The human organism coexists with its microbiota in a symbiotic relationship. These polymicrobial communities are involved in many crucial functions, such as immunity, protection against pathogens, and metabolism of dietary compounds, thus maintaining homeostasis. The oral cavity and the colon, although distant anatomic regions, are both highly colonized by distinct microbiotas. However, studies indicate that oral bacteria are able to disseminate into the colon. This is mostly evident in conditions such as periodontitis, where specific bacteria, namely Fusobacterium nucrelatum and Porphyromonas gingivalis project a pathogenic profile. In the colon these bacteria can alter the composition of the residual microbiota, in the context of complex biofilms, resulting in intestinal dysbiosis. This orally-driven disruption promotes aberrant immune and inflammatory responses, eventually leading to colorectal cancer (CRC) tumorigenesis. Understanding the exact mechanisms of these interactions will yield future opportunities regarding prevention and treatment of CRC.

Ribonucleotide reductase subunits M1 (RRM1) and M2 (RRM2) are involved in the metabolism of gemcitabine (2′,2′-difluorodeoxycytidine), which is used for the treatment of nonsmall cell lung cancer. The mRNA expression of RRM1 and RRM2 in tumours from lung adenocarcinoma patients treated with docetaxel/gemcitabine was assessed and the results correlated with clinical outcome. RMM1 and RMM2 mRNA levels were determined by quantitative real-time PCR in primary tumours of previously untreated patients with advanced lung adenocarcinoma who were subsequently treated with docetaxel/gemcitabine. Amplification was successful in 42 (79%) of 53 enrolled patients. Low levels of RRM2 mRNA were associated with response to treatment (P< 0.001). Patients with the lowest expression levels of RRM1 had a significantly longer time to progression (P=0.044) and overall survival (P=0.02) than patients with the highest levels. Patients with low levels of both RRM1 and RRM2 had a significantly higher response rate (60 vs 14.2%; P=0.049), time to progression (9.9 vs 2.3 months; P=0.003) and overall survival (15.4 vs 3.6; P=0.031) than patients with high levels of both RRM1 and RRM2. Ribonucleotide reductase subunit M1 and RRM2 mRNA expression in lung adenocarcinoma tumours is associated with clinical outcome to docetaxel/gemcitabine. Prospective studies are warranted to evaluate the role of these markers in tailoring chemotherapy.

Purpose: To evaluate the efficacy and the toxicity of front line FOLFOX4 combined with bevacizumab in patients with metastatsic CRC (mCRC). Patients and Methods: Chemotherapy-naïve patients with mCRC, received bevacizumab (5 mg/kg every 2 weeks d₁), oxaliplatin (85 mg/m² on d₁), leucovorin (200 mg/m²) on days 1 and 2 and 5-Fluorouracil (400 mg/m² as i.v. bolus and 600 mg/m² as 22 h i.v. continuous infusion on days 1 and 2) every 2 weeks. Results: Fifty three patients (46 with a PS 0–1) were enrolled. Complete and partial response was achieved in eight (15.1%) and 28 (52.8%) patients, respectively (ORR: 67.9%; 95% C.I.: 53.8%–92%); 11 (20.7%) patients had stable disease and six (11.3%) progressive disease. With a median follow up period of 13.5 months, time to tumor progression was 11 months while the median survival has not yet been reached; the probability of 1-, 2- and 3- year survival was 79.8%, 63.8% and 58.3%, respectively; Two patients relapsed during the follow up period. Eight (15%) patients underwent metastasectomy with R0 resections. Grade 3–4 neutropenia occurred in 15.1% of patients and one (1.9%) of them presented febrile neutropenia. Non-hematologic toxicity included grade 3 diarrhea (7.6%) and grade 2 and 3 neurotoxicity in 16.9 and 15.1% of patients, respectively. One (1.9%) patient presented pulmonary embolism and one (1.9%) cardiac ischaemia. There was one (1.9%) sudden death after the first cycle. Conclusion: The combination of FOLFOX4/bevacizumab appears to be highly effective, well tolerated and merits further evaluation in patients with mCRC.

Colorectal cancer (CRC) remains a major public health issue. The detection of parameters that affect CRC prognosis is of great significance. KRAS mutations, play a crucial role in tumorigenesis with a strong predictive value. KRAS-mutated stage-IV CRC patients gain no benefit of the anti-EGFR therapy. The KRAS G12C mutation subtype is under investigation for treatment regimens. The present study aimed to detect various RAS mutations in a cohort of 578 RAS-mutated CRC patients; 49% of them had de novo metastatic disease; 60% were male; 71.4% had left-sided tumors; and 94.6% had a good performance status. KRAS mutations were detected in 93.2% of patients, with KRAS G12D being the most common subtype (30.1%). KRAS mutations presented shorter progression-free (PFS) and overall survival (OS), compared with NRAS mutations, although not significantly (PFS: 13.8 vs. 18.5 months; p = 0.552; OS: 53.1 vs. 60.9 months; p = 0.249). KRAS G12D mutations presented better OS rates (p = 0.04). KRAS G12C mutation, even though not significantly, presented worse PFS and OS rates. KRAS exon 3 and 4 mutations presented different PFS and OS rates, although these were not significant. Concluding, KRAS G12D and G12C mutations lead to better and worst prognosis, respectively. Further studies are warranted to validate such findings and their possible therapeutic implication.

Hepatocellular carcinoma (HCC) is the second leading cause of cancer-related deaths, reflecting the aggressiveness of this type of cancer and the absence of effective therapeutic regimens. MicroRNAs have been involved in the pathogenesis of different types of cancers, including liver cancer. Our aim was to identify microRNAs that have both functional and clinical relevance in HCC and examine their downstream signaling effectors. MicroRNA and gene expression levels were measured by quantitative real-time PCR in HCC tumors and controls. A TargetScan algorithm was used to identify miR-9 downstream direct targets. A high-throughput screen of the human microRNAome revealed 28 microRNAs as regulators of liver cancer cell invasiveness. MiR-9, miR-21 and miR-224 were the top inducers of HCC invasiveness and also their expression was increased in HCC relative to control liver tissues. Integration of the microRNA screen and expression data revealed miR-9 as the top microRNA, having both functional and clinical significance. MiR-9 levels correlated with HCC tumor stage and miR-9 overexpression induced SNU-449 and HepG2 cell growth, invasiveness and their ability to form colonies in soft agar. Bioinformatics and 3′UTR luciferase analyses identified E-cadherin (CDH1) and peroxisome proliferator-activated receptor alpha (PPARA) as direct downstream effectors of miR-9 activity. Inhibition of PPARA suppressed CDH1 mRNA levels, suggesting that miR-9 regulates CDH1 expression directly through binding in its 3′UTR and indirectly through PPARA. On the other hand, miR-9 inhibition of overexpression suppressed HCC tumorigenicity and invasiveness. PPARA and CDH1 mRNA levels were decreased in HCC relative to controls and were inversely correlated with miR-9 levels. Taken together, this study revealed the involvement of the miR-9/PPARA/CDH1 signaling pathway in HCC oncogenesis.

The International Duration Evaluation of Adjuvant Chemotherapy (IDEA) aimed to investigate whether a 3 months (3M) of oxaliplatin/fluoropyrimidine-based adjuvant chemotherapy (CT) is non-inferior to the 6-month (6M) administration in 3-year disease-free survival (3yDFS) in high-risk (HR) stage II or stage III colon cancer (CC). Hellenic Oncology Research Group (HORG)-IDEA randomized patients between 3M and 6M of CT with FOLFOX4 or CAPOX. In total 1115 patients, 413 with HR stage II and 702 with stage III CC, were randomized. The median follow-up was 67.0 (38.3-126.0) months. Overall, 394 DFS events (202 in 3M arm and 192 in 6M arm) where recorded. The 3yDFS rate was 77.2% [95% confidence interval (CI) 72.1% to 82.3%] for 3M and 77.9% (72.6% to 82.5%) for 6M of treatment [hazard ratio (HR) 1.05 (95% CI 0.61-1.55); P = 0.647]. Eighty DFS events (3M N = 41; 6M N = 39) were observed in HR stage II patients for a 3yDFS rate of 82.7% and 83.4%, respectively (HR 1.05; 95% CI 0.68-1.63, P = 0.829). For stage III patients, 314 DFS events (3M N = 161 and 6M N = 153) were observed, for a 3yDFS rate of 72.9% for 3M versus 74.1% for 6M (HR 1.06; 95% CI 0.81-1.42, P = 0.622). For HR stage II patients receiving FOLFOX4, 3yDFS rate was 76.7% for 3M and 79.3% for 6M (HR 1.21; 95% CI 0.54-2.70). For HR stage II patients receiving CAPOX the 3yDFS rate was 85.4% for 3M and 83.8% for 6M (HR 0.99; 95% CI 0.59-1.67). For stage III patients receiving FOLFOX4, the 3yDFS rate was 71.5% for 3M and 77.3% for 6M (HR 1.18; 95% CI 0.74-1.86). For stage III patients receiving CAPOX, the 3yDFS rate was 74.5% for 3M and 74.7% for 6M (HR 0.99; 95% CI 0.70-1.44). The results of the HORG-IDEA study are in line with those of the global IDEA project, indicating that the 3yDFS is dependent on the administered adjuvant regimen and the choice and duration of regimen should be personalized. NCT01308086.