Tagged: summary

CDR3s and Renalase-1 Correlate with Increased Melanoma Survival 

Our group has demonstrated that chemical complementarity between tumor resident, T-cell receptor, complementarity-determining region 3 (CDR3s), and MAGEA3/6 correlates with increased survival in patients with melanoma.”

In this study, Saif Zaman, Fred S. Gorelick, Andrea Chrobrutskiy, Boris I. Chobrutskiy, Gary V. Desir, and George Blanck from Yale School of MedicineVeteran’s Administration Healthcare SystemOregon Health and Science University HospitalMorsani College of Medicine, and the H. Lee Moffitt Cancer Center and Research Institute, investigated the chemical complementarity between melanoma-resident T-cell receptor (TCR) complementarity-determining region 3 (CDR3) amino acid sequences (AAs) and the renalase-1 protein. On August 5, 2024, their research paper was published in Oncotarget‘s Volume 15, entitled, “Chemical complementarity of tumor resident, T-cell receptor CDR3s and renalase-1 correlates with increased melanoma survival.”

The Study

The researchers investigated the potential of the RP220 peptide as an antigenic target for T cells by assessing the electrostatic and hydrophobic complementarity between T-cell receptor (TCR) CDR3s and the RP220 peptide of the renalase (RNLS) protein. They found that higher complementarity scores were linked to significantly improved survival probabilities, with hydrophobic forces further refining these distinctions. The associations varied depending on the dataset and method used.

The study also explored correlations between TCR CDR3-RNLS amino acid alignments and immune gene expression. Several immune signature genes, such as CD86, TIGIT, CIITA, and CD4, were significantly associated with better overall survival when showing higher complementarity scores.

Researchers also examined how RNLS expression levels affected these correlations. They found that higher RNLS mRNA expression was associated with worse survival, while lower RNLS expression combined with high complementarity scores predicted better outcomes. This trend held for both the full-length RNLS protein and the RP220 peptide.

The study revealed that specific regions of the RNLS protein, including the RP220 peptide, had higher complementarity with TCR CDR3s, suggesting they may serve as potential antigenic targets.

Discussion

The researchers explored the potential of the RNLS protein as a tumor antigen by examining the chemical complementarity between melanoma tumor-resident T-cell receptor (TCR) CDR3s and the amino acid (AA) sequence of RNLS. They found that increasing complementarity correlated with improved overall survival (OS) outcomes, supporting previous in vitro and in vivo data. This suggests that RNLS could be recognized by TCRs, triggering immune responses against melanoma.

Gene expression analyses revealed that as complementarity scores between TCRs and RNLS AAs increased, so did the expression of T-cell activation-associated genes, indicating enhanced T-cell activity and anti-tumor immune responses. The association between TCR complementarity and OS probabilities was more pronounced in cases with low RNLS expression levels, suggesting that high complementarity may be particularly beneficial in tumors with reduced RNLS-mediated immune inhibition.

These findings suggest that RNLS could serve as an antigen for TCRs in melanoma, supporting further exploration of its potential as a target for immunotherapy and vaccine design.

In conclusion, this research suggests that RNLS could potentially serve as an antigen for T-cell receptors (TCRs) in melanoma. The correlation between TCR complementarity to RNLS and improved overall survival supports the idea that T-cell responses targeting RNLS may play a role in antitumor immunity. These findings highlight the potential of RNLS as a valuable target for immunotherapy and vaccine development for melanoma treatment. 

Further research in this area is warranted.

Click here to read the full research paper in Oncotarget.

Oncotarget is an open-access, peer-reviewed journal that has published primarily oncology-focused research papers since 2010. These papers are available to readers (at no cost and free of subscription barriers) in a continuous publishing format at Oncotarget.com

Oncotarget is indexed and archived by PubMed/Medline, PubMed Central, Scopus, EMBASE, META (Chan Zuckerberg Initiative) (2018-2022), and Dimensions (Digital Science).

Click here to subscribe to Oncotarget publication updates.

For media inquiries, please contact media@impactjournals.com.

Harnessing the Power of Nanobodies: Inhibiting Metastasis of 4T1-12B Breast Tumor Cells

In this study, researchers show that treatment of 4T1-12B mouse breast cancer cells with this nanobody inhibits V-ATPase-dependent acidification of the media and invasion of these cells in vitro.

Researchers recently developed a nanobody directed against an extracellular epitope of the mouse V-ATPase c subunit. Zhen Li, Mohammed A. Alshagawi, Rebecca A. Oot, Mariam K. Alamoudi, Kevin Su, Wenhui Li, Michael P. Collins, Stephan Wilkens, and Michael Forgac from Tufts University School of MedicineTufts UniversityDana Farber Cancer Institute, Harvard Medical SchoolUniversity of Minnesota School of MedicinePrince Sattam Bin Abdulaziz UniversityKorro BioSUNY Upstate Medical University; and Foghorn Therapeutics, suggest that plasma membrane V-ATPases represent a novel therapeutic target to limit breast cancer metastasis. The vacuolar H+-ATPase (V-ATPase) is an ATP-dependent proton pump that functions to control the pH of intracellular compartments as well as to transport protons across the plasma membrane of various cell types, including cancer cells.

On August 14, 2024, their research paper was published in Oncotarget’s Volume 15, entitled, A nanobody against the V-ATPase c subunit inhibits metastasis of 4T1-12B breast tumor cells to lung in mice.”

The Research

Breast cancer is one of the most diagnosed cancers, accounting for almost one-third (30%) of all new diagnoses in women in 2022. At the time of diagnosis, 20–30% of patients with early-stage breast cancer will go on to develop metastatic breast cancer. 6–10% of all patients with breast cancer have stage IV disease at time of diagnosis. It has been shown that V-ATPase plays an important role in promoting the invasiveness of many cancer cell types, including breast cancer cells. 

This study demonstrated that inhibiting cell surface V-ATPases can effectively block tumor cell invasion. The findings indicate that anti-V-ATPase antibodies targeting an extracellular region of the V-ATPase can suppress activity on the surface of cancer cells, as well as inhibit both in vitro invasion and in vivo metastasis in a mouse model. This represents a promising advancement toward developing a new therapy to limit breast cancer metastasis.

Results

A camelid nanobody against the N-terminus of the mouse V-ATPase c subunit was prepared using phage display. The nanobody was dimerized through disulfide bonding to create a bivalent molecule. The purified nanobody was detected using Coomassie blue staining and Western blotting. The apparent molecular weight of the dimer on SDS-PAGE was around 45 kDa, slightly faster than the predicted weight of 56.8 kDa. The nanobody was tested for its ability to inhibit V-ATPase-dependent acidification in mouse 4T1-12B cells. The nanobody treatment resulted in a similar increase in extracellular pH as treatment with concanamycin, a known V-ATPase inhibitor. 

Combining both the nanobody and concanamycin did not significantly enhance the effect. The nanobody effectively inhibited V-ATPase-dependent extracellular acidification without affecting cell viability. The anti-V-ATPase nanobody was tested for its ability to inhibit in vitro invasion of 4T1-12B cells. Treatment with the nanobody significantly inhibited invasion, like its inhibition of extracellular acidification. The nanobody effectively inhibits both extracellular acidification and in vitro invasion of 4T1-12B cells with similar affinity. 

The administration of the anti-V-ATPase nanobody was tested to determine its effect on tumor growth and metastasis in mice. Different amounts of the nanobody were administered to mice without any adverse effects. The effect of nanobody administration on in vivo metastasis was then tested using 4T1-12B cells implanted in the mammary fat pad. However, no significant difference in tumor volumes was observed between the control and nanobody-treated groups at the end of the study. Treatment with the anti-V-ATPase nanobody resulted in a significant reduction in lung metastasis but had no effect on tumor growth or leg metastases. No significant metastasis was observed in other organs. In contrast, treatment with the anti-GFP nanobody did not reduce lung metastases.

Discussion

The researchers’ previous results demonstrated that selective inhibition of cell surface V-ATPases using an antibody or bafilomycin showed potential in inhibiting invasion of breast cancer cells. However, the use of antibodies against the native c subunit proved challenging due to its conservation and limited exposure. To overcome this, a nanobody against a native epitope of the c subunit was developed through in vitro screening. This nanobody successfully inhibited cell surface V-ATPase activity in mouse 4T1-12B breast cancer cells and showed a correlation between inhibition of invasion and extracellular acidification. In mice, the nanobody treatment significantly reduced lung metastases, but had no effect on tumor growth or leg metastasis. 

The study suggests that different mechanisms may be involved in tumor cell invasion in different tissues. The potential side effects of inhibiting cell surface V-ATPases were also discussed, highlighting the limited presence of these pumps in certain cells and the potential benefits of inhibiting osteoclast function for breast cancer metastasis to bone. 

Overall, the findings support the use of inhibitory nanobodies against cell surface V-ATPases as a potential therapeutic approach to inhibit breast cancer metastasis.

“These results provide support for the use of an inhibitory antibody directed against an extracellular epitope of the V-ATPase as a potential anti-metastatic therapeutic to inhibit breast cancer metastasis.”

Click here to read the full research paper in Oncotarget.

Oncotarget is an open-access, peer-reviewed journal that has published primarily oncology-focused research papers since 2010. These papers are available to readers (at no cost and free of subscription barriers) in a continuous publishing format at Oncotarget.com

Oncotarget is indexed and archived by PubMed/Medline, PubMed Central, Scopus, EMBASE, META (Chan Zuckerberg Initiative) (2018-2022), and Dimensions (Digital Science).

Click here to subscribe to Oncotarget publication updates.

For media inquiries, please contact media@impactjournals.com.

Key Roles of MIF, DDT, and CD74 in Melanoma Prognosis and Therapy

In this new study, researchers present the first retrospective study evaluating differential gene expression of MIF, DDT, and relevant pathway markers in relation to clinical outcomes in melanoma patients.

Macrophage Migration Inhibitory Factor (MIF) and its homolog D-dopachrome Tautomerase (DDT) have been implicated as drivers of tumor progression in various cancers. Recent evidence suggests that MIF could be a therapeutic target in immune checkpoint inhibition (ICI) resistant melanomas; however, clinical evidence for MIF, and particularly for DDT, remains limited.

Researchers Caroline Naomi Valdez, Gabriela Athziri Sánchez-Zuno, Lais Osmani, Wael Ibrahim, Anjela Galan, Antonietta Bacchiocchi, Ruth Halaban, Rajan P. Kulkarni, Insoo Kang, Richard Bucala, and Thuy Tran from Yale UniversityOregon Health and Science UniversityCancer Early Detection Advanced Research Center (CEDAR); and the Department of Veterans Affairs Portland Health Care System analyzed 97 patients treated at Yale for melanoma between 2002–2020. Their research paper was published in Oncotarget’s Volume 15 on July 19, 2024, entitled, “Prognostic and therapeutic insights into MIF, DDT, and CD74 in melanoma.”

In their study, the researchers noted that melanoma is one of the most aggressive and lethal forms of cancer, with an estimated 99,700 new cases expected in 2024. The development of immune checkpoint inhibitors (ICIs) has significantly transformed cancer treatment and is now a cornerstone for managing several cancers, including advanced melanoma. Anti-CTLA-4 inhibitors, which target regulatory T cells, and anti-PD-1/L-1 inhibitors, which target activated T cells, dendritic cells, and tumor cells, have reshaped melanoma management, leading to improvements in progression-free and overall survival, with up to 22% of patients experiencing a complete response (CR). Data suggests that the ratio of CD74:MIF and CD74:DDT expression in melanoma may provide prognostic value and potentially serve as clinical biomarkers for patients with melanoma.

The study significantly expands on previous research by including a larger cohort of individuals and employing a comprehensive approach to defining high and low MIF and DDT expression. The survival analysis findings are consistent with existing literature, demonstrating that increased MIF levels are associated with worse prognosis in patients with melanoma, particularly in those with advanced disease or evidence of metastases.

The data presented in this research paper supports existing evidence on the intratumoral effects of MIF and DDT on tumor permissiveness, primarily through immune modulation, with implications for melanoma prognosis. The findings suggest that MIF and DDT may serve as therapeutic targets and biomarkers for predicting treatment response and survival, with CD74:MIF and CD74:DDT showing promise as markers of ICI response in patients undergoing treatment. Further investigation is needed to fully understand the role and functions of DDT in the melanoma microenvironment, as well as its distinct, non-overlapping functions in tumorigenesis.

“Our study is the first to report survival findings in association with intratumor DDT expression and CD74:DDT expression level ratio.”

Click here to read the full research paper in Oncotarget.

Oncotarget is an open-access, peer-reviewed journal that has published primarily oncology-focused research papers since 2010. These papers are available to readers (at no cost and free of subscription barriers) in a continuous publishing format at Oncotarget.com

Oncotarget is indexed and archived by PubMed/Medline, PubMed Central, Scopus, EMBASE, META (Chan Zuckerberg Initiative) (2018-2022), and Dimensions (Digital Science).

Click here to subscribe to Oncotarget publication updates.

For media inquiries, please contact media@impactjournals.com.