At the 2024 Annual Meeting of the American Society of Clinical Oncology (ASCO), multiple research achievements in the field of colorectal cancer were announced. This article summarizes and interprets the research results related to colorectal cancer from the perspectives of local treatment progress, immunotherapy progress, targeted therapy, neoadjuvant therapy and surgery, and explores the hot spots, problems, and future directions of colorectal cancer treatment.

Objective To investigate the efficacy and safety of intravenous thrombolysis with low-dose and standard-dose recombinant tissue plasminogen activator(rt-PA)in the elderly patients(aged over 80 years)with acute ischemic stroke(AIS).Methods A total of 201 elderly patients with AIS treated at Tianjin Fourth Central Hospital from February 2019 to February 2023 were prospectively included and randomly assigned to the rt-PA low-dose group(n=93,0.6 mg/kg)and rt-PA standard-dose group(n=108,0.9 mg/kg).The incidence of intra-cranial hemorrhage,symptomatic intracranial hemorrhage,fatal intracranial hemorrhage,neurologic deterioration within 7 days and mortality within 90 days were observed to evaluate the safety.The neurologic improvement rate and good prognosis rate at 90 days were used to evaluate the effectiveness.A stratified analysis of 90-day outcomes was performed based on stroke severity and age.Results The incidence of intracranial hemorrhage,symptomatic intracranial hemorrhage and fatal intracranial hemorrhage within 7 days in rt-PA low-dose group was lower than that in rt-PA standard-dose group(P＜0.05).There were no statistically significant differences between the two groups concerning the residual safety index and the effectiveness index.The 90-day good prognosis rate of moderate stroke sub-group and of≥90 years of age sub-group in rt-PA low-dose group were both higher than that of rt-PA standard-dose group(P＜0.05).Conclusions For AIS patients with moderate stroke and aged over 90 years,intravenous thrombolytic therapy with rt-PA 0.6 mg/kg is recommended.

Endosomal TLRs (TLR3/7/8/9) are highly analogous innate immunity sensors for various viral or bacterial RNA/DNA molecular patterns. Among them, TLR7, in particular, has been suggested to be a target for various inflammatory disorders and autoimmune diseases including systemic lupus erythematosus (SLE); but few small-molecule inhibitors with elaborated mechanism have been reported in literature. Here, we reported a well-characterized human TLR7-specific small-molecule inhibitor, TH-407b, with promising potency and negligible cytotoxicity through a novel binding mechanism. Notably, TH-407b not only effectively inhibited TLR7-mediated pro-inflammatory signaling in a variety of cultured cell lines but also demonstrated potent inflammation suppressing activities in primary peripheral blood mononuclear cells (PBMCs) derived from SLE patients. Furthermore, TH-407b showed prominent efficacy in vivo, improved survival rate and ameliorated symptoms of SLE model mice. To obtain molecular insights into the TH-407b derivatives' inhibition mechanism, we performed the structural analysis of TLR7/TH-407b complex using cryogenic electron microscopy (cryo-EM) method. As an atomistic resolution cryo-EM structure of the TLR family, it not only of value to facilitate structure-based drug design, but also shed light to methodology development of small proteins using EM. Significantly, TH-407b has unveiled an inhibition strategy for TLR7 via stabilizing its resting/inactivated state. Such a resting state could be generally applicable to all TLRs, rendering a useful method for targeting this group of important immunological receptors.

Abstract Astragalus polysaccharides(APS), as one of the main active components of Astragali Radix, a traditional famous tonic drug in China, has good pharmacological effects in regulating immunity and anti-oxidation. In recent years, with the success of PD-1/PD-L1 inhibitors and anti-CTLA-4 drugs in cancer treatment, immunotherapy has truly become one of the main clinical anti-tumor treatment methods. Aiming at the characteristics of tumor immune escape and tumor microenvironment change, this paper explores the clinical potential of APS as an anti-tumor adjuvant drug, and summarizes the role and mechanism of APS in inhibiting tumor immune escape, regulating tumor microenvironment, and improving immune function. To summarize and analyze the immune regulation of APS on various tumors in order to provide an objective basis for APS as a clinical anti-tumor adjuvant drug.

Objective:To evaluate the efficacy and safety of radiofrequency introduction of L-vitamin C in patients with melasma.Methods:From March to June 2019, 20 patients with melasma were admitted to the Department of Dermatology, the Seventh Medical Center of PLA General Hospital, including 19 females and 1 male, aged 30-60 years, with an average age of 43.5 years. All patients were treated with 22 percent of L-vitamin C once a week, a total of 8 times of treatment and followed up for 12 weeks. Each subject was assessed with standardized clinical photo, skin tests (VISIA skin image analyzer and CK multifunctional skin tester) and patient self-assessment. In addition, the adverse reactions were recorded.Results:Physician evaluation and patient self-evaluation showed that skin symptoms were improved obviously after treatment. 90% of the subjects thought that all of the skin moisture, pores, fine lines, glossiness, and color spots were improved after 12 weeks. The skin texture, ultraviolet stain and the brown spots which were detected with VISIA skin image analyzer were all improved after one week and one month. Difference was statistically significant ( P<0.05). Skin glossiness was significantly improved, skin moisture content increased and melanin decreased, which were detected with CK multifunctional skin tester. The differences were statistically significant ( P<0.05). But there was no significant change in transdermal water loss and red pigment index ( P>0.05). Conclusions:22% L-vitamin C can be used to treat melasma and improve photoaging safely without affecting skin barrier function.

Objective:To study the combined use of neoadjuvant chemotherapy and immunotherapy in patients with borderline resectable pancreatic cancer.Methods:The clinical data of patients with pancreatic cancer who were planned to undergo perioperative treatment before surgical treatment at the Fifth Medical Center of PLA General Hospital from January 2019 to June 2021 were retrospectively studied. Of 22 patients with pancreatic cancer, there were 10 males and 12 females, aged (56.0±10.2) years old. Preoperative treatment with chemotherapy (nab-paclitaxel and S-1, AS) and immunotherapy regimen before surgery were given. The baseline characteristics, treatment efficacy, surgical pathology and prognosis were analyzed.Results:Of 22 patients who were treated with neoadjuvant chemotherapy combined with programmed death-1 (PD-1) monoclonal antibody, 11 patients (50%) had tumors in the head, neck and uncinated process of pancreas. On radiographic assessment, one patient achieved CR (4.5%, 1/22), 9 patients PR (40.9%, 9/22), and 11 patients SD (50.0%, 11/22). All patients subsequently underwent R 0 resection. The postoperative pTNM staging showed 91% (20/22) of patients were in stage IA-IIB, 31.8% (7/22) of patients had pT2, 63.6% (14/22) had N0, and 1 patient had pCR. Thirteen patients (54.2%, 13/22) received postoperative adjuvant therapy. The median recurrence-free survival (RFS) was 6.4 months and the median time to progression (TTP) was 12.8 months. The median overall survival of patients was not reached. Postoperative pathology TNM staging IIA to III ( HR=3.63, 95% CI: 1.18-11.20, P=0.025) and postoperative pathology T2-3 stage ( HR=2.02, 95% CI: 1.01-5.05, P=0.049) were significantly associated with RFS. Postoperative pathology TNM stages IIA to III ( HR=2.39, 95% CI: 1.04-5.50, P=0.041) and postoperative pathology T2-3 stage ( HR=2.53, 95% CI: 1.26-5.09, P=0.009) were significantly associated with TTP. Conclusion:AS combined with PD-1 monoclonal antibody showed good efficacy as a neoadjuvant therapy for patients with borderline-resectable pancreatic cancer.

Objective To investigate the effect and mechanism of miR-885-3p on the radiosensitivity of colorectal cancer cell HT-29. Methods The expression of miR-885-3p in HT-29 cells irradiated with different doses (0, 2, 4, 6, 8 Gy) of X-rays was detected by qPCR. The effect of miR-885-3p in modulating cell radiosensitivity was assessed in HT-29 cells with miR-885-3p overexpression. Bioinformatics prediction and dual luciferase reporter gene assay were employed to identify the direct target gene of miR-885-3p. Relationship between miR-885-3p and target gene tyrosine kinase 1 (AKT1) was investigated via regulation of miR-885-3p expression. The effect of AKT1 on radiosensitivity in HT-29 cells was evaluated through knockdown AKT1. The effect of AKT1 on miR-885-3p-induced radiosensitivity was detected by co-transferring miR-885-3p and AKT1 gene into HT-29 cells. Results miR-885-3p expression was up-regulated in radiation-induced HT-29 cells (F=46. 64, P<0. 05). Over-expression of miR-885-3p and knockdown of AKT1 enhanced cell radiosensitization by inhibiting survival and promoting apoptosis (t=12. 33, 12. 95, P <0. 05) with SER of 1. 602 and 1. 946, respectively. Inhibition of miR-885-3p promoted radioresistance by increasing cell survival and inhibiting apoptosis (t=11. 94, P<0. 05) with a SER of 0. 839. AKT1 is a target gene downstream of miR-885-3p, overexpression of AKT1 reversed the effect of miR-885-3p on cell radiosensitivity with a SER of 0. 680. Conclusions miR-885-3p can enhance the radiosensitivity of colorectal cancer HT-29 cells by directly targeting AKT1, which provides a target for improving the radiosensitivity of clinical colorectal cancer.

Objective To induce fluconazole resistance in T.asahii by culture in medium containing increasing concentrations of fluconazole,and to evaluate the stability of the induced resistance.Methods Two T.asahii strains with a highest sensitivity to fluoconazole,including a clinical isolate CBS2479 (minumum inhibitory concentration (MIC) =0.25 μg/ml) and an environmental isolate CBS8904 (MIC =1.5 μg/ml),were selected from 11 T.asahii strains stored in the laboratory of the Department of Dermatology,General Hospital of Beijing Military Region.Both strains were respectively and serially subcultured in potato dextrose agar (PDA) medium containing growing concentrations of fluconazole (from 0.5 MIC to 256 μg/ml).E-test was performed to evaluate the susceptibility of T.asahii to fluconazole after each passage.To evaluate the stability of fluconazole resistance,the T.asahii isolates with induced resistance (MIC ＞ 256 μg/ml) were serially subcultured in drug-free PDA medium,and drug susceptibility assay was performed after each subculture.Results After serial culture in PDA medium containing fluconazole,high level of fluconazole resistance (MIC ＞ 256 μg/ml) developed in both of the fluconazole-susceptible T.asahii strains CBS2479 and CBS8904.The MIC value of fluconazole remained unchanged in the fluconazole-resistant strain CBS2479R,but gradually decreased to 64 μg/ml in the other resistant strain CBS8904R after 18-day culture in fluconazole-free PDA medium.Conclusions Fluconazole resistance can be induced in T.asahii strains from different origins by serial culture in medium containing growing concentrations of fluconazole,and the stability of the induced fluconazole resistance varies between strains of different origins.

Objective To determine the effect of interferon-gamma (IFN-γ) on the phagocytosis and killing activity of a murine macrophage cell line RAW264.7 against T.asahii,and to estimate the possibility of treating T.asahii infection with IFN-γγ.Methods T.asahii was cultured with or without the presence of different concentrations (10,100,1000 U/ml) of IFN-γfor 18 hours followed by the incubation with RAW264.7 cells for different durations.After additional culture for 45 minutes,the number of T.asahii cells phagocytosed by RAW264.7 cells was counted under an inverted microscope,and the rate of phagocytosis was calculated.The number of colony forming units of T.asahii per milliliter (cfu/ml) was counted after 4-hour additional culture and the growth inhibition rate was determined.Data were processed by the SPSS 16.0 software,and comparisons of parameters between these groups were done by Bonferroni method and analysis of variance after homogeneity test of variance.Results The number of phagocytosed T.asahiicells was 25.12 ± 1.81,35.88 ± 3.56,52.12 ± 3.23,with the phagocytosis rate being 25.12％,35.88％ and 52.12％,respectively in RAW264.7 cells incubated with IFN-γ of 10,100,1000 U/ml,significantly different from that in untreated RAW264.7 cells (13.62 ± 2.39,13.62％,all P ＜ 0.01).The colony forming units of T.asahii per ml after incubation with untreated RAW264.7 cells differed significantly from those after incubation with IFN-γ (10,100,1000 U/ml)-treated RAW264.7 cells ((68.12 ± 3.39) × 500 vs.(58.62 ± 4.89) × 500,(45.50 ± 3.02) × 500 and (34.62 ± 4.24) × 500,all P＜0.01),with the growth inhibition rate being 25.21％,41.95％ and 55.83％ respectively for RAW264.7 cells incubated with IFN-γ of 10,100,1000 U/ml.Statistical differences were also observed in the killing activity between RAW264.7 cells incubated with different concentrations of IFN-γ (all P ＜ 0.01).Conclusion IFN-γ (10-1000 U/ml) may enhance the phagocytosis and killing activity of RAW264.7 cells against T.asahii in a concentration-dependent manner.

Objective To observe morphological characteristics and activity distribution of T. asahii biofilm. Methods The morphological characteristics of T. asahii biofilm were observed under an inverted microscope and scanning electron microscope, and activity was measured and quantitatively analyzed by 2,3-bis (2-methoxy-4-nitro-5-sulfophenyl)-5-[(phenylamino) carbonyl]-2H-tetrazo-lium hydroxide (XTT) assay and viable count, respectively. Spatial distribution of dead/vital cells, activity and thickness of biofilm at different layers were assessed under a confocal laser scanning microscope (CLSM) following double staining with FDA/PI. Results T. asahii formed a biofilm in vitro on the surface of polystyrene materials. Under a scanning microscope, the biofilm displayed a complex three-dimensional structure which composed of spores, pseudohy-pha and true hypha. As time prolonged, the activity and quantity of biofilm increased. The results of XTT assay were correlated with those of viable count (r = 0.94, P < 0.01). The activity was of no obvious difference between different layers of the biofilm. The thickness of biofilm varied from 14.3 μm to 31 μm. Conclusions The structure of T. asahii biofilm in vitro is more complex than that of planktonic T. asahii. The activity is of no significant difference between different layers of T. asahii biofilm.