Doxycycline attenuates breast cancer related inflammation by decreasing plasma lysophosphatidate concentrations and inhibiting NF-κB activation

Untargeted serum and gastric metabolomics and network pharmacology analysis reveal the superior efficacy of zingiberis rhizoma recens-/euodiae fructus-processed Coptidis Rhizoma on gastric ulcer rats

ETHNOPHARMACOLOGICAL RELEVANCE

Zingiberis rhizoma recens-/wine-/euodiae fructus-processed Coptidis Rhizoma (CR, zCR/wCR/eCR) are the commonly used processed products of CR in clinic. After being processed with different excipients, the efficacy of CR will change accordingly. I.e., wCR could resolve excessive heat of the upper energizer, zCR could eliminate gastric heat and harmonize the stomach, eCR could smooth the liver and harmonize the stomach. However, the underlying mechanisms were still unclear.

AIM OF THE STUDY

To further verify the differential efficacy of the three processed CR products and compare the mechanisms on gastric ulcer.

MATERIAL AND METHODS

First, a GU model, whose onset is closely related to the heat in stomach and the disharmony between liver and stomach, was established, and the therapeutic effects of zCR/wCR/eCR/CR were evaluated by pathologic observation and measurement of cytokine levels. Second, metabolomics analysis and network pharmacology were conducted to reveal the differential intervening mechanism of zCR/eCR on GU. Third, the predicted mechanisms from metabolomics analysis and network pharmacology were validated using western blotting, flow cytometry and immunofluorescence.

RESULTS

zCR/wCR/eCR/CR could alleviate the pathologic damage to varying degrees. In metabolomics research, fewer metabolic pathways were enriched in serum samples, and most of them were also present in the results of gastric tissue samples. The gastroprotective, anti-inflammatory, antioxidant, and anti-apoptotic effects of zCR/wCR/eCR/CR might be due to their interference on histidine, arachidonic acid, and glycerophospholipids metabolism. Quantitative results indicated that zCR/eCR had a better therapeutic effect than wCR/CR in treating GU. A comprehensive analysis of metabolomics and network pharmacology revealed that zCR and eCR exerted anti-GU effects via intervening in five core targets, including AKT, TNF, IL6, IL1B and PPARG. In the validation experiment, zCR/eCR could significantly reverse the abnormal expression of proteins related to apoptosis, inflammation, oxidative stress, gastric function, as well as the PI3K/AKT signaling pathways.

CONCLUSION

zCR and eCR could offer gastroprotective benefits by resisting inflammation and apoptosis, inhibiting gastric-acid secretion, as well as strengthening gastric mucosal defense and antioxidant capacity. Integrating network pharmacology and metabolomics analysis could reveal the acting mechanism of drugs and promote the development of medications to counteract GU.

Breast Tumor Metastasis and Its Microenvironment: It Takes Both Seed and Soil to Grow a Tumor and Target It for Treatment

Metastasis remains a major challenge in treating breast cancer. Breast tumors metastasize to organ-specific locations such as the brain, lungs, and bone, but why some organs are favored over others remains unclear. Breast tumors also show heterogeneity, plasticity, and distinct microenvironments. This contributes to treatment failure and relapse. The interaction of breast cancer cells with their metastatic microenvironment has led to the concept that primary breast cancer cells act as seeds, whereas the metastatic tissue microenvironment (TME) is the soil. Improving our understanding of this interaction could lead to better treatment strategies for metastatic breast cancer. Targeted treatments for different subtypes of breast cancers have improved overall patient survival, even with metastasis. However, these targeted treatments are based upon the biology of the primary tumor and often these patients' relapse, after therapy, with metastatic tumors. The advent of immunotherapy allowed the immune system to target metastatic tumors. Unfortunately, immunotherapy has not been as effective in metastatic breast cancer relative to other cancers with metastases, such as melanoma. This review will describe the heterogeneic nature of breast cancer cells and their microenvironments. The distinct properties of metastatic breast cancer cells and their microenvironments that allow interactions, especially in bone and brain metastasis, will also be described. Finally, we will review immunotherapy approaches to treat metastatic breast tumors and discuss future therapeutic approaches to improve treatments for metastatic breast cancer.

A combined opposite targeting of p110δ PI3K and RhoA abrogates skin cancer

Malignant melanoma is the most aggressive and deadly skin cancer with an increasing incidence worldwide whereas SCC is the second most common non-melanoma human skin cancer with limited treatment options. Here we show that the development and metastasis of melanoma and SCC cancers can be blocked by a combined opposite targeting of RhoA and p110δ PI3K. We found that a targeted induction of RhoA activity into tumours by deletion of p190RhoGAP-a potent inhibitor of RhoA GTPase-in tumour cells together with adoptive macrophages transfer from δD910A/D910A mice in mice bearing tumours with active RhoA abrogated growth progression of melanoma and SCC tumours. Τhe efficacy of this combined treatment is the same in tumours lacking activating mutations in BRAF and in tumours harbouring the most frequent BRAF(V600E) mutation. Furthermore, the efficiency of this combined treatment is associated with decreased ATX expression in tumour cells and tumour stroma bypassing a positive feedback expression of ATX induced by direct ATX pharmacological inactivation. Together, our findings highlight the importance of targeting cancer cells and macrophages for skin cancer therapy, emerge a reverse link between ATX and RhoA and illustrate the benefit of p110δ PI3K inhibition as a combinatorial regimen for the treatment of skin cancers.

Infliximab, a Monoclonal Antibody against TNF-α, Inhibits NF-κB Activation, Autotaxin Expression and Breast Cancer Metastasis to Lungs

An inflammatory milieu in the tumor microenvironment leads to immune evasion, resistance to cell death, metastasis and poor prognosis in breast cancer patients. TNF-α is a proinflammatory cytokine that regulates multiple aspects of tumor biology from initiation to progression. TNF-α-induced NF-κB activation initiates inflammatory pathways, which determine cell survival, death and tumor progression. One candidate pathway involves the increased secretion of autotaxin, which produces lysophosphatidate that signals through six G-protein-coupled receptors. Significantly, autotaxin is one of the 40-50 most upregulated genes in metastatic tumors. In this study, we investigated the effects of TNF-α by blocking its action with a monoclonal antibody, Infliximab, and studied the effects on autotaxin secretion and tumor progression. Infliximab had little effect on tumor growth, but it decreased lung metastasis by 60% in a syngeneic BALB/c mouse model using 4T1 breast cancer cells. Infliximab-treated mice also showed a decrease in proliferation and metastatic markers like Ki-67 and vimentin in tumors. This was accompanied by decreases in NF-κB activation, autotaxin expression and the concentrations of plasma and tumor cytokines/chemokines which are involved in metastasis. We also demonstrated a positive correlation of TNF-α -NF-κB and ATX expression in breast cancer patients using cancer databases. Studies in vitro showed that TNF-α-induced NF-κB activation increases autotaxin expression and the clone forming ability of 4T1 breast cancer cells. This report highlights the potential role of Infliximab as an additional approach to attenuate signaling through the autotaxin-lysophosphatidate-inflammatory cycle and decrease mortality from metastatic cancer.

Increased risk of chronic fatigue syndrome following infection: a 17-year population-based cohort study

BACKGROUND

Previous serological studies have indicated an association between viruses and atypical pathogens and Chronic Fatigue Syndrome (CFS). This study aims to investigate the correlation between infections from common pathogens, including typical bacteria, and the subsequent risk of developing CFS. The analysis is based on data from Taiwan's National Health Insurance Research Database.

METHODS

From 2000 to 2017, we included a total of 395,811 cases aged 20 years or older newly diagnosed with infection. The cases were matched 1:1 with controls using a propensity score and were followed up until diagnoses of CFS were made.

RESULTS

The Cox proportional hazards regression analysis was used to estimate the relationship between infection and the subsequent risk of CFS. The incidence density rates among non-infection and infection population were 3.67 and 5.40 per 1000 person-years, respectively (adjusted hazard ratio [HR] = 1.5, with a 95% confidence interval [CI] 1.47-1.54). Patients infected with Varicella-zoster virus, Mycobacterium tuberculosis, Escherichia coli, Candida, Salmonella, Staphylococcus aureus and influenza virus had a significantly higher risk of CFS than those without these pathogens (p < 0.05). Patients taking doxycycline, azithromycin, moxifloxacin, levofloxacin, or ciprofloxacin had a significantly lower risk of CFS than patients in the corresponding control group (p < 0.05).

CONCLUSION

Our population-based retrospective cohort study found that infection with common pathogens, including bacteria, viruses, is associated with an increased risk of developing CFS.

The tale of antibiotics beyond antimicrobials: Expanding horizons

Antibiotics had proved to be a godsend for mankind since their discovery. They were once the magical solution to the vexing problem of infection-related deaths. German scientist Paul Ehrlich had termed salvarsan as the silver bullet to treatsyphilis.As time passed, the magic of newly discovered silver bullets got tarnished with raging antibiotic resistance among bacteria and associated side-effects. Still, antibiotics remain the primary line of treatment for bacterial infections. Our understanding of their chemical and biological activities has increased immensely with advancement in the research field. Non-antibacterial effects of antibiotics are studied extensively to optimise their safer, broad-range use. These non-antibacterial effects could be both useful and harmful to us. Various researchers across the globe including our lab are studying the direct/indirect effects and molecular mechanisms behind these non-antibacterial effects of antibiotics. So, it is interesting for us to sum up the available literature. In this review, we have briefed the possible reason behind the non-antibacterial effects of antibiotics, owing to the endosymbiotic origin of host mitochondria. We further discuss the physiological and immunomodulatory effects of antibiotics. We then extend the review to discuss molecular mechanisms behind the plausible use of antibiotics as anticancer agents.

Emerging Roles of Lysophosphatidic Acid in Macrophages and Inflammatory Diseases

Lysophosphatidic acid (LPA) is a bioactive phospholipid that regulates physiological and pathological processes in numerous cell biological functions, including cell migration, apoptosis, and proliferation. Macrophages are found in most human tissues and have multiple physiological and pathological functions. There is growing evidence that LPA signaling plays a significant role in the physiological function of macrophages and accelerates the development of diseases caused by macrophage dysfunction and inflammation, such as inflammation-related diseases, cancer, atherosclerosis, and fibrosis. In this review, we summarize the roles of LPA in macrophages, analyze numerous macrophage- and inflammation-associated diseases triggered by LPA, and discuss LPA-targeting therapeutic strategies.

CRIF1 siRNA-Encapsulated PLGA Nanoparticles Suppress Tumor Growth in MCF-7 Human Breast Cancer Cells

Mitochondrial oxidative phosphorylation (OXPHOS) system dysfunction in cancer cells has been exploited as a target for anti-cancer therapeutic intervention. The downregulation of CR6-interacting factor 1 (CRIF1), an essential mito-ribosomal factor, can impair mitochondrial function in various cell types. In this study, we investigated whether CRIF1 deficiency induced by siRNA and siRNA nanoparticles could suppress MCF-7 breast cancer growth and tumor development, respectively. Our results showed that CRIF1 silencing decreased the assembly of mitochondrial OXPHOS complexes I and II, which induced mitochondrial dysfunction, mitochondrial reactive oxygen species (ROS) production, mitochondrial membrane potential depolarization, and excessive mitochondrial fission. CRIF1 inhibition reduced p53-induced glycolysis and apoptosis regulator (TIGAR) expression, as well as NADPH synthesis, leading to additional increases in ROS production. The downregulation of CRIF1 suppressed cell proliferation and inhibited cell migration through the induction of G0/G1 phase cell cycle arrest in MCF-7 breast cancer cells. Similarly, the intratumoral injection of CRIF1 siRNA-encapsulated PLGA nanoparticles inhibited tumor growth, downregulated the assembly of mitochondrial OXPHOS complexes I and II, and induced the expression of cell cycle protein markers (p53, p21, and p16) in MCF-7 xenograft mice. Thus, the inhibition of mitochondrial OXPHOS protein synthesis through CRIF1 deletion destroyed mitochondrial function, leading to elevated ROS levels and inducing antitumor effects in MCF-7 cells.

Doxycycline-Induced Changes in Circulating MMP or TIMP2 Levels Are Not Associated with Skeletal-Related Event-Free or Overall Survival in Patients with Bone Metastases from Breast Cancer

Doxycycline is often used as a promoter of inducible gene expression in preclinical models; however, it can also have direct effects on tumor growth and survival. This is due in part to its ability to inhibit cell invasion and regulate matrix metalloproteinase (MMP) expression. Given that doxycycline is also osteotropic, a clinical study to assess its effects on modulation of tumor progression or prevention of skeletal-related events (SRE) in patients with bone metastases from breast cancer (the Achilles trial) was undertaken. Patients received 100 mg of oral doxycycline twice daily for 12 weeks, with serum obtained at baseline and 4, 8 and 12 weeks post-initiation of doxycycline treatment. Exploratory analysis of the effects of doxycycline on circulating levels of MMP or tissue inhibitor of matrix metalloproteinase 2 (TIMP2) was performed in enrolled patients. Statistically significant associations were observed between MMP2, MMP9 and TIMP2 at baseline with significant associations maintained between absolute levels and changes in levels of MMP2 and TIMP2 at weeks 4-12 post initiation of doxycycline. Treatment with doxycycline generally resulted in decreases in MMP2 and MMP9 levels with concurrent upregulation of TIMP2 at 12 weeks post-initiation of doxycycline treatment. Despite this, we observed no association with the levels of any of these factors with either SRE-free or overall survival in this patient cohort. In summary, despite observing hypothesized effects of doxycycline administration on surrogate markers of its anti-tumor activity, measures of circulating levels of these biomarkers were not prognostic in this patient population.

Doxycycline inhibits the progression of metastases in early-stage osteosarcoma by downregulating the expression of MMPs, VEGF and ezrin at primary sites

INTRODUCTION

Osteosarcoma (OS) is the most common primary osseous malignant tumour, with high propensity to metastasise in lungs. Pulmonary micro-metastases are present in up to 80% of patients at initial diagnosis and they are associated with significantly worse prognosis. Doxycycline (Dox) is a synthetic tetracycline that has been shown to have anti-cancer properties in vitro and in vivo, and inhibit angiogenesis - effects that may prove beneficial for several types of cancer. The aim of the present work was to study how Dox affects OS cell growth in vitro and in vivo and OS-driven pulmonary metastasis in vivo.

METHODS

In vitro, the effect of Dox was measured in MG-63 and 143B human OS cell viability, apoptosis, invasion and migration. In vivo, highly metastatic 143B cells were orthotopically implanted into the tibia of SCID mice. The tumour growth and pulmonary metastases between Dox treated and untreated, non-amputated and early amputated xenografts were examined.

RESULTS

In vitro, Dox decreased viability, inhibited invasion, migration, and induced the apoptosis of OS cells. In vivo, Dox significantly enhanced tumour necrosis at primary OS sites, similarly to its in vitro effect, and downregulated the expression of Ki67, MMP2, MMP9, VEGFA and ezrin. It also decreased circulating VEGFA and MMP9 protein levels, in line with the decreased metastatic burden in Dox-treated mice (non-amputated and early-amputated).

CONCLUSIONS

Reprofiling of Dox can prevent the evolvement of pulmonary micro-metastases to clinically detectable macro-metastases and suppress the lethal progress of OS by inhibiting the expression of MMPs, VEGFA and ezrin at primary sites.

Liquid Biopsy-Based Biomarkers of Inflammatory Nociception Identified in Male Rats

Physicians are challenged in treating pain patients due to the lack of quantifiable, objective methods of measuring pain in the clinic; pain sensation is multifaceted and subjective to each individual. There is a critical need for point-of-care quantification of accessible biomarkers to provide objective analyses beyond the subjective pain scales currently employed in clinical care settings. In the present study, we employed an animal model to test the hypothesis that circulating regulators of the inflammatory response directly associate with an objective behavioral response to inflammatory pain. Upon induction of localized paw inflammation, we measured the systemic protein expression of cytokines, and activity levels of matrix metalloproteinases (MMPs) that are known to participate in the inflammatory response at the site of injury and investigated their relationship to the behavioral response across a 24 h period. Intraplantar injection with 1% λ-carrageenan induced a significant increase in paw thickness across this timespan with maximal effects observed at the 8 h timepoint when locomotor activity was also impaired. Expression of the chemokines C-X-C motif chemokine ligand 1 (CXCL1) and C-C motif chemokine ligand 2 (CCL2) positively correlated with paw inflammation and negatively correlated with locomotor activity at 8 h. The ratio of MMP9 to MMP2 activity negatively correlated with paw inflammation at the 8 h timepoint. We postulate that the CXCL1 and CCL2 as well as the ratio of MMP9 to MMP2 activity may serve as predictive biomarkers for the timecourse of inflammation-associated locomotor impairment. These data define opportunities for the future development of a point-of-care device to objectively quantify biomarkers for inflammatory pain states.

Role of Integrin αvβ3 in Doxycycline-Induced Anti-Proliferation in Breast Cancer Cells

Doxycycline, an antibiotic, displays the inhibition of different signal transduction pathways, such as anti-inflammation and anti-proliferation, in different types of cancers. However, the anti-cancer mechanisms of doxycycline via integrin αvβ3 are incompletely understood. Integrin αvβ3 is a cell-surface anchor protein. It is the target for estrogen, androgen, and thyroid hormone and plays a pivotal role in the proliferation, migration, and angiogenic process in cancer cells. In our previous study, thyroxine hormones can interact with integrin αvβ3 to activate the extracellular signal-regulated kinase 1/2 (ERK1/2), and upregulate programmed death-ligand 1 (PD-L1) expression. In the current study, we investigated the inhibitory effects of doxycycline on proliferation in two breast cancer cell lines, MCF-7 and MDA-MB-231 cells. Doxycycline induces concentration-dependent anti-proliferation in both breast cancer cell lines. It regulates gene expressions involved in proliferation, pro-apoptosis, and angiogenesis. Doxycycline suppresses cell cyclin D1 (CCND1) and c-Myc which play crucial roles in proliferation. It also inhibits PD-L1 gene expression. Our findings show that modulation on integrin αvβ3 binding activities changed both thyroxine- and doxycycline-induced signal transductions by an integrin αvβ3 inhibitor (HSDVHK-NH₂). Doxycycline activates phosphorylation of focal adhesion kinase (FAK), a downstream of integrin, but inhibits the ERK1/2 phosphorylation. Regardless, doxycycline-induced FAK phosphorylation is blocked by HSDVHK-NH₂. In addition, the specific mechanism of action associated with pERK1/2 inhibition via integrin αvβ3 is unknown for doxycycline treatment. On the other hand, our findings indicated that inhibiting ERK1/2 activation leads to suppression of PD-L1 expression by doxycycline treatment. Furthermore, doxycycline-induced gene expressions are disturbed by a specific integrin αvβ3 inhibitor (HSDVHK-NH₂) or a mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinases (ERK) kinase (MAPK/ERK, MEK) inhibitor (PD98059). The results imply that doxycycline may interact with integrin αvβ3 and inhibits ERK1/2 activation, thereby regulating cell proliferation and downregulating PD-L1 gene expression in estrogen receptor (ER)-negative breast cancer MDA-MB-231 cells.

A Brief look at antitumor effects of doxycycline in the treatment of colorectal cancer and combination therapies

Colorectal cancer (CRC) is considered the second most frequent cancer globally and one of the deadliest malignancies in humans. On the other hand, over time and facing the challenges of cancer treatment, several therapeutic approaches, including surgery, radiotherapy, chemotherapy, and immunotherapy, are being developed. Evidence showed that combination therapies had given relatively satisfactory clinical outcomes in inhibiting tumor progression and increasing patient survival compared with monotherapy. Among the available compounds and drugs used in chemotherapy, doxycycline, an antimicrobial drug, has been suitable for treating several malignancies such as CRC. It has been revealed that doxycycline has anti-tumor properties and can help control tumor growth in various mechanisms, such as inhibiting anti-apoptotic and angiogenic proteins. In addition, studies have shown that combination therapy with doxycycline and other anti-tumor drugs, such as doxorubicin, anti-angiogenic factors, and anti-check-point blockers, can inhibit tumor progression. Therefore, this review summarized the anti-tumor mechanisms of doxycycline in CRC treatment and related combination therapies.

Doxycycline Ameliorates the Severity of Experimental Proliferative Vitreoretinopathy in Mice

After successful surgeries for patients with rhegmatogenous retinal detachment, the most common cause of retinal redetachment is proliferative vitreoretinopathy (PVR), which causes severe vision impairment and even blindness worldwide. Until now, the major treatment for PVR is surgical removal of the epiretinal membrane, while effective treatment to prevent PVR is still unavailable. Therefore, we investigated the potential of doxycycline, an antibiotic in the tetracycline class, to treat PVR using a mouse model. We used the human retinal pigment epithelial cell line, ARPE-19, for in vitro and in vivo studies to test doxycycline for PVR treatment. We found that doxycycline suppressed the migration, proliferation, and contraction of ARPE-19 cells with reduced p38 MAPK activation and total MMP activity. Intravitreal doxycycline and topical tetracycline treatment significantly ameliorated the PVR severity induced by ARPE-19 cells in mice. PVR increased the expression of MMP-9 and IL-4 and p38 MAPK phosphorylation and modestly decreased IL-10. These effects were reversed by doxycycline and tetracycline treatment in the mouse retina. These results suggest that doxycycline will be a potential treatment for PVR in the future.

Exploring the cytotoxicity and anticancer effects of doxycycline and azithromycin on human glioblastoma multiforme cells

BACKGROUND

Previous studies had reported on the cytotoxic activities of generic antibiotics such as doxycycline (DOXY) and azithromycin (AZI) in multiple types of human cancers. Given that resistance to standard anti-glioblastoma multiforme (GBM) drug [temozolomide (TMZ)] is common and inevitable, alternative candidates are greatly needed.

PURPOSE AND METHOD

The present study was undertaken to explore the cytotoxicity and anticancer effects of DOXY and AZI on human GBM U87 cells via 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT), Hoechst, Annexin V-FITC/PI, and clonogenic assays. CompuSyn software was used to determine the combination index (CI) for DOXY+AZI.

RESULT

Individual treatment with DOXY and AZI decreased U87 cell viability in dose- and time-dependent, and quantitatively comparable to TMZ. Nevertheless, combinations of both antibiotics evidenced antagonistic behaviour in U87 cells. Increased apoptotic event was also observed with the individual treatment of DOXY and AZI. Furthermore, the proliferative and clonogenic capability of 21-day survived U87 cells was completely terminated by DOXY and AZI, but not TMZ.

CONCLUSION

The antiproliferative and apoptosis-inducing activity exhibited by both antibiotics against U87 cells demonstrates their potential as a likely alternative to combat GBM. It would be interesting to find out more about their molecular players and cytotoxic effects in different types of GBM cells, including glioma stem cells (GSCs).

Penicillin disrupts mitochondrial function and induces autophagy in colorectal cancer cell lines

Colorectal cancer is a common malignant tumor of the gastrointestinal tract. Currently, the main treatment is surgical resection, which can be combined with other treatments. However, treatment efficacy is poor, and colorectal cancer is prone to relapse and metastasis; thus, identifying an effective anti-cancer drug is an urgent requirement. The present study examined the antagonistic effect of penicillin on cultured colorectal cancer cells and the related mechanism. A MTT assay was used to assess the growth of the colorectal cancer cells treated with penicillin and to determine the optimal drug concentration. The wound healing and Transwell invasion assays were performed to investigate the effect of penicillin on the migration and invasion of the colorectal cancer cells. Live cell mitochondrial energy metabolism analysis was performed to detect changes in mitochondrial energy metabolism of the colorectal cancer cells, while western blot analysis was used to measure the expression of cytochrome c and autophagy-related protein, LC3. RFP-GFP-LC3 lentivirus was used to detect autophagic flux, and autophagosomes were observed using a transmission electron microscope, while flow cytometry was used to analyze the effect of penicillin on cell cycle progression and apoptosis of the colorectal cancer cells. After penicillin treatment, the growth, migration and invasion ability of the colorectal cancer cells were inhibited. The mitochondrial energy metabolism of the cell was impaired, and the basic respiratory capacity, maximum respiratory capacity, respiratory potential, and ATP production were all reduced. The protein expression levels of the autophagy-related proteins, LC3-II/LC3-I increased in a dose- and time-dependent manner. In addition, autophagy flux and the number of autophagosomes increased, and mitochondrial structural damage was observed. The cell cycle was arrested at the G₁ phase, the number of early apoptotic cells increased and the protein expression level of cleaved caspase-3 increased, while penicillin-induced apoptosis was blocked by the autophagy inhibitor 3-MA. In conclusion, penicillin disrupted mitochondrial function and energy metabolism in the colorectal cancer cells, which resulted in the induction of autophagic apoptosis and ultimately the inhibition of cancer cell growth and metastasis.

The Chemically-Modified Tetracycline COL-3 and Its Parent Compound Doxycycline Prevent Microglial Inflammatory Responses by Reducing Glucose-Mediated Oxidative Stress

We used mouse microglial cells in culture activated by lipopolysaccharide (LPS) or α-synuclein amyloid aggregates (αSa) to study the anti-inflammatory effects of COL-3, a tetracycline derivative without antimicrobial activity. Under LPS or αSa stimulation, COL-3 (10, 20 µM) efficiently repressed the induction of the microglial activation marker protein Iba-1 and the stimulated-release of the pro-inflammatory cytokine TNF-α. COL-3′s inhibitory effects on TNF-α were reproduced by the tetracycline antibiotic doxycycline (DOX; 50 µM), the glucocorticoid dexamethasone, and apocynin (APO), an inhibitor of the superoxide-producing enzyme NADPH oxidase. This last observation suggested that COL-3 and DOX might also operate themselves by restraining oxidative stress-mediated signaling events. Quantitative measurement of intracellular reactive oxygen species (ROS) levels revealed that COL-3 and DOX were indeed as effective as APO in reducing oxidative stress and TNF-α release in activated microglia. ROS inhibition with COL-3 or DOX occurred together with a reduction of microglial glucose accumulation and NADPH synthesis. This suggested that COL-3 and DOX might reduce microglial oxidative burst activity by limiting the glucose-dependent synthesis of NADPH, the requisite substrate for NADPH oxidase. Coherent with this possibility, the glycolysis inhibitor 2-deoxy-D-glucose reproduced the immunosuppressive action of COL-3 and DOX in activated microglia. Overall, we propose that COL-3 and its parent compound DOX exert anti-inflammatory effects in microglial cells by inhibiting glucose-dependent ROS production. These effects might be strengthened by the intrinsic antioxidant properties of DOX and COL-3 in a self-reinforcing manner.

Discovery of 8,9-seco-ent-Kaurane Diterpenoids as Potential Leads for the Treatment of Triple-Negative Breast Cancer

Triple-negative breast cancer (TNBC) is a lethal malignancy without safe and effective therapeutic drugs. In this study, the anti-TNBC bioassay-guided isolation of the medicinal plant Croton kongensis followed by the structural modification led to the construction of a small ent-kaurane diterpenoid library (1-25). With subsequent biological screening, 20 highly potent compounds (IC₅₀s < 3 μM) were identified. Among them, 8,9-seco-ent-kaurane 6 displayed comparable activity (IC₅₀s ∼ 80 nM) to doxorubicin but with better selectivity. The analysis of structure-activity relationships suggested that the cleavage of the C8-C9 bond and the presence of α,β-unsaturated ketone moiety were essential for the activity. The mechanistic study revealed that 6 induced apoptosis, autophagy, and metastasis suppression in TNBC cells via inhibition of Akt. In vivo, 6 significantly suppressed the TNBC tumor growth without causing side effects. All these results suggested that 6 may serve as a promising lead for the development of novel anti-TNBC agents in the future.

Identification of hub genes associated with prognosis, diagnosis, immune infiltration and therapeutic drug in liver cancer by integrated analysis

Background

Liver cancer is one of the most common cancers and causes of cancer death worldwide. The objective was to elucidate novel hub genes which were benefit for diagnosis, prognosis, and targeted therapy in liver cancer via integrated analysis.

Methods

GSE84402, GSE101685, and GSE112791 were filtered from the Gene Expression Omnibus (GEO). Differentially expressed genes (DEGs) were identified by using the GEO2R. The GO and KEGG pathway of DEGs were analyzed in the DAVID. PPI and TF network of the DEGs were constructed by using the STRING, TRANSFAC, and Harmonizome. The relationship between hub genes and prognoses in liver cancer was analyzed in UALCAN based on The Cancer Genome Atlas (TCGA). The diagnostic value of hub genes was evaluated by ROC. The relationship between hub genes and tumor-infiltrate lymphocytes was analyzed in TIMER. The protein levels of hub genes were verified in HPA. The interaction between the hub genes and the drug were identified in DGIdb.

Results

In total, 108 upregulated and 60 downregulated DEGs were enriched in 148 GO terms and 20 KEGG pathways. The mRNA levels and protein levels of CDK1, HMMR, PTTG1, and TTK were higher in liver cancer tissues compared to normal tissues, which showed excellent diagnostic and prognostic value. CDK1, HMMR, PTTG1, and TTK were positively correlated with tumor-infiltrate lymphocytes, which might involve tumor immune response. The CDK1, HMMR, and TTK had close interaction with anticancer agents.

Conclusions

The CDK1, HMMR, PTTG1, and TTK were hub genes in liver cancer; hence, they might be potential biomarkers for diagnosis, prognosis, and targeted therapy of liver cancer.

Effect of chemically modified tetracycline-8 (CMT-8) on hematology, blood chemistry, cytokines and peripheral blood lymphocyte subsets of healthy dogs

Tetracyclines are antibiotics widely used in human and veterinary medicine. Effects on the immune system and inflammatory response, including effects on blood leukocytes proliferation and function and in cytokines synthesis, have been described. Chemically modified tetracyclines (CMT) have lost their antimicrobial activity, but maintain these other properties. This study analyzes the effect of chemically modified tetracycline-8 (CMT-8) on the evolution of complete blood count, blood chemistry, the mRNA expression of selected cytokines and peripheral blood lymphocyte subpopulations distribution in healthy dogs. CMT-8 at a dose of 10 mg/kg once daily was administered per os to six healthy dogs. A control group of five healthy dogs, living in the same conditions than dogs treated with CMT-8, received placebo with an identical therapeutic regimen. When given at the doses used in this study, no side effects of CMT-8 were detected, suggesting a good tolerance and a limited toxicity of the drug. Dogs treated with CMT-8 showed a gradual increase in mean corpuscular hemoglobin. The administration of CMT-8 in healthy dogs did not affect blood mRNA expression of IFN-γ, TNFα, IL-4, IL-6, IL-10, IL-12 p40 and IL-13. However, the lymphocytes expressing class II MHC on their surface decreased during the first two weeks of CMT-8 treatment and subsequently increased for the next three months. Considering the absence of antimicrobial properties of the drug, the effects of CMT-8 detected in this study seem to be unrelated to the classical antimicrobial activity attributed to tetracyclines.

Antibiotics, cancer risk and oncologic treatment efficacy: a practical review of the literature

Antibiotics have been extensively used to treat infectious diseases over the past century and have largely contributed to increased life expectancy over time. However, antibiotic use can impose profound and protracted changes to the diversity of the microbial ecosystem, affecting the composition of up to 30% of the bacterial species in the gut microbiome. By modifying human microbiota composition, antibiotics alter the action of several oncologic drugs, potentially leading to decreased efficacy and increased toxicities. Whether antibiotics interfere with cancer therapies or even increase the risk of cancer development has been under investigation, and no randomised trials have been conducted so far. The aim of the current review is to describe the possible effects of antibiotic therapies on different oncologic treatments, especially immunotherapies, and to explore the link between previous antibiotics use and the development of cancer.

Lipid Phosphate Phosphatases and Cancer

Lipid phosphate phosphatases (LPPs) are a group of three enzymes (LPP1–3) that belong to a phospholipid phosphatase (PLPP) family. The LPPs dephosphorylate a wide spectrum of bioactive lipid phosphates, among which lysophosphatidate (LPA) and sphingosine 1-phosphate (S1P) are two important extracellular signaling molecules. The LPPs are integral membrane proteins, which are localized on plasma membranes and intracellular membranes, including the endoplasmic reticulum and Golgi network. LPPs regulate signaling transduction in cancer cells and demonstrate different effects in cancer progression through the breakdown of extracellular LPA and S1P and other intracellular substrates. This review is intended to summarize an up-to-date understanding about the functions of LPPs in cancers.

The Impact of Matrix Metalloproteinase-9 on the Sequential Steps of the Metastatic Process

In industrialized countries, cancer is the second leading cause of death after cardiovascular disease. Most cancer patients die because of metastases, which consist of the self-transplantation of malignant cells in anatomical sites other than the one from where the tumor arose. Disseminated cancer cells retain the phenotypic features of the primary tumor, and display very poor differentiation indices and functional regulation. Upon arrival at the target organ, they replace preexisting, normal cells, thereby permanently compromising the patient's health; the metastasis can, in turn, metastasize. The spread of cancer cells implies the degradation of the extracellular matrix by a variety of enzymes, among which the matrix metalloproteinase (MMP)-9 is particularly effective. This article reviews the available published literature concerning the important role that MMP-9 has in the metastatic process. Additionally, information is provided on therapeutic approaches aimed at counteracting, or even preventing, the development of metastasis via the use of MMP-9 antagonists.

Understanding Breast cancer: from conventional therapies to repurposed drugs

Breast cancer is the most common cancer among women and is considered a developed country disease. Moreover, is a heterogenous disease, existing different types and stages of breast cancer development, therefore, better understanding of cancer biology, helps to improve the development of therapies. The conventional treatments accessible after diagnosis, have the main goal of controlling the disease, by improving survival. In more advance stages the aim is to prolong life and symptom palliation care. Surgery, radiation therapy and chemotherapy are the main options available, which must be adapted to each person individually. However, patients are developing resistance to the conventional therapies. This resistance is due to alterations in important regulatory pathways such as PI3K/AKt/mTOR, this pathway contributes to trastuzumab resistance, a reference drug to treat breast cancer. Therefore, is proposed the repurposing of drugs, instead of developing drugs de novo, for example, to seek new medical treatments within the drugs available, to be used in breast cancer treatment. Providing safe and tolerable treatments to patients, and new insights to efficacy and efficiency of breast cancer treatments. The economic and social burden of cancer is enormous so it must be taken measures to relieve this burden and to ensure continued access to therapies to all patients. In this review we focus on how conventional therapies against breast cancer are leading to resistance, by reviewing those mechanisms and discussing the efficacy of repurposed drugs to fight breast cancer.

Autotaxin and Breast Cancer: Towards Overcoming Treatment Barriers and Sequelae

After a decade of intense preclinical investigations, the first in-class autotaxin inhibitor, GLPG1690, has entered Phase III clinical trials for idiopathic pulmonary fibrosis. In the intervening time, a deeper understanding of the role of the autotaxin–lysophosphatidate (LPA)–lipid phosphate phosphatase axis in breast cancer progression and treatment resistance has emerged. Concordantly, appreciation of the tumor microenvironment and chronic inflammation in cancer biology has matured. The role of LPA as a central mediator behind these concepts has been exemplified within the breast cancer field. In this review, we will summarize current challenges in breast cancer therapy and delineate how blocking LPA signaling could provide novel adjuvant therapeutic options for overcoming therapy resistance and adverse side effects, including radiation-induced fibrosis. The advent of autotaxin inhibitors in clinical practice could herald their applications as adjuvant therapies to improve the therapeutic indexes of existing treatments for breast and other cancers.

Identification of the targeted therapeutic potential of doxycycline for a subset of gastric cancer patients

The identification of new drugs for the targeted therapy of gastric cancer remains an important need. The RAS/RAF/MEK/ERK/ELK1 signaling cascade is activated in many cancers, including gastric cancer. To identify the targetable inhibitors of the ERK/MAPK pathway, we performed a repurposing screening of a panel of antimicrobial agents in gastric cancer cells using an ERK/MAPK-driven firefly luciferase reporter assay. Multiple antibiotics were identified to inhibit ERK-mediated transcriptional activity. Among them, doxycycline showed high inhibition of ERK/MAPK-regulated transcriptional activity and the levels of ERK proteins. Doxycycline was further identified to inhibit the proliferation and the colony- and spheroid-forming potential of gastric cancer cells. By in vitro signaling pathway and genome-wide expression profiling analyses, doxycycline was identified to inhibit signaling pathways and transcriptional activities regulated by ER, Myc, E2F1, Wnt, SMAD2/3/4, Notch, and OCT4. Doxycycline was also found to activate p53-, ATF6-, NRF1/2-, and MTF1-mediated transcription and inhibit the transcription of histones, proteasomal genes, fibroblast growth factor, and other oncogenic factors. These observations show the multitargeting and targeted therapeutic features of doxycycline for a subset of gastric tumors.

Primary cutaneous CD4-positive small/medium T-cell lymphoproliferative disorder: The first-reported Latin-American case with response to doxycycline

Primary cutaneous CD4+ small/medium T-cell lymphoproliferative disorder is a provisional entity according to the last WHO-EORTC classification. The treatment of choice has not yet been defined. Local therapies have been used with variable response. Doxycycline as a main treatment option is a potential low-cost and effective alternative for this disorder.

Repeated Fractions of X-Radiation to the Breast Fat Pads of Mice Augment Activation of the Autotaxin-Lysophosphatidate-Inflammatory Cycle

Breast cancer patients are usually treated with multiple fractions of radiotherapy (RT) to the whole breast after lumpectomy. We hypothesized that repeated fractions of RT would progressively activate the autotaxin–lysophosphatidate-inflammatory cycle. To test this, a normal breast fat pad and a fat pad containing a mouse 4T1 tumor were irradiated with X-rays using a small-animal “image-guided” RT platform. A single RT dose of 7.5 Gy and three daily doses of 7.5 Gy increased ATX activity and decreased plasma adiponectin concentrations. The concentrations of IL-6 and TNFα in plasma and of VEGF, G-CSF, CCL11 and CXCL10 in the irradiated fat pad were increased, but only after three fractions of RT. In 4T1 breast tumor-bearing mice, three fractions of 7.5 Gy augmented tumor-induced increases in plasma ATX activity and decreased adiponectin levels in the tumor-associated mammary fat pad. There were also increased expressions of multiple inflammatory mediators in the tumor-associated mammary fat pad and in tumors, which was accompanied by increased infiltration of CD45+ leukocytes into tumor-associated adipose tissue. This work provides novel evidence that increased ATX production is an early response to RT and that repeated fractions of RT activate the autotaxin–lysophosphatidate-inflammatory cycle. This wound healing response to RT-induced damage could decrease the efficacy of further fractions of RT.

Oral antibiotic use and risk of colorectal cancer in the United Kingdom, 1989-2012: a matched case-control study

BACKGROUND

Microbiome dysbiosis predisposes to colorectal cancer (CRC), but a population-based study of oral antibiotic exposure and risk patterns is lacking.

OBJECTIVE

To assess the association between oral antibiotic use and CRC risk.

DESIGN

A matched case-control study (incident CRC cases and up to five matched controls) was performed using the Clinical Practice Research Datalink from 1989 to 2012.

RESULTS

28 980 CRC cases and 137 077 controls were identified. Oral antibiotic use was associated with CRC risk, but effects differed by anatomical location. Antibiotic use increased the risk of colon cancer in a dose-dependent fashion (p_trend <0.001). The risk was observed after minimal use, and was greatest in the proximal colon and with antibiotics with anti-anaerobic activity. In contrast, an inverse association was detected between antibiotic use and rectal cancers (p_trend=0.003), particularly with length of antibiotic exposure >60 days (adjusted OR (aOR), 0.85, 95% CI 0.79 to 0.93) as compared with no antibiotic exposure. Penicillins, particularly ampicillin/amoxicillin increased the risk of colon cancer (aOR=1.09 (1.05 to 1.13)), whereas tetracyclines reduced the risk of rectal cancer (aOR=0.90 (0.84 to 0.97)). Significant interactions were detected between antibiotic use and tumour location (colon vs rectum, p_interaction<0.001; proximal colon versus distal colon, p_interaction=0.019). The antibiotic-cancer association was found for antibiotic exposure occurring >10 years before diagnosis (aOR=1.17 (1.06 to 1.31)).

CONCLUSION

Oral antibiotic use is associated with an increased risk of colon cancer but a reduced risk of rectal cancer. This effect heterogeneity may suggest differences in gut microbiota and carcinogenesis mechanisms along the lower intestinal tract.

Inhibition of Autotaxin with GLPG1690 Increases the Efficacy of Radiotherapy and Chemotherapy in a Mouse Model of Breast Cancer

Autotaxin catalyzes the formation of lysophosphatidic acid, which stimulates tumor growth and metastasis and decreases the effectiveness of cancer therapies. In breast cancer, autotaxin is secreted mainly by breast adipocytes, especially when stimulated by inflammatory cytokines produced by tumors. In this work, we studied the effects of an ATX inhibitor, GLPG1690, which is in phase III clinical trials for idiopathic pulmonary fibrosis, on responses to radiotherapy and chemotherapy in a syngeneic orthotopic mouse model of breast cancer. Tumors were treated with fractionated external beam irradiation, which was optimized to decrease tumor weight by approximately 80%. Mice were also dosed twice daily with GLPG1690 or vehicle beginning at 1 day before the radiation until 4 days after radiation was completed. GLPG1690 combined with irradiation did not decrease tumor growth further compared with radiation alone. However, GLPG1690 decreased the uptake of 3'-deoxy-3'-[¹⁸F]-fluorothymidine by tumors and the percentage of Ki67-positive cells. This was also associated with increased cleaved caspase-3 and decreased Bcl-2 levels in these tumors. GLPG1690 decreased irradiation-induced C-C motif chemokine ligand-11 in tumors and levels of IL9, IL12p40, macrophage colony-stimulating factor, and IFNγ in adipose tissue adjacent to the tumor. In other experiments, mice were treated with doxorubicin every 2 days after the tumors developed. GLPG1690 acted synergistically with doxorubicin to decrease tumor growth and the percentage of Ki67-positive cells. GLPG1690 also increased 4-hydroxynonenal-protein adducts in these tumors. These results indicate that inhibiting ATX provides a promising adjuvant to improve the outcomes of radiotherapy and chemotherapy for breast cancer.

A novel specific cleavage of IκBα protein in acute myeloid leukemia cells involves protease PR3

IκBα protein plays an important role in NFκB signaling pathway regulation. The dysfunction of IκBα is tightly related to various diseases, including cancers. However, the molecular mechanisms by which IκBα loses its normal functions are diverse and complex. Here, we reported a novel cleavage of IκBα protein occurred in AML cells. Compared with the full-length IκBα protein, the truncated IκBα fragment exhibited a dramatically weak binding ability to NFκB complex and showed a significant decreased inhibition on NFκB transactivation. Knockdown of PR3, a serine protease mainly expressed in myeloid cells, could inhibit such IκBα cleavage and enhance the sensitivities of AML cells to the differentiation inducers. In addition, we showed that the level of PR3 mRNA was relatively higher in newly diagnosed AML patients than in those patients with complete remission, suggesting that PR3 expression and its involvement in IκBα cleavage might be closely associated with AML. Our studies revealed for the first time a PR3-involved IκBα cleavage in AML cells, providing some new evidences for further understanding the mechanisms underlying the deregulation of NFκB pathway in AML. Finally, we also suggested a potential clinical application value of PR3 protein in the treatment and prognosis surveillance for leukemia.

Increasing the low lipid phosphate phosphatase 1 activity in breast cancer cells decreases transcription by AP-1 and expressions of matrix metalloproteinases and cyclin D1/D3

Metastasis is the leading cause of mortality in breast cancer patients and lysophosphatidate (LPA) signaling promotes this process. LPA signaling is attenuated by lipid phosphate phosphatase-1 (LPP1) whose activity is decreased in cancers. Consequently, increasing LPP1 levels suppresses breast tumor growth and metastasis. This study shows that increasing LPP1 in breast cancer cells decreases transcription through cFos and cJun. This decreases production of cyclin D1/D3 and matrix metalloproteinases (MMPs), which provides new insights into the role of LPP1 in controlling tumor growth and metastasis. Methods: Invasiveness was determined by a Matrigel invasion assay. MMP expression was measured by qPCR, multiplex LASER bead technology and gelatin zymography. Levels of cJUN, cFOS, FRA1, cyclin D1, and cyclin D3 were determined by qPCR and western blotting. Collagen was determined by Picro-Sirius Red staining. Results: Increasing LPP1 expression inhibited invasion of MDA-MB-231 breast cancer cells through Matrigel. This was accompanied by decreases in expression of MMP-1, -3, -7, -9, -10, -12 and -13, which are transcriptionally regulated by the AP-1 complex. Increasing LPP1 attenuated the induction of mRNA of MMP-1, -3, cFOS, and cJUN by EGF or TNFα, but increased FRA1. LPP1 expression also decreased the induction of protein levels for cFOS and cJUN in nuclei and cytoplasmic fractions by EGF and TNFα. Protein levels of cyclin D1 and D3 were also decreased by LPP1. Although FRA1 in total cell lysates or cytoplasm was increased by LPP1, nuclear FRA1 was not affected. LPP1-induced decreases in MMPs in mouse tumors created with MDA-MB-231 cells were accompanied by increased collagen in the tumors and fewer lung metastases. Knockdown of LPP1 in MDA-MB-231 cells increased the protein levels of MMP-1 and -3. Human breast tumors also have lower levels of LPP1 and higher levels of cJUN, cFOS, MMP-1, -7, -8, -9, -12, -13, cyclin D1, and cyclin D3 relative to normal breast tissue. Conclusion: This study demonstrated that the low LPP1 expression in breast cancer cells is associated with high levels of cyclin D1/D3 and MMPs as a result of increased transcription by cFOS and cJUN. Increasing LPP1 expression provides a novel approach for decreasing transcription through AP-1, which could provide a strategy for decreasing tumor growth and metastasis.

Biological Functions and Molecular Mechanisms of Antibiotic Tigecycline in the Treatment of Cancers

As an FDA-approved drug, glycylcycline tigecycline has been used to treat complicated microbial infections. However, recent studies in multiple hematologic and malignant solid tumors reveal that tigecycline treatment induces cell cycle arrest, apoptosis, autophagy and oxidative stress. In addition, tigecycline also inhibits mitochondrial oxidative phosphorylation, cell proliferation, migration, invasion and angiogenesis. Importantly, combinations of tigecycline with chemotherapeutic or targeted drugs such as venetoclax, doxorubicin, vincristine, paclitaxel, cisplatin, and imatinib, have shown to be promising strategies for cancer treatment. Mechanism of action studies reveal that tigecycline leads to the inhibition of mitochondrial translation possibly through interacting with mitochondrial ribosome. Meanwhile, this drug also interferes with several other cell pathways/targets including MYC, HIFs, PI3K/AKT or AMPK-mediated mTOR, cytoplasmic p21 ^CIP1/Waf1, and Wnt/β-catenin signaling. These evidences indicate that antibiotic tigecycline is a promising drug for cancer treatment alone or in combination with other anticancer drugs. This review summarizes the biological function of tigecycline in the treatment of tumors and comprehensively discusses its mode of action.

Lysophospholipases cooperate to mediate lipid homeostasis and lysophospholipid signaling

Lysophospholipids (LysoPLs) are bioactive lipid species involved in cellular signaling processes and the regulation of cell membrane structure. LysoPLs are metabolized through the action of lysophospholipases, including lysophospholipase A1 (LYPLA1) and lysophospholipase A2 (LYPLA2). A new X-ray crystal structure of LYPLA2 compared with a previously published structure of LYPLA1 demonstrated near-identical folding of the two enzymes; however, LYPLA1 and LYPLA2 have displayed distinct substrate specificities in recombinant enzyme assays. To determine how these in vitro substrate preferences translate into a relevant cellular setting and better understand the enzymes' role in LysoPL metabolism, CRISPR-Cas9 technology was utilized to generate stable KOs of Lypla1 and/or Lypla2 in Neuro2a cells. Using these cellular models in combination with a targeted lipidomics approach, LysoPL levels were quantified and compared between cell lines to determine the effect of losing lysophospholipase activity on lipid metabolism. This work suggests that LYPLA1 and LYPLA2 are each able to account for the loss of the other to maintain lipid homeostasis in cells; however, when both are deleted, LysoPL levels are dramatically increased, causing phenotypic and morphological changes to the cells.

Dexamethasone decreases the autotaxin-lysophosphatidate-inflammatory axis in adipose tissue: implications for the metabolic syndrome and breast cancer

Lysophosphatidate (LPA) signaling through 6 receptors is regulated by the balance of LPA production by autotaxin (ATX) vs. LPA degradation by lipid phosphate phosphatases (LPPs). LPA promotes an inflammatory cycle by increasing the synthesis of cyclooxygenase-2 and multiple inflammatory cytokines that stimulate further ATX production. We aimed to determine whether the anti-inflammatory glucocorticoid (GC) dexamethasone (Dex) functions partly by decreasing the ATX-LPA inflammatory cycle in adipose tissue, a major site of ATX secretion. Treatment of human adipose tissue with 10-1000 nM Dex decreased ATX secretion, increased LPP1 expression, and decreased mRNA expressions of IL-6, TNF-α, peroxisome proliferator-activated receptor (PPAR)-γ, and adiponectin. Cotreatment with rosiglitazone (an insulin sensitizer), insulin, or both abolished Dex-induced decreases in ATX and adiponectin secretion, but did not reverse Dex-induced decreases in secretions of 20 inflammatory cytokines and chemokines. Dex-treated mice exhibited lower ATX activity in plasma, brain, and adipose tissue; decreased mRNA levels for LPA and sphingosine 1-phosphate (S1P) receptors in brain; and decreased plasma concentrations of LPA and S1P. Our results establish a novel mechanism for the anti-inflammatory effects of Dex through decreased signaling by the ATX-LPA-inflammatory axis. The GC action in adipose tissue has implications for the pathogenesis of insulin resistance and obesity in metabolic syndrome and breast cancer treatment.-Meng, G., Tang, X., Yang, Z., Zhao, Y., Curtis, J. M., McMullen, T. P. W., Brindley, D. N. Dexamethasone decreases the autotaxin-lysophosphatidate-inflammatory axis in adipose tissue: implications for the metabolic syndrome and breast cancer.

Use of broad-spectrum antibiotics impacts outcome in patients treated with immune checkpoint inhibitors

We carried out a retrospective cohort study on patients with advanced cancer treated with immune checkpoint inhibitors (ICIs) to determine whether antibiotics affect treatment outcome. Sixty consecutive patients were identified, and 17 received systemic antibiotics within 2 weeks before and/or after first dose of ICI. Antibiotic-treated patients were significantly younger (p = 0.0008) and less likely to receive nivolumab (p = 0.08) or had neutrophil:lymphocyte ratio < 5 (p = 0.08). They had a lower response rate (RR) (29.4% vs 62.8%) (p = 0.024) and more inferior progression-free survival (PFS) (p = 0.048). Narrow-spectrum antibiotics did not affect the RR. However, broad-spectrum antibiotics were associated with a lower RR (25% vs 61%) (p = 0.02) and a trend towards longer time to response (median: 14 weeks vs 12 weeks) (p = 0.1). They also had shorter PFS (p = 0.012). Multivariate analysis identified antibiotics as the only factor affecting RR (p = 0.0038) and PFS (p = 0.01). We next examined the 21 patients whose PFS lasted for 12 weeks or more. Five of the 21 patients received broad-spectrum antibiotics within 10 weeks before disease progression. There was a trend towards shorter PFS in these patients (p = 0.1). Finally, antibiotic-treated patients experienced shorter overall survival (OS) (median: 24 months vs 89 months) (p = 0.003). Multivariate analysis found age (p = 0.035) and antibiotics (p = 0.038) to be the only factors affecting OS. Our results point to a detrimental effect of broad-spectrum antibiotics on treatment outcome to ICI therapy.

Coming of Age for Autotaxin and Lysophosphatidate Signaling: Clinical Applications for Preventing, Detecting and Targeting Tumor-Promoting Inflammation

A quarter-century after the discovery of autotaxin in cell culture, the autotaxin-lysophosphatidate (LPA)-lipid phosphate phosphatase axis is now a promising clinical target for treating chronic inflammatory conditions, mitigating fibrosis progression, and improving the efficacy of existing cancer chemotherapies and radiotherapy. Nearly half of the literature on this axis has been published during the last five years. In cancer biology, LPA signaling is increasingly being recognized as a central mediator of the progression of chronic inflammation in the establishment of a tumor microenvironment which promotes cancer growth, immune evasion, metastasis, and treatment resistance. In this review, we will summarize recent advances made in understanding LPA signaling with respect to chronic inflammation and cancer. We will also provide perspectives on the applications of inhibitors of LPA signaling in preventing cancer initiation, as adjuncts extending the efficacy of current cancer treatments by blocking inflammation caused by either the cancer or the cancer therapy itself, and by disruption of the tumor microenvironment. Overall, LPA, a simple molecule that mediates a plethora of biological effects, can be targeted at its levels of production by autotaxin, LPA receptors or through LPA degradation by lipid phosphate phosphatases. Drugs for these applications will soon be entering clinical practice.

Lysophosphatidate Signaling: The Tumor Microenvironment's New Nemesis

Lysophosphatidate (LPA) is emerging as a potent mediator of cancer progression in the tumor microenvironment. Strategies for targeting LPA signaling have recently entered clinical trials for fibrosis. These therapies have potential to improve the efficacies of existing chemotherapies and radiotherapy by attenuating chronic inflammation, irrespective of diverse mutations within cancer cells.