N6-methyladenosine-modified VGLL1 promotes ovarian cancer metastasis through high-mobility group AT-hook 1/Wnt/β-catenin signaling

The main causes of death in patients with ovarian cancer (OC) are invasive lesions and the spread of metastasis. The present study aimed to explore the mechanisms that might promote OC metastasis. Here, we identified that VGLL1 expression was remarkably increased in metastatic OC samples. The role of VGLL1 in OC metastasis and tumor growth was examined by cell function assays and mouse models. Mechanistically level, METTL3-mediated N6-methyladenosine (m6A) modification contributed to VGLL1 upregulation in an IGF2BP2 recognition-dependent manner. Furthermore, VGLL1 directly interacts with TEAD4 and co-transcriptionally activates HMGA1. HMGA1 further activates Wnt/β-catenin signaling to enhance OC metastasis by promoting the epithelial-mesenchyme transition traits. Rescue assays indicated that the upregulation of HMGA1 was essential for VGLL1-induced metastasis. Collectively, these findings showed that the m6A-induced VGLL1/HMGA1/β-catenin axis might play a vital role in OC metastasis and tumor growth. VGLL1 might serve as a prognostic marker and therapeutic target against the metastasis of OC.

Surufatinib plus toripalimab in patients with advanced neuroendocrine tumours and neuroendocrine carcinomas: An open-label, single-arm, multi-cohort phase II trial

BACKGROUND

The programmed death 1 inhibitor toripalimab plus the angio-immuno kinase inhibitor surufatinib revealed a tolerable safety profile and preliminary efficacy in patients with advanced solid tumours in a phase I study.

PATIENTS AND METHODS

This was an open-label, single-arm, multi-cohort phase II study in China. Patients with advanced neuroendocrine tumours (NETs) or neuroendocrine carcinomas (NECs) or mixed neuroendocrine non-neuroendocrine neoplasms (MiNENs) who had failed or were intolerable of standard treatment were given surufatinib (250 mg orally, once daily) plus toripalimab (240 mg intravenously, once every 3 weeks). Primary end-point was investigator-assessed objective response rate (ORR) per Response Evaluation Criteria in Solid Tumors version 1.1. Secondary end-points included duration of response (DoR), disease control rate, progression-free survival (PFS), overall survival (OS), and safety.

RESULTS

Forty patients were enrolled into two cohorts by tumour types (NET, n = 19; NEC-MiNEN, n = 21). ORRs (95% CIs) were 21.1% (6.1-45.6) and 23.8% (8.2-47.2) in the NET and NEC-MiNEN cohorts, respectively. Median DoR was 7.1 months (6.9-not evaluable [NE]) and 4.1 months (3.0-NE), respectively. Median PFS was 9.6 months (4.1-NE) and 4.1 months (1.5-5.5); median OS was 27.3 (15.3-NE) and 10.9 months (9.1-14.6), respectively. Overall, grade ≥ 3 treatment-related adverse events occurred in 18 (45.0%) patients.

CONCLUSIONS

Surufatinib plus toripalimab showed antitumour activity and a tolerable safety profile in patients with previously treated NETs/NECs/MiNENs. Further study of this combination regimen is ongoing for advanced NECs, for which current therapeutic options remain limited.

CLINICALTRIALS

gov: NCT04169672.

Adaptive Radiotherapy Guided by PET/CT in Patients with Locally Advanced Non-Small Cell Lung Cancer: A Phase II Randomized Study

PURPOSE/OBJECTIVE(S)

The aim of this study was to determine whether adaptive radiotherapy guided by functional imaging with flourine-18 fluorodeoxyglucose positron emission tomography/computed tomography (18F-FDG PET/CT) can improve local tumor control in patients with locally advanced non-small cell lung cancer (LA-NSCLC).

MATERIALS/METHODS

This was a phase II randomized study comparing the efficacy and safety between PET-guided adaptive radiotherapy and conventional radiotherapy. The primary end point was 2-year local-regional tumor control (LRTC) rate. Secondary end points included local-regional progression-free survival (LR-PFS), progression-free survival (PFS), overall survival (OS), and radiation-related toxicities.

RESULTS

Between November 2012 and June 2017, 72 patients were 1:1 randomized to adaptive and conventional arms. The 2- and 5-year LRTC rates were 63.2% and 58.0% versus 43.0% and 37.6% (P = 0.035) in the adaptive and conventional arms, respectively. The median LR-PFS (14.3 versus 12.0 months; P = 0.010) and PFS (12.8 versus 8.9 months; P = 0.034) were significantly longer in the adaptive arm than in the conventional arm. The median OS was 36.3 months in the adaptive arm and 28.8 months in the conventional arm (P = 0.266). The esophageal volume of receiving ≥60 Gy (V60) in the adaptive arm was lower than that in the conventional arm (P = 0.011), while the V30 for the heart in the adaptive arm was lower than that in the conventional arm (P = 0.077). Other radiological metrological parameters of tumor, organs at risk, and the incidence of ≥grade 2 radiation-related toxicities were not significantly different between the 2 arms.

CONCLUSION

Compared with conventional radiotherapy, PET-guided adaptive radiotherapy significantly improved the 2-year LRTC rate, LR-PFS, and PFS without increased risks of radiation-related toxicities in patients with LA-NSCLC.

Anlotinib as a maintenance treatment for advanced soft tissue sarcoma after first-line chemotherapy (ALTER-S006): a multicentre, open-label, single-arm, phase 2 trial

Background

No standard maintenance treatment has been obtained to prolong the response duration of soft tissue sarcoma (STS) after first-line chemotherapy. In this study, we aimed to evaluate the efficacy and safety of anlotinib as a maintenance treatment after chemotherapy in STS.

Methods

In this multicentre, open-label, single-arm phase 2 trial, patients with advanced STS who achieved partial response or stable disease after first-line anthracycline-based chemotherapy were enrolled between April 2019 and January 2022. All patients received anlotinib as a maintenance treatment. The primary endpoint was progression-free survival (PFS) of anlotinib maintenance treatment. Other endpoints included overall survival (OS), objective response rate (ORR), disease control rate (DCR) and safety. This study is registered with ClinicalTrials.gov, NCT03890068.

Findings

At the data cut-off date (August 8, 2022), 49 patients were enrolled, including 17 with liposarcoma (35%) and 15 with leiomyosarcoma (31%). After a median follow-up of 17.1 months (IQR 9.0-27.2), the median PFS from the beginning of maintenance treatment was 9.1 months (95% CI 5.7-12.5), and the median OS was not reached, and the 1-year OS rate for anlotinib maintenance treatment was 98.0%. The best ORR and DCR were 16% (8/49, 95% CI 7-30) and 94% (46/49, 95% CI 83-99), respectively. Most of the treatment-related adverse events were grade 1-2. Of the grade 3-4 adverse events, the most common were hypertension (10%) and hand-foot syndrome reaction (6%).

Interpretation

Postchemotherapy maintenance treatment with anlotinib exhibits promising efficacy and tolerable toxicity in patients with advanced STS.

Funding

Chia Tai Tianqing Pharmaceutical Group Co., Ltd., the National Key Research and Development Program of China, and the National Natural Science Foundation of China.

Targeted delivery of a PD-1-blocking scFv by CD133-specific CAR-T cells using nonviral Sleeping Beauty transposition shows enhanced antitumour efficacy for advanced hepatocellular carcinoma

BACKGROUND

CD133 is considered a marker for cancer stem cells (CSCs) in several types of tumours, including hepatocellular carcinoma (HCC). Chimeric antigen receptor-specific T (CAR-T) cells targeting CD133-positive CSCs have emerged as a tool for the clinical treatment of HCC, but immunogenicity, the high cost of clinical-grade recombinant viral vectors and potential insertional mutagenesis limit their clinical application.

METHODS

CD133-specific CAR-T cells secreting PD-1 blocking scFv (CD133 CAR-T and PD-1 s cells) were constructed using a sleeping beauty transposon system from minicircle technology, and the antitumour efficacy of CD133 CAR-T and PD-1 s cells was analysed in vitro and in vivo.

RESULTS

A univariate analysis showed that CD133 expression in male patients at the late stage (II and III) was significantly associated with worse progression-free survival (PFS) (P = 0.0057) and overall survival (OS) (P = 0.015), and a multivariate analysis showed a trend toward worse OS (P = 0.041). Male patients with advanced HCC exhibited an approximately 20-fold higher PD-L1 combined positive score (CPS) compared with those with HCC at an early stage. We successfully generated CD133 CAR-T and PD-1 s cells that could secrete PD-1 blocking scFv based on a sleeping beauty system involving minicircle vectors. CD133 CAR-T and PD-1 s cells exhibited significant antitumour activity against HCC in vitro and in xenograft mouse models. Thus, CD133 CAR-T and PD-1 s cells may be a therapeutically tractable strategy for targeting CD133-positive CSCs in male patients with advanced HCC.

CONCLUSIONS

Our study provides a nonviral strategy for constructing CAR-T cells that could also secrete checkpoint blockade inhibitors based on a Sleeping Beauty system from minicircle vectors and revealed a potential benefit of this strategy for male patients with advanced HCC and high CD133 expression (median immunohistochemistry score > 2.284).

Phase 1 clinical trial to assess safety and efficacy of NY-ESO-1-specific TCR T cells in HLA-A∗02:01 patients with advanced soft tissue sarcoma

New York esophageal squamous cell carcinoma-1 (NY-ESO-1)-specific T cell receptor (TCR) T cell therapy is effective in tumors with NY-ESO-1 expression, but a safe and effective TCR-T cell therapeutic protocol remains to be improved. Here, we report a phase 1 investigational new drug clinical trial with TCR affinity-enhanced specific T cell therapy (TAEST16001) for targeting NY-ESO-1. Enrolled patients receive TAEST16001 cell infusion after dose-reduced lymphodepletion with cyclophosphamide (15 mg/kg/day × 3 days) combined with fludarabine (20 mg/m2/day × 3 days), and the TCR-T cells are maintained with low doses of interleukin-2 injection post-adoptive transfer. Analysis of 12 patients treated with the regimen demonstrates no treatment-related serious adverse events. The overall response rate is 41.7%. The median progression-free survival is 7.2 months, and the median duration of response is 13.1 months. The protocol of TAEST16001 cells delivers a safe and highly effective treatment for patients with advanced soft tissue sarcoma (ClinicalTrials.gov: NCT04318964).

Lenvatinib improves anti-PD-1 therapeutic efficacy by promoting vascular normalization via the NRP-1-PDGFRβ complex in hepatocellular carcinoma

Introduction

The limited response to immune checkpoint blockades (ICBs) in patients with hepatocellular carcinoma (HCC) highlights the urgent need for broadening the scope of current immunotherapy approaches. Lenvatinib has been shown a potential synergistic effect with ICBs. This study investigated the optimal method for combining these two therapeutic agents and the underlying mechanisms.

Methods

The effect of lenvatinib at three different doses on promoting tissue perfusion and vascular normalization was evaluated in both immunodeficient and immunocompetent mouse models. The underlying mechanisms were investigated by analyzing the vascular morphology of endothelial cells and pericytes. The enhanced immune infiltration of optimal-dose lenvatinib and its synergistic effect of lenvatinib and anti-PD-1 antibody was further evaluated by flow cytometry and immunofluorescence imaging.

Results

There was an optimal dose that superiorly normalized tumor vasculature and increased immune cell infiltration in both immunodeficient and immunocompetent mouse models. An adequate concentration of lenvatinib strengthened the integrity of human umbilical vein endothelial cells by inducing the formation of the NRP-1-PDGFRβ complex and activating the Crkl-C3G-Rap1 signaling pathway in endothelial cells. Additionally, it promoted the interaction between endothelial cells and pericytes by inducing tyrosine-phosphorylation in pericytes. Furthermore, the combination of an optimal dose of lenvatinib and an anti-PD-1 antibody robustly suppressed tumor growth.

Conclusions

Our study proposes a mechanism that explains how the optimal dose of lenvatinib induces vascular normalization and confirms its enhanced synergistic effect with ICBs.

A Novel Heat Shock Protein 70-Based Vaccine Prepared from DC Tumor Fusion Cells: An Update

We have developed an enhanced molecular chaperone-based vaccine through rapid isolation of Hsp70 peptide complexes after the fusion of tumor and dendritic cells (Hsp70.PC-F). In this approach, the tumor antigens are introduced into the antigen-processing machinery of dendritic cells through the cell fusion process, and thus we can obtain antigenic tumor peptides or their intermediates that have been processed by dendritic cells. Our results show that Hsp70.PC-F has increased immunogenicity compared to preparations from tumor cells alone and therefore constitutes an improved formulation of the chaperone protein-based tumor vaccine.

Alarmin IL-33 orchestrates antitumoral T cell responses to enhance sensitivity to 5-fluorouracil in colorectal cancer

Rationale: Resistance to 5-fluorouracil (5-FU) chemotherapy remains the main barrier to effective clinical outcomes for patients with colorectal cancer (CRC). A better understanding of the detailed mechanisms underlying 5-FU resistance is needed to increase survival. Interleukin (IL)-33 is a newly discovered alarmin-like molecule that exerts pro- and anti-tumorigenic effects in various cancers. However, the precise role of IL-33 in CRC progression, as well as in the development of 5-FU resistance, remains unclear. Methods: High-quality RNA-sequencing analyses were performed on matched samples from patients with 5-FU-sensitive and 5-FU-resistant CRC. The clinical and biological significance of IL-33, including its effects on both T cells and tumor cells, as well as its relationship with 5-FU chemotherapeutic activity were examined in ex vivo, in vitro and in vivo models of CRC. The molecular mechanisms underlying these processes were explored. Results: IL-33 expressed by tumor cells was a dominant mediator of antitumoral immunity in 5-FU-sensitive patients with CRC. By binding to its ST2 receptor, IL-33 triggered CD4+ (Th1 and Th2) and CD8+ T cell responses by activating annexin A1 downstream signaling cascades. Mechanistically, IL-33 enhanced the sensitivity of CRC cells to 5-FU only in the presence of T cells, which led to the activation of both tumor cell-intrinsic apoptotic and immune killing-related signals, thereby synergizing with 5-FU to induce apoptosis of CRC cells. Moreover, injured CRC cells released more IL-33 and the T cell chemokines CXCL10 and CXCL13, forming a positive feedback loop to further augment T cell responses. Conclusions: Our results identified a previously unrecognized connection between IL-33 and enhanced sensitivity to 5-FU. IL-33 created an immune-active tumor microenvironment by orchestrating antitumoral T cell responses. Thus, IL-33 is a potential predictive biomarker for 5-FU chemosensitivity and favorable prognosis and has potential as a promising adjuvant immunotherapy to improve the clinical benefits of 5-FU-based therapies in the treatment of CRC.

OTUD4-mediated GSDME deubiquitination enhances radiosensitivity in nasopharyngeal carcinoma by inducing pyroptosis

BACKGROUND

Radioresistance is the primary cause of nasopharyngeal carcinoma (NPC) treatment failure. Previous studies have focused on the deficits in cellular apoptosis as a mechanism for radioresistance; however, additional potential death modes involved in modulating radiosensitivity of NPC have not been explored.

METHODS

Pyroptosis was assessed by phase-contrast imaging, LDH release assays, live cell imaging, and Western blotting. In vitro and in vivo assays were used to investigate the function of gasdermin E (GSDME) and ovarian tumor family deubiquitinase 4 (OTUD4). NPC tissues were analyzed using Western blotting, immunohistochemistry, and real-time PCR. The molecular mechanism was determined using immunoprecipitation assays and mass spectrometry.

RESULTS

Live cell imaging revealed that 40-75% of irradiation-induced dead NPC cells were pyroptotic cells. Furthermore, irradiation-induced pyroptosis is triggered by GSDME, which are cleaved by activated caspase-3 in the intrinsic mitochondrial pathway. Additionally, GSDME was significantly downregulated in radioresistant NPC specimens. Low GSDME expression was a predictor of worse prognosis and conferred NPC radioresistance both in vitro and in vivo. Mechanistically, OTUD4 deubiquitinated and stabilized GSDME, enhancing radiosensitivity of NPC cells by promoting pyroptosis. Clinically, OTUD4 was significantly correlated with GSDME in NPC biopsies, and patients with low expression of both OTUD4 and GSDME suffered the worst radiotherapy response and survival.

CONCLUSIONS

GSDME-dependent pyroptosis is a critical determinant of radiosensitivity in NPC, and is modulated by OTUD4 via deubiquitinating and stabilizing GSDME. These findings reveal a promising novel direction to investigate radioresistance and suggest potential therapeutic targets for sensitizing NPC to radiotherapy.

Adjuvant alternative cytokine-induced killer cell combined with natural killer cell immunotherapy improves the prognosis of post-mastectomy breast cancer

Breast cancer is one of the most common cancers in women. Triple-negative breast cancer (TNBC) has a significantly worse prognosis due to the lack of endocrine receptors including estrogen receptor (ER), progesterone receptor (PR) and human epidermal growth factor receptor 2 (HER2). In this study, we investigated adjuvant cellular immunotherapy (CIT) in patients with post-mastectomy breast cancer. We enrolled 214 post-mastectomy breast cancer patients, including 107 patients in the control group (who received chemotherapy/radiotherapy/endocrine therapy) and the other 107 patients in the CIT group (who received chemotherapy/radiotherapy/endocrine therapy and subsequent immune cell infusion). Of these 214 patients, 54 had TNBC, including 26 patients in the control group and 28 patients in the CIT group. Survival analysis showed that the overall survival rate of patients treated with cellular immunotherapy was higher than that of patients who were not treated with CIT. Compared to those who received cytokine-induced killer (CIK) cells alone, the patients who received CIK combined with natural killer (NK) cell immunotherapy showed the best overall survival rate. In subgroup analyses, adjuvant CIT significantly improved the overall survival of patients in the TNBC subgroup and the patients who were aged over 50 years. Our study indicates that adjuvant CIK cell combined with NK cell treatment is an effective therapeutic strategy to prolong the survival of post-mastectomy patients, particularly for TNBC patients and those who are aged over 50 years.

Phase I clinical trial to assess safety, pharmacokinetics (PK), pharmacodynamics (PD), and efficacy of NY-ESO-1–specific TCR T-cells (TAEST16001) in HLA-A*02:01 patients with advanced soft tissue sarcoma

11502

Background: NY-ESO-1 is a cancer/testis antigen with expression in a wide range of tumor types. TAEST16001 cells are genetically engineered autologous T cells that express high-affinity NY-ESO-1-specific T-cell receptor (TCR) targeting NY-ESO-1+ soft tissue sarcoma in the context of HLA-A*02:01. Here, we report preliminary results of TAEST16001 cells from an ongoing, dose-escalation and expansion study in HLA-A*02:01 positive patients with advanced soft tissue sarcoma expressing NY-ESO-1 antigen. Methods: This is an open, single arm, dose-escalation and expansion study to evaluate safety, tolerability, PK, PD and preliminary efficacy of TAEST16001 cells in patients with soft tissue sarcoma. Enrolled patients underwent apheresis, and their isolated T cells were expanded in vitro after transducing with a lentiviral vector containing NY-ESO-1 TCR. Prior to TAEST16001 cells infusion, patients were to receive lymphodepleting chemotherapy consisting of cyclophosphamide (15 mg/kg/day ´ 3 days) and fludarabine (20 mg/m2/day ´ 3 days). TAEST16001 cells were administered at 5 × 108 ± 30% (dose level 1), 2 × 109 ± 30% (dose level 2), 5 × 109 ± 30% (dose level 3) and 1.2 × 1010 ± 30% (dose level 4/expansion) transduced cells. After TAEST16001 cells infusion, patients were to receive interleukin-2 subcutaneous injection for 14 days. Tumor responses were assessed by RECIST/iRECIST. Results: As of 31 December 2021, 12 patients with advanced soft tissue sarcoma were enrolled (M:F 7:5; mean age = 37.9; median prior regimens = 2 (range 1-3)). TAEST16001 cells were well-tolerated with no dose limiting toxicity. The most frequently reported grade ³ 3 adverse events were lymphopenia (n = 12), leukopenia (n = 10), neutropenia (n = 11), anemia (n = 4), thrombocytopenia (n = 1), hypokalemia (n = 1), and fever (n = 1). Two patients presented with cytokine release syndrome (grades 2) and resolved after symptomatic treatment. None of the patients had neurotoxicity, or serious adverse events related to cell infusion. The maximum tolerated dose (MTD) was not reached. PK modelling indicated that Tmax of TAEST16001 cells were 6.23 days after cells infusion, and there were no relationship between clinical response and Cmax/AUC0-28. Among 12 efficacy-evaluable patients, 5 patients had a partial response, 5 patients had stable disease, and 2 patients had progressive disease. The overall response rate was 41.7%. The median time to an initial response was 1.9 month (range, 0.9 to 3.0), and the median duration of response was 14.1 months (range, 5.0 to 14.2). Conclusions: TAEST16001 cells showed an acceptable tolerability profile overall. MTD was not reached. Emerging efficacy data encouraged the continued expansion study of TAEST16001 cells in advanced soft tissue sarcoma. Clinical trial information: NCT04318964.

CircITGB6 promotes ovarian cancer cisplatin resistance by resetting tumor-associated macrophage polarization toward the M2 phenotype

Background

Platinum resistance is a major challenge in the clinical treatment of advanced ovarian cancer (OC). Accumulating evidence shows that the tumor-promotive M2 macrophage is linked to the limiting chemotherapy efficacy of multiple malignancies including OC. Circular RNAs (circRNAs) are a novel class of non-coding RNAs which function as the critical regulator in biological process of cancer. However, their impact on macrophage polarization and chemoresistance of OC remain unclear.

Methods

Platinum-resistant circRNAs were screened using circRNA deep sequencing and validated using in situ hybridization in OC tissues with or without platinum resistance. The role of circITGB6 in inducing cisplatin (CDDP) resistance was evaluated by clone formation, immunofluorescence and annexin V assays in vitro, and by intraperitoneal tumor model in vivo. The mechanism underlying circITGB6-mediated tumor-associated macrophage (TAM) polarization into M2 phenotype was investigated using RNA pull-down, luciferase reporter, electrophoretic mobility shift, RNA binding protein immunoprecipitation (RIP), ELISA and immunofluorescence assays.

Results

We identified that a novel circRNA, circITGB6, robustly elevated in tumor tissues and serums from patients with OC with platinum resistance, was correlated with poor prognosis. circITGB6 overexpression promoted an M2 macrophage-dependent CDDP resistance in both vivo and vitro. Mechanistic research determined that circITGB6 directly interacted with IGF2BP2 and FGF9 mRNA to form a circITGB6/IGF2BP2/FGF9 RNA–protein ternary complex in the cytoplasm, thereby stabilizing FGF9 mRNA and inducing polarization of TAMs toward M2 phenotype. Importantly, blocking M2 macrophage polarization with an antisense oligonucleotide targeting circITGB6 markedly reversed the circITGB6-induced CDDP resistance of OC in vivo.

Conclusions

This study reveals a novel mechanism for platinum resistance in OC and demonstrates that circITGB6 may serve as a potential prognostic marker and a therapeutic target for patients with OC.

CMTM6 inhibits tumor growth and reverses chemoresistance by preventing ubiquitination of p21 in hepatocellular carcinoma

Hepatocellular carcinoma is one of the most common malignancies and has a poor prognosis. The ubiquitin-proteasome pathway is required for the degradation of most short-lived proteins. CMTM6 has been implicated in the progression of various tumors, but its biological function and the underlying molecular mechanisms in HCC are still unknown. In this study, we found that the expression of CMTM6 was significantly reduced in HCC and predicted better prognosis of HCC patients. Through in vitro and in vivo experiments, CMTM6 was shown to inhibit the proliferation of HCC cells by blocking the G1/S phase transition. Mechanistically, CMTM6 interacted with p21 and prevented its ubiquitination mediated by SCFSKP2, CRL4CDT2 and APC/CCDC20 in a cell-cycle–independent manner. As a result, CMTM6 stabilized p21 protein, leading to the inactivation of pRB/E2F pathway. Additionally, CMTM6 sensitized HCC cells to doxorubicin and cisplatin, positively correlated with better clinical outcomes of the transarterial chemoembolization (TACE) treatment for postoperative recurrence. Taken together, our study reports a novel mechanism by which p21 can be stabilized by CMTM6 and pinpoints a crucial role of the CMTM6-p21 axis in suppressing the progression of HCC and sensitizing patients with postoperative recurrence to TACE treatment.

Inhibition of DTYMK significantly restrains the growth of HCC and increases sensitivity to oxaliplatin

Most patients with hepatocellular carcinoma (HCC) are in the middle or advanced stage at the time of diagnosis, and the therapeutic effect is limited. Therefore, this study aimed to verify whether deoxythymidylate kinase (DTYMK) increased in HCC and was an effective therapeutic target in HCC. The findings revealed that the DTYMK level significantly increased and correlated with poor prognosis in HCC. However, nothing else is known, except that DTYMK could catalyze the phosphorylation of deoxythymidine monophosphate (dTMP) to form deoxythymidine diphosphate (dTDP). A number of experiments were performed to study the function of DTYMK in vitro and in vivo to resolve this knowledge gap. The knockdown of DTYMK was found to significantly inhibit the growth of HCC and increase the sensitivity to oxaliplatin, which is commonly used in HCC treatment. Moreover, DTYMK was found to competitively combine with miR-378a-3p to maintain the expression of MAPK activated protein kinase 2 (MAPKAPK2) and thus activate the phospho-heat shock protein 27 (phospho-HSP27)/nuclear factor NF-kappaB (NF-κB) axis, which mediated the drug resistance, proliferation of tumor cells, and infiltration of tumor-associated macrophages by inducing the expression of C-C motif chemokine ligand 5 (CCL5). Thus, this study demonstrated a new mechanism and provided a new insight into the role of mRNA in not only encoding proteins to regulate the process of life but also regulating the expression of other genes and tumor microenvironment through the competing endogenous RNA (ceRNA) mechanism.

Phase II trial of surufatinib plus toripalimab for disease progression after first-line chemotherapy with platinum and fluoropyrimidine in advanced gastric or gastroesophageal junction adenocarcinoma

e16040

Background: Surufatinib is a novel small-molecule kinase inhibitor targeting VEGFRs, FGFR and CSF-1R, simultaneous targeting of angiogenesis through VEGFRs/FGFR1 and modulating tumor immune microenvironment through CSF-1R may be a uniquely potent strategy to enhance antitumor activity. Toripalimab is a monoclonal humanized IgG4 PD-1 antibody. Encouraging efficacy of surufatinib plus toripalimab treating patients with advanced solid tumors was reported at 2020 AACR. This is an ongoing, multicenter, open-label, single-arm, phase II study to evaluate the efficacy and safety of surufatinib in combination with toripalimab in various solid tumors. Here we report the results of patients with advanced gastric or gastroesophageal junction (GEJ) adenocarcinoma. Methods: Patients with histologically confirmed gastric or GEJ adenocarcinoma who have failed first-line of systemic chemotherapy were enrolled. Surufatinib 250 mg once a day (QD) will be orally administrated and toripalimab 240 mg will be intravenously administered every 3 weeks. Primary endpoint was the objective response rate (ORR) per RECIST v1.1. Results: As of Dec 31, 2020, a total of 21 gastric or GEJ adenocarcinoma patients were enrolled. The median age was 58 years old, and 81% of the patients were male. Median duration of treatment was 3 months (surufatinib, 3 months; toripalimab, 3 months). Among 15 patients with at least one post-baseline efficacy evaluation, 2 patients achieved confirmed partial response (PR), with 3 additional unconfirmed PR. And there were 6 in stable disease (SD), 3 in progressive disease (PD) and one not evaluable per RECIST v1.1. There were 5 in PR, 7 in SD and 2 in PD per irRECIST, respectively. The confirmed and unconfirmed ORR were 13.3% (95% CI: 1.7%-40.5%) and 33.3% (95% CI: 11.8%-61.6%), respectively. The disease control rate (DCR) was 73.3% (95% CI: 44.9%-92.2%) per RECIST v1.1. Median PFS was 3.71 months (95% CI: 1.41-unknown). 14.3% (3/21) of patients had treatment-related adverse events (TRAEs) of ≥ Grade 3. The most common TRAEs of ≥ Grade 3 were herpes zoster (4.8%), lymphopenia (4.8%), lymphocyte count decreased (4.8%), white blood cell count decreased (4.8%), liver injury (4.8%) and anaemia (4.8%). 4.8% (1/21) of patients had serious TRAEs. One patient died due to unknown reasons. Conclusions: Surufatinib plus toripalimab appeared to show encouraging activity in advanced gastric or GEJ adenocarcinoma with manageable safety profile. Such combination could be a promising strategy for advanced gastric or GEJ adenocarcinoma in the future. Clinical trial information: NCT04169672.

Surufatinib in combination with toripalimab in patients with advanced neuroendocrine carcinoma: Results from a multicenter, open-label, single-arm, phase II trial

e16199

Background: Patients with advanced neuroendocrine carcinoma (NEC) have a poor prognosis and limited treatment option after first-line treatment. Surufatinib, a multi-kinase inhibitor of VEGFR 1-3, FGFR 1 and CSF-1R, has been approved in patients with advanced or metastatic extra-pancreatic neuroendocrine tumors in China. Toripalimab is a monoclonal humanized IgG4 PD-1 antibody. Surufatinib modulates tumor immune microenvironment and has shown promising antitumor activity in combination with toripalimab in solid tumors, including neuroendocrine tumor and neuroendocrine carcinoma. Herein, we reported the efficacy and safety of surufatinib in combination with toripalimab in a cohort of advanced NEC patients. Methods: The multicenter, open-label, single-arm phase II clinical trial enrolled advanced NEC patients refractory to first-line chemotherapy, and received surufatinib 250 mg once a day orally plus toripalimab 240 mg intravenously on day 1 of a 21-day cycle. The primary end point is objective response rate (ORR) per RECIST 1.1. Results: Twenty-one patients enrolled and received combination therapy. At data cut-off (December 31, 2020), the average treatment cycles were 5.1±3.69 for surufatinib and 5.0±3.68 for toripalimab. Among 20 tumor evaluable patients, 4 patients achieved confirmed PR and 10 patients achieved stable disease. The ORR and disease control rate (DCR) are 20 % (95%CI: 5.7%-43.7%) and 70% (95%CI: 45.7%-88.1%) respectively. The median PFS is 3.94 months (95%CI: 1.31- unknown). OS is not mature till data cut-off. Adverse events (AEs) reported as related to treatment (TRAE) occurred in 100% of patients, of which Grade≥3 TRAEs occurred in 33.3% of patients. The reported Grade≥3 TRAEs were hypertension in 2 (9.5%) patients, and upper abdominal pain, oral mucositis, neutrophil count decreased, leukocyte count decreased, dermatitis, anemia and backache in 1 (4.8%) patient each. Immune related Grade ≥3 AEs, Gamma-glutamyl transpeptidase increased and dermatitis, occurred in 2 (9.5%) patients, respectively. TRAE caused surufatinib or toripalimab interruption occurred in 6 (28.6%) and 4 (19%) patients respectively. There were neither serious AEs nor AEs inducing treatment discontinuations or deaths. Conclusions: As there is no standard second-line treatment, this combination of surufatinib and toripalimab might offer a new promising choice to treat NEC as second-line treatment due to good efficacy and manageable treatment related toxicities. Clinical trial information: NCT04169672.

Neoadjuvant combination of pazopanib or axitinib and programmed cell death protein-1-activated dendritic cell-cytokine-induced killer cells immunotherapy may facilitate surgery in patients with renal cell carcinoma

Background

Radical/cytoreductive nephrectomy or nephron-sparing surgery may be thought to be not safe or unfeasible in some renal cell carcinoma (RCC) patients in which tumor is locally advanced or highly complicated. Neoadjuvant therapy may reduce the volume of the tumor, thus facilitates surgery. The aim the study is to evaluate the efficacy and safety of neoadjuvant combination of pazopanib or axitinib and PD-1-activated dendritic cell-cytokine-induced killer (PD-1/DC-CIK) cell immunotherapy in those patients.

Methods

Data from 16 RCC patients who received neoadjuvant pazopanib (Group P, n=9) or axitinib (Group A, n=7) plus PD-1/DC-CIK cells immunotherapy were reviewed retrospectively. A total of 9 participants that were potential candidates for radical/cytoreductive nephrectomy (RN/CN) had locally advanced tumor and 5 participants with partial nephrectomy (PN) absolute indications had highly complicated tumors. The efficacy outcomes were based on volume changes of the primary tumor, lymph nodes, and tumor thrombus in 13 participants with complete computed tomography (CT) imaging. The treatment-related toxicities and surgical complications were also reported.

Results

With a median of 2.1 months treatment, the overall volume of the tumors decreased by a median of 42.30% [interquartile range (IQR): 19.37–66.78%]. Specifically, the median reduction of tumor volume was 88.77 and 15.50 cm³ in group P and group A, respectively (P=0.014). However, participants in Group P were more likely to experience grade 3 or 4 treatment-related adverse events (AEs) than those in Group A (44.4% vs. 0). Finally, all participants were candidates for appropriate surgery after neoadjuvant therapy (as assessed by the surgeon), and 10 participants accepted surgery, including 5 PN, 4 RN/CN, and 1 lymph node dissection. A solitary participant had Clavien grade IV acute renal failure required dialysis and another had grade II lymphatic leakage.

Conclusions

Neoadjuvant combination of pazopanib or axitinib and PD-1/DC-CIK cells immunotherapy was well-tolerated and could effectively reduce the volume of tumors in locally advanced or highly complicated RCC patients.

Severe delayed pulmonary toxicity following PD-L1-specific CAR-T cell therapy for non-small cell lung cancer

Objectives

This phase I study aimed to evaluate the antitumor effect and safety of programmed death‐ligand‐1 (PD‐L1)–targeting autologous chimeric antigen receptor T (CAR‐T) cells for patients with non‐small cell lung cancer (NSCLC).

Methods

Programmed death‐ligand‐1–specific CAR‐T cells were generated using lentiviral transduction. Four patients with NSCLC were recruited, but only one patient was finally involved. CAR‐T cells were infused on three different days (total dose during therapy, 1 × 10⁶ CAR‐T cells kg⁻¹ body weight). The date on which the patient received the first CAR‐T cell infusion was designated as Day 0.

Results

Circulating CAR‐T cells accounted for 3.30% of the patient’s peripheral blood T cells detected by FACS analysis during the first follow‐up (Day +29). The chest CT scan showed subtle tumor shrinkage (stable disease). On Day +43, the patient developed pyrexia without any known causes and dyspnoea that rapidly deteriorated to respiratory failure in 3 days. The chest X‐ray and CT scan showed bilateral extensive pulmonary infiltration in addition to the tumor silhouette on the left upper lung. The interleukin (IL)‐6 levels in serum dramatically increased (> 100‐fold). The patient was immediately transferred to the ICU where he received oxygen and intravenous infusions of tocilizumab and methylprednisolone. His symptoms rapidly improved and the pulmonary inflammation gradually resolved.

Conclusion

The clinical manifestations and test findings for this patient with NSCLC might represent unique clinical manifestations of solitary organ damage secondary to PD‐L1–specific CAR‐T cell therapy. The differential diagnosis, underlying mechanism and prevention and treatment strategies for such complications have also been discussed.

Phase I study results of APG-115, a MDM2-p53 antagonist in Chinese patients with advanced liposarcoma and other solid tumors

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Background: APG-115 is a potent, small-molecule MDM2 inhibitor and immune modulator with promising antitumor activities in various tumors, especially those wild-type TP53 with MDM2 amplification ( TP53wt+MDM2 amp). To better delineate safety, optimal dosage, and potential target population, we report updated results. Methods: Patients with advanced liposarcoma and other solid tumors received APG-115 (100-200 mg) orally every other day for 21 days of a 28-day cycle. The primary endpoints were safety and tolerability. Efficacy (assessed by RECIST v1.1), pharmacokinetics (PK) and pharmacodynamics (PD) have also been analyzed. Results: Enrollment of this Phase I study (CTR20170975) was completed. As of January 7, 2020, 21 patients (14 liposarcomas, 2 synovial sarcomas, 2 adenoid cystic carcinomas, 1 chondrosarcoma, 1 osteosarcoma, 1 rhabdomyosarcoma) were treated in 3 dose levels of APG-115: 100 mg (n = 11), 150 mg (n = 8) and 200 mg (n = 2). The median number of cycles of APG-115 was 2 (0; 6). Two DLTs were observed at 200 mg, thrombocytopenia and febrile neutropenia. The most common treatment-emergent adverse events (TEAEs) (≥20%) included leukopenia, thrombocytopenia, neutropenia, anemia, increased blood creatinine, hypercholesterolemia, hypertriglyceridemia, hypoalbuminemia, vomiting, and nausea. The incidence of TEAEs was much lower at 100 mg. Serious AEs occurred in 5 patients (23.8%) which were assessed as possibly drug related by investigators. In 20 efficacy-evaluable patients, there was 1 patient with a partial response, 12 patients with stable disease, and 7 patients with progressive disease, yielding a disease control rate (CR, PR, SD) of 61.9%. Among the 13 patients (9 liposarcomas) who benefited, 11 had TP53wt and 7 had TP53wt+MDM2 amp, including one liposarcoma patient (150 mg) who had a PR, she was kept-up over 10 months, even though the treatment was discontinued for over 5 months, indicating the host immune modulatory effects of APG-115. Another patient with liposarcoma (100 mg, TP53wt+MDM2 amp) had 28.5% tumor shrinkage at cycle 4 and remained on treatment. PK results showed an approximately dose-proportional increase in exposure on Day 1. PK-PD analyses showed the serum macrophage inhibitory cytokine-1 (MIC-1) increased with increased APG-115 exposure. Conclusions: The phase I data have demonstrated that APG-115 monotherapy was well tolerated, with minimal toxicity at 100mg (RP2D), and conferred encouraging anti-tumor activities in patients with liposarcomas. Clinical trial information: CTR20170975 .

A phase I study of a novel MDM2-P53 antagonist APG-115 in Chinese patients with advanced soft tissue sarcomas

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Background: APG-115 is a novel and orally active small-molecule MDM2 inhibitor. APG-115 alone or in combination with chemotherapeutic, targeted or IO agents have shown potent antitumor activities in multiple human xenograft tumor models and human cancer patient derived xenograft (PDX) models. Methods: The patients with advanced solid tumors were enrolled in this study in China (CTR20170975). The study objectives were to assess safety, pharmacokinetics (PK), pharmacodynamics (PD) and antitumor activity of APG-115. The patients received APG-115 (ranging 100–200 mg) orally QOD for first 21 days of a 28-day-cycle, until disease progression. Antitumor response assessment was performed every 8 weeks per RECIST v1.1. Archived tumor tissues were collected for analyses of MDM2 and TP53 before treatment. Results: As cut-off on Jan 4 2019, total 13 patients (9 soft tissue sarcomas (STSs), 2 adenoid cystic carcinomas (ACCs) and 2 osteosarcomas) were treated in 3 cohorts of APG-115 (100mg, 150mg, 200mg). The median number of prior systemic anticancer therapies was 2 (range 0-4). Two DLTs were observed in one patient at 200mg including thrombocytopenia and febrile neutropenia. The most common TEAEs (≥50% of pts) included: anemia, thrombocytopenia, vomiting, hypercholesterolaemia, and leukopenia. SAEs occurred in 7 patients (54%), four of which were treatment related. The most common Grade 3 or 4 TRAEs were anemia (38.5%), thrombocytopenia (38.5%), leukopenia (30.8%), and neutropenia (23.1%). One partial response was observed in a liposarcoma patient with MDM2-amplification and TP53-wild type at the 150mg cohort, 5 patients (3 STSs, 2 ACCs) had SD as the best overall response. PK analyses indicated an approximately dose proportional increase in Cmax and AUC0-t following a single or multiple oral administration across dose levels. Preliminary PD data showed that serum MIC-1 increase was exposure dependent within the dose range tested. Conclusions: Preliminary data suggested that APG-115 had promising anti-tumor activity in treatment of patients with MDM2-amplification and TP53-WT liposarcoma. Safety profile and PD effect were consistent with other MDM2 inhibitors. Dosing regimen optimization are ongoing. Clinical trial information: CTR20170975.

Abstract P1-09-06: Gene-set enrichment analysis (GSEA) of breast tissue from healthy women with less than six months history of breastfeeding shows enrichment in Hedgehog signaling, notch signaling and luminal progenitor gene signatures

Introduction: Multiple epidemiological studies have shown that prolonged breastfeeding is associated with a reduced risk of developing triple negative/basal-like breast cancer (TN/BLBC). We have modeled abrupt involution (AI) due to lack of breastfeeding and gradual involution (GI) of the mammary gland that occurs over time upon prolonged breastfeeding in wild-type FVB/N mice and discovered prominent histological and molecular changes in the AI glands over time. Our studies revealed for the first time a clear and persistent expansion of mammary luminal progenitor (LP) epithelial cells in AI glands (AACR abstract#2242, 2018). Here, we corroborate animal studies using normal human breast tissue obtained from a reduction mammoplasty tissue collection study (OSU-2011C0094).

Methods: Breast tissue obtained from parous premenopausal women with no history of breast cancer who breastfed for ≥6 months (GI, n=16) versus those who breastfed for <6 months (AI, n=16) (OSU-2011C0094) was used for gene expression analysis. RNA isolated from these normal mammary tissues was analyzed using Affymatrix Gene ChIP Human Transcriptome array 2.0; Gene Set Enrichment Analysis (GSEA) was used to analyze the microarray data. Molecular Signatures Database was used in GSEA querying C2 curated gene sets, Hallmark gene sets, and Lim-Mammary-Luminal-Progenitor gene sets. H&E sections of the breast tissue were used to assess lobular type by counting number of ductules per terminal ductal lobular unit (TDLU). False discovery rate (FDR) q-values and p-values were used for multiple comparison adjustment.

Results: GSEA revealed that breast tissue obtained from women in the AI cohort exhibited strong positive enrichment for Notch and Hedgehog Signaling (Hhg) pathways (FDR q-value= 0.20 and 0.12, respectively). In GI women, GSEA showed an overall trend towards enrichment in metabolic pathways and immune system functions. Moreover, there was non-significant trend towards positive enrichment of mouse LP gene signature in AI women only (FDR q-value= 0.30). Age and BMI were not statistically different between AI and GI cohorts. Analysis of TDLU, the primary anatomical source of most breast cancers, revealed that breast tissue from AI women had proportionally higher lobular type 1 only epithelium than GI women who exhibited more differentiated lobular epithelium (p-value= 0.049).

Conclusion: We report here for the first time that mammary glands from women who breastfed <6 months were enriched for stem-cell signaling pathways and LP gene signature. This reflects some similarity to BRCA1 mutation carriers, who demonstrate expanded luminal progenitor population. In addition, higher Type 1 TDLU's are seen in breast tissue from parous women who breastfed <6 months. Together, these data demonstrate features for TN/BLBC precursors enriched in patients who breastfed for <6 months. Understanding this mechanistic link will help in developing prevention strategies, particularly for African-American women who have lower prevalence of breastfeeding and higher incidence of TN/BLBC.

Citation Format: Basree MM, Shinde N, Palettas M, Weng D, Stover DG, Sizemore GM, Shields P, Majumder S, Ramaswamy B. Gene-set enrichment analysis (GSEA) of breast tissue from healthy women with less than six months history of breastfeeding shows enrichment in Hedgehog signaling, notch signaling and luminal progenitor gene signatures [abstract]. In: Proceedings of the 2018 San Antonio Breast Cancer Symposium; 2018 Dec 4-8; San Antonio, TX. Philadelphia (PA): AACR; Cancer Res 2019;79(4 Suppl):Abstract nr P1-09-06.

Platelet Deposition Induced by Severely Damaged Vessel Wall Is Inhibited by a Boroarginine Synthetic Peptide with Antithrombin Activity

Thrombin plays a key role in platelet activation and thrombosis. Specific inhibition of thrombin appears to be one of the best approaches to prevent thrombus formation. We have studied the effects of a synthetic a-aminoboronic acid derivative - [Ac, (D) Phe-Pro-Boro-Arg-Hydrocloric acid] - on platelet deposition on severely damaged arterial wall. Platelet deposition was evaluated under well characterized rheological conditions in an original perfusion chamber and detected by autologous mIn-labeled platelets. The study was performed “in vivo” in a porcine model of arterial thrombosis triggered by severely damaged vessel wall at blood flow conditions mimicking mild stenosis (1690 s−1) and patent (212 s−1) vessels. In addition, ex-vivo platelet aggregation activity was evaluated by whole blood impedance aggregometry using collagen, ADP and thrombin as agonists. The synthetic a-aminoboronic peptide was intravenously administered as a bolus followed by continuous infusion. Ex vivo thrombin-induced whole blood platelet aggregation was totally abolished, while ADP- and Collagen-induced whole blood platelet aggregation was not modified. The effects of the synthetic antithrombin on platelet deposition were evaluated in native blood (non-anticoagulated) conditions and in combination with heparin. Under both experimental conditions, the synthetic peptide significantly inhibited platelet deposition at local flow conditions of both high (1690 s−1) and low (212s−1) shear rates. Our results suggest that specific inhibition of locally generated thrombin might be a good strategy to prevent platelet dependent arterial thrombus formation independently of the local flow shear rate of the area at risk.

Genotoxic stress induces Sca-1-expressing metastatic mammary cancer cells

We describe a cell damage‐induced phenotype in mammary carcinoma cells involving acquisition of enhanced migratory and metastatic properties. Induction of this state by radiation required increased activity of the Ptgs2 gene product cyclooxygenase 2 (Cox2), secretion of its bioactive lipid product prostaglandin E2 (PGE2), and the activity of the PGE2 receptor EP4. Although largely transient, decaying to low levels in a few days to a week, this phenotype was cumulative with damage and levels of cell markers Sca‐1 and ALDH1 increased with treatment dose. The Sca‐1⁺, metastatic phenotype was inhibited by both Cox2 inhibitors and PGE2 receptor antagonists, suggesting novel approaches to radiosensitization.

Reduced expression of Rap1GAP as a prognostic biomarker for primary gastric cancer patients

BACKGROUND

Rap1GAP, a member of the family of GTPase-activating proteins, is reported to be involved in cancer development and progression.

OBJECTIVE

The study aimed to investigate the expression and prognostic value of Rap1GAP in gastric cancer patients.

METHODS

Real-time quantitative polymerase chain reaction and western blotting were performed to examine Rap1GAP expression in tumorous and matched adjacent non-tumorous gastric tissues. Immunohistochemical staining was used to analyze Rap1GAP expression in 456 gastric cancer tissues. The correlation between Rap1GAP expression level and clinicopathological features as well as gastric cancer prognosis was analyzed.

RESULTS

Rap1GAP expression was remarkably decreased in tumor tissues at mRNA (p= 0.012) and protein (p= 0.034) level. Clinicopathological analysis revealed that low Rap1GAP expression was significantly correlated with tumor size (p= 0.033), histological grade (p= 0.034), T classification (p= 0.012), N classification (p= 0.006) and clinical stage (p= 0.005). Kaplan-Meier survival analysis revealed the association between low Rap1GAP expression and poor survival in gastric cancer patients. Furthermore, multivariate Cox regression analysis showed that Rap1GAP expression was an independent prognostic factor (p= 0.02).

CONCLUSION

Rap1GAP may play a significant role in gastric cancer progression and act as a valuable prognostic marker for gastric cancer.

A favorable outcome of advanced dermatofibrosarcoma protuberans under treatment with sunitinib after imatinib failure

While traditional cytotoxic agents play a limited role in advanced dermatofibrosarcoma protuberans (DFSP), the treatment of sunitinib for patients with advanced DFSP after imatinib failure is not well defined. The objective of this case report was to analyze the relationship between molecular mechanisms and clinical outcomes of sunitinib treatment in patients with advanced DFSP after imatinib failure. In this case report, a 37-year-old man suffered from advanced DFSP progression after surgical operation, microwave ablation, and chemotherapy. The immunohistochemistry in this patient revealed abundant expression of platelet-derived growth factor receptor-beta on tumor cells, which is one of the drug targets of sunitinib. The nucleotide sequence analysis revealed COL1A1-PDGFB fusion transcripts in this patient. Thus, we treated the patient with sunitinib, a multi-targeted tyrosine kinase inhibitor, after imatinib failure. After treatment with sunitinib, the patient exhibited a partial response and 9 months’ progression-free survival without significant adverse drug effects. In our case, the patient with advanced DFSP experienced a favorable outcome in 9-months’ progression-free survival and a significant improvement of quality of life without serious side effects after sunitinib treatment. Therefore, sunitinib could serve as another treatment option for patients with advanced DFSP.

A Novel Heat Shock Protein 70-based Vaccine Prepared from DC-Tumor Fusion Cells

We have developed an enhanced molecular chaperone-based vaccine through rapid isolation of Hsp70 peptide complexes after the fusion of tumor and dendritic cells (Hsp70.PC-F). In this approach, the tumor antigens are introduced into the antigen processing machinery of dendritic cells through the cell fusion process and thus we can obtain antigenic tumor peptides or their intermediates that have been processed by dendritic cells. Our results show that Hsp70.PC-F has increased immunogenicity compared to preparations from tumor cells alone and therefore constitutes an improved formulation of chaperone protein-based tumor vaccine.

Rapid recurrence and bilateral lungs, multiple bone metastasis of malignant solitary fibrous tumor of the right occipital lobe: report of a case and review

BACKGROUND

Intracranial malignant solitary fibrous tumor (MSFT) is extremely rare. The authors report a case of MSFT of the right occipital lobe with a rapid recurrence and bilateral lung, multiple bone metastasis.

CASE PRESENTATION

The patient was a 25-year-old male presenting with headache, nausea and visual disturbances without obvious cause. Three times right-side occipital craniotomies were performed and two times postoperative conformal radiotherapy were administered within one year. 4 months after the third time of right-side occipital craniotomy, the patient felt right chest pain and neck pain. Positron emission tomography/computed tomography (PET/CT) showed tumor recurrence of the right occipital lobe and bilateral lung metastasis, multiple bone metastasis including: vertebrae, libs, the left iliac wing, sacrum, the right ischium and upper parts of both femurs. Ultrasound guided puncture biopsy of left-side back of the neck and CT guided puncture biopsy of the third lumbar vertebra were performed. General sample showed grayish white or grayish red with irregular shape. Histopathologically, the tumor was composed of areas of alternating hypercellularity and hypocellularity with spindle-shaped cells, which arranged as fascicular, storiform pattern or patternless pattern, with intervening irregular eosinophilic collagen bundles. Some areas showed hemangiopericytoma-like perivascular pattern and perivascular hyalinization. Tumor cells were pleomorphic with mitotic counts of more than 4 per 10 high power fields and showed coagulative necrosis. Immunohistochemically, tumor cells were diffusely positive for vimentin and CD99, focal positive for CD34, bcl-2 and Actin. Ki-67 labelling index was more than 40%. The final pathological diagnosis was MSFT of the right occipital lobe, metastatic MSFT of left-side back of the neck and the third lumbar vertebra.

CONCLUSION

The MSFT of the right occipital lobe with recurrence and bilateral lung, multiple bone metastasis is extremely rare. Although intracranial MSFT is extremely rare, it should be considered in the differential diagnosis. Definite diagnosis depended mainly on pathological morphology and immunohistochemistry. The prognosis of MSFT is poor due to recurrence and metastasis. Complete resection of intracranial MSFT is difficult, and carful follow-up is needed.

Immunotherapy of radioresistant mammary tumors with early metastasis using molecular chaperone vaccines combined with ionizing radiation

In the current study, exposure of mammary tumor cells derived from mice transgenic for the polyomavirus middle T oncogene to ionizing radiation resulted in the generation of a tumor cell population that preferentially expressed cancer stem cell markers. In addition, these cells were more resistant to subsequent radiation treatments and appeared to acquire an enhanced capacity for dissemination to the lungs of mice. Therefore, we tested an immunotherapy approach to the treatment of local and disseminated mammary tumor cells in a murine model using a recently developed molecular chaperone-based vaccine that specifically targets the radioresistant subpopulation of tumor cells. Heat shock protein 70-peptide complexes (Hsp70.PC-F) were extracted from fusions of dendritic cells and radiation-enriched tumor cells, and the resulting chaperone vaccines were used to treat mice with pre-existing lung metastases. Immunization of mice with the Hsp70.PC-F vaccine resulted in a T cell-mediated immune response, including a significant increase in CD4 and CD8 T cell proliferation and the induction of effector T cells capable of targeting radioresistant tumor cells. Importantly, the growth of primary tumors was inhibited, and the number of tumor cells metastasizing to lung was reduced significantly by combining chaperone vaccine with radiotherapy. These results indicate that Hsp70.PC-F vaccine can induce specific immunity to radioresistant populations of mammary tumor cells and, thus, can complement radiotherapy, leading to synergistic killing.

Quantitative proteome analysis of overexpressed Cripto-1 tumor cell reveals 14-3-3γ as a novel biomarker in nasopharyngeal carcinoma

We previously found that Cripto-1 is involved in the tumorigenesis of nasopharyngeal carcinoma (NPC). Here, to identify new NPC related proteins and to investigate the clinicopathological correlations of it in NPC, Cripto-1 over-expressed cell (CNE1/CR1(+)) was established. Two-dimensional difference in gel electrophoresis (2D-DIGE) analysis and matrix-assisted laser desorption time-of-flight mass spectrometry (MALDI-TOF MS) were used to identify 23 differential proteins in CNE1/CR1(+) and parental cells. Among them, 14-3-3γ showed the potential to be a NPC related protein. 14-3-3γ expression was found in 58.3% (60/103) tumor tissues as detected by IHC, and 69.6% (16/23) NPC fresh tumors expressed higher 14-3-3γ than paired non-cancerous tissues as detected by Western blot. Moreover, 14-3-3γ expression was positively correlated with N classification (p=0.031), distant metastasis (M classification, p=0.018) and clinical stage (p=0.046) of NPC patients. As determined by the Kaplan-Meier method, 14-3-3γ expression in NPC was significantly associated with overall survival (p=0.015). Multivariate analysis also showed that the expression of 14-3-3γ protein was an independent prognostic factor for outcome of NPC. In this study, we identified upregulated 14-3-3γ by 2D-DIGE in CNE1/CR-1(+). We also demonstrated that 14-3-3γ might be a potential biomarker for the prognosis of patients with NPC.

BIOLOGICAL SIGNIFICANCE

We believe that three aspects of this manuscript will make it interesting to general readers of Journal of Proteomics. Firstly, based on our previous report, we further validated that Cripto-1 can promote the proliferation and invasion of nasopharyngeal carcinoma (NPC). In this context, we used 2D-DIGE to identify new NPC related proteins. As a result, 14-3-3γ showed the potential to be a candidate. Secondly, we reported for the first time that the expression level of 14-3-3γ was significantly increased in human NPC patient tissues, and 14-3-3γ overexpression correlated statistically with N classification, distant metastasis, and clinical stage. Our results highlight the clinical significance of 14-3-3γ in NPC. Finally, we found that high 14-3-3γ expression is associated with poor survival in NPC patients. Thus, this study has identified that the 14-3-3γ involves in the carcinogenesis of NPC. Our findings may also provide new insights into understanding the molecular mechanism involved in NPC carcinogenesis and progression, and may lead to the development of new approaches for effective diagnosis and therapy.

Metastasis is an early event in mouse mammary carcinomas and is associated with cells bearing stem cell markers

Introduction

It is still uncertain whether metastasis is predominantly an early or late event in tumor progression. The detection of early metastases and cells responsible for the dissemination may therefore have significant clinical implications.

Methods

Lung dissemination and/or metastasis were investigated in mice carrying the polyomavirus middle-T oncogene (PyMT) during different stages of mammary tumorigenesis using the colony forming assay. Immunocytochemical or immunohistochemical staining was used to identify subpopulations of cells responsible for lung dissemination and metastasis. Histological examination was used to show primary and metastatic tumors. The tumor-initiating and metastatic capacity of cells expressing stem cell markers was assessed in syngeneic wild-type (WT) mice whose mammary fat pads were injected with these cells.

Results

Metastatic mammary epithelial cells were detected in the lungs of mice carrying the PyMT oncogene (MMT mice). These cells were observed early in breast tumorigenesis when the mammary tree appeared by histological inspection to be normal (or at a premalignant stage), suggesting the possession of disseminating and metastatic capacity even before full malignant transformation. Some of the disseminated cells and lung metastases displayed surface stem cell markers. These findings suggest that stem cells from apparently precancerous primary lesions could be a source of metastasis. Indeed, injection of lung tissue cells from MMT mice into syngeneic WT mice resulted in the formation of mammary tumors. These tumors resembled their parent mammary tumors in the MMT donors as well as grafted tumors derived from mammary tumor cells. Furthermore, when we injected lung tissue cells from GFP MMT mice into the fat pads of recipient WT mice, disseminated or metastatic GFP-expressing cells were detected in the lungs, lymph nodes and blood of the recipient WT mice. We finally identified a subpopulation of mammary epithelial/tumor cells expressing CD44 and Sca1 that was largely responsible for dissemination and metastasis in MMT mice.

Conclusions

The tumorigenic and metastatic potential of a subpopulation of mammary epithelial/tumor cells in MMT mice is endowed relatively early in mammary neoplasms and suggests a potential role for cancer stem cell sub-populations in metastasis.

Induction of cytotoxic T lymphocytes against ovarian cancer-initiating cells

The majority of patients with stage III/IV ovarian carcinoma that respond initially to standard therapies ultimately undergo relapse due to the survival of small populations of cells with tumor-initiating potential. These ovarian cancer (OVCA)-initiating cells (OCIC) are sometimes called cancer stem cells (CSC) because they express stem cell markers, and can survive conventional therapies such as chemotherapy, which usually target rapidly replicating tumor cells, and give rise to recurrent tumors that are more chemo-resistant and more aggressive. Thus, it would be desirable to develop a therapy that could selectively target OCIC and be used to complement the conventional therapies. In this study, we isolated a subset of OVCA cells with a CD44(+) phenotype in samples from patients with OVCA that possess CSC properties including the formation of spheroids in culture, self-renewal and the ability to be engrafted in immune-compromised mice. We next explored the use of immunotherapy using fusions of dendritic cells and OCIC to specifically target the OCIC subpopulations. Fusion cells (FCs) prepared in this way activated T cells to express elevated levels of IFN-γ with enhanced killing of CD44(+) OVCA cells. We envision a combined approach where conventional therapies such as chemotherapy kill the bulk of tumor cells, whereas OCIC-reactive cytotoxic T lymphocytes target the resistant OCIC fraction. A combined therapy such as this may represent a promising approach for the treatment of OVCA.

Stratification of Fullerenes

Dodecylated C60 {(Do)nC60(H)n} and butylated C60 {(Bu)nC60(H)n} were synthesized. Spectroscopic and thermal methods, mass spectrometry, XPD, have been employed to characterize the products. X-ray Powder Diffraction (XPD) results reveal that the facecentered- cubic (fcc) structure of C60 expands to a primitive hexagonal structure upon butylation and to a layered structure upon dodecylation. Butylated C60 diffraction pattern has been indexed as a primitive hexagonal structure with ao = 11.5 angstroms and axial ratio = 1.169. The dodecylated C60 also shows sidechain melting behavior with a transition temperature of around 25°C. The paraffinic crystals are produced by the interdigitation of the sidechains. Butylated C60 does not show any sidechain melting.

Preparation of a heat-shock protein 70-based vaccine from DC-tumor fusion cells

We have developed an enhanced molecular chaperone-based vaccine through rapid isolation of heat-shock protein 70 peptide complexes (Hsp70.PC) after the fusion of tumor and dendritic cells (DCs) (Hsp70.PC-F). In this approach, the tumor antigens are introduced into the antigen-processing machinery of dendritic cells through the cell fusion process and, thus, we can obtain antigenic tumor peptides or their intermediates that have been processed by dendritic cells. Our results show that Hsp70.PC-F has increased immunogenicity compared to preparations from tumor cells alone and, therefore, constitutes an improved formulation of chaperone protein-based tumor vaccine.

Extensive analysis of D7S486 in primary gastric cancer supports TESTIN as a candidate tumor suppressor gene

BACKGROUND

High frequency of loss of heterozygosity (LOH) was found at D7S486 in primary gastric cancer (GC). And we found a high frequency of LOH region on 7q31 in primary GC from China, and identified D7S486 to be the most frequent LOH locus. This study was aimed to determine what genes were affected by the LOH and served as tumor suppressor genes (TSGs) in this region. Here, a high-throughput single nucleotide polymorphisms (SNPs) microarray fabricated in-house was used to analyze the LOH status around D7S486 on 7q31 in 75 patients with primary GC. Western blot, immunohistochemistry, and RT-PCR were used to assess the protein and mRNA expression of TESTIN (TES) in 50 and 140 primary GC samples, respectively. MTS assay was used to investigate the effect of TES overexpression on the proliferation of GC cell lines. Mutation and methylation analysis were performed to explore possible mechanisms of TES inactivation in GC.

RESULTS

LOH analysis discovered five candidate genes (ST7, FOXP2, MDFIC, TES and CAV1) whose frequencies of LOH were higher than 30%. However, only TES showed the potential to be a TSG associated with GC. Among 140 pairs of GC samples, decreased TES mRNA level was found in 96 (68.6%) tumor tissues when compared with matched non-tumor tissues (p < 0.001). Also, reduced TES protein level was detected in 36 (72.0%) of all 50 tumor tissues by Western blot (p = 0.001). In addition, immunohistochemical staining result was in agreement with that of RT-PCR and Western blot. Down regulation of TES was shown to be correlated with tumor differentiation (p = 0.035) and prognosis (p = 0.035, log-rank test). Its overexpression inhibited the growth of three GC cell lines. Hypermethylation of TES promoter was a frequent event in primary GC and GC cell lines. However, no specific gene mutation was observed in the coding region of the TES gene.

CONCLUSIONS

Collectively, all results support the role of TES as a TSG in gastric carcinogenesis and that TES is inactivated primarily by LOH and CpG island methylation.

Analysis of loss of heterozygosity on chromosome 4q in hepatocellular carcinoma using high-throughput SNP array

To identify tumour suppressor genes (TSGs) associated with hepatocellular carcinoma (HCC) on chromosome 4q using a high-throughput single nucleotide polymorphism (SNP) array, we first scanned for loss of heterozygosity (LOH) of 40 SNPs on chromosome 4q and discovered 2 hot regions: 4q24-26 and 4q34.3-35. We then further scanned for LOH of 338 SNPs in genes around 4q34.3-35 and discovered 3 genes with the most frequent LOH: nei endonuclease VIII-like 3 (NEIL3), interferon regulatory factor 2 (IRF2) and inhibitor of growth family member 2 (ING2). A review of the literature indicates only ING2 might be a TSG associated with HCC.

A heat shock protein 70-based vaccine with enhanced immunogenicity for clinical use

In previous studies, we have shown that heat shock protein 70-peptide complexes (HSP70.PCs) derived from the fusion of dendritic cells (DCs) to tumor cells (HSP70.PC-F) possess superior properties compared with HSP70.PCs from tumor cells. HSP70.PC-F are more effective in stimulation of DC maturation and induction of CTL that are able to provide protection of mice against challenge with tumor cells. To develop an improved formulation of HSP70.PC-based tumor vaccine for patient use, we extracted HSP70.PC-F from DCs fused to patient-derived ovarian cancer cells or established human breast cancer cells and examined their properties as tumor vaccines. HSP70.PC-F induced T cells that expressed higher levels of IFN-gamma and exhibited increased levels of killing of tumor cells, compared with those induced by HSP70.PC derived from tumor cells. Enhanced immunogenicity of HSP70.PC-F was associated with improved composition of the vaccine, including increased content of tumor Ags and their processed intermediates, and the detection of other heat shock proteins (HSPs) such as HSP90 and HSP110. The present study has therefore provided an alternative approach to preparation of HSP-based vaccines using DC/tumor fusion technology and gentle and rapid isolation of HSP peptide complexes.

Patient-derived renal cell carcinoma cells fused with allogeneic dendritic cells elicit anti-tumor activity: in vitro results and clinical responses

Renal cell carcinoma (RCC) has been shown to be susceptible to immunotherapeutic treatment strategies. In the present study, patient-derived tumor cells were fused with allogeneic dendritic cells (DC) to elicit anti-tumor activity against RCC. DC from HLA-A2+ healthy donors were fused with primary RCC cells from ten patients. Phenotype of fusion cells were characterized by flow cytometer and confocal microscopy. In vitro, T cell proliferation, IFN-gamma secretion and cytotoxic T lymphocytes (CTL) activity elicited by allogeneic DC/RCC fusion cells were assessed. Clinically, ten patients were vaccinated with allogeneic DC/RCC fusion vaccine. The adverse effects and toxicity were observed. The clinical response was evaluated by CT scans. After fusion, the created hybrids expressed both tumor associated antigen and DC-derived molecules and could stimulate the proliferation and IFN-gamma secretion of T cells as well as elicit strong CTL activity against RCC cells in vitro. In vivo, no serious adverse effects, toxicity, or signs of autoimmune disease were observed after vaccination therapy. Percentage of T lymphocyte subsets in peripheral blood of patients was increased significantly. One of ten patients exhibited a partial response with regression of lung metastases. Six patients showed stable disease with stabilization of previously progressive disease (follow up 1.5 years). The PR and SD responses, exhibited by 7/10 patients who received the allogeneic DC/RCC fusion vaccine treatment, suggest that this approach is safe and can elicit immunological responses in a significant portion of patients with RCC.

Cripto-1 overexpression is involved in the tumorigenesis of nasopharyngeal carcinoma

Background

Human Cripto-1, a member of the EGF-CFC family, is indispensable for early embryonic development. Cripto-1 plays an important oncogenic role during tumorigenesis and is overexpressed in a wide range of epithelial carcinomas, yet little is known about Cripto-1 in nasopharyngeal carcinoma (NPC). The aim of this study was to analyze the roles of Cripto-1 in the progression and clinical characteristics in NPC clinical samples and cell lines.

Methods

The expression of Cripto-1 at mRNA level was detected by the reverse transcription-polymerase chain reaction (RT-PCR) and real time RT-PCR, and western blot was used to examine the protein expression. Cripto-1 expression and its clinical characteristics were investigated by performing immunohistochemical analysis on a total of 37 NPC clinical tissue samples. Lentiviral vectors were constructed to get an efficient expression of anti-Cripto-1 siRNA in CNE-2 and C666-1 cells, with invalid RNAi sequence as control. After the inhibition of the endogenous Cripto-1, the growth, cell cycle and invasion of cells were detected by MTT, FACS and Boyden chamber assay respectively. Moreover, in vivo, the proliferation of the tumor cells was evaluated in xenotransplant nude mice model with whole-body visualizing instrument.

Results

The results of real-time RT-PCR and western blot showed that the expression level of Cripto-1 was markedly higher in NPC cell lines than that in the immortalized nasopharyngeal epithelial cell at both mRNA and protein levels. RT-PCR of 17 NPC tissues showed a high expression rate in 76.5% (13/17) cases. In an immunohistochemical study, Cripto-1 was found to express in 54.1% (20/37) cases of NPC. In addition, Cripto-1 overexpression was significantly associated with N classification (p = 0.034), distant metastasis (p = 0.036), and clinical stage (p = 0.007). Inhibition of endogenous Cripto-1 by lentivirus-mediated RNAi silencing technique suppressed NPC cell growth and invasion in vitro. In vivo, the average weight (p = 0.026) and volume (p = 0.044) of tumor in CNE-2/GFP⁺/Cripto-1^- xenotransplant mice group were significantly lower than those in the control group. The Ki67 index was obviously lower in Cripto-1 RNAi treated tumors (p < 0.01).

Conclusion

Data of this study suggest that Cripto-1 overexpression is connected with the tumorigenesis and progression of NPC, lentivector-mediated RNAi might be feasible for the inhibition of the growth and invasion of NPC.

Reduced expression of lamin A/C correlates with poor histological differentiation and prognosis in primary gastric carcinoma

Background

Lamin A/C is very important in DNA replication, RNA dependent transcription and nuclear stabilization. Reduced or absent lamin A/C expression has been found to be a common feature of a variety of different cancers. To investigate the role of lamin A/C in gastric carcinoma (GC) pathogenesis, we analyzed the correlations between the lamin A/C expression level and clinicopathological factors and studied its prognostic role in primary GC.

Methods

The expression of lamin A/C at mRNA level was detected by the reverse transcription-polymerase chain reaction (RT-PCR) and real time RT-PCR, and western blot was used to examine the protein expression. Lamin A/C expression and its prognostic significance were investigated by performing immunohistochemical analysis on a total of 126 GC clinical tissue samples.

Results

Both lamin A/C mRNA and protein expression were downregulated in the majority of tumours compared with corresponding normal gastric tissues (p = 0.011 and p = 0.036, respectively). Real time RT-PCR further validated that downregulation of lamin A/C is associated with poor histological differentiation (r = 0.438, p = 0.025). The immunohistochemical staining showed an evident decrease of lamin A/C expression in 55.6% (70/126) GC cases. Importantly, the negative lamin A/C expression correlated strongly with histological classification (r = 0.361, p = 0.034). Survival analysis revealed that patients with lamin A/C downregulation have a poorer prognosis (p = 0.034). In addition, lamin A/C expression was found to be an independent prognostic factor by multivariate analysis.

Conclusion

Data of this study suggest that lamin A/C is involved in the pathogenesis of GC, and it may serve as a valuable biomarker for assessing the prognosis for primary GC.

BRCA mutation status and risk of secondary malignancy following chemotherapy for breast cancer

11017

Background: Since the BRCA gene is responsible for excisional DNA repair, we hypothesized that breast cancer patients with BRCA mutation would be more susceptible to the induction of second malignancies following chemotherapy treatment than breast cancer patients who tested negative for BRCA mutations. Methods: Breast cancer patients tested for BRCA1 and BRCA2 mutations at the Cleveland Clinic were identified and evaluated for history of neoadjuvant or adjuvant chemotherapy and for the occurrence of subsequent non-breast primary invasive cancer. Patients with inadequate follow-up and those with inoperable disease at diagnosis were excluded from the analysis. Fisher’s exact test was used to compare different cohorts. The IRB at Cleveland Clinic approved the study. Results: Of 115 identified breast cancer patients tested for BRCA mutations, 77 met the inclusion criteria. Twenty-seven of these patients carried BRCA1 or BRCA2 mutations and 50 tested negative for these mutations. Twelve patients (44%) in the BRCA positive group and 8 patients (16%) in the BRCA negative group underwent prophylactic oophorectomy. Median follow-up for the two groups was 53.5 months (75 months in the BRCA positive group and 48.5 months in the BRCA negative group). Median age at diagnosis was 42 years (40.5 years in the BRCA positive group and 44.5 in the BRCA negative group). In the BRCA positive group 3 of 25 patients (12%) treated with chemotherapy developed second malignancies (ovarian cancer, transitional cell cancer in urinary tract and renal cell carcinoma) compared with none of the 2 patients who did not get chemotherapy (p= 1.0). In the BRCA negative group, 2/34 patients (6%), treated with chemotherapy developed second cancers compared with 2/16 patients (12%), who were not treated with chemotherapy (p=0.58). Cancers in the BRCA negative group included two bladder carcinomas in the chemotherapy treated patients and in the non-chemotherapy group, non-small cell lung cancer, uterine, ovarian, endometrial and peritoneal cancers. Conclusions: At more than 4-years of follow up, chemotherapy in operable breast cancer patients was not associated with an increase in the risk of secondary malignancy or with a differential effect on this endpoint by BRCA mutation status in this retrospective study.

No significant financial relationships to disclose.

Therapeutic radiation for breast cancer in BRCA mutation carriers and contralateral breast cancer (CBC) risk

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Background: BRCA mutation carriers diagnosed with breast cancer are at high risk for contralateral second primary breast cancers. Mutations in BRCA1 and BRCA2 lead to defects in DNA repair. Radiation treatment for breast cancer is felt to increase risk of CBC, but the interaction between BRCA status and local radiation therapy with respect to their effects on CBC is unclear. Methods: Through an IRB approved database registry at the Cleveland Clinic, breast cancer patients tested for BRCA1 and BRCA2 mutations were identified and evaluated for CBC events and radiation treatment history. Patients with inadequate clinical follow-up, those with bilateral synchronous breast cancer and those undergoing bilateral mastectomy within one year of the original breast cancer diagnosis were excluded from the analysis. Chi-square test was used to compare CBC rates with or without prior radiation separately in patients testing positive and those testing negative for BRCA mutations. Results: Of 115 identified breast cancer patients tested for BRCA mutations, 57 met the inclusion criteria. Twenty-one carried BRCA1 or BRCA2 mutations and 36 tested negative for these mutations. Median follow-up for the two groups was 69.5 months (92 months in BRCA positive group and 51.5 months in BRCA negative group). Median age at diagnosis was 45 years (41 years in BRCA positive group and 48.5 in BRCA negative group). Among the 21 carriers, 9 patients (43%) developed CBC while only 3 of 36 patients (8%) testing negative for BRCA mutations developed CBC. Thirteen of 21 mutation carriers (62%) had received radiation treatment for the original cancer: CBC occurred in 3 of 13 (23%) radiated patients and 6 of 8 (75%) patients who had not received radiation (p= 0.02). Among 36 patients with negative BRCA testing, 30 (83%) had received radiation: CBC occurred in 3 of 30 (10%) mutation negative patients who had received prior radiation and in 0 of the 6 patients who had not received radiation (p = 0.42). Conclusions: CBC incidence was higher among BRCA mutation carriers than a control group suspected of having hereditary breast cancer but testing negative for these mutations. The use of radiation in the presence of a BRCA mutation, however, does not appear to further increase the risk for CBC.

No significant financial relationships to disclose.

Organ distribution of severe acute respiratory syndrome (SARS) associated coronavirus (SARS-CoV) in SARS patients: implications for pathogenesis and virus transmission pathways

We previously identified the major pathological changes in the respiratory and immune systems of patients who died of severe acute respiratory syndrome (SARS) but gained little information on the organ distribution of SARS‐associated coronavirus (SARS‐CoV). In the present study, we used a murine monoclonal antibody specific for SARS‐CoV nucleoprotein, and probes specific for a SARS‐CoV RNA polymerase gene fragment, for immunohistochemistry and in situ hybridization, respectively, to detect SARS‐CoV systematically in tissues from patients who died of SARS. SARS‐CoV was found in lung, trachea/bronchus, stomach, small intestine, distal convoluted renal tubule, sweat gland, parathyroid, pituitary, pancreas, adrenal gland, liver and cerebrum, but was not detected in oesophagus, spleen, lymph node, bone marrow, heart, aorta, cerebellum, thyroid, testis, ovary, uterus or muscle. These results suggest that, in addition to the respiratory system, the gastrointestinal tract and other organs with detectable SARS‐CoV may also be targets of SARS‐CoV infection. The pathological changes in these organs may be caused directly by the cytopathic effect mediated by local replication of the SARS‐CoV; or indirectly as a result of systemic responses to respiratory failure or the harmful immune response induced by viral infection. In addition to viral spread through a respiratory route, SARS‐CoV in the intestinal tract, kidney and sweat glands may be excreted via faeces, urine and sweat, thereby leading to virus transmission. This study provides important information for understanding the pathogenesis of SARS‐CoV infection and sheds light on possible virus transmission pathways. This data will be useful for designing new strategies for prevention and treatment of SARS. Copyright © 2004 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.