The roles of PD-L1 in the various stages of tumor metastasis.

The interaction between tumor programmed death ligand 1 (PD-L1) and T-cell programmed cell death 1 (PD-1) has long been acknowledged as a mechanism for evading immune surveillance. Recent studies, however, have unveiled a more nuanced role of tumor-intrinsic PD-L1 in reprograming tumoral phenotypes. Preclinical models emphasize the synchronized effects of both intracellular and extracellular PD-L1 in promoting metastasis, with intricate interactions with the immune system. This review aims to summarize recent findings to elucidate the spatiotemporal heterogeneity of PD-L1 expression and the pro-metastatic roles of PD-L1 in the entire process of tumor metastasis. For example, PD-L1 regulates the epithelial-to-mesenchymal transition (EMT) process, facilitates the survival of circulating tumor cells, and induces the formation of immunosuppressive environments at pre-metastatic niches and metastatic sites. And the complexed and dynamic regulation process of PD-L1 for tumor metastasis is related to the spatiotemporal heterogeneity of PD-L1 expression and functions from tumor primary sites to various metastatic sites. This review extends the current understandings for the roles of PD-L1 in mediating tumor metastasis and provides new insights into therapeutic decisions in clinical practice.

Reclassification of RAS/BRAF allele mutations predicts the survival benefit of triplet chemotherapy in metastatic colorectal cancer.

Background: Different RAS/BRAF allele mutations imply distinct biological properties in various solid tumors. Recently, several studies have focused on the predictive and prognostic roles of various RAS/BRAF allele mutations in colorectal cancer (CRC) but the results remain controversial. Methods: Between March 2017 and September 2022, the patients diagnosed as stages I-IV CRC with detailed medical records including next-generation sequencing (NGS) data and clinicopathological follow-up information available at our center were enrolled. Survival data were estimated using the Kaplan-Meier method, and the difference was tested in a log-rank test. Multivariate tests were carried out using Cox models. Results: A total of 1029 CRC patients were included, and the incidence of RAS/BRAF mutation was 58.4%. The hypermutated cohort was defined as patients with microsatellite instability-H or POLE/D mutation. In the non-hypermutational cohort, only KRAS G13D mutation was associated with a higher incidence and inferior disease-free survival in patients with stage I-III CRC. In the cohort of patients with non-hypermutated metastatic colorectal cancer (mCRC), we assessed the risk of various RAS/BRAF allele mutations and subsequently reclassified patients into four groups based on first-line median progression-free survival: wild type (group 1), low-risk RAS/BRAF mutation (group 2, RAS/BRAF mutations other than KRAS G13D/G12V/G12C or BRAF V600E), high-risk RAS mutation (group 3, KRAS G13D/G12V/G12C), and BRAF V600E mutation (group 4). mCRC patients with high-risk RAS mutation could significantly benefit from intensive triplet chemotherapy (hazard ratio, 2.54; 95% confidence interval, 1.36-5.12; p = 0.0091). Conclusion: In the non-hypermutated CRC cohort, the prognostic risk of various RAS/BRAF allele mutations varied between local and metastatic CRC. KRAS G13D mutation tended to be the only prognostic marker for stages I-III CRC; however, KRAS G13D/G12V/G12C mutations collectively defined a high-risk subgroup of mCRC patients with poor prognosis, who would benefit from intensive triplet chemotherapy.

Intestinal Autotransplantation for Locally Advanced or Locally Recurrent Colon Cancer Invading SMA.

OBJECTIVE: To examine the outcomes of intestinal autotransplantation (IATx) in patients with locally advanced or recurrent colon cancer (LACC or LRCC) invading the superior mesenteric artery (SMA). BACKGROUND: SMA Involvement in LACC or LRCC is deemed unresectable and is associated with a poor prognosis. Combined extended resections of multiple organs together with SMA, followed by IATx may offer favorable clinical outcomes. However, data on its safety and efficacy are scarce. DESIGN: This retrospective cohort study included patients undergoing IATx between May 2018 and December 2022 in intestinal transplant programs at two university-affiliated hospitals in China. Patients with LACC or LRCC concomitantly with SMA contact of more than 180° were included. Patients with a locoregional peritoneal, pelvic, or distal metastasis were excluded. RESULTS: Ten patients underwent either IATx combined with pancreaticoduodenectomy (n=8) or IATx alone (n=2). Eight patients (80%) were male, and the median age was 55 years (range, 32 - 71 y). The Kaplan-Meier estimates for recurrence-free survival and overall survival at 3 years after IATx were 68% and 80%, respectively. No perioperative deaths occurred. All ten patients experienced postoperative complications including Clavien-Dindo grade I (n=1), grade II (n=4), grade IIIa (n=1), grade IIIb (n=3) and grade IVa (n=1), which comprised acute venous thromboses, upper gastrointestinal hemorrhage, anastomotic leak, gastropareses and significant pleural effusions. With an average follow-up of 23.9 months, eight patients (80%) were currently alive without evidence of disease. CONCLUSION: Extended resection for LACC or LRCC invading SMA can be performed safely and is associated with prolonged survival.

High-throughput single nucleus total RNA sequencing of formalin-fixed paraffin-embedded tissues by snRandom-seq.

Formalin-fixed paraffin-embedded (FFPE) tissues constitute a vast and valuable patient material bank for clinical history and follow-up data. It is still challenging to achieve single cell/nucleus RNA (sc/snRNA) profile in FFPE tissues. Here, we develop a droplet-based snRNA sequencing technology (snRandom-seq) for FFPE tissues by capturing full-length total RNAs with random primers. snRandom-seq shows a minor doublet rate (0.3%), a much higher RNA coverage, and detects more non-coding RNAs and nascent RNAs, compared with state-of-art high-throughput scRNA-seq technologies. snRandom-seq detects a median of >3000 genes per nucleus and identifies 25 typical cell types. Moreover, we apply snRandom-seq on a clinical FFPE human liver cancer specimen and reveal an interesting subpopulation of nuclei with high proliferative activity. Our method provides a powerful snRNA-seq platform for clinical FFPE specimens and promises enormous applications in biomedical research.

Metastatic sites and lesion numbers cooperated to predict efficacy of PD-1 inhibitor-based combination therapy for patients with metastatic colorectal cancer.

BACKGROUND: Limited data have been used to evaluate the efficacy of immunotherapy in metastatic colorectal cancer (mCRC). Furthermore, potential markers that can be used to identify responding patients and to further improve efficacy have not been fully explored. METHODS AND RESULTS: In our study, we included a total of 97 patients with mCRC, who each received programmed death-1 (PD-1) inhibitor-based combination therapy at our center. All 12 hypermutated patients benefited from immunotherapy, with median progression-free survival (mPFS) reaching 28.3 months, regardless of liver metastasis. The objective response rate (ORR) of non-hypermutated patients was 16.5% (14/85), with an mPFS of 4.0 months. For non-hypermutated patients, multivariate analysis revealed that the combination of liver metastasis and baseline lesion number significantly stratified response and survival. The lesion-based analysis indicated that the lymph node was the most responsive, followed by the peritoneum and lung, with liver metastasis being the least responsive. None of the patients (0/7) with negative programmed ligand-1 (PD-L1) expression responded, and positive PD-L1 expression may serve as a biomarker (mPFS 5.7 vs. 2.2 months, p = 0.002) that can be used to further guide treatment in non-hypermutated mCRC with liver metastasis (CRLMs). CONCLUSION: Patients with hypermutated mCRC benefited significantly from immunotherapy, whereas the non-hypermutated cohort with liver metastasis and numerous lesions showed less benefit. The lesion sites reflected varying levels of efficacy, among which PD-L1 potentially cooperated to guide the immunotherapy of CRLMs.

Soluble PD-L1: a potential dynamic predictive biomarker for immunotherapy in patients with proficient mismatch repair colorectal cancer.

BACKGROUND: Circulating soluble programmed death ligand 1 (sPD-L1) can negatively regulate T-cell function and serve as a prognostic or predictive marker in a variety of cancers. However, rare studies have evaluated the potential roles of sPD-L1, and no study has estimated its predictive value for the efficacy of immune treatment in colorectal cancer (CRC). METHODS: Plasma samples from 192 CRC patients were used to estimate correlations between clinicopathological features and sPD-L1, secreted PD-L1 (secPD-L1) and exosomal PD-L1 (exoPD-L1). Baseline and posttreatment sPD-L1 levels were also investigated in 55 patients with metastatic CRC (mCRC) treated with chemotherapy ± targeted therapy and 40 patients with proficient mismatch repair (pMMR) mCRC treated with combination immunotherapy. Both sPD-L1 and secPD-L1 were quantified by enzyme-linked immunosorbent assay, while exoPD-L1 was analyzed using flow cytometry. RESULTS: secPD-L1 was the major component and positively correlated with sPD-L1 in CRC, while exoPD-L1 was almost undetectable. Higher levels of sPD-L1 were detected in patients with distant metastasis, especially those with distant lymph node metastasis and tissue combined positive score (CPS) instead of tumor proportion score (TPS). Chemotherapy or targeted therapy did not significantly impact sPD-L1 concentration. Progressive disease on combination immunotherapy was associated with an increase in sPD-L1 level, whereas no significant change was observed in patients with durable clinical benefit. CONCLUSION: sPD-L1 mainly consisted of secPD-L1, and its level was higher in patients with distant metastasis, especially distant lymph node metastasis and positive CPS. sPD-L1 is a potential dynamic marker to identify rapid progression on combination immunotherapy and avoid ineffective treatment for pMMR CRC.

Development of a Humanized VHH Based Recombinant Antibody Targeting Claudin 18.2 Positive Cancers.

Claudin 18.2 (CLDN18.2), a tight junction (TJ) family protein controlling molecule exchange between cells, is frequently over-expressed in gastric cancer, pancreatic adenocarcinomas and in a fraction of non-small cell lung cancer cases. The tumor properties indicate that CLDN18.2 could be an attractive drug target for gastric and pancreatic cancers. In this study, we present effective strategies for developing anti-CLDN18.2 therapeutic candidates, based on variable domain of heavy chain of heavy chain antibodies (VHHs). CLDN18.2-specific VHHs were isolated by panning a phage display library from an alpaca immunized with a stable cell line highly expressing CLDN18.2. Humanized VHHs fused with human IgG1 Fc, as potential therapeutic candidates, exhibited desirable binding specificity and affinity to CLDN18.2. In vitro experiments showed that hu7v3-Fc was capable of eliciting both antibody-dependent cellular cytotoxicity (ADCC) and complement-dependent cytotoxicity (CDC) on CLDN18.2 positive tumor cells. In the mouse xenograft model, the anti-tumor efficacy of hu7v3-Fc was significantly more potent than Zolbetuximab, the benchmark anti-CLDN18.2 monoclonal antibody. Moreover, in vivo biodistribution using zirconium-89 (89Zr) labeled antibodies demonstrated that hu7v3-Fc (89Zr-hu7v3-Fc) exhibited a better tumor penetration and a faster tumor uptake than Zolbetuximab (89Zr-Zolbetuximab), which might be attributed to its smaller size and higher affinity. Taken together, anti-CDLN18.2 hu7v3-Fc is a promising therapeutic agent for human CLDN18.2 positive cancers. Furthermore, hu7v3 has emerged as a potential module for novel CLDN18.2 related therapeutics.

[Clinical Characteristics and Prognosis of Children with Myelodysplastic Syndrome].

OBJECTIVE: To analyze the clinical characteristics and prognosis of 40 children with myelodysplastic syndrome (MDS), and provide ideas for clinical diagnosis and treatment. METHODS: The clinical characteristics, risk stratification, and different treatment regimens of 40 cases with MDS admitted in Department of Hematology of Children's Hospital of Soochow University from January 1, 2011 to December 31, 2017 was retrospectively analyzed. Kaplan-Meier survival curve were used to estimate 3-year overall survival (OS) rate and event-free survival (EFS) rate. RESULTS: In 40 cases, the ratio of male to female was 1.4∶1.0, male was more than female, and median age was 6.0 years old. Among them, refractory cytopenia (MDS-RCC) was the most common type, and 11 cases were chromosomal abnormalities, 21 cases genetic abnormalities. Fifteen cases accepted hematopoietic stem cell transplantation (HSCT) treatment, while 25 cases did not but drug therapy alone. The 3-year OS rate of the cases who accepted HSCT or not was (72.2±12.2)% and (35.3±10.2)% (P=0.039), 3-year EFS rate was (65.0±12.9)% and (19.2±8.4)% (P=0.012), respectively. Cox regression analysis showed that age < 7 years old (P=0.0333), initial diagnosed platelet < 50×109/L (P=0.007), presence of complex karyotypes and/or gene mutations (P=0.0002), and treatment without HSCT (P=0.016) were the high-risk factors of prognosis. All the children were classified according to IPSS, WPSS and IPSS-R, while analysis result showed that the above three risk assessment had limitations for risk assessment of MDS in children, they could not comprehensively assess the prognosis of children with MDS. CONCLUSION: MDS-RCC in children is more common. Cox multivariate analysis shows that age < 7 years old, initial diagnosed platelet < 50×109/L, presence of complex karyotypes and/or gene mutation, and treatment without HSCT are the high-risk factors of prognosis in children with MDS. HSCT is the most effective treatment to cure children with MDS at present. The current methods such as IPSS-R commonly used in assessment of prognosis in children with MDS show obvious limitation.

Genomic and transcriptomic analysis of MSI-H colorectal cancer patients with targetable alterations identifies clinical implications for immunotherapy.

Introduction: Targetable alterations such as BRAFV600E mutation and NTRK fusion are enriched in microsatellite instability-high (MSI-H) colorectal cancer (CRC). MSI-H with targetable alterations (MSI-H altered) might present unique opportunities for both targeted therapy and immunotherapy. We systematically evaluated the molecular characteristics and immune-related features of MSI-H altered and MSI-H without targetable alterations (MSI-H wt) CRC patients in our study. Methods: Among 1938 continuously enrolled CRC patients, 126 patients with MSI-H status (6.50%) were included in this retrospective study. Genomic and transcriptomic data were investigated by next-generation sequencing (NGS) and gene expression profiling (GEP), respectively. Results: BRAFV600E, NTRK1, and FGFR2 mutations were the most frequent targetable alterations in MSI-H CRC patients. The MSI-H altered phenotype was significantly associated with older age (p< 0.001), right side (p=0.024) and females (p= 0.036). No lynch syndrome (LS) patients were identified in MSI-H altered group. The tumor mutational burden (TMB), and tumor neoantigen burden (TNB) of MSI-H altered and wt subgroups were comparable (p<0.05). Subsequently, transcriptomic study analysis further revealed MSI-H altered CRC patients were linked to an immune-active tumor microenvironment with higher levels of Teff IFN-gamma, CYT, and MERCK 18 signatures, and lower levels of the IPRES gene signature, EMT and TGF Beta signatures. In addition, case study supported MSI-H CRC patient harboring targetable alterations might also achieved a long-term disease-free survival benefit from immunotherapy. Discussion: Our study preliminary revealed MSI-H altered as a novel subtype of MSI-H CRC patients with unique molecular signatures and immune-active tumor microenvironment. Given the accessibility of immune checkpoint inhibitors (ICIs) treatment, our results might provide clinical evidence for immunotherapy in MSI-H CRC patients with targetable alterations.

TOD-CUP: a gene expression rank-based majority vote algorithm for tissue origin diagnosis of cancers of unknown primary.

Gene expression profiling holds great potential as a new approach to histological diagnosis and precision medicine of cancers of unknown primary (CUP). Batch effects and different data types greatly decrease the predictive performance of biomarker-based algorithms, and few methods have been widely applied to identify tissue origin of CUP up to now. To address this problem and assist in more precise diagnosis, we have developed a gene expression rank-based majority vote algorithm for tissue origin diagnosis of CUP (TOD-CUP) of most common cancer types. Based on massive tissue-specific RNA-seq data sets (10 553) found in The Cancer Genome Atlas (TCGA), 538 feature genes (biomarkers) were selected based on their gene expression ranks and used to predict tissue types. The top scoring pairs (TSPs) classifier of the tumor type was optimized by the TCGA training samples. To test the prediction accuracy of our TOD-CUP algorithm, we analyzed (1) two microarray data sets (1029 Agilent and 2277 Affymetrix/Illumina chips) and found 91% and 94% prediction accuracy, respectively, (2) RNA-seq data from five cancer types derived from 141 public metastatic cancer tumor samples and achieved 94% accuracy and (3) a total of 25 clinical cancer samples (including 14 metastatic cancer samples) were able to classify 24/25 samples correctly (96.0% accuracy). Taken together, the TOD-CUP algorithm provides a powerful and robust means to accurately identify the tissue origin of 24 cancer types across different data platforms. To make the TOD-CUP algorithm easily accessible for clinical application, we established a Web-based server for tumor tissue origin diagnosis (http://ibi. zju.edu.cn/todcup/).

Effects of mid-stage nitrogen application timing on the morphological structure and physicochemical properties of japonica rice starch.

BACKGROUND: Nitrogen management of crops, especially when mid-stage nitrogen is applied, is a key factor affecting the yield and grain quality of rice (Oryza sativa). Here, the timing of mid-stage nitrogen application was evaluated for its effect on rice grain quality by assessing the morphological structure and physicochemical properties of starch from two japonica rice cultivars growing in fields (Nangeng 9108 and Nangeng 5055). RESULTS: The experiment was arranged in a split-plot design, with the two rice cultivars as the main plot factor and three timings of mid-stage nitrogen application as the within-plot factor. Briefly, three applications were made: at the emergence of the top-sixth-leaf (ahead), the top-fourth-leaf (normal), and the top-second-leaf (delayed) of the main stem. Delaying mid-stage nitrogen application caused the starch granule surface to become uneven and significantly reduced its particle size, whereas it increased the polished rice rate, chalkiness degree, and protein content. Furthermore, the apparent amylose content decreased with a delay in mid-stage nitrogen application, thereby resulting in higher relative crystallinity, swelling power, water solubility, gelatinization enthalpy, and low retrogradation. Finally, we also found that delaying this nitrogen application lowered the characteristic values of rice flour viscosities, leading to cooking quality deterioration. CONCLUSION: These results therefore suggest that delaying mid-stage nitrogen application enhances the processing and nutritional qualities of japonica rice but evidently has an adverse effect upon its appearance and cooking qualities. © 2020 Society of Chemical Industry.

Whole-exome sequencing reveals potential mechanisms of drug resistance to FGFR3-TACC3 targeted therapy and subsequent drug selection: towards a personalized medicine.

BACKGROUND: Drug resistance is a major obstacle to effective cancer therapy. In order to detect the change in tumor genomic states under drug selection pressure, we use next-generation sequencing technology to investigate the underlying potential mechanisms of drug resistance. METHODS: In our study, we presented a bladder cancer patient who had been a bona fide responder to first-line gemcitabine plus cisplatin regimen and second-line pazopanib (tyrosine kinase inhibitor (TKI) for FGFR3-TACC3 fusion) but finally had disease progression as an ideal case for showing genomic alteration during drug resistance. We applied whole-exome sequencing and ultra-deep target sequencing to the patient pre- and post- pazopanib resistance. Protein-protein interaction (PPI) network and Gene Ontology (GO) analyses were used to analysis protein interactions and genomic alterations. Patient-derived xenograft (PDX) model was built to test drug sensitivity. RESULTS: Twelve mutations scattered in 12 genes were identified by WES pre- pazopanib resistance, while 63 mutations in 50 genes arose post- pazopanib resistance. PPI network showed proteins from multiple epigenetic regulator families were involved post- pazopanib resistance, including subunits of chromatin remodeler SWI/SNF complex ARID1A/1B and SMARCA4, histone acetylation writers CREBBP, histone methylation writer NSD1 and erasers KDM6A/5A. GO enrichment analysis showed pazopanib resistance genes were prominently tagged for chromatin modification, transcription, as well as gland development, leaving genes with the best adaptive FGFR TKI-coping mechanisms. In addition, significantly elevated tumor mutational burden suggested possible utility of immunotherapy. Intriguingly, PDX model suggested that, sensitivity to original chemotherapy regimen (cisplatin) was restored in patient tumor post-pazopanib. CONCLUSIONS: Epigenetic regulation may play a role in acquired TKI resistance. Our study traced the complete tumor genomic variation course from chemo-resistant but TKI-sensitive to TKI-resistant but chemo-(re) sensitive, revealing the potential complex dynamic drug-driven mechanisms of resistance.

Evaluation of multiplex ARMS-PCR for detection of Helicobacter pylori mutations conferring resistance to clarithromycin and levofloxacin.

BACKGROUND: Helicobacter pylori bacterium is a major cause of gastritis. With increasing use of antibiotics to treat infections, mutation resistant strains have emerged in most human populations. To effectively treat patients to help resolve infections, the clinician needs information on the antibiotic susceptibility profile of the infection. Therefore, a rapid and accurate test is required to provide this information. To address this issue, we designed and validated a real time multiplex ARMS-PCR assay for rapid detection of highly prevalent H. pylori clarithromycin and levofloxacin resistance mutations. The aim of the study was to evaluate the analytical and diagnostic sensitivity and specificity of ARMS-PCR, using direct Sanger sequencing of the known resistance mutations as the gold standard. RESULTS: In preliminary studies using a defined number of plasmids with clarithromycin and levofloxacin resistance mutations, the analytical sensitivity of our ARMS-PCR assay was 50 plasmid copies, equating to around 50 bacterium in a gastric biopsy sample. In terms of specificity, the assay was highly specific for the targeted resistance mutations. The assay was also able to reliably and efficiently detect heteroresistance of clarithromycin and levofloxacin mutations, even at a disproportional ratio of 1:1000. From the analysis of 192 samples with suspected H. pylori infections, the diagnostic sensitivity and specificity of the assay was very high for detection of clarithromycin resistance (100% and 100%), levofloxacin resistance (98.04% and 95.04%) and clarithromycin and levofloxacin double resistance (100% and 96.91%). Amongst the 74 patients diagnosed antibiotic resistance bacteria, 23 (31.1%) had clarithromycin resistance, 21 (28.4%) had levofloxacin resistance and 30 (40.5%) had double resistance. From sample receipt to results, our single tube assay could be routinely completed in under 2 h. CONCLUSIONS: Our assay demonstrated high diagnostic sensitivity and specificity for detection of clarithromycin and levofloxacin resistant H. pylori. Based on proven accuracy, together with high efficiency, scalability and low cost, our assay has useful clinical utility for rapid diagnosis of clarithromycin and levofloxacin resistant H. pylori infections. Our assay results will provide patients with a clear diagnosis, enabling the treating clinician to administer the most effective antibiotic regimen to help the clear the infection.

Anti-PD-1/PD-L1 Blockade Immunotherapy Employed in Treating Hepatitis B Virus Infection-Related Advanced Hepatocellular Carcinoma: A Literature Review.

Hepatitis B virus (HBV) infection is regarded as the main etiological risk factor in the process of hepatocellular carcinoma (HCC), as it promotes an immunosuppressive microenvironment that is partially mediated by the programmed cell death protein 1 (PD-1)/programmed death-ligand 1 (PD-L1) signaling pathway. The tumor microenvironment (TME) of HBV-related HCC is indeed more immunosuppressive than microenvironments not associated with viruses. And compared to TME in hepatitis C virus (HCV) infected HCC, TME of HBV-related HCC is less vascularized and presents different immune components resulting in similar immunosuppression. However, few studies are focusing on the specific side effects and efficacy of PD-1/PD-L1 blockade immunotherapy in HBV-related HCC patients, as well as on the underlying mechanism. Herein, we reviewed the basic research focusing on potential TME alteration caused by HBV infection, especially in HCC patients. Moreover, we reviewed PD-1/PD-L1 blockade immunotherapy clinical trials to clarify the safety and efficacy of this newly developed treatment in the particular circumstances of HBV infection. We found that patients with HBV-related HCC displayed an acceptable safety profile similar to those of non-infected HCC patients. However, we could not determine the antiviral activity of PD-1/PD-L1 blockade because standard anti-viral therapies were conducted in all of the current clinical trials, which made it difficult to distinguish the potential influence of PD-1/PD-L1 blockade on HBV infection. Generally, the objective response rates (ORRs) of PD-1/PD-L1 blockade immunotherapy did not differ significantly between virus-positive and virus-negative patients, except that disease control rates (DCRs) were obviously lower in HBV-infected HCC patients.

Dynamic alterations of genome and transcriptome in KRAS G13D mutant CRC PDX model treated with cetuximab.

BACKGROUND: KRAS mutations have been characterized as the major predictive biomarkers for resistance to cetuximab treatment. However, studies indicate that not all KRAS mutations are associated with equivalent treatment outcomes. KRAS G13D mutations were observed to account for approximately 16% of all KRAS mutations in advanced colorectal cancer patients, and whether these patients can benefit from cetuximab has not been determined. METHODS: An established KRAS G13D mutant colorectal cancer (CRC) patient-derived xenograft (PDX) model was treated with cetuximab. After repeated use of cetuximab, treatment-resistant PDX models were established. Tissue samples were collected before and during treatment, and multiomics data were subsequently sequenced and processed, including whole-exome, mRNA and miRNA data, to explore potential dynamic changes. RESULTS: Cetuximab treatment initially slowed tumor growth, but resistance developed not long after treatment. WES (whole-exome sequencing) and RNA sequencing found that 145 genes had low P values (< 0.01) when analyzed between the locus genotype and its related gene expression level. Among these genes, SWAP70 was believed to be a probable cause of acquired resistance. JAK2, PRKAA1, FGFR2 and RALBP1, as well as 10 filtered immune-related genes, also exhibited dynamic changes during the treatment. CONCLUSIONS: Cetuximab may be effective in KRAS G13D mutation patients. Dynamic changes in transcription, as determined by WES and RNA sequencing, occurred after repeated drug exposure, and these changes were believed to be the most likely cause of drug resistance.

Nutrition and metabolism status alteration in advanced hepatocellular carcinoma patients treated with anti-PD-1 immunotherapy.

PURPOSE: The aim of this study was to evaluate the nutrition and metabolism status alteration during immunotherapy in advanced hepatocellular carcinoma (HCC) patients. METHODS: Patients with advanced HCC who participated in the clinical trials of single-agent anti-PD-1 immunotherapy or sorafenib were retrospectively included. We analyzed self-comparison of the nutritional and metabolic indices of patients in the anti-PD-1 and sorafenib treatment group. We conducted mutual-comparison of the mentioned indices between the disease progression group and disease control group among anti-PD-1 treatment patients. We further analyzed those indices with statistical differences by partial correlation and survival analysis. RESULTS: Both self-comparison before and after treatment in the anti-PD-1 group and mutual-comparison of disease progression and the control group showed significant differences in multiple indices, but we did not observe significant differences in the sorafenib group. Strikingly, albumin (ALB)/prognostic nutritional index (PNI, calculated by serum albumin and lymphocyte count) decreased distinctly in the immunotherapy disease progression group patients. However, changes in ALB/PNI were not significant in disease progression patients from the sorafenib group or in the disease control patients with immunotherapy. Partial correlation analysis suggested that ALB and PNI were positively correlated with the efficacy of immunotherapy. Furthermore, survival analysis showed that the median progression-free survival and median overall survival of patients in the ALB/PNI decreased group were significantly shorter than those of patients from the ALB/PNI increased group. CONCLUSION: Anti-PD-1 immunotherapy might alter the nutritional and metabolic status in advanced HCC patients. We also should pay attention to the nutritional and metabolic status of patients when drug resistance is detected.

Exhausted CD8+T Cells in the Tumor Immune Microenvironment: New Pathways to Therapy.

Tumor-specific CD8+T cells are exposed to persistent antigenic stimulation which induces a dysfunctional state called "exhaustion." Though functioning to limit damage caused by immune response, T cell exhaustion leads to attenuated effector function whereby cytotoxic CD8+T cells fail to control tumor progression in the late stage. This pathway is a dynamic process from activation to "progenitor exhaustion" through to "terminally exhaustion" with distinct properties. With the rapid development of immunotherapy via enhancing T cell function, new studies are dissecting the mechanisms and identifying specific biomarkers of dynamic differentiation during the process of exhaustion. Further, although immune checkpoint inhibitors (ICIs) have achieved great success in clinical practice, most patients still show limited efficacy to ICIs. The expansion and differentiation of progenitor exhausted T cells explained the success of ICIs while the depletion of the progenitor T cell pool and the transient effector function of terminally exhausted T cells accounted for the failure of immune monotherapy in the context of exorbitant tumor burden. Thus, combination strategies are urgent to be utilized based on the reduction of tumor burden or the expansion of the progenitor T cell pool. In this review, we aim to introduce the concept of homeostasis of the activated and exhausted status of CD8+T cells in the tumor immune microenvironment, and present recent findings on dynamic differentiation process during T cell exhaustion and the implications for combination strategies in immune therapy.

Adult sacrococcygeal teratoma: a retrospective study over eight years at a single institution.

OBJECTIVE: To determine the clinical, imaging, and histological features, and surgical resection modalities and outcomes of adult sacrococcygeal teratoma (SCT). METHODS: Adult patients with histopathologically diagnosed SCT were enrolled in our hospital between August 2010 and August 2018. Each patient's characteristics and clinical information were reviewed. RESULTS: There were 8 patients in the study (2 males, 6 females) with a median age of 34 years (range, 18-67 years). The time to clinical symptoms was 14 d to 35 years, with a median time of 4 years. Six patients presented with symptoms of sacrococcygeal pain, and four with signs of sacrococcygeal mass and ulceration in the sacrococcygeal region. Six patients were evaluated using a combination of computed tomography (CT) and magnetic resonance imaging (MRI). All patients showed a presacral tumor with heterogeneous intensity on CT images. All patients underwent surgical treatment, including 6 parasacral, 1 transabdominal, and 1 combined anterior-posterior surgery cases. Seven patients were histopathologically diagnosed with benign mature SCT, and have shown no recurrence. One patient had malignant SCT, with recurrence at 84 months after surgery. After a second surgery, the patient had no recurrence within 6 months follow-up after re-resection. CONCLUSIONS: Our retrospective study demonstrated: (1) adult SCT is difficult to diagnose because of a lack of typical clinical symptoms and signs; (2) a combination of CT and MRI examination is beneficial for preoperative diagnosis; (3) the choice of surgical approach and surgical resection modality depends on the size, location, and components of the tumor, which can be defined from preoperative CT and MRI evaluation; (4) most adult SCTs are benign; the surgical outcome for the malignant SCT patient was good after complete resection. Even for the patient with recurrent malignant SCT, the surgical outcome was good after re-resection.

Gut microbiome affects the response to anti-PD-1 immunotherapy in patients with hepatocellular carcinoma.

BACKGROUND: Checkpoint-blockade immunotherapy targeting programmed cell death protein 1 (PD-1) has recently shown promising efficacy in hepatocellular carcinoma (HCC). However, the factors affecting and predicting the response to anti-PD-1 immunotherapy in HCC are still unclear. Herein, we report the dynamic variation characteristics and specificities of the gut microbiome during anti-PD-1 immunotherapy in HCC using metagenomic sequencing. RESULTS: Fecal samples from patients responding to immunotherapy showed higher taxa richness and more gene counts than those of non-responders. For dynamic analysis during anti-PD-1 immunotherapy, the dissimilarity of beta diversity became prominent across patients as early as Week 6. In non-responders, Proteobacteria increased from Week 3, and became predominant at Week 12. Twenty responder-enriched species, including Akkermansia muciniphila and Ruminococcaceae spp., were further identified. The related functional genes and metabolic pathway analysis, such as carbohydrate metabolism and methanogenesis, verified the potential bioactivities of responder-enriched species. CONCLUSIONS: Gut microbiome may have a critical impact on the responses of HCC patients treated with anti-PD-1 immunotherapy. The dynamic variation characteristics of the gut microbiome may provide early predictions of the outcomes of immunotherapy in HCC, which is critical for disease-monitoring and treatment decision-making.

Antibiotics and immunotherapy in gastrointestinal tumors: Friend or foe?

The incidence of gastrointestinal (GI) tumors is increasing year by year, and its pathogenesis is closely related to the intestinal flora. At present, the use of antibiotics is very common in the clinic. And cancer patients with low immunity are vulnerable to all sorts of infections, such as respiratory tract infections and urinary tract infections. Moreover, cancer patients easily run into fever and neutropenia induced by myelosuppression. Therefore, antibiotics are used extensively and even overused in many conditions. However, because of the special anatomical location of the gastrointestinal tract, the antibiotic usage will bring changes to the intestinal flora. Besides, with the expanding popularity of immunotherapy, various factors affecting the efficacy of immune checkpoint inhibitors (ICIs) have been extensively explored, including cancer-associated inflammation and the local and systemic factors that lead to immunosuppression. Some biomarkers for ICIs, including the expression of PD-L1, tumor mutation load, and microbiota, also have been investigated, and many studies have confirmed that gut microbiota can affect the efficacy of immunotherapy. But further studies on the influence of antibiotics directly on immunotherapy are rare. In this review, we discuss the relationship between GI tumors and antibiotics, the current status of immunotherapy in GI tumors, and the influence of antibiotics on immunotherapy.