- A new study by researchers at Washington University in St. Louis challenged an established view of sugar as a cancer driver because of the cancer cells’ high glucose uptake.. The study demonstrated that cancer cells don’t use all the energy from glucose but discard most of it as waste. Until now, the rate of glucose consumption by cancer cells was used in cancer diagnosis and staging. Also, avoiding access to dietary sugar has been viewed as one of the anti-cancer strategies. The new findings don’t support the role of glucose metabolism as a good therapeutic target in cancer. The study was published in Molecular Cell.
- An international group of researchers, funded by Cancer Research UK, have developed a technique called spatial transcriptomics, which allows non-invasive mapping of tumors at a very high-resolution depth. The researchers have created a detailed three-dimensional prostate map, including both healthy and cancerous cell areas. The study also discovered that individual prostate tumors have multiple genetic variations and revealed that healthy tissue in a prostate already had genetic characteristics associated with cancer. The new technique will help study the characteristics and development of cancer on a cellular level. The technique and the finding of the study will have a significant impact on cancer diagnosis and treatment. The study was published in Nature.
- Researchers at the Georgia Institute of Technology developed a revolutionary detection method that shows how cancers metastasize and what stage they are. They created a new type of chip called the Cluster-Well, which can capture circulating tumor cell (CTC) clusters in blood, which are the vehicles of tumor spread. According to the Principal Investigator on the study, this new technology allows circulating tumor cell clusters “virtually in any cancer to be accessed with precision and practicality that has not been possible before.” The study was published in Nature Communications.
- A researcher at the University of Alabama at Birmingham School of Public Health conducted a retrospective study to evaluate the long-term relationship between cancer and Alzheimer’s Disease. The findings supported the pattern already established by the prior research into a short term relationship, that of the inverse relationship between the two conditions: “…dementia patients with cancer history demonstrated better cognition at dementia diagnosis and declined slower than dementia patients without cancer history”. The study was published in Journal of Alzheimer’s Disease.
- Researchers at the University of Southern California have found that exposure to “forever chemicals,” also known as PFAS, which are chemicals used in nonstick cookware and certain types of makeup, is associated with elevated liver cancer risk. The study was published in JHEP Reports.
Author Archives: Marina
High Tumor mRNA Levels Predict Poor Survival, Aging Drives Melanoma Metastasis and More
- Researchers at The University of Texas MD Anderson Cancer Center have developed a method to quantify tumor-specific total mRNA levels from patient tumor samples. The researchers used this method on tumors from more than 6,500 patients across 15 cancer types and found that higher mRNA levels in cancer cells were correlated with an increased risk of disease progression and poor survival. The study was published in Nature Biotechnology.
- The researchers at Johns Hopkins University investigated age-related mechanisms in melanoma metastasizing. While age-related changes suppress the growth of melanoma cells in primary tumors, this new study established aging as the factor that increased the spread of cancer cells to distant organs. This multicenter study was published in Nature.
- Although cancer cells can have thousands of mutations in their DNA, only some drive cancer progression. Scientists from MIT created a computer model that can quickly scan the genome of cancer cells and identify mutations that occur most frequently and thus potentially are responsible for driving tumor growth. The study was published in Nature Biotechnology.
- A researcher from the University of Texas synthesized a new molecule (ERX-41) that had proved, in in-vitro and animal experiments, to be effective against a broad spectrum of hard-to-treat cancers, including triple-negative breast cancer, pancreatic and ovarian cancers, and glioblastoma. The study was published in Nature Cancer.
- Cancer vaccines are on the rise as a cancer treatment modality. They work by inducing an immune response, but tumors often resist this response via an immune escape mechanism. A group of researchers from Dana-Farber Cancer Institute, Harvard Medical School, and other institutions created a new cancer vaccine targeting this mechanism and increasing immune antibody levels. The vaccine was studied on animals, and human trials are expected to come next. The study was published in Nature.
“By-product” Search Results in Systematic Review Searches
Systematic Review (SR) searching adopts both systematic and comprehensive approaches with the goal of retrieving, ideally, all the literature relevant to the focused question at the base of your Systematic Review. Typically, an expert searcher, such as an information professional, uses a combination of keywords qualified with field tags (e.g. [tiab] field tag in PubMed related to title and abstract fields of PubMed records) and subject headings (e.g. MeSH in PubMed and EmTree in Embase) for SR searching.
When selecting the terms for an SR, it is best to focus strictly on the terms directly related to the subject or clinical question being addressed. Occasionally it can be appropriate to expand the search to a slightly broader focus to retrieve literature where the exact subject matter may be discussed within the context of other subjects within a broader question.
An example of this expanded search: If the SR is focused on breast cancer surgery, a broader focus would be to look at any/all cancer surgeries wherein breast cancer specific surgery may be discussed.
All search approaches, whether broad or narrow, must be reflected in transparent and reproducible documented search strategies. It is important to remember that there is no “perfect” comprehensive search strategy that will only retrieve relevant citations. It is to be expected that any search, especially a comprehensive SR search, will retrieve many more citations than are actually relevant to the question being asked. Part of the SR process is excluding these irrelevant citations through multiple steps, explained in PRISMA.
However, there is another category besides relevant and irrelevant results, that is typically retrieved – these citations are related to aspects of your topic you did not consider when asking your clinical question and devising your search strategies. These “by-products” might appear important enough that they should be included in your review, but this will be deterring from your original question.
Example: Your SR is on cancer patients’ attitude to health. You devise a comprehensive search strategy and include relevant search terms. As you begin screening the retrieved citations you realize that many of the articles actually focus on health education as it relates to attitudes. You may want to simply add health education as an additional aspect of your SR since it appears to be a valuable aspect of cancer patients’ health attitudes.
The issue with this approach is that unless you backtrack and revise your clinical question and search strategies (and thus essentially starting over from the beginning), your results and conclusions would deviate from the actual question that was proposed initially. If health education was not addressed in your original clinical question and reflected in your search strategies, it would be improper to include it in the final SR as there is likely an entire body of literature that was missed and thus any systematic conclusions could not be made regarding it.
Instead, these “by-product” citations (health education articles that came up in search results for health attitudes) should be treated as irrelevant to the systematic review you are conducting. A potential solution could be mentioning in the discussion section that from this review it was discovered that education is strongly tied to cancer patients’ attitudes toward their disease and their health and that it would be worthwhile to conduct a future review looking at how education can impact these views.
Takeaway: Try not to include “by-product” topics in your final review and analysis.