网上浏览的：新的研究提供了了解常见癌症的突破

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Researchers from the University of Sheffield have discovered valuable insight into how people develop B-cell lymphoma, one of the most common cancers in the UK./ F4 J$ J) s% O8 \% A5 G
The team, from the University’s Institute for Cancer Studies and funded by Leukaemia and Lymphoma Research, Biotechnology and Biological Sciences Research Council (BBSRC) and Yorkshire Cancer Research, found that a mechanism different to that previously thought to be the cause of lymphoma may be responsible for the development of the disease.
- q) W0 {  b  ~. k6 ULymphoma is a type of cancer that affects the blood, originating in the lymph glands. B-cells are the immune cells in the human body that are responsible for producing antibodies to fight infections and provide long-term immunity. B-cell lymphomas include both Hodgkin’s lymphomas and most non-Hodgkin’s lymphomas.
$ E7 S- l* [  e. T4 {3 zPrior to this research, the main theory to explain the origins of lymphoma was the malfunction of a mechanism (somatic hypermutation) used by B-cells to modify the genes coding for antibodies. This mechanism is required to produce highly specific antibodies, but it also accidentally alters other genes, leading to lymphoma." _% n/ R& w* F" Z  Y  G
However, the team from the University knew that this theory only accounted for affecting a handful of genes, and the model could only explain certain types of lymphoma.3 t; P3 U' k& S+ W) P
Led by Dr Thierry Nouspikel, the researchers discovered another mechanism, which potentially affects many more genes and can account for a wider palette of lymphomas. The research found that B-cells actually do not repair the bulk of their DNA and only take care of the few genes they are using. When the B-cells are inert in the blood flow, this is not a problem. However, when they receive a stimulation (e.g. an infection) they start to proliferate and then produce antibodies.
6 {) L* ^: q- H/ P+ O) I) S5 VTo proliferate they must replicate their DNA, and replication of damaged DNA results in the introduction of mutations, the accumulation of which can lead to lymphoma. Dr Nouspikel’s team have designed a novel method to specifically detect such mutations, and have proved that they do occur in genes that have been implicated in lymphoma.9 g3 I" E& ~8 a( n! n$ }0 ~0 m
The researchers demonstrated that B-cells are deficient in one of the main DNA repair pathways, known as Nucleotide Excision Repair. This pathway repairs a lot of different DNA lesions, including UV-induced damage and chemical adducts (e.g. from air pollution and cigarette smoke). Their model therefore explains why strong UV exposure (e.g. unprotected sun bathing) is the number one environmental risk factor for lymphoma and also supports the evidence that exposure to air pollution and smoking are also risk factors.9 c7 |+ @9 r1 \5 o/ z9 Q! M& N
Dr Nouspikel said: “Lymphoma is one of the ten most frequent cancers in adults in the UK, and the third among children. If we want to come up with efficient strategies for prevention and therapy, it is crucial to understand what causes it. The novel mechanism we have discovered potentially accounts for the development of many different types of lymphoma. It may also explain why strong exposure to sunlight is the main environmental risk factor for this cancer.”6 X, L3 I) Z/ {

1 ]9 r; ?# J% N1 s2 _通过软件直译/ ]1 [5 E, ?) v3 w$ G: \
来自谢菲尔德大学的研究人员已经发现人们如何开发B细胞淋巴瘤，在英国最常见的癌症之一有价值的见解。
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3 _1 `: o, C" ^% S8 L$ L从大学的癌症研究和资助的白血病和淋巴瘤的研究，生物技术和生物科学研究理事会（BBSRC）和约克郡癌症研究，发现一种机制不同，以前认为是淋巴瘤的原因可能是负责研究所的研究人员，对于这种疾病的发展。
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淋巴瘤是一种癌症的类型，影响血液，淋巴腺始发。 B细胞是人体的可用于制造抗体抵抗感染和提供长期免疫力负责免疫细胞。 B细胞淋巴瘤包括霍奇金淋巴瘤和大多数非霍奇金淋巴瘤。
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在此之前的研究，主要的理论来解释淋巴瘤的起源是由B细胞用于修改为抗体编码的基因机制（体细胞超突变）故障。这个机制是需要高度特异性抗体产生，但它也无意改变其他基因，导致淋巴瘤。
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; J: ]/ Y+ U1 {; A+ A  q7 L9 D然而，从大学队知道，这个理论只影响极少数的基因占和模型只能解释某些类型的淋巴瘤。
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" B) O& S9 h+ ^/ k  }- m蒂埃里Nouspikel博士的带领下，研究人员发现了另一种机制，这可能影响到许多更多的基因，可占了淋巴瘤更广泛的调色板。研究发现，B细胞其实不修复他们的DNA散装和只照顾他们使用的是几个基因的照顾。当B细胞是在血液流动的惰性，这不是一个问题。然而，当他们收到刺激（如感染），他们开始增殖，然后产生抗体。
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增殖，他们必须复制其DNA，并在突变介绍，积累可导致淋巴瘤受损的DNA复制的结果。 Nouspikel博士的研究小组设计了一种新颖的方法，专门检测这种突变，并已证明，他们确实发生在已在淋巴瘤牵连的基因。 * U- u: u5 J( H& d3 E3 }( J

4 t0 |) E0 I- @, m研究人员表明，B细胞中的DNA修复为主要核苷酸切除修复已知的途径，一个不足之处。这种途径的不同的DNA修复病变很多，包括紫外线损伤和化学加合物（空气污染和香烟烟雾中）。因此，他们的模型解释了为什么强烈的紫外线照射（如无保护晒太阳）是头号淋巴瘤的环境风险因素，同时还支持证据表明，暴露在空气污染和吸烟也是危险因素。 ; B( W0 e0 g1 n+ r4 D) A

' M% H% r2 f! C3 Z. y" \2 sNouspikel博士说：“淋巴瘤是一种最常见的十大在英国成人癌症，儿童和第三。如果我们要拿出有效的预防和治疗策略时，关键的是要了解什么原因造成的。新颖的机制，我们已经发现可能占了许多不同类型的淋巴瘤的发展。这也可以解释为什么在阳光强烈照射的主要是这种癌症的环境风险因素。“ " j9 q$ j+ V7 k9 @+ f* Y+ U
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