"Cold" colorectal cancer faces a bottleneck in immunotherapy

Area of Science:

• Oncology
• Immunology

Background:

• Immunotherapy, particularly immune checkpoint inhibitors (ICIs), has transformed cancer treatment.
• ICIs are effective in immunologically "hot" tumors but show limited benefit in "cold" tumors, including colorectal cancer (CRC).
• Low response rates and individual differences hinder ICI efficacy in cold tumors like CRC.

Purpose of the Study:

• To review the classification and characteristics of hot versus cold CRC.
• To summarize current research, treatment strategies, and challenges of immunotherapy for cold CRC.
• To elucidate the mechanisms and biological roles of immunotherapy in cold CRC.

Main Methods:

• Literature review of immunotherapy and immune checkpoint inhibitors in colorectal cancer.
• Analysis of hot vs. cold tumor classifications in CRC.
• Synthesis of current research on immunotherapy for cold CRC.

Main Results:

• Cold CRC presents distinct characteristics compared to hot CRC, impacting immunotherapy response.
• Current immunotherapy strategies for cold CRC are limited by low response rates.
• Understanding the mechanism and biology of immunotherapy in cold CRC is crucial.

Conclusions:

• Further research is needed to overcome challenges in treating cold CRC with immunotherapy.
• Developing novel strategies is essential for improving ICI efficacy in cold CRC.
• Clarifying the role of immunotherapy in cold CRC will guide future treatment development.