transition (EMT). However, the mechanisms of action (MOA) underlying these antiproliferative effects remain to be elucidated. Recently, we demonstrated that LA decreases breast cancer cell proliferation by inhibiting IGF-1R maturation via the downregulation of the proprotein convertase furin. The aim of the present study was to investigate the MOA by which LA inhibits furin expression in estrogen receptor α (ERα) (+) and (-) breast cancer cell lines. We unveil that LA exerts a pro-oxidant effect on these cell lines, the resulting reactive oxygen species (ROS) generated being responsible for the reduction in the expression of the major (CREB) protein. This transcription factor is overexpressed in many types of cancers and regulates the expression of furin in breast cancer cells independently of ERα, as evidenced herein by the inhibition of furin expression following CREB silencing. Consequently, our findings expose for the first time the complete MOA of LA via the CREB/furin axis leading to inhibition of breast cancer cell proliferation.

Pre-Disease and Pre-Surgery BMI, Weight Loss and Sarcopenia Impact Survival of Resected Lung Cancer Independently of Tumor Stage

Lower pre-surgery Body Mass Index (BMI) and low muscle mass impact negatively long-term survival of non-small cell lung cancer (NSCLC). We investigated their influence on survival after major lung resection for NSCLC.

METHODS

A retrospective analysis of a prospectively collected database was made on 304 consecutive patients.

RESULTS

Underweight, normal, overweight and obese patients represented 7.6%, 51.6%, 28.6%, and 12.6% of the pre-disease population. Weight loss and gain were recorded in 5% and 44.4% of patients, respectively. Low muscle mass was more frequently associated with BMI < 25 kg/m² (p < 0.000001). Overall survival was positively affected by pre-disease (p = 0.036) and pre-surgery (p = 0.017) BMI > 25 kg/m², and, even more, in case of BMI > 25 kg/m² and increasing weight (p = 0.012). Long-term outcome was negatively influenced by low muscle mass (p = 0.042) and weight loss (p = 0.0052) as well as age (p = 0.017), ASA categories (p = 0.025), extent of resection (p = 0.0001), pleural invasion (p = 0.0012) and higher pathologic stage (p < 0.0001). Three stepwise multivariable models confirmed the independent favorable prognostic value of higher pre-disease (RR 0.66[0.49-0.89], p = 0.006) and pre-surgery BMI (RR 0.72[0.54-0.98], p = 0.034), and the absence of low muscle mass (RR 0.56[0.37-0.87], p = 0.0091).

CONCLUSIONS

Body reserves assessed by simple clinical markers impact survival of surgically treated NSCLC. Strategies improving body fat and muscular mass before surgery should be considered.

Costal cartilage resection for the treatment of slipping rib syndrome (Cyriax syndrome) in adults

Background

Slipping rib syndrome is an overlooked cause of low chest or upper abdominal pain. Costal cartilage excision has been described as an effective treatment of this disorder. We review our experience with surgically treated slipping rib syndrome in the adult patient.

Methods

This is a single institution retrospective analysis from January 2000 to March 2019 of adult patients operated on for treatment of a slipping rib syndrome.

Results

Nineteen patients were diagnosed with slipping rib syndrome and underwent costal cartilage excision. All patients presented with unilateral and life disturbing chest pain (8 left sided). In all cases, point tenderness was observed with palpation and hooking maneuver was positive. Each patient underwent imaging and ultrasonography suggested slipping rib syndrome in one case. A mean of 1±0.2 cartilages was excised. Early postoperative course was uneventful in all the cases. Follow-up was complete for all patients over a median of 18.7±12 [3-132] months. At postoperative month 2 follow-up, 15 on 19 patients had complete resolution of their symptoms. At late interviews, 6 out of 19 patients described recurrent pain, whose intensity was significantly lower. We observed significant differences about pre-operative and post-operative visual analog pain (EVA) (8.07±0.75 vs. 2±2.3, P<0.005), weekly pain crises (6.25±2.7 vs. 1.6±2.1, P<0.005) and morphinics consomption (9/19 vs. 2/19, P=0.029). Fourteen patients out of 19 nineteen strongly recommended surgical intervention.

Conclusions

Slipping rib syndrome of the adult is an overlooked cause of chest or abdominal pain which diagnosis and treatment are often delayed. Costal cartilage excision allows short to mid-terms effective and reliable treatment to reduce symptoms and life disturbance but does not exclude late pain recurrence.

Interconnection between Metabolism and Cell Cycle in Cancer

Cell cycle progression and division is regulated by checkpoint controls and sequential activation of cyclin-dependent kinases (CDKs). Understanding of how these events occur in synchrony with metabolic changes could have important therapeutic implications. For biosynthesis, cancer cells enhance glucose and glutamine consumption. Inactivation of pyruvate kinase M2 (PKM2) promotes transcription in G1 phase. Glutamine metabolism supports DNA replication in S phase and lipid synthesis in G2 phase. A boost in glycolysis and oxidative metabolism can temporarily furnish more ATP when necessary (G1/S transition, segregation of chromosomes). Recent studies have shown that a few metabolic enzymes [PKM2, 6-phosphofructo-2-kinase/fructose-2,6-biphosphatase (PFKFB3), GAPDH] also periodically translocate to the nucleus and oversee cell cycle regulators or oncogene expression (c-Myc). Targeting these metabolic enzymes could increase the response to CDK inhibitors (CKIs).

Citrate targets FBPase and constitutes an emerging novel approach for cancer therapy

Gao-Min Liu and Yao-Ming Zhang recently published a review entitled «Targeting FBPase is an emerging novel approach for cancer therapy» (Liu and Zhang in Cancer Cell Int 18:36, 2018). In this paper, the authors highlighted how the down regulation or inactivation of FBPase, a rate limiting enzyme of gluconeogenesis, can promote the Warburg effect and cancer growth. In contrast, activation of this enzyme demonstrates anti-cancer effects and may appear as emerging novel approach for cancer therapy. Among the potential activators of FBP listed by Liu and Zhang, citrate was surprisingly not mentioned although it is an activator of FBPase, also demonstrating various anti-cancer effects in pre-clinical studies. Thus, citrate should be tested as a new therapeutic strategy, in particular in clinical studies.

Is There a Place for Thoracoscopic Enucleation of Esophageal Gastrointestinal Stromal Tumors?

BACKGROUND

 Esophageal gastrointestinal stromal tumors (E-GISTs) represent less than 1% of all GISTs. The rarity of this lesion precludes the realization of randomized studies, and its treatment remains a matter of debate. We aimed to evaluate the feasibility of enucleation by video-assisted thoracic surgery (VATS) for low- to intermediate-risk E-GIST.

METHODS

 We performed a retrospective review of patients treated by enucleation through VATS between January 2004 and January 2014 and reviewed the literature.

RESULTS

 We included five patients (four men and one woman). Mean age was 53 years (range: 49-79). Three patients were diagnosed because of dysphagia and two others incidentally. The diagnosis was made by immunostaining demonstrating CD117 expression on tumor cells. The mitotic index of all E-GISTs was low (≤ 5 per 50 high-power field). Median postoperative follow-up was 5.5 years, and there was no recurrence.

CONCLUSION

 Thoracoscopic enucleation of E-GIST seems to represent a valuable option as the postoperative morbidity/mortality is low and the oncological outcome is good for low-to-intermediate grade of malignity tumors.This is a retrospective study focused on minimally invasive treatment of E-GIST. We evaluated the feasibility of VATS enucleation of low-to-medium grade of malignity E-GIST.

How the Warburg effect supports aggressiveness and drug resistance of cancer cells?

Cancer cells employ both conventional oxidative metabolism and glycolytic anaerobic metabolism. However, their proliferation is marked by a shift towards increasing glycolytic metabolism even in the presence of O₂ (Warburg effect). HIF1, a major hypoxia induced transcription factor, promotes a dissociation between glycolysis and the tricarboxylic acid cycle, a process limiting the efficient production of ATP and citrate which otherwise would arrest glycolysis. The Warburg effect also favors an intracellular alkaline pH which is a driving force in many aspects of cancer cell proliferation (enhancement of glycolysis and cell cycle progression) and of cancer aggressiveness (resistance to various processes including hypoxia, apoptosis, cytotoxic drugs and immune response). This metabolism leads to epigenetic and genetic alterations with the occurrence of multiple new cell phenotypes which enhance cancer cell growth and aggressiveness. In depth understanding of these metabolic changes in cancer cells may lead to the development of novel therapeutic strategies, which when combined with existing cancer treatments, might improve their effectiveness and/or overcome chemoresistance.

A Simple Method to Optimize the Effectiveness of Chemotherapy: Modulation of Glucose Intake During Chemotherapy

BACKGROUND/AIM

Cancer cells consume high amounts of glucose to produce ATP and molecules entering biosynthesis. Numerous experimental studies have demonstrated that glucose deprivation and/or glycolysis inhibition arrest cancer cell growth and may increase the efficiency of cytotoxic drugs. In contrast, increasing glycolysis in tumor-infiltrating lymphocytes (TILs) activates these cells that destroy cancer cells. We propose to increase the efficiency of chemotherapy by modulating glucose intake during the course of chemotherapy.

MATERIALS AND METHODS

Glucose and caloric intake should be drastically reduced the day before and during chemotherapy administration to deprive cancer cells of ATP and molecules required to repair cytotoxic lesions. Few hours after chemotherapy, glucose and caloric intake should be drastically increased for few days to promote the activation of TILs that reinforce the destruction of cancer cells.

RESULTS

This strategy could improve the results of chemotherapy by first enhancing cytotoxic stress against tumor cells and then promoting activation of the anti-cancer immune response.

CONCLUSION

The modulation of glucose intake during chemotherapy should be tested clinically. The proposed scheme is simple, surely easier to follow than a strict chronic diet, and should avoid weight loss.

Do atmospheric conditions influence the first episode of primary spontaneous pneumothorax?

OBJECTIVES

Several studies suggest that changes in airway pressure may influence the onset of primary spontaneous pneumothorax (PSP). The aim of this study was to investigate the influence of atmospheric changes on the onset of the first episode of PSP.

METHODS

We retrospectively analysed cases of pneumothorax admitted to our department between 1 January 2009 and 31 October 2013. Patients with recurrent pneumothorax, traumatic pneumothorax, older than 35 years or presenting history of underlying pulmonary disease were excluded. Meteorological data were collected from the Météo-France archives. Variation (Δ) of mean atmospheric pressure, and relative humidity, were calculated for each day between the day at which symptoms began (D-day), the day before first symptoms (D-1), 2 days before the first symptoms (D-2) and 3 days before the first symptoms (D-3).

RESULTS

Six hundred and thirty-eight cases of pneumothorax were observed during the period of this study; 106 of them (16.6%) were a first episode of PSP. We did not observe any significant differences between days with or without PSP admission for any of the weather parameters that we tested. We could not find any thresholds in the variation of atmospheric pressure that could be used to determine the probability of PSP occurrence.

CONCLUSIONS

Variation of atmospheric pressure, relative humidity, rainfall, wind speed and temperature were not significantly related to the onset of the first episode of PSP in healthy patients. These results suggest that the scientific community should focus on other possible aetiological factors than airway pressure modifications.

How do glycolytic enzymes favour cancer cell proliferation by nonmetabolic functions?

Cancer cells enhance their glycolysis, producing lactate, even in the presence of oxygen. Glycolysis is a series of ten metabolic reactions catalysed by enzymes whose expression is most often increased in tumour cells. HKII and phosphoglucose isomerase (PGI) have mainly an antiapoptotic effect; PGI and glyceraldehyde-3-phosphate dehydrogenase activate survival pathways (Akt and so on); phosphofructokinase 1 and triose phosphate isomerase participate in cell cycle activation; aldolase promotes epithelial mesenchymal transition; PKM2 enhances various nuclear effects such as transcription, stabilisation and so on. This review outlines the multiple non-glycolytic roles of glycolytic enzymes, which are essential for promoting cancer cells' survival, proliferation, chemoresistance and dissemination.

Migration of a Kirschner pin from the shoulder to the lung, requiring surgery

A 62-year-old woman underwent a reduction of a proximal reduced humeral fracture, which was fixed by 3 Kirschner pins. One year later, the orthopedic surgeon failed to remove one of the wires. The patient was lost to follow-up, and 4 years later, she presented with hemoptysis, revealing migration of the pin to the lung. The pin was removed through a thoracotomy. Migration to the lung is often revealed by hemoptysis or pneumothorax. Close follow-up and early removal of the pins are mandatory.

A misleading cause of pseudo-thymic tumor in ectopic Cushing's syndrome

A 27-year-old man was referred with typical features of severe Cushing's syndrome. A bilateral adrenalectomy was performed. Three months later, a triangular nodular mediastinal enlargement, evocative of a right anterior thymic tumor, was discovered. Thymectomy was undertaken. Histological examination revealed diffuse thymic hyperplasia with negative immunostaining for adrenocorticotropic hormone. Five years later, a right endobronchial tumor corresponding to a carcinoid tumor was removed.

Metabolic treatment of cancer: intermediate results of a prospective case series

BACKGROUND

The combination of hydroxycitrate and lipoic acid has been demonstrated by several laboratories to be effective in reducing murine cancer growth.

PATIENTS AND METHODS

All patients had failed standard chemotherapy and were offered only palliative care by their referring oncologist. Karnofsky status was between 50 and 80. Life expectancy was estimated to be between 2 and 6 months. Ten consecutive patients with chemoresistant advanced metastatic cancer were offered compassionate metabolic treatment. They were treated with a combination of lipoic acid at 600 mg i.v. (Thioctacid), hydroxycitrate at 500 mg t.i.d. (Solgar) and low-dose naltrexone at 5 mg (Revia) at bedtime. Primary sites were lung carcinoma (n=2), colonic carcinoma (n=2), ovarian carcinoma (n=1), esophageal carcinoma (n=1), uterine sarcoma (n=1), cholangiocarcinoma (n=1), parotid carcinoma (n=1) and unknown primary (n=1). The patients had been heavily pre-treated. One patient had received four lines of chemotherapy, four patients three lines, four patients two lines and one patient had received radiation therapy and chemotherapy. An eleventh patient with advanced prostate cancer resistant to hormonotherapy treated with hydroxycitrate, lipoic acid and anti-androgen is also reported.

RESULTS

One patient was unable to receive i.v. lipoic acid and was switched to oral lipoic acid (Tiobec). Toxicity was limited to transient nausea and vomiting. Two patients died of progressive disease within two months. Two other patients had to be switched to conventional chemotherapy combined with metabolic treatment, one of when had a subsequent dramatic tumor response. Disease in the other patients was either stable or very slowly progressive. The patient with hormone-resistant prostate cancer had a dramatic fall in Prostate-Specific Antigen (90%), which is still decreasing.

CONCLUSION

These very primary results suggest the lack of toxicity and the probable efficacy of metabolic treatment in chemoresistant advanced carcinoma. It is also probable that metabolic treatment enhances the efficacy of cytotoxic chemotherapy. These results are in line with published animal data. A randomized clinical trial is warranted.

Morbidity, mortality and survival after 110 consecutive bilobectomies over 12 years

OBJECTIVES

To analyse statistical aspects of mortality, morbidity and survival after bilobectomy (BT), an operation rarely studied in the literature.

METHODS

One hundred and ten cases were studied, comprising 58 upper-middle bilobectomies and 52 lower-middle bilobectomies performed between 1999 and 2010. Indications were of 9 benign diseases, 12 carcinoid tumours, 5 metastases and 84 non-small cell lung cancers (2 stage 0; 34 stage I; 22 stage II; 25 stage III and 1 stage IV).

RESULTS

Mortality was nil. Twenty-six percent of patients experienced significant morbidity, influenced in multivariate analysis by the presence of three or more comorbidities (P = 0.03) and by a forced expiratory volume in 1 s of <60% (P = 0.01). Lower-middle BT was associated with more postoperative complications than upper-middle BT (P = 0.012). The 5-year survival rate of patients with non-small cell lung carcinoma was 82% in stage I, 59% in stage II and 20% in stage IIIA. Survival was significantly influenced by stage (P = 0.0018) and tobacco weaning (P = 0.0012).

CONCLUSIONS

BT can be achieved with low mortality, and survival results that are comparable with those unregistered after standard lobectomy. However, almost one quarter of patients experienced significant postoperative complications. Surgical techniques aiming to reduce residual pleural space should be especially considered after lower-middle BT, due to the highest morbidity being associated with this procedure.

siPGK1 sensitizes chemoresistant human ovarian cancer cell lines to cisplatin

Enhanced glycolysis provides essential intermediates for cancer cell proliferation. Its inhibition could be a promising approach for destroying tumors, especially those developing in hypoxic conditions, which are presumably the most chemoresistant. In hypoxic cells, glycolysis provides the main part of ATP. Phosphoglycerate kinase-1 (PGK1) catalyzes a crucial reaction of glycolysis that reconstitutes the two molecules of ATP previously consumed. PGK1 inhibition could arrest growth or kill hypoxic and/or chemoresistant cells. We tested siPGK1 transfection in two human ovarian cancer cells lines of increasing chemoresistance, and showed that: Expression of PGK1 was significantly reduced and associated with blockade of cell growth in the G(1) phase; siPGK1 associated with cisplatin was more effective than cisplatin-alone at inhibiting proliferation of chemoresistant cells; siPGK1 -alone and -associated with cisplatin strongly increased expression of the BH3-only pro-apoptotic protein BCL-2 Interacting Mediator of cell death (BIM). PGK1 might be a key target for sensitizing chemoresistant cells to cisplatin.

Pulmonary botryomycosis on a lung cavity: a rare pulmonary infection mimicking cancer

Lung botryomycosis is a rare disease. We report what is to our knowledge the first case occurring on a lung cavity. In a 42-year-old man suffering asthenia and cough, a chest radiograph revealed a right upper lobe opacity. Computed tomography scan showed a necrotic mass which was also spiculated. Repeated research for Mycobacterium tuberculosis was negative. The patient underwent a lobectomy. Histological and bacteriological examinations made the diagnosis of botryomycosis, because the cavity presented numerous colonies of pyogenic Fusobacterium nucleatum bacteria. Botryomycosis is a difficult diagnosis that clinically mimics actinomycosis, tuberculosis or cancer. In most cases, surgery is necessary to assess diagnosis and treatment.

Understanding the central role of citrate in the metabolism of cancer cells

Cancers cells strongly stimulate glycolysis and glutaminolysis for their biosynthesis. Pyruvate derived from glucose is preferentially diverted towards the production of lactic acid (Warburg effect). Citrate censors ATP production and controls strategic enzymes of anabolic and catabolic pathways through feedback reactions. Mitochondrial citrate diffuses in the cytosol to restore oxaloacetate and acetyl-CoA. Whereas acetyl-CoA serves de novo lipid synthesis and histone acetylation, OAA is derived towards lactate production via pyruvate and / or a vicious cycle reforming mitochondrial citrate. This cycle allows cancer cells to burn their host's lipid and protein reserves in order to sustain their own biosynthesis pathways. In vitro, citrate has demonstrated anti-cancer properties when administered in excess, sensitizing cancer cells to chemotherapy. Understanding its central role is of particular relevance for the development of new strategies for counteracting cancer cell proliferation and overcoming chemoresistance.

Citrate induces apoptotic cell death: a promising way to treat gastric carcinoma?

Gastric carcinoma is frequent, particularly in China, and therapy is often inefficient. Because cancer cells are partly or mainly dependent on glycolysis to generate adenosine triphosphate ATP (Warburg effect) and/or to produce precursors (of lipid, nucleotides, etc.) for building new cells, any inhibition of glycolysis may slow down the cell proliferation and/or may kill cells. The antitumor effect of citrate, an anti-glycolytic agent inhibiting phosphofructokinase (PFK) was tested on two human gastric carcinoma cell lines.

MATERIALS AND METHODS

Cell viability and morphology were assessed after 24-72 h exposure to citrate (5, 10, 220 mM). Apoptosis was assessed by annexin V-FITC/PI staining and Western immunobloting.

RESULTS

A 3-day continuous exposure to citrate led to near destruction of the cell population in both cell lines, apoptotic cell death occurred through the mitochondrial pathway in a dose- and time-dependent manner, associated with the reduction of the anti-apoptotic Mcl-1 protein in both lines.

CONCLUSION

Citrate demonstrates strong cytotoxic activity against two gastric cancer lines, leading to an early diminution of expression of Mcl-1 and to massive apoptotic cell death involving the mitochondrial pathway.

Downregulation of Bcl-xL and Mcl-1 is sufficient to induce cell death in mesothelioma cells highly refractory to conventional chemotherapy

Malignant pleural mesothelioma (MPM) is an aggressive tumor with poor prognosis and limited response to platinum-based chemotherapy. Several lines of evidence support a role for the anti-apoptotic protein Bcl-x(L) in MPM chemoresistance. Since it has been recently suggested that Mcl-1 cooperates with Bcl-x(L) for protection against cell death, we investigated the response of mesothelioma cell lines to the downregulation of Bcl-x(L) (alone or in combination with cisplatin) and the potential interest of its concomitant inhibition with that of Mcl-1. Using RNA interference, we showed that Bcl-x(L) depletion sensitized two highly chemoresistant mesothelioma cell lines to cisplatin and that under this treatment, one cell line, MSTO-211H, displayed an apoptotic type of cell death, whereas the other, NCI-H28, evidenced mainly necrotic-type cell death. Otherwise, the inhibition of Mcl-1 by cisplatin may contribute to this induction of cell death observed after Bcl-x(L) downregulation. Strikingly, we observed that the simultaneous inhibition of Bcl-x(L) and Mcl-1 using small interfering RNA (siRNA) induced a massive cell death in the absence of chemotherapy and was sufficient to avoid escape to treatment in MSTO-211H cells. In NCI-H28, the addition of a low cisplatin concentration allowed to impede the long-term recovery observed after treatment by the siRNA combination. Together, these findings provide a strong molecular basis for the clinical evaluation of therapies targeting both Bcl-x(L) and Mcl-1, alone or in combination with conventional chemotherapy, for the treatment of MPM.

Social-behavioural functioning in paediatric chronic kidney disease

Background The social-behavioural functioning of children and adolescents with chronic kidney disease (CKD) is not well studied and not fully understood, with available studies reflecting a mixed set of findings. The primary purpose of this paper is to compare the social-behavioural functioning of children with CKD with typical controls using multiple raters. A secondary analysis also examines the impact of disease severity on social-behavioural functioning. Methods Parental ratings and self-reports on the Behavior Assessment System for Children were obtained from a patient sample of 26 children and adolescents with CKD. This sample was comprised of those with end-stage renal disease (end-stage renal disease; n= 13) and those with chronic renal insufficiency (n= 13). For comparison, a typically developing control group (n= 33) also was ascertained. Results While behaviour ratings by parents and children fell within the average range, parent ratings showed an increased number of internalizing symptoms when compared with the CKD Group. Exploratory analyses revealed parental ratings showing more specific concerns on the Behavior Assessment System for Children individual clinical scales of Anxiety, Depression and Somatization. No differences were observed between the groups on the children's self-ratings, or in terms of numbers of children falling above the 90th percentile for both parent and child ratings. Secondary analyses did not produce any group differences between the chronic renal insufficiency and end-stage renal disease severity groupings. Conclusions These findings failed to show the presence of social-behavioural difficulties in children with CKD, although there may be specific concerns for the presence of internalizing symptoms as per parent ratings. These findings suggest the need for follow-up of the subtle affective symptoms that might be present in children with CKD as recognizing these subthreshold social-behavioural symptoms may be a critical part of their overall clinical care.

Effect of citrate on malignant pleural mesothelioma cells: a synergistic effect with cisplatin

BACKGROUND

Because cancer cells are partly or mainly dependent on glycolysis to generate ATP (Warburg effect), any inhibition of glycolysis may slow down their proliferation or kill them.

MATERIALS AND METHODS

The anti-tumor effect of citrate, an inhibitor of phosphofructokinase, was tested on particularly chemoresistant MSTO-211H human mesothelioma cells.

RESULTS

A 3-day continuous exposure to citrate led to apoptotic cell death via a mitochondrial pathway, associated with a reduction of anti-apoptotic protein Bcl-x(L) and Mcl-1 expression. However, when citrate was removed, the remaining cells resumed their proliferation. The treatment of cells with a non-cytotoxic dose of cisplatin at the end of the citrate exposure led to a strong cytotoxicity, almost all cells being killed.

CONCLUSION

Depletion of ATP, diminution of the expression of the anti-apoptotic proteins and inhibition of hexokinase secondary to inhibition of phosphofructokinase by citrate may explain the cytotoxic activity of this molecule and its synergistic effect with cisplatin.

Novel therapy for malignant pleural mesothelioma based on anti-energetic effect: an experimental study using 3-Bromopyruvate on nude mice

BACKGROUND

Most cancer cells exhibit increased anaerobic glycolysis and use this metabolic pathway for the generation of ATP as a main source of energy. This impaired metabolism of glucose, leading to the secretion of lactic acid even in the presence of oxygen, is named the Warburg effect. Because cancer cells are partly or mainly dependent on such a pathway to generate ATP, inhibition of glycolysis may slow down the proliferation or kill cells.

MATERIALS AND METHODS

The effect of 3-Bromopyruvate (3-BrPA) alone or associated to cisplatin on nude mice presenting intraperitoneal carcinomatosis developed after intraperitoneal injection of human mesothelioma cells (MSTO-211H) was investigated.

RESULTS

3-BrPA significantly prolonged survival of animals. Combined with cisplatin, it demonstrated significant benefit on survival whereas cisplatin alone had no or a mild effect.

CONCLUSION

3-BrPA may thus constitute an interesting novel anticancer drug that could be tested in humans.

A single 24F Blake drain after wedge resection or lobectomy: a study on 100 consecutive cases

OBJECTIVE

To evaluate the results of chest drainage using one 24F Blake drain after standard thoracic operations (wedge resection and lobectomy).

METHODS

In 2005, 100 consecutive patients underwent drainage of their pleural cavity following lobectomy or wedge resection(s). There were 70 men and 30 women, with a mean age of 55 years (17-83). There were 47 lobectomies (23 upper, 5 middle, 19 lower), 3 bilobectomies (2 right upper and middle, 1 right lower and middle), and 2 anatomical segmentectomies. All these anatomical resections were performed by standard thoracotomy, mainly for cancer diseases (45 cases). Furthermore, 48 atypical resections by single or multiple wedge(s) were realized, 20 of them by VATS. They included 14 various benign diseases, 16 malignant diseases, 8 significant emphysema bullous, and 10 blebs. Chest X rays were performed regularly in the postoperative period to detect residual pleural effusion or pneumothorax necessitating additional drainage or reoperation. Patients were controlled one month after discharge.

RESULTS

One patient with pleural carcinosis died of pulmonary embolus on day 8. Neither replacement of chest tube nor reoperation was necessary for pleural space problems. Median duration of drainage was 5 days (3-15), 6 days after lobectomy and 4 days after wedge resection. In 15 cases, the duration of drainage was more than 8 days: 11 persistent air leaks and 4 drainages exceeding 150-200 cm3 daily. Ninety percent of patients were discharged the day following the drain removal.

CONCLUSIONS

Postoperative courses after standard thoracic procedures using a single 24F Blake drainage appear similar to that accounting after a classical semi-rigid drainage. Such single drainage may appear now as an acceptable option. The flexible quality of the drain, its reduced caliber, and the character unique of the drainage, may contribute to improve comfort of the operated patients.