SIRT1 inhibitors mitigate radiation-induced GI syndrome by enhancing intestinal-stem-cell survival.

High-dose radiation exposure induces gastrointestinal (GI) stem cell death, resulting in denudation of the intestinal mucosa and lethality from GI syndrome, for which there is currently no effective therapy. Studying an intestinal organoid-based functional model, we found that Sirtuin1(SIRT1) inhibition through genetic knockout or pharmacologic inhibition significantly improved mouse and human intestinal organoid survival after irradiation. Remarkably, mice administered with two doseages of SIRT1 inhibitors at 24 and 96 h after lethal irradiation promoted Lgr5+ intestinal stem cell and crypt recovery, with improved mouse survival (88.89% of mice in the treated group vs. 0% of mice in the control group). Moreover, our data revealed that SIRT1 inhibition increased p53 acetylation, resulting in the stabilization of p53 and likely contributing to the survival of intestinal epithelial cells post-radiation. These results demonstrate that SIRT1 inhibitors are effective clinical countermeasures to mitigate GI toxicity from potentially lethal radiation exposure.

Fusobacterium nucleatum promotes chemoresistance to 5-fluorouracil by upregulation of BIRC3 expression in colorectal cancer.

BACKGROUND: Emerging evidence suggests a potential relationship between gut microbiota and the host response to chemotherapeutic drugs including 5-fluorouracil (5-Fu). Fusobacterium nucleatum (Fn) has been linked to the initiation and progression of colorectal cancer (CRC). Unfortunately, little was known about the relationship between Fn infection and chemotherapeutic efficacy. Here, we investigate the potential relationship between Fn infection and chemotherapeutic efficacy of 5-Fu in CRC. METHODS: Differentially expressed genes of CRC cell lines induced by Fn infection were analyzed based on a whole genome microarray analysis Then, we explored the relationship between upregulation of BIRC3 induced by Fn infection and chemoresistance to 5-Fu in vitro and in vivo. Furthermore, we dissected the mechanisms involved in Fn-induced BIRC3 expression. Finally, we investigated the clinical relevance of Fn infection, BIRC3 protein expression and chemoresistance to 5-Fu treatment in CRC patients. RESULTS: BIRC3 was the most upregulated gene induced by Fn infection via the TLR4/NF-κB pathway in CRC cells; Fn infection reduced the chemosensitivity of CRC cells to 5-Fu through upregulation of BIRC3 in vitro and in vivo. High Fn abundance correlated with chemoresistance in advanced CRC patients who received standard 5-Fu-based adjuvant chemotherapy after radical surgery. CONCLUSIONS: Our evidence suggests that Fn and BIRC3 may serve as promising therapeutic targets for reducing chemoresistance to 5-Fu treatment in advanced CRC.

HER2 as a potential biomarker guiding adjuvant chemotherapy in stage II colorectal cancer.

BACKGROUND: HER2 is a well-established therapeutic target in breast and gastric cancers, while the role of HER2 in colorectal cancer is unclear, and no studies have explored the impact of HER2 on the outcome of stage II colorectal cancer patients treated with 5-fluorouracial based adjuvant chemotherapy. METHODS: We analyzed HER2 mRNA expression of 206 patients in GSE39582 dataset and explored the impact of HER2 expression on benefit from adjuvant chemotherapy for stage II colon cancer patients. We further validated the finding by retrospectively analyzing HER2 detection of immunohistochemistry in a cohort of 282 patients in Fudan University Shanghai Cancer Center (FUSCC). RESULTS: In GSE39582 dataset, chemo-treated HER2-high patients had a better overall survival (OS) and relapse-free survival (RFS) versus chemo-naïve HER2-high patients (5-year OS: 100% vs 69.5%, 5-year RFS: 100% and vs 64%, P = 0.027 and 0.025, respectively). On the contrary, chemo-treated HER2-low patients had a worse RFS compared with chemo-naïve HER2-low patients (5-year RFS: 65.6% vs 82.1%, P = 0.022). In FUSCC cohort, chemo-treated HER2-positive patients exhibited better OS vs chemo-naïve HER2-positive patients (5-year OS: 100% vs 73.8%, P < 0.001), and showed marginal evidence of a lower probability of recurrence (5-year RFS: 74.4% vs 58.7%, P = 0.072). After stratifying by mismatch repair (MMR) status, the results only kept consistency in patients with pMMR status. CONCLUSIONS: HER2-positve patients with stage II colorectal cancer can benefit from 5-fluorouracial based adjuvant chemotherapy, especially for patients with pMMR status.

A study of peritoneal metastatic xenograft model of colorectal cancer in the treatment of hyperthermic intraperitoneal chemotherapy with Raltitrexed.

Peritoneal metastasis of colorectal cancer is one of the most incident and fateful diseases among relapse cases. It shows a certain resistance to systemic chemotherapy. The perfusion system in clinic is complex and hard to be used in fundamental researches. This study aims at evaluating the effect of an improved hyperthermic intraperitoneal chemotherapy with Raltitrexed used in tumor-bearing mice with peritoneal metastatic colorectal carcinoma. The results showed that no severe adverse effect was observed. All control animals developed extensive peritoneal and mesenteric metastatic nodes. Tumor sites in the treatment groups were reduced significantly. The administration dose of Raltitrexed influenced concentration in systemic blood and peritoneal tissues. Temperature promoted the intracellular absorption of Raltitrexed significantly. Our findings reveal that hyperthermic intraperitoneal chemotherapy is an efficient therapy in treating peritoneal metastatic carcinoma in nude mice. It can effectively reduce the extension of carcinoma cells from macro and micro examination. The combination of hyperthermia and Raltitrexed resulted in an improved therapeutic effect on animal models.

Manganese Oxide-Coated Carbon Nanotubes As Dual-Modality Lymph Mapping Agents for Photothermal Therapy of Tumor Metastasis.

Lymph node (LN) status is a major indicator of stage and survival of lung cancer patients. LN dissection is a primary option for lung cancer LN metastasis; however, this strategy elicits adverse effects and great trauma. Therefore, developing a minimally invasive technique to cure LN metastasis of lung cancer is desired. In this study, multiwalled carbon nanotubes (MWNTs) coated with manganese oxide (MnO) and polyethylene glycol (PEG) (namely MWNTs-MnO-PEG) was employed as a lymphatic theranostic agent to diagnose and treat metastatic LNs. After single local injection and lymph drainage were performed, regional LNs were clearly mapped by T1-weighted magnetic resonance (MR) of MnO and dark dye imaging of MWNTs. Meanwhile, metastatic LNs could be simultaneously ablated by near-infrared (NIR) irradiation under the guidance of dual-modality mapping. The excellent result was obtained in mice bearing LNs metastasis models, showing that MWNTs-MnO-PEG as a multifunctional theranostic agent was competent for dual-modality mapping guided photothermal therapy of metastatic LNs.

A distinct metabolic signature of human colorectal cancer with prognostic potential.

PURPOSE: Metabolic phenotyping has provided important biomarker findings, which, unfortunately, are rarely replicated across different sample sets due to the variations from different analytical and clinical protocols used in the studies. To date, very few metabolic hallmarks in a given cancer type have been confirmed and validated by use of a metabolomic approach and other clinical modalities. Here, we report a metabolomics study to identify potential metabolite biomarkers of colorectal cancer with potential theranostic value. EXPERIMENTAL DESIGN: Gas chromatography-time-of-flight mass spectrometry (GC-TOFMS)-based metabolomics was used to analyze 376 surgical specimens, which were collected from four independent cohorts of patients with colorectal cancer at three hospitals located in China and City of Hope Comprehensive Cancer Center in the United States. Differential metabolites were identified and evaluated as potential prognostic markers. A targeted transcriptomic analysis of 29 colorectal cancer and 27 adjacent nontumor tissues was applied to analyze the gene expression levels for key enzymes associated with these shared metabolites. RESULTS: A panel of 15 significantly altered metabolites was identified, which demonstrates the ability to predict the rate of recurrence and survival for patients after surgery and chemotherapy. The targeted transcriptomic analysis suggests that the differential expression of these metabolites is due to robust metabolic adaptations in cancer cells to increased oxidative stress as well as demand for energy, and macromolecular substrates for cell growth and proliferation. CONCLUSIONS: These patients with colorectal cancer, despite their varied genetic background, mutations, pathologic stages, and geographic locations, shared a metabolic signature that is of great prognostic and therapeutic potential.

The impact of nutritional status, nutritional risk, and nutritional treatment on clinical outcome of 2248 hospitalized cancer patients: a multi-center, prospective cohort study in Chinese teaching hospitals.

To better understand the impact of undernutrition, nutritional risk, and nutritional treatment on the clinical outcomes of hospitalized cancer patients in China, the authors conducted a multicenter, cross-sectional study with 2248 cancer patients from 20 hospitals from January to June 2010. The authors defined 19.7% and 26.8% patients as undernourished at baseline and reassessment, respectively. Patients with gastrointestinal malignancies had a higher rate of undernutrition than other patients. The nutritional risk rate was 24.6% and 40.2% at baseline and reassessment, respectively. For patients with nutritional risk, the relative risk (RR) of adverse events (AEs) significantly increased with and without nutritional treatment. In comparison with the nonnutritional treatment subgroup, patients who received enteral nutrition (EN) or total parenteral nutrition (TPN) significantly reduced the RR of AE development. The RR of AEs for EN and TPN were 0.08 (95% CI: 0.01-0.62) and 0.56 (95% CI: 0.33-0.96), respectively. Separated nutrient infusion increased the risk of AEs. The authors concluded that undernutrition and nutritional risk are general problems that impact the outcomes of hospitalized cancer patients in China. Higher NRS2002 scores are related to AE risk but not weight loss. In nutritional treatment, EN and TPN can significantly reduce the risk of AEs.