Week 5—Joyce

This week has no clinical surgeries but some interesting translational work done: We (Dr. Lipkin and me) analyzed the clinical colorectal cancer samples by histological staining and gene profiling, (of course with the IRB approvals). After several years developing and studying different animal models for colorectal cancers (CRC), I was very curious to see how the real human samples look like and how similar the human samples and mouse models are. We accessed the patient database and descriptions including cancer grade / stage and gene markers which are very helpful information for our research projects. The H+E (hematoxylin stains nuclear and eosin stains cytoplasm) staining is a classic and very helpful histology staining for primary pathology screening. The row cancer stages could be roughly identified by HE staining: adenoma limited in intestinal epithelium (stage 1/2); adenocarinoma invasive into submucomsa and lamina propria (LP) (stage 2/3); adenocarcinoma invasive into muscular layers (stage 2/3); distant location metastasis (stage 4). Other information like lymph node negative or positive cancer cells is also needed for the more accurate diagnosis. Several cases are interesting to me. For examples, the CRC invaded into colon well and metastatic to the connect tissues, adipose tissues and abdomen lumen, while the lymph node was negative. And we found the lines I developed generating mouse liver metastasis are from high invasive CRC but no distant metastasis so we define they are stage 2/3 CRC. Additionally, we check the gene profiling for some markers like MLH1, APC, KRAS and P53, combined with the pathological slides for better analysis.
Research project works smoothly. The primers for KRAS and BRAF hotspot regions work well and the PCR DNA are extracted from four primary culture CRC cells and the sequencing results should be back by next week. We also work on some pilot pharmaceutically screenings on these CRC cells and identify some components / drugs are sensitive. We follow to repeat the metastatic mouse models and also prepare to infect the cells with fluorescent – luciferase virus then will dynamically track the metastasizing process in IVIS system. In the other hand, we are interested in genome / exon sequencing on the two aggressive lines for candidate genes of liver metastasis.