Oncology Frontier: Could you discuss the role of molecular markers in choosing the appropriate treatment for individual patients with colorectal cancer?

　　结直肠癌个性化治疗的分子标志物是什么？

　　Dr Tejpar: That is certainly related to my previous answer. The sources of information that we have now to subdivide patients are very large – gene expression， microRNA， proteins and so on. We know that colon cancer is a very difficult disease. It is a disease where there are no simple principles or more frequent mutations. There is no one factor that stands out as happens in other diseases like being hormone-driven in the prostate or HER-2 breast cancer. It is the nature of the crypts themselves that adapt to survive as isolated families of cells both in the normal setting and where tumors are present and are very adaptable to the environment. There is certainly a delay of a few years compared to other diseases in coming to understand it but I think that with the tools that are available now and there is no end to the new tools that are becoming available， we will annotate the disease in sufficient detail in time to do those stratifications. It takes a lot of work， as we need to annotate thousands of samples due to the complexity of the disease. Where there are so many combinations of biology possible within the disease， we will need to easily annotate ten thousand features looking at all possible features and how they combine. There is still the unresolved issue of tumors having more than one phenotype. Are there interactions between cells within the tumor as well? We have the tools， but it is a question of getting it done and having the funding. There is already a lot of encouraging evidence from other cancers that once you are able to define groups， it is logical that there is an impact on therapy. But we need to validate all the data in order for it to be completely clinically robust and unchallengeable which is all that matters for the clinician and their patient. If it is a half-hypothesis with a lot of uncertainty and no regulatory approval， then any effort is wasted. Work needs to progress to its end， which includes clinical validation.

　　结肠癌一般是根据基因表达、microRNA、蛋白质进行分型。目前没有单一标志物可以预测这个复杂疾病的治疗，找出预测疗效的生物标志物需要大量的工作，同时还需要临床验证。

　　Oncology Frontier: The Gastrointestinal Cancer Symposium is in San Francisco this year. You have come all the way from Belgium to be here. Can you talk about the importance of this symposium to your field of focus?

　　ASCO胃癌癌症研讨会对您的研究领域的重要性如何？

　　Dr Tejpar: It is more and more important that we get the chance to meet as clinicians and researchers in the field. As I suggested in my previous responses， to crack this disease we need a very organized community. We need clinicians wanting to do those trials that will be informative trials. We need regulators and academic groups providing the samples that are required. We need pharma to be put under pressure by the whole disease community to have greater chance of achieving desired results. Then of course we need the scientists. We need functional annotated preclinical insights into pathways to understand our observations in the clinic.  I say the more the merrier in terms of these interactions. I really hope the community can come together lobbying for the stepwise key points that we need in the GI community. There are a multitude of trials going on all over the world by multiple companies working towards the same target and that just doesn’t make sense. I think， again， there is a role for the academic to try and streamline the process a little more to provide a faster， more efficient learning experience.

 　　Tejpar博士：ASCO胃癌癌症研讨会对我们的研究领域越来越重要。治疗结直肠癌需要制药商、临床医生、监管人员、科学家们的共同努力。