Background The intestinal flora is correlated with the occurrence of colorectal cancer. We evaluate a new predictive model for the non-invasive diagnosis of colorectal cancer based on intestinal flora to verify the clinical application prospects of the intestinal flora as a new biomarker in non-invasive screening of colorectal cancer. Methods Subjects from two independent Asian cohorts (cohort I, consisting of 206 colorectal cancer and 112 healthy subjects; cohort II, consisting of 67 colorectal cancer and 54 healthy subjects) were included. A probe-based duplex quantitative PCR (qPCR) determination was established for the quantitative determination of candidate bacterial markers. Results We screened through the gutMEGA database to identify potential non-invasive biomarkers for colorectal cancer, including Prevotella copri ( Pc ), Gemella morbillorum ( Gm ), Parvimonas micra ( Pm ), Cetobacterium somerae ( Cs ), and Pasteurella stomatis ( Ps ). A predictive model with good sensitivity and specificity was established as a new diagnostic tool for colorectal cancer. Under the best cutoff value that maximizes the sum of sensitivity and specificity, Gm and Pm had better specificity and sensitivity than other target bacteria. The combined detection model of five kinds of bacteria showed better diagnostic ability than Gm or Pm alone (AUC = 0.861, P < 0.001). These findings were further confirmed in the independent cohort II. Particularly, the combination of bacterial markers and fecal immunochemical test (FIT) improved the diagnostic ability of the five bacteria (sensitivity 67.96%, specificity 89.29%) for patients with colorectal cancer. Conclusion Fecal-based colorectal cancer-related bacteria can be used as new non-invasive diagnostic biomarkers of colorectal cancer. Simultaneously, the molecular biomarkers in fecal samples are similar to FIT, have the applicability in combination with other detection methods, which is expected to improve the sensitivity of diagnosis for colorectal cancer, and have a promising prospect of clinical application.
Objective: Total neoadjuvant chemoradiotherapy is one of the standard treatments for locally advanced rectal cancer. This study aims to investigate the safety and feasibility of programmed cell death protein 1 (PD-1) antibody combined with total neoadjuvant chemoradiotherapy in the treatment of locally advanced middle-low rectal cancer with high-risk factors. Methods: A descriptive cohort study was conducted. Clinicopathological data of 24 patients with locally advanced middle-low rectal cancer with high-risk factors receiving PD-1 antibody combined with neoadjuvant chemoradiotherapy in Gastrointestinal Cancer Center, Unit III, Peking University Cancer Hospital between January 2019 and April 2021 were retrospectively analyzed. Inclusion criteria: (1) rectal adenocarcinoma confirmed by pathology; patient age of ≥ 18 years and ≤ 80 years; (2) the distance from low margin of tumor to anal verge ≤ 10 cm under sigmoidoscopy; (3) ECOG performance status score 0-1; (4) clinical stage T3c, T3d, T4a or T4b, or extramural venous invasion (EMVI) (+) or mrN2 (+) or mesorectal fasciae (MRF) (+) based on MRI; (5) no evidence of distant metastases; (6) no prior pelvic radiation therapy, no prior chemotherapy or surgery for rectal cancer; (7) no systemic infection requiring antibiotic treatment and no immune system disease. Exclusion criteria: (1) anticipated unresectable tumor after neoadjuvant treatment; (2) patients with a history of a prior malignancy within the past 5 years, or with a history of any arterial thrombotic event within the past 6 months; (3) patients received other types of antitumor or experimental therapy; (4) women who were pregnant or breast-feeding; (5) patients with any other concurrent medical or psychiatric condition or disease; (6) patients received immunotherapy (PD-1 antibody). The neoadjuvant therapy consisted of three stages: PD-1 antibody (sintilimab 200 mg, IV, Q3W) combined with CapeOx regimen for three cycles; long-course intensity modulated radiation therapy (IMRT) with gross tumor volume (GTV) 50.6 Gy/CTV 41.8 Gy/22f; CapeOx regimen for two cycles after radiotherapy. After oncological evaluation following the end of the third stage of treatment, surgery or watch and wait would be carried out. Surgical safety, histopathological changes and short-term oncological outcome were analyzed. Results: There were 15 males and 9 females with a median age of 65 (47-78) years. Median distance from the lower margin of the tumor to the anal verge was 4 (3-7) cm. The median maximal diameter of the tumor was 5.1 (2.1-7.5) cm. Twenty patients were cT3, 4 were cT4, 8 were cN1, 5 were cN2a, 11 were cN2b. Ten cases were MRF (+) and 10 were EMVI (+). All the patients were mismatch repair proficient (pMMR). During the neoadjuvant treatment period, 6 patients (25.0%) developed grade 1-2 treatment-related adverse events, including 3 immune-related adverse events. As of April 30, 2021, 20 patients (83.3%, 20/24) had received surgical resection, including 19 R0 resections and 16 sphincter-preservation operations. Morbidity of postoperative complication was 25.0% (5/20), including 2 cases of Clavien-Dindo grade II (1 of anastomotic bleeding and 1 of pseudomembranous enteritis), 3 cases of grade I anastomotic stenosis. Pathological complete response (pCR) rate was 30.0% (6/20) and major pathological response rate was 20.0% (4/20). None of Ras/Raf mutants had pCR or cCR (0/5), while 6 of 17 Ras/Raf wild-type patients had pCR and 3 had cCR, which was significantly higher than that of Ras/Raf mutants (P<0.01). Nine of 16 patients with Ras/Raf wild-type and differentiated adenocarcinoma had pCR or cCR. Among other 4 patients without surgery, 3 patients preferred watch and wait strategy because their tumors were assessed as clinical complete response (cCR), while another one patient refused surgery as the tumor remained stable. After a median follow-up of 11 (6-24) months, only 1 patient with signet ring cell carcinoma had recurrence. Conclusions: PD-1 antibody combined with total neoadjuvant chemoradiotherapy in the treatment of locally advanced rectal cancer has quite good safety and histopathological regression results. Combination of histology and genetic testing is helpful to screen potential beneficiaries.目的: 探讨程序性细胞死亡蛋白1(PD-1)抗体联合全程新辅助治疗对高风险局部进展期中低位直肠癌患者应用的安全性和可行性。 方法: 采用描述性病例系列研究方法。回顾性分析2019年1月至2021年4月期间,在北京大学肿瘤医院胃肠肿瘤中心三病区24例接受PD-1联合全程新辅助放化疗的高风险局部进展期中低位直肠癌患者的临床资料。纳入标准:(1)经病理学确诊的直肠腺癌,患者年龄范围18~80岁;(2)内镜下肿瘤下缘距离肛缘≤10 cm;(3)美国东部肿瘤协作组(ECOG)体力状况评分0~1;(4)初始MRI局部分期为T(3)c、T(3)d、T(4)a和T(4)b,或壁外血管侵犯(EMVI)阳性,或mrN(2),或直肠系膜筋膜(MRF)阳性;(5)治疗前无明确远隔转移证据;(6)无盆腔放疗史、直肠癌手术史或化疗史;(7)不伴需抗生素治疗的全身性感染以及免疫系统疾病。排除标准:(1)预期新辅助治疗后肿瘤仍不可切除;(2)过去5年内罹患过其他可能影响患者结局的恶性肿瘤或过去6个月发生过动脉栓塞性疾病;(3)接受过其他类型的抗肿瘤或试验性治疗;(4)孕期或哺乳期女性;(5)合并有其他疾病或精神状态异常;(6)即往接受过抗PD-1抗体等免疫治疗的患者。新辅助治疗包括3个阶段,即PD-1抗体(信迪利单抗200 mg,静脉滴注,每3周1次)联合CapeOx方案(奥沙利铂+卡培他滨)3周期;长疗程放疗(调强放疗GTV 50.6 Gy/CTV 41.8 Gy/22 f);放疗结束后CapeOx方案化疗2周期。第3阶段治疗结束后经过肿瘤疗效评估,行手术治疗或选择等待观察。分析其手术安全性、病理组织学改变及近期肿瘤学结局。 结果: 24例患者中男性15例,女性9例,中位年龄65(47~78)岁,肿瘤下缘距离肛缘中位距离4(3~7)cm。肿瘤最大径中位值5.1(2.1~7.5)cm。cT(3)和cT(4)期分别为20例和4例;cN(1)、cN(2)a和cN(2)b期分别为8例、5例和11例。MRF阳性10例,EMVI阳性10例。所有患者均为错配修复蛋白阳性表达(pMMR)。新辅助治疗期间,6例(25.0%)发生了Ⅰ~Ⅱ级治疗相关不良事件,包括3例免疫相关不良事件。截至2021年4月30日,83.3%(20/24)的患者接受了手术治疗,19例为R(0)切除,16例接受保留肛门括约肌手术;术后并发症发生率为25.0%(5/20),包括2例Clavien-Dindo Ⅱ级(吻合口出血和伪膜性肠炎各1例),3例Ⅰ级吻合口狭窄。病理学完全缓解(pCR)比例为30.0%(6/20),主要病理学反应率为20.0%(4/20)。Ras/Raf突变者无一例出现pCR或cCR(0/5),17例Ras/Raf野生型患者中6例pCR,3例cCR,显著高于Ras/Raf突变型(P<0.01)。Ras/Raf野生型且为分化型腺癌的16例患者,9例达到pCR或cCR。4例未接受手术的患者中,3例为cCR,采取等待观察策略;1例为SD,因无法保肛拒绝手术。末次中位随访时间为11(6~24)个月,仅1例印戒细胞癌患者出现复发。 结论: PD-1抗体联合全程新辅助放化疗治疗局部进展期直肠癌,具有较好的安全性及组织病理学退缩结果。联合组织学及基因检测有助于筛选可能获益人群。.
Abstract Background: Despite a rapidly growing body of pertinent literature, what role the protein stimulator of interferon genes (STING) plays in colorectal cancer (CRC) remains unclear. We are committed to exploring whether STING can be adopted as an effective target and biomarker for CRC. Methods: STING expression was examined by immunohistochemistry to evaluate its association with clinicopathological factors. In addition, the effects of STING on various biological characteristics of CRC cells, such as proliferation, migration, invasiveness and drug resistance, were also studied. Gene set enrichment analysis was an indispensable tool to study the downstream mechanism of STING. Meanwhile, we explored the effect of STING on glucose uptake. Results: Our study suggested that the expression of STING was not only up-regulated in CRC, but also correlated with TNM stage and poor prognosis. Moreover, STING regulates cell migration, proliferation, invasiveness and drug resistance via mediating AMPK-mTOR pathway. Finally, we confirmed that STING regulates energy metabolism in CRC cells. Conclusions: STING may be a promising biomarker and a target for chemosensitization and inhibition of CRC progression.
BackgroundMost gastric cancers are diagnosed at an advanced or metastatic stage with poor prognosis and survival rate. Fatty acid 2-hydroxylase (FA2H) with high expression in stomach generates chiral (R)-2-hydroxy FAs ((R)-2-OHFAs) and regulates glucose utilization which is important for cell proliferation and invasiveness. We hypothesized that FA2H impacts gastric tumor growth and could represent a novel target to improve gastric cancer therapy.MethodsFA2H level in 117 human gastric tumors and its association with tumor growth, metastasis and overall survival were examined. Its roles and potential mechanisms in regulating tumor growth were studied by genetic and pharmacological manipulation of gastric cancer cells in vitro and in vivo.FindingsFA2H level was lower in gastric tumor tissues as compared to surrounding tissues and associated with clinicopathologic status of patients, which were confirmed by analyses of multiple published datasets. FA2H depletion decreased tumor chemosensitivity, partially due to inhibition of AMPK and activation of the mTOR/S6K1/Gli1 pathway. Conversely, FA2H overexpression or treatment with (R)-2-OHFAs had the opposite effects. In line with these in vitro observations, FA2H knockdown promoted tumor growth with increased level of tumor Gli1 in vivo. Moreover, (R)-2-OHFA treatment significantly decreased Gli1 level in gastric tumors and enhanced tumor chemosensitivity to cisplatin, while alleviating the chemotherapy-induced weight loss in mice.InterpretationOur results demonstrate that FA2H plays an important role in regulating Hh signaling and gastric tumor growth and suggest that (R)-2-OHFAs could be effective as nontoxic wide-spectrum drugs to promote chemosensitivity.FundGrants of NSF, NIH, and PAPD.
The mineralocorticoid receptor (MR) plays a central role in electrolyte homeostasis and in cardiovascular disease. We have previously reported a ligand-dependent N/C-interaction in the MR. In the present study we sought to fully characterize the MR N/C-interaction. By using a range of natural and synthetic MR ligands in a mammalian two-hybrid assay we demonstrate that in contrast to aldosterone, which strongly induces the interaction, the physiological ligands deoxycorticosterone and cortisol weakly promote the interaction but predominantly inhibit the aldosterone-mediated N/C-interaction. Similarly, progesterone and dexamethasone antagonize the interaction. In contrast, the synthetic agonist 9alpha-fludrocortisol robustly induces the interaction. The ability of the N/C interaction to discriminate between MR agonists suggests a subtle conformational difference in the ligand-binding domain induced by these agonists. We also demonstrate that the N/C interaction is not cell specific, consistent with the evidence from a glutathione-S-transferase pull-down assay, of a direct protein-protein interaction between the N- and C-terminal domains of the MR. Examination of a panel of deletions in the N terminus suggests that several regions may be critical to the N/C-interaction. These studies have identified functional differences between physiological MR ligands, which suggest that the ligand-specific dependence of the N/C-interaction may contribute to the differential activation of the MR that has been reported in vivo.
Population-based studies have demonstrated an association of single nucleotide polymorphisms close to the thyroid transcription factor forkhead box E1 (FOXE1) gene with thyroid cancer. The dysregulation of forkhead proteins is increasingly recognized to play a role in the development and progression of cancer. The objective of the study was to seek to identify novel mutations in FOXE1 in papillary thyroid cancer (PTC) and to assess the effect of these mutations on protein expression and transcriptional function on FOXE1 responsive promoters.The study was conducted at two tertiary referral hospitals. The coding region of FOXE1 was sequenced in tissue-derived DNA or RNA from 120 patients with PTC and 110 patients with multinodular goiter (MNG). In vitro studies were performed to examine the protein expression and transcriptional function of FOXE1 mutants. A molecular model of the forkhead domain (FHD) of FOXE1 was generated using the SWISS-MODEL online server with the three-dimensional structure of FOXD3 as a template.Three somatic missense mutations were detected in PTC resulting in the amino acid substitutions P54Q, K95Q, and L112F. One additional mutation was detected in a MNG (G140R). In vitro studies demonstrated marked impairment in transcriptional activation by all four FOXE1 mutants, which was not explained by differences in protein expression. Molecular modeling localized three of the mutations to highly conserved regions of the FHD.We have identified novel somatic mutations of FOXE1 in PTC. Mutational inactivation of FOXE1 is an uncommon event in thyroid tumors but may contribute to thyroid carcinogenesis and dedifferentiation in concert with other oncogenic drivers.