β-Arrestins (Arrb) participate in the regulation of multiple signaling pathways, including Wnt/β-catenin, the major actor in human colorectal cancer initiation. To better understand the roles of Arrb ...in intestinal tumorigenesis, a reverse genetic approach (Arrb–/–) and in vivo siRNA treatment were used in ApcΔ14/+ mice. Mice with Arrb2 depletion (knockout and siRNA) developed only 33% of the tumors detected in their Arrb2-WT littermates, whereas Arrb1 depletion remained without significant effect. These remaining tumors grow normally and are essentially Arrb2–independent. Unsupervised hierarchical clustering analysis showed that they clustered with 25% of ApcΔ14/+;Arrb2+/+ tumors. Genes overexpressed in this subset reflect a high interaction with the immune system, whereas those overexpressed in Arrb2–dependent tumors are predominantly involved in Wnt signaling, cell adhesion, migration, and extracellular matrix remodeling. The involvement of Arrb2 in intestinal tumor development via the regulation of the Wnt pathway is supported by ex vivo and in vitro experiments using either tumors from ApcΔ14/+ mice or murine ApcMin/+ cells. Indeed, Arrb2 siRNAs decreased the expression of Wnt target genes in cells isolated from 12 of 18 tumors from ApcΔ14/+ mice. In ApcMin/+ cells, Arrb2 siRNAs completely reversed the increased Wnt activity and colony formation in soft agar induced by Apc siRNA treatment, whereas they did not affect these parameters in basal conditions or in cells expressing constitutively active β-catenin. We demonstrate that Arrb2 is essential for the initiation and growth of intestinal tumors displaying elevated Wnt pathway activity and identify a previously unsuspected molecular heterogeneity among tumors induced by truncating Apc mutations.
Sporadic or hereditary colorectal cancer (CRC) with microsatellite instability (MSI) is frequently characterized by inflammatory lymphocytic infiltration and tends to be associated with a better ...outcome than microsatellite stable (MSS) CRC, probably reflecting a more effective immune response. We investigated inflammatory mechanisms in 48 MSI CRCs and 62 MSS CRCs by analyzing: (1) the expression of 48 cytokines using Bio-Plex multiplex cytokine assays, and (2) the in situ immune response by immunohistochemical analysis with antibodies against CD3 (T lymphocytes), CD8 (cytotoxic T lymphocytes), CD45RO (memory T lymphocytes), T-bet (Th1 CD4 cells), and FoxP3 (regulatory T cells). MSI CRC exhibited significantly higher expression of CCL5 (RANTES), CXCL8 (IL-8), CXCL9 (MIG), IL-1β, CXCL10 (IP-10), IL-16, CXCL1 (GROα), and IL-1ra, and lower expression of MIF, compared with MSS CRC. Immunohistochemistry combined with image analysis indicated that the density of CD3
+
, CD8
+
, CD45RO
+
, and T-bet
+
T lymphocytes was higher in MSI CRC than in MSS CRC, whereas the number of regulatory T cells (FoxP3
+
) was not statistically different between the groups. These results indicate that MSI CRC is associated with a specific cytokine expression profile that includes CCL5, CXCL10, and CXCL9, which are involved in the T helper type 1 (Th1) response and in the recruitment of memory CD45RO
+
T cells. Our findings highlight the major role of adaptive immunity in MSI CRC and provide a possible explanation for the more favorable prognosis of this CRC subtype.
Circulating tumor DNA (ctDNA) is reported to be promising in localized colorectal cancer (CRC). The present study aimed to retrospectively evaluate the impact of ctDNA in patients with a resected ...stage II CRC from the PROGIGE 13 trial with available paired tumor and blood samples. A group of recurrent patients were matched one-to-one with nonrecurrent patients according to sex, tumor location, treatment sequence, and blood collection timing. CtDNA was analyzed by digital PCR according to NGS of tumors. Disease-free survival (DFS) and overall survival (OS) were analyzed based on ctDNA, and the risks of recurrence and death were determined. A total of 134 patients were included, with 67 patients in each group. At least one alteration was identified in 115/134 tumors. Postoperative ctDNA was detected in 10/111 (9.0%) informative samples and was detected more frequently in the recurrent group (16.7% versus 1.8%; p = 0.02). The median DFS of ctDNA+ versus ctDNA- patients was 16.8 versus 54 months (p = 0.002), respectively, and the median OS was 51.3 versus 69.5 months (p = 0.03), respectively. CtDNA was associated with recurrence (ORa = 11.13, p = 0.03) and death (HRa = 3.15, p = 0.01). In conclusion, the presence of postoperative ctDNA is associated with both recurrence and survival in stage II CRC.
To identify microRNAs (miRNA) that predict response to anti-EGFR antibodies in patients with wild-type KRAS metastatic colorectal cancer (mCRC).
miRNA profiling was performed in a training set of 87 ...patients with mCRC refractory to chemotherapy treated with anti-EGFR antibodies. This included 33 fresh-frozen (FF) and 35 formalin-fixed paraffin-embedded (FFPE) samples retrospectively collected and 19 prospectively collected FF samples. An independent validation cohort consisting of 19 FF and 26 FFPE prospectively collected samples from patients with mCRC treated with anti-EGFR antibodies was used to confirm our findings.
After screening the expression of 1,145 miRNAs in FF samples from the training set, we identified that hsa-miR-31-3p expression level was significantly associated with progression-free survival (PFS). Statistical models based on miRNA expression discriminated between high and low risk of progression for both FF and FFPE samples. These models were confirmed in the validation cohort for both FF HR, 4.1; 95% confidence interval (CI), 1.1-15.3; P < 0.04 and FFPE samples (HR, 2.44; 95% CI, 1.1-5.4; P = 0.028). The percentage of variation of RECIST criteria in the validation series was significantly associated with the expression level of hsa-miR-31-3p (r(2) = 0.49; P = 0.0035) and risk status determined by hsa-miR-31-3p expression level (P = 0.02, Kruskal-Wallis rank test). Nomograms were built and validated to predict PFS-depending on hsa-miR-31-3p expression level. Following in vitro studies, we identified 47 genes regulated by hsa-miR-31-3p.
Hsa-miR-31-3p seems to be a new mCRC biomarker whose expression level allows for the identification of patients with wild-type KRAS mCRC who are more likely to respond to anti-EGFR therapy.
This document is a summary of the French Intergroup guidelines regarding the management of appendicular epithelial tumors (AT) and pseudomyxoma peritonei (PMP) published in March 2020, available on ...the website of the French Society of Gastroenterology (SNFGE) (www.tncd.org).
All French medical societies specialized in the management of AT and PMP collaboratively established these recommendations based on literature until December 2019 and the results of a Delphi vote carried out by the Peritoneal Surface Oncology Group International experts, and graded into 4 categories (A, B, C, Expert Agreement) according to their level of evidence.
AT and PMP are rare but represent a wide range of clinico-pathological entities with several pathological classification systems and different biological behaviors. Their treatment modalities may vary accordingly and range from simple surveillance or laparoscopic appendectomy to complete cytoreductive surgery (CRS) with hyperthermic intraperitoneal chemotherapy (HIPEC) and / or systemic chemotherapy. The prognosis of these neoplasms may also largely vary according to their pathological grade and spreading at diagnosis or during the follow-up. Given the rarity of certain situations, the therapeutic strategy adapted to each patient, must be discussed in a specialized multidisciplinary meeting after a specialized pathological and radiological pre-therapeutic assessment and a clinical examination by a surgeon specializing in the management of rare peritoneal malignancies.
These recommendations are proposed to achieve the most beneficial strategy in a daily practice as the wide range and the rareness of these entities renders their management challenging. These guidelines are permanently being reviewed.
Background.
Triplet chemotherapy has demonstrated manageable toxicities and a favorable response rate. The addition of cetuximab to chemotherapy can increase treatment efficacy. We evaluated the ...efficacy and safety of cetuximab plus 5‐fluorouracil, leucovorin, irinotecan, and oxaliplatin (FOLFIRINOX), the ERBIRINOX regimen, as first‐line treatment in patients with unresectable metastatic colorectal cancer (mCRC).
Patients and Methods.
In a phase II study, treatment consisted of weekly cetuximab plus biweekly. Treatment was continued for a maximum of 12 cycles and tumor response was evaluated every four cycles. The primary efficacy criterion was the complete response (CR) rate.
Results.
From April 2006 to April 2008, 42 patients were enrolled. The median age was 60 years (range, 32–76 years). The median duration of treatment was 5.2 months (range, 0.7–8.5 months), and a median of nine cycles was given per patient (range, 1–12 cycles). Five patients (11.9%) showed a CR, with a median duration of 23.1 months (95% confidence interval CI, 10.8–39.7 months). The objective response rate was 80.9% (95% CI, 65.9%–91.4%). The median overall and progression‐free survival times were 24.7 months (95% CI, 22.6 months to not reached) and 9.5 months (95% CI, 7.6–10.4 months), respectively. The most frequent grade 3–4 adverse events were diarrhea (52%), neutropenia (38%), and asthenia (32%).
Conclusion.
The ERBIRINOX regimen appears to be effective and feasible in first‐line treatment of mCRC patients. These promising results led us to initiate a multicenter, randomized, phase II trial (Research Partnership for Digestive Oncology PRODIGE 14) in patients with potentially resectable mCRC.
摘要
背景. 三联化疗毒性反应容易处置、缓解率良好。化疗中添加西妥昔单抗可提高有效性。本研究评估西妥昔单抗联合5‐氟尿嘧啶+甲酰四氢叶酸+伊立替康+奥沙利铂（FOLFIRINOX）即ERBIRINOX方案一线治疗无法切除的转移性结直肠癌（mCRC）的有效性和安全性。
患者和方法. II期研究的治疗方案为西妥昔单抗每周1次+每2周1次。最长疗程为12个周期，每4个周期评估一次肿瘤缓解情况。主要有效性标准是完全缓解（CR）率。
结果. 2006年4月∼2008年4月，入组42例患者。中位年龄为60岁（32∼76岁）。中位疗程为5.2个月（0.7∼8.5个月），每例患者接受中位9个周期（1∼12周期）。5例（11.9%）患者获得CR，中位疗程为23.1个月95%可信区间（CI）：10.8∼39.7个月。客观缓解率为80.9%（95% CI：65.9%∼91.4%），中位总生存期和无进展生存期分别为24.7个月（95% CI：22.6个月∼持续存活）和9.5个月（95% CI：7.6∼10.4个月）。最常见的3∼4级不良事件为腹泻（52%）、中性粒细胞减少（38%）和乏力（32%）。
结论. ERBIRINOX方案似乎可为治疗mCRC患者的有效且可行的一线方案。该可喜的结果促使我们在有望手术治疗的mCRC患者中进行多中心II期随机试验 （Research Partnership for Digestive Oncology）PRODIGE 14。
The efficacy and safety of cetuximab plus 5‐fluorouracil, leucovorin, irinotecan, and oxaliplatin chemotherapy were evaluated as first‐line treatment for patients with unresectable metastatic colorectal cancer.
Gastric or gastro-oesophageal junction (GEJ) adenocarcinomas present poor overall survival (OS). First-line chemotherapy regimen for patients with HER2-negative tumours is based on a doublet or ...triplet of fluoropyrimidine plus platinum salt ± taxane. Second-line chemotherapy (Docetaxel or Irinotecan) improves OS which nonetheless remains poor (around 5 months). The first results of immune checkpoint inhibitors (anti-PD-1) combined with chemotherapy in metastatic gastric and GEJ cancers were discordant in recent phase III trials. Data on dual-blockade (anti-PD-L1 or anti-PD-1 plus anti-CTLA-4) plus chemotherapy are lacking.
DURIGAST is a randomised, multicenter, non-comparative, phase II study, evaluating safety and efficacy of FOLFIRI plus Durvalumab (anti-PD-L1) versus FOLFIRI plus Durvalumab and Tremelimumab (anti-CTLA-4) as second-line treatment of advanced gastric and GEJ adenocarcinoma. The primary objective is the rate of patients alive and without progression at 4 months. The main inclusion criteria are: patients with advanced gastric or GEJ adenocarcinoma, pre-treated with fluoropyrimidine + platinum salt ± taxane. Due to a lack of data on FOLFIRI, Durvalumab and Tremelimumab combination, a 2-step safety run-in phase has been performed before the randomised phase II. The safety run-in phase did not show any safety issue and the randomised phase II starts in September 2020.
Patients with metastatic colorectal cancer suffer from disease relapse mainly due to cancer stem cells (CSC). Interestingly, they have an increased level of blood progastrin, a tumor-promoting ...peptide essential for the self-renewal of colon CSCs, which is also a direct β-catenin/TCF4 target gene. In this study, we aimed to develop a novel targeted therapy to neutralize secreted progastrin to inhibit Wnt signaling, CSCs, and reduce relapses.
Antibodies (monoclonal and humanized) directed against progastrin were produced and selected for target specificity and affinity. After validation of their effectiveness on survival of colorectal cancer cell lines harboring B-RAF or K-RAS mutations, their efficacy was assessed
and
, alone or concomitantly with chemotherapy, on CSC self-renewal capacity, tumor recurrence, and Wnt signaling.
We show that anti-progastrin antibodies decrease self-renewal of CSCs both
and
, either alone or in combination with chemotherapy. Furthermore, migration and invasion of colorectal cancer cells are diminished; chemosensitivity is prolonged in SW620 and HT29 cells and posttreatment relapse is significantly delayed in T84 cells, xenografted nude mice. Finally, we show that the Wnt signaling activity
is decreased, and, in transgenic mice developing Wnt-driven intestinal neoplasia, the tumor burden is alleviated, with an amplification of cell differentiation in the remaining tumors.
Altogether, these data show that humanized anti-progastrin antibodies might represent a potential new treatment for K-RAS-mutated colorectal patients, for which there is a crucial unmet medical need.
.
DNA microarray technology enables investigators to measure the expression of several 1000 mRNA species simultaneously in a biological specimen. However, the reliability of the microarray technology ...to detect transcriptional differences representative of the original samples is affected by the quality of the extracted RNA. Thus, it is of critical importance to standardize sample-handling protocols and to perform a quality assessment of RNA preparations. In this report, 59 human tissue samples were used to evaluate the relationships between RNA quality and gene expression. From Affymetrix
® GeneChip
® array data analysis of these samples, we compared the performance of the 28S/18S ratio, two computer methods (RIN and degradometer) and our in-house RNA quality scale (RQS) in assessing RNA quality. The optimal RNA reliability threshold was determined for each method using statistical discrimination measures. We showed that RQS, RIN and degradometer have a similar capacity to detect reliable RNA samples whereas the 28S/18S ratio leads to a misleading categorization. Furthermore, we developed a new approach, based on clustering analyses of full chip expression, to control RNA quality after hybridization experiments. The combination of these methods, allowing monitoring of RNA quality prior to and after the hybridization experiments, ensured reliable and reproducible microarray data.
Abstract Introduction This document is a summary of the French Intergroup guidelines regarding the management of rectal adenocarcinoma published in February 2016. Method This collaborative work, ...under the auspices of most of the French medical societies involved in the management of rectal cancer, is based on the previous guidelines published in 2013. Recommendations are graded into 3 categories according to the level of evidence of data found in the literature. Results In agreement with the ESMO guidelines (2013), non-metastatic rectal cancers have been stratified in 4 risk groups according to endoscopy, MRI or endorectal-ultrasonography. Locally-advanced tumors are limited to groups 3 and 4 (T3 ≥4 cm or T3c–d or N1-2 or T4). These tumors are usually treated using neoadjuvant treatment and total proctectomy (TME). Adjuvant treatment depends on the pathological findings. Very early (group 1) or early (group 2) tumors are managed mainly by surgery, and organ preservation may be an option in selected cases. For metastatic tumors, the recommendations are based on less robust evidence and chemotherapy plays a major role. Conclusion Such recommendations are constantly being optimized and each individual case must be discussed within a Multi-Disciplinary Team.
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