No abstract

Malignant glioma is the most common central nervous system tumor of adults and is associated with a significant degree of morbidity and mortality. Gliomas are highly invasive and respond poorly to conventional treatments. Gliomas, like other tumor types, arise from a complex and poorly understood sequence of genetic and epigenetic alterations. Epigenetic alterations leading to gene silencing, in the form of aberrant CpG island promoter hypermethylation and histone deacetylation, have not been thoroughly investigated in brain tumors, and elucidating such changes is likely to enhance our understanding of their etiology and provide new treatment options. We used a combined approach of pharmacologic inhibition of DNA methylation and histone deacetylation, coupled with expression microarrays, to identify novel targets of epigenetic silencing in glioma cell lines. From this analysis, we identified >160 genes up-regulated by 5-aza-2 ¶-deoxycytidine and trichostatin A treatment. Further characterization of 10 of these genes, including the putative metastasis suppressor CST6, the apoptosis-inducer BIK, and TSPYL5, whose function is unknown, revealed that they are frequent targets of epigenetic silencing in glioma cell lines and primary tumors and suppress glioma cell growth in culture. Furthermore, we show that other members of the TSPYL gene family are epigenetically silenced in gliomas and dissect the contribution of individual DNA methyltransferases to the aberrant promoter hypermethylation events. These studies, therefore, lay the foundation for a comprehensive understanding of the full extent of epigenetic changes in gliomas and how they may be exploited for therapeutic purposes. (Cancer Res 2006; 66(15): 7490-501)

PURPOSE We evaluated the role of oxaliplatin as adjuvant chemotherapy in patients with rectal cancer who received preoperative chemoradiotherapy (CRT) with fluoropyrimidine monotherapy and total mesorectal excision (TME). METHODS The ADORE trial (adjuvant oxaliplatin in rectal cancer) is a multicenter, randomized trial in patients with postoperative ypStage II (ypT3-4N0) or III (ypTanyN1-2) rectal cancer after fluoropyrimidine-based preoperative CRT and TME. Patients were randomly assigned (1:1) to receive adjuvant chemotherapy either with FL (fluorouracil 380 mg/m2 and leucovorin 20 mg/m2) or FOLFOX (oxaliplatin 85 mg/m2, leucovorin 200 mg/m2, and fluorouracil bolus 400 mg/m2 on day 1, fluorouracil infusion 2,400 mg/m2 for 46 hours). Stratification factors included ypStage and participating center. Primary end point was disease-free survival (DFS). RESULTS A total of 321 patients were enrolled between November 19, 2008, and June 12, 2012. Six-year DFS rates were 68.2% in the FOLFOX arm versus 56.8% in the FL arm, with a stratified hazard ratio of 0.63 (95% CI, 0.43 to 0.93; P = .018) by intention-to-treat analysis. In the subgroup analysis for DFS, FOLFOX was favorable versus FL in patients with ypStage III, ypN1b, ypN2, high-grade histology, minimally regressed tumor, and an absence of lymphovascular or perineural invasion. Six-year overall survival rate was 78.1% in the FOLFOX arm versus76.4% in the FL arm (hazard ratio, 0.73; 95% CI, 0.45 to 1.19; P = .21). In the subgroup analysis for OS, FOLFOX was favorable versus FL in patients with ypN2 and minimally regressed tumor. CONCLUSION Adjuvant FOLFOX improved DFS in patients with rectal cancer with ypStage II and III disease after preoperative CRT. Adjuvant FOLFOX may be considered on the basis of the postoperative pathologic stage in those who received preoperative CRT and TME.

We evaluated the efficacy and safety of avelumab, an anti-PD-L1 antibody, in patients with metastatic or unresectable colorectal cancer (mCRC) with mismatch repair deficiency (dMMR)/microsatellite instability-high (MSI-H) or POLE mutations. Materials and Methods In this prospective, open-label, multicenter phase II study, 33 patients with mCRC harboring dMMR/MSI-H or POLE mutations after failure of ≥ 1st-line chemotherapy received avelumab 10 mg/kg every 2 weeks. dMMR/MSI-H was confirmed with immunohistochemical staining (IHC) by loss of expression of MMR proteins or polymerase chain reaction (PCR) for microsatellite sequences. POLE mutation was confirmed by next-generation sequencing (NGS). The primary endpoint was the objective response rate (ORR) by Response Evaluation Criteria in Solid Tumors ver. 1.1. Results The median age was 60 years, and 78.8% were male. Thirty patients were dMMR/MSI-H and three had POLE mutations. The ORR was 24.2%, and all of the responders were dMMR/MSI-H. For 21 patients with MSI-H by PCR or NGS, the ORR was 28.6%. At a median follow-up duration of 16.3 months, median progression-free survival and overall survival were 3.9 and 13.2 months in all patients, and 8.1 months and not reached, respectively, in patients with MSI-H by PCR or NGS. Dose interruption and discontinuation due to treatment-related adverse events occurred in four and two patients, respectively, with no treatment-related deaths. Conclusion Avelumab displayed antitumor activity with manageable toxicity in patients with previously treated mCRC harboring dMMR/MSI-H. Diagnosis of dMMR/MSI-H with PCR or NGS could be complementary to IHC to select patients who would benefit from immunotherapy.

Analyzing cell-free DNA (cfDNA) as a source of circulating tumor DNA is useful for diagnosing or monitoring patients with cancer. However, the concordance between cfDNA within liquid biopsy and genomic DNA (gDNA) within tumor tissue biopsy is still under debate. To evaluate the concordance in a clinical setting, we enrolled 54 patients with metastatic colorectal cancer and analyzed their plasma cfDNA, gDNA from peripheral blood mononuclear cells (PBMC), and gDNA from available matched tumor tissues using ultra-deep sequencing targeting 10 genes (38-kb size) recurrently mutated in colorectal cancer. We first established a highly reliable cutoff value using reference material. The sensitivity of detecting KRAS hotspot mutations in plasma was calculated as 100%, according to digital droplet PCR. We could selectively detect clinically important somatic alterations with a variant allele frequency as low as 0.18%. We next compared somatic mutations of the 10 genes between cfDNA and genomic DNA from tumor tissues and observed an overall 93% concordance rate between the two types of samples. Additionally, the concordance rate of patients with the time interval between liquid biopsy and tumor tissue biopsy within 6 months and no prior exposure to chemotherapy was much higher than those without. The patients with KRAS mutant fragments in plasma had poor prognosis than those without the mutant fragments (33 months vs. 63 months; p<0.05). Consequently, the profiling with our method could achieve highly concordant results and may facilitate the surveillance of the tumor status with liquid biopsy in CRC patients.

Purpose: This study investigated the efficacy and safety of avelumab, an anti-programmed death ligand 1 (PD-L1) antibody, in patients with advanced hepatocellular carcinoma previously treated with sorafenib (NCT03389126). Patients and Methods: This is a single-arm, single center, phase II trial. Patients with Child-Pugh A score who had at least one measurable lesion were enrolled. Intravenous avelumab 10 mg/kg every 2 weeks was given until disease progression or unacceptable toxicity. The primary endpoint was objective response rate (ORR) according to RECIST v1.1. Secondary endpoints included time to progression (TTP), overall survival (OS), disease control rate (DCR), and safety. Results: A total of 30 patients were enrolled. After a median follow-up of 13.9 months, 27 progression events and 20 death events occurred. There was no complete response, three (10.0%) partial responses, and 19 patients (63.3%) with stable disease. ORR was 10.0% and DCR was 73.3%. The median TTP and OS was 4.4 and 14.2 months, respectively. PD-L1 expression did not affect avelumab response. Prior duration of sorafenib treatment, when dichotomized by the median 2.7 months, was associated with treatment outcome. TTP (6.5 vs. 1.8 months, P = 0.007) and OS (19.0 vs. 7.8 months, P = 0.006) were superior in patients with longer sorafenib duration. There was tendency of higher ORR (20.0% vs. 0.0%, P = 0.22) in those with longer sorafenib duration. Avelumab was well tolerated with seven grade 3 adverse events and no grade 4 adverse events. Conclusions: Avelumab showed moderate efficacy and was well tolerated in advanced hepatocellular carcinoma previously treated with sorafenib.

While obesity increases colorectal cancer incidence, there are inconsistent results in the prognostic role of obesity or body weight change on survival. This study investigated the prognostic impact of body weight and weight change in stage III or high risk stage II colon cancer patients. We used data from patients enrolled in the phase III AVANT trial. The AVANT trial investigated the efficacy of adding bevacizumab to standard adjuvant chemotherapy (FOFOX or XELOX). Weight change during the first 6 months of adjuvant chemotherapy was measured. Cox proportional hazard model was used to assess the prognostic influence of body weight and weight change. Among 3451 intention-to-treat population, body weight and weight change was measured in 3449 (99.9%) and 2455 (71.1%) patients, respectively. Among 2455 patients, 651 (26.5%) had weight gain over 5 kg and 179 (7.3%) had weight loss over 5 kg. Weight gain was more frequently observed in Asian and male. Neither baseline BMI nor weight change affected recurrence or survival in the Cox proportional hazard model.

In order to overcome, challenges involved in bringing NGS testing into routine clinical use, a centralized laboratory model was designed that could improve the NGS workflows, provide appropriate turnaround times and control costs with goal of enabling precision medicine.