The group held a conference calls on Jan. 17 and March 7 and the next call is scheduled for May 2.
Jan. 17: Dr. Svetlov received 3 PMP cell lines that Dr. Li shipped to him, PMP441, PMP457, and PMP501, and he began culturing these cells. Unlike the other two cell lines, the PMP501 cell culture showed contamination, which Dr. Svetlov attributed to bacteria. He and Dr. Li exchanged a number of emails about the contamination issue. Dr. Li mentioned that the problem may have arisen after his first postdoc left and her replacement took over her work. Since then he has also seen a contamination problem. Dr. Svetlov asked for help with how to approach the contamination problem and Dr. Li suggested using antibiotics the eliminate the bacterial contaminant. Dr. Testerman also contributed to the email discussion about how to eliminate the contaminating bacteria. Dr. Li said that he could resend the PMP501 cells and it was suggested that vancomycin be used to treat them. Dr. Svetlov has started doing dose response studies with the new PMP drug he is testing and the initial results look promising. The drug shows apoptotic activity and it gives superior results compared to mitomycin. He is also testing the new drug on colon cancer LS174 cells. Dr. Svetlov hopes to have more substantial results in a week or two. Dr. Svetlov pointed out that the PMP441 and PMP457 cells grow slowly whereas the PMP501 cells grew much faster. Dr. Merrell raised the question about whether the bacteria in the PMP501 culture could have come from the cells themselves. Dr. Testerman thought that since the contaminating bacteria grew quickly they were probably a contaminant. She also suggested that a DNA probe to amplify the 16s gene could help identify the bacterial contaminant and that result could be helpful in deciding what antibiotic to use for bacterial elimination.
Ms. Nieciecki reported that after reviewer comments were addressed, the mSystems paper was sent back to the journal yesterday. Dr. Metcalf felt that it is likely that no additional review will be needed before the paper is accepted. Ms. Nieciecki will defend her thesis in six weeks and the paper will be a chapter in her thesis.
Ms King mentioned that there was nothing new to report from Mercy. She has sent out the updated information on results from the PMP patients treated with antibiotics at Mercy just after our last call. Dr. Mc Avoy mentioned that it appeared that antibiotics appeared to be beneficial in all the cases in the report. A discussion was then held about the antibiotic results for the Mercy PMP patients.
Prior to the conference call Dr. McAvoy sent out a copy of a soon to be published paper he found on the connection between fusobacterium nucleatum and appendiceal cancer (https://www.sciencedirect.com/science/article/pii/S2950247025000015). Mr. Dahl also shared an NCI link about fusobacterium nucleatum and colon cancer (https://www.cancer.gov/news-events/cancer-currents-blog/2024/colorectal-cancer-fna-c2-bacteria). The PMP paper found higher levels of the bacteria in appendiceal cancer tissues than in healthy appendix tissues, and that the bacteria decreases CD8+ killer T cells. A lengthy discussion about the paper took place. Since the bacteria affects the immune system, it may not be the source of the cancer but only facilitate its development.
March 7: Mr. Dhal discussed the progress that has been made on the research on a new formulation of a PMP drug, TRAABA24 Nanoparticle, he has been studying with Dr. Svetlov. Mr. Dhal was a great help in writing the following minutes. A preclinical study of TRAABA24 Nanoparticle in PMP cell lines has been completed. ED50 is a metric representing the dose of a medication that produces the intended pharmacological effect in 50% of a cell line studied during a trial. The ED50 values that were determined for TRAABA24 Nanoparticle are as follows:
PMP cell lineED50Values:
MitomycinC: 17.4uM
TRAABA24: 22.7uM
Doxorubicin: 24.1uM
Doxorubicin is an antibiotic chemotherapy drug that treats many types of cancer.
HIEC-6 is a valuable cell line for modeling the gastrointestinal (GI) barrier, providing insights into normal intestinal survival and viability. It plays a crucial role in assessing the safety profile and selectivity of drugs. The results for the new formulation in HIEC-6 were observed as follows:
HIEC-6 ED50 Values:
TRAABA24: 509uM
Mitomycin C: 221uM
Doxorubicin: 162uM
These results indicate thatTRAABA24 had the most favorable therapeutic index ratio of ED50_normal / ED50_cancer of all compounds tested:
| Compound Name | Therapeutic Index ( ED50_normal / ED50_cancer ) |
| TRAABA24 | 22.4 |
| Mitomycin C | 12.7 |
| Doxorubicin | 6.72 |
TRAABA24 displayed evidence of autophagic cell death, while Mitomycin C and Doxorubicin results were indicative of apoptotic cell death. Autophagy is a process in which a cell breaks down and recycles old, damaged, or abnormal substances within its cytoplasm. The term comes from the Greek words “auto” (self) and “phagy” (eating). Apoptosis, also known as programmed cell death, results in the elimination of damaged or infected cells.
At 24 hours Mitomycin C exhibited the highest cytotoxicity in PMP cells (ED50: 17.4 µM), reducing viability more rapidly than TRAABA24 (ED50: 22.7 µM). However, by 48 hours, TRAABA24 achieved comparable cytotoxicity, suggesting a delayed but sustained effect. It is hypothesized that TRAABA24 will balance efficacy with tolerability, achieving comparable cytotoxicity over time in patients without the systemic effects of chemotherapeutic drugs.
Early in silico studies showed that TRAABA24 binds strongly to mutated GNAS (PDB REF: 6AU6), a mutation linked to PMP that drives constitutive activation of the Gs alpha subunit, leading to elevated cAMP levels responsible for some of the hallmark features of PMP.
To test this point, cAMP assays were conducted. While Mitomycin C and Doxorubicin had no impact on cAMP levels, TRAABA24 reduced activity, aligning with its predicted inhibitory effects on mutated GNAS from the in silico studies.
Full details of the study can be found at: https://binatherapeutics.com/traaba24-preclinical-results/
Dr. Metcalf reported that our paper entitled: “Cross-laboratory replication of pseudomyxoma peritonei tumor microbiome reveals reproducible microbial signatures”, was published in mSphere journal on February, 20, 2025. The article was published as an open access paper and it can be viewed free of charge. Click the word charge to get the link to the paper. Dr. Metcalf also reported that Ms. Nieciecki successfully passed he Ph.D comprehensive examination.
Dr. Metcalf brought up the discussion that the group had during the last conference call on the paper discussing the potential connection of the bacterium fusobacterium nucleatum, to PMP. She raised the possibility that if PMP tumors were detected early enough in patients, then it might be possible to carry out a 16sRNA analysis on the appendices from these patients. Such an analysis potentially would allow detecting both fusobacterium nucleatum and H. pylori from the appendix tissues. Dr. Metcalf felt that if the PMP tumors had developed further, then detection of these two bacteria might not be as easy or even possible, compared to cases where the tumors were not as old. Dr. Metcalf said that she would be willing to do the 16sRNA analysis on specimens to identify the bacteria if they could be harvested at Mercy Medical. Dr. McAvoy will contact Dr. Sardi about Dr. Metcalf’s suggestion.