Adoptive cellular immunotherapy for solid neoplasms beyond CAR-T.

In recent decades, immune checkpoint blockade and chimeric antigen receptor T cell (CAR-T) therapy are two milestone achievements in clinical immunotherapy. However, both show limited efficacies in most solid neoplasms, which necessitates the exploration of new immunotherapeutic modalities. The failure of CAR-T and immune checkpoint blockade in several solid neoplasms is attributed to multiple factors, including low antigenicity of tumor cells, low infiltration of effector T cells, and diverse mechanisms of immunosuppression in the tumor microenvironment. New adoptive cell therapies have been attempted for solid neoplasms, including TCR-T, CAR-natural killer cells (CAR-NK), and CAR-macrophages (CAR-M). Compared to CAR-T, these new adoptive cell therapies have certain advantages in treating solid neoplasms. In this review, we summarized the 40-year evolution of adoptive cell therapies, then focused on the advances of TCR-T, CAR-NK, and CAR-M in solid neoplasms and discussed their potential clinical applications.

Long-term Survival, Quality of Life, and Molecular Features of the Patients With Solid Pseudopapillary Neoplasm of the Pancreas: A Retrospective Study of 454 Cases.

OBJECTIVE: To present comprehensive information on the clinicopathological, molecular, survival characteristics, and quality of life (QOL) after surgery for solid pseudopapillary neoplasm (SPN) of the pancreas in a large cohort after long-term follow-up. BACKGROUND: SPN is a rare tumor with an uncertain malignant potential, and solid information on long-term prognosis and QOL remains limited. METHODS: All hospitalized patients with SPNs who underwent surgery between 2001 and 2021 at the Peking Union Medical College Hospital were retrospectively reviewed. The clinicopathological characteristics of the patients were retrieved. A cross-sectional telephone questionnaire was administered to inquire about the QOL. Molecular analyses were performed using whole-exome sequencing. RESULTS: Exactly 454 patients with SPN were enrolled, of whom 18.5% were males and 81.5% were females. The mean patient age was 31 ± 12 years. In total, 61.3% of the patients had no symptoms. The size of the tumors was 5.38 ± 3.70 cm; 83.4% were solid cystic tumors, and 40.1% had calcifications. The proportions of local resection, distal pancreatectomy with or without splenectomy, and pancreaticoduodenectomy with or without pylorus preservation were 29.7%, 28.9% or 22.9%, and 11% or 6.8%, respectively. Over the years, there has been a significant shift from open to minimally invasive surgery. Among all surgical procedures, pylorus-preserving pancreaticoduodenectomy (PPPD) had the highest incidence of grade 2 to 4 complications (up to 32.3%), compared with 6.7% in distal pancreatectomy ( P < 0.001). Regarding histopathology, tissue invasion, perineural invasion, cancerous microvascular emboli, lymph node metastasis, and distant metastasis were present in 16.5%, 2.2%, 0.7%, 2.0%, and 3.1% of patients, respectively. Sixty patients were lost to follow-up. Sixteen of the 390 patients who underwent resection (4.1%) experienced local recurrence or distant metastasis after surgery. In total, 361 patients responded to the telephone survey. Nearly 80% of patients claimed their QOL was not significantly affected after surgery; however, the remaining 20% complained of lower QOL during 3 to 6 years of follow-up after surgery. No clinicopathological factor could reliably predict clinical recurrence or metastasis after resection. A total of 28 driver genes were detected with mutations in at least 2 tumor samples and the top 3 frequently mutated genes were CTNNB1 , ATRNL1 , and MUC16 . CONCLUSIONS: This study presented the largest cohort of patients with SPN after surgery from a single center and reported the QOL of these patients. SPN is associated with extremely favorable long-term survival, even in patients with metastasis, and most patients have a good QOL after surgery.

Comparing the clinical value of baseline [68 Ga]Ga-FAPI-04 PET/CT and [18F]F-FDG PET/CT in pancreatic ductal adenocarcinoma: additional prognostic value of the distal pancreatitis.

PURPOSE: Anatomical and molecular staging strategies are needed for the personalized treatment of localized pancreatic ductal adenocarcinoma (PDAC). This study evaluated the performance of [68 Ga]Ga-FAPI-04 and [18F]F-FDG PET/CT on the disease staging and prognostic value of patients with localized PDAC on contrast-enhanced (CE)-CT images. METHODS: Patients with suspected localized PDAC on CE-CT were recruited for static [68 Ga]Ga-FAPI-04 and 18[F]F-FDG and PET/CT, and select patients underwent simultaneous 60-min dynamic 68 Ga-FAPI-04 PET/CT. The diagnostic and staging performances of the static PET/CT results were evaluated by delineating regions of interest in the primary tumor, whole pancreas, and distal pancreas in both types of scans and then evaluating correlations between the PET/CT findings and clinicopathological characteristics. Furthermore, Kaplan-Meier and hazard ratio (log-rank) methods were used to evaluate the prognostic value of the combined dynamic [68 Ga]Ga-FAPI-04 and static [18F]F-FDG PET/CT method. RESULTS: We included 49 patients with histologically confirmed PDAC adenocarcinomas; 32 underwent 60-min dynamic [68 Ga]Ga-FAPI-04 PET/CT imaging simultaneously. The static [68 Ga]Ga-FAPI-04 method had significantly higher accuracy and uptake values than the static [18F]F-FDG method for primary PDAC lesions, metastatic lymph nodes, and distal metastases. Furthermore, 18.4% and 10.2% of the patients' stages changed after using the [68 Ga]Ga-FAPI-04 and [18F]F-FDG PET/CT methodologies, respectively, compared to the CE-CT-designated stage. The Ki values obtained from dynamic [68 Ga]Ga-FAPI-04 PET/CT did not differ between PDAC and distal obstructive pancreatitis lesions. Pathologically enlarged tumor size, poor differentiation, and perineural invasion were associated with increased [68 Ga]Ga-FAPI-04 uptake but not with [18F]F-FDG uptake. The preoperative prognostic performance of [68 Ga]Ga-FAPI-04 was better than that of [18F]F-FDG. Interestingly, combined [68 Ga]Ga-FAPI-04 and [18F]F-FDG uptake results in the whole pancreas could further stratify patients based on their postoperative prognosis. CONCLUSION: 6[68 Ga]Ga-FAPI-04 PET/CT was more sensitive and accurate than [18F]F-FDG PET/CT for tumor, node, and metastasis staging of PDAC identified on CE-CT. Additionally, [68 Ga]Ga-FAPI-04 uptake was significantly associated with pathologically aggressive tumor features. Combined [68 Ga]Ga-FAPI-04 and [18F]F-FDG PET/CT findings improved the prognostic value, potentially providing a non-invasive guide for clinical management. Finally, increased fibroblast activity in PDAC-induced obstructive pancreatitis may be associated with poor patient survival rates.

Prognostic value of preoperative [68 Ga]Ga-FAPI-04 PET/CT in patients with resectable pancreatic ductal adenocarcinoma in correlation with immunohistological characteristics.

PURPOSE: Our aim was to assess the prognostic value of [68 Ga]Ga-FAPI-04 positron emission tomography (PET) uptake in PDAC and to evaluate the correlation between in vivo lesional radioactivity with pathological characteristics of pancreatic ductal adenocarcinoma (PDAC). METHODS: We retrospectively analyzed treatment-naïve PDAC patients who underwent preoperative [68 Ga]Ga-FAPI-04 PET/CT followed by pancreatectomy. The tracer uptake was determined as maximum tumor standardized uptake value (SUVmax), FAPI-avid tumor volume (FTV), total lesion FAP expression (TLF) as well total pancreatic uptake (TSUVmax), total FAPI-avid pancreatic volume (FPV), and total pancreatic FAP expression (TPF). Spearman's correlation analysis was performed to evaluate the association between [68 Ga]Ga-FAPI-04 PET/CT imaging and ex vivo immunohistological FAP expression and pathological characteristics of surgical specimens (differentiation, size, vascularity, perineural invasion, and lymph node metastases). Kaplan-Meier and hazard ratio (HR, log-rank) methods were used to evaluate the prognostic value of [68 Ga]Ga-FAPI-04 PET/CT and clinicopathological factors. RESULTS: Thirty-seven surgical PDAC patients were included. The ex vivo expression of FAP was significantly associated with the tumor SUVmax and TLF. FAP expression was more abundant in poorly differentiated PDAC than in well- to moderately differentiated neoplasms. Tumor SUVmax or TLF and pancreatic TSUVmax or TPF were significantly correlated with tumor size, differentiation, and perineural invasion, respectively. SUVmax had a significant independent prognostic value for recurrence-free survival (HR = 2.46, P < 0.05), while [68 Ga]Ga-FAPI-04 TPF predicted overall survival (HR = 12.82, P < 0.05). CONCLUSION: The in vivo [68 Ga]Ga-FAPI-04 uptake in localized PDAC showed a significant correlation with ex vivo FAP expression and aggressive pathological characteristics. [68 Ga]Ga-FAPI-04 PET/CT also presented a potential for postoperative prognostication of PDAC. Elevated fibroblast activity induced by obstructive pancreatitis might be associated with the patient's survival.

Identifying the preoperative factors predicting the surgical difficulty of robotic distal pancreatectomy.

BACKGROUND: Few studies have evaluated the preoperative factors predicting the surgical difficulty of robotic distal pancreatectomy (RDP). This study aims to explore such factors and provide guidance on the selection of suitable patients to aid surgeons lacking extensive experience in RDP. METHODS: A retrospective study was conducted on consecutive patients who underwent RDP to identify preoperative factors predicting surgical difficulty. High surgical difficulty was defined by both operation time and intraoperative estimated blood loss exceeding their median, or by conversion to laparotomy. RESULTS: A total of 161 patients were ultimately enrolled, including 51 patients with high levels of surgical difficulty. Multivariate analysis revealed that male sex [OR (95% CI): 4.07 (1.77,9.40), p = 0.001], body mass index (BMI) ≥ 25 kg/m2 OR (95% CI): 2.27 (1.03,5.00), p = 0.042], tumors located at the neck of the pancreas [OR (95% CI): 4.15 (1.49,11.56), p = 0.006] and splenic artery type B [OR (95% CI): 3.28 (1.09,9.91), p = 0.035] were independent risk factors for surgical difficulty. Regarding postoperative complications, high surgical difficulty was associated with the risk of overall complications and pancreatic fistula (grade B/C) (49.0% vs. 22.7%, p < 0.001; 39.2% vs. 19.1%, p = 0.006). CONCLUSION: Male sex, body mass index ≥ 25 kg/m2, tumor located at the neck of the pancreas and splenic artery type B are associated with a high RDP difficulty level. These factors can be used preoperatively to assess the difficulty level of surgery, to help surgeons choose patients suitable for them and ensure surgical safety.

Early Drain Removal is Safe in Patients With Low or Intermediate Risk of Pancreatic Fistula After Pancreaticoduodenectomy: A Multicenter, Randomized Controlled Trial.

OBJECTIVE: This multicenter randomized controlled trial was designed to test the hypothesis that early drain removal (EDR) could decrease the incidence of grade 2 to 4 complications for patients undoing pancreaticoduodenectomy (PD) with low or intermediate risk of postoperative pancreatic fistula (POPF). BACKGROUND: The safety and effects of EDR on postoperative complications after PD are still controversial. METHODS: A multicenter randomized controlled trial at 6 tertiary referral hospitals was carried out (NCT03055676). Patients who met the inclusion criteria, including drain amylase level less than 5000 U/L on postoperative day (POD) 1 and POD 3, and drain output less than 300 mL per day within 3 days after surgery, were enrolled. Patients were then randomized to the EDR group or the routine drain removal (RDR) group. In the EDR group, all drainage tubes were removed on POD3. In the RDR group, drainage tubes were removed on POD 5 or beyond. Primary outcome was the incidence of Clavien-Dindo grade 2 to 4 complications. Secondary outcomes were comprehensive complication index, grade B/C POPF, total medical expenses and postoperative in-hospital stay etc, within 90 days after surgery. RESULTS: A total of 692 patients were screened, and 312 patients were eligible for randomization. Baseline characteristics were well balanced between the 2 groups and 96.8% of these 312 patients had low or intermediate risk of POPF, according to the 10-point fistula risk score. A total of 20.5% of the patients in the EDR group suffered at least 1 grade 2 to 4 complication, versus 26.3% in the RDR group (P = 0.229). Multi-variate analysis showed older age (>65 years old) and blood transfusion were independent risk factors for grade 2 to 4 complications. The rate of grade B/C POPF was low in either group (3.8% vs 6.4%, P = 0.305). The comprehensive complication index of the 2 groups was also comparable (20.9 vs 20.9, P = 0.253). Total medical expenses were not significantly different. Postoperative in-hospital stay was clinically similar (15 days vs 16 days, P = 0.010). CONCLUSIONS: Nearly half of the patients undergoing PD met the inclusion criteria, predicting low incidence of grade B/C POPF and major complications. EDR was safe in these patients but did not significantly decrease major complications.

Dopamine improves chemotherapeutic efficacy for pancreatic cancer by regulating macrophage-derived inflammations.

Pancreatic cancer is an inflammatory malignancy, and tumor-associated macrophages (TAMs) are the predominant inflammatory cells in tumor tissue. TAMs have complicated interactions with pancreatic cancer cells, however, the details and mechanisms remain largely unknown. In this study, transcriptomics and proteomics analyses were performed to explore the interactions between murine pancreatic cancer cells and TAMs. Dopamine (DA) has been reported to suppress inflammations. However, its roles in TAMs of pancreatic cancer have not been reported. Herein, the roles and mechanisms of DA to affect the chemotherapeutic efficacy for pancreatic cancer were studied. Multi-omics results revealed that there was a tumor-promoting vicious cycle involving murine pancreatic cancer cells and TAMs. DA substantially improved the chemotherapeutic efficacy both in vitro study and in immunocompetent murine pancreatic cancer models by suppression of the M2 characters of TAMs. Further studies found that activation of DRD4 by DA led to the decrease of cAMP, and then inhibited the activation of PKA/p38 signal pathway, which suppressed the tumor-promoting inflammation of TAMs. This study uncovers the reciprocal interactions between TAMs and pancreatic cancer cells using multi-omics techniques and presents that DA has synergistic roles with chemotherapy for pancreatic cancer by suppressing of TAM-derived inflammations.

Upregulated CD58 is associated with clinicopathological characteristics and poor prognosis of patients with pancreatic ductal adenocarcinoma.

BACKGROUND: CD58 has been demonstrated to be abnormally expressed in multiple hematopoietic malignancies and solid tumors and plays an essential role in tumorigenesis and progression; however, its clinical significance and prognostic value in pancreatic ductal adenocarcinoma (PDAC) remain unknown. METHODS: Based on diverse online public databases and 81 PDAC samples of tissue microarray-based immunohistochemistry (IHC), we evaluated CD58 expression in PDAC patients and analyzed its association with clinicopathological characteristics, clinical outcomes, and infiltration of immune cells in PDAC. Furthermore, the correlation between CD58 and the cancer stem cell (CSC)-related, epithelial-mesenchymal transition (EMT)-related, and immune-related markers were detected. Besides, the functional enrichment analysis and related pathways were analyzed and visualized. RESULTS: CD58 expression was elevated in pancreatitis and PDAC tissues than normal pancreas or adjacent nontumor tissues. The positive cases of CD58 (e.g. more than 50% positive cells) in PDAC account for 95.06% (77/81). Upregulated CD58 in cancer tissues was associated with worse histological grade, larger tumor size, and poorer overall survival and disease-free survival in PDAC patients. Furthermore, Cox multivariate regression analysis revealed that CD58 was an independent prognostic factor in PDAC. CD58 expression was correlated with infiltrations of neutrophils, CD8+ T cells, and dendritic cells (DCs). In addition, correlation gene analysis indicated that CD58 expression was strongly correlated with immune-related, EMT-related, and CSC-related markers. Functional enrichment analysis and KEGG pathway manifested that CD58 might be involved in PDAC initiation and progression. CONCLUSIONS: CD58 expression is upregulated in PDAC tissues and its high expression is notably related to poor survival of PDAC. Therefore, CD58 may serve as a novel and effective marker for predicting the prognosis of PDAC patients.

Immune subtyping for pancreatic cancer with implication in clinical outcomes and improving immunotherapy.

BACKGROUND: Emerging evidence has shown that intra-tumor immune features are associated with response to immune checkpoint blockade (ICB) therapy. Accordingly, patient stratification is needed for identifying target patients and designing strategies to improve the efficacy of ICB therapy. We aimed to depict the specific immune features of patients with pancreatic cancer and explore the implication of immune diversity in prognostic prediction and individualized immunotherapy. METHODS: From transcriptional profiles of 383 tumor samples in TCGA, ICGC, and GEO database, robust immune subtypes which had different response immunotherapy, including ICB therapy, were identified by consensus clustering with five gene modules. DEGs analysis and tumor microarray were used to screen and demonstrate potential targets for improving ICB therapy. RESULTS: Three subtypes of pancreatic cancer, namely cluster 1-3 (C1-C3), characterized with distinct immune features and prognosis, were generated. Of that, subtype C1 was an immune-cold type in lack of immune regulators, subtype C2, with an immunosuppression-dominated phenotype characterized by robust TGFß signaling and stromal reaction, showed the worst prognosis, subtype C3 was an immune-hot type, with massive immune cell infiltration and in abundance of immune regulators. The disparity of immune features uncovered the discrepant applicability of anti-PD-1/PD-L1 therapy and potential sensitivity to other alternative immunotherapy for each subtype. Patients in C3 were more suitable for anti-PD-1/PD-L1 therapy, while patients in the other two clusters may need combined strategies targeted on other immune checkpoints or oncogenic pathways. A promising target for improving anti-PD-1/PD-L1 treatment, TGM2, was screened out and its role in the regulation of PD-L1 was investigated for the first time. CONCLUSION: Collectively, immune features of pancreatic cancer contribute to distinct immunosuppressive mechanisms that are responsible for individualized immunotherapy. Despite pancreatic cancer being considered as a poor immunogenic cancer type, the derived immune subtypes may have implications in tailored designing of immunotherapy for the patients. TGM2 has potential synergistic roles with ICB therapy.

Risk factors and prevention of postoperative pancreatic fistula after insulinoma enucleation:a retrospective study from a high-volume center.

BACKGROUND/OBJECTIVES: Enucleation is an effective surgical method to treat pancreatic insulinoma, however, the incidence of clinically relevant postoperative pancreatic fistula (CR-POPF) is high. We aim to investigate the risk factors for CR-POPF which have not been well characterized and develop effective methods to prevent CR-POPF after enucleation. METHODS: This retrospective cohort study included 161 patients diagnosed with insulinoma from June 2016 to July 2020 in Peking Union Medical College Hospital. The risk factors for CR-POPF were evaluated and the role of prophylactic pre-operative pancreatic stent to prevent the occurrence of CR-POPF after enucleation of pancreatic insulinoma were explored. RESULTS: A cohort of 161 insulinoma cases were reviewed. The CT or MRI imaging reports could be tracked in 108 cases. A total of 96 patients underwent surgery, while 81 experienced pancreatic enucleation. Univariate and multivariate analyses showed that the distance from insulinoma to the main pancreatic duct (MPD) ≤2 mm was an independent risk factor for CR-POPF (p = 0.003, OR = 6.011, 95% Cl 1.852-19.512). The pre-operative pancreatic stent substantially reduced the incidence of CR-POPF in patients with tumor located in proximity to (distance ≤2 mm) the MPD (CR-POPF of the stented group vs the non-stented group: 37.5% vs 71.4%, p = 0.028). CONCLUSIONS: The distance from insulinoma to MPD ≤2 mm is a predictive factor for CR-POPF after enucleation. Pancreatic duct stenting may benefit patients with insulinoma in proximity to the MPD by enabling a lower CR-POPF rate, so it should be considered before the enucleation of the insulinoma in proximity to the MPD (distance ≤2 mm).

Radical antegrade modular pancreatosplenectomy (RAMPS) versus conventional distal pancreatosplenectomy (CDPS) for left-sided pancreatic ductal adenocarcinoma.

PURPOSE: The insufficient clearance of regional lymph nodes and unsatisfactory R0 resection rate may result in the metastasis of left-sided pancreatic ductal adenocarcinoma (PDAC) after conventional distal pancreatosplenectomy (CDPS). Radical antegrade modular pancreatosplenectomy (RAMPS) was designed to achieve R0 resection more successfully with better lymph-node clearance; however, there is still insufficient evidence of its short- and long-term results to confirm its superiority. We conducted this study to compare the efficiency of these two procedures. METHODS: The subjects of this retrospective analysis were 103 patients with left-sided PDAC who underwent either RAMPS (n = 46) or CDPS (n = 57). We assessed perioperative data and surgical information and used univariate and multivariate analyses to identify prognostic factors for survival. RESULTS: There were no significant differences in baseline data between the groups. RAMPS was associated with a significantly shorter hospital stay (12.11 days vs. 22.98 days; P < 0.001), and significantly less blood loss (451.09 ml vs. 764.04 ml, P = 0.002), as well as a significantly lower rate of blood transfusion (15.22% vs. 33.33%, P = 0.035). RAMPS and CDPS had comparable perioperative complication rates. Moreover, RAMPS achieved more effective lymph-node retrieval (17.87 vs. 10.23; P < 0.001). The RAMPS group had a higher overall survival (OS) rate (28.73 months vs. 18.30 months; P = 0.003) and a higher disease-free survival (DFS) rate (21.97 months vs. 9.40 months; P < 0.001). CONCLUSION: RAMPS achieved better survival and surgical outcomes than CDPS for patients with left-sided PDAC.

Hypoglossal nerve palsy after gasless trans-axillary endoscopic thyroidectomy: a case report.

BACKGROUND: Gasless trans-axillary endoscopic thyroidectomy (GTAET) has satisfactory cosmetic effects for the patients who have benign goiter and small thyroid carcinoma, however the complications of this surgical procedure have not been fully documented. Ipsilateral hypoglossal nerve palsy (IHNP) associated with GTAET has never been reported before. CASE PRESENTATION: A 33-year old male patient presented with a 4 × 5 mm solid thyroid nodule in the right lobe. Papillary thyroid carcinoma was confirmed by the fine needle aspiration. He had strong cosmetic demand, therefore GTAET for right lobectomy and central cervical lymphadenectomy was performed in a supine position with cervical extension. Six hours after the operation, he developed tongue deviation to the right side, speech and swallowing difficulties, indicating IHNP. Head and cervical MRI showed no abnormality. The intravenous steroid was used for three days, and oral vitamin B1 and mecobalamin was prescribed for 1 month. Nine days after surgery, he was discharged. Three months after the operation, all the symptoms were completely resolved. CONCLUSIONS: To the best of the authors' knowledge, this is the first case of IHNP after GTAET, which will be valuable to add our knowledge to diagnose and treat rare complications of GTAET.

Up-regulation of CDHR5 expression promotes malignant phenotype of pancreatic ductal adenocarcinoma.

CDHR5 has been reported to play key roles in carcinogenesis of various cancers, but its roles in pancreatic cancer have not been reported. The present study was designed to investigate its clinical value in pancreatic ductal adenocarcinoma (PDAC). Tissue microarray-based immunohistochemistry was performed to analyse the correlation between CDHR5 expression and clinical and pathological features of PDAC, as well as the CDHR5 expression during tumour progression. Cell function assays were performed to investigate CDHR5's effects on PDAC cells. Moreover, qRT-PCR was applied to investigate the expression of CDHR5 isoforms in PDAC cells. Expression of CDHR5 was higher on the membrane of PDAC cells. This high expression level was associated with shorter overall survival of PDAC patients and was identified as an independent prognostic factor for overall survival by multivariate Cox regression analysis. In addition, expression level of CDHR5 presented an increased trend in the occurrence and progression of PDAC. Cell experiment suggested that CDHR5 could notably promote invasion and migration of PDAC cells. Moreover, analysis of CDHR5 isoforms indicated CDHR5-L was the major isoform expressed in PDAC cell lines. CDHR5 appears to be a promising and novel prognostic factor for PDAC, and its promotion in PDAC metastasis might be ascribed to the isoform CDHR5-L.

Combined blockade of TGf-ß1 and GM-CSF improves chemotherapeutic effects for pancreatic cancer by modulating tumor microenvironment.

The interactions between tumor immune microenvironment (TIME) and pancreatic cancer cells can affect chemotherapeutic efficacy; however, the mechanisms still remain largely unknown. Thirty items in TIME were comprehensively screened by using tissue microarray from pancreatic cancer patients. Their expressions, interconnections and predictive roles for survival were analyzed. Twenty-one of 30 items could stratify the survival of the patients; however, multivariate analysis found that only 5 independent risk factors could predict worse survival (M2-polarized tumor-associated macrophages (TAMs), IgG4 positive cells, TGF-ß1, GM-CSF and lymphangiogenesis). They had a much higher expression levels in tumoral tissue, compared to peritumoral tissue. The Spearman analysis showed that M2-polarized TAM, TGF-ß1 and GM-CSF were positively correlated with pancreatic cancer stem cells (PCSC), angiogenesis and lymphangiogenesis. Both human and murine pancreatic cancer cells could induce M2-polarized TAM, which showed substantial roles to decease chemotherapeutic effects. After treated by gemcitabine, both human and murine pancreatic cancer cell lines expressed higher level of immune check points, PCSC markers and varieties of immunosuppressive factors; however, TGF-ß1 and GM-CSF had the highest increase. Based on the above results, TGF-ß1 and GM-CSF were proposed to be the optimal potential targets to improve chemotherapeutic effects. In immunocompetent murine models, we demonstrated that combined blockade of TGF-ß1 and GM-CSF improved the chemotherapeutic effects by inhibition of M2-polarized TAM and induction of CD8 positive T cells. This study presents a novel promising combined strategy to improve the chemotherapeutic effects for pancreatic cancer.

Circular RNA and tumor microenvironment.

Circular RNAs (circRNAs) are small non-coding RNAs with a unique ring structure and play important roles as gene regulators. Disturbed expressions of circRNAs is closely related to varieties of pathological processes. The roles of circRNAs in cancers have gained increasing concerns. The communications between the cancer cells and tumor microenvironment (TME) play complicated roles to affect the malignant behaviors of cancers, which potentially present new therapeutic targets. Herein, we reviewed the roles of circRNAs in the TME.

Identification of prognosis-related genes and construction of multi-regulatory networks in pancreatic cancer microenvironment by bioinformatics analysis.

BACKGROUND: As one of the most lethal cancers, pancreatic cancer has been characterized by abundant supportive tumor-stromal cell microenvironment. Although the advent of tumor-targeted immune checkpoint blockers has brought light to patients with other cancers, its clinical efficacy in pancreatic cancer has been greatly limited due to the protective stroma. Thus, it is urgent to find potential new targets and establish multi-regulatory networks to predict patient prognosis and improve treatment. METHODS: We followed a strategy based on mining the Cancer Genome Atlas (TCGA) database and ESTIMATE algorithm to obtain the immune scores and stromal scores. Differentially expressed genes (DEGs) associated with poor overall survival of pancreatic cancer were screened from a TCGA cohort. By comparing global gene expression with high vs. low immune scores and subsequent Kaplan-Meier analysis, DEGs that significantly correlate with poor overall survival of pancreatic cancer in TCGA cohort were extracted. After constructing the protein-protein interaction network using STRING and limiting the genes within the above DEGs, we utilized RAID 2.0, TRRUST v2 database and degree and betweenness analysis to obtain non-coding RNA (ncRNA)-pivotal nodes and TF-pivotal nodes. Finally, multi-regulatory networks have been constructed and pivotal drugs with potential benefit for pancreatic cancer patients were obtained by screening in the DrugBank. RESULTS: In this study, we obtained 246 DEGs that significantly correlate with poor overall survival of pancreatic cancer in the TCGA cohort. With the advent of 38 ncRNA-pivotal nodes and 7 TF-pivotal nodes, the multi-factor regulatory networks were constructed based on the above pivotal nodes. Prognosis-related genes and factors such as HCAR3, PPY, RFWD2, WSPAR and Amcinonide were screened and investigated. CONCLUSION: The multi-regulatory networks constructed in this study are not only beneficial to improve treatment and evaluate patient prognosis with pancreatic cancer, but also favorable for implementing early diagnosis and personalized treatment. It is suggested that these factors may play an essential role in the progression of pancreatic cancer.

Correction to: Identification of prognosis-related genes and construction of multi-regulatory networks in pancreatic cancer microenvironment by bioinformatics analysis.

[This corrects the article DOI: 10.1186/s12935-020-01426-1.].

Laparoscopic assisted pancreaticoduodenectomy: an important link in the process of transition from open to total laparoscopic pancreaticoduodenectomy.

BACKGROUND: The safety of total laparoscopic pancreaticoduodenectomy still remains controversial. Laparoscopic assisted pancreaticoduodenectomy (LAPD) may be an alternative selection. The purpose of the present study is to compare a consecutive cohort of LAPD and open pancreaticoduodenectomy (OPD) from a single surgeon. METHODS: A comparison was conducted between LAPD and OPD from January 2013 to December 2018. Perioperative outcomes and short-term oncological results were compared. Univariate and multivariable analyses were performed to determine associations among variables. RESULTS: 133 patients were enrolled, 36 patients (27.1%) underwent LAPD and 97 (72.9%) underwent OPD. No 30-day and 90-day mortality occurred. LAPD was associated with decreased intraoperative estimated blood loss (300 versus 500 ml; P = 0.002), longer operative time (372 versus 305 min; P < 0.001) compared with OPD. LAPD had a conversion rate of 16.7%, and wasn't associated with an increased grade B/C pancreatic fistula rate, major surgical complications, intraoperative blood transfusion, reoperation rate or length of hospital stay after surgery. In the subset of 58 pancreatic ductal adenocarcinomas, R0 resection rate, median total harvested lymph node or lymph nodes ≥12 did not differ between the two groups. CONCLUSION: LAPD could be performed with non-inferior short-term perioperative and oncologic outcomes achieved by OPD in selected patients.

Dynamic hematological changes in patients undergoing distal pancreatectomy with or without splenectomy: a population-based cohort study.

BACKGROUND: The clinical outcomes of patients who received distal pancreatectomy with splenectomy (DPS) and spleen-preserving distal pancreatectomy (SPDP) have been generally investigated. However, postoperative hematological changes after distal pancreatectomy with or without splenectomy are poorly understood. METHODS: Information from patients undergoing distal pancreatectomy (DP) between January 2014 and June 2019 at a single institution was reviewed. A linear mixed-effects model was used to compare dynamic hematological changes between different groups. RESULTS: A total of 302 patients who underwent DP were enrolled. In the long term, most postoperative hematological parameters remained significantly higher than preoperative levels in the DPS group, while postoperative lymphocyte, monocyte, basophil, and platelet levels returned to preoperative levels in the SPDP group. All postoperative hematological parameters except for red blood cell count and serum hemoglobulin level were significantly higher in the DPS group than in the SPDP group. There were no significant differences in hematological changes between the splenic vessel preservation (SVP) and Warshaw technique (WT) groups. CONCLUSIONS: Postoperative hematological changes were significantly different between the DPS and SPDP groups. Compared to DPS, SPDP reduced abnormal hematological changes caused by splenectomy. SVP and WT were comparable in terms of postoperative hematological changes.

Role of the complement system in the tumor microenvironment.

The complement system has traditionally been considered a component of innate immunity against invading pathogens and "nonself" cells. Recent studies have demonstrated the immunoregulatory functions of complement activation in the tumor microenvironment (TME). The TME plays crucial roles in tumorigenesis, progression, metastasis and recurrence. Imbalanced complement activation and the deposition of complement proteins have been demonstrated in many types of tumors. Plasma proteins, receptors, and regulators of complement activation regulate several biological functions of stromal cells in the TME and promote the malignant biological properties of tumors. Interactions between the complement system and cancer cells contribute to the proliferation, epithelial-mesenchymal transition, migration and invasion of tumor cells. In this review, we summarize recent advances related to the function of the complement system in the TME and discuss the therapeutic potential of targeting complement-mediated immunoregulation in cancer immunotherapy.