The Cousa objective: a long-working distance air objective for multiphoton imaging in vivo.

Multiphoton microscopy can resolve fluorescent structures and dynamics deep in scattering tissue and has transformed neural imaging, but applying this technique in vivo can be limited by the mechanical and optical constraints of conventional objectives. Short working distance objectives can collide with compact surgical windows or other instrumentation and preclude imaging. Here we present an ultra-long working distance (20 mm) air objective called the Cousa objective. It is optimized for performance across multiphoton imaging wavelengths, offers a more than 4 mm2 field of view with submicrometer lateral resolution and is compatible with commonly used multiphoton imaging systems. A novel mechanical design, wider than typical microscope objectives, enabled this combination of specifications. We share the full optical prescription, and report performance including in vivo two-photon and three-photon imaging in an array of species and preparations, including nonhuman primates. The Cousa objective can enable a range of experiments in neuroscience and beyond.

Does resection after neoadjuvant chemotherapy of docetaxel, oxaliplatin, and S-1 (DOS regimen) benefit for gastric cancer patients with single non-curable factor? a multicenter, prospective cohort study (Neo-REGATTA).

BACKGROUND: The Neo-REGATTA study evaluated the effectiveness and safety of Docetaxel, oxaliplatin, and S-1 (DOS regimen) followed by radical resection vs. chemotherapy in advanced gastric adenocarcinoma patients with single non-curable factor. METHODS: This cohort study prospectively enrolled advanced gastric adenocarcinoma patients with single non-curable factor between November 2017 and June 2021. Patients without progression after four cycles of DOS were divided into resection group and chemotherapy group. The outcomes included overall survival (OS), progression-free survival (PFS) and safety. Effectiveness analysis was also performed by propensity score matching (PSM). RESULTS: A total of 73 patients were enrolled and 13 patients were withdrawn due to disease progression after 4 cycles of DOS. Afterwards, 35 and 25 participants were in the resection and chemotherapy groups, respectively. After a median follow-up time of 30.0 months, the median PFS and OS were 9.0 months, and 18.0 months for the chemotherapy group, but not reached in the resection group. After PSM, 19 matched participants were in each group, and the median PFS and OS were longer in resection group than that in chemotherapy group. The most common grade 3 or 4 adverse events both in the resection group and chemotherapy groups were neutropenia (5.7%, 8.0%) and leukopenia (5.7%, 8.0%). CONCLUSIONS: Radical resection might provide survival benefit compared with continuous chemotherapy alone in advanced gastric adenocarcinoma patients who had a disease control after DOS, with a good safety profile. TRIAL REGISTRATION: The study protocol was registered on ClinicalTrial.gov (NCT03001726, 23/12/2016).

Synovial mesenchymal stem cell-derived exosomal microRNA-320c facilitates cartilage damage repair by targeting ADAM19-dependent Wnt signalling in osteoarthritis rats.

OBJECTIVE: Our previous study revealed that synovial mesenchymal stem cell (SMSC)-derived exosomal microRNA-302c enhanced chondrogenesis by targeting a disintegrin and metalloproteinase 19 (ADAM19) in vitro. This study aimed to validate the potential of SMSC-derived exosomal microRNA-302c for the treatment of osteoarthritis in vivo. METHODS: After 4 weeks of destabilization of the medial meniscus surgery (DMM) to establish an osteoarthritis model, the rats received weekly articular cavity injection of SMSCs with or without GW4869 treatment (exosome inhibitor) or exosomes from SMSCs with or without microRNA-320c overexpression for another 4 weeks. RESULTS: SMSCs and SMSC-derived exosomes reduced the Osteoarthritis Research Society International (OARSI) score, improved cartilage damage repair, suppressed cartilage inflammation, suppressed extracellular matrix (ECM) degradation, and inhibited chondrocyte apoptosis in DMM rats. However, these effects were largely hampered in rats that were injected with GW4869-treated SMSCs. Moreover, exosomes from microRNA-320c-overexpressing SMSCs exerted a better effect than exosomes from negative control SMSCs on decreasing the OARSI score, enhancing cartilage damage repair, suppressing cartilage inflammation, and inhibiting ECM degradation and chondrocyte apoptosis. Mechanistically, exosomes from microRNA-320c-overexpressing SMSCs reduced the levels of ADAM19, as well as ß-catenin and MYC, which are two critical proteins in Wnt signalling. CONCLUSION: SMSC-derived exosomal microRNA-320c suppresses ECM degradation and chondrocyte apoptosis to facilitate cartilage damage repair in osteoarthritis rats by targeting ADAM19-dependent Wnt signalling.

Neoadjuvant apatinib combined with oxaliplatin and capecitabine in patients with locally advanced adenocarcinoma of stomach or gastroesophageal junction: a single-arm, open-label, phase 2 trial.

BACKGROUND: Adding anti-angiogenics to neoadjuvant chemotherapy for localized gastric cancer is recognized as a promising strategy, but its clinical value remains to be defined. METHODS: This single-center, single-arm, phase 2 trial included patients with locally advanced (cT3/4aN+M0) adenocarcinoma of the stomach or gastroesophageal junction (GEJ) who received three cycles of intravenous oxaliplatin (135 mg/m2 on day 1), oral capecitabine (1000 mg/m2 twice daily on days 1 to 14), and oral apatinib for 21 days (250 mg once daily in the first two cycles, and further increased to 500 mg daily in the third cycle based on whether any adverse event of grade 3 or worse occurred), and an additional cycle of oxaliplatin plus capecitabine, followed by gastrectomy with D2 lymphadenectomy. The primary endpoint was the proportion of patients who achieved an objective response according to RECIST version 1.1. RESULTS: Between April 28, 2017, and October 23, 2019, 37 patients were screened and 35 participants were included. Of the 32 patients assessable for efficacy and safety, objective responses were achieved in 25 (78.1%; 95% confidence interval [CI], 60.0% to 90.7%) patients. Thirty-one (96.9%) patients received R0 resection, two (6.3%) patients achieved pathological complete response, and 11 (34.4%) patients achieved pathological response. At the data cutoff date (September 30, 2021), the median event-free survival was 42.6 (95% CI, 16.2 to not reached) months, and the median overall survival was not reached. The most common grade 3 or 4 treatment-emergent adverse events were hypertension (9/32, 28.1%), thrombocytopenia (7/32, 21.9%), and neutropenia (5/32, 15.6%). Seven (21.9%) patients developed surgical complications, and the most common one was intra-abdominal abscess (4/32, 12.5%). CONCLUSIONS: The concomitant use of apatinib, oxaliplatin, and capecitabine as neoadjuvant therapy showed promising efficacy and manageable safety profile in patients with locally advanced adenocarcinoma of the stomach or GEJ, and further phase 3 study is warranted. TRIAL REGISTRATION: This study was registered with ClinicalTrial.gov ( NCT03229096 ).

Efficacy of AS versus SOX regimen as first-line chemotherapy for gastric cancer patients with peritoneal metastasis: a real-world study.

BACKGROUND: To compare the prognosis of first-line systemic chemotherapy of AS (Albumin-bound paclitaxel and S-1) versus SOX (S-1 and oxaliplatin) regimen in Chinese gastric cancer patients with peritoneal metastasis. METHODS: This was a real-world study of gastric cancer patients with peritoneal metastasis who have been treated with AS or SOX regimen as first-line chemotherapy. Patients were matched by the method of propensity score matching (PSM). The primary and secondary endpoints were overall survival (OS) and progress-free survival (PFS). RESULTS: A total of 108 gastric cancer patients with peritoneal metastasis were enrolled after PSM analysis. There was no significant difference between AS and SOX regimen based on gender, age, ascites, treatment cycles, gastric cancer resection, received checkpoint inhibitors, and HER-2 expression after PSM analysis. The median OS (14.13 vs. 11.17 months, p = 0.0356) and median PFS (10.30 vs. 6.70 months, p = 0.0003) of patients who received AS regimen were longer than those treated by SOX regimen as first-line systemic chemotherapy. In sub-group analysis, the median OS and median PFS were longer for patients in AS regimen than SOX regimen in Lauren diffuse type. The occurrence of toxicity between the two groups was shown no significant difference. CONCLUSIONS: The results verified that AS regimen was more effective than SOX chemotherapy in gastric cancer patients with peritoneal metastasis, especially in Lauren diffuse type.

Targeted Discovery of Amantamide B, an Ion Channel Modulating Nonapeptide from a South China Sea Oscillatoria Cyanobacterium.

Amantamide B (1) is a new linear nonapeptide analogue of the cyanobacterial natural product amantamide A (2), and both have methyl ester and butanamide termini. These compounds were discovered in this study from the organic extract of a tropical marine filamentous cyanobacterium, Oscillatoria sp., collected around the Paracel Islands in the South China Sea. The use of LC-MS/MS molecular networking for sample prioritization and as an analytical dereplication tool facilitated the targeted isolation of 1 and 2. These molecules were characterized by spectroscopy and spectrometry, and configurational assignments were determined using chemical degradation and chiral-phase HPLC analysis. Compounds 1 and 2 modulated spontaneous calcium oscillations without notable cytotoxicity at 10 µM in short duration in vitro testing on primary cultured neocortical neurons, a model system that evaluates neuronal excitability and/or the potential activity on Ca2+ signaling. Both molecules were also found to be moderately cytotoxic in longer duration bioassays, with in vitro IC50 values of 1-10 µM against CCRF-CEM human T lymphoblastoid cells and U937 human histiocytic lymphoma cells. These formerly undiscovered bioactivities of known compound 2 expand upon its previously reported function as a selective CXCR7 agonist among 168 GPCR targets.

Tumor-derived LIF promotes chemoresistance via activating tumor-associated macrophages in gastric cancers.

Chemotherapy is the preferred clinical treatment for advanced stage gastric cancer (GC) patients, of which efficacy could be markedly impaired due to the development of chemoresistance. Alternatively activated or M2-type tumor associated macrophages (TAMs) are recruited under chemotherapy and are highly implicated in the chemoresistance development, but underlying molecular mechanism for TAM activation is largely unknown. Here, we present that tumor-derived Leukemia inhibitory factor (LIF) induced by chemo drugs represses the chemo sensitivity of gastric tumor cells in a TAM-dependent manner. Mechanistically, cisplatin-induced HIF1α signaling activation directly drive the transcription of LIF, which promotes the resistance of gastric tumors to chemo drug. Further study revealed that tumor cell-derived LIF stimulates macrophages into tumor-supporting M2-type phenotype via activating STAT3 signaling pathway. Therapeutically, blocking LIF efficiently elevates chemo sensitivity of tumor cells and further represses the growth rates of tumors under chemotherapy. Therefore, our study reveals a novel insight in understanding the cross talking between tumor cells and immune cells and provides new therapeutic targets for gastric cancer.

Influence of perinatal deltamethrin exposure at distinct developmental stages on motor activity, learning and memory.

BACKGROUND: Perinatal exposure to deltamethrin (DM) causes attention-deficit/ hyperactivity disorder-like behaviors. However, the vulnerable time window to DM exposure and the possible mechanism are obscure. We aimed to identify the critical window(s) at perinatal stages for DM exposure and the possible mechanism. METHOD: Pregnant mice were exposed to DM (0.5 mg/kg) at three different prenatal stages [gestational day (GD) 0-5, 6-15 and 16-birth (16-B)] and early postnatal stage (PD 0-10). Locomotor activity, learning and memory were evaluated using open field and Y-maze test, respectively. Nissl staining and western blots were used to examine the neuronal loss and the protein expression, respectively. RESULTS: Perinatal exposures to DM had no effect on reproductive and growth index of offspring. However, mice receiving DM exposure during GD 16-B displayed significantly higher mortality suggesting GD 16-B is the most vulnerable time window to DM exposure. Prenatal but not early postnatal DM exposure impaired locomotor activity, learning and memory, and caused neuron loss in the dentate gyrus of male offspring. However, neither prenatal nor postnatal DM exposure affected mouse behavior of female offspring. Prenatal DM exposures decreased the protein levels of NR2A and NR2B in both hippocampi and cerebral cortices of male offspring. However, female mice receiving DM exposure at GD 16-B but not other stages displayed increased expression levels of NR2A and NR2B in hippocampi. CONCLUSION: Prenatal but not early postnatal DM exposure impairs the neuron development in male but not female mice. Altered NMDA receptor expression may correlate to DM-induced behavioral deficits.

Identification of immune checkpoint and cytokine signatures associated with the response to immune checkpoint blockade in gastrointestinal cancers.

Immune checkpoint blockade (ICB) of the programmed cell death 1/programmed cell death ligand 1 (PD-1/PD-L1) immune checkpoint pathway has led to unprecedented advances in cancer therapy. However, the overall response rate of anti-PD-1/PD-L1 monotherapy is still unpromising, underscoring the need for predictive biomarkers. In this retrospective study, we collected pretreatment plasma samples from two independent cohorts of patients receiving ICB. To determine whether a signature of plasma cytokines could be associated with therapeutic efficacy, we systemically profiled cytokine clusters and functional groups in the discovery and validation datasets by using 59 multiplexed bead immunoassays and bioinformatics analysis. We first attempted to functionally classify the 59 immunological factors according to their biological classification or functional roles in the cancer-immunity cycle. Surprisingly, we observed that two signatures, the "checkpoint signature" and "trafficking of T-cell signature", were higher in the response subgroup than in the nonresponse subgroup in both the discovery and validation cohorts. Moreover, enrichment of the "checkpoint signature" was correlated with improved overall survival and progression-free survival in both datasets. In addition, we demonstrated that increased baseline levels of three checkpoint molecules (PD-L1, T-cell immunoglobulin mucin receptor 3 and T-cell-specific surface glycoprotein CD28) were common peripheral responsive correlates in both cohorts, thus rendering this "refined checkpoint signature" an ideal candidate for future verification. In the peripheral blood system, the "refined checkpoint signature" may function as a potential biomarker for anti-PD-1/PD-L1 monotherapy in gastrointestinal (GI) cancers.

Identification of key genes involved in tumor immune cell infiltration and cetuximab resistance in colorectal cancer.

BACKGROUND: The anti-epidermal growth factor receptor (EGFR) antibody introduces adaptable variations to the transcriptome and triggers tumor immune infiltration, resulting in colorectal cancer (CRC) treatment resistance. We intended to identify genes that play essential roles in cetuximab resistance and tumor immune cell infiltration. METHODS: A cetuximab-resistant CACO2 cellular model was established, and its transcriptome variations were detected by microarray. Meanwhile, public data from the Gene Expression Omnibus and The Cancer Genome Atlas (TCGA) database were downloaded. Integrated bioinformatics analysis was applied to detect differentially expressed genes (DEGs) between the cetuximab-resistant and the cetuximab-sensitive groups. Then, we investigated correlations between DEGs and immune cell infiltration. The DEGs from bioinformatics analysis were further validated in vitro and in clinical samples. RESULTS: We identified 732 upregulated and 1259 downregulated DEGs in the induced cellular model. Gene Ontology and Kyoto Encyclopedia of Genes and Genomes pathway enrichment analyses, along with Gene Set Enrichment Analysis and Gene Set Variation Analysis, indicated the functions of the DEGs. Together with GSE59857 and GSE5841, 12 common DEGs (SATB-2, AKR1B10, ADH1A, ADH1C, MYB, ATP10B, CDX-2, FAR2, EPHB2, SLC26A3, ORP-1, VAV3) were identified and their predictive values of cetuximab treatment were validated in GSE56386. In online Genomics of Drug Sensitivity in Cancer (GDSC) database, nine of twelve DEGs were recognized in the protein-protein (PPI) network. Based on the transcriptome profiles of CRC samples in TCGA and using Tumor Immune Estimation Resource Version 2.0, we bioinformatically determined that SATB-2, ORP-1, MYB, and CDX-2 expressions were associated with intensive infiltration of B cell, CD4+ T cell, CD8+ T cell and macrophage, which was then validated the correlation in clinical samples by immunohistochemistry. We found that SATB-2, ORP-1, MYB, and CDX-2 were downregulated in vitro with cetuximab treatment. Clinically, patients with advanced CRC and high ORP-1 expression exhibited a longer progression-free survival time when they were treated with anti-EGFR therapy than those with low ORP-1 expression. CONCLUSIONS: SATB-2, ORP-1, MYB, and CDX-2 were related to cetuximab sensitivity as well as enhanced tumor immune cell infiltration in patients with CRC.

Whole-tumour evaluation with MRI and radiomics features to predict the efficacy of S-1 for adjuvant chemotherapy in postoperative pancreatic cancer patients: a pilot study.

BACKGROUND: Multiple guidelines for pancreatic ductal adenocarcinoma (PDAC) suggest that all stages of patients need to receive postoperative adjuvant chemotherapy. S-1 is a recently emerged oral antitumour agent recommended by the guidelines. However, which population would benefit from S-1 needs to be determined, and predictors of chemotherapy response are needed for personalized precision medicine. This pilot study aimed to initially identify whether whole-tumour evaluation with MRI and radiomics features could be used for predicting the efficacy of S-1 and to find potential predictors of the efficacy of S-1 as evidence to assist personalized precision treatment. METHODS: Forty-six patients with PDAC (31 in the primary cohort and 15 in the validation cohort) who underwent curative resection and subsequently adjuvant chemotherapy with S-1 were included. Pre-operative abdominal contrast-enhanced MRI was performed, and radiomics features of the whole PDAC were extracted from the primary cohort. After univariable analysis and radiomics features selection, a multivariable Cox regression model for survival analysis was subsequently used to select statistically significant factors associated with postoperative disease-free survival (DFS). Predictive capacities of the factors were tested on the validation cohort by using Kaplan-Meier method. RESULTS: Multivariable Cox regression analysis identified the probability of T1WI_NGTDM_Strength and tumour location as independent predictors of the efficacy of S-1 for adjuvant chemotherapy of PDAC (p = 0.005 and 0.013) in the primary cohort, with hazard ratios (HRs) of 0.289 and 0.293, respectively. Further survival analysis showed that patients in the low-T1WI_NGTDM_Strength group had shorter DFS (median = 5.1 m) than those in the high-T1WI_NGTDM_Strength group (median = 13.0 m) (p = 0.006), and patients with PDAC on the pancreatic head exhibited shorter DFS (median = 7.0 m) than patients with tumours in other locations (median = 20.0 m) (p = 0.016). In the validation cohort, the difference in DFS between patients with low-T1WI_NGTDM_Strength and high-T1WI_NGTDM_Strength and the difference between patients with PDAC on the pancreatic head and that in other locations were approved, with marginally significant (p = 0.073 and 0.050), respectively. CONCLUSIONS: Whole-tumour radiomics feature of T1WI_NGTDM_Strength and tumour location were potential predictors of the efficacy of S-1 and for the precision selection of S-1 as adjuvant chemotherapy regimen for PDAC.

Cross-platform comparison of next-generation sequencing and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry for detecting KRAS/NRAS/BRAF/PIK3CA mutations in cfDNA from metastatic colorectal cancer patients.

BACKGROUND: Examining tumor KRAS/NRAS/BRAF/PIK3CA status in metastatic colorectal cancer (mCRC) is essential for treatment selection and prognosis evaluation. Cell-free DNA (cfDNA) in plasma is a feasible source for tumor gene analysis. METHODS: In this study, we recruited mCRC patients and analyzed their KRAS/NRAS/BRAF/PIK3CA status in cfDNA using two platforms, next-generation sequencing (NGS) and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF). The performance between the two platforms and the concordance rate between cfDNA and tissue were analyzed. The relationship between cfDNA-related variables and clinical variables was also assessed. Tumor mutations in cfDNA from patients receiving continuous treatments were monitored in the follow-ups. RESULTS: Next-generation sequencing and MALDI-TOF had similar specificity (100.0% vs. 99.3%) and negative predictive value (99.9% vs. 99.4%), whereas NGS had higher sensitivity (97.1% vs. 85.3% of MALDI-TOF) and positive predictive value (100% vs. 82.9% of MALDI-TOF). The overall concordance rate of NGS and MALDI-TOF was 98.6%. For the reportable types of mutations in both cfDNA and tissue, the concordance rate was 96.1%. Among 28 tissue-positive patients, the allele frequencies of tumor mutations in cfDNA were higher in patients with primary tumor burden (p = 0.0141). Both CEA and CA 19-9 were positively correlated with cfDNA concentration (r = 0.3278 and r = 0.3992). The allele frequencies of tumor mutations changed with disease progression. CONCLUSIONS: Next-generation sequencing showed slightly better performance in detecting cfDNA mutations and was more suitable for clinical practice. cfDNA-related variables reflected the tumor status and showed a promising potential in monitoring disease progression.

A 16-mRNA signature optimizes recurrence-free survival prediction of Stages II and III gastric cancer.

High-throughput messenger RNA (mRNA) analysis has become a powerful tool for exploring tumor recurrence or metastasis mechanisms. Here, we constructed a signature to predict the recurrence risk of Stages II and III gastric cancer (GC) patients. A least absolute shrinkage and selection operator method Cox regression model was utilized to construct the signature. Using this method, a 16-mRNA signature was identified to be associated with the relapse-free survival of Stages II and III GCs in training dataset GSE62254 (n = 194). Then this signature was validated in an independent Gene Expression Omnibus cohort GSE26253 (n = 297) and a dataset of The Cancer Genome Atlas (TCGA; n = 235). This classifier could successfully screen out the high-risk Stages II and III GCs in the training cohort (hazard ratio [HR] = 40.91; 95% confidence interval [CI] = 5.58-299.7; p < .0001). Analysis in two independent validation cohorts yielded consistent results (GSE26253: HR = 1.69, 95% CI = 1.17-2.43,; p = .0045; TCGA: HR = 2.01, 95% CI = 1.13-3.56, p = .0146). Cox regression analyses revealed that the risk score derived from this signature was an independent risk factor in Stages II and III GCs. Besides, a nomogram was constructed to serve clinical practice. Through gene set variation analysis, we found several gene sets associated with chemotherapeutic drug resistance and tumor metastasis significantly enriched in high-risk patients. In summary, this 16-mRNA signature can be used as a powerful tool for prognostic evaluation and help clinicians identify high-risk patients.

Identification of a Novel EHBP1-MET Fusion in an Intrahepatic Cholangiocarcinoma Responding to Crizotinib.

As an aggressive tumor, intrahepatic cholangiocarcinoma (ICC) originates in the epithelium of the bile duct and has a poor prognosis. The therapeutic options for ICC are challenging and limited because of poor response to chemotherapy and the lack of targeted therapy. Here we report on a 41-year-old female patient with ICC with EHBP1-MET fusion and multiple intrahepatic metastases responding to crizotinib. Next-generation sequencing-based tumor mutation profiling was performed on the tumor biopsy and circulating tumor DNA from plasma. A novel EHBP1-MET fusion was identified and confirmed by Sanger sequencing. Immunohistochemistry of biopsy sample also revealed c-MET positivity. Subsequently, the patient started treatment with MET inhibitor crizotinib. Magnetic resonance imaging scan demonstrated a partial response for 8 months. To the best of our knowledge, this is the first clinical case report of a patient with MET-rearranged ICC successfully treated with crizotinib. This case suggests that crizotinib may be a promising treatment option for patients with ICC with MET fusion, warranting further clinical investigation. KEY POINTS: To the authors' knowledge, this is the first reported case of EHBP1-MET fusion. This is also the first clinical case report of clinical benefit from crizotinib treatment in an intrahepatic cholangiocarcinoma (ICC) with MET fusion. MET fusion is rare in ICC, and inhibition of MET could be a viable option for ICC that warrants further clinical investigation.

Activated HIF1α of tumor cells promotes chemoresistance development via recruiting GDF15-producing tumor-associated macrophages in gastric cancer.

Chemotherapy is the preferred treatment for advanced stage gastric cancer (GC) patients, and developing chemoresistance is a tremendous challenge to efficacy of GC treatment. The treatments of anti-tumor chemo-agents recruit more tumor-associated macrophages (TAMs) which are highly implicated in the chemoresistance development, but the underlying molecular mechanism is unclear. Here, we demonstrate that hypoxia-inducible factor 1α (HIF1α) in GC cells is activated upon 5-fluorouracil (5-FU) treatment and results in much more accumulation of M2-type TAMs which protect tumor cells from chemo-agents. Mechanistically, in the GC cells under the 5-FU treatment, reactive oxygen species is accumulated and then induces the activation of HIF1α signaling to drive the expression of high-mobility group box 1, which leads to more macrophage's infiltration into GC tumor. In turn, the recruited TAMs exhibit tumor-protected M2-type phenotype and promote the chemoresistance of GC cells via producing growth differentiation factor 15 (GDF15) to exacerbate the fatty acid ß-oxidation in tumor cells. Blocking GDF15 using antibody or inhibiting FAO of tumor cells by etomoxir efficiently gave rise to the tumor cell sensitivity to 5-FU. Therefore, our study demonstrates a novel insight in understanding the cross talking between tumor cells and immune microenvironment and provides new therapeutic targets for clinic treatments of gastric cancer.

Familial juvenile polyposis syndrome with a de novo germline missense variant in BMPR1A gene: a case report.

BACKGROUND: Juvenile polyposis syndrome (JPS) is a rare autosomal dominant hereditary disorder characterized by the development of multiple distinct juvenile polyps in the gastrointestinal tract with an increased risk of colorectal cancer. Germline mutations in two genes, SMAD4 and BMPR1A, have been identified to cause JPS. CASE PRESENTATION: Here, we report a germline heterozygous missense variant (c.299G > A) in exon 3 BMPR1A gene in a family with juvenile polyposis. This variant was absent from the population database, and concluded as de novo compared with the parental sequencing. Further sequencing of the proband's children confirmed the segregation of this variant with the disease, while the variant was also predicted to have damaging effect based on online prediction tools. Therefore, this variant was classified as likely pathogenic according to the American College of Medical Genetics and Genomics (ACMG) guidelines. CONCLUSIONS: Germline genetic testing revealed a de novo germline missense variant in BMPR1A gene in a family with juvenile polyposis. Identification of the pathogenic variant facilitates the cancer risk management of at-risk family members, and endoscopic surveillance is recommended for mutation carriers.

Role of circulating free DNA in evaluating clinical tumor burden and predicting survival in Chinese metastatic colorectal cancer patients.

BACKGROUND: The aim of this study was to explore the utility of circulating free DNA (cfDNA) in the evaluation of clinical tumor burden and survival in Chinese patients with metastatic colorectal cancer (mCRC) and to preliminarily summarize some metastatic characteristics associated with mutational status. METHODS: A panel covering a total of 197 hotspot mutations of KRAS, NRAS, BRAF and PIK3CA was used to evaluate the mutational status in plasma by next-generation sequencing (NGS) technology in 126 patients with mCRC. An amplification-refractory mutation system (ARMS) was used to analyze genomic DNA from matched tissue samples. Clinical markers including carcinoembryonic antigen (CEA), carbohydrate antigen 199 (CA199), carbohydrate antigen 125 (CA125), neuron-specific enolase (NSE) and lactate dehydrogenase (LDH) in serum and the sum of all tumor diameters on CT or PET/CT were collected to indicate clinical tumor burden. The correlations between cfDNA and clinical tumor burden were analyzed using Pearson correlation and linear regression models. The median progression-free survival (PFS) and 1-year overall survival (OS) rates were calculated by Kaplan-Meier (K-M) survival analysis. RESULTS: Of the 126 enrolled patients, patients who were tested positive for mutations in plasma accounted for 45.2% (57/126). Mutations in KRAS, NRAS, BRAF and PIK3CA were detected in 37.3% (47/126), 1.6% (2/126), 3.2% (4/126) and 13.5% (17/126) of patients, respectively. The overall concordance rate of mutational status between plasma and matched tissues was 78.6% (99/126). Sixteen patients had mutations in plasma that were not detected in tissue, including some rare hotspot mutations. The cfDNA concentration was significantly correlated with the levels of clinical markers, especially CEA (P < 0.0001, Pearson r = 0.81), LDH (P < 0.0001, Pearson r = 0.84) and the sum of tumor diameters (P < 0.0001, Pearson r = 0.80). Patients with a high cfDNA concentration (> 17.91 ng/ml) had shorter median progression-free survival (6.6 versus 11.7 months, P < 0.0001) and lower 1-year overall survival rate (56% versus 94%, P < 0.0001) than those with a low cfDNA concentration (≤17.91 ng/ml). The most common metastatic site was the liver (77.8%), followed by the lymph nodes (62.7%), lung (40.5%), peritoneum (14.3%) and bone (10.3%), in all patients. There was no significant difference in metastasis between different mutational statuses. CONCLUSION: Analyzing mutations in plasma could provide a more comprehensive overview of the mutational landscape than analyzing mutations in tissue. The cfDNA concentration could be a quantitative biomarker of tumor burden and could predict survival in Chinese patients with mCRC.

Oxaliplatin plus Capecitabine in the Perioperative Treatment of Locally Advanced Gastric Adenocarcinoma in Combination with D2 Gastrectomy: NEO-CLASSIC Study.

LESSONS LEARNED: The NEO-CLASSIC study provided valuable insight for the clinical efficacy and tolerability profiles of perioperative chemotherapy with oxaliplatin and capecitabine, plus gastrectomy, in patients with localized resectable gastric cancer.The study was designed to explore the potential survival benefits of an eight-cycle, perioperative oxaliplatin and capecitabine (XELOX) schedule in the above-mentioned setting and to explore the feasibility of prolonging the cycles of preoperative chemotherapy. The projected endpoint was not met. BACKGROUND: This multicenter, open-label study (NEO-CLASSIC) evaluated the efficacy and safety of oxaliplatin and capecitabine (XELOX), plus D2 gastrectomy, in localized resectable gastric cancer. METHODS: Patients aged 18-75 years with histologically-confirmed gastric adenocarcinoma (stage T2-4a/N+M0) were given eight cycles of XELOX (four preoperatively, four postoperatively). Each 3-week cycle comprised capecitabine 1,000 mg/m2 twice daily on days 1-14 and oxaliplatin 130 mg/m2 on day 1. Curative D2 gastrectomy was scheduled 2-4 weeks after the last preoperative cycle. The primary objective of the study was to determine the objective response rate (ORR) of XELOX in the preoperative setting. Sample size was calculated by assuming that a minimum of 47 cases would be required to increase the ORR by 15% (from 40% to 55%). With an estimated 10% dropout rate, 55 patients would have to be recruited. RESULTS: Fifty-five patients were enrolled, and one was excluded because of screening failure. R0 resections were achieved in 45 of 54 intent-to-treat patients (83.3%), and four patients received R1 resections (Fig. 1). There were no complete responses, 27 (50.0%) partial responses, 22 cases (40.7%) of stable disease, and 4 (7.4%) of progressive disease. The objective response rate was 50.0%. Median follow-up was 52.97 months; 30 patients (55.6%) had disease progression (Table 1), and median progression-free survival was 20.10 (95% confidence interval: 4.31-35.89) months; median overall survival was 30.77 months (95% confidence interval was not yet available) (Fig. 2). Fifty-four patients completed 209 cycles of preoperative chemotherapy; 42 patients received 133 cycles of postoperative chemotherapy (Table 3). The rate of grade 3-4 adverse events was 8.5% (29/342 cycles); the most frequent events were neutropenia (9/342 cycles) and leukopenia (4/342 cycles). CONCLUSION: These findings suggest that combination therapy with capecitabine and oxaliplatin as perioperative chemotherapy, followed by D2 gastrectomy, is effective and safe in late-stage, locally advanced gastric cancer. Although enrollment exceeded the 47 patients required to identify an increase in the ORR by 15% (from 40% to 55%), results did not meet the primary endpoint.

The role of oxaliplatin in the adjuvant setting of different Lauren's type of gastric adenocarcinoma after D2 gastrectomy: a real-world study.

BACKGROUND: To compare the efficacy of oxaliplatin-based and oxaliplatin-free adjuvant chemotherapies in patients with different Lauren type gastric cancers after D2 gastrectomy. METHODS: From our established gastric cancer database, patients with pathological stage II and III gastric cancer who received adjuvant chemotherapy after D2 gastrectomy at Zhongshan Hospital of Fudan University were analyzed. Patients who received different adjuvant chemotherapy regimens were divided into two subgroups: oxaliplatin-based and oxaliplatin-free subgroup. Clinical outcomes were analyzed according to pathological stage and different Lauren types. RESULTS: From Jan 2010 to June 2017, a total of 580 patients met all the eligibility criteria and were enrolled. The median DFS for all the patients was 24.37 months and the median OS was 56.70 months. In patients with intestinal type gastric cancer, the median DFS of the oxaliplatin-based subgroup was significantly longer than that of oxaliplatin-free subgroup (48.73 vs. 18.33 months, P < 0.001). The median OS was not reached in the oxaliplatin-based subgroup and 54.33 months in the oxaliplatin-free subgroup (P = 0.006). In patients with diffuse type gastric cancer, neither DFS nor OS differed significantly between two subgroups. In multivariate analysis, oxaliplatin-based adjuvant chemotherapy was independent positive predictor of DFS (HR 0.40; 95% CI 0.28-0.59; P < 0.001) and OS (HR 0.35; 95% CI 0.20-0.62; P < 0.001) in patients with intestinal type gastric cancer. CONCLUSIONS: The results of our study suggested that oxaliplatin-based adjuvant chemotherapy was more effective in patients with intestinal type gastric cancer after D2 gastrectomy but showed no more survival benefit in patients with diffuse type.

Analytical and clinical validation of a novel amplicon-based NGS assay for the evaluation of circulating tumor DNA in metastatic colorectal cancer patients.

Background Evaluating the tumor RAS/BRAF status is important for treatment selection and prognosis assessment in metastatic colorectal cancer (mCRC) patients. Correction of artifacts from library preparation and sequencing is essential for accurately analyzing circulating tumor DNA (ctDNA) mutations. Here, we assessed the analytical and clinical performance of a novel amplicon-based next-generation sequencing (NGS) assay, Firefly™, which employs a concatemer-based error correction strategy. Methods Firefly assay targeting KRAS/NRAS/BRAF/PIK3CA was evaluated using cell-free DNA (cfDNA) reference standards and cfDNA samples from 184 mCRC patients. Plasma results were compared to the mutation status determined by ARMS-based PCR from matched tissue. Samples with a mutation abundance below the limit of detection (LOD) were retested again by droplet digital polymerase chain reaction (ddPCR) or NGS. Results The Firefly assay demonstrated superior sensitivity and specificity with a 98.89% detection rate at an allele frequency (AF) of 0.2% for 20 ng cfDNA. Generally, 40.76% and 48.37% of the patients were reported to be positive by NGS of plasma cfDNA and ARMS of FFPE tissue, respectively. The concordance rate between the two platforms was 80.11%. In the pre-treatment cohort, the concordance rate between plasma and tissue was 93.33%, based on the 17 common exons that Firefly™ and ARMS genotyped, and the positive percent agreement (PPA) and negative percent agreement (NPA) for KRAS/NRAS/BRAF/PIK3CA were 100% and 99.60%, respectively. Conclusions Total plasma cfDNA detected by Firefly offers a viable complement for mutation profiling in CRC patients, given the high agreement with matched tumor samples. Together, these data demonstrate that Firefly could be routinely applied for clinical applications in mCRC patients.