PMS2 amplification contributes brain metastasis from lung cancer.

BACKGROUND: Lung adenocarcinoma metastasizing to the brain results in a notable increase in patient mortality. The high incidence and its impact on survival presents a critical unmet need to develop an improved understanding of its mechanisms. METHODS: To identify genes that drive brain metastasis of tumor cells, we collected cerebrospinal fluid samples and paired plasma samples from 114 lung adenocarcinoma patients with brain metastasis and performed 168 panel-targeted gene sequencing. We examined the biological behavior of PMS2 (PMS1 Homolog 2)-amplified lung cancer cell lines through wound healing assays and migration assays. In vivo imaging techniques are used to detect fluorescent signals that colonize the mouse brain. RNA sequencing was used to compare differentially expressed genes between PMS2 amplification and wild-type lung cancer cell lines. RESULTS: We discovered that PMS2 amplification was a plausible candidate driver of brain metastasis. Via in vivo and in vitro assays, we validated that PMS2 amplified PC-9 and LLC lung cancer cells had strong migration and invasion capabilities. The functional pathway of PMS2 amplification of lung cancer cells is mainly enriched in thiamine, butanoate, glutathione metabolism. CONCLUSION: Tumor cells elevated expression of PMS2 possess the capacity to augment the metastatic potential of lung cancer and establish colonies within the brain through metabolism pathways.

Different genetic profiles contribute to worse overall survival in patients with leptomeningeal metastases of non-small-cell lung cancer.

BACKGROUND: To assess the genetic characteristics of central nervous system (CNS) metastases from non-small-cell lung cancer (NSCLC), we gathered the genetic profiles of brain metastases (BM) and leptomeningeal metastases (LM). Our objective was to identify genetic factors contributing to poorer overall survival (OS) in NSCLC patients with LM. METHODS: This study included 25 consecutive patients with BM and 52 patients with LM from Guangdong Sanjiu Brain Hospital. All participants underwent 168-target panel sequencing. RESULTS: Among the 25 patients with BM, TP53 was the most frequently mutated gene (44%), followed by driver genes such as EGFR and BRAF (40% and 20%, respectively). In patients with BM, EGFR_amp and CDK4 were also frequently mutated, with rates of 20% and 16%, respectively. The genetic landscape of patients with LM differed, with the top mutated genes being EGFR, TP53, EGFR_amp, CDKN2A, CCNE1, CDK4, PMS2, and PIK3CA, with mutation rates of 77%, 69%, 31%, 29%, 13%, 13%, 13%, and 12%, respectively. In our study, patients with LM exhibited significantly worse OS compared to those with BM (p = 0.029). The mutation rates of TP53, EGFR_amp, and CDKN2A varied between patients with LM and those with BM, at 69.23% vs. 44%, 30.77% vs. 20%, and 28.85% vs. 12%, respectively. Further exploration revealed that patients with BM with TP53 mutations had a shorter OS than patients without TP53 mutations (p = 0.014). Similarly, patients with LM and TP53 mutations presented with worse OS than those without TP53 mutations (p = 0.0067). LM patients with CDKN2A deletions had worse OS than those without CDKN2A deletions (p = 0.037). Additionally, patients with EGFR_amp had a shorter OS than those without EGFR_amp (p = 0.044). CONCLUSIONS: Patients with LM exhibited significantly worse OS than those with BM. Gene signatures, such as TP53, EGFR_amp, and CDKN2A, may account for shorter outcomes in patients with LM.

Uncovering a novel DNA repair-related radiosensitivity model for evaluation of radiotherapy susceptibility in uterine corpus endometrial cancer.

Background: Uterine corpus endometrial cancer (UCEC) exhibit heterogeneity in their DNA repair capacity, which can impact their response to radiotherapy. Our study aimed to identify potential DNA repair-related biomarkers for predicting radiation response in UCEC. Methods: We conducted a thorough analysis of 497 UCEC samples obtained from TCGA database. Using LASSO-COX regression analysis, we constructed a radiosensitivity signature and subsequently divided patients into the radiosensitive (RS) and the radioresistant (RR) groups based on their radiosensitivity index. The GSVA and GSEA were performed to explore functional annotations. The CIBERSORT and ESTIMATE algorithms were utilized to investigate the immune infiltration status of the two groups. Additionally, we utilized the Tumor Immune Dysfunction and Exclusion (TIDE), Immunophenotype Score (IPS), and pRRophetic algorithms to predict the effectiveness of different treatment modalities. Results: We constructed a radiosensitivity index consists of four DNA repair-related genes. Patients in the RS group demonstrated significantly improved prognosis compared to patients in the RR group when treated with radiotherapy. We observed that the RS group exhibited a higher proportion of the POLE ultra-mutated subtype, while the RR group had a higher proportion of the copy number high subtype. GSVA enrichment analysis revealed that the RS group exhibited enrichment in DNA damage repair pathways. Notably, the RS group demonstrated a higher proportion of naïve B cells and follicular helper T cells, while regulatory T cells (Tregs) and memory B cells were more abundant in the RR group. Furthermore, patients in the RS-PD-L1-high subgroup exhibited enrichment in immune-related pathways and increased sensitivity to immunotherapy, which is likely to contribute to their improved prognosis. Additionally, we conducted in vitro experiments to validate the expression of radiosensitivity genes in non-radioresistant (AN3CA) and radioresistant (AN3CA/IR) endometrial cancer cells. Conclusions: In conclusion, our research successfully constructed a radiosensitivity signature with robust predictive capacity. These findings shed light on the association between immune activation, PD-L1 expression, and the response to immunotherapy in the context of radiotherapy.

Mutational signatures of synchronous and metachronous brain metastases from lung adenocarcinoma.

Brain metastasis (BM) is an important cause of mortality for cancer patients. Many patients were diagnosed with brain metastases at their first visit who have not received any treatment while a subset of patients did not have distant metastases at the first visit and brain metastases were detected during the course of systemic therapies. The difference in their genomic characterization is unclear. 96 lung adenocarcinoma patients were enrolled in our study. 53 patients (55%) had synchronous metastatic brain tumors. 43 (45%) patients had metachronous brain metastases. We performed 168 panel-targeted gene sequencing cerebrospinal fluid (CSF) and plasma samples from patients to identify genomic features of synchronous brain metastases (SBM) and metachronous brain metastases (MBM). In conclusion, CSF liquid biopsies have a priority in detecting gene alteration. A comprehensive comparison of molecular profiling between SBM and MBM revealed the most frequently altered genes in both groups were EGFR and TP53, but with different exon point mutations. RTK-RAS and TP53 pathways were the most affected pathways.

Different biopsy techniques for different pancreas graft locations after homolateral simultaneous pancreas-kidney transplantation.

Background: Biopsy of a transplanted pancreas is sometimes necessary in patients who have undergone simultaneous pancreas-kidney (SPK) transplantation and have elevated serum lipase and amylase concentrations. However, the risks associated with pancreatic graft biopsy are high, and the best biopsy technique for different location of pancreatic graft remains unclear. Methods: Depending on the anatomical location of the transplanted pancreas, percutaneous computed tomography (CT) combined with color Doppler-guided puncture biopsy or laparoscopic biopsy was used to obtain samples of transplanted pancreatic tissue that were shallow and deep, respectively. Results: After SPK transplantation, 4 patients developed abnormal serum lipase and amylase concentrations and underwent pancreas graft biopsy, 1 patient underwent percutaneous CT combined with color Doppler-guided puncture biopsy, 2 patients underwent laparoscopic wedge biopsy, and 1 patient underwent laparoscopic and puncture biopsy. All biopsies were performed successfully, with no intra- or postoperative complications (e.g., bleeding, pancreatic leakage, intestinal leakage). Biopsy sampling was effective in 3 patients, including 1 case of acute pancreatic rejection, 1 case of pancreatitis, and 1 case of pancreatic plasmablastic lymphoma. Biopsy failed to retrieve samples in 1 patient with a deep pancreatic graft who underwent laparoscopic wedge biopsy. Conclusions: Pancreas graft biopsy is safe and feasible after SPK transplantation. In addition to the two biopsy methods mentioned, other methods can also be used. Different biopsy strategies should be formulated according to the anatomical location of the transplanted pancreas.

EGFR amplification is a putative resistance mechanism for NSCLC-LM patients with TKI therapy and is associated with poor outcome.

Background: Leptomeningeal metastases (LM) have become increasingly common in non-small cell lung cancer (NSCLC) patients who harbor epidermal growth factor receptor (EGFR) mutation treated with EGFR-TKI and are correlated with inferior prognosis. Evidence in prior research demonstrated that EGFR amplification was more likely presented in advanced clinical stages and was associated with worse survival. However, whether EGFR amplification is a prognostic marker in NSCLC-LM is still inconclusive. Methods: This study enrolled patients diagnosed with NSCLC-LM from June 2019 to September 2021 and who had received previous EGFR-TKI at Guangdong Sanjiu Brain Hospital. Cerebrospinal fluid (CSF) samples were collected and subjected to targeted next-generation sequencing of 168 cancer-related genes. Clinical characteristics and overall survival (OS) were compared in patients with and without EGFR amplification. Results: This study enrolled 53 NSCLC-LM patients, all of whom had EGFR mutations. TP53 and EGFR amplifications are the two most frequent mutations in the study cohort, presenting at 72% (38 of 53) and 40% (21 of 53), respectively. The rate of EGFR amplification was much higher at the time of leptomeningeal progression than at initial diagnosis (p < 0.01). Karnoskfy performance status was poorer (p = 0.021), and CSF pressure was higher (p = 0.0067) in patients with EGFR amplification than those without. A multivariable Cox proportional hazard regression model showed that EGFR amplification was an independent prognostic factor for poorer OS (8.3 vs. 15 months; p = 0.017). The median OS was shorter in NSCLC-LM patients with mutated TP53 than those with wild-type TP53, but the difference was not statistically significant (10 vs. 17.3 months, p = 0.184). Conclusions: EGFR gene amplification could be a potential resistance mechanism to EGFR-TKI failure in NSCLC-LM and is associated with inferior clinical outcomes.

Metabolic characterization of amniotic fluid of fetuses with isolated choroid plexus cyst.

OBJECTIVES: To investigate the amino acid (AA)-related metabolic characteristics of amniotic fluid (AF) obtained by ultrasound-guided amniocentesis from fetuses with isolated choroid plexus cysts of the central nervous system. METHODS: Ultrasound-guided amniocentesis was performed on 17 fetuses with isolated choroid plexus cysts (ICPCs) and 17 normal fetuses. The AF samples from normal pregnancies were matched with the case samples in a 1:1 ratio based upon gestational age. The AF samples from the 34 fetuses were analyzed by liquid chromatography-mass spectrometry (LC-MS). Then, the peak areas of the metabolites were analyzed by principal component analysis (PCA), partial least squares discriminant analysis (PLS-DA) and univariate statistical analysis. RESULTS: This study ultimately identified 31 AAs. Seven differentially abundant AAs were screened out, including citrulline, ethanolamine, aspartic acid, valine, 5-hydroxylysine, proline, and isoleucine (p-value<0.05). A total of 4 metabolic pathways were significantly altered in the ICPC group: valine, leucine and isoleucine biosynthesis; valine, leucine and isoleucine degradation; pantothenate and coenzyme A (CoA) biosynthesis; and arginine biosynthesis. CONCLUSIONS: The results of this study indicate that fetuses with ICPC have disrupted levels of citrulline, ethanolamine, aspartic acid, valine, 5-hydroxylysine, proline, and isoleucine, which may ultimately affect fetal glucose and lipid metabolism.

Gene alternation of cerebrospinal fluid in patients with leptomeningeal metastases of lung adenocarcinoma using next-generation sequencing.

BACKGROUND: Epidermal growth factor receptor tyrosine kinase inhibitors (EGFR-TKIs) provide a better prognosis in EGFR-mutant non-small cell lung cancer (NSCLC). Nevertheless, the outcome of leptomeningeal metastasis (LM) remains poor. In addition, due to limited access to intracranial tumour tissue, gene alterations associated with leptomeningeal metastasis from lung adenocarcinoma (LM-LUAD) are unclear. METHODS: Forty-five patients with LM-LUAD from May 2019 to June 2021 in Guangdong Sanjiu Brain Hospital were enrolled in this study. Seventy-five percent (34/45) of patients with LM harbored EGFR mutations, and patients with progressive disease (PD) of LM had 3rd-generation EGFR-TKI therapy and were defined as Cohort 1; those without 3rd-generation EGFR-TKI therapy were defined as Cohort 2. Next-generation targeted panel sequencing (NGS) was performed in each cerebrospinal fluid (CSF) sample of the two cohorts, and 9/45 LM-LUAD patients had matched plasma (PLA). RESULTS: The common gene alterations discovered in the CSF of LM-LUAD were EGFR mutation (34/45, 75%), TP53 (25/45, 56%), CDKN2A (9/45, 20%), ALK (7/45, 16%), CTNNB1 (6/45, 13%), MET (5/45, 11%), APC (4/45, 9%), FGF4 (4/45, 9%), FGF3 (4/45, 9%), ERBB2 (4/45, 9%), and PIK3CG (4/45, 9%). Cooccurring mutations of TP53 and EGFR were found in 49% (22/45) of patients and correlated with poor prognosis. CDKN2A was identified in 20% (9/45) of patients and presented slightly shorter overall survival (OS) than those without (7.1 versus 8.8 months, p = 0.2). Cohort 1 had more genes associated with poor prognosis, consisting of CDK4, CDKN2A, PIK3CG, or PIK3CA, and YES1 and MET were more likely to be detected in cohort 2. The alteration of EGFR was comparable between CSF and matched PLA. Incidences of gene alterations such as CDK4, CDKN2A, MET, SOX2, JAK2, BRAF, and PIK3CG were more likely to be identified in CSF. All mutant allele frequencies (MAF) were much higher in CSF than in matched PLA. CONCLUSIONS: CSF could be a potential candidate for the genetic profiling of LM-LUAD, demonstrating the genetic characteristics of LM in EGFR-mutated lung adenocarcinoma on diverse EGFR-TKI therapies.

Protein-based prognostic signature for predicting the survival and immunotherapeutic efficiency of endometrial carcinoma.

BACKGROUND: Endometrial cancer (EC) is the most frequent malignancy of the female genital tract worldwide. Our study aimed to construct an effective protein prognostic signature to predict prognosis and immunotherapy responsiveness in patients with endometrial carcinoma. METHODS: Protein expression data, RNA expression profile data and mutation data were obtained from The Cancer Proteome Atlas (TCPA) and The Cancer Genome Atlas (TCGA). Prognosis-related proteins in EC patients were screened by univariate Cox regression analysis. Least absolute shrinkage and selection operator (LASSO) analysis and multivariate Cox regression analysis were performed to establish the protein-based prognostic signature. The CIBERSORT algorithm was used to quantify the proportions of immune cells in a mixed cell population. The Immune Cell Abundance Identifier (ImmuCellAI) and The Cancer Immunome Atlas (TCIA) web tools were used to predict the response to immunochemotherapy. The pRRophetic algorithm was used to estimate the sensitivity of chemotherapeutic and targeted agents. RESULTS: We constructed a prognostic signature based on 9 prognostic proteins, which could divide patients into high-risk and low-risk groups with distinct prognoses. A novel prognostic nomogram was established based on the prognostic signature and clinicopathological parameters to predict 1, 3 and 5-year overall survival for EC patients. The results obtained with Clinical Proteomic Tumor Analysis Consortium (CPTAC), Human Protein Atlas (HPA) and immunohistochemical (IHC) staining data from EC samples in our hospital supported the predictive ability of these proteins in EC tumors. Next, the CIBERSORT algorithm was used to estimate the proportions of 22 immune cell types. The proportions of CD8 T cells, T follicular helper cells and regulatory T cells were higher in the low-risk group. Moreover, we found that the prognostic signature was positively associated with high tumor mutation burden (TMB) and high microsatellite instability (MSI-H) status in EC patients. Finally, ImmuCellAI and TCIA analyses showed that patients in the low-risk group were more inclined to respond to immunotherapy than patients in the high-risk group. In addition, drug sensitivity analysis indicated that our signature had potential predictive value for chemotherapeutics and targeted therapy. CONCLUSION: Our study constructed a novel prognostic protein signature with robust predictive ability for survival and efficiency in predicting the response to immunotherapy, chemotherapy and targeted therapy. This protein signature represents a promising predictor of prognosis and response to cancer treatment in EC patients.

Cerebrospinal fluid-derived circulating tumor DNA is more comprehensive than plasma in NSCLC patients with leptomeningeal metastases regardless of extracranial evolution.

Introduction: Metastases to the central nervous system (CNS) are devastating neurological complications. Circulating cell-free tumor DNA (ctDNA) from cerebrospinal fluid (CSF) better represents genomic alterations in CNS tumors compared to plasma (PLA). However, the clinical value of cerebrospinal fluid (CSF) as a liquid biopsy medium in non-small cell lung cancer patients with leptomeningeal metastases (NSCLC-LM), regardless of extracranial evolution, remains unclear. Patients and methods: 14/48 NSCLC-BM patients and 34/48 NSCLC-LM patients were enrolled in this study. The genomic mutation profiles in CSF and matched PLA for patients with single CNS progression (cohort one, N = 22) or intracranial progression with extracranial disease progression (cohort two, N = 12) were compared. ctDNA in the CSF and simultaneously collected PLA was subjected to next-generation target sequencing (NGS) of 168 cancer-relevant genes. Results: CSF is more comprehensive of driver genomic mutation profile than in matched PLA in patients with a single CNS progression. In addition, potential prognostic markers are much higher in CSF samples than related PLA. For example, the detection rate of EGFR-amp in CSF was more than twice of the rate in matched PLA. Moreover, CDKN2A/B, PIK3CA/G, CDK4/6, and MET were detected uniquely in CSF samples and, all of these genetic mutations were correlated with poor outcomes.Almost all genetic mutation profiles detected in PLA could be seen in matched CSF samples in cohort two. With the driver genes, such as EGFR or ALK, have a higher detection rate in CSF compared to PLA. Moreover, the potential survival maker genes CDK4/6 (6/12, 50%), CDKN2A/B (2/12, 17%), EGFR-amp (1/12, 8%), MET (1/12, 8%), and PIK3CA (1/12, 8%) were unique to the CSF samples. Conclusion: For NSCLC -LM patients, regardless of single intracranial progression or intracranial progression simultaneously with extracranial evolution, CSF is superior to matched PLA.

Systemic characterization of alternative splicing related to prognosis and immune infiltration in malignant mesothelioma.

BACKGROUND: Malignant mesothelioma (MM) is a relatively rare and highly lethal tumor with few treatment options. Thus, it is important to identify prognostic markers that can help clinicians diagnose mesothelioma earlier and assess disease activity more accurately. Alternative splicing (AS) events have been recognized as critical signatures for tumor diagnosis and treatment in multiple cancers, including MM. METHODS: We systematically examined the AS events and clinical information of 83 MM samples from TCGA database. Univariate Cox regression analysis was used to identify AS events associated with overall survival. LASSO analyses followed by multivariate Cox regression analyses were conducted to construct the prognostic signatures and assess the accuracy of these prognostic signatures by receiver operating characteristic (ROC) curve and Kaplan-Meier survival analyses. The ImmuCellAI and ssGSEA algorithms were used to assess the degrees of immune cell infiltration in MM samples. The survival-related splicing regulatory network was established based on the correlation between survival-related AS events and splicing factors (SFs). RESULTS: A total of 3976 AS events associated with overall survival were identified by univariate Cox regression analysis, and ES events accounted for the greatest proportion. We constructed prognostic signatures based on survival-related AS events. The prognostic signatures proved to be an efficient predictor with an area under the curve (AUC) greater than 0.9. Additionally, the risk score based on 6 key AS events proved to be an independent prognostic factor, and a nomogram composed of 6 key AS events was established. We found that the risk score was significantly decreased in patients with the epithelioid subtype. In addition, unsupervised clustering clearly showed that the risk score was associated with immune cell infiltration. The abundances of cytotoxic T (Tc) cells, natural killer (NK) cells and T-helper 17 (Th17) cells were higher in the high-risk group, whereas the abundances of induced regulatory T (iTreg) cells were lower in the high-risk group. Finally, we identified 3 SFs (HSPB1, INTS1 and LUC7L2) that were significantly associated with MM patient survival and then constructed a regulatory network between the 3 SFs and survival-related AS to reveal potential regulatory mechanisms in MM. CONCLUSION: Our study provided a prognostic signature based on 6 key events, representing a better effective tumor-specific diagnostic and prognostic marker than the TNM staging system. AS events that are correlated with the immune system may be potential therapeutic targets for MM.

IL-7 and CCL19-secreting CAR-T cell therapy for tumors with positive glypican-3 or mesothelin.

Although chimeric antigen receptor (CAR)-engineered T cells have shown great success in the treatment of B cell malignancies, this strategy has limited efficacy in patients with solid tumors. In mouse CAR-T cells, IL-7 and CCL19 expression have been demonstrated to improve T cell infiltration and CAR-T cell survival in mouse tumors. Therefore, in the current study, we engineered human CAR-T cells to secrete human IL-7 and CCL19 (7 × 19) and found that these 7 × 19 CAR-T cells showed enhanced capacities of expansion and migration in vitro. Furthermore, 7 × 19 CAR-T cells showed superior tumor suppression ability compared to conventional CAR-T cells in xenografts of hepatocellular carcinoma (HCC) cell lines, primary HCC tissue samples and pancreatic carcinoma (PC) cell lines. We then initiated a phase 1 clinical trial in advanced HCC/PC/ovarian carcinoma (OC) patients with glypican-3 (GPC3) or mesothelin (MSLN) expression. In a patient with advanced HCC, anti-GPC3-7 × 19 CAR-T treatment resulted in complete tumor disappearance 30 days post intratumor injection. In a patient with advanced PC, anti-MSLN-7 × 19 CAR-T treatment resulted in almost complete tumor disappearance 240 days post-intravenous infusion. Our results demonstrated that the incorporation of 7 × 19 into CAR-T cells significantly enhanced the antitumor activity against human solid tumor. Trial registration: NCT03198546. Registered 26 June 2017, https://clinicaltrials.gov/ct2/show/NCT03198546?term=NCT03198546&draw=2&rank=1.

The tumor immune microenvironment and immune-related signature predict the chemotherapy response in patients with osteosarcoma.

BACKGROUND: Genome-wide expression profiles have been shown to predict the response to chemotherapy. The purpose of this study was to develop a novel predictive signature for chemotherapy in patients with osteosarcoma. METHODS: We analysed the relevance of immune cell infiltration and gene expression profiles of the tumor samples of good responders with those of poor responders from the TARGET and GEO databases. Immune cell infiltration was evaluated using a single-sample gene set enrichment analysis (ssGSEA) and the CIBERSORT algorithm between good and poor chemotherapy responders. Differentially expressed genes were identified based on the chemotherapy response. LASSO regression and binary logistic regression analyses were applied to select the differentially expressed immune-related genes (IRGs) and developed a predictive signature in the training cohort. A receiver operating characteristic (ROC) curve analysis was employed to assess and validate the predictive accuracy of the predictive signature in the validation cohort. RESULTS: The analysis of immune infiltration showed a positive relationship between high-level immune infiltration and good responders, and T follicular helper cells and CD8 T cells were significantly more abundant in good responders with osteosarcoma. Two hundred eighteen differentially expressed genes were detected between good and poor responders, and a five IRGs panel comprising TNFRSF9, CD70, EGFR, PDGFD and S100A6 was determined to show predictive power for the chemotherapy response. A chemotherapy-associated predictive signature was developed based on these five IRGs. The accuracy of the predictive signature was 0.832 for the training cohort and 0.720 for the validation cohort according to ROC analysis. CONCLUSIONS: The novel predictive signature constructed with five IRGs can be effectively utilized to predict chemotherapy responsiveness and help improve the efficacy of chemotherapy in patients with osteosarcoma.

Clinical analysis of bone metastasis of gastric cancer: incidence, clinicopathological features and survival.

Aim: We evaluated the incidence, clinicopathological features, prognostic factors and survival of gastric cancer (GC) with bone metastasis in a single large cancer center in China. Patients & methods: Patients with bone metastasis of GC were retrospectively analyzed. Overall survival was estimated using the Kaplan-Meier method. Clinicopathological factors, which were associated with prognostic factors for survival, were evaluated. Results: The incidence of bone metastasis was 11.3% for metastatic GC patients. Median overall survival time was 6.5 months. Multivariate analysis revealed two independent poor prognostic factors: Eastern Cooperative Oncology Group ≥2 (p = 0.023) and lack of palliative chemotherapy (p = 0.018). Conclusion: The incidence of bone metastasis from metastatic GC was underestimated. The prognosis of GC with bone metastasis was poor.

MiR-7-5p-mediated downregulation of PARP1 impacts DNA homologous recombination repair and resistance to doxorubicin in small cell lung cancer.

BACKGROUND: Chemo-resistance is one of the major challenges in the therapy of small cell lung cancer (SCLC). Multiple mechanisms are thought to be involved in chemo-resistance during SCLC treatment, but unfortunately, these mechanisms have not been well elucidated. Herein, we investigated the role of miRNA in the resistance of SCLC cells to doxorubicin (Dox). METHODS: MiRNA microarray analysis revealed that several miRNAs, including miR-7-5p, were specifically decreased in Dox-resistant SCLC cells (H69AR) compared to parental cells (H69). The expression level of miR-7-5p was confirmed by qRT-PCR in Dox-resistant cells (H69AR and H446AR cells) and their parental cells. Bioinformatic analysis indicated that poly ADP-ribose polymerase 1 (PARP1) is a direct target of miR-7-5p. The binding sites of miR-7-5p in the PARP1 3' UTR were verified by luciferase reporter and Western blot assays. To investigate the role of miR-7-5p in the chemo-resistance of SCLC cells to doxorubicin, mimic or inhibitor of miR-7-5p was transfected into SCLC cells, and the effect of miR-7-5p on homologous recombination (HR) repair was analyzed by HR reporter assays. Furthermore, the expression of HR repair factors (Rad51 and BRCA1) induced by doxorubicin was detected by Western blot and immunofluorescent staining in H446AR cells transfected with miR-7-5p mimic. RESULTS: The expression level of miR-7-5p was remarkably reduced (4-fold) in Dox-resistant SCLC cells (H69AR and H446AR cells) compared with that in parental cells (H69 and H446 cells). Poly ADP-ribose polymerase 1 (PARP1) is a direct target of miR-7-5p, and PARP1 expression was downregulated by miR-7-5p. MiR-7-5p impeded Dox-induced HR repair by inhibiting the expression of HR repair factors (Rad51 and BRCA1) that resulted in resensitizing SCLC cells to doxorubicin. CONCLUSIONS: Our findings provide evidence that miR-7-5p targets PARP1 to exert its suppressive effects on HR repair, indicating that the alteration of the expression of miR-7-5p may be a promising strategy for overcoming chemo-resistance in SCLC therapy.

Impact of synchronized anti-PD-1 with Ad-CEA vaccination on inhibition of colon cancer growth.

Aim: The purpose of this study was to determine whether addition of anti-PD-1 antibody increased the immunogenicity and anti-tumor activity of Ad-CEA vaccination in a murine model of colon cancer. Methods: Ad-CEA was administered prior to implantation of MC-38-CEA cells followed by administration of anti-PD-1 antibody. CEA-specific T-cell responses were measured by flow cytometry and ELISPOT. Dynamic co-culture of splenocytes with tumor cells was conducted to analyze anti-tumor activities. Tumor infiltration by lymphocytes was measured by IHC. Tumor volume and overall survival were also recorded. Results: Ad-CEA combined with anti-PD-1 antibody showed greater anti-tumor activity compared with either alone. The combination also increased T-cell infiltration but decreased Tregs. Conclusion: Combining Ad-CEA vaccination with anti-PD-1 antibody enhanced anti-tumor activity and immune responses.

Synthesis and assessment of drug-eluting microspheres for transcatheter arterial chemoembolization.

Transcatheter arterial chemoembolization (TACE) is well known as an effective treatment for inoperable hepatocellular carcinoma (HCC). In this study, a novel embolic agent of ion-exchange poly(hydroxyethyl methacrylate-acrylic acid) microspheres (HAMs) was successfully synthesized by the inverse suspension polymerization method. Then, HAMs were assessed for their activity as an embolic agent by investigating morphology, particle size, water retention capability, elasticity and viscoelasticity, microcatheter/catheter deliverability, cytotoxicity, renal arterial embolization to rabbits and histopathological examinations. The ability of drug loading and drug eluting of HAMs was also investigated by using doxorubicin (Dox) as the model drug. HAMs showed to be feasible and effective for vascular embolization and to be as a drug vehicle for loading positively charged molecules and potential use in the clinical interventional chemoembolization therapy. STATEMENT OF SIGNIFICANCE: A novel embolic agent of ion-exchange poly(hydroxyethyl methacrylate-acrylic acid) microspheres (HAMs) was successfully synthesized by the inverse suspension polymerization method and was used as a drug vehicle to load positively charged molecules by ion absorption. Then, a series of assessments including physicochemical properties, mechanical properties, drug-loading capability, and embolic efficacy were performed. Surface and cross-section morphology and pore size of fully hydrated HAMs were first investigated by Phenom ProX SEM, which intuitively disclosed the "honeycomb" network morphology. HAMs also showed to be feasible and effective for vascular occlusion and have potential use in clinical interventional embolization therapy.

Oxidized Vitamin C (DHA) Overcomes Resistance to EGFR-targeted Therapy of Lung Cancer through Disturbing Energy Homeostasis.

Switching aerobic respiration to anaerobic glycolysis of cancer cells plays an important role in development and progression of acquired resistance. Since vitamin C enabled the inhibition of glycolysis of cancer cells, and erlotinib-resistant sub-line of HCC827 (ER6 cells) switched its metabolic features to higher glycolysis for survival, we hypothesize that vitamin C is able to inhibit glycolysis of ER6 cells. In this study, we found that both reduced vitamin C and oxidized vitamin C (DHA) could selectively suppress the viability of ER6 cells. DHA was efficient in inhibiting glycolysis and leading to energy crisis, which could be one mechanism for overcoming drug resistance to erlotinib of ER6 cells. Our data suggest that applying DHA could be a novel treatment strategy for NSCLC with acquired resistance to targeted therapy.

Artesunate-Loaded and Near-Infrared Dye-Conjugated Albumin Nanoparticles as High-Efficiency Tumor-Targeted Photo-Chemo Theranostic Agent.

Herein, a tumor-targeted multifunctional theranostic agent was synthetized using a facile method, combining four clinically approved materials: artesunate (Arte), human serum albumin (HSA), folic acid (FA), and indocyanine green (ICG). The obtained nanocomposites (FA-IHA NPs) showed an excellent photo- and physiological stability. The ICG in the FA-IHA NPs was used not only for near infrared (NIR) fluorescence imaging, but also for photothermal and photodynamic (PTT-PDT) therapy under a single NIR irradiation. In addition, the NIR irradiation (808 nm, 1 W/cm2) could trigger Arte release that showed enhanced chemotherapeutic effect. Through fluorescence imaging, the cell uptake and tumor accumulation of FA-IHA NPs were observed in vitro and in vivo, analyzed by confocal microscopy and NIR fluorescence imaging in tumor xenograft mice. Based on the diagnostic results, FA-IHA NPs at 24 h post injection and combined with NIR irradiation (808 nm, 1 W/cm2) could efficiently suppress tumor growth through a photo-chemo combination therapy, with no tumor recurrence in vitro and in vivo. The obtained results suggested that FA-IHA NPs are promising photo-chemo theranostic agents for future clinical translation.