With football season in full swing, concussions and their long- and short-term consequences promise to be in the news. While the harmful effects of repeated concussions, especially among teens and young adults, have been well documented, any links between concussions and brain cancer are less clear. Multiple studies have endeavored to see if such links … Read more
Perhaps more than any other childhood cancer, pediatric brain tumor treatment is incredibly complex and takes a team effort to care for a patient. Doctors and researchers are working to not only improve medicines and treatment methods, they are also striving to improve quality of life and long-term side effects for young patients. “The goal … Read more
The blood-brain barrier surrounds the brain and prevents harmful toxins and bacteria in the blood stream from entering the vital organ. What evolved as a life-saving defense, however, also blocks many drugs from reaching the brain, creating a major problem in treating brain tumors. The blood-brain barrier is formed by tightly-packed cells lining the walls … Read more
Over two-thirds of patients who receive chemotherapy report experiencing a mental fog during or after treatment. This is often referred to as chemo brain.
As one of the most difficult cancers to treat, childhood brain tumors are the leading cause of cancer-related deaths in children under age 10. However, researchers are making more progress than ever before. “Over the last 10 years there has been a lot of excitement about new treatments for pediatric brain tumors,” says Peter Manley, … Read more
Brain tumors are relatively rare for people of any age, but they can occur in both children and adults. In fact, tumors of the spinal cord and brain are the second most common types of cancer in children, after leukemia. But there are some key differences between brain tumors that occur in adults and those … Read more
Until a few years ago, there were only a handful of known survivors of atypical teratoid rhabdoid tumor (AT/RT), a rare cancer that affects the brain and central nervous system. When researchers at Dana-Farber/Boston Children’s Cancer and Blood Disorders Center studied how these few survivors were treated, they found three had been given an unusual … Read more
The information used in diagnosing a brain tumor takes many forms. At Dana-Farber/Brigham and Women’s Cancer Center (DF/BWCC), patients’ brain tumor tissue undergoes a broad range of diagnostic tests: not only standard pathology exams in which tumor cells are viewed under a microscope, but also next-generation scans for mutated genes and misassembled chromosomes, as well … Read more
Researchers in Dana-Farber’s Center for Neuro-Oncology are now launching attacks on glioblastomas from a new angle – by turning the patient’s immune system against the cancer cells. Where targeted chemotherapy uses drugs to disable proteins that cancer cells need to grow, immunotherapy drugs stimulate the patient’s immune system to recognize and kill cancer cells. Traditional drugs … Read more
For many patients with brain tumors or other abnormal tissue located deep in the brain, treatment options have been limited. Last year, Jill Colter, now 50, discovered that a brain tumor resulting from Stage IV melanoma had returned. “Several years earlier, I had treatment with surgery and radiation, but the tumor came back,” Jill said. … Read more
Cognitive dysfunction is a common and frustrating side effect for many patients who undergo chemotherapy. The condition – also called “chemobrain” – can create problems with memory, attention and concentration, information processing, and mental skills used for organizing and scheduling. For many years, medical professionals were skeptical that these cognitive issues were a real side effect of … Read more
Dana-Farber Cancer Institute recently partnered with CancerConnect and Lakshmi Nayak, MD, to answer questions about brain cancer. Nayak is a neuro-oncologist in the Center for Neuro-Oncology at Dana-Farber/Brigham and Women’s Cancer Center and an instructor in neurology at Harvard Medical School. Q: There seems to be some progress concerning treatment of brain tumors, especially immunotherapy. … Read more
During a child’s cancer therapy and recovery process, insomnia can often be viewed as only a side effect in the scope of treatment-related symptoms. However, there are many physical and psychological implications that develop when a child does not sleep well, says Eric Zhou, PhD, a clinical psychology fellow in Dana-Farber’s David B. Perini, Jr. … Read more
Highly malignant brain tumors called glioblastomas are the most common primary cancer of the brain; about 11,000 cases are diagnosed every year in the United States. Patrick Y. Wen, MD (Director) and David Reardon, MD, (Medical Director) of the Center for Neuro-Oncology at Dana-Farber/Brigham and Women’s Cancer Center describe the efforts to improve care for … Read more
By Eric Schuller If you recently learned you have cancer, donating a sample of your cancer tissue to science is probably the last thing on your mind. But it’s a topic that you might discuss with someone on your health care team, because cancer researchers often rely on donated tissue samples to help them better … Read more
Musician Sheryl Crow announced on June 5 that she has a benign brain tumor known as a meningioma. Below, doctors from Dana-Farber’s Center for Neuro-Oncology describe this condition. The singer-songwriter, a breast cancer survivor, visited Dana-Farber in 2006. Meningiomas are tumors on the surface of the brain, spinal cord, and fluid spaces. They are the … Read more
More than 600,000 people in the United States are living with a primary brain tumor — one that begins and stays in the brain — and over 60,000 adults and children will be diagnosed with a brain tumor this year. In recognition of May as Brain Tumor Awareness Month, we asked David Reardon, MD, clinical … Read more
Runners call it Heartbreak Hill, but for Michelle O’Brien the long, rising stretch of pavement that crosses the 20-mile point of the Boston Marathon® route represents the top of the mountain. Just over three years after being diagnosed in back-to-back months with two unrelated cancers — invasive breast cancer in December 2020, and then stage … Read more
发布日期：2023年5月16日 医学审校：Robert J. Mayer博士（Robert J. Mayer, MD） 细胞周期包含一系列步骤，包括：活细胞生长、复制其DNA，并分裂成两个相同的子代细胞，每个子细胞获得母本的一份拷贝。当每个子细胞被封存在自身的膜内时，细胞周期完成，为开启新的细胞周期做好准备。 细胞周期以一种精确运转的方式展开，确保细胞将DNA的精准拷贝遗传给其子代细胞。在分裂前的DNA复制或DNA迁移到新形成的细胞的过程中，如果出现任何错误，那么细胞的遗传程序都会出错，从而导致癌症或其他疾病的产生。 细胞周期的分期（Stage） 在含有细胞核的细胞内，细胞周期有5个分期： G0期：细胞尚未分裂，在体内中正常运作 G1期（gap 1）：细胞生长 S期 (synthesis 合成) ：细胞复制其DNA G2期 (gap 2) ：细胞准备分裂 M期 (mitosis 有丝分裂) ：细胞核（nucleus）和细胞质（cytoplasm）分裂，形成两个子代细胞 人体细胞用90%的时间完成前三个分期， 统称分裂间期（interphase）。 细胞周期的持续时间因细胞类型而异。大部分人体细胞在24小时左右完成周期。快速生长的细胞（如肠道内壁细胞）或在9-10小时内完成分期，而肝细胞的分期则超过一年，神经细胞的分期则需更多年完成。 细胞分期和癌症 在细胞周期任何阶段出现的失误或错误——特别是在DNA复制或DNA分配给子细胞的过程中出错，都会驱使细胞向产生癌变的方向演化。 细胞周期含有若干检查点，其作用类似流水线上的阀门，让细胞“扫描”问题并采取必要的修复措施。细胞借此机会来确认自身生长到应有的大小、正确地复制了自身的DNA、准确地排列了用于分裂的染色体。细胞或修复错误，但如果严重的话，细胞也会通过自毁的方式避免将自身的错误传给后代。 若干蛋白质控制检查点，其中最重要的检查点之一是p53，它在细胞周期中主要在G1检查点上作用。当一个细胞的DNA受损时，一个蛋白质激活p53，p53终止细胞周期并下达修复的指令，如果出现不可修复的损伤，p53会引起细胞消亡。p53对健康细胞的延续而言至关重要，它也被视为基因组的护卫。 如果p53消失、发生故障或者比活性低于正常水平，它或许会让携带受损DNA的一个细胞进入细胞周期的下一阶段，增加DNA拼写错误且遗传给子细胞的几率。这种错误在多个细胞周期中不断累积，就会向癌症迈进一步。p53 是人类癌症中最常见的突变基因。 化疗如何影响细胞周期？ 在细胞周期的不同阶段，不同类型的化疗（chemotherapy）药物会对癌细胞发起攻击。 有些化疗药物对细胞周期的一个特定阶段作用。例如，抗代谢药（antimetabolite）和叶酸拮抗剂（antifol）就以S期为靶点，干扰DNA分子的构建。博来霉素（bleomycin）和依托泊苷（etoposide）和其它药物则以G2期为靶点，使DNA断裂；长春花生物碱类（vinca alkaloids）以M期为靶点，防止染色体在细胞分裂的过程中正确排列。 还有一些药物可作用于分裂中的细胞，无论细胞周期。这些药物包括：烷化剂（alkylating agents）——与DNA结合并阻止DNA复制；嵌入剂（intercalators）——起作用是扭曲DNA双螺旋的正常形状和结构。 第三类药物对癌细胞作用显著，无论癌细胞处在细胞周期的何种阶段。这些药物包括：皮质类固醇（corticosteroids）和激素拮抗剂（hormone antagonists），其作用机制是与细胞受体结合，防止细胞接收到生长信号。 放疗如何影响细胞周期？ 辐射会杀死处于积极分裂中的细胞，即不处于G0期的细胞。因为癌细胞无序生长，与正常细胞相比，它们或需要更多的时间完成分裂，所以癌细胞特别容易受到放疗的影响。 靶向治疗如何干预细胞周期？ 靶向疗法（targeted therapies）是一组抑制与癌症有关的特异性细胞蛋白质的药物。靶向疗法的药物有一部分作为标准治疗用药，有一些尚处于临床试验中，其核心聚焦于在细胞周期中起到关键作用的蛋白质。 以CDK4和CDK6蛋白质为例，这两种蛋白质在细胞周期的一个重要节点扮演着保护的作用，即细胞从G0期和G1期向S期过渡。在有些癌症病种中，CDK4和CDK6蛋白质的异常会使细胞分裂进入高速运转的状态。以CDK4/6抑制剂（CDK4/6 inhibitors）为代表的的药物干扰这些蛋白质，有助于阻止细胞周期的展开。在某些情况下，癌细胞不仅停止分裂，还会丧失所有用于循环和生长的能力，使得肿瘤缩小。CDK4/6抑制剂在治疗晚期雌激素受体阳性和HER2-阴性乳腺癌（advanced estrogen receptor-positive and HER2-negative breast … Read more
Ruth Nelson struggled with her new breast cancer diagnosis mentally and physically. On treatment, her cardiac health faltered, her blood pressure spiked, and she experienced an unexplained episode in which she briefly lost her speech. And on top of that, she felt as if she were “a problem to be managed” by her friends and … Read more