BackgroundChloroquine (CQ), the worldwide used anti-malarial drug, has recently being focused as a potential anti-cancer agent as well as a chemosensitizer when used in combination with anti-cancer drugs. It has been shown to inhibit cell growth and/or to induce cell death in various types of cancer. 5-Fluorouracil (5-FU) is the chemotherapeutic agent of first choice in colorectal cancer, but in most cases, resistance to 5-FU develops through various mechanisms. Here, we focused on the combination of CQ as a mechanism to potentiate the inhibitory effect of 5-FU on human colon cancer cells.MethodsHT-29 cells were treated with CQ and/or 5-FU, and their proliferative ability, apoptosis and autophagy induction effects, and the affection of the cell cycle were evaluated. The proliferative ability of HT-29 was analyzed by the MTS assay. Apoptosis was quantified by flow-cytometry after double-staining of the cells with AnnexinV/PI. The cell cycle was evaluated by flow-cytometry after staining of cells with PI. Autophagy was quantified by flow-cytometry and Western blot analysis. Finally, to evaluate the fate of the cells treated with CQ and/or 5-FU, the colony formation assay was performed.Results5-FU inhibited the proliferative activity of HT-29 cells, which was mostly dependent on the arrest of the cells to the G0/G1-phase but also partially on apoptosis induction, and the effect was potentiated by CQ pre-treatment. The potentiation of the inhibitory effect of 5-FU by CQ was dependent on the increase of p21Cip1 and p27Kip1 and the decrease of CDK2. Since CQ is reported to inhibit autophagy, the catabolic process necessary for cell survival under conditions of cell starvation or stress, which is induced by cancer cells as a protective mechanism against chemotherapeutic agents, we also analyzed the induction of autophagy in HT-29. HT-29 induced autophagy in response to 5-FU, and CQ inhibited this induction, a possible mechanism of the potentiation of the anti-cancer effect of 5-FU.ConclusionOur findings suggest that the combination therapy with CQ should be a novel therapeutic modality to improve efficacy of 5-FU-based chemotherapy, possibly by inhibiting autophagy-dependent resistance to chemotherapy.

Preoperative thrombocytosis is not only an independent indicator of poor CSS in CRC patients but also an independent predictor of poor DFS in patients with stage II CRC.

The present results demonstrate induction of autophagy in colon cancer cells as a protective reaction against the proapoptotic effect of SUL, and consequently, the potentiation of the proapoptotic effect by autophagy inhibition. These findings provide a premise for use of autophagy inhibitors in combination with chemotherapeutic agents for treatment of colorectal cancer.

The primary tumor location of nonmetastatic colon cancer might have different prognostic implications for the rates of recurrence after curative resection and cancer-specific mortality after recurrence.

Colorectal mixed adenoneuroendocrine carcinoma (MANEC), which acts like an aggressive tumor, is a rare clinical manifestation on which only a limited amount of literature exists. Surgical resection by regional lymphadenectomy is considered as the only curative treatment for colorectal MANEC, and adjuvant chemotherapy or radiotherapy is recommended because of its high recurrence rate. Colorectal MANEC is frequently diagnosed at an advanced stage, when it is unresectable, and chemotherapy plays a central role in its treatment. Pathological confirmation of the target lesion component is critical for regimen selection. If the lesion comprises an adenocarcinomatous component, a regimen for colorectal adenocarcinoma should be administered. For lesions comprising mainly a neuroendocrine carcinomatous component, cisplatin combined with etoposide or irinotecan has proven to be clinically appropriate. Everolimus, a mechanistic target of rapamycin pathway inhibitor, also improves survival. Sunitinib malate, another molecular targeting agent, is effective for treating neuroendocrine carcinoma; however, the evidence on its effectiveness for treating gastrointestinal neuroendocrine carcinoma is insufficient.

Background: The aim of this study was to assess whether the neutrophil to lymphocyte ratio (NLR) and other laboratory markers may predict the prognosis of advanced colorectal cancer (CRC) patients receiving palliative chemotherapy. Methods: The study population included50 patients with far advanced or recurrent unresectable CRC who received oxaliplatin-based combination chemotherapy as first-line treatment in our hospital between June 2005 and November 2010. Seven clinical variables and 7 laboratory indices before chemotherapy were evaluated retrospectively as the possible prognostic factors of overall and progression-free survival. Results: During the study period, 27 patients (54%) died of CRC. Elevated NLR (≥4.0) was observed in 15 patients (30%). By univariate analysis, elevated NLR, performance status and hypoalbuminemia were significantly associated with both poor overall and progression-free survivals. Multivariate analysis showed that elevated NLR (hazard ratio 4.39, 95% confidence interval 1.82–10.7; p = 0.0013) and thrombocytosis (hazard ratio 5.02, 95% confidence interval 1.69–13.4; p = 0.0066) were independently associated with overall survival. Conclusion: Elevated NLR is a powerful predictor of poor response to oxaliplatin-based chemotherapy in patients with unresectable CRC. The ratio is a simply accessible and inexpensive but useful biomarker in CRC patients receiving chemotherapy.

Similar to cancer cells, ECs induced autophagy in response to the pro-apoptotic agent, SUL, and the inhibition of autophagy potentiated the pro-apoptotic effect. These findings open premises for the use of autophagy inhibitors in combination with anti-angiogenic agents.

Colorectal cancer (CRC) is one of the most common cancers globally as well as in Japan and has shown a pattern of increasing incidence and mortality rates. Therefore, guidelines for CRC are considered to be crucial for establishing standard medical treatment not only in Japan but also around the world. In this article, we explain the features of the representative guidelines in Japan (Japanese Society for Cancer of the Colon and Rectum [JSCCR]), the USA (National Comprehensive Cancer Network [NCCN]) and Europe (European Society for Medical Oncology [ESMO]) and review the differences among these guidelines for CRC. We focus, in particular, on the descriptions of local treatments, including endoscopic treatment for CRC and transanal excision for lower rectal cancer; surgical treatments with lymph node dissection, including management of lower rectal cancer with lateral lymph node metastasis and laparoscopic surgery; and chemotherapy. Although the guidelines share basic principles, some details are different. Consulting the guidelines of various regions from around the world may aid in more precise and effective examination of the details and backgrounds of our own native guidelines.