Discussing the Mysteries of Melanoma

A Q&A with Drs. Chengyu Liang and Meenhard Herlyn on skin cancer research at The Wistar Institute, including a few questions from melanoma survivors.

Melanoma is the most aggressive form of skin cancer. Work at The Wistar Institute’s Melanoma Research Center aims to understand the biology behind the disease to help develop new therapies and improve existing treatments. In this Q&A, we spoke with Dr. Chengyu Liang, a professor in the Molecular & Cellular Oncogenesis Program at Wistar’s Ellen and Ronald Caplan Cancer Center who joined Wistar in 2020 and Dr. Meenhard Herlyn, director of The Wistar Institute Melanoma Research Center and Professor in the Molecular & Cellular Oncogenesis Program. The research they conduct aims to have impacts on melanoma patients and survivors. Thus, this National Melanoma and Skin Cancer Awareness Month, we included questions from melanoma survivors and staunch Wistar supporters Eleanor Armstrong and Pat Dean who organize an annual fundraiser walk for the Institute’s melanoma research program.

Dr. Liang, what attracted you to studying melanoma?

Dr. Chengyu Liang: My passion and curiosity! A few years ago, we identified a so-called “sunscreen” gene that helps cells to repair after they have been damaged by UV rays; and we know that UV-induced DNA damage is a major risk factor for melanoma – the most aggressive type of skin cancer. This inspired us to find out more about how this genetic sunscreen system plays in human beings and what it means to melanocytes (the origin of melanoma) and melanoma when the system is running out of order.

What are you working on now specifically regarding melanoma and what is this work’s potential impact on cancer treatments?

CL: The question that we are always intrigued by is: What makes melanoma melanoma? Compared to most other types of human cancers, one striking feature of melanoma is that its genome is flooded with mutations associated with UV-induced damage. Now, the burning questions are: What drives such genetic change? What are the molecular mechanisms underlying the UV-footprint in melanoma? Understanding these mechanisms not only enable early-risk prediction but also help oncologists and researchers to develop cancer treatments with responses that have long-term durability.

Second, melanoma originates from an easily spread and multipotent cell population, which can help explain the inborn aggressiveness and treatment resistance of the skin cancer. In addition to targeting specific pro-cancer mechanisms to kill cancer cells that are often, if not always, encountered by tumor resistance, is it possible to force cancer cells to resume the process of normal growth control or differentiation? To this end, we are trying to understand the molecular mechanisms that control melanoma differentiation. This work holds promise to identify new vulnerabilities in melanoma that can be targeted to revert the negative effects of mutations and strengthen anti-tumor immune responses to melanoma.

How important is a person’s immune system in preventing skin cancer and is there anything that can be done to strengthen a person’s immune system against melanoma?

CL: It can’t be more important! Our immune system is like the ‘shepherd’; its duty is to keep ‘sheep’ protected. Melanoma is like the ‘wolf’. A powered immune system is an experienced shepherd that could easily and quickly identify and target the wolf in the flock and clear it up. As a matter of fact, what immunotherapy does is release the built-in brake system of our immune system and revive and direct its killing energy to cancer cells.

The immune system is an ecosystem – a complex network of cells, tissues, and organs that orchestrate to maintain homeostasis to protect human bodies against internal and/or external assaults. If a well-balanced immune system is considered healthy to life, a well-balanced life would also be considered beneficial to the immune system. Many tips have been suggested such as healthy diet, exercise, mental and physical support, etc. Notably, fasting and calorie restriction (CR), have been shown experimentally and in clinical trials, to be able to slow and even stop the progression of cancer, kill cancer cells, boost the immune system, and significantly improve the effectiveness of chemotherapy and radiation therapy. With our growing understanding of this sophisticated system, we might be able to come up with more effective strategy to boost it or manipulate it to outsmart cancer.

You’ve previously done research on UV radiation causing mutations that contribute to melanoma. What are some daytime hours that have the highest risk of damaging UV radiation and sun exposure?

CL: This depends. The lighter the skin, the more sensitive to sunburn and/or skin damage by UV rays. Human skin pigmentation is an evolutionary adaptation to UV radiation. Fair skinned people may easily burn within 20 minutes of exposure to direct sunlight, thus wearing a broad-spectrum sunscreen is always encouraged. Certainly, you also want to have a strong genetic sunscreen system as noted before.

What future directions will you take your work?

CL: Our ultimate goal is to make melanoma a curable disease. The current challenge is that we still have more than 50% of melanoma patients who are not responsive to any treatment. We need to solve this puzzle. We also need to figure out what’s the right therapy to be used for the right patient at the right time. Why does therapy work in some patients, but not others? We believe that prevention is the most effective treatment of melanoma. Thus, identifying a new biomarker for early detection is equally important and urgent. All these challenges depend on a deeper understanding of the biology of melanoma as a cancer, and the biology of melanoma interaction with the human body as a system.

Dr. Herlyn, why is building the cancer research talent at Wistar important (eg. Dr. Chengyu Liang joining the Cancer Center)?

Dr. Meenhard Herlyn: Every research field needs a critical mass of researchers, both junior and senior. Any institution needs ‘new blood’, meaning investigators who may have experience, knowledge, and connections in the critical field. Dr. Liang brings important expertise not only to Wistar but the entire larger field here and beyond. Her work on DNA damage and repair fills an important gap for us.

What would you like to see for the future of melanoma research at Wistar?

MH: Melanoma has been a major focus for research at Wistar. We have developed a strong outreach program in which we collaborate not only with our colleagues at Penn but also with numerous national and international research laboratories. Melanoma research at Wistar should remain multi-disciplinary. Our strong biology is the foundation and platform for collaborations that ensure continuing progress. Melanoma investigators should incorporate cutting edge technologies and strategies. We have developed strong ties to our clinical colleagues, and we expect that in the future these ties will strengthen as our research more and more directly benefits patients. Thus, we not only translate research from bedside-to-bench but also from bench-to-bedside.

Why are supporters such as those fundraising and donating to the Institute important?

MH: There are many areas of research that are essential to run a successful program but that cannot be funded through National Institute of Health or industry grants. For example, there are meetings with other scientists to exchange ideas and develop new collaborative strategies, seed funding for new projects that are still in the exploratory phase, collaborations with clinicians for specimens and preparing reagents for diagnostic studies, developing high risk/high gain projects and ideas, and obtaining new research tools. Supporters like our donors and fundraisers are integral to our work at Wistar, without whom we could not have as great an impact as we do.