Apoptotic Vesicles: Therapeutic Mechanisms and Critical Issues

Apoptosis is the most prominent mode of programmed cell death and is necessary for the maintenance of tissue homeostasis. During cell apoptosis, a distinctive population of extracellular vesicles is generated, termed apoptotic vesicles (apoVs). ApoVs inherit a variety of biological molecules such as proteins, RNAs, nuclear components, lipids, and gasotransmitters from their parent cells. ApoVs have shown promising therapeutic potential for inflammation, tumors, immune disorders, and tissue regeneration. In addition, apoVs can be used as drug carriers, vaccine development, and disease diagnosis. Recently, apoVs have been used in clinical trials to treat a variety of diseases, such as temporomandibular joint osteoarthritis and the regeneration of functional alveolar bone. Here, we review the history of apoV research, current preclinical and clinical studies, and the potential issues of apoV application.

Ice sheet-free West Antarctica during peak early Oligocene glaciation

One of Earth's most fundamental climate shifts, the greenhouse-icehouse transition 34 million years ago, initiated Antarctic ice sheet buildup, influencing global climate until today. However, the extent of the ice sheet during the Early Oligocene Glacial Maximum (~33.7 to 33.2 million years ago) that immediately followed this transition-a critical knowledge gap for assessing feedbacks between permanently glaciated areas and early Cenozoic global climate reorganization-is uncertain. In this work, we present shallow-marine drilling data constraining earliest Oligocene environmental conditions on West Antarctica's Pacific margin-a key region for understanding Antarctic ice sheet evolution. These data indicate a cool-temperate environment with mild ocean and air temperatures that prevented West Antarctic Ice Sheet formation. Climate-ice sheet modeling corroborates a highly asymmetric Antarctic ice sheet, thereby revealing its differential regional response to past and future climatic change.

CT venography combined with ultrasound-guided minimally invasive treatment for recurrent varicose veins: a pilot paired-design clinical trial

AIM

To compare 1-year outcomes of computed tomography venography (CTV) combined with ultrasound-guided minimally invasive treatment with ascending phlebography and ultrasound-guided treatment for recurrent varicose veins.

MATERIALS AND METHODS

Consecutive patients with unilateral recurrent varicose veins were matched by gender, age, C classification, and degree of obesity, and randomised in a 1:1 ratio to receive either CTV (CTV group) or ascending phlebography (control group) combined with ultrasound-guided minimally invasive treatment. Patients were followed up by clinical and ultrasound examination. Follow-up was scheduled at 1 week, and 3, 6, and 12 months. The primary outcome measure was the Venous Clinical Severity Score (VCSS) at 12 months. Measures of secondary outcome included Chronic Insufficiency Venous International Questionnaire-20 (CIVIQ-20) score, recurrence of varicose vein or ulcer during 12 months, ulcer healing time, detection and location of treated veins.

RESULTS

Eighty patients were enrolled. Median VCSS in the CTV group was lower than it in the control group (p=0.04) and the CIVIQ-20 score was higher than the control group (p=0.02). By 12 months, no symptomatically recurrent varicose veins or ulcers had occurred. The ulcer healing time in CTV group was shorter (p<0.01). A greater number of patients had treated veins detected using CTV than by ascending venography (p=0.01), especially among patients with recurrence reflux veins in the groin, perineum, and vulva (p<0.01).

CONCLUSION

CTV combined with ultrasound may be more helpful than ascending phlebography combined with ultrasound to improve treatment efficacy for recurrent varices. These results should be verified by an future study with more patients and long-term follow-up.

Clinical and radiographic outcomes of a combined surgery approach to treat peri-implantitis

Peri-implant infra-bony defects are difficult to treat, and data on the management of peri-implantitis are lacking. The aim of this study was to evaluate the effect of a combined surgical approach to manage peri-implantitis: implantoplasty with xenogeneic bone grafting and a concentrated growth factor membrane. Two independent examiners analysed the medical records and radiographs taken before surgery and at the last follow-up. Data were analysed at the implant level; some patient-level data (age, sex, smoking habit) were also considered. Linear regression analysis with generalized estimating equations (GEE) was used to explore the effect of variables of interest (including marginal bone level (MBL)) on implantitis treatment success and resolution rates. The effect of the prosthesis type on postoperative clinical and radiographic parameters was also explored by GEE, with adjustment for age, sex, tooth site, location, follow-up duration, and implant length (model IV including all). Thirty patients with 72 implants were investigated. The implant survival rate was 100% over a mean observation period of 3.3 years (range 2-11 years). The treatment success rate (bone loss <0.5 mm, no bleeding on probing (BOP), no suppuration, probing depth (PD) < 5 mm) was higher in females than males (50% vs 19.0%; P = 0.008). At the last postoperative follow-up, the MBL (1.51 ± 1.07 vs 4.01 ± 1.13 mm), PD (3.61 ± 0.84 vs 6.54 ± 1.01 mm), and BOP (23.38 ± 23.18% vs 79.17 ± 15.51%) were significantly reduced when compared to pre-surgery values (all P < 0.001). Furthermore, a significantly higher PD reduction (β = -1.10 mm, 95% confidence interval -1.97 to -0.23 mm, P = 0.014) was observed for implants with a single crown than a full-arch prosthesis (GEE model IV). Preliminary clinical and radiographic data indicate that implantoplasty in combination with surgery could be an effective treatment option for peri-implantitis.

Naples prognostic score as a predictor of outcomes in lung cancer: a systematic review and meta-analysis

OBJECTIVE

The Naples prognostic score (NPS) is a newly developed indicator of inflammation and nutritional status. However, its role in predicting the prognosis of lung cancer is unclear. We hereby reviewed the association between NPS and outcomes of lung cancer.

MATERIALS AND METHODS

PubMed, Web of Science, Embase, and Google Scholar were searched up to 15th April 2023 for studies assessing the predictive role of NPS for overall survival (OS) and disease-free survival (DFS) in lung cancer.

RESULTS

Seven studies were included. All were from China. One study was on small cell lung cancer, while the rest were on non-small cell lung cancer. Meta-analysis demonstrated that a high NPS score was a significant predictor of OS (HR: 3.21 95% CI: 2.27, 4.54 I2=62%) and disease-free survival (DFS) (HR: 3.81 95% CI: 2.57, 5.64 I2=65%) in lung cancer patients. Subgroup analysis based on different NPS reference values also showed similar results. The results remained significant on sensitivity analysis.

CONCLUSIONS

The NPS is a strong and independent prognostic indicator of lung cancer patients. Higher NPS scores are associated with worse OS and DFS. Further studies from non-Chinese populations are needed to supplement the results.

[The performance of digital chest radiographs in the detection and diagnosis of pulmonary nodules and the consistency among readers]

Objective: To investigate the detection and diagnostic efficacy of chest radiographs for ≤30 mm pulmonary nodules and the factors affecting them, and to compare the level of consistency among readers. Methods: A total of 43 patients with asymptomatic pulmonary nodules who consulted in Cancer Hospital, Chinese Academy of Medical Sciences from 2012 to 2014 and had chest CT and X-ray chest radiographs during the same period were retrospectively selected, and one nodule ≤30 mm was visible on chest CT images in the whole group (total 43 nodules in the whole group). One senior radiologist with more than 20 years of experience in imaging diagnosis reviewed CT images and recording the size, morphology, location, and density of nodules was selected retrospectively. Six radiologists with different levels of experience (2 residents, 2 attending physicians and 2 associate chief physicians independently reviewed the chest images and recorded the time of review, nodule detection, and diagnostic opinion. The CT imaging characteristics of detected and undetected nodules on X images were compared, and the factors affecting the detection of nodules on X-ray images were analyzed. Detection sensitivity and diagnosis accuracy rate of 6 radiologists were calculated, and the level of consistency among them was compared to analyze the influence of radiologists' seniority and reading time on the diagnosis results. Results: The number of nodules detected by all 6 radiologists was 17, with a sensitivity of detection of 39.5%(17/43). The number of nodules detected by ≥5, ≥4, ≥3, ≥2, and ≥1 physicians was 20, 21, 23, 25, and 28 nodules, respectively, with detection sensitivities of 46.5%, 48.8%, 53.5%, 58.1%, and 65.1%, respectively. Reasons for false-negative result of detection on X-ray images included the size, location, density, and morphology of the nodule. The sensitivity of detecting ≤30 mm, ≤20 mm, ≤15 mm, and ≤10 mm nodules was 46.5%-58.1%, 45.9%-54.1%, 36.0%-44.0%, and 36.4% for the 6 radiologists, respectively; the diagnosis accuracy rate was 19.0%-85.0%, 16.7%-6.5%, 18.2%-80.0%, and 0%-75.0%, respectively. The consistency of nodule detection among 6 doctors was good (Kappa value: 0.629-0.907) and the consistency of diagnostic results among them was moderate or poor (Kappa value: 0.350-0.653). The higher the radiologist's seniority, the shorter the time required to read the images. The reading time and the seniority of the radiologists had no significant influence on the detection and diagnosis results (P>0.05). Conclusions: The ability of radiographs to detect lung nodules ≤30 mm is limited, and the ability to determine the nature of the nodules is not sufficient, and the increase in reading time and seniority of the radiologists will not improve the diagnostic accuracy. X-ray film exam alone is not suitable for lung cancer diagnosis.

[Prevalence and risk factors of deep venous thrombosis of lower extremity in patients with stage and pressure ulcers on admission]

Objective: To investigate the incidence and risk factors of deep venous thrombosis (DVT) of lower extremity in patients with stage Ⅲ and Ⅳ pressure ulcer on admission. Methods: A retrospective case series study was conducted. A total of 241 patients with stage Ⅲ and Ⅳ pressure ulcers who met the inclusion criteria and were discharged from the Department of Wound Repair of the First People's Hospital of Zhengzhou from January 1, 2015 to December 31, 2019 were enrolled in this study, including 134 males and 107 females, aged 22 to 93 years, with a median age of 68 years; 37 patients were with stage Ⅲ pressure ulcers and 204 patients were with stage Ⅳ pressure ulcers. The DVT occurrence of patients was recorded. According to whether DVT of lower extremity veins was diagnosed by color Doppler ultrasound within 48 h after admission or not, the patients were divided into DVT group (n=37) and non-DVT group (n=204). Data of patients in the two groups were collected and compared, including gender, age, duration of pressure ulcer, time in bed, and combination with diabetes, hypertension, coronary heart disease, cerebral infarction, pneumonia, sepsis/septic shock, and paraplegia, and the plasma D-dimer level and Caprini score within 24 h after admission. Data were statistically analyzed with independent sample t test, Mann-Whitney U test, chi-square test, and Fisher's exact probability test. The indicators with statistically significant differences between the two groups were analyzed with multivariate logistic regression analysis to screen the independent risk factors influencing the DVT of lower extremity in 241 patients with stage Ⅲ and Ⅳ pressure ulcers on admission. Results: The incidence of DVT of lower extremity was 15.4% (37/241), of which 86.5% (32/37) were asymptomatic DVT. Among the DVT of 46 lower limbs, only 29 involved the inferior genicular veins, accounting for 63.0%. There were no statistically significant differences in gender, duration of pressure ulcer, combination with diabetes, hypertension, coronary heart disease, cerebral infarction, pneumonia, and sepsis/septic shock of patients between the two groups (P>0.05), while there were statistically significant differences in age, time in bed, combination with paraplegia, the plasma D-dimer level and Caprini score of patients between the two groups(t=-3.19, Z=-2.04, χ2=4.44, Z=-3.89, t=-2.14, respectively, P<0.05 or P<0.01). Multivariate logistic regression analysis showed that age and plasma D-dimer level were independent risk factors influencing the DVT of lower extremity in 241 patients with stage Ⅲ and Ⅳ pressure ulcers on admission (with odds ratios of 1.03 and 1.18, respectively, with 95% confidence intervals of 1.00-1.06 and 1.05-1.33, respectively, P<0.05 or P<0.01). Conclusions: The patients with stage Ⅲ and Ⅳ pressure ulcers have a higher incidence of DVT on admission, with age and plasma D-dimer level being the independent risk factors for DVT of lower extremity. It is necessary to pay attention to the targeted screening of DVT and education of its prevention.

Identification of the metabolic signatures of prostate cancer by mass spectrometry-based plasma and urine metabolomics analysis

OBJECTIVE

Prostate cancer (PCa) is one of the most commonly diagnosed cancers among men which is associated with profound metabolic changes. Systematic analysis of the metabolic alterations and identification of new biomarkers may benefit PCa diagnosis and a deep understanding of the pathological mechanism. The purpose of this study was to determine the metabolic features of PCa.

METHODS

Plasma and urine metabolites from 89 prostate cancer (PCa) patients, 84 benign prostatic hyperplasia (BPH) patients, and 70 healthy males were analyzed using LC-MS/MS and GC-MS. The Orthogonalised Partial Least Squares Discriminant Analysis (OPLS-DA) was used to find the significantly changed metabolites. The clinical value of the candidate markers was examined by receiver operating characteristic curve analysis and compared with prostate-specific antigen (PSA).

RESULTS

Multivariate statistical analyses found a series of altered metabolites, which related to the urea cycle, tricarboxylic acid cycle (TCA), fatty acid metabolism, and the glycine cleavage system. Plasma Glu/Gln showed the highest predictive value (AUC = 0.984) when differentiating PCa patients from healthy controls, with a higher sensitivity than PSA (96.6% vs. 94.4%). Both Glu/Gln and PSA displayed a low specificity when differentiating PCa patients from BPH patients (<53.2%), while the combination of Glu/Gln and PSA can further increase the diagnostic specificity to 66.9%.

CONCLUSIONS

The present study showed the metabolic features of PCa, provided strong evidence that the amide nitrogen and the energy metabolic pathways could be a valuable source of markers for PCa. Several candidate markers identified in this study were clinically valuable for further assessment.

Long noncoding RNA MGC27382 inhibits proliferation and metastasis of non-small cell lung cancer cells via down-regulating AKT/GSK3β pathway

PURPOSE

Persistent abnormal proliferation and long distant metastasis of tumors contribute to high mortality rate in non-small cell lung cancer (NSCLC) patients. Strategies that prevent NSCLC proliferation and/or metastasis have been studied but still need to be further explored. Numerous studies have proved the diversity functions of long noncoding RNAs (lncRNAs) exerted in cancer, including NSCLC. In this study, we aim to identify and investigate the role of novel lncRNAs in NSCLC progression.

METHODS

RNA sequence data were retrieved from the Cancer Genome Atlas (TCGA), differentially expressed lncRNAs (DElncRNAs) were screened out based on the R language, then real-time PCR experiment was introduced to detect the DElncRNA expression levels. A series of experiments including MTT, cell cycle, transwell, and wound healing assays were employed to explore the effect of DElncRNA MGC27382 on cell proliferation and invasion ability.

RESULTS

We detected that DElncRNA MGC27382 is down-regulated in NSCLC tissues and cells. Overexpression of MGC27382 prevented NSCLC cell proliferation via down-regulating cyclin D1 and cyclin E. Moreover, wound healing and transwell assays indicated that the ability of cell invasion and migration could be impaired when cells were treated with MGC27382 overexpression. Further studies demonstrated that MGC27382-mediated inhibition on NSCLC progression can be impaired by LY294002, which is a frequently used inhibitor of AKT/GSK3β pathway.

CONCLUSION

MGC27382 is down-regulated in NSCLC. It exerts an inhibitory role in NSCLC development through suppressing the AKT/GSK3β pathway. Our results indicate that the lncRNA MGC27382 might be a tumor-suppressor gene in NSCLC. Overexpression of MGC27382 is thought to be a potential strategy for overcoming NSCLC progression.

Total cholesterol affects the outcome of patients with anterior cerebral artery-occluded acute ischemic stroke treated with thrombolysis

OBJECTIVE

In this study, we investigated whether certain types of lipid profiles are major contributors of acute ischemic stroke (AIS).

PATIENTS AND METHODS

We screened 13,285 hospitalized patients in two stroke medical centers treated with thrombolysis, thrombectomy, or conventional care for anterior cerebral artery-occluded AIS, and found 266 patients. We examined their plasma lipid profiles using the cutoff values from a receiver operating characteristic (ROC) curve. We applied a multivariate logistic regression or Fisher's exact test to compare their outcomes and risk factors. We used the modified Rankin scale (mRS) score to assess the major clinical outcome of the patients 3 months after disease onset. Mortality and symptomatic intracranial hemorrhage (sICH) were both evaluated as risk factors. We analyzed symptoms' improvements at discharge as a disease outcome measure.

RESULTS

In the patients with anterior cerebral artery-occluded AIS (NIHSS ≥ 10) treated by intravenous (IV) thrombolysis, a total cholesterol (TC) level greater than 5.07 mmol/L predicted a poor outcome (OR 3.55, 95% CI 1.21,10.46, p=0.021).

CONCLUSIONS

In patients with anterior cerebral artery-occluded AIS, the TC level is a promising prognosis marker for the IV thrombolysis outcome.

Baicalin ameliorates Mycoplasma gallisepticum-induced lung inflammation in chicken by inhibiting TLR6-mediated NF-κB signalling

1. Mycoplasma gallisepticum (MG) causes severe lung inflammation and cell damage by activating toll-like receptor (TLR) signalling, the nuclear factor-kappaB (NF-κB) pathway and pro-inflammatory cytokine gene expression. Baicalin (BA) is a flavonoid extracted from Scutellaria baicalensis, which possesses anti-inflammatory and anti-bacterial properties. This study investigated the effect of BA in MG-induced lung inflammation and its potential mechanism in MG-infected chicken embryo lungs and DF-1 cells.2. The histopathological examination result showed that BA treatment alleviated MG-induced lung pathological changes. In addition, CCK-8 and cell cycle assays showed that BA treatment inhibited MG-induced cell proliferation and cell cycle progression in DF-1 cells.3. The ELISA and RT-qPCR results demonstrated that BA treatment decreased the expression of interleukin-1beta (IL-1β), IL-6, and tumour necrosis factor-alpha (TNF-α) both in MG-infected chicken embryo lungs and DF-1 cells.4. The results revealed that BA inhibited mRNA expression levels of toll-like receptor-6 (TLR6), myeloid differentiation primary response gene-88 (MyD88) and nuclear factor-κB (NF-κB), and the nuclear translocation of NF-κB-p655. In conclusion, the results showed that BA has a protective effect against MG-induced lung inflammation in chicken by inhibiting the TLR6-mediated NF-κB signalling.

Observation of the efficacy of naloxone combined with acyclovir in the treatment of children viral encephalitis and its impacts on IL-1 and IL-6

OBJECTIVE

To analyze the clinical efficacy of naloxone combined with acyclovir in the treatment of children viral encephalitis and the impacts on inflammatory factors IL-1 and IL-6.

PATIENTS AND METHODS

96 children with viral encephalitis were retrospectively analyzed. They were treated from July 2013 to January 2014 in our hospital. They were divided into control group (45 cases treated with acyclovir) and observation group (51 cases treated with acyclovir combined with naloxone). Both groups were treated with comprehensive measures. Changes of the content of serum IL-1 and IL-6 in the two groups before and after treatment were monitored by enzyme-linked immunosorbent assay (ELISA). Signs, recovery time of clinical symptoms, total effective rate, occurrence of adverse reactions and adverse reactions after treatment of children in the two groups were compared.

RESULTS

Levels of serum IL-1 and IL-6 of children in the control group and the observation group decreased after treatment, and the decrease was greater in the observation group (p<0.05). Signs and recovery time of clinical symptoms of the observation group were significantly shorter than that of the control group (p<0.05). Indexes of serum in the observation group were significantly lower than those of the control group after treatment (p<0.05). The total effective rate of the observation group was significantly higher than that of the control group (p<0.05). The prevalence of adverse reactions and sequelae in the observation group were lower than those in the control group (p<0.05).

CONCLUSIONS

In the treatment of children, viral encephalitis has naloxone combined with ganciclovir had a more significant effect on the decrease of levels of serum IL-1 and IL-6; naloxone combined with acyclovir in the treatment of children viral encephalitis had better effects, lower adverse reactions and lower prevalence of sequelae compared with sole medication, which is worth clinical promotion.

Long noncoding RNA HOTAIR regulates the invasion and metastasis of prostate cancer by targeting hepaCAM

Background

The role of HOX transcript antisense RNA (HOTAIR) has been proven to be important in tumorigenesis. However, how this molecule promotes metastasis and invasion in PCa is still unclear.

Methods

The relationship between HOTAIR and hepatocellular adhesion molecule (hepaCAM) in PCa was identified by immunohistochemistry, immunofluorescence, plasmid transfection, quantitative real-time PCR and immunoblotting. The regulatory effects of HOTAIR on hepaCAM and MAPK signalling and their key roles in PCa metastasis were investigated in vitro.

Results

The expression of HOTAIR was inversely correlated with hepaCAM in the blood and tissue of PCa patients. Here, hepaCAM was identified as a novel target gene of HOTAIR and was critical for the invasiveness of PCa. HOTAIR recruited PRC2 to the hepaCAM promoter, resulting in high levels of H3K27me3 and the absence of hepaCAM with an abnormally activated MAPK pathway. Both HOTAIR depletion and EZH2 inhibition could induce hepaCAM re-expression with inhibitory MAPK signalling and decrease the invasive and metastatic capabilities of PCa cells.

Conclusions

This study demonstrates that HOTAIR promotes invasion and metastasis of PCa by decreasing the inhibitory effect of hepaCAM on MAPK signalling. Therefore, the HOTAIR/hepaCAM/MAPK axis may provide a new avenue towards therapeutic strategies and prognostic indicators for advanced prostate cancer.

Elastohydrodynamic Scaling Law for Heart Rates

Animal hearts are soft shells that actively pump blood to oxygenate tissues. Here, we propose an allometric scaling law for the heart rate based on the idea of elastohydrodynamic resonance of a fluid-loaded soft active elastic shell that buckles and contracts axially when twisted periodically. We show that this picture is consistent with numerical simulations of soft cylindrical shells that twist-buckle while pumping a viscous fluid, yielding optimum ejection fractions of 35%-40% when driven resonantly. Our scaling law is consistent with experimental measurements of heart rates over 2 orders of magnitude, and provides a mechanistic basis for how metabolism scales with organism size. In addition to providing a physical rationale for the heart rate and metabolism of an organism, our results suggest a simple design principle for soft fluidic pumps.

Characterization of co-culture of Aeromonas and Pseudomonas bacterial biofilm and spoilage potential on refrigerated grass carp (Ctenopharyngodon idellus)

Aeromonas and Pseudomonas are important bacterial species involved in spoilage of refrigerated freshwater fish. In this study, 10 Aeromonas and seven Pseudomonas bacterial strains were isolated from spoiled grass carp and identified. Twelve of seventeen bacterial strains showed high potential of biofilm formation and 14 of 17 can produce extracellular protease. In order to explore the spoilage capacity of dual-species, the sterile grass carp fillets were inoculated with mono- and dual-species of Aeromonas salmonicida and Pseudomonas azotoformans strains. The results revealed significantly higher levels of the total viable count and total volatile basic nitrogen in dual-species as compared to mono-species from day 6. The higher contents of histamine, cadaverine and serious degradation in muscles tissue were also observed in dual-species after 10 days of storage. Results of in vitro experiments showed that the co-culture of A. salmonicida and P. azotoformans significantly increased the bacterial maximum growth rate, promoted the biofilm formation and improved the spoilage capacity of bacterial strains. This study has revealed that the co-culture of Aeromonas and Pseudomonas bacterial strains accelerated spoilage process of grass carp and increased biofilm formation. It indicates that the mixed-cultures of spoilage micro-organisms pose a huge threat to food industry.

PLCε regulates metabolism and metastasis signaling via HIF-1α/MEK/ERK pathway in prostate cancer

Phospholipase C-ε (PLCε) is frequently overexpressed in tumors and plays an important role in the regulation of tumorigenesis. Although great progress has been made in understanding biological roles of PLCε, the relevant molecular mechanisms underlying its pro-tumor activity remain largely unclear. Here, we demonstrated that PLCε knockdown reduced cell metastasis, glucose consumption and lactate production in a manner that depended on hypoxia inducible factor 1α (HIF-1α) expression in prostate cancer cells. Interestingly, our findings showed that the expression levels of PLCε were positively associated with those of HIF-1α in clinical prostate carcinoma samples. Knockdown of PLCε impaired HIF-1α levels and transcriptional activity by regulating the extracellular-signal-regulated kinase pathway, and blocking HIF-1α nuclear translocation. Furthermore, PLCε could interact with the von Hippel-Lindau E3 ligase complex to modulate the stability of HIF-1α. Collectively, our findings demonstrate that PLCε could be a crucial positive regulator of HIF-1α, which would promote PLCε-enhanced tumorigenesis.

PLCε knockdown overcomes drug resistance to androgen receptor antagonist in castration-resistant prostate cancer by suppressing the wnt3a/β-catenin pathway

Most prostate cancers (Pcas) develop into castration-resistant prostate cancer (CRPC) after receiving androgen deprivation therapy (ADT). The expression levels of PLCε and wnt3a are increased in Pca and regulate androgen receptor (AR) activity. However, the biological function and mechanisms of PLCε and wnt3a in CRPC remain unknown. In this study, we found that the expression levels of PLCε, wnt3a, and AR were significantly increased in CRPC tissues as well as bicalutamide-resistant-LNCaP and enzalutamide-resistant-LNCaP cells. In addition, PLCε knockdown partly restored the sensitivity of drug-resistant cells to bicalutamide and enzalutamide by inhibiting the activity of the wnt3a/β-catenin/AR signaling axis. Interestingly, the resistance of LNCaP cells docetaxel is related to PLCε but not the wnt3a/β-catenin pathway. We also found that the combination of PLCε knockdown and enzalutamide treatment synergistically suppressed cell proliferation, tumor growth, and bone metastasis using in vitro and in vivo experiments. Our study revealed that PLCε is involved in the progression of drug-resistance in CRPC and could be a new target for the treatment of CRPC.

Phospholipase C (PLC)ε Promotes Androgen Receptor Antagonist Resistance via the Bone Morphogenetic Protein (BMP)-6/SMAD Axis in a Castration-Resistant Prostate Cancer Cell Line

Background

Primary therapy for patients with advanced prostate cancer (PCa) consists of androgen deprivation therapy targeting the androgen receptor (AR) axis. However, most tumors progress to castration-resistant prostate cancer (CRPC) within 18–24 months. The purpose of the present study was to investigate the mechanisms through which PCa acquires drug resistance after long-term treatment with AR antagonists.

Material/Methods

Online database analysis and bioinformatics analysis were performed to identify signaling activated during anti-androgen treatment. MTT assay was used to detect cell viability. RT-qPCR was performed to examine the mRNA expression of the indicated genes. Colony formation assay was performed to observe cell proliferation. Transwell assay was conducted to demonstrate invasive ability. Protein levels were determined by Western blot analysis and immunofluorescence assays.

Results

An online database search and bioinformatics analysis indicated that bone morphogenetic protein (BMP)-6/SMAD signaling was activated in enzalutamide-resistant LNCaP cells. Furthermore, this signaling interaction was experimentally verified in bicalutamide- and enzalutamide-resistant LNCaP cells, which may be regulated by phospholipase C (PLC)ɛ and induced cell proliferation and invasion. Of note, a positive correlation was observed between PLCɛ and BMP-6 in CRPC tissue samples, which may promote bone metastasis and suggests a poor prognosis.

Conclusions

The present results suggest that targeting of PLCɛ/BMP-6/SMAD signaling may increase the sensitivity of CRPC to AR antagonists and inhibit tumor progression.