Quantum-Si Announces Two Customer Posters to be Presented at the American Association of Cancer Research Annual Meeting

Key Terms

deep mutational scanning medical

Deep mutational scanning is a laboratory method that measures how thousands of small changes in a protein’s genetic code affect that protein’s behavior, such as stability, activity, or recognition by drugs and the immune system. Investors care because it helps drug and vaccine developers predict which variants may resist treatments or alter efficacy, prioritize which candidates to advance, and reduce development risk—like stress‑testing many recipe tweaks to find the best version.

next-generation protein sequencing medical

Next-generation protein sequencing is a set of new laboratory methods that can read the exact order and modifications of amino acids in proteins much faster and at larger scale than older techniques. For investors, it matters because the ability to rapidly and cheaply decode proteins can accelerate drug discovery, enable more precise diagnostics, and create new commercial tools—similar to how faster, cheaper DNA sequencing unlocked entire biotech markets.

single-molecule protein sequencing medical

Single-molecule protein sequencing is a laboratory method that reads the exact order of building blocks in a single protein molecule, similar to reading letters in a word rather than averaging many copies. For investors it matters because it promises far more sensitive and precise detection of disease markers, faster drug discovery and highly personalized diagnostics, which could create new markets or disrupt existing lab testing and therapeutics businesses.

post-translational modifications medical

Chemical changes made to a protein after a cell builds it, acting like finishing touches that alter the protein’s shape, location, or activity. For investors, these changes matter because they control how biological targets behave, influence drug effectiveness and safety, affect biomarkers used to track diseases, and can change manufacturing or regulatory risk—similar to how tailoring can turn a basic garment into something that fits and functions differently.

ptms medical

Post-translational modifications (PTMs) are chemical changes made to a protein after it is produced by a cell, such as adding small chemical groups or cutting the protein into pieces; these tweaks can change a protein’s shape, location, stability or activity. For investors, PTMs matter because they can determine whether a drug works as intended, affect biomarker reliability, influence manufacturing consistency and quality, and therefore shape clinical outcomes, regulatory approval chances and commercial value.

proteoform medical

A proteoform is a specific version of a protein that results when the same gene produces slightly different end products through small sequence differences or chemical changes after the protein is made. For investors, proteoforms matter because these subtle differences can change how a drug works, how reliably a diagnostic test detects disease, and how regulators view safety and effectiveness—similar to how different trims of the same car model can affect performance, price, and customer choice.

biomarker studies medical

Biomarker studies investigate biological signs—such as genes, proteins, or measurable changes in blood or tissue—that indicate how a disease behaves or how a patient is likely to respond to a treatment. For investors, these studies matter because reliable biomarkers can act like early warning instruments or tailored maps, reducing drug development risk, improving trial success rates, and increasing the odds of regulatory approval and commercial uptake, all of which can materially affect a company’s value.

See more from StockTitan in Google Search and AI answers. Adds StockTitan as a preferred source · opens Google

Add on Google Not now

BRANFORD, Conn.--(BUSINESS WIRE)-- Quantum-Si Incorporated (Nasdaq: QSI) (“Quantum-Si,” “QSI” or the “Company”), a proteomics company redefining protein analysis through single-molecule protein sequencing, today announced that there will be two customer posters presented at the American Association of Cancer Research (AACR) annual meeting on April 17-22, 2026 in San Diego, California.

Poster 2421; April 20, 2026
Primary Author: Nigel O’Neil, PhD
Poster Title: Combining deep mutational scanning and next-generation protein sequencing to harness dominant protein variants to develop DNA repair inhibitors

In the first poster, the researchers describe a complementary genetic (high throughput screens) and proteomic (benchtop protein sequencing) approach to find and model the behavior of therapeutics targeting DNA repair enzymes.

Poster 7650; April 22, 2026
Primary Author: Gloria Sheynkman, PhD
Poster Title: High-resolution detection of post-translational modifications using single-molecule protein sequencing

In the second poster, the researchers demonstrated the ability to resolve and quantify multiple PTMs using Quantum-Si’s single-molecule protein sequencing technology. The authors suggested that the technology could be used to add proteoform characterization to biomarker studies, providing additional resolution not readily available in broad biomarker screening panels. The authors further concluded that they expect this technology could democratize advanced protein characterization, making the high-resolution detection of PTMs available to a broader scientific community.

“We are excited to see new customer data being presented at key industry conferences like AACR, that continue to demonstrate the power of our proprietary single-molecule protein sequencing technology,” said Jeff Hawkins, President and Chief Executive Officer of Quantum-Si. “We invested significant effort during 2025 to build a pipeline of studies that would demonstrate the power of our technology, and we are very pleased to have a steady flow of customer pre-prints, publications and posters being released this year as we work to expand awareness and build momentum towards the launch of Proteus™.”

About Quantum-Si Incorporated

Quantum-Si is transforming proteomics with a benchtop platform that brings single-molecule protein analysis to every lab, everywhere. The Company’s platform enables real-time kinetic-based detection and allows researchers to move beyond traditional, multistep workflows and directly access dynamic, functional protein insights with unparalleled resolution. By making protein analysis simpler, faster, and more informative, Quantum-Si is accelerating proteomic discoveries to improve the way we live. Learn more at quantum-si.com or follow us on LinkedIn or X.

Forward Looking Statements

This press release includes “forward-looking statements” within the meaning of the “safe harbor” provisions of the United States Private Securities Litigation Reform Act of 1995. The actual results of the Company may differ from its expectations, estimates, and projections and, consequently, you should not rely on these forward-looking statements as predictions of future events. Words such as “expect,” “estimate,” “project,” “budget,” “forecast,” “anticipate,” “intend,” “plan,” “may,” “will,” “could,” “should,” “believes,” “predicts,” “potential,” “continue,” and similar expressions (or the negative versions of such words or expressions) are intended to identify such forward-looking statements. These forward-looking statements include, without limitation, the Company’s expectations with respect to future performance and development and commercialization of products, services and applications, its anticipated cash runway, the anticipated timing of product launches and product capabilities (including Proteus), investor confidence in Quantum-Si and our strategic roadmap, and any financial guidance. These forward-looking statements involve significant risks and uncertainties that could cause the actual results to differ materially from those discussed in the forward-looking statements. Many of these factors are outside the Company’s control and are difficult to predict. Factors that may cause such differences include, but are not limited to: the inability to maintain the listing of the Company’s Class A common stock on The Nasdaq Stock Market; the ability of the Company to grow and manage growth and retain its key employees; the Company’s ongoing leadership transitions and succession planning; changes in applicable laws or regulations; the ability of the Company to raise financing in the future; the success, cost and timing of the Company’s product development and commercialization activities, including the use and benefit of artificial intelligence in these and other activities; the commercialization and adoption of the Company’s existing products and the success of any product the Company may offer in the future, including Proteus; the potential attributes and benefits of the Company’s commercialized Platinum protein sequencing instruments and kits and the Company’s other products (including Proteus) once commercialized; the Company’s ability to obtain and maintain regulatory approval for its products, and any related restrictions and limitations of any approved product; the Company’s ability to identify, in-license or acquire additional technology; the Company’s ability to maintain its existing lease, license, manufacture and supply agreements; the Company’s ability to compete with other companies currently marketing or engaged in the development or commercialization of products and services that serve customers engaged in proteomic analysis, many of which have greater financial and marketing resources than the Company; the size and growth potential of the markets for the Company’s products and services, and its ability to serve those markets once commercialized, either alone or in partnership with others; the Company’s estimates regarding future expenses, future revenue, capital requirements and needs for additional financing; the Company’s financial performance; the Company's defense and initiation of litigation matters; and other risks and uncertainties described under “Risk Factors” in the Company’s most recent Annual Report on Form 10-K and Quarterly Reports on Form 10-Q and in the Company’s other filings with the SEC. The Company cautions that the foregoing list of factors is not exclusive. The Company cautions readers not to place undue reliance upon any forward-looking statements, which speak only as of the date made. The Company does not undertake or accept any obligation or undertaking to release publicly any updates or revisions to any forward-looking statements to reflect any change in its expectations or any change in events, conditions, or circumstances on which any such statement is based.

View source version on businesswire.com: https://www.businesswire.com/news/home/20260414060888/en/

Investor and Media
Jeff Keyes
Chief Financial Officer
ir@quantum-si.com

Source: Quantum-Si Incorporated