Mutant p53 drives an immune cold tumor immune microenvironment in oral squamous cell carcinoma

The critical role of the tumor immune microenvironment (TIME) in determining response to immune checkpoint inhibitor (ICI) therapy underscores the importance of understanding cancer cell-intrinsic mechanisms driving immune-excluded ("cold") TIMEs. One such cold tumor is oral cavity squamous cell carcinoma (OSCC), a tobacco-associated cancer with mutations in the TP53 gene which responds poorly to ICI therapy. Because altered TP53 function promotes tumor progression and plays a potential role in TIME modulation, here we developed a syngeneic OSCC models with defined Trp53 (p53) mutations and characterized their TIMEs and degree of ICI responsiveness. We observed that a carcinogen-induced p53 mutation promoted a cold TIME enriched with immunosuppressive M2 macrophages highly resistant to ICI therapy. p53-mutated cold tumors failed to respond to combination ICI treatment; however, the combination of a programmed cell death protein 1 (PD-1) inhibitor and stimulator of interferon genes (STING) agonist restored responsiveness. These syngeneic OSCC models can be used to gain insights into tumor cell-intrinsic drivers of immune resistance and to develop effective immunotherapeutic approaches for OSCC and other ICI-resistant solid tumors.

Body mass index increases the recurrence risk of breast cancer: a dose-response meta-analysis from 21 prospective cohort studies

OBJECTIVE

The purpose of this study was to investigate the effect of body mass index (BMI) on the recurrence risk of breast cancer.

STUDY DESIGN

Dose-response meta-analysis.

METHODS

Cohort studies that included BMI and the recurrence of breast cancer were selected through various databases including PubMed, Web of Science, the China National Knowledge Infrastructure (CNKI), Chinese Scientific Journals (VIP), and Wanfang Data Knowledge Service Platform (WanFang) until November 30, 2021. The Newcastle-Ottawa Scale (NOS) was used to evaluate the quality of literature. A two-stage random-effects meta-analysis was performed to assess the dose-response relationship between BMI and breast cancer recurrence risk. Heterogeneity between studies is assessed using I².

RESULTS

The relative risk (RR) of BMI <25 kg/m² vs BMI ≥25 kg/m², BMI <30 kg/m² vs BMI ≥30 kg/m² were 1.09 (95% CI: 1.00-1.19) and 1.15 (95% CI: 1.04-1.27), suggesting that BMI had a significant effect on the recurrence risk of breast cancer, and there might be a dose-response relationship between them. A total of 21 studies were included in dose-response meta-analysis, which showed that there was a positive linear correlation between BMI and the risk of recurrence (RR = 1.02, 95% CI: 1.01-1.03). For every 1 kg/m² increment of BMI, the risk of recurrence increased by approximately 2%. In subgroup analyses, positive linear dose-response relationships between BMI and recurrence risk were observed among Asian and study period >10 years groups. For every 1 kg/m² increment of BMI, the risk of recurrence increased by 3.41% and 1.87%, respectively.

CONCLUSIONS

The recurrence risk of breast cancer increases with BMI, which is most obvious among Asian women.

[Management of the internal carotid artery during lateral skull base surgery: a series of 41 cases]

Objective: To introduce our experience on dealing with the internal carotid artery (ICA) during the resection of lateral skull base tumors, and to explore the reference values for using radiological findings to make a rational surgical plan. Methods: A retrospective study of patients who underwent resection of lateral skull base tumors involving ICA at Peking Union Medical College Hospital from May 2015 to May 2021 was conducted. The demographic information, preoperative examinations, diagnosis, surgical details and follow-ups were collected. A total of 41 patients were enrolled [24 (58.5%] females, 17 (41.5%) males], with an average age of 47.9 years. According to the preoperative imaging findings, the relationships between the tumors and ICA were divided into four types: adjacency, compression, invasion and ICA aneurysm. Results: The ICA was preserved in 32 (78.0%, 32/41) cases and was reconstructed in nine (22.0%, 9/41) cases. All the 27 (65.9%, 27/41) tumors adjacent to ICA were successfully separated from the artery. Among the 11 tumors compressing the ICA, six were resected with the involved ICA segment and vascular reconstruction was conducted. One (2.4%, 1/41) tumor invading ICA and two (4.9%, 2/41) ICA aneurysms required revascularization. The mean follow-up time was (26.1±2.9) months. There was no recurrence, except one case of adenoid cystic carcinoma which had brain metastases one year after surgery. Conclusions: According to the preoperative imaging, lateral skull base tumors adjacent to ICA can be detached from the vascular surface. Separation should be attempted first for tumors compressing ICA, and revascularization should be followed if separation failed. Vascular reconstruction is usually needed in the removal of tumors invading ICA and ICA aneurysms. Preoperative radiology can provide good references for planning a surgery for lateral skull base tumors.

[Berberine inhibits erastin-induced ferroptosis of mouse hippocampal neuronal cells possibly by activating the Nrf2-HO-1/GPX4 pathway]

OBJECTIVE

To explore the mechanism by which berberine inhibits ferroptosis of mouse hippocampal neuronal cells (HT22).

METHODS

Cultured HT22 cells were pretreated with 30 or 60 μmol/L berberine for 2 h before exposure to 0.5 μmol/L erastin for 8 h, and the cell proliferation, intracellular ferric iron level, changes in intracellular reactive oxygen species (ROS) and cell apoptosis were detected using CCK-8, Fe²⁺ fluorescent probe, fluorescent dye (DAPI) and fluorescent probe (H2DCFH-DA). RT-qPCR and Western blotting were used to detect the mRNA and protein expressions of Nrf2, HO-1 and GPX4 in the cells. We further tested the effects of treatments with 2 μmol/L ML385 (a Nrf2 inhibitor), 60 μmol/L berberine and erastin in the cells to explore the protective mechanism of berberine against erastin-induced ferroptosis in the neuronal cells.

RESULTS

Treatment with 0.5 μmol/L erastin significantly lowered the viability of HT22 cells (P < 0.05) and increased the production of ROS, cell apoptosis rate and ferric iron level (P < 0.05). Pretreatment with 30 and 60 μmol/L berberine both significantly increased the vitality of erastin-exposed cells (P < 0.05) and lowered the levels of intracellular ROS and ferric iron content (P < 0.05). RT-qPCR and Western blotting showed that berberine obviously promoted the expressions of Nrf2, HO-1 and GPX4 in the cells (P < 0.05), and treatment with ML385 significantly inhibited the Nrf2-HO-1/GPX4 pathway, increased intracellular ROS and ferric iron contents and mitigated the protective effect of berberine against erastin-induced ferroptosis (P < 0.05).

CONCLUSION

Berberine can inhibit erastin-induced ferroptosis in HT22 cells possibly by activating the Nrf2-HO-1/ GPX4 pathway.

The Safety and Efficacy of Flow Diversion versus Conventional Endovascular Treatment for Intracranial Aneurysms: A Meta-analysis of Real-world Cohort Studies from the Past 10 Years

BACKGROUND

Although the flow diverter has advantages in the treatment of intracranial aneurysms, pooled studies that directly compare it with conventional endovascular treatments are rare.

PURPOSE

Our aim was to compare the safety and efficacy of flow-diverter and conventional endovascular treatments in intracranial aneurysms.

DATA SOURCES

We performed a comprehensive search of the literature using PubMed, EMBASE, and the Cochrane Database.

STUDY SELECTION

We included only studies that directly compared the angiographic and clinical outcomes of flow-diverter and conventional endovascular treatments.

DATA ANALYSIS

Random effects or fixed effects meta-analysis was used to pool the cumulative rate of short- and long-term angiographic and clinical outcomes.

DATA SYNTHESIS

Eighteen studies with 1001 patients with flow diverters and 1133 patients with conventional endovascular treatments were included; 1015 and 1201 aneurysm procedures were performed, respectively. The flow-diverter group had aneurysms of a larger size (standard mean difference, 0.22; 95% CI, 0.03-0.41; P = .026). There was a higher risk of complications in the flow-diverter group compared with the conventional endovascular group (OR, 1.4; 95% CI, 1.01-1.96; P = .045) during procedures. The follow-up angiographic results of flow-diverter treatment indicated a higher rate of complete occlusion (OR, 2.55; 95% CI, 1.70-3.83; P < .001) and lower rates of recurrence (OR, 0.24; 95% CI, 0.12-0.46; P < .001) and retreatment (OR, 0.31; 95% CI, 0.21-0.47; P < .001).

LIMITATIONS

Limitations include a retrospective, observational design in some studies, high heterogeneity, and selection bias.

CONCLUSIONS

Compared with the conventional endovascular treatments, the placement of a flow diverter may lead to more procedure-related complications, but there is no difference in safety, and it is more effective in the long term.

Abstract 2016: Preclinical evaluation of uPARAP (MRC2) antibody-drug conjugates (ADCE-003,010,011) in osteosarcoma pdx models

Introduction: Antibody-drug Conjugates (ADCs) targeting differentially expressed tumor cell-surface antigens show robust clinical activity in several solid tumor cancers, but none is yet available for osteosarcoma. Due to the high unmet medical need in this indication, there is an urgent requirement to identify respective osteosarcoma cell-surface antigens and evaluate the antitumor activity of an ADC that can deliver tailored cytotoxic payloads to osteosarcoma tumors expressing these targets.

Methods: We used an integrated proteomic and transcriptomic surfaceome profiling approach to identify cell-surface proteins that are highly expressed in osteosarcoma but minimally expressed on normal tissues. uPARAP (MRC2) was found to be enriched in osteosarcoma at both protein and mRNA levels. The cell-surface expression of uPARAP (MRC2) was further validated by IHC and flow cytometry with osteosarcoma cell lines, PDX models, and patient tumor tissue microarray. As a proof of concept, three MRC2 targeted ADCs with different Microtubulin- and alkylating agent types of payloads were tested in 8 osteosarcoma PDX models. uPARAP (MRC2) ADC, control ADC, or vehicle control was administered IV to mice harboring flank tumors at a dose of 3mg/kg, weekly X 3 (ADCE-003), 2mg/kg on Day 1 (ADCE-010), and 10mg/kg weekly X 2 (ADCE-011). EFS for treatment (T) and control (C) groups, minimum relative tumor volume (minRTV), and objective response measures were analyzed.

Results: Western blotting confirmed the expression of uPARAP (MRC2) in 8 osteosarcoma cell lines and 8 PDX models. Flow cytometry further validated cell-surface localization and expression levels of uPARAP (MRC2) in 7 osteosarcoma cell lines. We then performed immunohistochemistry (IHC) staining using an osteosarcoma tissue microarray from 37 patients and 19 PDX models. uPARAP (MRC2) was expressed in 97% of the patient samples and 95% of the PDXs. 51% of the patient samples and 39% of the PDXs had an overall H-score of 100 or higher. Mice tolerated ADCs well with minimal toxicity. All 3 ADCs significantly prolonged EFS in 6/8 osteosarcoma models. Complete response (CR) or maintained CR were observed in 2 models in ADCE-010 and ADCE-011 groups, respectively.

Conclusions: uPARAP (MRC2) is highly expressed in most osteosarcoma samples, which makes it a viable target for respective antigen targeting ADC therapies. Three uPARAP (MRC2) targeting ADCs showed antitumor activities in osteosarcoma preclinical models which warrant further investigation of uPARAP targeting ADC therapies for osteosarcoma.

Citation Format: Yifei Wang, Wendong Zhang, Zhongting Zhang, Xiangjun Tian, Rossana Lazcano, Pooja Hingorani, Michael Roth, Jonathan Gill, Douglas Harrison, Zhaohui Xu, Jing Wang, Niels Behrendt, Christoffer F. Nielsen, Lars H. Engelholm, Richard Gorlick. Preclinical evaluation of uPARAP (MRC2) antibody-drug conjugates (ADCE-003,010,011) in osteosarcoma pdx models [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2022; 2022 Apr 8-13. Philadelphia (PA): AACR; Cancer Res 2022;82(12_Suppl):Abstract nr 2016.

Impact of probiotic Limosilactobacillus reuteri DSM 17938 on amino acid metabolism in the healthy newborn mouse

We studied the effect of feeding a single probiotic Limosilactobacillus reuteri DSM 17938 (LR 17938) on the luminal and plasma levels of amino acids and their derivatives in the suckling newborn mouse, using gas chromatography and high-performance liquid chromatography. We found that LR 17938 increased the relative abundance of many amino acids and their derivatives in stool, while it simultaneously significantly reduced the plasma levels of three amino acids (serine, citrulline, and taurine). Many peptides and dipeptides were increased in stool and plasma, notably gamma-glutamyl derivatives of amino acids, following ingestion of the LR 17938. Gamma-glutamyl transformation of amino acids facilitates their absorption. LR 17938 significantly upregulated N-acetylated amino acids, the levels of which could be useful biomarkers in plasma and warrant further investigation. Specific fecal microbiota were associated with higher levels of fecal amino acids and their derivatives. Changes in luminal and circulating levels of amino acid derivatives, polyamines, and tryptophan metabolites may be mechanistically related to probiotic efficacy.

Comprehensive surfaceome profiling to identify and validate novel cell-surface targets in osteosarcoma

Immunoconjugates targeting cell-surface antigens have demonstrated clinical activity to enable regulatory approval in several solid and hematologic malignancies. We hypothesize that a rigorous and comprehensive surfaceome profiling approach to identify osteosarcoma-specific cell-surface antigens can similarly enable development of effective therapeutics in this disease. Herein, we describe an integrated proteomic and transcriptomic surfaceome profiling approach to identify cell-surface proteins that are highly expressed in osteosarcoma but minimally expressed on normal tissues. Using this approach, we identified targets that are highly expressed in osteosarcoma. Three targets, MT1-MMP, CD276, and MRC2, were validated as overexpressed in osteosarcoma. Further, we tested BT1769, an MT1-MMP-targeted Bicycle toxin conjugate, in osteosarcoma PDX models. The results showed BT1769 had encouraging anti-tumor activity, high affinity for its target and a favorable pharmacokinetic profile. This confirms the hypothesis that our approach identifies novel targets with significant therapeutic potential in osteosarcoma.

[Etiology, diagnosis and treatment of infraoccluded primary second molars]

Infraocclusion is a phenomenon that the relative occlusal growth of a tooth stops after the period of active eruption and then the tooth becomes depressed below the occlusal plane. Infraocclusion occurred more commonly in children and the mostly affected teeth were the primary mandibular second molars. The occlusal problem caused by infraocclusion may progressively worsen with age. This review summarizes the etiology, diagnosis and treatment of infraoccluded second primary molars, so as to provide reference for the dental clinicians.

[Effects of eye exercises on axial eye elongation in junior students]

Objective: To evaluate the association between the eye exercises and one-year axial eye elongation in grade 7 students in Beijing. Methods: Sampling was performed using a multistage random cluster approach, and 1 443 students of grade 7 were selected from 9 middle schools in 6 districts for the baseline survey. Data were collected by questionnaires and axial length measurement. Multiple linear regression analysis was used to evaluate the association between eye exercises and excessive axial eye elongation. Results: Among 1 197 (82.95%) students with complete information, the median (Q_R) age was 12.00 (1.00) years old, girls accounted for 44.28%, and the median (Q_R) axial eye elongation was 0.22 (0.18) mm. In the multiple linear regression analysis, the frequency of eye exercises was significantly correlated with excessive axial eye elongation in boys (β=-0.135, 95%CI:-0.253--0.018) but not in girls (β=-0.075, 95%CI:-0.207- 0.058) after adjusting for sex, age, body height, the number of myopic parents, time spent outdoors and time spent on reading and writing outside class; while the seriousness of eye exercises was not significantly associated with axial eye elongation in boys (β=-0.028, 95%CI: -0.114-0.058) and girls (β=-0.035, 95%CI: -0.134-0.064). Conclusion: The increased frequency of eye exercises is beneficial to control the axial eye elongation in boys in Beijing.

[Clinicopathological features of malignant mixed mesodermal tumor: analysis of 50 cases]

Objective: To investigate the clinicpathological, immunohistochemical and molecular genetic features of malignant mixed mesodermal tumor (MMMT) in the female reproductive system. Methods: To analyze its histopathological characteristics, we performed a retrospective review of the MMMT cases diagnosed at PLA General Hospital, Beijing, China during 2005-2019 using its surgical and pathological databases. EnVision immunohistochemical staining was used to detect the expression of ER, PR, p16, p53 and MMR proteins. Results: Fifty cases were conformed to the diagnosis, including 29 cases originated in the uterus, 16 cases in ovary, 4 cases of synchronous occurrence in uterus and ovary, 1 case in cervix. The tumor was histologically composed of two components, namely carcinoma and sarcoma ones, with clear borderline or blend mutually. The proportion of cancer component in the whole tumor ranged from 5%-90%. The proportion of carcinoma was more than 50% in 76% of the cases, and less than 50% in 24% of cases, including 2 cases with<10% of carcinoma. In the cases of primary uterine MMMT, the main carcinoma type was high grade endometrioid carcinoma (55%, 16/29). In ovarian MMMT, the main carcinoma type was serous carcinoma (12/16), while that of cervical MMMT was squamous cell carcinoma. The others were clear cell carcinoma or the undifferentiated carcinoma. There was one carcinoma type in most cases, only 7 cases had two carcinoma types. Homologous sarcomas, including stromal sarcoma, leiomyosarcoma and high-grade spindle cell sarcomas, were more commonly found in uterine MMMT (72.4%, 21/29). While heterogenic sarcomas, including chondrosarcoma, osteosarcoma and rhabdomyosarcoma, were more commonly noted in ovarian MMMT (12/16) than MMMT of other sites. There were 10 cases that consisted of two types of sarcomas. The synchronous MMMT of uterus and ovary had similar morphology and the types of carcinoma and sarcoma. The tumor cells that spread or metastasized to lymph node, omentum, intestinal wall or skin were all carcinoma cells, and were morphologically consistent with the original tumors. Immunohistochemically, ER and PR were both negative (23/25 in uterine, 8/10 in ovarian tumors). p16 was strongly positive (11/11 in uterine tumors, and 6/6 in ovarian tumors), with similar expression patterns in the carcinoma and sarcoma components. p53 showed mutant-type staining (64%, 21/33) and expressed synchronously in carcinoma and sarcoma components. p53 mutation was found in 35% cases of endometrial carcinoma and 46.7% cases of non-endometrial carcinoma. p53 mutation was also found in only 31.8% cases of heterogenic sarcomas, but in 50% of non-heterogenic sarcomas. Twenty-eight cases (28/33, 85%) presented intact mismatch repair proteins, while 5 cases (5/33, 15%) presented deficient mismatch repair proteins. Conclusions: MMMT in female reproductive system is a rare high-grade biphasic tumor with complex and diverse morphology. The immunohistochemical features are characterized by negative ER/PR and strongly positive p16, mostly mutant p53 and proficient mismatch repair proteins. The patients with a high FIGO stage have worse prognosis.

P–420 uncomplicated oocyte donation pregnancies display elevated CD163 positive type 2 macrophage load in the decidua, which is associated with fetal-maternal HLA class II mismatches

Study question

Do quantity and composition of decidual macrophages differ between uncomplicated oocyte donation (OD) pregnancies and non-OD in vitro fertilization (IVF) pregnancies?

Summary answer

OD placentas show higher decidual CD163 positive fraction within the total macrophage population compared to non-OD IVF placentas.

What is known already

The embryo of an OD pregnancy is completely allogeneic to the mother, which may lead to a bigger challenge for the maternal immune system to tolerize the fetus compared to autologous pregnancies. Placental macrophages may be essential in maintaining a healthy pregnancy. Macrophages can be classified into different categories based on phenotype and characteristics, in which type 2 macrophages are thought to exhibit immune suppressive activity.

Study design, size, duration

This retrospective case-control study included patients who delivered in the Leiden University Medical Center between January 1st 2006 and July 1st 2016. A total of 42 pregnancies were enrolled in this study, conceived by uncomplicated singleton OD pregnancies (n = 25) or non-OD IVF pregnancies (n = 17). Medical records were reviewed and clinical data were collected. Placental tissue samples were collected for immunohistochemical staining and blood samples were collected for HLA typing.

Participants/materials, setting, methods

Placentas were collected and immunohistochemically stained for CD14 (pan-macrophage marker) and CD163 (type 2 macrophage marker). The extent of staining was quantitated by digital image analysis software. To assess mismatching, maternal and fetal DNA was typed for HLA-A, -B, C, -DRB1, and -DQB1.

Main results and the role of chance

A significantly lower percentage of CD14 positive staining was observed in the decidua basalis of OD pregnancies compared to non-OD IVF pregnancies (p = 0.030). Consequently, the CD163/CD14 ratio in OD group was higher than in non-OD IVF group (p = 0.243). In the parietalis, OD pregnancies demonstrated a significantly higher percentage of CD163+ staining (p = 0.040) and a significantly higher CD163/CD14 ratio (p = 0.032) compared to non-OD IVF group. The reproducibility of this quantitative analysis was found to be high. OD group was separated into a syngeneic group (number of mismatches lower than half of the antigens per HLA locus) and an allogeneic group (number of mismatches higher than half of the antigens per HLA locus). Significant differences of CD163+ and CD163/CD14 ratio were found in the decidua parietalis when comparing the HLA-classII-allogeneic OD group with the non-OD IVF group (p = 0.047). This difference was not found for the HLA-class-II-syngeneic OD group.

Limitations, reasons for caution

Our study only focused on decidua basalis and parietalis, no other locations in the placentas. Larger sample size might be needed to verify the association between macrophages and HLA mismatches.

Wider implications of the findings: To our knowledge, this study is the first to quantify a higher CD163 positive M2 macrophages load within the total decidual macrophages of uncomplicated OD pregnancy compared to non-OD IVF pregnancies.

Trial registration number

Not applicable